HomeMy WebLinkAboutSEPA E95-0010 - RODGER LACY - SINGLE FAMILY RESIDENCERODGER LACY
SINGLE FAMILY
CONSTRUCTION ON
WETLANDS PARCEL
51ST AVE. S.
E95-0010
April 28, 1997
City of Tukwila
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
Mr. Rodger E. Lacy Sr.
, 4133 46th Avenue S.
Seattle, WA 98108
Re: Lacy Project - Reasonable Use Exception, Land Altering Permit, L95-0001, P96-0010,
MI97-0003:
Dear Mr. Lacy:
This letter is written to verify the results of the site inspection for the mitigation plantings
installed on your property.. As you know, your design consultant and your landscape contractor
met together with Gary Schulz last week, 4/22/97. Gary Schulz has reported the mitigation plan
was professionally installed and appears to be a very good effort, consistent with the intent of the
Sensitive Areas Ordinance.
To avoid repetition, I have attached the 4/22/97 letter from Peg Ferm which is the final report
of the installed mitigation. Please note her recommended actions, items 1 thru 7, which are fairly
minor adjustments related to the installed mitigation. Per the approved Mitigation Plan, it is
anticipated that you will take care of these minor adjustments. Due to the minor nature of these
adjustments, there will not be a need for another inspection until the monitoring is completed.
As indicated by Correction Letter #1 for your Development Permit Application No. MI97-0003
(Dated February 11, 1997), a letter of credit or other security acceptable to the City must be
submitted to guarantee the proper monitoring and survival of the plantings, consistent with your
approved Monitoring and Evaluation Plan. Since the installation has been successfully completed,
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
Mr. Rodger Lacy
April 29, 1997
Page 2
this security need only cover 150 percent of the estimated costs for 1) monitoring/maintenance,
and 2) a reasonable contingency to replace plants that may die. The entire cost to install the
mitigation plan does not need to be calculated into the security. Please have the appropriate
person prepare the estimate of costs for 1) and 2) above.
Sincerely,
Steve Lancaster, Director
Department of Community Development
cc: Kelcie Peterson, Permit Coordinator
Gary Schulz, Urban Environmentalist
Vern Umetsu, Associate Planner
Joanna Spencer, Associate Engineer
peg•ferm
derign
Rodger E. Lacy, Sr.
4133 46th Ave. So.
Seattle, WA 98118
April 22, 1997
Dear Rodger,
•
P.O. SOX 1031
rA0NROE. WA 98272
380-794-841E3
This is the final report on the installation of the native plant mitigation on
your site. Inspection took place on April 22, 1997. Present were myself, Debbie
Mace' (Contractor), and Gary Schulz with the City of Tukwila.
The installation is acceptable and has been well-done. Plant materials are
generally very high quality. There were a few minor variations from the plans
(listed below), but these do not affect the quality or the acceptability of the
installation. This was discussed and verbally agreed upon by Debbie, Gary, and
myself during the site inspection.
1. One plant, a red osier dogwood, is missing. It will be installed
by the Contractor.
2. Plant substitutions were made in two locations. In each instance
the substitution was another native plant. The substitutions are
appropriate and do not affect the quality of the installation or the
intent of the plan.
3. Mulch was not used as specified on the plans (Note 8). The Contractor
stated that she will keep the area surrounding the newly installed plants
clear by clipping back other vegetation when she comes to water the plants
throughout the summer. Since the purpose of the mulch is to suppress
the growth of new vegetation that might out -compete the newly installed
plants, a maintenance plan as described will serve the same purpose.
However, this clipping back of competing vegetation must be continued
during the growing season in the absence of bark mulch. Failure to do
this during the first two years may result in failure of some of the
newly installed plants.
4. Flagging was not installed as specified on the plans (Note 14).
the Contractor states she will install this. The purpose of the flagging
is to make it easy to,find and identify the young plants when the existing
vegetation is in full leaf. The existing stakes, with names of plants
marked, will be left in place.
5. In several places, some additional pruning back of existing vegetation
will be required to give room to the newly installed plants. These places
were noted by the Contractor, and will be pruned as discussed.
6. A few newly installed trees must have loose soil pulled away from
the crowh of the root ball. The Contractor will clean this up as discussed.
7. A few of the thimbleberries have dead. canes above ground. This does
not necessarily mean the plant is dead, but those plants in particular
should be checked to make sure that new growth appears within the next
month. The Contractor has stated she will do this, and will repJir e� ���
any that do not emerge. �--'�$$ ��
APR 2 41997
COMMUNITY
DEVELOPMENT
• •
All in all, this seems to be a very well done and trouble free installation.
I expect the plants to do well if watered and kept clear of competition as described
above. The -new additions will add beauty, interest and value to your property
in the long term.
I expect this will be the end of my involvement with the project for the time
being. Please call if questions arise. I've enjoyed working with you, Rodger,
and hope you will call on me if you need design services in the future.
Peg Ferm
cc: Gary Schulz
Debbie Mace
City of Tukwila
•
•
John W Rants, Mayor
Department of Community Development Steve Lancaster, Director
October 17, 1996
Mr. Rodger E. Lacy Sr.
4133 46th Avenue South
Seattle, WA 98108
0010
Re: Lacy Project, L95c6604-Reasonable Use Exception
Proposed Mitigation Plan
Proposed Monitoring and Evaluation Plan
Dear Mr. Lacy:
The purpose of this letter is to respond to the proposed Mitigation Plan and a separate
Monitoring and Evaluation Plan (Peg Ferm Design, 8-29-96) you submitted on
September 9, 1996. Your proposed wetland mitigation appears to be located in the
nonbuilding area directly west of your proposed groundwater interceptor trench. Gary
Schulz has reported this area is mostly forested upland with wetland area on the lower
portion adjacent to where the interceptor trench is proposed.
Mitigation Plan/Monitoring and Evaluation Plan Approval
Your proposal to mitigate wetland impacts through enhancement of an area of 26,500
square feet was previously agreed upon. The proposed plantings and their location are
appropriate and consistent with previous discussions with your consultant. Based upon
our review, the following modifications and clarifications are required.
1. Assuming plant locations will not be staked in the field, the Mitigation Plan shall
indicate the appropriate spacing for trees and shrubs. This can be accomplished by
adding a "spacing" column to the plan's Plant Schedule.
2. The Mitigation Plan shall include on its face a statement that the provisions of Chapter
18.45 of the Tukwila Municipal Code control use and development of the subject
property, consistent with the requirements of TMC 18.45.130. (Please note that a plan
bearing this information must be recorded prior to issuance of a land altering permit.)
3. Revise the Enhancement Standards section of the Monitoring and Evaluation Plan to
provide for a two-year monitoring and replacement program, rather than a one-year
program. This two-year period should commence upon completion of the mitigation
planting and acceptance by the city. Reference: TMC 18.45.135.
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
Please note that, at your option, the conifer trees may be smaller in height than indicated
by the proposed Mitigation Plan. Experience shows that smaller, younger plants
(particularly native conifers) will more readily adapt to new conditions. Conifers that are
at least 4 feet in height are acceptable. Should you choose to plant smaller conifers,
please revise the Mitigation Plan Planting Schedule accordingly.
We anticipate approval of your Mitigation Plan and your Monitoring and Evaluation Plan
within one week of receiving revised plans that reflect these changes.
Performance and Maintenance Guarantee
A letter of credit or other security acceptable to the city must be submitted prior to
issuance of a land altering permit. The purpose of this security is to guarantee the proper
installation, monitoring and survival of the plantings per the Mitigation/Monitoring and
Evaluation Plans. The amount of this guarantee shall be equal to the estimated cost of
implementing the Mitigation Plan. Please have your landscape architect or other
qualified person prepare and submit an estimate of this cost. This will assist us in
establishing the amount of the letter of credit or other security. Reference: TMC
18.45.135.
Please contact me at 431-3670 if you have questions related to this letter.
Sincerely,
Steve Lancaster, Director
Department of Community Development
cc: Peg Ferm, Peg Ferm Design
Kelcie Peterson, Permit Coordinator
Vern Umetsu, Associate Planner
Gary Schulz, Urban Environmentalist
Ron Cameron, City Engineer
Joanna Spencer, Associate Engineer
•
AFFIDAVIT
OF DISTRIBUTION
If Syi--V t / JV CM lkLL-n ) hereby declare that:
fl Notice of Public Hearing
O Notice of Public Meeting
Board of
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Adjustment Agenda
Appeals Agenda
Commission Agenda
0 Short Subdivision Agenda
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'Determination of Non-
significance
Mitigated Determination of
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O Determination of Significance
and Scoping Notice
Notice of Action
00f ficial Notice
Other
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AFFIDAVIT
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fl Board of
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Hearing
Meeting
Adjustment Agenda
Appeals Agenda
[]Planning Commission Agenda
Packet
Short Subdivision Agenda
Packet
OF DISTRIBUTION
hereby declare that:
Determination of Non-
ignificance
0 Mitigated Determination of
Nonsignificance
Determination of Significance
and Scoping Notice
O Notice of Action
00f ficial Notice
Other
[]Notice of Application for []Other
Shoreline Management Permit
UShoreline Management Permit
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was ed to each of the following addresses on
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Name of Project
File Number. - , 0
Signature
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•
CI1Y OF TUKWILA
DETERMINATION OF NONSIGNIFICANCE (DNS)
DESCRIPTION OF PROPOSAL:
Construct a 3.500 s.f. house with a 5.000 s.f.
development area on a 1.5 acre parcel. The parcel
has extensive wetlands and a reasonable use
exception for wetland development (about 17.700
s.f.) was granted by the Tukwila Planning Comm.
per TMC 18.45_115, on April 27. 1995 (L95-0001).
PROPONENT: RODGER LACY
LOCATION OF PROPOSAL. INCLUDING STREET ADDRESS, IF ANY:
ADDRESS:
PARCEL NO:
SEC/TWN/RNG:
LEAD AGENCY:
810860-0420'
23/23/04
CITY OF TUKWILA FILE NO: E95-0010
The City has determined that the proposal doe not have a probable
significant adverse impact on the environment. An environmental
impact statement (EIS) is not required under RCW 43.21c.030(2)(c).
Thts decisionwas made after review of a completed environmental
checklfst and other information on file with the lead agency. This
information ts available to the public on request.
**4,-*********4,A*A.A..A***A*AAVVW*4,644,MA**********AW***4.******4*********
This determination is final and signed this S111- day of J.0.4e.
199
Steve Lancaster, Responsible Official
City of Tukwila, '(206) 431-3670
6300 Southcenter Boulevard
Tukwila, WA 98188
Copies of the procedures for SEPA appeals are available with the
Department of Community Development.
Determination of Non -significance for
E95-0010 (Lacy Residence)
Modification of Environmental Checklist
May 14, 1996
B.3.a. Surface Water (Wetlands)
The majority of the 1.5 acre site is a City of Tukwila Class II
wetland and wetland buffer (see CSS wetland delineation report).
The proposed action would displace about 17,700 s.f. of wetland
and wetland buffer area.
A "reasonable use exception" was issued by the Tukwila Planning
Commission to allow the proposed development, pursuant to•TMC
18.45.115 on April 27, 1995 (file L95-0001) with conditions (see
attached "Notice of Decision," May 4, 1995).
A Planning Commission condition is that all wetland enhancement
shall be approved and installed: "prior to the issuance of the
building permit." This is determined to allow issuance of other
development permits as long as there are no impacts to the
wetland. This would primarily allow construction of the off-site
driveway and sewer line, as well as very limited on-site driveway
construction.
No construction activities would be allowed which:
1. affected the wetland area,
2. involved issuance of the building permit, or
3. is reasonably tied directly with building construction
prior to compliance with all Planning Commission conditions.
The Planning Commission conditions were incorporated into this
SEPA review for purposes of describing the proposed action,
impact evaluation and mitigation.
TUKWILA DEPARTMENT OF COMMUNITY DEVELOPMENT
INTER -OFFICE MEMO
TO: Project File No. E95-0010
FROM: Steve Lancaster
SUBJECT: Proposed single family home development under Reasonable Use Exception
SEPA Threshold Determination
DATE: May 6, 1996
After reviewing the environmental checklist and staff analysis, together with other information
related to this proposal; and based upon the conditions of approval imposed by the Planning
Commission under a reasonable use permit; and based on impact mitigation provided by
compliance with the requirements of the Sensitive Area Overly (SAO) provisions of the Tukwila
Zoning Code; I have determined that this proposal will not have a significant adverse
environmental impact.
1
City of/"Tukwila
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
Mr. Rodger E. Lacy Sr.
4133 46th Avenue South
Seattle, WA 98108
Re: Lacy Project, L95-0001 Reasonable Use Exception
Request to modify mitigation ratio requirement
Dear Mr. Lacy:
April 25, 1996
After reviewing the Wetland Assessment and Impact Analysis prepared by Cooke Scientific
Services (CSS), which you submitted on April 23, 1996, we find that our area of disagreement is
minor. For the purpose of resolving our disagreement, we are willing to accept the wetland
impact figure provided by the CSS assessment (17,700 square feet), subject to the following:
The mitigation plan required by Chapter 18.45 Tukwila Municipal Code (Sensitive Areas
Overlay) will be prepared after your specialist has met on-site with the City's designated
representative to discuss the objectives, locations and specific nature of appropriate
enhancement. The City's representative will explain the specific criteria that will be used to
review the plan, and will answer questions about specific enhancement needs and techniques.
This meeting will be memorialized through a letter to you that will serve as guidance for the
preparation, submittal and review of your mitigation plan.
The construction of reasonable and necessary access to your homesite within the public right-of-
way for south 158th Street will be considered exempt from the tree permit and replacement
requirements of Chapter 18.54 TMC, as long as public access within the right-of-way is not
restricted (see TMC 18.54.050, Exempt Activities). Appropriate revegetation of disturbed areas
will be required.
The CSS impact figure indicates accomplishing the required 1.5:1.0 enhancement on-site is
feasible. Therefor, and on the basis of the points listed above, it is my understanding that you
wish to withdraw your request that the Tukwila Planning Commission reduce the required
wetland enhancement ratio from 1.5:1:0 to 1:1. If this is correct, please indicate by signing
below.
5- lailo
Steve Lancaster, Director
Department of Community Development
cc: File # L95-0001
d_•rL
147( 61'=
(Signature indicates agreement)
6300 Southcenter Boulevard, Suite #100 ° Tukwila, Washington 98188 ° (206) 431-3670 0 Fax (206) 4313665
IIIDate: 12 -Apr -96 17:20 •
From: RON-C (RON CAMERON)
To: STEVE
Copies -to: GARY-SCHULZ,JOANNA,VERNON
Subject: lacey dw
Message -id: D8906E3101DEDEDE
so now
js and i remember alil more
he did submit for dw
gary/joanna/phil and i went up and reviewed
i/joanna met rl up there and questioned his showing 500 yds on app
he added trees to plan for dcd review/blessing
and that's where we remember it being... gary/vern? to give us what to do about
trees,
we need to check drawing and quantity calcs
have not heard/nor discussed more with gary or vern... you want all us to get
together for driveway review?
Cooke Scientific Services
phone / :fax! (206) 4,40-3130;:
Mr. Rodger Lacy
4133 46th Ave S.
Tukwila, WA 98118
4231 NE 110 St.
Seattle, WA 98125
..................
IVSD
..................
APR 2 3 1996
COMMUNITY
DEVELOPMENT
EMAIL ;SCOOKEOU Washington Edtt
April 10, 1996
WETLAND ASSESSMENT AND IMPACT ANALYSIS
Dear Mr. Lacy:
At your request, Cooke Scientific Services performed a wetland
assessment of your property on April 3, 1996. The site is located northwest of
the cul de -sac at the northern extent of 51st Avenue SE in the City of Tukwila.
The evaluation of the site included the following:
• Review of the wetland delineation done by Watershed Dynamics.
• Examine the area of the site recently cleared of blackberries for
wetland characteristics.
• Assess the potential for secondary impacts to areas uphill from the
site.
Wetland Determination Procedures outlined in both the US Army
Corps of Engineers (Corps) Wetlands Delineation Manual (1987) were used
during the site survey. The wetland assessment was done by examining the
soils, vegetation and hydrology at five sample plots (indicated as "DP" on the
sketch of the site included as an Attachment).
Dominant (greater than 20 percent cover) and subdominant plant
species in each vegetation stratum (tree canopy, shrub zone, and ground
cover) were recorded for each plot. Each plant's wetland indicator status was
assigned using the US Fish and Wildlife Service National List of Species that
Occur in Wetlands: Northwest—Region 9 (Reed 1991, 1993). The indicator
code for plant species is noted below:
Cooke'Scientific>Services -- Ay�a123.1996
1
Code Designation
Wetlands probability
(percent chance that plant
will be found in a wetland)
OBL
FACW
FAC
FACU
UPL
NI
Obligate wetland species
Facultative wet
Facultative
Facultative upland
Obligate upland
No indicator status
> 99
67 to 99
34 to 66
1 to 33
<1
Current Site Conditions: (refer to attached map for sample locations)
Sample Plot DP 1: Is located between the old road bed and Flag A3, which is
part of Watershed Dynamics' delineation. Vegetation consists of grasses and
forbs characteristic of disturbed areas. The dominant species include bluegrass
(Poa sp.), tall fescue (Festuca arundinacea, FAC- ), dandelion (Taraxacum
officinalis, NI), creeping buttercup (Ranunculus repens, FAC), and English
plantain (Plantago lanceolata, FAC). The soil at this plot is a very dark brown
(10YR 2/2) and dark brown (10YR 3/3) gravelly loam which appears to be fill
material. No evidence of wetland hydrology was observed. The soil fails to
meet the hydric criteria, there is no evidence of hydrology and the vegetation
is more indicative of disturbed areas than wetlands. This area was therefore
determined to be upland.
Sample Plot DP 2: Is approximately 64 feet west of the culvert under the old
road bed. It is within an area that meets the federal criteria to be considered a
wetland. It is an emergent wetland community consisting primarily of
slender rush (Juncus tenuis, FACW-) with small -fruited bulrush (Scirpus
microcarpus, OBL) as the subdominant species. Also present at this sample
plot is American brooklime (Veronica americana, OBL), Watson willowherb
(Epilobium watsonii, FACW-) and watercress (Rorippa nasturtium-
aquaticum, OBL). The soil is coarse sand with mottles and organic
streaking,and was saturated at the time of the site visit. The source of water
to this wetland appears to be hillside seeps.
Sample Plot DP 3: Is approximately 125 feet west of the culvert under the old
road and approximately 15 feet south of the north property line. It is
emergent wetland with vegetation similar to that at Sample Plot #2. The
dominant species is slender rush. American brooklime and Watson
willowherb were also observed. The soil at Sample Plot #3 is very dark gray
(10YR3 /1) sandy loam with strong mottles and gleying. Saturation was
evident at the surface.
Sample Plot DP 4: Is near Watershed Dynamics' wetland boundary flag A5. It
is a disturbed upland area characterized by upland grasses and forbs on what
appears to be fill material. The dominant plants are bluegrass and tall fescue,
Cooke Scientific Services April 23,1996
2
•
with a small component of creeping buttercup and cat's ear (Hypochaeris
radicata, NI). The soil is dark brown (10YR 3/3) sandy loam. No evidence of
wetland hydrology was observed.
Sample Plot DP 5: Is approximately 15 feet north of Sample Plot #4, with the
same soil characteristics. It is in an emergent plant community dominated by
reed canary grass (Phalaris arundinacea, FACW) and curly dock (R u m ex
crispus, FACW). Traces of large -leaf avens (Geum macrophyllum, FACW-)
and Cooley's hedge nettle (Stachys cooleyae, FACW) were also observed.
CSS examined the wetland delineation flagging placed by Watershed
Dynamics and reviewed their report dated November 4, 1995. The Watershed
Dynamics report described a Type 2 wetland, and four drainage corridors.
Two of the drainage corridors meet the Tukwila definition of a watercourse
although the type of watercourse was not evaluated. This designation still
applies under the current Tukwila Municipal Code (18.45, December 1995).
On the basis of the field assessment and report, the wetland delineation
boundaries are correct and accurate.
Project Impact Evaluation:
The geotechnical evaluation performed by the Galli Group (1995)
describes the site as a historic landslide area with deposits composed of
braided silty sands, silts and sands. There are extensive areas of fill associated
with the road, and construction of the Tukwila Interchange. Galli
recommends the use of interceptor trenches in order to de -water the building
pad. They also recommend that no surface water wetland mitigation nor
above -ground stormwater conveyance occur, as it would increase the chances
of erosion downslope. This includes re-routing an existing surface drainage.
Given the expertise of the Galli Group, and the geologic conditions of the site,
CSS recommends that wetland mitigation does not include either of these
components.
The total area calculated by the Galli Group to be within the impact
area of clearing limits for the proposed development of the site is 17,700 ft2
(0.406 acres). The Tukwila code requires a 50 foot buffer be placed around a
type 2 wetland.
As the qualified hydrologic and geotechnical experts, The Galli Group
has stated that given the nature of the soils (braided deposits of silty sands,
silts and sands), the five foot deep interceptor trenches designed to de -water
the building pad will not likely impact the hydrology of the entire property,
east and north of the trenches. These estimates are attached as an addendum
to this letter. Based on our site visit, and our qualifications as a soil scientist,
CSS agrees that the impact of the ditches will most likely be localized and that
seeps will likely reappear downslope. The 17,700 ft2 impact estimate includes
Cooke Scientific Services : April 23,1996
3
•
the wetland area that may be subject to secondary de -watering effects of the
ditches. As qualified wetland ecologists, botanists and soil scientist, CSS staff
feels this estimate is wholly appropriate, as secondary effects may include a
slight drying of some of the areas adjacent to the trenches which may affect
the wetland plant community. It is not appropriate however to include the
upland areas to the north and east of the trenches (as indicated in the 30,000
ft2 estimate determined by the City of Tukwila staff- qualified wetland
ecologist but not hydrologist) in the impact area, as the impacts from the
trenches are hydrologic in nature and the upland areas by definition do not
have hydrology. Upland areas do not have to be mitigated by the Tukwila
Municipal Code (1995).
References:
Galli Group. 1995. Geotechnical Investigation, Roger E. Lacey Sr. Residence,
51st Avenue South, Tukwila, Washington. March 15, 1995
City of Tukwila. 1995. Tukwila Municipal Code Chapter 18.45- Sensitive
Areas Overlay.
Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation
Manual. Technical Report Y-87-1, US Army Corps of Engineers
Waterways Experimental Station, Vicksburg, Mississippi.
Reed, P. B. 1988. National list of species that occur in wetlands: Northwest—
Region 9. U.S. Fish and Wildlife Service. Welut 86/WIZ. 47.
Reed, P. B. 1993. Supplement to the National List of Species that occur in
wetlands: Northwest - Region 9. U.S. Fish and Wildlife Service.
Watershed Dynamics, Inc. 1994. Lacey Project Site- Wetland Evaluation and
Delineation. November 4, 1994.
We hope this information is helpful to you. Please do not hesitate to call at
(206) 440-3130 if we can provide further assistance.
617
Sincerely,
Cooke Scientific Services
Esther S. Howard " arah Spear Cooke Ph.D.
Wetland Biologist Wetland Ecologist, Soil Scientist
Enclosure: Galli Group Impact note; Site Map (including CSS sampling
stations and Galli Group impact areas)
Cooke Scientific Services April 23,1996
4
•
Designated
Area
Wetland
Footage
sag. ft)
A
1,600
0
840
C
555
0
Z310
E
1,763
F
8,190
G
1,125
H
1,188
I
170
TOTAL
17,741
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The Galli Group, Inc.
13500 Lake City Way N.E., Suite 202
Seattle, WA 98125 (206) 363-6449
Rodger E. Lacy Sr. Residence
Tukwila, Washington
Wetland Impacts
Figure 1
NOTE TO RODGER E. LACY FILE NO. 1041-01
Re: Estimate of Wetland Area subject to Delineation
Rodger called me on 3-18-96 indicating that Tukwila had arrived at a figure of 30,000 square feet of
wetlands subject to mitigation for his property. He was wondering why the difference between our
previous number of 12,900 and this number.
Gary appears to have calculated the impacted area as all land east of the westernmost interceptor trenches
(I estimate about 29,500 square feet).
I estimated 12,900 to 16,200 square feet depending on whether road right-of-way is included, drainage
ditches are included, and area above interceptor trenches are included. hi the past I gave Rodger a 16,200
figure (8-1-95) and followed that with a more detailed calculation if certain exclusions were to apply (see
letter dated 9-20-95, Wetland Area Impacts). This number approached 12,000 square feet if exclusions
for "previously altered land" were allowed. These were numbers developed from test pit observations
indicating fill and previous photos and history of the site. We do not claim to be wetland biologists or
capable of delineating wetlands. Our intent was to provide square footage estimates if certain conditions
were excluded from impacted areas.
The primary difference appears to be in whether area east of the proposed house site previously classified
as "upland" by Mr. Lacy's Wetland Biologist (Watershed Dynamics Report, 11-4-94) is included in the
impacted calculation. The City of Tukwila does not appear to exclude this upland area in their
calculation.
The Watershed Dynamics' wetland biologist boundary was drawn based upon pacing and rough
measurements. Subsequently the property was surveyed and the biologist's flags referenced to the
boundary. In our calculations we have attempted to identify where this boundary is in the field by the
location of drainage ditches, flags, and test pits evidencing fill. We then approximated the boundary of
the upland area and excluded all upland areas east and north of the °boundary in our calculation of
impacted wetlands. However, our efforts were in attempt to more accurately identify the boundary
previously shown in the Watershed Dynamics report, not to delineate wetlands.
A couple questions remain:
1) Are areas classified as "upland" to be included as wetlands that need to be mitigated? If not,
as we assumed, how big is this upland area? Watershed Dynamics report sketches it as being all
areas east of the roadway and easternmost drainage ditch, approximately 7,000 square feet. Based
upon the actual survey and our interpretation of the site features (including test pits) we estimated it
could be as much as 14,000 square feet.
Are previously disturbed areas consisting of fill soils included as areas subject to mitigation?
If not, as we assumed, then the boundary shown on our communication to Mr. Lacy is
representative of the boundary between disturbed areas evidencing fill soils, and other areas on the
property identified as "wetland" by Watershed Dynamics in their report.
April 1, 1996
City of Tukwila
•
•
Department of Community Development
Ms. Peg Ferm
Peg Ferm Design
P.O. Box 1031
Monroe, WA 98272
Re: Wetland Mitigation/Enhancement for Lacy Project, E95-0010.
Dear Peg:
John W. Rants, Mayor
Steve Lancaster, Director
I am writing to respond to the mitigation question in your 3/14/96 letter addressed to me. The
Planning Commission established a set of conditions for the sensitive area use on the Lacy
property - Reasonable Use Exception hearing. Condition #4 requires on-site wetland
enhancement to mitigate the impacted wetland area at a ratio of 1.5:1.0. The Department of
Community Development (DCD) has evaluated the current site grading and drainage plans. It
is our opinion that the condition that specifies a mitigation ratio of 1.5:1.0 wetland area
enhancement can not be achieved on the site.
A revised mitigation/enhancement concept and reduced mitigation ratio is not an administrative
decision for this project. A new Planning Commission hearing is needed to resolve the sensitive
area mitigation issues. DCD's position regarding the required mitigation is to support on-site
enhancements, where feasible.
The new Reasonable Use hearing is tentatively scheduled for April 25, 1996. Prior to this
hearing, staff cannot approve a mitigation/enhancement plan that does not achieve 1.5:1.0 wetland
enhancement. I hope this letter answers your question for now. If you need more information,
you may contact Vernon Umetsu at 431-3670.
Sincerely,
C.
C. Gary S 'ulz
Urban Environmentalist
cc: Rodger Lacy, Sr.
Steve Lancaster, DCD Director
Vernon Umetsu, DCD Associate Planner
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
March 15, 1996
City of Tukwila
0
•
Department of Community Development
Mr. Rodger E. Lacy Sr.
4133 46th Avenue S.
Seattle, WA 98108
Re: Lacy Project, E95-0010 Review for Environmental and Land Altering.
Dear Mr. Lacy:
Q
John W. Rants, Mayor
Steve Lancaster, Director
The purpose of this letter is to respond to plans you submitted on February 12, 1996 in connection with your
application for a Land Altering Permit. I will also respond to your March 8, 1996 letter regarding SEPA and Tree
Permit exemptions. This letter addresses only the aspects of your applications relating to approvals by the
Department of Community Development (DCD).
The Department of Community Development has reviewed the plans submitted for land altering, surface and
subsurface water drainage control, and the tree and wetland mitigation permitting. The Public Works Department
has informed us that your land altering permit and related applications include 1) House Site, 2) Right -of -Way/
Access Driveway, and 3) Sewer Extension.
1) House Site
Information you have provided, including information prepared by your consultant, Watershed Dynamics, indicates
the majority of the eastern portion of your house site is wetland. Tukwila's Urban Environmentalist, Gary Schulz,
has confirmed the wetland information and advised me that the only upland area being developed on your site is the
old road fill.
Using the plans submitted for the Land Altering Permit, the calculated wetland impact is estimated to be 30,000
square feet. Therefore, the required mitigation enhancement ratio of 1.5:1.0 would provide an area of 45,000 square
feet. The area of impact is the entire building site extending east of the interceptor trench grading, except the fill
for the old road on the property.
Our review of plans for drainage modifications and grading for the House Site indicates very little opportunity for
wetland enhancement in the eastern portion of the property. The modified open water features (re-routed drainage
channel & detention pond) are not appropriate areas for wetland enhancement. The re-routed drainage channel is
designed to be rock -lined or concrete. The site's detention pond requires a synthetic liner, and maintenance will be
needed to control sedimentation. Your conceptual mitigation does not include enhancing this area; however, some
upland plantings could be used around these features for stabilizing and enhancing the alterations. Any enhancement
on the developed portion of the site will be your option to do so.
Your proposed wetland mitigation appears to be located in the nonbuilding area directly west of the interceptor
trench. The nonbuilding area proposed for wetland mitigation was not included in the wetland study but is measured
to be about 31,050 square feet. Gary Schulz has reported this area is mostly forested upland with some wetland
seepage on the lower portion adjacent to where the interceptor trench will be installed.
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
•
Mr. Rodger Lacy
March 15, 1996
Page 2
The estimated wetland impact is 30,000 square feet which is most of the eastern portion of the property. Because
there is only approximately 31,000 square feet of property available for mitigation, it will not be possible for you
to meet the Planning Commission's requirement for 1.5:1.0 wetland enhancement on the site. Therefore, options
include off-site mitigation or a modification of the Planning Commission's mitigation ratio condition. The
Department of Community Development will support a modification to the Planning Commission's condition, to
allow a 1.0:1.0 mitigation ratio. This will enable you to complete the required mitigation on-site. We are supporting
this reduction in the standard mitigation requirement because your application is for one single family house on an
existing legal building lot. We believe this level of flexibility is in keeping with the intent of the reasonable use
exception provisions of the City's sensitive area regulations.
Reduction of the mitigation ratio will require the approval of the Planning Commission. We have scheduled this
matter to go before the Commission on March 28, 1996 in order to avoid any unnecessary delay to your project.
If the Planning Commission agrees to the reduced mitigation ratio, you will be required to submit a detailed
mitigation/enhancementplanting plan for the western area of your site. This plan must be prepared by a professional
designer or licensed landscape architect. We anticipate this plan will provide for mitigation consisting mostly of
wetland buffer and sensitive slope enhancement by planting native trees and shrubs throughout the western portion
of your property.
DCD will require this plan to be submitted and approved prior to issuance of a land altering permit for your house
site. I would suggest that your designer or landscape architect discuss plan contents and expectations with Gary
Schulz at your earliest opportunity.
21 Right-of-Way/Access Driveway
You asked in your March 8 letter whether construction of your driveway within public right-of-way is exempt from
the requirements for a Tree Permit, under the provisions of TMC 18.54.050. The referenced exemption is for streets
and utilities. The term "street" is defined in TMC 18.06.790 as a "public thoroughfare." Your proposal is for a
private driveway, and is therefore not exempt.
The Right-of-Way/Access Driveway portion of the project will remove trees located on sensitive slopes (20% or
greater) and within wetland buffer area. In accordance with the Tree Regulations Ordinance (TMC 18.54), the Tree
Permit is needed because your driveway will be built within these sensitive areas.
In order to finalize the Tree Permit, we are requesting the following. Survey of the significant trees to be removed
is not necessary but those trees need to be marked on the site with plastic flagging. In addition, the boundary of the
clearing and grading needs to be located and marked in the right-of-way. Tree removal and potential wetland impact
can then be verified in the field.
A final planting plan must be prepared by a professional landscape designer or landscape architect. Appropriate tree
replacement, and any tree retention or tree protection measures should be included in the final planting plan drawings
(TMC 18.54.130). DCD will require that this plan be submitted and approved prior to issuance of a land altering
permit for your access driveway. Once again, I would suggest that your landscape designer or landscape architect
discuss plan contents and expectations with Gary Schulz when developing the plan.
•
Mr. Rodger Lacy
March 15, 1996
Page 3
3.1 Sewer Extension
You asked in your March 8 letter whether construction of your proposed 8 inch sewer line is exempt from SEPA
review under the provisions of WAC 197.11.800(24). I have determined that the proposed sewer line is not exempt
from SEPA, since it is a segment of your overall proposal, and your overall proposal includes a series of actions
functionally related to one another, some of which are not categorically exempt (see WAC 197-11-305(1)(b)).
However, I have also determined that the information you have submitted on the sewer extension is sufficient for
us to include in the SEPA review for your overall project. No additional information relating to the sewer line will
be needed for SEPA purposes.
SEPA Status
We now have all the information we need from you relative to our SEPA environmental review. We expect to issue
a Mitigated Determination of Non -Significance (MDNS) for your proposal within two weeks. You can anticipate
that the MDNS will contain several project conditions, including the requirements for a mitigation/enhancement
planting plan and a final Tree Permit planting plan as described previously in this letter.
Summary
* We have determined that you cannot meet the Planning Commission's requirement for 1.5:1.0 wetland
mitigation on the site. We will support a proposal before the Planning Commission to revise this
requirement to be 1.0:1.0, which is achievable on your site. If this revision is approved, you will be
required to submit a mitigation/enhancement plan demonstrating compliance.
* You will be required to obtain a Tree Permit for removal of any trees within the City's Right -of -Way. A
planting plan for replacement of any trees removed will be required prior to issuance of a Land Altering
Permit for your driveway.
SEPA review requirements for your proposed 8 -inch sewer line extension will be satisfied by issuance of
the MDNS for the overall project.
We anticipate issuing the MDNS for your project within the next two weeks assuming you are agreeable
to the approach outline in this letter for resolving the outstanding environmental issues.
This letter addresses only the aspects of your Land Altering Permit applications pertaining to sensitive areas
regulations, tree regulations, and SEPA compliance. It is my understanding that the Department of Public
Works is continuing to review and process your Land Altering Permit application and your sewer
construction plans.
Please contact me, or Vernon Umetsu at 431-3670, if you would like to discuss this letter.
Steve Lancaster
DCD Director
cc: Gary Schulz, Urban Environmentalist
Vernon Umetsu, Associate Planner
Ron Cameron, City Engineer
Joanna Spencer, PW Development Engineer
Jack Pace, Senior Planner
Kelcie Peterson, Permit Coordinator
Rodger E. Lacy Sr.
March 8, 1996
City of Tukwila
Mr. Steve Lancaster
City of Tukwila
Director of DCD
6300 Southcenter Blvd.
Tukwila, WA. 98188
Dear Mr. Lancaster:
I am writing you with regards to a letter sent to me, and copy furnished to you by Ron Cameron dated
March 4, 1996 concerning the sewer extension project for my property (see enclosure 1). I would like to
bring to your attention a portion of item number (10 ) which states "since the excavation and backfill will
exceed 500 cu yds. Therefore, a SEPA application will be required." IAW WAC 197-11-800 paragraph
24 titled "Utilities" utilities like sewer (b) are exempt from the SEPA requirement except "on lands
covered by water" (see enclosure 2). If you were to look at the routing of the 8" sewer main extension, it
doesn't go through wetlands or land covered with water (see enclosure 3).
I also have another question concerning the tree permit regulation under the Tukwila Municipal Code
"('SMC). Under the provisions of TMC 48.54.050 titled "Permit - exempt activities", subparagraph (F)
states "Construction and maintenance of streets and utilities within City -approved rights-of-way and
easements" are exempt. Wouldn't I be eligible for this exemption with the utility work that I am doing
within the S. 158th Street right-of-way? If not, why not? I await your response. Thank you for your
time.
Sincerely,
dCo?
Rodger E. Lacy Sr.
Enclosures: 1 Letter from Ron Cameron dated March 4, 1996.
2 Copy of WAC 197-11-800, paragraph 24,
3 Copy of the sewer extension plans.
REI FD
MAR / 1996
c:O M
'TY
DE ELOP NT
RECEIVED
1AR 12 1996
vu v MUNITY
DEVELOPMENT
SEPA Rules Part Nine -197-11-800
ambulances, and tow trucks: Provided, That regulation
of common carriers by the utilities and transportation
commission shall not be considered exempt under this
subsection.
(g) All licenses for food or drink services, sales, and
distribution, including but not limited to restaurants, li-
quor, and meat.
(h) All animal control licenses, including but not lim-
ited to pets, kennels, and pet shops. Establishment or
construction of such a facility shall not be considered
exempt by this subsection.
(i) The renewal or reissuance of a license regulating
any present activity or structure so long as no material
changes are involved.
(15) Activities of agencies. The following administra-
tive, fiscal and personnel activities of agencies shall be
exempt:
(a) The procurement and distribution of general sup-
plies, equipment and services authorized or necessitated
by previously approved functions or programs.
(b) The assessment and collection of taxes.
(c) The adoption of all 'budgets and agency requests
for appropriation: Provided, That if such adoption in=
eludes a final agency decision to undertake a major ac-
tion, that portion of the budget is not exempted by this
subsection.
(d) The borrowing of funds, issuance of bonds, or ap-
plying for a grant and related financing agreements and
approvals.
(e) The review and payment of vouchers and claims.
(f) The establishment and collection of liens and serv-
ice billings.
(g) All personnel actions, including hiring, termina-
tions, appointments, promotions, allocations of positions,
and expansions or reductions in force.
(h) All agency organization, reorganization, internal
operational planning or coordination of plans or
. functions.
(i) Adoptions or approvals of utility, transportation
and solid waste disposal rates.
(j) The activities of school districts pursuant to deseg-
regation plans or programs; however, construction of
real property transactions or the adoption of any policy,
plan or program for such construction of real property
transaction shall not be considered exempt under this
subsection (see also 197-11-800(7)).
(16) Financial assistance grants. The approval of
grants or loans by one agency to another shall be ex-
empt, although an agency may at its option require
compliance with SEPA prior to making a grant or loan
for design or construction of a project. This exemption
ineludes agencies taking nonproject actions that are nec-
essary to apply for federal or other financial assistance.
(17) Local improvement districts. The formation of
local improvement districts, unless such formation con-
stitutes a final agency decision to undertake construction
of a structure or facility not exempted under 197-11-
800 and 197-11-880.
(18) Information collection and research. Basic data
collection, research, resource evaluation, requests for
proposals (RFPs), and the conceptual planning of pro-
posals shall be exempt. These may be strictly for infor-
mation -gathering, or as part of a study leading to a
proposal that has not yet been approved, adopted or
funded; this exemption does not include any agency ac-
tion that commits the agency to proceed with such a
proposal. (Also see 197-11-070.)
(19) Acceptance of filings. The acceptance by an
agency of any document or thing required or authorized
by law to be filed with the agency and for which the
agency has no discretionary power to refuse acceptance
shall be exempt. No license shall be considered exempt
by virtue of this subsection.
(20) Procedural actions. The proposal or adoption of
legislation, rules, regulations, resolutions or ordinances,
or of any plan or program relating solely to governmen-
tal procedures, and containing no substantive standards
respecting use or modification of the environment shall
be exempt. Agency SEPA procedures shall be exempt.
(21) Building codes. The adoption by ordinance of all
codes as required by the state building code act (chapter
19.27 RCW)..
(22) Adoption of noise ordinances. The adoption by
counties/cities of resolutions, ordinances, rules or regu-
lations concerned with the control of noise which do not
differ from regulations adopted by the department of
ecology under chapter 70.107 .RCW. When a
county/city proposes a noise resolution, ordinance, rule
or regulation, a portion of which differs from the appli-
cable state regulations (and thus requires approval of the
department of ecology under RCW 70.107.060(4)),
SEPA compliance may be limited to those items which
differ from state regulations.
(23) Review and comment actions. Any activity where
one agency reviews or comments upon the actions of an-
other agency or another department within an agency
shall lie exempt.
(24) Utilities. The utility -related actions listed below
'shall- be exempt, except for installation, construction, or
alteration on lands covered by water. The exemption in-
cludes installation and construction, relocation when re-
quired by other governmental bodies, repair,
replacement, maintenance, operation or alteration that
does not change the action from an exempt class.
(a) All communications lines, including cable TV, but
not including communication towers or relay stations.
(b) All storm water, water and sewer facilities, lines,
equipment, hookups or appurtenances including, utiliz-
ing or related to lines eight inches or less in diameter.
(c) All electric facilities, lines, equipment or appurte-
nances, not including substations, with an associated
voltage of 55,000 volts or less; and the overbuilding of
existing distribution lines (55,000 volts or less) with
transmission lines (more than 55,000 volts); and the un-
dergrounding of all electric facilities, lines, equipment or
appurtenances.
(d) All natural gas distribution (as opposed to trans-
mission) lines and necessary appurtenant facilities and
hookups.
(e) All developments within the confines of any exist-
ing electric substation, reservoir, pump station or well:
[Ch. 197-11 WAC -p 29]
March 4, 1996
Mr. Rodger Lacy
4133 46th Ave. S.
Seattle, WA 98118
Dear Mr. Lacy:
City of Tukwila
John W. Rants, Mayor
Department of Public Works Ross A. Earnst, P. E., Director
As per our phone conversation held on Friday, March 1, 1996, I would like to reiterate in writing the
following issues concerning your project:
1. Place hill holds on steep grades;
2. Place locking lids on the man -holes for each new connection;
3. Phase construction through the drain fields;
4. Provide a legal description of the easement;
5. Develop a maintenance agreement as we he had discussed;
6. Permit required for each connection with a METRO connection fee (enclosed is a METRO
form);
7. A METRO permit will be required from METRO for connection at 53rd Ave. S.;
8. Develop a provision for future connections to be permitted by the City with a late comers
agreement reimbursing the owner(s);
9. Show where the pipe is in the WSDOT right-of-way and obtain a WSDOT permit for the
said pipe;
10. Land altering permit is needed since the excavation and backfill will exceed 500 cu yds.
Therefore, a SEPA application will be required. Please contact Kelcie Peterson in the
Permit Center at 431-3670 for information regarding the application and its submittal.
If there is anything that I can further assist you with, please call me at 433-0179. Thank you.
Sincerely,
Ron Cameron, PE
City Engineer •
RMC/mev
Enc. a/s
cf: Steve Lancaster, Planning Director
Jack Pace, Senior Planner
q:\mev\lacey4.doc •
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • Phone: (206) 433-0179 • Fax (206) 431-3665
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•
City of Tukwila
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
December 11, 1995
Mr. Rodger E. Lacy Sr.
4133 46th Avenue S.
Seattle, WA 98188
Re: Lacy Project, E95-0010.
Dear Mr. Lacy:
This letter is written in response to the questions and concerns included in your September 19, 1995 letter.
Even though you have told staff during several recent conversations that written response is not urgent, I feel
it is important to clarify several points at this time. I have identified the issues and listed them below in about
the same order contained in your letter. In addition, this letter provides the procedural steps you need to take
to continue processing the proposed Reasonable Use Exception for a single residence.
RESPONSE TO SEPTEMBER 19, 1995 LETTER:
1) Gary Schulz, the City's environmental coordinator has written you and reported to me that your previous
wetland consultant performed a field investigation and provided a report (Watershed Dynamics 11/4/94) to
describe existing conditions on your property. They collected representative data throughout the central and
eastern portions of your property. Based on Watershed Dynamic's 11/4/94 Wetland Letter Report, your
property is mostly wetland except for the old road fill that enters the eastern part of the site. To date, this
is the only wetland evaluation submitted to the City.
2) There is no question that your site has had clearing and land altering activities in the past. Excavated
channels are present from probable attempts to drain the area. However, these drainage and wetland areas
are not exempt from Tukwila's Municipal Code (TMC 18.06.176) or RCW 36.70A.030. Both the RCW and
TMC definitions only exempt wetlands that were "constructed" from nonwetland sites, and not created for the
purpose of compensatory mitigation. Also, the watercourse definition, TMC 18.06.935, includes manmade
channels if they convey natural water flows that existed prior to their construction.
Your wetland report indicates much of the drainage flowing through the site originates from the large forested
wetland directly south. The source of water appears to be natural groundwater discharges from adjacent
slopes.
3) As you know, the Planning Commission's hearing conditions for Reasonable Use must be adhered to in
order to allow the proposed wetland alteration. I have attached those conditions to this letter. If the
conceptual mitigation plan you submitted to them "is no longer valid" as stated in your letter, you are
encouraged to propose other potential mitigation and enhancement concepts. At this point, the Planning
Commission's conditions still need to be incorporated into an approved site plan.
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
•
Mr. Rodger Lacy
December 11, 1995
Page 2
Gary Schulz will need to review the mitigation/enhancement plan to verify that it is adequate and appropriate.
Staff supported your initial concept plan that did not intend to create new wetlands but would only enhance
those disturbed wetland areas on the site after your house is built. Therefore, we are not requiring you to
mitigate in a way that would expose you to possible legal liabilities. The information you provided staff and
the Planning Commission showed that you could enhance degraded wetland area on your property.
Per code standards (TMC Chapter 18.45), an enhancement ratio of 1.5:1.0 was proposed to occur on-site. If
you cannot meet this or other conditions set by the Planning Commission, a second hearing may be necessary
to consider modifications to the Commission's approval.
4) The time to submit the mitigation plan is related to the approval of the entire project. Any wetland area
filled, graded, or drained by the interceptor pipe system is considered a wetland impact. Watershed Dynamic's
wetland data map (see attached) indicates they surveyed the eastern half of your property and found wetland
conditions except for the old road.
The SEPA threshold determination can be completed after all on-site impacts and potential off-site impacts
are known or addressed. The requirement to install the mitigation enhancements prior to issuance of a
building permit is hearing Condition #4. The Department of Community Development has certain approval
authority but cannot change the Planning Commission's Conditions. Therefore, the wetland enhancement
must be installed during the building schedule.
5) Once again, regarding the application of RCW 36.70A.030 the opinion is that the wetlands on your site
are not "those artificial wetlands intentionally created from nonwetland sites". As support to this opinion, your
geotechnical consultant states on page 5 of the Geotechnical Investigation, Rodger E. Lacy Sr. Residence (The
Galli Group 3/15/95) "One of the dominant site features is the presence of several "watercourses" which
appear as shallow silt and gravel -filled swales meandering down the hillside. These drainageways appear to
have been altered by excavation in the past. Some of the water appears from sand or gravel seams in the
hillside and some may be the result of near surface or surface runoff from off-site. There are several areas
where the upper foot of soil appears wet much of the year".
You may disagree with any or all of the 5 responses listed above but they should answer the issues presented
in your 9/19/95 letter which is also attached. The background information that I understand from the staff
working with you is a concept site design was approved, with conditions, by the Planning Commission in April
1995.
The geotechnical peer review conducted through the Public Works Department concludes your site is suitable
to develop a single-family homesite. There may be unresolved drainage issues since that plan is not competed
for the home and new impervious surfaces. There has been no formal land altering, utility, or building
applications. We want to complete the SEPA Determination so you can move forward with your development
permits.
In order to finish the SEPA we need to know the extent of wetland filling, grading, and draining with proposed
mitigation. Most of the drawings you have submitted to the various departments since May 1995 indicate the
eastern portion of the site will be drained. It is not clear whether there will be any open water or wetland
areas on the eastern part of the property after site development.
• •
Mr. Rodger Lacy
December 11, 1995
Page 3
The site will be developed using the recommended engineering techniques and design features to insure safety
and stability. These design details are also necessary for the Land Altering Permit, Stormwater Plan Approval,
and ultimately the Building Permit. If you have submitted additional site plan details to Public Works, they
will be routed to Community Development for review. If you have questions regarding the contents of this
letter, please contact Vernon Umetsu at 431-3684.
Sincerely,
Steve Lancaster
DCD' Director
cc: Gary Schulz, Urban Environmentalist
Vernon Umetsu, Associate Planner
Ron Cameron, City Engineer
Joanna Spencer, PW Development Engineer
•
City of Tukwila
Department of Public Works
November 17, 1995
Mr. Rodger Lacey
4133 46th Ave. S.
Tukwila, WA 98188
Re: S. 158th Street Use Permit
Dear Mr. Lacey:
John W Rants, Mayor
Ross A. Earnst, P. E., Director
The City will write a street use/access permit to use S 158th Street with a gate as generally shown
on your plans. The two conditions would be that:
1. A future street improvement would require the relocation of a gate from about 51st Avenue S. to
where the future street and property line would be. (The owner would relocate the gate.) and
2. The City continue to use S. 158th Street as a maintenance access as normal.
Sincerely,
Ron Cameron, PE
City Engineer R EC E D V/ E D
RMC/mv
NOV 2 0 1995
COMMUNITY
DEVELOPMENT
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • Phone: (206) 433-0179 • Fax• (206) 431-3665
• •
MEMORANDUM
TO: File - Lacy Exception
FROM: Gary Schulz, Urban Environmentalist ,
DATE: November 16, 1995
RE: Telephone Meeting - Wetland Mitigation.
On Wednesday, 11/15/95, Mr. Rodger Lacy called me to discuss his
current site plan. The most recent drawing submitted to'date is a
"Site and Grading Plan" received on 10/4/95. The following points
were discussed during this conversation.
1) I told Rodger that we intended to send a response to his
9/19/95 letter sooner but the Director has been.extremely busy
with Council affairs. Also, Rodger had told staff he did not
need the letter immediately.
Rodger stated that the entire letter response was not as
important as agreeing to the mitigation area that will be
required for the project.
2) Rodger told me that his plan has changed because he will be
designing an open water detention pond instead of an
underground vault. I told him he could probably incorporate
this feature into his mitigation plan.
Rodger said he could mitigate on-site but wanted me to give
him a wetland area impact number so he could complete the
mitigation plan. My response to him was that we needed the
grading and stormwater plan details before determining the
total impact area. These sheet drawings are listed on the
cover of the current site plan but have not been submitted.
3) Rodger expressed concern over the time it was taking to
process this project due to environmental code and
geotechnical review. But.he understands that I need to look
at details before knowing the impact area and he will submit
them next week.
He then asked me to give him the number or would I "jack him
around" some more by waiting until the final peer review is
finished? I told him I would need to discuss this with the
Director as his plan keeps changing and he has not applied for
any permits. He thinks the mitigation plan needs to be
completed prior to permit application. I explained that is
not the normal process of steps to take to get the permits.
He stated that his consultants were very qualified and the
plan would not change further.
Memo - Lacy File
11/16/95
Page 2
4) Sometime during the conversation I asked if he thought the
State would turn back the driveway area that is currently used
for access and part of WSDOT ROW. His reply was that he
didn't have time to wait and prefers to use the City's ROW
even if it means having to replace a retaining wall.
Rodger then asked me if I was working at the City when the
Crystal Springs Park fence was installed along the ROW and did
the City mitigate for areas the fence crossed thru the
wetland.
I told him I was here and no we did not mitigate because trees
and other vegetation were preserved. There was very little
impact and we have provided wetland mitigation in other areas
of the Park. I told Rodger that I thought I would attend the
ROW vacation hearing and he objected. I expressed concern
that he would raise a question about the mitigation and I
wanted to be there to answer Council's questions.
He replied that he would not make an issue of it until the
City tried to make him mitigate wetlands within the ROW that
he needs to use for access to the new house.
In conclusion I told Rodger we would get the response letter to him
very soon that would also give him some direction to get the SEPA
completed. He did not raise any of the other questions that were
included in his 9/19/95 letter to the Director.
cc: Steve Lancaster, DCD Director
Vernon Umetsu, Associate Planner
FAX 913148728178 SHANNON & WILSON P01
• •
WSHANNON ENVIRONMENTALWINt=TILNCs
September 11, 1995
City of Tukwila
Department of Public Works
6300 Southcenter Boulevard, Suite 100
Tukwila, Washington 98188
Attn: Mr. Ron Cameron, City Engineer
St-Ja" car
RE: SLOPE STABILITY ANALYSIS REVIEW OF PROPOSED SINGLE-
FAMILY RESIDENCE DEVELOPMENT, 51ST AVENUE SOUTH,
TUKWILA, WASHINGTON
SEATTLE
HANFORD
FAIRBANKS
ANCHORAGE
SAINT LOUIS
DOSTON
RECEIVED
SEP 131995
TUPUBLIC WORKS
At your request,- we have reviewed the Supplemental Slope Stability Data Report, dated
August 9, 1995, by the Galli Group, Inc., for the proposed Roger E. Lacy, Sr. residence.
That data report was prepared in partial response to written comments that we submitted to
_: the City of Tukwila on the slope stability evaluation presented in the Geotechnical
Investigation Report for the property. We understand that our comments pertaining to
roundwater and surface water discharge at the site will be addressed in a separate
document.
Our review of the Supplemental Slope Stability Data Report consisted of an evaluation of
appropriateness and applicability of the supporting data, assumptions, and calculations that
were used in deriving factors of safety for static and dynamic (earthquake) conditions at the
site. No attempt was made to perform independent slope stability analyses. Information
that was available for this review included the initial Geotechnical Investigation and
Supplemental Slope Stability Data Reports prepared by the Galli Group, and geotechnical
investigations of the hillside performed in 1964 and 1966 by Shannon & Wilson for the
Washington State Department of Transportation.
The Lacy property is located immediately north of Crystal Springs Park and west of the cul-
de-sac at the end of 51st Avenue South, 'Il�kwila, Washington. It is identified as 'Tract 48
of Sunnydale Gardens, Division 1, Tukwila. The property is situated approximately half
way up the moderately steep northeast -facing slope of the Duwamish Valley to the south of
OO NORTH 3TH STREET • SUITE 100
P.G. BOX 300303
SEA 1 I LE, WASHINGTON 98103
206.632.8020 FAX 206.633.67.77
W-7039-02
FAX 913148728178 SHANNON & WILSON
City of Tukwila
Attn: Mr. Ron Cameron
September 11, 1995
Page 2
• •
SHANNON &WILSON, INC.
the Tukwila freeway interchange. This area lies within an extensive ancient landslide mass,
and subsequent, relatively small slope movements have occurred downslope from the
proposed development. Remedial measures to stabilize the area were implemented in the
late 1960s in conjunction with construction of I-5 and the interchange. These measures
included regrading of the upper slopes to 4 Horizontal to 1 Vertical (4H:1V) and
constructing rock buttresses, horizontal drains, an interceptor trench, and an asphalt -lined
surface ditch to redirect surface water from the slope.
Because of the property's location within both a seismically active area and a sensitive area
with respect to slope stability, we recommended in our initial review that the slope be
reviewed for static and dynamic earthquake loading, and that the data, assumptions,
evaluations, -and calculations used in these analyses be provided to the City for their review
before issuing a construction permit for the property.
The Supplemental Stability Analysis Data Report provides the assumptions, data,
evaluations, and calculations used in developing slope stability analyses for the site. The
report also addresses the slope stability issues that we raised in our review of the
Geotechnical Investigation Report. Generally, the soil parameters and the assumptions for
failure planes used in the stability analyses appear reasonable and appropriate. Applying
these soil parameters and assumptions, the Galli Group estimated a factor of safety under
static conditions of 1.S for the lower slope below the site. For their dynamic (pseudostatic)
stability analysis, • they assumed a magnitude 6.5 earthquake resulting in a lateral ground
acceleration 0.17g and applied this acceleration as a pseudostatic coefficient. Under these
conditions, the Galli Group estimated that the factor of safety for the lower slope is less
than unity, indicating that the lower slope would be unstable under earthquake loading
conditions. However, they also suggested that the slope would most likely fail
progressively, beginning near the bottom of the slope, with each successive failure plane
further upslope having a higher factor of safety, increasing to 1.6 for a failure that would
directly affect the proposed Lacy residence. We concur with the Galli Group that factor of
safety of 1.5 is generally considered adequate for static conditions, and a factor of safety of
1.2 under earthquake loading is generally considered adequate. However, the calculated
factor of safety for their dynamic analysis is highly dependent on the break point used to
P02
W-7039-02
FAX 913148728178
•
City of Tukwila
Attn: Mr. Ron Cameron
September 11, 1995
. Page 3
SHANNON & WILSON P03
• •
SHANNON 6WILSON, INC.
• distinguish between the lower strength bedding clays and higher strength, cross -bedded silts.
If this boundary is located higher upslope, the factor of safety will be lower.
In conclusion, we are in agreement with the soil properties and parameters used in the slope
stability evaluation. These parameters provide a static and dynamic factor of safety of 1.8
and 1.6, respectively, for a failure surface that directly underlies the proposed residential
site. In our opinion, these factors of safety are reasonable and exceed commonly used
criteria for stability evaluations. Therefore, these observations and conclusions provide a
basis to proceed with the development plans assuming the owner is willing to accept the
risk that a future earthquake could result in slope movement on the lower portion of the
property and that a progressive failure mechanism could possibly affect the slope further
uphill. It should also be recognized that a stability analysis at its best can only create a
model of the site based on assumptions and simplifications of ground conditions.
Therefore, regardless of the results of a stability analysis, there are inherent risks in
building on any hillside property in an area where landslides have occurred.
This review has been prepared for specific application to the project at this site, as related
to the geotechnical aspects discussed herein. Within the limitations of scope, schedule, and
budget, our review was conducted in accordance with generally accepted professional
engineering principles and practices in this area at this time. We make no other warranty,
either expressed or implied.
W-7039-02
FAX 913148728178
•
City of Tukwila
Attn: Mr. Ron Cameron
September 11, 1995
Page4
SHANNON & WILSON
•
SHANNON &WILSON. INC.
We appreciate the opportunity to be of service and trust this letter meets your needs.
Sincerely,
SHANNON & WILSON, INC.
9////9,(
Daniel N. Clayton, C.E.G., R.G.
Senior Associate
DNC:WPG:GRF/grf
W7039-02.LTR!W7039-1kd/lkd
P01
EXPIRES 10/3/.75—'
Gregory R. Fischer, P.E.
Principal Engineer
CITY OF T(WILA
6200 Southcenter Boulevard, Tukwila, Washington 98188
To. VVrn.or Amin7C
FROM: c/oa,, h62- ,51)/
DATE: VOLCM-
SUBJECT:
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MEMORANDUM
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(206) 433-1800
RECEIVED
SEP .: 51995
CUiVMui' iY'
DEVELOPMENT
D6.22l2Q-
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FAX TRANSMITTAL
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TUKWILA PUBLIC WORKS DEPT. - 6300 Southcenter Blvd, Tukwila WA 98188 - (206) 433-0179
09/18/92
• Engineering, Inc.
Engineers / Planners / Surveyors /'Environmental Specialists
RECEIVED.
' AUG 311995
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•
City of Tukwila
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
August 24, 1995
Mr. Rodger E. Lacy Sr.
4133 46th Avenue S.
Seattle, WA 98188
Re: Lacy Project, E95-0010: Area To Be Mitigated.
Dear Mr. Lacy:
Steve Lancaster has asked me to respond to your August 18, 1995 letter (attached) regarding
the proposed wetland impact calculation of 12,900 square feet. Based on Watershed
Dynamic's 11/4/94 Wetland Letter Report, your property is mostly wetland except for the
old road fill that enters the site. The wetland impact assessment needs to consider all
drained and filled areas related to developing the property. Your April 3, 1995 letter states
and illustrates the impact area will be 16,000 square feet. The wetland area within the City's
ROW east of the 51st Avenue S. culdesac may also need to be included in the impact
assessment and mitigation. I realize this 16,000 figure may not be as accurate as your
current assessment; however, Community Development cannot review and verify the wetland
impacts without a current site plan.
The SEPA determination cannot be completed until comments are received from Public
Works which is dependent on geotechnical peer review. The wetland mitigation plan should
wait until all design, access, and utility issues are somewhat resolved for a revised site plan
submittal.
In summary, it is more appropriate for you to submit a mitigation plan after you apply for
a land altering or building permit. I will be on vacation until September 9th so if you have
questions, please contact Vernon Umetsu at 431-3684.
Sincerely,
C, Er
C. GaryUSchulz
Urban Environmentalist
cc: Steve Lancaster, DCD Director
Vernon Umetsu, Associate Planner
Joanna Spencer, PW Development Engineer
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Far (206) 431-3665
Rodger E. Lacy Sr.
4133 46th Ave So.
Seattle, WA. 98118
August 18, 1995
Mr. Steve Lancaster
City of Tukwila
Director of DCD
6300 Southcenter Blvd. Suite #100
Tukwila, WA. 98188
RE: Lacy Project, E95-0010: Area to be Mitigated
Dear Mr. Lancaster.
RECEIVE®
AlJ6 2 21995
COMmuwi fY
DEVELOPMENT
One of the last items that must be agreed upon is how much wetland area that I
am impacting, in order to create a wetland mitigation plan. I had my
geotechnical engineer Paul Stoltenberg to do a study of my building site and he
determine the wetland impact area as best as he could. His assessment did not
include areas impacted inside of previous disturbed "upland" areas and areas
containing fill material but disturbance of land classified as "wet" by the wetland
delineation report dated 11/4/94 from Watershed dynamics.
It was determined that the impact of the building pad and all impervious surfaces
is approximately 12,900 square feet. If there is any disagreement or questions
as to our computations please notify me immediately, so as to resolve this issue.
Thank you.
Sincerely,
Rodg r Lacy Sr.
DRAFT
Mr. Lacy
RE: Lacy project, L95-001, E95-0010
Dear Mr. Lacy:
This letter is to update you on the status of your project since our meeting of June 15, 1995. First let
me go over what has been accomplished in reference to the project.
You purchased property which has wetlands and slopes with instability history, so the property is
significantly impacted by the City of Tukwila's Sensitive Areas Ordinance. Your intentions to develop a
single family residence on the property are significantly limited by the SAO. In meeting with City staff,
you were informed that an exception from the ordinance may be possible due to the constraints on
the property, so you applied for a reasonable use exception as described in the TMC 18.45.115.
To obtain the exception you have submitted numerous plans and a geotechnical report. On April 27,
1995, the Planning Commission granted you a reasonable use exception (with four conditions) from
the Sensitive Areas Ordinance. This exception grants you conditional permission to develop a single
family use within a sensitive area of Tukwila. Please note that a use permitted through a reasonable
use exception must also conform to the procedures of the sensitive areas overlay zone and be
consistent with the underlying R1-7.2 zoning regulations [TMC 18.45.080(h)].
You have also submitted for SEPA, environmental review to construct a single family residence on
lands covered by water [WAC 197-11-800(b)]. The SEPA checklist remains under review pending a
peer review of the geotechnical report you submitted. We received the peer review report yesterday
and the Public Works Department is continuing review of the report. The report brings up questions
regarding stability of the subject property. I have attached a copy of the report for your information.
Due to the complexity of this site, there are a number of issues that need to be resolved before the
environmental review can be completed, before building permit applications are submitted, or before
any work can begin on the site.
1. Stability Issues
2. Survey issues
3. Site Clearing Without Permit Approval
Mechanical site clearing has occurred on the site without an approved wetland enhancement
plan. This type of clearing was expressly denied by the City. Please be aware that any
damage to wetland areas will be required to be remedied with the final wetland enhancement
plan.
4. Wetland Enhancement
The final wetland enhancement plan needs to be agreed approved by the Director of
Department. of Community Development (DCD). This plan must conform to the sensitive areas
overlay zone regulations and the conditions of the reasonable use exception. Details of this
plan need to be worked out after the peer review of the geotechnical report.
5. Access
The Fire Department access requirement and the access to the site need to be resolved. I
understand that you have not given up on the possibility that the Washington State
• •
Department of Transportation (WSDOT) may grant you permission to use the adjacent
property for access. However,if you access the property by way of the unimproved right-of-
way for S. 158th Street, the Public Works Department will need to see grading plans for this
proposal, and any necessary retaining walls necessary.
6. Building Permit Application
As part of the normal requirements for a single family residential building permit, you will need
to submit a final site plan showing all impacted wetland areas, the building location, all paved
access areas, any required fire truck turnaround areas, utility easements, any existing
easements (eg. on-site well). You will also be required to submit a grading plan showing
existing and proposed grades, and final on-site wetland enhancement, a storm drainage plan
with storm drainage calculations. In addition, Public Works will require that you submit plans
for all necessary utility extensions and connections.
We should discuss these items and the geotechnical peer review report further at the meeting with
your technical people. I will call to arrange a meeting for the week of July 10 through July 14th, at
your convenience.
If you have any questions regarding the status of your project please contact me at 431-3670. I will
make every attempt to assist you in moving your project forward.
Sincerely,
Jack Pace
Senior Planner
C: Steve Lancaster
Ron Cameron
Joanna Spencer
Gary Schulz
Libby Hudson
Supplemental Slope Stability Data
Rodger Lacy Residence
51st Avenue. South
Tukwila, Washington
Ref No. L95-001
August 9, 1995
The Galli Group Inc.
13500 Lake City Way NE, Suite 202
Seattle, Washington 98125
206-363-6449
RECEIVED
AUG 211995
CUMIVUNITY
DEVELOPMENT
RECEIVED
AUG 11 1995
TUKWILA
PUBLIC WORT ss.>
i
THE GALLI GROUP
Geotechnical Consulting
City of Tukwila
Department of Public Works
6300 Southcenter Boulevard, Suite 100
Tukwila, WA 98188
Subject: Rodger Lacey Residence
51st Avenue South, Tukwila, Washington
Ref. No. L95-001
Attention: Joanna Spencer, Development Engineer
Ron M. Cameron, P.E.
01-1041-3
August 10, 1995
The attached report and backup data is intended to supplement our report, Geotechnical
Investigation for Rodger E. Lacey Sr., 51st Avenue South, Tukwila, Washington, dated
March 15, 1995. This report is intended to clarify stability analysis concerns raised by
Shannon & Wilson in their review of this project.
In providing additional analyses and data, we have contacted Shannon & Wilson to verify
more specifically which portions of our analysis needed clarification. We have also
provided a figure showing each successive failure surface generated in our analysis of the
subject property.
In our professional opinion, based on the reports by others and our independent slope
stability analyses, the subject residence, when constructed in accordance with our report,
will not adversely affect the stability of the subject property or adjoining parcels. Our
analyses indicated computed factors of safety against failure of greater than 1.8 for static
conditions and greater than 1.3 for pseudostatic, using a seismic coefficient of 0.17 g..
If you have any questions, please call at your earliest convenience
Respectfully Submitted,
THE GALLI GROU
Paul Stoltenberg, P.E.
Project Engineer
aXPIRES 17rl6 °N,
gise` diva
William F. Galli, P.E.
Principal Engineer
13500 Lake City Way, Suite 202, Seattle, Washington 98125 • (206) 363-6449 • Fax (206) 367-5611
Supplemental Slope Stability Data
Rodger Lacy Residence
51st Avenue South
Tukwila, Washington
Ref no. L95-001
August 9, 1995
City of Tukwila
Public Works Department
Joanna Spencer, Development Engineer
Ron M. Cameron, P.E.
Introduction
The following information is intended to supplement our report, Geotechnical
Investigation for Rodger E. Lacy Sr., 51st Avenue South, Tukwila, Washington, dated
March 15, 1995. The comments are in response to a letter from Ron M. Cameron, City of
Tukwila, to Mr. Lacy, dated July 5, 1995, requesting additional information as a result of
the peer review provided by Shannon and Wilson, Inc. Specifically, the letter requested
the following:
1. The top (first) paragraph requests the supporting data, assumptions and calculations
used in deriving the factors of safety.
2. The second paragraph requests a seismic stability analysis and the assumptions and
calculations be provided.
3. Explanation of why remedial Section C is not applicable and why the inclined bedding
plane orientation in Remedial Sections D and E is considered to provide greater
sloping stability than other bedding orientations.
4. Estimates of site specific groundwater and surface water discharge estimates, for
retention system design.
The remainder of this letter and attachments are intended to satisfy or address the above
requirements.
Item 1: Supporting data, assumptions and calculations.
As stated in our report, the slope stability data was compiled from Slope Stability
Investigation, Tukwila Interchange, for the Washington State Highway Commission, April
30, 1966, by Shannon and Wilson. A discussion of the conclusions of that report are
included in the Galli Group report. Shannon and Wilson relied heavily on extensive field
testing and a very thorough field investigation to evaluate the underlying soil conditions
and to arrive at their assessment of the mechanisms of failure for the slopes in the vicinity
of the Tukwila Interchange. The pertinent section discussing their evaluation is attached
to this letter (see Appendix A). If necessary, a copy of the entire report is available from
our office.
Shannon and Wilson indicated that soil index properties obtained from lab testing would
result in unrealistic assessments of the slope stability of the area, and their report provided
a fairly convincing documentation of that conclusion. They concluded the failure
mechanisms were controlled primarily by the bedding of the underlying silts and clays.
Through various assumptions and correlations with both field and laboratory data they
arrived at empirical values of the soil properties for the area, which were considerably
more conservative (i.e. allow for higher probabilities of slope failure) than those obtained
through typical laboratory or field testing. Many of these assumptions were obtained by
observing actual failure planes of slides within the slope. We concluded that these were
reasonable assumptions, and utilized their data to arrive at our assessment of the stability
of the lower slope.
For illustrative purposes we have included a slope stability analysis (see Appendices B and
C) of the slope between Mr. Lacy's property and the 0 -line (off -ramp from SR 518). The
slope information is based upon boring information supplied in the Shannon and Wilson
report. Utilizing PCSTABL5, a slope stability program developed by the Purdue
University, and soil index properties from the Shannon and Wilson laboratory test results,
we performed a slope stability analysis of the slope. The results indicate a factor of safety
of approximately 1.8 for the slope under static conditions. The factor of safety determined
by the Shannon and Wilson analysis is provided in Figure 7.6 of Appendix A. Since
Shannon and Wilson's analysis included a very thorough field investigation and
incorporated impacts of remedial efforts, we utilized their estimates of factor of safety in
our initial report.
The factors of safety for the various remedial efforts were derived using the assumptions
shown on Figure 7.6. These were used for comparing the relative degrees of improvement
provided by the various remedial efforts. We concluded that these factors of safety likely
represent conservative assessments of the slopes below the Lacy property. In light of the
Shannon and Wilson analysis, and our field observations, we concluded that the slopes
below the Lacy property, subsequent to the remediation, appear stable.
From that point, our attention shifted to making sure that the proposed improvements to
the Lacy property did not compromise the global stability of the hillside.
1041ADDM.DOC 2
Item 2: Seismic stability.
We agree with the conclusions of the Shannon and Wilson report, that the underlying
dense silts and sands are not highly susceptible to liquefaction. In Appendix B we have
included a slope stability analysis for the Lacy property and lower slope analyzed under
pseudostatic conditions for a lateral ground acceleration of 0.17g. A discussion of the
assumptions, method of modeling, and conclusions is included in Appendix B.
Based upon this analysis, under seismic loading, the lower slopes may experience some
shallow surficial failures which could progress upslope if not remediated. However, these
are not anticipated to be deep seated failures of the hillside nor would they likely impact
the Lacy property. Factor of safety for the progressive failure which could impact the
Lacy property was calculated at 1.6. Generally a factor of safety of 1.2 under seismic
loading is considered adequate. Provided remediation for these failures is supplied, (which
would seem likely since the interchange may be impacted) upslope progression of the slide
would not likely encroach on the Lacy property. Again, this analysis is intended to
provide some gauge as to potential impacts on the slope, based upon the assumptions
described in Appendix B. Actual factors of safety may be larger because of the variable
bedding planes within the clayey silt unit underlying the lower reaches of the slope.
Item 3: Remedial Section C
Remedial Section C was not considered primarily because it does not include the Lacy
property except for a small southeast corner. The existing topography slopes away from
the Lacy property toward the north. However, the factors of safety for Section C are
provided in Figure 7.6 in Appendix A. Similar to the other sections, this factor of safety
was computed using the soil properties shown. Since structures existed above the W -line,
the Shannon and Wilson analysis and remedial efforts would have provided a factor of
safety of at least 1.5.
The discussion in our report regarding the inclined bedding planes was adapted from the
investigation performed by Shannon and Wilson. They concluded that the inclined
bedding planes contributed toward the failure mechanisms of relatively recent (prior to
1966) slide activity in the hillside. Their comments and observations from observing the
bedding inclination of field samples indicated that the area near the "point" (due north of
the Lacy property) consisted of bedding planes dipping in non-uniform directions. They
also concluded that since the planes did not dip downslope, the area would tend to be
more stable than in other areas, where bedding planes dipped in the direction of potential
slope movement. Since, the bedding planes appeared to have significant impact on slope
failures where slides did occur, we concluded that anisotropic soil conditions resulting
from bedding planes dipping into the hillside or across the hillside would likely improve
stability compared to other locations.
1041ADDM.DOC 3
Item 4: Groundwater and surface water discharge
Most of this will be addressed at a later point of review, when the stormwater
retention/detention plans are provided. Two general statements can be made at this point.
First, the impervious areas are planned to drain toward a retention system with a
controlled outlet. These should not increase the rate of discharge from the site.
Secondly, the interceptor trenches are relatively shallow (less than 5 feet). They do not
intercept any groundwater aquifers. Near surface flow intercepted by the trenches will be
directed to the same outlet where these near surface flows currently discharge, the asphalt
lined swale. The difference in quantity and time of concentration is not anticipated to
result in any significant increase in rate of discharge from the design storm events. This is
discussed more fully in the site and grading plan to be submitted with the building plan set.
We agree with the City of Tukwila in their call for "extreme care" associated with
development in this area. We have relied heavily on the thorough subsurface investigation
of a very reputable geotechnical firm, Shannon and Wilson, Inc., in arriving at our
assessment of the characteristics of the slope. We have concluded, with them, that the
remediation efforts associated with the construction of the Tukwila Interchange, have
adequately stabilized the hillside below the Lacy property. Subsequent monitoring of the
slope in the immediate vicinity of the Lacy property during construction and after has not
indicated any signs of significant slope movement. The addition of a single family
residence, provided the measures emphasized in our report are followed, does not appear
likely to compromise the current stability of the hillside.
Respectfully submitted,
Paul L. Stoltenberg, P.E.
Project Geotechnical Engineer
Attachments: Appendix A: Correspondence and Section 7, Shannon and Wilson Report
Appendix B: Discussion of Slope Stability Analyses
Appendix C: Supporting Data for Stability Analyses
1041ADDM.DOC 4
Appendix A
Section 7, Shannon and Wilson Report
Correspondence
August 9, 1995
Supplemental Slope Stability Data
Rodger Lacy Residence
51st Avenue South
Tukwila, Washington
The Galli Group Inc.
13500 Lake City Way NE, Suite 202
Seattle, Washington 98125
206-363-6449
JUL 06 '95 04:47PM TUKWILA DCD/PW P.2
July 5, 1995
City of Tukwila
Department of Public Works
Mr. Rodger E. Lacy, Sr.
3125 Dakota Street
Seattle, Washington 98108
RE: Lacy Project, L95-001, E95.0010
Dear Mr. Lacy:
John W. Rants, Mayor
Ross A. Earns P. h, Director
You called Wednesday, July 5, 1995 inquiring about the Shannon and Wilson peer review of Galli's geotechnical report and
requesting a copy of the Crystal Springs mapping showing the fence line. The Shannon and Wilson report is attache.
Page 5 identifies four areas where additional information is needed
1. The top (first) paragraph requests the supporting data, assumptions and calculations used in deriving the factors of
safety.
2. The second paragraph requests a seismic stability analysis and the assumptions and calculations be provided.
3. Explanation of why remedial section C is not applicable and why the inclined bedding plane orientation in Remedial
Sections D and E is considered to provide greater sloping stability than other bedding orientations.
4. Estimates of site specific groundwater and surface water discharge estimates, for retention system desk.
Please return this information to Development Engineer, Joanna Spencer.
The Construction Engineer returns from vacation next week. Upon his return, the Crystal Springs drawings will be
forwarded to you.
As explained in previous conversations, this area has a significant history of geotechnical problems. We've experienced
them with the park construction, and street construction. They continue to remind us of the need for extreme care.
Sincerely,
Ron M. Cameron, P.E.
City Engineer
RMC/ed
enclosure: June 26, 1995 Shannon and Wilson report
of: Steve Lancaster, DCD Director
Joanna Spencer, Development Engineer
ronlacy.doc
6300 Sounccenter Boulevard, Suite #100 • Tukwila, Washington 98188 • Phone: (206) 433.0179 • Far (206) 431-3665
JUL 06 '95 04:47PM TUKWILA DCD/PW
P.3
SHANNoNW1LSoN INC, SEATTLE
} HANwOR7
MEW II GEOTECHNICAL AND ENVIRONMENTAL CONSULTANTS CNK•
ANCHORAGE
SANT LOUIS
BOSTON
June 26, 1995
City of T1hkwila
Department of Public Works
6300 Southcenter Boulevard, Suite 100
'llikwila, Washington 98188
Attn: Mr. Ron Cameron, City Engineer
RECEIVED
JUN 281995
PUBLIC
RE: GEOTECHNICAL REVIEW OF PROPOSED SINGLE-FAMILY RESIDENCE
DEVELOPMENT, 51sr AVENUE SOUTH, TCKWILA, WASHINGTON
This letter presents the results of our review of the proposed Roger E. Lacy, Sr. residence,
Tract 48 of Sunnydale Gardens, Division 1, in the vicinity of the 51st Avenue cul-de-sac,
Tukwila. In accordance with your request, we have conducted a geotechnical review of the
suitability of this property for development of a single-family residence. Specifically, we
have attempted to address the following issues identified in your letter of May 18, 1995:
► Is the property affected by the same deep slide plane as the proposed Hillcrest
Development (located to the southwest along Slade Way)?
` ► Are there any geological concerns for a house on the Lacy property?
• Are there any drainage concerns to address, and specifically, is the plan sufficient
relative to the adjacent Washington State Department of Transportation (WSDOT)
system?
For this review, you provided us with a geotechnical report for the subject property dated
March 15, 1995, prepared by the Galli Group, as well as copies of several reports and
supporting documents pertaining to the Hillcrest Development.
SCOPE OF WORK
The scope of our services consisted of a site visit and visual reconnaissance of the Lacy
property by Mr. Dan Clayton on June 19, 1995; review of a geotechnical report that was
prepared for the subject property by the Galli Group in March 1995; and review of Shannon
400 NORTH 34TH STREET • SUITE 100
PO. BOX 300303 W-7039-01
SEATTLE, WASHINGTON 86103
206.632.8020 FAX 206.633.6777
T00: 1.800.833.6388
JUL 06 '95 04:4BPM TUKWILA DCD/PW P.4
City of T kwila
Attn: Mr. Ron Cameron
June 26, 1995
Page 2
SHANNON WILSON.INC.
& Wilson files pertaining to geotechnical investigations of the area that were performed for
WSDOT during the 1960's. The reports and supporting documents for the Hillcrest
Development were briefly reviewed, but are not considered directly relevant to the geologic
conditions at the Lacy property.
SITE CONDITIONS
The Lacy property is located immediately north of Crystal Springs Park and west of the cul-
de-sac at the end of 51st Avenue South, kwila, Washington. The property is situated
approximately half way up the moderately steep northeast -facing slope of the Duwamish
Valley to the southwest of the Tukwila freeway interchange. It is an elongate plot,
approximately 150 by 600 feet in dimension, bounded' on the south by Crystal Springs Park,
and on the north, west, and east by undeveloped land. The site is currently undeveloped,
partially cleared and partially covered with blackberry bushes, alder trees and a few maple
trees. Some of the clearing appears to have been accomplished very recently, as there was
no vegetation growing on what appeared to be freshly turned soil at the time of our visit.
The property has a total of over 70 feet of relief, with a steep slope on the western end of
the site and a moderate slope extending from the base of the steep slope to the eastern end
of the property. At the time of our site visit, there was a considerable amount of surface
water flowing across the site, mostly along shallow ditches that have been constructed to
provide site drainage. Some of these ditches flow into a larger ditch constructed along the
northern property boundary, and all appear to flow ultimately to an asphalt -lined ditch near
the eastern end of the site. This surface water is derived largely from seepage at or near
the base of the steep slope near the western end of the property, although some surface
water probably flows onto the site from further upslope, especially during the rainy season.
The upper, western half of the site is underlain at the surface by loose sand that appears to
be old landslide deposits or colluvium derived from the steep slope on the western end of
the site. Pill materials consisting primarily of sand and silty sand cover much of the lower,
eastern half of the site. The natural surficial soils in this area include both sand and clayey
silt. According to the geotechnical report, the owner wishes to build on the lower, eastern
part of the site in an area that is partially mantled by old fill materials.
W-7039-01
JUL 06 '95 04:49PM TUKWILA DCD/PW P.5
City of Tukwila
Attn: Mr. Ron Cameron
June 26, 1995
Page 3
SHANNON SWILSON, INC.
The steep slope that crosses the western end of the property is interpreted as the headscarp
of an ancient landslide, with all of the material to the east of it occupying the downdropped
block of the slide. There have been numerous smaller landslides within this ancient
landslide mass, many of which were associated with the construction of the ThIcwila
Interchange at the foot of the hill during the 1960's. Most of these smaller slides were
remediated by WSDOT in the mid -1960's as part of an extensive hillside stabilization
program. No evidence of recent sliding was observed on or adjacent to the site during our
reconnaissance.
.DISCUSSION
The geotechnical report prepared by the Galli Group is based on a site reconnaissance;
activation of five test pits in the area where the residence is proposed to be constructed;
and a review and evaluation of subsurface information, geotechnical evaluations, and
remedial measures implemented by WSDOT approximately 30 years ago as part of an
extensive program to stabilize the hillside above the Tukwila Interchange and Interstate
Highway 5 . The report provides recommendations for slope stability, foundation design,
grading and earthwork, and site drainage, based on the proposed construction of a two-
story, wood -frame, single-family residence on the eastern half of the property.
It is our opinion that the Galli Group report generally provides appropriate geotechnical
recommendations for measures that will be required to successfully develop this property.
However, with respect to their evaluation of scope stability, the report appears to rely
heavily on evaluations that were performed thirty years ago for a somewhat different
purpose. Unfortunately, the Galli Group report does not provide the data and assumptions
that were used in developing their conclusions regarding slope stability, so it is not possible
to provide an independent evaluation of the applicability of those slope stability evaluations
to present-day site conditions. Moreover, it is not clear from their report whether the Galli
Group accepted the factors of safety for slope stability provided by the 1964 Shannon &
Wilson report, or whether they re-evaluated the data, assumptions, and calculations used in
establishing those conclusions based on present-day conditions for the purpose of this
development. In our opinion, such a re-evaluation would be appropriate, considering the
potential for changed conditions over the intervening 30 years.
W-7039-01
City of 7Lkwila
Attn: Mr. Ron Cameron
June 26, 1995
Page, 4
SHANNON 6WILSON, INC,
Perhaps as a result of the lack of supporting data for the stability analyses, there are also a
few apparent discrepancies or omissions in the Galli Group's report with respect to their
conclusions about the hillside stability. In particular, it is not clear (a) why the inclined
bedding shown in Remedial Sections D and E (Figures 3A and 33) is considered to enhance
the slope stability of this area, (b) why a dewatering system would have been installed in
the first place if the factor of safety without it was 1.9, and (c) why Remedial Section C
should not also be considered in assessing the stability of the eastern part of the site.
With respect to drainage provisions, the Galli Group report states that adequate drainage
will be a critical factor in the preparation of the site for construction and will help to
increase the local and global. stability of the hillside. Accordingly, they provided
recommendations for placement and construction of drainage measures, apparently including
a storm water retention/detention system. However, little is actually said about the storm
water retention system design other than a recommendation that it be a closed system (not
surface ponding) to reduce the likelihood of a cataclysmic discharge of water to the hillside.
There is no mention which, if any, of the site drainage systems will be tied into the storm
water retention/detention system and how that system will be sized to accommodate peak
flows from groundwater and surface water. We believe that this will be an important
design consideration that will have to be addressed in order to comply with WSDOT's
prohibition of increasing peak discharge to their hillside drainage system.
FINDINGS AND RECOMMENDATIONS
In general, the geotechnical investigation that has been performed and the recommendations
that have been provided for the Lacy property appear to be adequate and appropriate for the
type of development that is proposed. The largest single concern for the property is slope
stability because it lies within an extensive ancient landslide mass that has been subjected to
subsequent, relatively small movements on the slope below the site. Based on the lack of
recent slide movements and an evaluation of slope stability, the owner's geotechnical
consultant concluded that the hillside has apparently been stabilized by WSDOT remedial
measures that were implemented in the mid -1960's. Specifically, they concluded that, for
the most probable mode of shallow and progressive failure, the slopes below the site have
been effectively stabilized (by remedial measures performed about 30 years ago).
T ' d
W-7039-01
Md/QEQ t11IM>illl WdBE :80 SE, L0 inr
City of Tukwila
Attn: Mr. Ron Cameron
June 26, 1995
Page 5
SHANNON (WILSON. INC.
Based on their evaluation, the Galli Group provided factors of safety for static conditions
for the site that are generally considered adequate for residential development. Although
their findings appear to be reasonable, the supporting data, assumptions, and calculations
used in deriving the factors of safety are not included in their report. It is our opinion that
the data, assumptions, evaluations, and calculations used in deriving the factors of safety
should .be provided to the City for their review before issuing a permit for the property
development.
The Galli Group concluded that dynamic loading need not be considered in evaluating the
stability of the proposed development, and apparently based this conclusion on a statement
made in a 1964 Shannon & Wilson report for WSDCIT. Considering the increased concern
for seismicity in the Puget Sound region that has developed since 1964 and the location of
this site in an area that has loose soils and landslide potential, we believe that a seismic
stability analysis should be performed for the property and that the assumptions and
calculations used in this analysis should be provided for the City's review.
Along with the supporting information for stability analyses, the owner's geotechnical
consultant should explain why Remedial Section C (shown in Figure 3 of the Galli report) is
not applicable to the eastern part of the site, and why the inclined bedding plane orientation
shown in Remedial Sections D and E (Figures 3A and 3B) is considered to provide greater
slope stability than other bedding orientations. This is particularly true if this bedding
orientation has been used in the assumptions for their stability analyses,
Apart from potential slope stability issues, there do not appear to be any significant geologic
constraints or drainage issues that could not be addressed in the geotechnical design and
development of the site. However, site-specific groundwater and surface water discharge
estimates will be necessary to size an appropriate storm water retention system capable of
retaining the peak storm water runoff once the basic building design has been established.
In our opinion, the timing for submittal of this information is not critical as long as the
owner is aware of the design requirements that will be needed to address WSDOr- imposed
peak discharge restrictions.
•
City of Tukwila
Attn: Mr. Ron Cameron
Tune 26, 1995
Page 6
SHANNON toWILSON. INC.
LIMITATIONS
This letter report has been prepared for the City of Tukwila in accordance with generally
accepted professional engineering principles and practices, for use by the City of Tukwila in
review of the proposed Lacy single-family residential development at 51st Avenue South,
Tukwila. No other warranty, either expressed or implied, is made as to the nature of the
conclusions and recommendations. The content of this report is not intended for the use of
other parties or for other purposes. It may or may not contain sufficient information for
other uses. Shannon & Wilson, Inc. has prepared the attached "Important Information
About Your Geotechnical Report" to assist you and others in understanding the use and
limitations of our reports.
We appreciate the opportunity to be of service.
Sincerely,
SHANNON & WILSON, INC.
Daniel N. Clayton, R;G., C.E.G.
Senior Associate
DNC:WPGIdnc
W. Paul Grant, P.E.
Vice President
Enclosures: Important Information About Your Geotechnical Report
V;7039.01.LTI PK7039.1kdleet
E'd
W-7039-01
Md/ax b1IM>i61 Wb6E :80 S6, 2 inf.
PART 7
EVALUATION
A. INTRODUCTION
Prior to the start of the field exploration program in January, 1966, and
the related slope stability investigation, a surface reconnaissance was conducted
in an attempt to determine the extent of studies that would be required for a
comprehensive engineering evaluation. This reconnaissance included the inspec-
tion with personnel from the State of the entire project area. At this time,
December, 1965, a sketch map was prepared, which roughly located the extent
of the various slide masses. From surface observations only, engineering hypo-
theses were then developed with regard to the mode of failure for each indentifiable
slide area. In addition, the previous studies were reviewed, so that there would
be little or no duplication of effort in the present study. Based on this reconnais-
sance, we proposed a program of investigation, which was presented in our letter
report of December 23, 1965.
The actual conduct of field exploration was oriented to the collection of
information, which could be directly utilized in our engineering evaluation of the
present -conditions and probable post -construction conditions. This evaluation
comprised an investigation of the causes and mechanisms of the earth movements,
an evaluation of the stability of both the failed slopes and proposed slopes under
various assumptions, and consequent recommendations for remedial measures.
Previous investigations in this area have been utilized to supplement the
field data obtained in the present study. In addition to the material included in
the various reports, a number of the older field instruments were -utilized to good
advantage.
The earliest report available, dated June 27, 1961, was prepared by Dames
& Moore and describes the Slade Way slide. Soils data obtained from four
boring logs given in their report have been used in the
preparation of Profile 2,
Fig. 5.2. In addition,
Slope Indicator observations were utilized from their
report for locating the old slide failure surface.
Soils information obtained from two previous Shannon & Wilson, Inc.
reports, dated June 12 and July 14, 1964, was also utilized in the development
of the Generalized Soil Profiles, Figs. 5.2 through 5.6. These two reports cover
an area which extends from the southerly limits of the Slade Way slide to 51st Ave.
S. at the westerly extremity. Many of the piezometers and Slope Indicators
utilized in these reports were recovered and are being observed on a regular
basis. In addition to the field data, the engineering studies and recommendations
were reviewed in light of the data and observations which have been made on the
slope failures that have occurred to the west of 53rd Ave. South.
Where appropriate, reference is made to a number of other reports,
technical papers and books (see Bibliography) which deal with the subject of
slope stability in overconsolidated clays and silts.
B. SLOPE STABILITY COMPUTATIONS
Slope failures in the fissured and slickensided silty soils in the area are
progressive, and as movement occurs, the strength of the material is radically
affected. • The use of conventional types of stability analyses leads to unsatis-
factory conclusions regarding the factor of safety of the slopes. Hence, the
more significant conclusions in this study were drawn on a semi -empirical basis.
However, the data obtained from the field and laboratory testing programs made
it possible to perform a number of simplified stability analyses which provided
rational limits for the relative comparison of various remedial measures.
Mathematical simplifications, based on observations and resulting
assumptions derived from the field explorations, together with our best engineer-
ing judgment, have provided a reasonable basis for developing quantitative data
from stability analyses. Therefore, the results are dependent upon the validity
of the assumptions and simplifications, and should not be considered as exact
solutions. Possible variance between real and assumed conditions should always
be kept in mind. The principal use of a mathematical or approach tical
Y � is
that it provides a means for making a relative comparison of certain remedial
measures with the corresponding increases in stability (i.e. , comparing factors
96
of safety before and after), rather than attaching any particular significance to
the actual values of the factors of safety themselves.
At least one (and generally more) stability analysis was performed for
each remedial section. These sections are located in the Plan of Recommended
Remedial Measures, Fig. 7.1 and shown in generalized profiles, Figs. 7.2
through 7.5. In each case these analyses were re -computed for varying assumptions
regarding groundwater, cut slopes and restraining measures.
Since most of the slides appear to have failed along planar or parallel
"stair -step" failure surfaces, a sliding -wedge type of analysis was used.
Hydrostatic pressures were assumed, based on available piezometer data. The
locations of the failure planes were determined from geologic observations, Slope
Indicator data, inclinometers, test pits, and slide movement stakes.
Stability analyses for existing slopes before failure and for proposed
construction slopes were performed using assigned hydrostatic pressure gradients
which best satisfied observed conditions in the field, assuming the slopes have
a factor of safety equal to unity. For those slopes west of the cul-de-sac, which
have already experienced failure, this calculation (assuming no cohesion) indicates
an angle of shearing resistance on the order of 14°. Since this value is also in
agreement with the angle obtained from the laboratory torsion shear tests on the
silty clay laminae, this angle of shearing resistance was used in subsequent
slope stability analyses where failure occurred principally along the dip of the
bedding planes. For failure assumed to occur across dip (hence, across layers
of clayey silt) an angle of 25° was used. This value is consistent with the large-
scale field torsion shear tests and also with the values used for previous studies
completed in this area.
A general summary of our slope stability analyses is presented in Fig. 7.6.
The relative importance of the values shown is discussed with respect to each
remedial section in subsequent paragraphs. Seismic loading has not been included
in the stability analyses, although Seattle is in an active seismic zone. There
are two reasons for not including seismic effects:
1) The strength parameters of the clayey silt used in the stability
analyses are ultimate strengths based on a progressive failure hypothesis. For
seismic loading, the strength parameters would be greatly increased and the
net effect would be a computed increase in factor of safety.
2) The sands and gravels although saturated, are dense and would
not liquify under reasonable assumptions as to duration and magnitude of
earthquake.
In 1948 and again in 19 65 , the Seattle area was subjected to strong
earthquakes. There are documented cases of liquifaction in the old tidal flats
and in loose, saturated fills, but to the best of our knowledge there were no
slope stability problems in stiff, over -consolidated clays and silts, nor in
dense outwash sands and gravels.
C. REMEDIAL MEASURES
Our remedial recommendations have been condensed and summarized on
a plan sheet, Fig. 7.1. The entire project area has been subdivided into eight
remedial sections, Figs. 7.2 through 7.5, designated A through H on the plan.
In general, the limits of these remedial sections are defined by changes in sub-
surface conditions or changes in method of remedy. The related cross-sections
show a general scheme for remedial construction, whereas the summary table on
each section more completely defines the limits of each recommended procedure.
1. Remedial Section A
This section encompasses an area below Slade Way, which extends
from Sta. Lw -2529 on the south to Sta. W-101+75 on the north. Three features
are of primary concern in this area: 1) the existing 60 -inch diameter, City of
Seattle high-pressure water main, 2) the high artesian water pressures in the
subsurface sands, and 3) the proposed 40 to 59 -foot deep W -Line cut.
a. Present conditions
In general, Remedial Section A is located in an area influenced
by high artesian pressures in dense sand strata underlying a varying thickness of
97
clayey silt. In addition, it is an area which has a history of recent
(1960-1964)
slide activity. However, there has been no indication of major slidemovements
since the deep -well pumps were placed in around-the-clock pumping
The Dames & Moore report (1961) defines a failure surface that is w operations.
clayey silt, in close proximity to the sand -silt contact. thin the gray,
Based on our 1964 recommendations, with field modification,
24 deep -well pumps were installed along the head of the proposed
These wells were designed for the dual purpose of relieving the high artesian cut.
pressures in the underlying sands and draining the overlying silts. artesian
discussed in Part 6, field observations indicate that the wells are functioning
As
as designed, except that water -level observations are nc °n the
gray silt. This variability appears to be a function of the layered strratic ructure, the
which creates perched water tables. cture,
In our opinion, as a result of the relatively
wide well spacing (60 to 70 feet between each series of three wells
are not fully effective in draining these perched conditions. ) the pumps
Additional drainage has been provided by a perforated under -
drain, designated as D-3 on Fig. 7.1. The pump water is drained o
by means of an existing asphalt -lined ditch and sewer system. Numerous
u e ouf hori-
the slope
zontar drains have been installed in the slope at the southern extremity of Section A.
At some time after the apparent stabilization of the Slade Way
slide, the 60 -inch, high-pressure water main was installed. It is ou
ing that the top -of -pipe elevation is approximately
understand-
ing
10 feet below the ground
surface at the W -Line. It is reported that this main was constructed us'
pre-
cast concrete segments, which can tolerate no more than 1/4 inch of differ per pipe segment, ential
The proposed W -Line cut is now designed to have a maximum
depth of about 45 feet, with cut slopes which vary from 2:1 to 2.5:1
excavation of the cut, it was planned that horizontal drains would be iter
to intercept the vertical wells, thus converting them to gravis fl alled
would then be turned off. Y ow. The pumps
Surface inspection showed no indication of major active
slides, although some minor sloughing was noted near the toe of the sloe.
Slope Indicator observations suggestp
movements have occurred during he past few months.some Howevr, these
relatively small random ground
are not slide movements, because they do not show a progressive downapParently l
l
movement. As stated previously, they are probably a result of a change in
internal stresses due to the drawdown of the groundwater table.
b. Recommendations
Remedial measures recommended for Section A are intended
to provide: 1) stable cut slopes,
A 2) permanent support for the area uphill from
the W -Line, 3) lateral support for the 60 -inch water main, and 4) permanent
gravity drainage for the relief of artesian and seepage pressures
It is recommended that the area between the existing Group 1
pumps and the uphill W -Line roadway ditch be re -graded to a slope varying from
3:1 to 4:1, with the flatter slopes being near the 60 -inch water main, as
summarized
in detail in Fig. 7.2. The area to the east of the uphill W -Line ditch may be
leveled off, but not excavated to the planned roadway elevation until com let'
of the retaining structures recommended below. ' P ton
As shown in Figs. 7.1 and 7.2, approximately 550 lineal feet
of cylinderpile retaining wall has been recommended. This wall will not only
permit the slope flattening to be accomplished but also should provide
retention of the sandy soils in the W -Line cut. This
positive
in the event that the recommended drainage beco es ineffective particular importance
at some time
in the future. A cylinder pile type of wall will also permit the construction of all
remedial measures, except for drains which tap the vertical wells
excavation for the roadwaycut. prior to
The wall will be located on the uphill side of
the W -Line roadway ditch and its height will vary from about 15 to 20 feet above
the ditch line. It is presently anticipated that 4 t� 5 -foot diameter cylinders w
be used for the wall. The cylinders should be designed to retain an equivale .111
fluid pressure (E. F. P.) equal to at least 60 nt
pounds per cubic foot (p. c.f.). This
1
98
recommended E.F.P. takes into consideratiorr that there will be lateral loads
imposed by a rock -fill buttress, which is to slope upward from the top of the
wall. The E.F.P. value of 60 p . c . f . was determined on the basis of the
following relatively conservative assumptions for the sand and rock behind the
wall: 0 = 40°, c = 0, unit weight = 150 p. c. f. , Ka (Rankine) = 0.4 and a 1.5:1
infinite slope extending back from the wall. This wall will develop most of its
passive resistance within the dense sands, which are present below the W -Line
roadway, but which also will be below the permanent water table. Because of
this, the cylinder wall should be designed so as not to exceed a maximum passive
soil pressure (q0) equal to 1.0 tons per square foot (t. s.f.) at the depth of the
X -X line. This pressure may increase at the rate of 0.2 t. s. f. per foot of depth.
The coefficient of horizontal subgrade reaction (kh) should be taken as equal to
zero at the X -X line and may be increased at the rate of 60 pounds per cubic inch
per foot of depth. These design recommendations are shown in Detail C, Fig. 7.2.
For purposes of design the amount of wall deflection is not critical, because the
previous slide movements have probably relieved any "locked -in" horizontal
stresses, similar to those which have caused severe problems on other Seattle
sites. In our opinion, deflections as large as 4 to 6 inches would be tolerable,
except immediately adjacent to the 60 -inch water main. To prevent the build-up
of hydrostatic pressures behind the wall, drainage facilities should be provided.
We further recommend that a rock buttress be constructed above
the cylinder wall as shown in Fig. 7.2. This rock mass is designed to provide a
strong passive toe for the slide mass as defined by the Dames & Moore report.
This is necessary, (from our interpretation of the soils data presently available)
because the failure plane of the dormant Slade Way slide apparently daylights at
an elevation somewhat above the design top -of -wall elevation. For purposes of
stability analyses it was assumed that the rock fill would have an approximate
unit weight equal to 150 p. c. f. and an average shearing resistance (0) equal to
45 degrees. The main criteria for the rock fill material is that it should be free -
draining and contain angular pieces having an approximate size of 6 inches, with
no materials smaller than sand -size. Excavation for the foundation of the buttress
should be made in 50 -foot segments and backfilled with rock prior to cutting of
the adjacent segment. The rock fill should be dumped and spread into 1 to
2 -foot lifts and traffic -compacted by the haul trucks and spreading dozer. The
height of the buttress will vary, as shown in Detail B, Figs. 7.2, but should be no
less than equal to the height of the exposed portion of the wall. The final height
should be determined in the field after the slope has been graded and the sand -
silt contact more clearly defined.
After completion of the cylinder wall and buttress construction,
the final excavation may be made. This can then be followed by the installation
of horizontal drains to tap the existing deep wells. These drains should be drilled
on an approximate grade of 1 percent. If the flow is extremely heavy (close to
full pipe) in certain drains, we suggest that a second horizontal drain be drilled
into the same vertical well. These drains may be of perforated plastic pipe,
except for the final 10 feet at the discharge end which should be of solid pipe.
Near the face of the wall, the annular space between the outside of the drain
pipe and soil should be sealed with quick -setting cement grout. This will prevent
flow around the outside of the pipe, which could cause "piping" .
To improve the drainage in the gray silts, we recommend that
16 vertical drains be drilled and installed in line with and between the existing
deep -well pumps (see Fig. 7. 1) . These additional drains may be drilled with a
small -diameter hollow -stem auger. The depth should be sufficient to reach the
relatively clean sands, but in any case they need not be deeper than the existing
wells. No pumps will be required in these drains. Prior to removal of the auger,
a perforated plastic drain pipe should be set inside the hollow stem. As the auger
is removed from the hole, the annular space outside of the pipe should be back-
filled with free -draining, granular filter material. In theory, water will drain
from the gray silts into the vertical drains, and thence down into the underlying
sands. Since the expected flow from the silts is relatively small, there should
be no tendency for these drains to recharge the sands, which are in turn drained
by either the existing pumps or the recommended horizontal drains.
TUKWILA INTERCHANGE
99
:
The suggested remedial measures discussed above should
provide permanent protection for Remedial Section A. To assure a reasonable
amount of safety to the existing slope, uphill property, and the 60 -inch water
main, the State should closely control the contractor's sequence and method of
construction.
c. Relative stability
Based on various assumed groundwater conditions, the Slade
Way slide would have a factor of safety (F.S.) somewhat less than unity, if none
of the existing drainage were in existence. With the partial drainage (Group 1
pumps and D-3 underdrain) , our analyses indicate that the present stability would
be slightly greater than unity. This is verified by recent field observations. If
drainage is assumed to be fully effective, our studies have indicated that the
F.S. could be as great as 1.4. However, in our opinion, it probably will not be
possible to fully drain the gray, layered silts even with extra vertical drains.
Analyses have also been made to determine the effect of the
rock buttress as shown in Detail B, Fig. 7.2. Initially, it was assumed that
there was no drainage, but that the failure had to occur through the rock buttress.
Under these conditions the F.S. was slightly greater than unity. By combining the
partially effective drainage and the rock buttress, it was possible to compute an
approximate F.S. = 1.7. In this case we assumed that the drainage facilities
would relieve most of the uplift pressures, but that a sudden rain storm could fill
open cracks, producing uphill hydrostatic forces. If the rock buttress is positioned
as recommended, with the height varying with the location of the failure surface,
it is our opinion that this area should then have a reasonable degree of safety.
However, to assure the continued drawdown of artesian pressures, we recommend
that the horizontal drains be periodically inspected and cleaned out, particularly
if silting -in is indicated.
2. Remedial Section B
Remedial Section B extends northwestward from Sta. W-101+75 to
Sta. W-113+60. As shown in Fig. 7.2, this section has been divided into the
upper and lower slopes as separated by the W -Line.
100
a. Present conditions
Within this section all existing slopes appear to be stable,
however, the proposed A -Line cut has not been excavated. A 2:1 cut -slope
presently exists for about 400 feet along and above the W -Line north of Sta. W-101.
Geologic inspection has confirmed that the bedding in this area is locally dipping
into the hillside. However, the upper slopes are, in general, relatively flat.
The existing drainage is two -fold. An 18 -inch perforated
pipe underdrain is located parallel to the W -Line and is offset about 25 feet
uphill. It extends for the full length of Remedial Section B. Secondly, the
Group 2 deep -well pumps are located on a bench about 10 feet below the W -
Line grade, Figs. 6.2, 7.1 and 7.2. As previously stated, the pump production-,
rate for these pumps is generally quite small (less than 1,000 gallons per day)
except for those wells drilled deep enough to tap the underlying sands.
Our investigation of the subsurface conditions has revealed
that this section is one of the most complex in the project area. At varying depths
below the proposed A -Line roadway elevation there are deposits of artesian sands,
as discussed in Remedial Section A. The existing deep -wells within Group 2 are
intended to relieve much of this excess pressure. However, to further complicate
the situation, it was discovered that there are zones within the proposed A -Line
cut, where the laminated, gray silts dip toward the cut on angles as great as 20°.
In addition, much of the existing surface below the W -Line is covered with a
variable thickness of tan, clayey to sandy silt, which is similar in nature to the
material that comprises the bulk of the slide mass near Sta. L2-185.
Groundwater observations indicate that the water level is
presently about 10 feet above the elevation of the A -Line roadway west of
Sta. A-15; but is at or below the roadway elevation east of this station.
Piezometers located in the overlying gray massive and laminated silts are
somewhat erratic, because of perched water and discontinuous drainage.
TUKWILA INTERCHANGE
b. Recommendations
The A -Line cut will require re -sloping to a grade of 3:1, as
summarized in Fig. 7.2. From all indications, the predominant bedding planes
may lie essentially parallel to the recommended cut slope. Because of this,
potential failures in the cut slope should be relatively shallow and localized to
the extent that they would not endanger the W -Line upslope. As a result, we do
not foresee the need for a rock buttress above the A -Line in this section, as was
recommended above the W -Line wall in Section A.
A cylinder pile retaining wall will be required along those
areas where the recommended 3:1 slope does not reach the A -Line grade. This
wall will probably have a maximum exposed height of about 20 feet. Along most
of its length, the cylinders should develop their passive reistance from the gray
silts located below the A -Line roadway. The deflection and loading criteria for
this wall is the same as that for the W -Line wall, Remedial Section A (4 to 6
inches and E.F.P. = 60 p. c. f.) , except that .the passive resistance at the toe
will be developed in the silts. The coefficient of horizontal subgrade reaction
(kh) may be taken as a constant, equal to 200 pounds per cubic inch. The
maximum passive soil pressure (q0) may be increased with depth at the rate of
0.2 t. s. f. , from a value of 2.0 t. s. f. at the depth of the X -X line, Detail C,
Fig. 7.2.
Drainage in the lower slope should consist of horizontal
drains designed to tap the existing Group 2 wells as recommended in our
previous report and for Remedial Section A. Adequate drainage should be
provided to collect the flow from the horizontal drains. In addition, six
horizontal drains have been recommended for the upper slope. Four of these
are designed to drain the wet area above Sta. W-103, whereas the other two
will drain the tan silt found near the western end of Remedial Section B.
As shown in Fig. 7.1, the recommended upslope surface
ditch and subsurface intercepter drain terminates in Section B. This drainage
system, as shown in Detail A, Fig. 7.2, is designed to intercept all of the
upslope surface water, which is presently flowing into the various slide areas.
It is extremely important that the surface ditch be paved to prevent seepage
into the slopes. The perforated subsurface drain should be as deep as is
economically feasible, which may be on the order of 15 feet. The trench back-
fill should meet the standard State specifications for granular filter material.
As required, the cut slopes should be protected from erosion,
minor pop -outs, and "sapping" of sand layers through the use of an angular -
rock blanket. The details of rock specifications and blanket thickness should
be in conformance with State requirements.
c. Relative stability
Our revised analyses indicate that if the A -Line cut were
made without the benefit of subsurface drainage, the factor of safety might well
be slightly less than unity. After re -sloping to the presently planned grade of
2:1 and considering partial drainage, the factor of safety increases approximately
to 1.1, because of the steeply dipping beds. Fully effective drainage increases
the F.S. approximately to 1.4. By re -sloping to a grade of 3:1 and using a
cylinder pile wall, the stability may be increased to a value of about 1.6 without
effective drainage. By considering the drainage scheme to be at least partially
effective, the relative stability with the wall increases the F.S. to a value
greater than 2.
Except for the last one hundred feet at the western end of
Section B, the upper slope should be stable either because of the reverse dip
of the beds or the relatively flat slopes. However, the existing slope west of
and above Sta. W-113 is related to a failure, which is discussed subsequently
in Remedial Section C. Our study indicates that the factor of safety of the
existing upper slope is at or slightly below unity. However, by improving the
drainage and re -sloping to 4:1, the stability may be increased to a value ranging
from 1.4 to 2.3, depending on the drainage assumptions used in the calculations.
3. Remedial Section C
This section in many ways is very similar to Section B, though the
TUKWILA INTERCHANGE
101
required remedial measures are somewhat different. Remedial Section C is
shown in Fig. 7.3.
a. Present conditions
The lower slope is presently unexcavated and apparently
stable. However, the upper slope shows signs of movement on both sides of
the small drainage valley, which slopes down toward the W -Line near Sta. W-115.
These failures appear to have occurred along the contact between the overlying
tan, sandy to clayey silts and the underlying gray, clayey silt. These failures
are not too extensive at the present and have not damaged either the W -Line
grading or any upslope features.
The existing drainage facilities, as in Remedial Section B,
consist of the Group 2 pumps and the 18 -inch perforated underdrain along the
W -Line. During periods of heavy' rainfall,
ponding water was noted on the
W -Line and on the pump bench just below the W -Line. Even during dry periods,
water was observed to be standing on the pump bench.
b. Recommendations
The lower slope should be re -sloped to a grade of 3:1. Be-
cause of the geometry of the area, no retaining wall will be required at the toe
of this slope. However, the bedding structure is apparently not as steep (5°-10°)
in Remedial Section C, northwest of the A -Line wall. Therefore, the 3:1 recom-
mended cut should be buttressed with rock at the toe, to reduce the likelihood
of a slope failure. Because of the nature of the slope and dipping beds, such
failure would be more extensive than the local pop -outs, which may occur in
Remedial Section B.
A shear key will be required at the toe of the rock buttress,
as shown in Detail B, Fig. 7.3. This key in conjunction with the rock in front
of it should be designed to resist a shearing force of approximately 30 kips per
lineal foot. This shear key resistance should assure that the full strength of
the rock fill will be mobilized to resist a potential failure. It is presently
anticipated that the shear key will consist of 12 to 14 -inch structural steel
H -beams, set and concreted intore-bored holes spaced approximately P on
4 -foot centers. Generally, the key, will have about 5 feet of stick up and a
total vertical length somewhat grea `er than 15 feet.
The passive resistance of the key probably will be developed
in the gray SILTS. Because of the Confining effect of the rock in front of the key,
a maximum passive soil pressure (q1) equal to 5.0 t. s. f. , constant with depth,is
recommended. A coefficient of horizontal subsurface reaction (kh) equal to 200
pounds per cubic inch, constant with depth,is also recommended. As in Remedial
Section A, the rock should be placed in 1 to 2 -foot lifts and traffic -compacted,
if possible. For slope protection above the buttress and on the upper slope, a
thin (6 -inch to 1 -foot) •angular -rock blanket should be provided.
As in Section B, the lower slope drainage should consist of
horizontal drains to tap the vertical wells and some form of collection system to
carry off the flow.
The upper slope will require re -sloping to an approximate grade
of 4:1. In addition, this slope will require drainage both in the form of horizontal
drains and an upslope intercepter drain as shown in Detail A, Fig. 7.3. Observa-
tions indicate that these materials should drain quite well and that drainageshould
provide the required degree of stability.
As previously discussed in Part 6, there is a local wet zone
under the W -Line in the vicinity of Sta. W-116. If tests by the State reveal that
this water is not coming from a leak in the pump -collector drain, some form of
special drainage may have to be provided. These measures could consist of either
short horizontal drains drilled from the existing Group 2 pump -bench or some system
of vertical, upslope drainage, which could in turn be drained by horizontal drains.
c. Relative stability
As presently designed and/or constructed, both the upper and
lower slopes would have a factor of safety at or slightly below unity if no drainage
were assumed. Through re -sloping and drainage it appears that the upper slope
TUKWILA INTERCHANGE
10
stability could be increased to a value approaching 1.5, which should be
acceptable.
In the lower slope from the W -Line down to the Ls -Line,
drainage has less effect on the stability as indicated by an increase in factor
of safety from 0.9 to about 1.2. This is improved to about 1.5 with the addition
of the rock buttress as recommended above.
4. Remedial Section D
-377
This section includes the "Point" (below the cul-de-sac) and the
small slide area, adjacent to the south end of the 51st Ave. bridge structure, and
immediately behind the existing Ls -Line cylinder pile wall. In general, the soil
conditions are similar to those in Remedial Section C, although some of the
remedial measures are different. Remedial Section D is shown in Fig. 7.3.
a. Present conditions
At some time prior to December, 1965, a small slide (about
100 feet wide) developed down-slope from the W -Line and progressed uphill until
it was encroaching on the W -Line. At this time (December, 1965), it was noted
that the existing cylinder pile wall had deflected outward by approximately 3/4 -
inch. The slide left a 3 to 4 -foot scarp and numerous cracks in the W -Line road-
way. Although steeply dipping beds (20° - 26°) were observed at the toe of the
slide and periods of heavy rainfall were experienced, apparently no significant
movement has occurred since the initial sliding. Also, the cylinder pile wall
shows no signs of distress.
The upper slopes, referred to as the "Point" , are presently cut
on a slope of 2:1. As previously stated, Slope Indicator observations indicated
that this area was beginning to creep at an alarming rate during the months of
November and December, 1965. The location of the failure surface was later
confirmedby several inclinometer observations. The installation of six to eight
horizontal test drains in late December confirmed the opinion that the fissured
silts might be drained. Continued Slope Indicator observations have shown that
the rate of movement declined rather suddenly after the horizontal test drains
were installed, even though the rainfall rate continued at a relatively high level.
Most of the existing surface drainage is through natural
means, although the D-1 drain presently collects some of the surface water
from the area of the cul-de-sac. In addition, a few of the western -most
wells of the Group 2 pumps are located within this section. At least one of
these has been removed because of the slide previously discussed.
b. Recommendations
In the slide area behind the cylinder pile wall, much of the
debris should be excavated and replaced with either a rock buttress, or compacted
granular fill which will provide the required support for the W -Line. No shear
key will be required for that portion of the buttress which is located behind the
existing wall; however, the shear key recommended for Remedial Section C
should be extended into Section D as far as the eastern end of the existing wall.
Also, as in Sections A, B and C, horizontal drains should be installed to tap all
of the vertical wells.
The upper slope will require re -sloping to conform with the
recommended slopes adjacent to them. Re -sloping will also have the tendency of
localizing any potential failures and limiting such failures -to relatively small
pop -outs. As suggested for other cut slopes, a thin, angular -rock blanket may
be used to provide slope protection. In addition, drainage should be improved
by the installation of a few more horizontal 'drains from the W -Line elevation
•
and the construction of the upslope intercepter drains as shown in Detail A,
Fig. 7.3.
c. Relative stability
As indicated by the existing slide debris and scarp (and
verified by our simplified stability analyses) , the existing lower slope had a
factor of safety well below unity. It has been determined, because of the
adverse dip of the soil beds, that an improvement of the drainage alone would
only increase the stability to slightly over Unity. However, the addition of a
rock buttress should boost the factor of safety to a value equal to or greater than
2.0, which should be adequate to provide protection to the W -Line and the
bridge abutment.
TUKWILA INTERCHANGE
103
Based on Slope Indicator observations and stability analyses,
the factor of safety of the upper slope (Point) has improved from a value some-
what less than unity to a value somewhat greater than unity as a result of limited
horizontal drainage. In our opinion, this would be improved to a value somewhere
between 1.5 and 2.0, when the recommended drainage and re -sloping is completed.
5. Remedial Section E
In general, the remedial sections west of the cul-de-sac require
remedial measures, which are somewhat less complex than those to the east.
Remedial Section E is shown in Fig. 7.4.
a. Present conditions
Remedial Section E represents an area composed of massive gray
silt overlying laminated silts presently sloped at 2.5:1 to 3:1. The eastern half
of Section E is apparently stable as a result of the test drainage around the Point.
However, since observations began in December, 1965, the slide located in the
western half of the section has progressed upslope and expanded somewhat,
laterally. Field observations have led us to believe that this slide has developed
along the weaker clay laminae, which tend to dip toward the 0 -Line on an average
slope of about 10°. Visual inspection of natural test pits confirmed in several
locations that there were broad, wet, slickensided surfaces on which sliding was
occurring. As sliding has progressed, the depth of failure has become deeper
because the inclination of the failure surface is less than that of the cut slope.
During the past two months, a sizeable bulge has developed at the toe where
unstable material is tending to over -ride stable material. Thus far, the slide
has not severely encroached upon the 0 -Line.
Some of the upslope drainage is carried down to the L2 -Line
via an existing culvert. However, some of the surface runoff flows into unpaved
upslope ditches which lie parallel to the top of the slope. Much of this flow then
seeps into the hillside at points where it is most detrimental.
b. Recommendations
Drainage in the form of horizontal drains and an upslope
intercepter drain should be installed as the first remedial measure. The cut
slopes indicated above the 0 -Line should then be re -sloped to a grade of 4:1.
These items, along with an erosion control blanket, should comprise all that is
required for the eastern half of Remedial Section E.
Because of the adverse structure control of the existing slide
uphill from the 0 -Line (between Sta. 0-187 and 0-190) a 15 -foot high rock
buttress has been recommended. This buttress should add a significant amount
of shearing resistance to the toe of the slope and greatly limit the possibility of
future slide activity within Section E. In order to assure full effectiveness of the
buttress, a shear key, similar to that recommended in Remedial Section C, .should
be provided. The combined shear resistance of the toe of the rock and the key
should be approximately 35 kips per lineal foot. As discussed subsequently,
this buttress and key should extend westward to Sta. L2-182+40 in Remedial
Section F, Figs. 7.1 and 7.4.
c. Relative stability
Our computations indicate that the recommended drainage and
re -sloping would improve the stability from a condition of active sliding to a
factor of safety greater than 1.2. In our opinion, no drainage facilities will
be 100 percent effective. Therefore, a buttress has been recommended to
provide the extra protection required in the event that drainage becomes in-
effective. Depending upon the assumed degree of drainage, a buttress may
provide a factor of safety ranging from about 1.3 to 2.5.
6. Remedial Section F
a. Present conditions
Remedial Section F (Fig. 7.1) is a highly unstable area,
where a fairly thick layer of tan, saturated, sandy to clayey silt overlies the
gray, laminated silts. The eastern half of the section is all part of one large
TUKWILA INTERCHANGE
104
block -flow type slide, which is coalescing with two smaller slides, extending
to the western extremity of Section F. As indicated by the slide movement
stakes, the movement is continuing at a fairly constant rate. Near the toe of
the slide, the saturated mass has disintegrated into a mudflow. In some areas
of the big slide, the mud debris has flowed out toform slopes which have an
average grade as flat as 5:1. At the head of this slide there is a near vertical,
20 -foot scarp.
All of the upslope surface drainage from this section (and
also from further west) is presently funneling into the three slide areas in
Section F . However, recently installed horizontal test drains indicate that both
the saturated slide mass and the underlying gray silts may at least be partially
drained.
b. Recommendations
In general, the recommended remedial measures for this
section (shown in Figs. 7.1 and 7.4) are the same as those for Section E, with
the exception of horizontal drain spacing. However, of prime importance is the
construction of the upslope intercepter drain as shown in Figs. 7.4. This alone
would greatly improve the present situation. Because of the magnitude of the slide
mass`in the eastern half of Section F, and in order to assure adequate support at
the toe of the softened slope, a rock buttress has been suggested to provide
additional stability in the event that the planned drainage scheme is not fully
effective.
In some areas, re -grading to a 4:1 slope may require the
placement of fill. This condition will probably occur at the head of the large
slide mass opposite Sta. L2-185, in which a vertical scarp on the order of 20
feet high presently exists. Further, the slide mass is remolded and fully saturated
from surface drainage upslope. A horizontal test drain recently installed in the
toe of the slide has been regularly flowing, and indicates that the mass may be
satisfactorily drained. The effect of drainage upon the strength properties of
the slide mass has not been determined. If after drainage and re -sloping, soft
materials still persist in the slope underneath the slide debris, such zones
should be removed and backfilled with freely -draining granular materials,
compacted under controlled conditions. Support'for the scarp at the head of
the slide should also be provided by similar methods, in order to obtain a
slope of adequate strength. Unless conditions are very dry, use of the
remolded slide material for backfill in the slope is not recommended because
of the high percentage of fines.
c. Relative stability
Stability analyses indicate that drainage should effectively
stabilize the slides in this section. In spite of the relatively large indicated
factor of safety for fully effective drainage, the!use of a rock buttress is, in
our opinion, necessary because of the magnitude of the slide and yet undetermined
effect of drainage on the strength of the remolded slide materials. Based on our
stability calculations, a buttress should provide a narrow margin of safety even
if the drainage provisions completely fail.
7. Remedial Sections G and H
a. Present conditions
The two western -most Remedial Sections (G and H) are
essentially stable at the present time. These sections are shown in Figs. 7.1
and 7.5. Because of wet conditions in Section H, it has not been graded to its
original design slope. On the other hand, Section G is presently graded to a
slope of 3:1, which steepens to 2.5:1 near the top.
Geologically, both sections are quite similar. Boring data
indicate that there is a deposit, 50 feet in thickness, of brown, saturated,
fine to medium sand located upslope from the present right-of-way line. This
deposit appears to extend at least 1,000 feet upslope to the south, where there
is a commercial sand pit in operation. The water in .this sand appears to be
trapped behind a natural dam composed of a glacial till deposit and an underlying
gray, clayey silt. Piezometers in this area have shown that artesian pressures
TUKWILA INTERCHANGE
105
existed behind the dam. Another observation, which is pertinent to the present
stability, is that this area probably is located outside of the limits of the
ancient slide, Fig. 5.1.
Once the water conditions in this area became known,
horizontal test drains were installed. These were drilled from the L2 -Line
elevation upward and into the slope on a grade of about 8 percent. Several
of these drains were observed to be flowing at or near the full -pipe rate,
which was measured at 95 to 100 gallons per minute. In general, the water
was quite clean, although one drain flowed "dirty" for several weeks. As a
result, a small (6 -foot diameter and 3 -foot deep) sink -hole developed upslope,
approximately 20 feet west of inclinometer N9, Fig. 3.1. Special observations
were made to determine the effect of drainage on the groundwater level. As
shown in Fig. 6.17, the observed water levels dropped significantly as a direct
result of the drain installation. The swampy area in the vicinity of inclinometer
N9 was observed to be nearly dry within a week after drain installation.
b. Recommendations
Because of the apparent stability of Sections G and H, the
amount of recommended remedial work is quite minimal. In our opinion, these
measures are desirable to assure a continued stable condition.
We have recommended that the cut slopes be re -graded to
3.5:1. This, along with the recommended horizontal drainage, should effectively
increase the present stability of these slopes. Drainage of the sand "reservoirs"
upslope may also tend to improve the groundwater conditions in some of the
remedial sections to the east. As recommended for Remedial Sections B, C, D,
E and F, the upslope intercepter drain should be constructed across Sections G
and H as shown in Figs. 7.1 and 7.5. The cut slopes should also be protected
with a rock blanket as recommended in the other remedial sections.
c. Relative stability
As previously indicated, the slopes in Sections G and H are
presently stable despite the adverse water conditions. Stability studies indicated
that the recommended re -sloping and drainage should provide a factor of safety
in excess of 2.0.
A general summary of slope stability is given in Fig. 7.6. It is empha-
sized that these results are presented only as a means for comparing the relative
effects of the various remedial measures on the stability of the slopes. Because
of the variation between the assumed subsurface ,conditions and those actually
exisitng, in addition to the limitations of the analytical methods of analyses, it
is inappropriate to attach any particular significance to the actual values of the
factors of safety given herein.
TUKWILA INTERCHANGE
106
yllnder pHs wall
•
• • --..
- -
•
0
LEGEND
Horizontol Drains
Existing test drains
Recommended drain (Grade' 8-l0%)
Recommended drain (Grade: 1-3 %)
Other Features
Cylinder pile wall
Cir:"g9 Rock buttress
Proposed Intercepter drain 8 ditch
Existing or proposed Right of Way
Additional vertical drains (6 to 9 in. dia.)
100
107
200
300
400
500
SCALE: FEET
TUKWILA INTERCHANGE
AGREEMENT Y -7I3, SUPPLEMENT 6
PLAN OF RECOMMENDED •
REMEDIAL MEASURES
March 31,1966 W-64-46813
SHANNON & WILSON
SOIL MECHAM<
Toe of rock buttress
Proposed Right of Way
Approx. location of
Intercepter Drain
Existing D-3 drain
Existing poved ditch
Group 1 Pumps
Paved ditch
e
Clayey SILT
.
Horizontal Drain GI
Rock Buttress (Detail B)
W Line
A - I
Dense SAND
Droin
Surface seal I A
(12'mia) SILT ILS
REMEDIAL SECTION A
(NOT TO SCALE)
Filter man.
Perforated
drain pipe
DETAIL A
INTERCEPTER DRAIN
Upper Slope
Detail A Existing underdrain
rPresent ground surface
Horizontal Drain gz
F
Present ground surface
tae
Proposed Cylinder Pile Wall
(See Detail C for lateral loadings)
Cylinder Pile Wall
W Line
Cylinder
Pile Wall
DETAIL B
ROCK BUTTRESS
Group 2 Pumps
Lower Slope
Present ground surface
SODA SILT ��pp ----- _
`let DAS _
toga I cu
LOminoted SIL ``"'"'.
Horizontol DrainG`_
Length F
Gray SILT
REMEDIAL SECTION B
(NOT TO SCALE)
DETAIL C
CYLINDER PILE LOAD DIAGRAM
Proposed Cylinder Pile Wall
(See Detail C for lateral loadings)
MAX. PASSIVE PRESSURES
(See Note 3)
kh
Q.
X 0 200 O=.0i .f.x
SILT • 2 kalif t.
(Sect.8)
0 0 1.0t.s.f. X
SAND X ..._ 0.2 t s.f./ft.
(Sect. A)
60 lbs./in?/ft.
REMEDIAL
SECTION
A
B
(Upper
Slope)
STATIONS
L's 2529+00
to
W 95+50
W 95+50
to
W 99+00
W 99+00
to
W I00+00
PRESENT
SLOPE
RE -SLOPE
(A)
SUMMARY OF REMEDIAL MEASURES
REMEDIAL MEASURES
RETAINING WALL
HEIGHT
181
E.F.P.
go
kh
ROCK
BUTTRESS
Varies
Varies
Varies
Sae Note 2
3:1
None
60 p.c.t
Detail C
See Note 3
SLOPES
(4)
(K)
(L)
None
J•1.511
K• 6:1
L• 2:1
ROCK
BLANKET
THICKNESS
(D)
INTERCEPTER
DRAIN
MIN.
DEPTH
(E)
HORIZONTAL DRAINS
TIP
OFFSET
(F)
See Note 1
See Note 1
None
Existing
D-3
. Drain
Only
See Note 4
220'to 240'
NO.
8
SPACI NG
GRADE
(8,)
15 Each
See Note
N0.
e
SPACING
GRADE
(Gs)
None
REMARKS
3:1
to
4:1
60 p.c.f.
Detail C
See Note 3
J • 1.5:1
K• 6:1
L•2:1
See Note I
Existing
D-3
Drain
Only
150o180'
6 Each
See NoteS
None
W 100+00
to
W 10I• 00
Varies
4:1
-25'
60 p.c.f.
Detail C
See Note 3
J•1.5:1
K. 6:1
L•2:1
None
W 101+ 00
to
W 101+75
W 101+75
to
W 106+00
Varies
2:1
See Note 2
None
None
None
None
None
See Note!
See Note!
Existing
D-3
Drain
Only
None
None
'-130'
3 Eoah
1%
See NoteS
None
None
250'
None
40I00'
7 to I0%
W 106+00
to
W 112+00
W 112 +00
to
W 113+60
B A 20440
(Lwer to
Slope) A 18+70
A 18+70
to
Ls 197+55
Varies
None
None
None
None
1 None
None
None
None
2:I
Varies
4:1
3:1
None
None
None
None
See Note 1
See Note!
15'
None
150'
None
-150' Approx.
See Note 5 6F25'
I%
2050'
8 to10%
None
Varies
3:1 -22' Max. 60 p.c.f. None
Detail C
See Note 3
See Note 1
None
150'10200' 43925' None
See NoteS I%
NOTES:
1. As required for erosion control.
2. Re - slope as presently designed.
3. Maximum passive resistance (q0), tons per sg.tt.,
Increases with depth below the X -X line.
The coefficient of horizontal subgrode reaction
(kh), lbs. per cubic Inch, varies as shown. See Detail C.
4. No additional drains required.
5. Drains should be spaced 8 drilled to intercept verticol wells.
Drain pipe may be perforated for the entire length, except
for 10 ft. of the discharge end, which should be unperforated
8 sealed around the outside.
TUKWILA INTERCHANGE
AGREEMENT Y- 713, SUPPLEMENT 6
REMEDIAL MEASURES
SECTIONS A & B
MARCH 31,1966 W-64-4688
SHANNON & WILSON
SOIL. MECHANICS & FOUNDATION ENGINEERS
108
PART 8 Conclusions
Detail A
Paved ditch
Surface seal (12•)
Rock Blanket
Gra
4 cfo
(Di)4A SILT
— —
110
Rock Buttress
_Present ground surface
C
1
0 0Horizontal Drain
Grade GI
F
W
(Detail e)
ape
�a1�o
Ls Line
Paved Ditch
Filter material
Perforated drain pipe
DETAIL A
Detail A
Ta nSILT
r
REMEDIAL SECTION E
(NOT TO SCALE)
D_ ______ _Present ground surface
Rock o.
n6et
FBrown, silty SAND
H ri
°ttl Drooin
Gray- brown, sandy SILT
r a
Horizontal Drain
Cuts
Gray, clayey SILT
Pe
Rock Buttress
0.45°
Rock buttress
3 .150 p.cf.
Grade G=
Grade GI
R • shear on key
(Kips per lin. fopt )
Detail B
Shear key
DETAIL B
Paved Ditch
Ls Line
F
REMEDIAL SECTION F
(NOT TO SCALE)
SILT
0 • 25°(across dip)
C = 0
r =125 p.c.f.
q°bnax) 5.0t.s.f.
See Note 3
kh •200Ibs/cu.In.
(constant)
SUMMARY OF REMEDIAL MEASURES
REMEDIAL
SECTION
STATIONS
PRESENT
SLOPE
REMEDIAL MEASURES
REMARKS
RE -SLOPE
(A)
ROCK BUTTRESS
SHEAR KEY
KIPS PER
LIN.
IR) '
ROCK
BLANKET
THICKNESS
ID)
INTERCEPTER
DRAIN
MIN.
DEPTH
(E)
HORIZONTAL DRAINS
HEIGHT
(B)
SLOPE
(C)
OFFSET TIP
IF)
8
SPACING
GRADE
(51)
8
SPACING
GRADE
(Gsl
E
L2 192+00
to
Ls 189+90
2:1
4:1
None
None
None
See Note 2
15'
'-550'
30100'
Ito 3%
None
See Note I
Lz 189+80
to
Lz 186 + 30
2.5:1
4:I
—15'
6:1
35 K/lin.ft
See Note 2
15'
—550'
7050'
Ito 39L
None
F
Ls 186 + 30
to
Ls 182+40
—3:1
4:1
15'
6:1
35 K/Iin.ft
See Note 2
15'
—450'
—400'
7050'
Ito 3%
8050'
8to107°
Ls 182 + 40
to
Ls 176 + 20
3:1
4:1
None
None
None
See Note 2
15'
"300'
40100'
Ito3%
11050'
101°
NOTES:
I. Space drains between existing drains.
2. As required for erosion control.
3. q° is mox. passive resistance, tons par square foot.
kh is coef. of horizontal subgrade reaction, lbs. per cubic inch.
TUKWILA INTERCHANGE
AGREEMENT Y-713, SUPPLEMENT 6
REMEDIAL MEASURES
SECTIONS E 81 F
MARCH 31,1966 W-64-4688
SHANNON & WILSON
5011. MECHANICS 8 FOUNDATION ENGINEERS
SAND
Detail A
Upper Slope
W Line
Present ground surface
ket
Grote=1
61 -`—
C/aye`
F
Exist underdroin
Paved ditch
Surface seal (12•)
Filter material
Perforated drain pipe
DETAIL A
Upper Slope
Lower Slope
(Ls Line Cut)
Existing Group 2 pumps
•
Present ground surface
�ck 8jon
ker S
Horizontal Drain GI
REMEDIAL SECTION C
(NOT TO SCALE)
Ls Line
buttress I
------
Detail8
R
Shear key
Rock buttress
0.45°
IS • 150p.c.f.
Paved ditch
Shear key
DETAIL B
D
Cul - de -sac
r Presentground surface
mak. 878nker /I__
-- �\� W Line
Exist. underdroin
Horizontal Drain G,
Croy, ete
YeY SILT\`
F
Lower Slope
(L° Line Cut)
Excovate slide debris
Present ground surface
Rock Buttress
L°Line
Detail
Toe of existing cylinder pile wall
Horizontal Drain 6,
Sheer key
F
REMEDIAL SECTION D
(NOT TO SCALE)
SILT
0 •25° (across dip)
C•0
• 125 p.c.f.
q,(max) • 5.0 t.s.f.
See Note 6
kb •200 I bs/cu. In. (constant)
i
109
REMEDIAL
SECTION
(UPPER
SLOPE)
(Ls LINE
CUT)
D
(UPPER
SLOPE)
D
(LOWER
SLOPE)
STATIONS
W 113+60
to
W 117+30
PRESENT
SLOPE
2:1
RE -SLOPE
(A)
4:1
SUMMARY OF REMEDIAL MEASURES
REMEDIAL MEASURES
RETAINING SHEAR ROCK ROCK
WALL KEY BUTTRESS BLANKET
HEIGHT
(8)
None
LENGTH (L)
SHEAR (R)
THICKNESS
(C)
SLOPE (S)
None
THICKNESS
(0)
See Note!
INTERCEPTER
DRAIN
MIN
DEPTH
(E)
HORIZONTAL DRAINS
TIP
OFFSET
(E)
NO.
8
SPACING
GRADE
(G,)
NO
8
SPACING
GRADE.
(Gz)
REMARKS
15'
200'
300'
20100'
1 to3%
8050'
8 to10%
Le 197+55
to
Ls 194 +00
None
3:1
Nae
L=35511.
R r30nft
C > 10'
S•611
See Note!
None
See Note 2
15025'
1%
W 117+30
to
0 192+20
2:1
4:1
None
Ls 194+00
to
Le I92+00
—2:1
See Note 4
No additional
walls req.
L= 60'
R•30K/lin.
ft.
See Note 3
None
_(0'
See Note 4
See Note
See NI to 1
15'
200' to
300'
2 @I00
I to3%
None
See Note 5
See Note 5
NOTES:
I. As required for erosion control.
2. Drill long enough to intercept existing deep wells
3. Sheer key should extend eastward from existing wall.
4. Excavate slide debris and bockfill with rock
buttress sloped so os to support W- Line and fit
behind existing cylinder pile well. - t
5. As required to drain oli existing deep wells.
6. qe is max.possive resistance, tons per squore foot.
kh is coat of horizontal subgrade reaction, Ibs. per cubic Inch.
TUKWILA INTERCHANGE
AGREEMENT Y-713, SUPPLEMENT 6
REMEDIAL MEASURES
SECTIONS C a D
MARCH 31, 1966 W-64-4688
SHANNON & WILSON
SOIL MECHANICS & FOUNDATION ENGINEERS
. silt`ND
Detail A
Groy - brown SANG
Massive SILT
Detail A
o
Present ground surface
Cur S 0
tinker
o rzon=al Drain G2
— _ TILL /
Horizontal Droin GI
p
r -Paved Ditch
L= Line
Laminated SILT = --12•
Paved ditch
Surface seal (l2")
Filter material
Perforated drain pipe
DETAIL A
D
Rock Blanket
REMEDIAL SECTION G
( NOT TO SCALE )
Gray -brown SAND
—tiSri�ontal Drain Gz
Gray SILT
ut
IDPe
Present ground surface
Paved Ditch
L= Line
TILL
F
REMEDIAL SECTION H
(NOT TO SCALE)
SUMMARY OF REMEDIAL MEASURES
REMEDIAL
SECTION
STATIONS
REMEDIAL MEASURES
REMARKS
PRESENT
SLOPE
ROCK BUTTRESS
SHEAR KEY
KIPS PER
LIN.FT.
(R)
ROCK
BLANKET
THICKNESS
(D)
INTERCEPTER
HORIZONTAL DRAINS
RE -SLOPE
(A)
HEIGHT
(81
SLOPE
(C)
DRAIN
MIN.
DEPTH
(E)
TIP
OFFSET
(F)
NO.
- 6
G AIDE
(GI)
NO.
8
GRA EO
(G:)
G
L5 176+20
to
Lx 171+00
3:1
3.5:1
None
None
None
See Note 3,
15'
360'
280'
5 @100'
1 to3%
None
None
4@I00'
8 to 10%
See Note I
H
Lt 171+00
to
Ls 169+ 00
Varies
3.5:1
None
None
None
SeeNote3
15'
410'
420'
330'
None
None
None
(Only
8to10Y.
'Only
8to107.
lOnly
8to10%
Station
Lt 170+95
L5169+45
Lit 169+25
i
NOTES:
I. Space drains n 50'o4 and alternate between GI and G=
2. Remedial Section H requires only 3drains in addition to
those in the existing test section.
3. As required for erosion control
TUKWILA INTERCHANGE
AGREEMENT Y - 713, SUPPLEMENT 6
REMEDIAL MEASURES
SECTIONS G & H
MARCH 31, 1966 W -64-468B
SHANNON & WILSON
SOIL MECHANICS & FOUNDATION ENGINEERS
FIG. 7.5
Soil Properties
I. Clayey SILT: = 14° ' (along dip)
= 25° (across dip)
C = 0
X = 125 p.c.f. (moist)
2. Rock FILL:
QS = 45°
C = 0
6 = 150 p.c.f.
Typical Method of Analysis
Ph=Y225H2K
Tension crack
W
IIIIIIIIIIImmummi,,...
Dip of failure plane (a)
F.S. _ (Normal Forces) tan 0 [W(cos o<)-u]ton 0
Driving Forces Ph+ W(sina)
GENERAL SUMMARY OF SLOPE STABILITY
Remedial
Section
(See Fig.7.I)
Remarks
APPROXIMATE FACTOR OF SAFETY
AFTER VARIOUS REMEDIAL MEASURES (See Note I)
Present
design
condition
w/o drains
With
partia I
drainage
only
With fully
effective
drainage
only
With
rock
buttress
only
With
drains
a rock
buttress '
With
cylinder
pile wall
only
With
drains a
cylinder
pile wall
A
0.6 to0.8
1.1
1.4
1.1
See Note 2
1.7
See Note 2
-
. See Note 3
-
See Note 3
B
Upper
Slope
0.8
See Note 4
1.4
2.3
-
-
-
-
A-Line1.6
Cut
0.9
I. 1
1.4
_
_
See Note 5
2.4
See Note 5
C
Upper
Slope
0.9
1.3
I.5
-
-
-
-
Ls -Line
Cut
0.9
I. 1
1.2
I. 4
1:5
-
-
D
The "Point"
<1.0
I.5
2.0
-
-
-
-
Lower Cut
0.6
0.8
1.0
1.9
2.4
-
-
E
0.5to0.8
1.2
1.4
1.3
2.5
-
-
F
0.8 to 1.0
2.0
3.6
1.05
4.6
-
-
G
>1.0
1.5 to 2.6
6.5
-
-
-
-
H
>1.0
2.7
>10.0
-
-
-
-
NOTES:
I. All conditions shown below assume that recommended re -sloping
has been completed.
2. In vicinity of Sta. W I00+50 (4:1 cut slope).
3. Assumes potential failure surface passes above top -of -wall elevation.
4. In vicinity of Sta. WI 13+00.
5. Assumes that failure cannot occur through or under wall.
TUKWILA INTERCHANGE
AGREEMENT Y -7I3 SUPPLEMENT 6
SUMMARY OF SLOPE STABILITY
MARCH 31, 1966 W -64-468B
SHANNON & WILSON
SOIL MECHANICS & FOUNDATION ENGINEERS
Appendix B
Discussion of Slope Stability Analyses
August 9, 1995
Supplemental Slope Stability Data
Rodger Lacy Residence
51st Avenue South
Tukwila, Washington
The Galli Group Inc.
13500 Lake City Way NE, Suite 202
Seattle, Washington 98125
206-363-6449
Discussion of Slope Stability Analyses
The following data is intended to supplement our report, Geotechnical Investigation for
Rodger E. Lacy Sr., 51st Avenue South, Tukwila, Washington, dated March 15, 1995. In
particular we have attempted to provide representative analyses of the lower slope below
the Lacy residence under two conditions:
1. Pseudostatic analyses for slope stability under seismic conditions
2. Static analyses for slope stability under current conditions
Selection of Representative Profile
The analyses attempt to model the slope conditions since construction of the Tukwila
Interchange in the mid -1960's, and include assumptions and parameters based upon
subsurface information provided in Slope Stability Investigation, Tukwila Interchange, for
the Washington State Highway Commission, April 30, 1966, performed by Shannon and
Wilson, Inc. The profile selected for our representative analysis is shown in Figure B-1,
and corresponds to profile 13, Figure 5.1 of the Shannon and Wilson report. The profile
begins where SR 518 passes underneath the 51st Avenue South bridge and ascends
upslope through the approximate location of the proposed Lacy residence. The profile as
shown in Figure B-1 shows the regrading at 4H:1 V (Horizontal: Vertical) accomplished
during construction of the interchange. We concluded this regraded profile adequately
represents the slope conditions below the Lacy property.
Selection of Soil Parameters
Soil parameters used in the analyses were derived from the Shannon and Wilson
laboratory and field testing described in the above report (see Appendix A, and
Bibliography to Galli Group Report). Field testing and subsurface investigation led
Shannon and Wilson to settle on soil parameters reflective of the inclination of clay
laminations within the massive silts comprising the lower slopes as opposed to laboratory
parameters. For example, on the slopes west and north of the Lacy property, actual slope
failures indicated an inclination of the failure plane at approximately 14 degrees. (Other
borings logged the orientation and inclination of the clayey silt laminae). Field testing
indicated values of approximately 20 to 27 degrees, while laboratory testing indicated
friction angles of 30 to 31 degrees. By back calculating in areas of observed failure, they
concluded the internal friction angle roughly approaches the inclination angle of the clay
laminae on the lower slopes.
The slope below the Lacy property appears to have no consistent orientation to the clay
laminae; it is described by Shannon and Wilson as a zone where previous folding may have
occurred. The effect of these zones of "cross bedding" would be to increase the internal
friction angle. This appears supported by the fact that the steepness of the slope below the
Lacy property prior to remediation varied from 2.4H:1 V to 2H:1 V, and the slope seemed
stable. Based upon this information, the results of the Shannon and Wilson subsurface
exploration, available laboratory and field testing, and review of the available information
on the area, we selected what we believe to be reasonably conservative soil parameters
described below and shown on the attached Figure B-2.
B-1
Soil Region Soil Conditions
Internal Friction Angle, 0 Cohesion, C
1 (lower slope) Anisotropic, clayey SILT 17° within 20° of laminae orientation 0
21° from 20° to 40° of laminae orientation 0
25° from 40° to 90° of laminae orientation 0
2 (0'-15' depth) Silty Sand
30° 0
(15'-30' depth) Massive SILT, cross bedding 25° 0
Method of Analysis
We tried to model a "worst case" scenario for the lower slope. Using the above
conservative estimates of soil parameters, we modeled the slope below the Lacy residence
under a design seismic event of magnitude 6.5, estimated to cause a lateral ground
acceleration of 0.17g. Based upon field observations of slope failures prior to and during
excavation associated with construction of the Tukwila Interchange, it appears the mode
of failure for the slope, should it occur, would likely be progressive shallow failures of the
slope beginning at the lower reaches near the 0 -line, which migrate upslope over time if
left unremediated. We utilized PCSTABL5, a slope stability program developed by
Purdue University to analyze the slope below the Lacy residence. The following
assumptions were incorporated into our analyses.
• Soil parameters described above
• Lateral ground acceleration of 0.17g
• Sliding Block analysis for lower slope (oriented with clay laminations)
• Random Analysis of critical failure plane for upper slopes
• After a failure occurs, we assumed reconfigured slope with head scarp
equivalent to 1/3 of the depth of the failure (see Figure B-2)
• We conducted repeated analyses upslope after successive failures
The actual data from the computer analyses can be found in Appendix C.
Observations and Conclusions
• Under static conditions, the lower slope below the Lacy Residence is estimated to
have a factor of safety of approximately 1.8 (1.5 is considered adequate)
• Under seismic analyses, portions of the lower slope show factors of safety less than
unity (indicating potential slope movement)
• As repeated failures progress upslope, the factor of safety approaches 1.3 (for failure
with headscarp within 120 feet of the Lacy Residence) and 1.6 for a slope failure
influencing the Lacy residence. (1.2 is considered adequate for seismic analysis)
• Under repeated progressive slope failures, our analyses indicates the slide mass
diminishes in size and depth as failures move progressively up slope toward the Lacy
residence
B-2
• It is very unlikely that the duration of one seismic event would cause all of these
progressive failures to occur
• Increase in ground water levels is not likely to affect the relatively shallow failures of
the upper slope
Summary
Utilizing conservative assumptions for soil parameters (equivalent to 60% of the
laboratory test values, and neglecting apparent cohesion), incorporating conservative
assumptions regarding the progressive failure of the slope, and based upon our
investigation of the Lacy property and review of the Shannon and Wilson data for the
lower slopes, our analysis indicates that the lower slopes appear stable under current
conditions. Under seismic analysis, the lower slopes may experience some shallow slope
failures, which may migrate upslope over time if not remediated. However, it appears the
failures would not encroach upon the Lacy property or affect the Lacy residence.
It should be noted that this represents a conservative assessment of the soil conditions of
the lower slope. Under static conditions, utilizing the same assumptions, our analysis
indicates a factor of safety of less than unity for isolated portions of the lower slope.
Since the slope currently appears stable, this would indicate that our assumptions are
reasonably conservative regarding the soil conditions. Our analysis did not include the
beneficial effects of any rock buttresses or horizontal drains which have been placed at the
toe of the lower slope.
This analysis is intended to provide prudent assessment of the stability of the slope and its
impacts on the Lacy property. It is not intended to provide a detailed assessment of the
stability of the lower slope within the WSDOT right of way. Typically, when slopes are
cut for a WSDOT project, they are designed to provide a minimum factor of safety of 1.5
for slopes impacting structures and 1.2 for other cut slopes.
B-3
(44140; ?_23)
Zo 7)
a
206
C - 11G.4 - 30
(2s,l9si
S-16 205 I
2W
Slide zone
13
Layered zone
(D(pN 12° west)
7
Sl(cke'ns(de=
Hard, gray, clayey SILT
es -
N4
Possible shear zone
OLine
(20,136)
202
1
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
Gray, silty CLAY
Gray, fine SAND
Hard, gray, clayey SILT
Horizontal drain
7
10°
Piezometer dry
X=0
PROFILE 13 0191+88
L2 Line
DLine
250
200
150
100
50
CROSS : SC07" LON13-
LACE i• NOi.1E•
FA/Cu R£ 8
FRN_M1% IL
':
18o
O EINE
FA) I:uRE . I
PROs ECT NSW Su RF ACE PRpf•ILE.-'
ASSU m ED" WATER SU CFA CZ — I,LO
': FAILURE SuRFAt.E FAG -mit G: sAFE-r' - h ,j*op.�.
0.71 8LOOK
0. SZ RANC.OM.
HOk1E.1JT
y O t30 Rom . '
....:Rom
7:.•
'8 7. 3 4 PDm
-a Pi- (Err ENDED To 4o.5, -I.. (2
1.12.0 Erg AM : Sou.. PARAMETFR.S• SEis. LoEFrICFIJT.
ANI$o17 oPtC. O.'1"7.
ANISOTTG0PIC
THE GAW GROUP
UIGINEERS & CONSULTANTS
-13500 LAKE CITY WAY NE. SUITE 202
SEATTLE,WA 98125
SCRIE APPROVED RT:. DRAWN E}
REn1ED
Appendix C
Supporting Data for Stability Analysis
August 9, 1995
Supplemental Slope Stability Data
Rodger Lacy Residence
51st Avenue South
Tukwila, Washington
The Galli Group Inc.
13500 Lake City Way NE, Suite 202
Seattle, Washington 98125
206-363-6449
RECEIVED
AUG 21 1995
i j vi+viuNITY
DEVELOPMENT
RECEIVED
AUG 111995
TUKWILA
PUBLIC WORKS
Run Date: 8-2-95
Time of Run: 1245
Run By: rh
Input Data Filename: 1041-3f
Output Filename: 1041-3f.out
Plotted Output Filename: 1041-3f.plt
PROBLEM DESCRIPTION
BOUNDARY COORDINATES
7 Top Boundaries
11 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1
2 100.00 130.00 150.00 135.00 1
3150.00 135.00 450.00 212.00 1
4 450.00 212.00 475.00 215.00 2
5 475.00 215.00 590.00 223.00 2
6 590.00 -223.00 650.00 235.00 2
7 650.00 235.00 690.00 235.00 2
8 170.00 135.00 440.00 140.00 1
9 44000 140.00 450.00 215.00 3
10 450.00 215.00 590.00 207.00 3
11 .590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type (s) of Soil
Soil Total Saturated Cohesion Friction Pore Pressure .Piez.
Type Unit Wt. Unit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 124.0 124.0 .0 14.0 .00 . .0 1
2 124.0 124.0 .0 30.0 .00 .0 1
3 124.0 • 124.0 .0 25.0 .00 .0 1
ANISOTROPIC STRENGTH PARAMETERS
1 soil type (s)
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified = 5
Direction Counterclockwise Cohesion Friction
Range Direction Limit Intercept Angle
No. (deg) (psf) (deg)
1 -16.0 .0 25.0
2 _, 4.0 .0 21.0
3 24.0 .0 17.0
4 44.0 .0 21.0
5 90.0 .0 25.0
.1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A-Horizontal.Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = .0 psf
Janbus Empirical Coef is being used for the case of c=0
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Sliding Block Surfaces, Has Been
Specified.
50 Trial Surfaces Have Been Generated.
4 Boxes Specified For Generation Of Central Block Base
1
Box X -Left Y -Left X -Right Y -Right Height
No. (ft) (ft) (ft) (ft) (ft)
1 230'.00 118.00 250.00 .121.00 30.00
2 275.00 125.00 295:00 129.00 30.00
3. 320.00 132.00 350.00 141.00 30.00
4 370.00 148.00 400.00 156.00 30.00
Following Are Displayed The Ten Most Critical Of The Trial
Failure.Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 15 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 168.65 139.79
2 170.80 137.68
3 185.44 134.44
4 200.31 132.47
5 214.77 128.46
6 229.76 127.88
7 244.72 126.79
8 290.92 137.10
9 324.93 141.32
10 383.06 146.42
11 389.39 160.02
12 399.27 171.31
13 406.41 184.50
14 408.24 199.39
15 408.96 201.47
* * *
.707
* * *
Individual -data on'the 20 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 2.1 354.1 .0 .0 .0 .0 60.2 .0 .0
2 11.0 7213.8 .0 .0 .0 .0 1226.3 .0 .0
3 .1 103.1 .0 .2 .0 .0 17.5 .0 .0
4 3.5 38.6=8.8 .0 259.1 .0 .0 657.7 .0 .0
5 14.9 23147.5 .0 5767.9 .0 .0 3935.1 .0 .0
6 14.5 34604.4, .0 13932.8 .0 .0 5882.7 .0 .0
7 .2 672.5 .0 287.9 .0 .0 114.3 .0 .0.
8 14.8 46498.6 .0 20697.5 .0 .0 7904.8 .0 .0
9 15.0 55755.4 .0 23180.4 .0 .0 9478.4 .0 .0
10 46.2 190756.4 .0 68597.6 .0 .0 32428.6 .0 .0
11 1.4 5772.2 .0 1746.0 .0 .0 981.3 .0 .0
12 32.7 1474-56.1 .0 41001.2 :0 .0 25067.5 .0 .0
13 40.1 2084'70.6 .0 49737.6 .0 .0 35440.0 .0 .0
14 18.1 104995.3 .0 22888.2 .0 .0 17849.2 .0 .0
15 6.3 33243.2 .0 13087.8 .0 .0 5651.4 .0 .0
16 7.4 30230.2 .0 2631.4 .0 .0 5139.1 .0 .0
17 2.5 9037.2 .0 .0 .0 .0 1536.3 .0 .0
18 7.1 19471.6 .0 .0 .0 .0 3310.2 .0 .0
19 1.8 2070.8 .0 .0 .0 .0 352.0 .0 .0
20 .7 83.9 .0 .0 .0 .0 14.3 .0 .0
Failure Surface Specified By 12 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 184.97 143.98
2 196.98 137.93
3 211.31 133.48
4 226.00 130.48
5 239.66 124.28
6 279.65 118.85
7 342.32 128.03
8 392.07 158.26
9 402.66 168.88
10 410.32 181.78
11 420.78 192.53
12 421.01 204.56
***
.726
***
J
Failure Surface Specified By 14 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 169.02 139.88
2 183.45 137.48
3 196.10 129.42
4 208.52 121.01
5 . 223.46 119.59
6 238.46 119.57
7 289.89 123.93
8 322.81 131.35
9 394.42 146.56
10 399.93 160.51
11 407.95 173.19
12 408.16 188.19
13 416.37 200.74
14 418.26 203.85
* * *
.730
***
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 202.35 148.44
2 213.39 141.59
3 226.39 134.11
4 241.34 132.91
5 281.02 136.41
6 325.15 145.32
7 396.93 153.41
8 407.34 164.20
9 413.97 177.66
10 419.02 191.78
11 419.38 204.14
***
.746
* * *
Failure Surface Specified By 1-3 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 172.46 140.76
2 179.98 136.93
3 194.80 134.59
4 206.25 124.90
5 220.69 120.85
6 234.19 114.32
7 285.43 120.24
8 322.86 146.80
9 .389.49 161.56
10 396.27 174.94
11 406.12 186.25
12 415.52 197.94
13 417.29 203.61
***
.758
* * *
Failure Surface Specified By 12 Coordinate Points
Point . X -Surf Y -Surf
No. (ft.) (ft)
1 202.20 148.40
2 210.01 145.17
3 220.63 134.59
4 234.49 128.85
5 291.08 122.08
6 326.71 135.37
7 379.80 152.30
8 388.24 164.70
9 397.24 176.70
10 407.77 187.39
11 413.62 201.20
12 413.98 202.76
* * *
.764
***
Failure Surface Specified By 13 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 185.08 144.00
2 193.92 137.32
3 208.15 132.57
4 219.87 123.21
5 232.40 114.97
6 289.15 118.68
7 348.42 136.28
8 375.49 144.86
9 383.25 157.69
10 393.55 168.60
11 403.77 179.58
12 414.15 190.41
13 417.35 203.62
***
.775
* * *
Failure Surface Specified By 12 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 177.60 142.08
2 180.07 140.85
3 195.00 139.44
4 209.55 135.80
5 220:17 125.20
6 232.54 116.72
7 276.00 121.30
8 336.90 147.21
9 385.31 161.62
10 390.09 175.84,
11 395.01 190.01
12 401.62 199.58
***
.784
Failure Surface Specified By 14 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 170.36 140.23
2 182.16 131.49
3 193.36 121.50
4 207.68 117.04
5 222.00 112.60
6 235.77 106.64
7 276.66 116.84
8 336.83 125.15
9 379.49 149.63
10 381.92 164.43
11 392.05 175.49
12 401.49 187.15
13 409.46 199.86
14 411.67 202.16
***
.786
***
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 200.52 147.97
2 207.76 146.60
3 220.45 138.61
4 234.30 132.84
5 277.96 135.73
1
6 333.10 141.89
7 386.48 156.88,
8 387.74 171.82.
9 392.44 186.07
10 402.61 197.10
11 403.17 199.98
*** .787
***
Y A X I S F T
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W* + + + +
86.25 +
A 172.50 +
*
W*.
9912
5124
9314W.
95314.
..21.
X 258.75 +
.2.0
.3.1
3.5
.914
I 345.00 + 27..
S 431.25 +
517.50 +
W'
.76.. .
.1217.8.
.431131
...2232
*
*
*
603.75
T 690.00 +
w
* *
ANALYSIS TYPE = RANDOM-'
Janbu's empirical coefficient is,an empiricl' correction
low -angle slopes only, and can inci'e-ase the, computed
Do you want to use the Janbu coeffici i\ (Y/N)
;;
/
Enter # that best describes',soil
/-
1. c>0 and 6=o
2. c>0 and, O>0
3. c=0 and O>0
1
type: 3
3
3
3
3
3.
3
: Y
F.S.
factor developed for
by as much as 13%.
** PCSTABLSM **
by
Purdue University
--Slope Stability Analysis --
Simplified Janbu, Simplified Bishop
or Spencer's Method of Slices
Run Date: 5)---.3-5-
Time
)-.3-'~Time of Run: .2'36
Run By: /2,,41-
Input
Z-,4`Input Data Filename: 1041=5a
Output Filename: 1041-5a.out
PlottedL0utput Filename: 1041-5a.plt
PROBLEM( DESCRIPTION lacey house
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
BOUNDARY COORDINATES
9 Top Boundaries
13 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1
2 100.00 130.00 160.00 150.00 1
3 160.00 150.00 403.00 182.00 1
4 403.00 182.00 409.00 201.00 1
5 409.00 201.00 450.00 212.00 1
6 450.00 212.00 475.00 215.00 2
7 475.00 215.00 590.00 223.00 2
8 590.00 223.00 650.00 235.00 2
9 650.00 235.00 690.00 235.00 2
10 170.00 135.00 440.00 140.00 1
11 ' 440.00 140.00 450.00 215.00 3
12 450.00 215.00 590.00 207.00 3
13 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type (s) of Soil
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
Type Unit Wt. Unit,Wt.,Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 124.0 124.0 .0 14.0 .00 .0 1
2 124.0 124.0 .0 30.0 .00 .0 1
3 124.0 124.0 .0 25.0 .00 .0 1
ANISOTROPIC STRENGTH PARAMETERS
1 soil type(s) •
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified = 5
Direction Counterclockwise Cohesion Friction
Range Direction Limit Intercept Angle
No. (deg) (psf) (deg)
1 -16.0 .0 25.0
2 4.0 .0 21.0
3 24.0 .0 17.0
4 44.0 .0 21.0
5 90.0 .0 25.0
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = .0 psf
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Irregular Surfaces, Has Been Specified.
100 Trial Surfaces Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 345.00 ft.
and X = 395.00 ft.
Each Surface Terminates Between X = 450.00 ft..
and X = 500.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = 85.00 ft.
10.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By. The Modified Janbu Method * *
Failure. Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 180.95
,2 404.63 178.26
3 414.55 179.58
4 423.25 184.51
5 430.27 191.63
6 438.41 197.44
7 445.17 204.81
8 452.30 211.82
9 452.63 212.32
***
.519
* * *
Individual data on the 12 slices
Water Water. Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 8.0 1627..3 .0 .0 .0 .0 276.6 .0 .0
2 1.6 1234.9 .0 .0 .0 .0 209.9 .0 .0
3 4.4 8409.1 .0 .0 .0 .0 1429.5 .0 .0
4 5.5 15494.7 .0 .0 .0 .0 2634.1 .0 .0
5 8.7 23313.8 .0 .0 .0 .0 3963.4 .0 .0
6 7.0 15400.6 .0 .0 .0 .0 2618.1 .0 .0
7 8.1 13381.8 .0 .0 .0 .0 2274.9 .0 .0
8 6.8 7274.3 .0 .0 .0 .0 1236.6 .0 .0
9 4.0 2213.0 .0 .0 .0 .0 376.2 .0 .0
10 .8 284.5 .0 .0 .0 .0 48.4 .0 .0
11 2.3 415.1 .0 .0 .0 .0 70.6 .0 .0
12 .3 9.4 .0 .0 .0 .0 1.6 .0 .0
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 383.89 179.48
2 393.65 177.31
3 403.42 179.46
4 412.09 184.44
5 420.97 189.03
6 430.44 192.23
7 439.51 196.46
8 449.21 198.89
9 456.59 205.64
10 464.70 211.48
11 469.70 214.36
***
.557
***
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 180.95
2 403.36 175.46
3 413.25 176.95
4 423.20 178.01
5 430.08 185.26
6 437.52 191.94
7 445.26 198.28
8 453.32 204.19
9 461.41 210.07
10 462.30 213.48
* * *
.608
* * *
Failure Surface Specified By 12 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 372.78 178.02
2 380.61 171.80
3 390.44 169.94
4 400.30 168.29
5 409.72 171.65
6 418.96 175.47
7 428.21 179.27
8 436.12 185.38
9 443.43 192.21
10 449.20 200.37
1
1
11
12
* * *
454.76
455.53
.629
* * *
208.69
212.66
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 389.44 180.21
2 399.07 177.50
3 408.89 175.59
4 417.79 180.14
5 426.77 184.54
6 432.75 192.56
7 441.50 197.40
8 451.39 198.87
9 459.66 204.49
10 468.01 209.99
11 473.20 214.78
***
.634
* * *
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 389.44 180.21
2 396.52 173.15
3 406.15 170.45
4 415.46 174.11
5 423.65 179.86
6 431.94 185.45
7 439.96 191.42
8 447.59 197.88
9 455.39 204.14
10 462.66 211.00
11 464.04 213.68
***
.662
* * *
Failure Surface Specified By 13 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 367.22 177.29
2 376.64 173.92
3 386.49 175.64
4 396.49 175.90
5 406.33 177.65
6 416.33 177.98
7 426.13 179.98
8 434.66 185.19
9 443.92 188.98
10 453.16 192.79
11 461.76 197.89
12 466.81 .206.52
13 468.14 214.18
***
.696
* * *
Failure Surface Specified By 15 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 345.00 174.36
2 354.27 170.60
3 363.80 167.60
4 373.66 165.93
5 383.48 164.02
6 393.48 163.87
7 403.43 162.86
8 413.27 164.64
9 419.74 172.27
10 427.25 178.87
11 434.83 185.38
12 443.00 191.16
13 448.77 199.33
14 454.79 207.31
15 459.90 213.19
.698
***
Failure' Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1
1 378.33 178.75
2 386.65 173.20
3 394.69 167.25
4 404.63 168.33
5 412.44 174.58
6 420.09 181.01
7 428.49 186.44
8 437.42 190.94
9 444.15 198.34
10 451.13 205.50
11 454.59 212.55
* * *
.707
* * *
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 180.95
2 402.43 174.25
3 412.42 174.63
4 422.32 176.08
5 431.72 179.49
6 440.73 183.82
7 448.38 190.27
8 451.70 199.70
9 452.64 209.66
10 453.18 212.38
* * *
.719
***
Y A X I S F
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W* + + + +
86.25 +
*
A 172.50 + W*
X 258.75 +
I 345.00 +
S 431.25 +
517.50 +
F 603.75 +
T 690.00 +
8
W8
.844
.841
.83*.*
...8412
311
*0421*
7722
5*
* *
1
86.25 +
172.50 +
X 258.75 +
I 345.00 +
S 431.25 +
517.50 +
F 603.75 +
690.00 +
W*
*
w*
w
8
W8
..844
...841
...83*.*
...8412
311
*.. 0421*
7722
5*
W
** PCSTABLSM **
* *
by
Purdue University
--Slope Stability Analysis --
Simplified Janbu, Simplified Bishop
or Spencer's Method of Slices
Run Date:
Time of Run:
Run By:
Input Data Filename:
Output Filename:
8-3-95
255
rh
1041-6a
1041-6a.out
�4",74 g 3
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
Plotted Output Filename: 1041-6a.plt
PROBLEM DESCRIPTION lacey house
BOUNDARY COORDINATES
8 Top Boundaries
12 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1
2 100.00 130.00 160.00 150.00 1
3 160.00 150.00 370.00 182.00 1
4 370.00 182.00 450.00 212.00 1
5 450.00 212.00 475.00 215.00 2.
6 475.00 215.00 590.00 223.00 2
7 590.00 223.00 650.00 235.00 2
8 650.00 235.00 690.00 235.00 2'
9 170.00 135.00 440.00 140.00 1
10 440.00 140.00 450.00 215.00 3
11 450.00 215.00 590.00 207.00 3
12 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type(s) of Soil
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
Type Unit Wt. Unit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 124.0 124.0 .0 14.0 .00 .0 1
2 124.0 124.0 .0 30.0 .00 .0 1
3 124.0 124.0 .0 25.0 .00 .0 1
ANISOTROPIC STRENGTH PARAMETERS
1. soil type(s)
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified = 5
Direction Counterclockwise Cohesion Friction
Range Direction Limit Intercept Angle
No. (deg) (psf) (deg)
2
3
-16.0 .0 25.0
4.0 .0 21.0
24.0 .-0 17.0
44.0 .0 21.0
90.0 .0 25.0
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = .0 psf
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Irregular Surfaces, Has Been Specified.
' 100 Trial Surfaces Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 340.00 ft.
and X = 370.00 ft.
Each Surface Terminates Between , X = 450.00 ft.
and X = 500.00 ft.
Unless Further Limitations. Were Imposed, The Minimum Elevation
At Which.A Surface Extends Is Y = 85.00 ft.
15.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg..
Following Are Displayed The Ten, Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 360.00 180.48
2 374.96 181.63
3 389.59 184.92
4 404.45 186.95
5 418.90 190.98
6 433.55 194.22
7 446.52 201.75
8 459.09 209.93
9 461.63 213.40
***
.631
***
Individual data on the 11 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg
1 10.0 468.0 .0 .0 .0 .0 79.6 .0 .(
2 5.0,. 918.0 .0 .0 .0 .0 156.1 .0 .(
3 14.6 6044.4 .0 .0 .0 .0 1027.6 .0 .(
4 14.9 11427.6 .0 .0 .0 .0 1942.7 .0 .(
5 14.4 15528.4 .0 .0 .0 .0 2639.8 .0 .(
6 14.6 19040.3 .0 .0 .0 .0 3236.8 .0 .(
7 13.0 16527.5 .0 .0 .0 .0 2809.7 .0 . (
8 1.9 2'022.1 .0 .0 .0 .0 343.8 .0 .(
9 1.6 1630.7 .0 .0 .0 .0 277.2 .0 .0
10 9.1 6278.0 .0 .0 .0 .0 1067.3 .0 .0
11 2.5 496.8 .0 .0 .0 .0 84.5 .0 .0
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 360.00 180.48
2 374.62 177.13
3 389.29 180.29
4 403.81 184.02
5 417.45 190.28
6 431.12 196.45
7 445.01 202.10
8 456.20 - 212.09
9 456.56 212.79
***
.643
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 370.00 182.00
2 385.00 181.86
3 399.57 185.41
4 412.14 193.59
5 427.14 193.71
6 439.67 201.96
7 453.06. 208.73
8 455.35 212.64
***
.706
***
Failure Surface Specified By 9 Coordinate Points
Point X -Surf
No. (ft)
1 353.33
2 366.65
3 381.58
4 395.48
5 410.01
6 423.20
c
Y -Surf
(ft)
179.46
172.56
174.02
179.66
183.39
190.54
7 435.58 199.01
8 447.77 207.75
9 455.30 212.64
***
.723
* * *
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 343.33 177.94
2 358.32 177.25
3 373.14 174.93
4 388.07 173.48
5. 403.07 173.42
6 417.16 178.57
7 430.91 184.56
8 444.25 191.42
9 455.72 201.09
10 466.70 211.31
11 467.86 214.14
***
.751
***
Failure Surface Specified By 11 Coordinate Points
Point X -Surf .Y -Surf
No. (ft) (ft)
1 360.00 180.48
2 374.69 177.42
3 389.30 174.04
4 404.26 175.09
5 419.20 176.47
6 433.77 180.05
7 446.05 188.66
8 '458.63 196.84
9 470.95 205.39
10 483.52 213.57
11 484.85 215.69
* * *
.771 •***
1
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 353.33 179.46
2 367.81 175.55
3 382.78 174.50
4 397.75 173.61
5 412.27 177.37
6 426.80 181.08
7 441.30 184.95
8 454.27 192.48
9 458.38 206.90
10 460.21 213.22
***
.793
***
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 350.00 178.95
2 363.44 172.29
3 377.50 167.06
4 391.66 172.01
5 405.95 176.55
6 420.48 180.26
7 433.03 188.49
8 446.08 195.88
9 455.32 207.70
10 457.97 212.96
* * *
.808
***
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 356.67 179.97
2 371.65 179.28
3 386.47 176.97
4 401.40 175.51
5 416.40 175.45
6 430.49 180.60
7 444.24 186.59
8 457.58 193.45
9 469.05 203.12
10 480.03 213.34
11 480.88. 215.41
* * *
.809
***
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 343.33 177.94
2 356.93 1711.60
3 371..22 176.16
4 386.20 176.87
5 400.48 181.48
6 415.46 182.16
7 427.40 191.24
8 438.61 201.20
9 453.29 204.29
10 463.92 213.67
***
.810
* * *
Y A X I S F T
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W* + + + +
86.25 +
W*
*
A 172.50 + W*
X 258.75 +
345.00 + . 5
.W81
..84*
41
521
641
S 431.25 + 531
*. 7514*
7511
6*
6
517.50 +
F 603.75 +
T 690.00 + W
1
*
A 172.50 + W*
X 258.75 +
)
I 345.00 + . 5
.W81
..84*
41
521
641
S 431.25 + 531
*.. 7514*
7511
6*
6
527.50 +
F 603.75 +
T 690.00 +
W
** PCSTABL5M **
* *
by
Purdue University
--Slope Stability Analysis --
Simplified Janbu, Simplified Bishop
or Spencer's Method of Slices
Run Date:
Time of Run:
Run By:
Input Data Filename:
Output Filename:
Plotted Output Filename:
1041-7a
1041-7a.out
1041-7a.plt
THE GALLI GROUP
ENGINEERS & CONSULTANTS •
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
PROBLEM DESCRIPTION lacey house
BOUNDARY COORDINATES
8 Top Boundaries
10 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1.
2 100.00 130.00 160.00 150.00 1
3 .160.00 150.00 360.00 181.00 1
4 360.00 181.00 451.00 207.00 1
5 451.00 207.00 475.00 215.00 3
6 475.00 215.00 590.00 223.00 2
7 590.00 223.00 650.00 235.00 2
8 650.00 235.00 690.00 235.00 2
9 475.00 215.00 590.00 207.00 3
10 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type (s) of Soil
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
Type Unit Wt. .;nit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 124.0 124.0 .0 14.0 .00 .0 1
2 124.0 124.0 .0 30.0 .00 .0 1
3 124.0 124.0 .0 25.0 .00 .0 1
ANISOTROPIC STRENGTH PARAMETERS
1 soil type(s)
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified = 5
Direction Counterclockwise Cohesion Friction
Range ' Direction Limit Intercept Angle
No. (deg) (psf) (deg)
1 -16.0 .0 25.0
2 4.0 .0 21.0
3 24.0 .0 17.0
4 44.0 .0 21.0
5 X90.0 .0 25.0
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = .'0 psf
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Irregular Surfaces, Has Been Specified.
100 Trial Surfaces Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 345.00 ft.
and X = 420.00 ft.
Each Surface Terminates Between X = 470.00 ft.
and X = 530.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = 85.00 ft.
.15.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 191.00
2 409.97 191.96
3 424.96 191.57
4 438.82 197.31
5 452.88 202.54
6 467.24 206.88
7 478.41 215.24
***
.799
***
Individual data on the 9 slices
Water Water Tie Tie Earthquake
Force Force_ Force Force Force Surcharge
Slice Width Weight Top Bot ' Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 15.0 3074.1 .0 .0 .0 .0 522.6 .0 .0
2 15.0 10505.9 .0 .0 .0 .0 1786.0 .0 .0
3 13.9 12197.6 .0 .0 .0 .0 2073.6 .0 .0
4 12.2 8582.6 .0 .0 .0 .0 1459.0 .0 .0
5 1.9 1196.0 .0 .0 .0 .0 203.3 .0 .(
6 14.4 9457.4 .0 .0 .0 .0 1607.8 .0 .0
7 7.8 3776.3 .0 .0 .0 .0 642.0 .0 .(
8 2.8 475.1 .0 .0 .0 .0 80.8 .0 .(
9 .6 14.1 .0 .0 .0 .0 2.4 .0 .(
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 191.00
2 409.52 187.22
3 424.46 188.51
4 439.22 191.17
5 453.54 195.65
6 467.54 201.04
7 474.98 214.06
8 475.45 215.03
***
.823
***
Failure Surface Specified By 6 Coordinate Points
Point. X -Surf Y -Surf
No. (ft) (ft)
1 411.67 195.76
2 426.51 193.60
3 441.35 1.95.78
4 456.14 198.27
5 468.47 206.81
6 477.89 215.20
* * *
.830
* * *
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 191.00
2 409.96 189.91
3 424.96 189.72
4 438.75 195.61
5 453.20 199.65
6 467.96 202.34
7 477.38 214.00
8 478.78 215.26
* * *
:856
* * *
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 191.00
2. 409.23 186.25
3 424.16 187.69
4 438.86 190.67
5 452.79 196.24
6 466.90 201.34
7 480.46 207.74
8 493.77 214.66
9 496.37 216.49
* * *
.870
***
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft). (ft)
1 361.67 181.48
2 376.65 182.20
3 390.09 188.85
4 405.08 188.16
5 420.02 189.44
6 434.77 192.20
7 449.48 195.13
8 462.67 202.27
9 477.59 203.87
10 490.01 212.29
11 499.48 216.70
***
.878
* * *
Failure Surface Specified By 5 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 420.00 198.14
2 434.65 194.93
3 449.07 199.08
4 463.56 202.97
5 471.69 213.90
* * *
.884
* * *
Failure Surface_. Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 378.33 186.24
2 393.25 184.64
3 408.05 182.21
4 422.95 180.46
5 437.85 182.20
6 449.97 191.03
7 462.16 199.78
8 472.93 210.22
9 476.52 215.11
* * *
.904
***
Failure Surface Specified By 8 Coordinate_ Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 395.00 191.00
2 409.96 189.95
3 424.94 189.08
4 439.92 188.34
5 454.27 192.70
6 468.01 .198.73
7 480.17 207.50
8 489.92 216.04
* * *
.926
***
Failure Surface. Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 378.33 186.24
2 392.35 180.90
3 406.22 186.62
4 420.31 191.76
5 435.30 192.28
6 448.91 198.58
7 463.76 200.73
1
8
9
***
477.95
483.87
.936
***
205.57
215.62
Y A X I S F T
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W*. ,+ + + +
86.25 +
W*
A 172.50 +
X 258.75 +
I 345.00 +
*
W -
.W.*
68
81
_ 82
813
S 431.25 + 817
21*
917
21*
5
5
517.50 +
F 603.75 +
1
1
** PCSTABL5M **
by
Purdue University
--Slope Stability Analysis -
Simplified Janbu, Simplified Bishop
or Spencer's Method of Slices
Run Date:
Time of Run:
Run By:
Input Data Filename: 1041-8a
Output Filename: , 1041-8a.out
Plotted Output Filename: 1041-8a.plt
PROBLEM DESCRIPTION lacey house
BOUNDARY COORDINATES
9 Top Boundaries
11 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1
2 100.00 130.00 160.00 150.00 1
3 160.00 150.00 360.00 182.00 1
4 360.00 182.00 390.00 196.00 1
5 390.00 196.00 451.00 206.00 1
6 451.00 206.00 480.00 216.00 3
7 480.00 216.00 590.00 223.00, 2
8 590.00 223.00 650.00 235.00 2
9 650.00 235.00. 690.00 235.00 2
10 475.00 215.00 590.00 207.00 3
11 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type (s) of Soil
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
Type Unit Wt. Unit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1
1 124.0 124.0 .0 14.0 .00 .0 1
2 124.0 124.0 .0 30.0 .00 .0 1
3 124.0 124.0 .0 25.0 .00 .0 1
ANISOTROPIC STRENGTH PARAMETERS
1 soil type()
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified = 5
Direction Counterclockwise Cohesion Friction
Range Direction Limit Intercept Angle
No. (deg) (psf) (deg)
1 -16.0 .0 25.0
2 4.0 .0 21.0
3 24.0 .0 17.0
4 44.0 .0 21.0
5 90.0 .0 25.0
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Pbints
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00. 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = 0 psf
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Irregular Surfaces, 'Has Been Specified.
100 Trial Surfaces. Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 345.00 ft.
and X = 430.00 ft.
Each Surface Terminates Between X = 490.00 ft.
and X = 550.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = 85.00 ft.
20.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 363.89 183.82
2 382.86 177.48
3 402.77 179.40
4 422.37 183.37
5 440.94 190.80
6 459.75 197.59
7 477.83 206.14
8 495.58 215.36
9 498.13 217.15
***
.896 ***
Individual data on the 13 slices
Water Water Tie Tie Earthquake
Force .Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 19.0. 17859.8 .0 .0 .0 .0 3036.2 .0 .0
2 7.1 14610.9 .0 .0 .0 .0 2483.9 .0 .0
3 12.8 28911.1 .0 .0 .0 .0 4914.9 .0 .0
4 19.6 44516.9 .0 .0 .0 .0 7567.9 .0 .0
5 18.6 36255.2 .0 .0 .0 .0 6163.4 .0 .0
6 10.1 15666.6 .0 .0 .0 .0 2663.3 .0 .0
7 8.8 12472.6 .0 .0 .0 .0 2120.3. .0 .0
8 15.2 19757.8 .0 .0 .0 .0 3358.8 .0 .0
9 2.8 3265.2 .0 .0 .0 .0 555.1 .0 .0
10 2.2 2397.5 .0 .0 .0 .0 407.6 .0 .0
11 12.5 9129.2 .0 .0 .0 .0 1552.0 .0 .0
12 3.0 877.5 .0 .0 .0 .0 149.2 .0 .0.
13 2.5 257.0 .0 .0 .0 .0 43.7 .0 .0
Failure Surface Specified By 5 Coordinate Points
Point X -Surf
No. (ft)
1 420.56
2 440.40
3 460.33
4 479.8
5 493.49
*** 1.018
* * *
Y -Surf
(ft).
201.01
203.49
205.21
209.69
216.86
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 373.33 188.22
2 393.21 190.49
3 413.18 189.42
4 433.03 187.04
5 452.40 192.02
6 470.27 201.01
.7 488.29 209.69
8 507.54 215.11
9 509.58 217.88
* * *
1.060
***
Failure Surface Specified By 12 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 345.00 179.60
2 359.37 165.69
3 377.67 157.63
4 397.21 153.35
5 416.69 157.90
6 436.52 160.50
7 456.51 160.94
8 472.65 172.76
9 487.09 186.59
10 501.20 200.77
11 515.89 214.34
12 519.89 218.54
***
1.074
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 345.00 179.60
2 359.76 166.10
3 379.75 166.63
4 399.56 163.88
5 419.55 164.68
6 439.30 167.84
7 456.77 177.57
8 475.73 183.94
9 492.12 195.39
10 504.93 210.75
11 507.95 217.78
***
1.076
* * *
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 382.78 192.63
2 400.50 183.35
3 420.43 184.99
4 440.37 186.59
5 459.86 191.06.
6 476.44 202.24
7 491.88 214.95
8 492.57 216.80
* * *
1.082
***
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 401.67 197.91
2 421.16 193.44
3 441.16 193.40
4 461.02 195.76
5 479.50 203.40
6 495.41 215.52
7 496.58 217.05
* * *
1.083
* * *
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 392.22 196.36
2 411.70 191.82
3 431.48 188.85
4 451.34 191.23
5 469.41 199.80
6 487.40 208.53
7 506.18 215.42
8 508.76 217.83
* * *
1.101
***
Failure Surface Specified By 5 Coordinate Points
Point X -Surf Y -Surf
1
No. (ft) (ft)
1 430.00 202.56"
2 450.00 202.43
3 469.79 205.30
4 489.12 210.44
5 494.22 216.91
***
1.106
* * *
Failure Surface Specified By 6 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 411.11 199.46
2 430.94 196.83
3 450.69 193.70
4 467.85 203.98
5 485.30 213.76
6 492.78 216.81
* * *
1.116
* * *
y A X I S F T
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W* + + + +
86.25 +
W*
A 172.50 + W
X 258.75 +
*
I 345.00 + 4
- W.*
- 453
- ....13*
- .45.1.7
- ▪ .45.132
S 431.25 + . ..439
- . ..519*
- 4 5612
- ..45.31*
4531
- 451
517.50 + 4
* *
F 603.75 +
T 690.00 + W
--Slope Stability Analysis --
Simplified Janbu, Simplified Bishop
or Spencer's Method of Slices
Run Date:
Time of Run:
Run By:
Input Data Filename:
Output Filename:
Plotted Output Filename:
1041-9b
1041-9b.out
1041-9b.plt
PROBLEM DESCRIPTION lacey house
BOUNDARY COORDINATES
10 Top Boundaries
12 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 .1
2 100.00 130.00 160.00 150.00 1
3 160.00 150.00 358.00 181.00 1
4 358.00 181.00 364.00 186.00 1
5 364.00 186.00 451.00 200.00 1
6 451.00 200.00 489.00 206.00 3
7 489.00 206.00 498.00 217.00 2
8 498.00 217.00 590.00 223.00 2
9 590.00 223.00 650.00 235.00 2
10 650.00 235.00 690.00 235.00 2
11 489.00 206.00 590.00 207.00 3
12 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type (s) of Soil
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
Type Unit Wt. Unit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 124.0 124.0 .0 14.0 .00 .0 1
2 124.0 124.0 .0 30.0 .00 .0 1
3 124.0 124.0 .0 25.0 .00 .0 1
ANISOTROPIC STRENGTH PARAMETERS
1 soil type(s)
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified = 5
Direction Counterclockwise Cohesion Friction
Range Direction Limit Intercept Angle
No. (deg) (psf) (deg)
1 -16.0 .0 25.0
2 . 4.0 .0 21.0
3 24.0 .0 17.0
4 44.0 .0 21.0
5 90.0 .0 25.0
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000) Has Been Assigned
Cavitation Pressure = .0 psf
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Irregular Surfaces, Has Been Specified.
100 Trial Surfaces Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 400.00 ft.
and X = 450.00 ft.
Each Surface Terminates Between X = 510.00 ft.
and X = 550.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = 85.00 ft.
15.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 438.89 198.05
2 453.79 196.36
3 468.79 196.00
4 483.22 200.09
5 497.17 205.61
6 509.87 213.58'
7 513.58 218.02
***
1.020
***
Individual data on the 10 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 12.1 2492.9 .0 .0 .0 .0 423.8 .0 .0
2 2.8 1281.5 .0 .0 .0 .0 217.9 .0 0
3 15.0 10118.4 .0 .0 .0 .0 1720.1 .0. 0
4 14.4 10558.8 .0 .0 .0 .0 1795.0 .0 0
5: 5.8 3087.6 .0 .0 .0 .0 524.9 .0 0
6 8.2 7094.2 .0 .0 .0 .0 1206.0 .0 0
7 .8 1008.5 .0 .0 .0 .0 171.4 .0 0
8 .1 83.6 .0 .0 .0 .0 14.2 .0 0
9 11.9 11088.8 .0 .0 .'0 .0 1885.1 .0 0
10 3.7 962.5 .0 .0 .0 .0 163.6 .0 0
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 444.44 198.95
2 459.42 199.80
3 474.40 200.57
4 489.16 203.25
5 503.28 208.32
6 517.10 214.15
7 526.07 218.83
* * *
1.039 ***
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 422.22 195.37
2 435.86 189.13
3 450.80 190.46
4 465.66 192.54
5 480.13 196.48
6 495.12 196.96
7 506.96 206.17
8 518.98 215.14
9 519.82 218.42
* * *
1.067
***
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 400.00 191.79
2 414.98 191.00
3 429.97 190.34
4 444.95 190.90
5 459.95 190.78
6 ;474.58 194.11
7 489.04 198.10
8 503.56 201.87
9 512.65 213.81
10 512.88 217.97
***
1.100
***
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 444.44 198.95
2 459.19 196.22
3 473.28 191.05
4 488.27 191.49
5 500.45 200.24
6 511.03 210.88
7 524.64 217.18
8 525.89 218.82
***
1.103
***
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 450.00 199.84
2 463.77 193.90
3 478.28 197.73
4 492.66 202.00
5 506.80 206.98
6 519.52 214.94
7 525.33 218.78
***
1.107
***
1
1
Failure Surface Specified By 6 Coordinate Points
Point X -Surf
No. (ft)
1 450.00
2 463.38
3 478.22
4 491.84
5 505.52
6 515.47
*** 1.112
***
Y -Surf
(ft)
199.84
193.06
195.28
201.57
207.72
218.14
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 444.44 198.95
2 457.18 191.02
3 472.18 191.38
4 487.17 190.95
5 501.33 195.90
6 511.92 206.52
7 521.72 217.88
8 522.28 218.58
* * *
1.137
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 433.33 197.16
2 448.33 196.73
3 463.25 195.17
4 478.25 195.29
5 492.81 198.87
6 507.65 201.08
7 517.91 212.02
8 518.00 218.30
1.151
***
- ..43
4311. 25 +
5150 +
F 603.75 +
T 690.00 +
39
• 3*
31
• 51
51*
41*
51
2
W
1
1
** PCSTABLSM
**
by
Purdue University
--Slope Stability Analysis -'-
Simplified Janbu, Simplified Bishop
or Spencers Method of Slices
Run Date:
Time of Run:
Run By:
Input Data Filename: 1041-10a
Output Filename: ' 1041-10a.out
Plotted Output Filename: 1041-10a.plt
PROBLEM DESCRIPTION lacey house
BOUNDARY COORDINATES
12 Top Boundaries
14 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right. Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1
2 100.00 130.00 160.00 150.00 1
3 160.00 150.00 358.00 181.00 1
4 358.00 181.00 364.00 186.00 1
5 364.00 186.00 439.00 198.00 1
6 439.00 198.00 451.00 202.00 1
7 451.00 202.00 489.00 208.00 3
8 489.00 208.00 505.00 210.00 2
9 505.00 210.00 514.00 218.00 2
10 514.00 218.00 590.00 223.00 2
11 590.00 223.00 650.00 235.00 2
12 650.00 235.00 690.00 235.00 2
13 489.00 208.00 590.00 207.00 3
14 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type (s) of Soil
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
1
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
,4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = .0 psf
A Critical Failure Surface Searching. Method, Using A Random
Technique For Generating Irregular Surfaces, Has Been Specified.
100 Trial Surfaces Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 460.00 ft.
and X = 490.00 ft.
Each Surface Terminates Between X = 520.00 ft.
and X = 570.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = 85.00 ft.
10.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical '
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 483.33 207.11
2 492.53 203.19
3 502.44 204.57
4 512.34 205.97
5 521.15 210.69
6 527.90 218.07
7 528.86 218.98
*** 1.093
• * * *
Individual data on the 10 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 5.7 1161.8 .0 .0 .0 .0. 197.5 .0 .0
2 3.5 1876.2 .0 .0 .0 .0 318.9 .0 .0
3 9.9 6364.5 .0 .0 .0 .0 1082.0 .0 .0
4 2.6 1616.5 .0 .0 .0 .0 274.8 .0 .0
5 7.3 7110.0 .0 .0 .0 .0 1208.7 .0 .0
6 1.7 2232.8 .0 .0 .0 .0 379.6 .0 .0
7 1.6 2181.1 .0 .0 .0 .0 370.8 .0 .0
8 5.5 6208.7 .0 .0 .0 .0 1055.5 .0 .0
9 6.8 3608.0 .0 .0 .0 .0 613.4 .0 .0
10 1.0 50.0 .0 .0 .0 .0 8.5 .0 .0
Failure Surface Specified By 6 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 486.67 207.63
2 496.54 206.03
3 506.50 206.89
4 516.10 209.69
5 525.57 212.90
6 531.14 219.13
* * *
1.138 ***
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 466.67 204.47
2 476.46 202.45
3 486.34 204.01
4 495.95 206.77
5 505.87 208.04
6 515.63 210.23
7 521.64 218.22
8 521.76 218.51
* * *
1.145
* * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 486.67 207.63
2 494.67 201.64
3 504.54 200.04
4 513.78 203.87
5 520.45 211.32
6 527.98 217.90
7 529.14 219.00
***
1.168
***
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 466.67 204.47
2 476.66 204.19
3 486.61 203.15
4 496.61 203.23
5 506.32 205.61
6 516.21 207.09
7 523.05 214.38
8 523.11 218.60
* * *
1.168
***
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 470.00 205.00
2 479.47 201.78
3 489.44 202.60
4 499.41 203.31
5 508.49 207.50
6 517.31 212.21
7 525.86 217.40
8 526.51 218.82
* * *
1.169
* * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 473.33 205.53
2 483.33 205.13
3 492.86 202.11
4 502.45 199.28
5 511.52 203.48
6 517.37 211.59
7 521.77 218.51
***
1.173
* * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 480.00 206.58
2 489.18 202.62
3 498.85 205.17
4 508.44 208.02
5 517.87 211.34
6 526.34 216.65
7 529.98 219.05
* * *
1.184
* * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 486.67 207.63
2 496.50 205.80
3 505.73 201.95
4 515.02 205.64
5 524.91 207.12
6 532.06 214.12
7 535.93 219.44
1
* * *
1.194
* * *
Failure Surface Specified By 6 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 490.00 208.13
2 498.96 203.69
3 508.87 202.34
4 518.67 204.32
5 524.53 212.43
6 526.12 218.80
* * *
Y
1.195
* * *
A X I S F T
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W* + + + +
86.25 +
A 172.50 +
X 258.75 +
I 345.00 +
W*
W
*
W **
S 431.25 +
517.50 +
F 603.75 +
T 690.00 +
W
* *
** PCSTABL5M ** vG� SLC
by
Purdue University
--Slope Stability Analysis --
Simplified Janbu, Simplified Bishop
or Spencer's Method of Slices
Run Date-:
Time of Run:
• Run By:
Input Data Filename: 1041-11
Output Filename: 1041-11.out
Plotted Output Filename: 1041-11.plt
PROBLEM'DESCRIPTION lacey house
BOUNDARY COORDINATES
12 Top Boundaries
14 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1
2 100.00 130.00 160.00 150.00 1
3 160.00 150.00 358.00 181.00 1
4 358.00 181.00 364.00 186.00 1
5 364.00 186.00 439.00 198.00 1
6 439.00 198.00 451.00 202.00 1
7 451.00 202.00 489.00 210.00 2
8 489.00 210.00 523.00 213.00 2
9 523.00 213.00 529.00 219.00 2
10 529.00 219.00 590.00 223.00 2
11 590.00 223.00 650.00 235.00 2
12 650.00 235.00 690.00 235.00 2
13 489.00 208.00 590.00 207.00 3
14 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Types) of Soil
THE GALLI GROUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE, SUITE 202
SEATTLE, WA 98125
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
1
1
Type Unit Wt Unit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 124.0 124.0 .0 14.0 .00 .0 1
2 124.0 124.0 .0 30.0 .00 .0 1.
3 124.0 124.0 .0 25.0 .00 .0 1
ANISOTROPIC STRENGTH PARAMETERS
1 soil type(s)
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified = 5
Direction Counterclockwise Cohesion Friction
Range Direction Limit Intercept Angle
No. (deg) (psf) (deg)
1 -16.0 .0 25.0
2 4.0 .0 21.0
3 24.0 .0 17.0
4 44.0 .0 21.0
5 90.0 .0 25.0
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = 0 psf
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Irregular Surfaces, Has Been Specified.
100 Trial Surfaces Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 470.00 ft.
and X = 500.00 ft.
Each Surface Terminates Between X = 535.00 ft.
and X = 560.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = 85.00 ft.
10.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation..
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 496.67 210.68
2 506.26 207.85
3 516.23 207.09
4 526.18 206.05
5 535.42 209.87
6 540.51 218.48
7 541.05 219.79
***
1.342
***
Individual data on the
10 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm -Tan Hor .Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 9.6 2184.3 .0 .0 .0 .0 371.3 .0 .0
2 .3 144.8 .0 .0 .0 .0 24.6 .0 .0
3 9.7 5411.4 .0 .0 .0 .0 919.9 .0 :0
4 6.8 5008.4 .0 .0 .0 .0 851.4 .0 .0
5 3.2 3297.5 .0 .0 .0 .0 560.6 .0 .0
6 2.8 3834.8 .0 .0 .0 .0 651.9 .0 .0
7 .9 1312.7 .0 .0 .0 .0 223.2 .0 .0
8 5.5 7175.3 .0 .0 .0 .0 1219.8 .0 .0
9 5.1 3414.5 .0 .0 .0 .0 580.5 .0 .0
10 .5 42.6 .0 .0 .0 .0 7.2 .0 .0
Failure Surface Specified By 6 Coordinate Points
Point X -Surf
No. (ft)
1 500.00
2 508.90
3 518.90
4 528.42
5 536.64
6. 539.36
*** 1.348 ***
Y -Surf
(ft)
210.97
206.41
206.46
209.53
215.22
219.68
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. .(ft) (ft)
1 483.33 208.81
2 .492.77 205.51
3 502.77 205.57
4 512.77 205.77
5 522.77 205.77
6 C 531.26 211.06
7 537.66 218.75
8 538.10 219.60
***
1.371
* * *
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 490.00 210.09
2 499.65 207.45
3 509.40 205.26
4 519.33 204.05
5 529.33 204.22
6 537.20 210.39
7 542.94 218.57
8 544.04 219.99
***
1.376
***
Failure Surface Specified By 6 Coordinate Points
Point X -Surf
No. (ft)
1 500.00
2 508.91
3 518.69
4 528.20
5 534.90
6 535.47
*** 1.398
***
Y -Surf
(ft)
210.97
206.43
208.53
211.63
219.05
219.42
Failure Surface Specified By 5 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 500.00 210.97
2 509.73 208.65
3 519.71 209.23
4 528.38 214.21
5 536.32 219.48
***
1
1.399
* * *
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) • (ft)
1 473.33 206.70
2 483.19 208.40
3 493.00 206.46
4 502.78 208.54
5 512.78 208.30
6 521.92 204.24
7 531.67 .206.45
8 540.31 211.49
9 546.82 219.07
10 548.75 220.30
***
1.420
***
Failure Surface Specified By 9 Coordinate Points
Point X -Surf . Y -Surf
No. (ft) (ft)
1 490.00 210.09
2 499.75 207.85
3 509.70 206.90
4 519.66 205.94
5 529.62 205.16
6 . 539.03 208.56
7 548.12 212.72
8 554.97 220.01
9 555.42 220.73
* * *
1.428
***
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No.. (ft) (ft)
1 496.67 210.68
2 505.74 206.47
3 515.72 205.85
4 525.12 209.26
5 534.46 212.84
6 543.53 217.05
7 548.47 220.28
1
***
1.437
***
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 486.67 209.51
2 494.93 203.87
3 504.84 202.51
4 514.77 203.70
5 524.66 205.17
6 533.07 210.58
7 540.61 217.15
8 543.30 219.94
* * *
1.446,
***
Y A X I S F T
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W* + + + +
86.25 +
A 172.50 +
X 258.75 +
I 345.00 +
W*
W
*
W
W **
S 431.25 +
517.50 +
F 603.75 +
T 690.00 +
*
W
* *
Run Date:
Time of Run:
Run By:
Input Data Filename: 1041-12
Output Filename: 1041-12.out
Plotted Output Filename: 1041-12.plt
PROBLEM DESCRIPTION lacey house
BOUNDARY COORDINATES
12 Top Boundaries
14 Total Boundaries
Boundary X -:-Left Y-Le.ft X -Right Y -Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 .00 110.00 100.00 130.00 1
2 100.00 130.00 160.00 150.00 1
3 160.00 150.00 358.00 181.00 1
4 358.00 181.00 364.00 186.00 1-
5 364.00 186.00 439.00 198.00 1
6 439.00 198.00 451.00 202.00 1
7 451.00 202.00 489.00 210.00 2.
8 489.00 210.00 523.00 213.00 2
9 523.00 213.00 529.00 219.00 2
10 529.00 219.00 590.00 223.00 2
11 590.00 223.00 650.00 235.00 2
12 650.00 235.00 690.00 235.00 2
13 489.00 208.00 590.00 207.00 3
14 590.00 207.00 690.00 235.00 3
ISOTROPIC SOIL PARAMETERS
3 Type (s) of Soil
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
Type Unit Wt. Unit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 124.0 124.0 .0 14.0 .00 .0 1
2 124.0 124.0 .0 30.0 .00 .0 1
3 124.0 124.0 .0 25.0 .00 .0 1.
ANISOTROPIC STRENGTH PARAMETERS
Thc. IaHLLI l rLiUP
ENGINEERS & CONSULTANTS
13500 LAKE CITY WAY NE. SUITE 202
1 soil type(s)
Soil Type 1 Is Anisotropic
Number Of Direction Ranges Specified =
Direction Counterclockwise Cohesion Friction
Range Direction Limit Intercept Angle
No. (deg) (psf) (deg)
1 -16.0 .0 25.0
2 4.0 .0 21.0
3 24.0 .0 17.0
4 44.0 .0 21.0
5 90.0 .0 25.0
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 6 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 .00 100.00
2 100.00 125.00
3 170.00 130.00
4 215.00 150.00
5 365.00 165.00
6 690.00 200.00
A Horizontal Earthquake Loading Coefficient
Of .170 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of .000 Has Been Assigned
Cavitation Pressure = .0 psf
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Irregular Surfaces, Has Been Specified.
1,00 Trial Surfaces Have Been Generated.
10 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 470.00 ft.
and X = 540.00 ft.
Each Surface Terminates Between X =x590.00 ft.
and X = 680.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = 85.00 ft.
25.,00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 10.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They. Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Janbu Method * *
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 485.56 209.27'
2 504.39 192.84
3 529.18 189.62
4 554.13 191.23
5 578.33 197.52
6 602.45 204.07
7 624.72 215.45
8 646.69 227.36
9 655.25 235.00
***
1.623
* * *
Individual data on the 14 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft (m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg
1 3.4 796.7 .0 .0 .0 .0 135.4 .0 .0
2 15.4 21234.9 .0 .0 .0 .0 3609.9 .0 .0
3 18.6 47418.2 .0 .0 .0 .0 8061.1 .0 .0
4 6.0 19317.3 .0 .0 .0 .0 3283.9 .0 .0
5 .2 668. .0 .0 .0 .0 113.6 .0 .0
6 24.9 90970.5 .0 .0 .0 .0 15465.0 .0 .0
7 24.2 81209.8 .0 .0 .0 .0 13805.7 .0 .0
8 11.7 34034.8 .0 .0 .0 .0 5785.9 .0 .0
9 12.5 33765.8 .0 .0 .0 .0 5740.2 .0 .0
10 22.3 49577.1 .0 .0 .0 .0 8428.1 .0 .0
11 4.9 8235.0 .0 .0 .0 .0 1400.0 .0 .0
12 17.1 21019.2 .0 .0 .0 .0 3573.3 .0 .0
13 3.3 2391.7 .0 .0 .0 .0 406.6 .0 .0
14 5.3 1525.4 .0 .0 .0 .0 259.3 .0 .0
Failure Surface Specified By 6 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 485.56 209.27
2 507.63 197.54
3 532.61 196.64
4 555.33 207.08
5 578.08 217.43
6 598.10 224.62
1.626
***
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 493.33 210.38
2 516.29 200.49
3 538.93 189.88
4 562.96 196.78
5 587.36 202.23
6 612.01 206.40
7 635.11 215.95
8 650.97 235.00
* * *
1.631
* * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 477.78 207.64
2 502.73 206.06
3 527.57 203.24
4 552.47 205.40
5 576.62 211.88
6 600.39 219.62
7 606.21 226.24
* * *
1.636
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 477.78 207.64
2 500.30 196.79
3 524.75 191.57
4 548.16 200.34
5 572.36 206.62
6 592.55 221.36
7 595.93 224.19
* * *
1.642
* * *
Failure Surface Specified By 10 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 485.56 209.27
2 504.46 192.91
3 527.99 184.49
4 '552.85 181.83
5 577.80 183.46
6 602.38 187.99
7 625.99 196.22
8 647.79 208.46
9 662.94 228.34
10 666.10 235.00
***
1
1.644
* * *
1
Failure Surface Specified By 8 Coordinate Points
Point X -Surf .Y -Surf
No. (ft) (ft)
1 508.89 211.75
2 533.39 206.76
3 558.38 207.24
4 583.30 209.26
5 608.22 211.21
6 632.87 215.41
7 653.62 229.35
8 655.56 235.00
***
1.645
***
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 477.78 207.64
2 502.56 204.36
3 527.54 203.22
4 552.12 198.70
5 575.04 208.68
6 599.96 210.72
7 624.96 210.62
8 644.80 225.83
9 650.22 235.00
***
1.651
* * *
Failure Surface Specified By 7 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 493.33 210.38
2 516.46 200.88
3 541.27 203.95
4 566.26 204.43
5 588.30 216.22
6 611.78 224.82
7 614.40 227.88
* * *
1.662
***
Failure Surface Specified By 9 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 485.56 209.27
2 504.40 192.85
3 527.42 183.10
4 551.97, 187.82
5 576.49 192.74
6 599.22 203.14
7 621.36 214.74
8 642.15 228.63
9 654.01 235.00
***
1.687
***
Y A X I S F T
.00 86.25 172.50 258.75 345.00 431.25
X .00 + +-W* + + + +
86.25 +
A 172.50 +
X 258.75 +
345.00 +
W*
W
*
W
S 431.25 +
517.50 +
*
4
*
. 1247
...3 *
.6124*
.6054.
132.
...60152
....3*9*
F 603.75 + ..6.142
- ....319.
..6.3..
...6.1*
. ....61
T 690.00 + W
1
** PCSTABL5M **
by
Purdue University
--Slope Stability Analysis --
Simplified Janbu, Simplified Bishop
or Spencer°s Method of Slices
Run Date:
Time of Run:
Run By:
Input Data Filename:
Output Filename:
Plotted Output Filename:
pls
1041add.in
1041add.out.
1041add.plt
•
PROBLEM DESCRIPTION Static Analysis of lower Lacy slope
BOUNDARY COORDINATES
4 Top Boundaries
5 Total Boundaries
Boundary X -Left Y -Left X -Right Y -Right
No. (ft) (ft) (ft) (ft)
1 .00 , 135.00 20.00 135.00
2 20.00 135.00 250.00 195.50
3 250.00 195.50 325.00 215.00
4 325.00 215.00 440.00 223.00
5 250.00 195.50 440.00 207.00
ISOTROPIC' SOIL PARAMETERS
2 Type(s) of Soil
Soil Total Saturated Cohesion
Type Unit Wt. Unit Wt. Intercept
No. (pcf) (pcf) (psf)
1 124.0 124.0
2 120.0 120.0
Friction
Angle
(deg)
Pore
Pressure
Param.
.0 25.0 .00
.0 30.0 .00
1 PIEZOMETRIC SURFACE(S) HAVE BEEN SPECIFIED
Soil Type
Below Bnd
1
1
2
2
1
Pressure Piez.
Constant Surface
(psf) No.
.0 0
.0 0
1
Unit Weight of Water = 62.40
Piezometric Surface No. 1 Specified by 3 Coordinate Points
Point X -Water Y -Water
No. (ft) (ft)
1 20.00 135.00
2 220.00 145.00
3 440.00 170.00
Searching Routine Will Be Limited To An Area Defined By 1 Boundaries
Of Which The First 0 Boundaries Will Deflect Surfaces Upward
Boundary X -Left Y -Left X -Right Y -Right
No. (ft) (ft) (ft) (ft)
1 .00 100.00 440.00 100.00
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Circular Surfaces, Has Been Specified.
500 Trial Surfaces Have Been Generated.
50 Surfaces Initiate From Each Of 10 Points Equally Spaced
Along The Ground Surface Between X = 10.00 ft.
and X = 200.00 ft.
Each Surface Terminates Between X = 240.00 ft.
and X = 440.00 ft.
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y =100.00 ft.
10.00 ft. Line Segments Define Each Trial Failure Surface.
Restrictions Have Been Imposed Upon The Angle Of Initiation.
The Angle Has Been Restricted Between The Angles Of -45.0
And 5.0 deg.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Examined. They Are Ordered - Most Critical
First.
* * Safety Factors Are Calculated By The Modified Bishop Method * *
Failure Surface Specified By 8 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 178.89 176.79
2 188.86 177.59
3 198.75 179.03
4 208.54 181.09
5 218.17 183.78
6 227.61 187.08
7 236.82 190.97
8 241.28 193.21
Circle Center At X = 171.7 ; Y = 331.1 and Radius, 154.5
*** 1.807 ***
Individual data on the 7 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Slice Width Weight Top Bot Norm Tan Hor Ver Load
No. Ft(m) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg) Lbs(kg)
1 010.0 1127.0 .0 .0 .0 .0 .0 .0 .0
2 9.9 2954.8 .0 .0 .0 .0 .0 .0 .0
3 9.8 3938.6 .0 .0 .0 .0 .0 .0 .0
4 9.6 4089.3 .0 .0 .0 .0 .0 .0 .0
5 9.4 3441.1 .0 .0 .0 .0 .0 .0 .0
6 9.2 2050.7 .0 .0 .0 .0 .0 .0 .0
7 4.5 292.7 .0 .0 .0 .0 .0 ,.0 .0
Failure Surface Specified By 15 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 115.56 160.14
2 125.55 160.59
3 135.51 161.38
4 145.45 162.49
5 155.35 163.93
6 165.19 165.70
7 174.97 167.80
8 184.67 170.21
9 194.29 172.95
10 203.81 176.01
11 213.23 , 179.37
12 222.53 183.05
13 231.70 187.03
14 240.74 191.32
15 247.65 194.88
Circle Center At X = 106.8 ; Y = 462.1 and Radius, 302.1
***
1.813
* * *
Failure Surface Specified By 16 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 115.56 160.14
2 125.55 160.47
3 135.53 161.13
4 145.48 162.11
5 155.40 163.40
6 165.27 165.01
7 175.08 166.94
8 184.83 169.18
9 194.50 171.73
10 204.08 174.58
11 213.57 177.74
12 222.95 181.20
13 232.21 184.97
14 241.35 189.02
15 250.36 193.37
16 258.85 197.80
Circle Center At X = 110.0 ; Y = 472.8 and Radius, 312.7
***
1.818 ***
Failure Surface Specified By 11 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 178.89 176.79
2 188.87 177.47
3 198.80 178.60
4- 208.68 180.19
5 218.47 182.23
6 228.15 184.72
7 237.71 187.65
8 247.12 191.03
9 256.37 194.83.
10 265.44 199.05
11 267.18 199.97
Circle Center At X = 169.3 ; Y = 393.4 and Radius, 216.8
*** 1.822 ***
Failure Surface Specified By 19 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 115.56 160.14
2 125.55 160.58
3 135.52 161.29
4 145.47 162.26
5 155.40 163.50
6 165.28 165.00
7 175.13 166.75
8 184.92 168.77
9 194.66 171.04
10 204.34 173.57
11 213.94 176.36
12 223.47 179.40
13 232.91 182.68
14 242.27 186.22
15 251.52 190.00
16 260.68 194.03
17 269.72 198.29
18 278.65 202.79
19 279.22 203.10
Circle Center At X = 103.6 ; Y 538.8 and Radius, 378.9
***
1.823 ***
Failure Surface Specified By 29 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 31.11 137.92
2 41.11 138.20
3 51.10 138.65
4 61.08 139.27
5 71.05 140.06
1
6 81.00 141.02
7 90.94 142.15
8 100.85 143.46
9 110.74 144.93
10 120.61 146.57
11 130.44 148.38
12 140.24 150.36
13 150.01 152.51
14 159.74 154.83
15 169.42 157.31
16 179.07 159.96
17 188.66 162.77
18 198.21 165.75
19 207.71 168.89
20 217.14 172.19
21 226.52 175.65
22 235.84 179.28
23 245.10 183.06
24 254.29 187.00
25 263.41 191.10
26 272.46 195.36
27 281.44 199.77
28 290.33 204.33
29 296.35 207.55
Circle Center At X = 20.0 ; Y 720.5 and Radius, 582.7
*** 1.827 ***
Failure Surface Specified By 31 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 31.11 137.92
2 41.10 138.37
3 51.08 138.95
4 61.06 139.69
5 71.02 140.57
6 80.97 141.60
7 90.90 142.78
8 100.81 144.10
9 110.70 145.56
10 120.57 '147.18
11 130.41 148.93
12 140.23 150.83
13 150.02 152.88
14 159.78 155.07
15 169.50 157.40
16 179.19 159.88
17 188.84 162.49
18 198.45 165.25
19 208.02 168.15
20 . 217.55 171.19
21 227.03 174.37
22 236.46 177.69
23 245.85 181.15
24 255.18 184.75
25 264.46 188.48
26 273.68 192.35
27 282.84 196.35
28 291.95 200.49
29 300.99 204.76
30 309.97 209.16
31 317.72 213.11
Circle Center At X = 6.0 ; Y = 817.5 and Radius, 680.0
***
1.830 ***
Failure Surface Specified By 26 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 10.00 135.00
2 20.00 134.70
3 30.00 134.63
4 39.99 134.80
5 49.99 135.20
6 59.97 135.84
7 ' 69.93 136.72
8 79.86 137.83
9 89.77 139.18
10 99.65 140.76
11 109.48 142.57
12 119.27 144.62
13 129.01 146.89
14 138.69 149.40
15 148.31 152.13
16 157.86 155.09
17 167.34 158.28
18 176.74 161.68
19 186.06 165.31
20 195.29 169.16
21 204.42 173.23
22 213.46 177.51
23 222.40 182.00
24 231.22 186.71
25 239.93 191.62
26 243.65 193.83
Circle Center At X = 27.9 ; Y = 557.3 and Radius, 422.7
*** 1.834 ***
Failure Surface Specified By 12 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 157.78 171.24
2 167.78 171.25
3 177.76 171.79
4 187.70 172.88
5 197.57 174.51
6 207.33 176.68
7 216.96 179.37
8 226.43 182.59
9 235.71 186.31
10 244.78 , 190.53
11 253.60 , 195.24
12 257.04 197.33
Circle Center At X = 162.8 ; Y = 354.0 and Radius, 182.9
*** 1.837 ***
Failure Surface Specified By 21 Coordinate Points
Point X -Surf Y -Surf
No. (ft) (ft)
1 115.56 160.14
2 125.54 160.69
3 135.51 161.46
4 145.46 162.44
5 155.39 163.64
6 165.29 165.05
7 175.16 166.68
8 184.99 168.52
9 194.77 170.57
10 .204.52 172.83
11 214.21 175.29
12 223.84 177.97
13 233.42 180.85
14 242.93 183.94
15 252.37 187.24
16 261.74 190.73
17 271.03 194.43
18 280.24 198.33
19 289.36 202.42
20 298.40 206.71
'21 304.07 209.56
Circle-.Can.ter. �A;tt.X =.. -94.8 ; Y = 623.8 and Radius, 464.1
:4r
***
Y
1.838 ***
A X I S F T
.00 55.00 110.00 165.00 220.00 275.00
X .00 +, + L-+----*----+ + +
8
8*
..86
..8
55.00 + 6
6
67.
86.
86..
6
A 110.00 + 6
86.2
6 2
6 2
632
6 29
X 165.00 + 629
832
6821
621
6821
631
I 220.00 + W 601
651
7631
6 2*
643
764.
S 275.00 + 765
6
766
70
7
330.00 +
F 385.00 +
*
J•
T 440.00 + COCtL W *..*
r•
-._.---IC __ •-NI � \ \ - 1
Ile _ n1(, x.tt0.:n \ - ..
i[ "lavPlt azoi• c. amanf z___;
v.m � - - ( 'r (40
1151rrotk- Ion. CfiP _ - �t _ �, I d! - QrlvntntRI ���.' -Mr q-ti;l5•.. •tt•.
lE fl+';t L cllt
ri er tln,g }J��L. phi IR!_vatm---i 1 - i 1•'gA Phi III:I lIIA -I„i'+t°
If Ili Awl% iV.Ir ' I Jl�l. CI I..• ��` f�. K_ r ICS., •
•• r+dDA �%l'I Dry qG two / 1513
P,P• 51:1 nt t i1. ^I`O +11.4t i I' , .4 •.
'a ICS
I:, 5`V.,0 • _',ill 41'C.y1 •-•r -)��
tU1L mr(trml Aro)
SANITARY SEWER EXTENSION
SUMO SW 1/4 OF THE SW 1/4OF SEC. 23. T1VP. 231.1, R. 4E. W.M.
neer
RODGERUn
325 SO. OARMA
$AmL WA 9808
SCALE: HORIZONTAL 1' = 30', VERTICAL 1' = 10'
260 210
220 170.
July 24, 1995
•
City of Tukwila
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
Mr. Rodger Lacy
4133 46th Avenue S.
Seattle, WA 98188
Re: Lacey Project, E95-0010: S. 158th Right -of -Way Use.
Dear Mr. Lacey:
Per our telephone conversation on 7/21/95, I want to repeat my response to you concerning
the use of the S. 158th ROW and wetlands existing therein. Your plan to construct sanitary
sewer and water lines ect., and the driveway access to the future home site should be
accomplished at the same time. You may also want to consult Public Works regarding any
stormwater/drainage improvements that may need to be located within the ROW.
The wetlands that exist within the City's ROW east of the 51st Avenue S. culdesac are
shown as delineated by Watershed Dynamics. These flagged locations (Al thru A6) show
the eastern edge of wetlands in that area. Please include their locations on the map you
submit to Public Works for your Utility Permit. They will route it to me for comments.
Even though your past clearing activities have likely removed those wetland flags, any
impacts to wetlands in the ROW will need to be restored as part of the Utility Permit
application.
After you submit your application, I may need to visit the site but will contact you prior to
that time. If you have questions, please contact me at 431-3662.
Sincerely,
C. Gary Sclz
Urban Environmentalist
cc: Steve Lancaster, DCD Director
Libby Hudson, Associate Planner
Joanna Spencer, PW Development Engineer
6300 Southcenter Boulevard, Suite #100 e Tukwila, Washington 98188 a (206) 431-3670 • Fax (206) 431-3665
City of Tukwila
6200 Southcenter Boulevard • Tukwila, Washington 98188 John W Rants, Mayor
July 13, 1995
Roger Lacey
3125 S Dakota St.
Seattle, WA 98101
Re: S 158 St. Right -of -Way and Soils Review
Dear Mr. Lacey,
Thank you for meeting to discuss your plans to construct a new home in Tukwila. The area that
you will be using has had a history of soils and drainage problems so the reviews and approvals
need to consider those known conditions.
The Geotechnical Soils Report that you submitted has been reviewed by Shannon and Wilson for
us. Shannon and Wilson was complimentary in saying that it was a thorough report. The
Geotechnical Engineers are concluding some details for the report and permits.
We have contacted WSDOT on turning back the triangle area of limited access affecting the S
158 St. right-of-way. WSDOT has contacted their Olympia Headquarters and has explained to
us that the turnback documents will be prepared and sent to the City for acceptance. Council �.
approval is required and thiswill be scheduled for the Transportation Committee and Council
when the WSDOT documents are received.
Your patience in permit approvals is appreciated. We've experienced substantial soils and
drainage problems in constructing Crystal Springs Park, S 158 St. & 51 Ave S, and S 160 St.
improvements. I'm sure that you understand the care that needs to be taken for the approvals
considering that experience.
Sincerely,/') f
ohn W. Rants
Mayor
JWR/so
cf: Dept of Community Development
Public Works Dept
City Attorney
Phone: (206) 433-1800 • City Hall Fax: (206) 433-1833
July 5, 1995
41
City of Tukwila
John W. Rants, Mayor
Department of Public Works Ross A. Earnst, P. E., Director
Mr. Rodger E. Lacy, Sr.
3125 Dakota Street
Seattle, Washington 98108
RE: Lacy Project, L95-001, E95-0010
Dear Mr. Lacy:
RECEwED
199;
Culvciviuvs r y
DF_VELOPMFNT
You called Wednesday, July 5, 1995 inquiring about the Shannon and Wilson peer review of Galli's geotechnical report and
requesting a copy of the Crystal Springs mapping showing the fence line. The Shannon and Wilson report is attached.
Page 5 identifies four areas where additional information is needed
1. The top (first) paragraph requests the supporting data, assumptions and calculations used in deriving the factors of
safety.
2. The second paragraph requests a seismic stability analysis and the assumptions and calculations be provided.
3. Explanation of why remedial section C is not applicable and why the inclined bedding plane orientation in Remedial
Sections D and E is considered to provide greater sloping stability than other bedding orientations.
4. Estimates of site specific groundwater and surface water discharge estimates, for retention system design.
Please return this information to Development Engineer, Joanna Spencer.
The Construction Engineer returns from vacation next week. Upon his return, the Crystal Springs drawings will be
forwarded to you.
As explained in previous conversations, this area has a significant history of geotechnical problems. We've experienced
them with the park construction, and street construction. They continue to remind us of the need for extreme care.
Sincerely,
Ron M. Cameron, P.E.
City Engineer
RMC/cd
enclosure: June 26, 1995 Shannon and Wilson report
cf: Steve Lancaster, DCD Director
Joanna Spencer, Development Engineer
ronlacy.doc
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • Phone: (206) 433-0179 • Fax (206) 431-3665
DRAFT
June 30, 1995
Mr. Rodger E. Lacy Sr.
3125 S. Dakota Street
Seattle, WA 98108
RE: Lacy project, L95-001, E95-0010
Dear Mr. Lacy:
This letter is to update you on the status of your project since our meeting of June 15, 1995. First, let
me go over what has been accomplished in reference to the project.
You purchased property with wetlands and slopes with instability history, so the property is
significantly impacted by the City of Tukwila's Sensitive Areas Ordinance (SAO). Your intentions to
develop a single family residence on the property are significantly limited by the SAO. In meeting with
City staff, you were informed that an exception from the ordinance may be possible due to the
constraints on the property, so you applied for a reasonable use exception as described in the TMC
18.45.115.
To obtain the exception you have submitted numerous plans and a geotechnical report. On April 27,
1995, the Planning Commission granted you a reasonable use exception (with four conditions) from
the Sensitive Areas Ordinance. This exception grants you conditional permission to develop a single
family use within a sensitive area of Tukwila Please note that a use permitted through a reasonable
use exception must also conform to the procedures of the sensitive areas overlay zone and be
consistent with the underlying R1-7.2 zoning regulations [TMC 18.45.080(h)].
You have also submitted for SEPA environmental review to construct a single family residence on
lands covered by water [WAC 197-11-800(b)]. The SEPA checklist remains under review pending a
peer review of the geotechnical report you submitted. We received the peer review report yesterday
and the Public Works Department is continuing review of the report. The report brings up questions
regarding stability of the subject property. I have attached a copy of the report for your information.
Due to the complexity of this site, there are a number of issues that need to be resolved before the
environmental review can be completed, and before building permit applications are submitted, or any
work can begin on the site.
1. Stability Issues
2. Survey Issues Regarding the South Property Line
It has been brought to my attention that the survey for your property appears to be incorrect.
Your survey indicates that the fence line for Crystal Springs Park is located within the 60 foot
right-of-way for unimproved S. 158th Street, when according to the Public Works Department,
this fence line is located along the park boundary and not within the right-of-way. This
discrepancy alters your south property line, building location and wetland enhancement plan.
Please have your surveyor check the survey and provide documentation that indicates where
the south property line lies in respect to the public right-of-way for S. 158th Street.
3. Site Clearing Without Permit Approval
Mechanical site clearing has occurred on the site without required permits or an approved
wetland enhancement plan. This type of clearing was expressly denied by the city staff.
Please be aware that any damage to wetland areas will be required to be remedied with the
final wetland enhancement plan.
4. Wetland Enhancement
Due to the stability issues related to the on-site drainage which have been raised in the peer
review, the final wetland enhancement plan may need to provide off-site enhancement. The
plan will need to go back before the Planning Commission if it is significantly altered from the
approved conceptional wetland enhancement plan. The final enhancement plan (including
on and off-site enhancement) needs to be approved by the Director of Department of
Community Development (DCD) and to conform to the sensitive areas overlay zone
regulations and conditions of the reasonable use exception. Options for wetland
enhancement need to be discussed with your technical people and our urban
environmentalist.
5. Access
The Fire Department access requirement and the access to the site needs to be resolved. I
understand that you have not given up on the possibility that Washington State Department of
Transportation (WSDOT) may grant you permission to use the adjacent property for access.
However, if you access the property by way of the unimproved right-of-way for S. 158th Street,
the Public Works Department will need to see grading plans for this proposal, and any
necessary retaining walls necessary.
6. Building Permit Application
As part of the normal requirements for a single family residential building permit, you will need
to submit a final site plan showing all impacted wetland areas, the building location, all paved
access areas, any required fire truck turnaround areas, utility easements, any existing
easements (eg. on-site well). You will also be required to submit a grading plan showing
existing and proposed grades, and final on-site wetland enhancement, a storm drainage plan
with storm drainage calculations. In addition, Public Works will require that you submit plans
for all necessary utility extensions and connections.
7. Issues Raised During the June 15th Meeting
Watercourses - You questioned whether the channelled water on your property were
misinterpreted and should not be considered watercourses and subject to the sensitive areas
ordinance. The definition of a watercourse is °a course or route formed by nature or modified
by man, generally consisting of channel with a bed and banks or sides substantially
throughout its length along which surface water flows naturally other than the
Green/Duwamish River. The channel or bed need not contain water year-round. Water
courses do not include irrigation ditches, stormwater runoff channels or devices, or other
entirely artificial watercourses unless they are used by salmonids or to convey or pass through
stream flows naturally occuring prior to construction of such devises.° (TMC 18.06.935)
The source of the water on your property is from natural seepage. Although the streams may
have been altered by to channel the natural seepage, the on-site streams clearly fit the
definition of a watercourse and are therefore subject to the sensitive areas ordinance.
Wetland enhancement - You asked if you could alter your conceptional enhancement plan
and place wetland enhancement west of the building pad. This issue needs to be discussed
as part of the revised enhancement plan.
Building Pad Location - You said that your understanding of reducing the impact area meant
that you needed to add a toe wall only as suggested by your geotechnical engineer. After
reviewing the minutes from the hearing, it is clear that the Planning Commissions intention was
to reduce the area of the building pad by adding a toe wall and other means that the
geotechnical engineer and the city staff could agree upon. The Commission said that the
details should be worked out with the technical people and the city staff.
Driveway Pavement - City policy is to require that residential driveways be paved.
We should discuss these items and the geotechnical peer review report further at a meeting with your
technical people. I will call to arrange a meeting for the week of July 10 through July 14th, at your
convenience.
If you have any questions regarding the status of your project please contact me at 431-3670. I will
make every attempt to assist you in moving your project forward.
Sincerely,
Jack Pace
Senior Planner
attachments
C: Steve Lancaster
Ron Cameron
Joanna Spencer
Gary Schulz
Libby Hudson
LACY.L30
•
City of Tukwila la John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
June 30, 1995
Mr. Rodger E. Lacy Sr.
3125 Dakota Street
Seattle, WA 98108
RE: Lacy project, L95-001, E95-0010
Dear Mr. Lacy: ,
In response to our telephone conversation this morning, I would like to provide some
clarification on several items. This letter is not intended to address all remaining issues
related to your project, but only to address your concerns about the location and size of
your home. We will provide a more detailed analysis of all remaining issues once the
geotechnical _peer review is completed.
First, I agree with you that the Planning Commission's decision on your Reasonable Use
Exception authorizes construction of your proposed home at the location you have
proposed, subject to specific conditions relating to reduction of the area of impact,
appropriate site development measures, and mitigation of wetland impacts through
enhancement. The only circumstances under which the home would have to be
relocated is if it is determined that construction cannot safely occur at that location from
a geotechnical perspective, or if a new, survey affects your site plan. As you know, the
City is currently conducting peer review of your consultant's geotechnical report. I
expect to have the results of that review within the next week or two.
Second, the Department of Community Development will not require a reduction in the
size of your proposed home.
Third, let me remind you that prior to issuance of building permits, you must submit a
plan that demonstrates how you will provide appropriate wetland impact mitigation, at an
enhancement ratio of 1.5 to 1. This plan must meet the intent of the City's Sensitive
Areas Ordinance, will be subject to my approval, and must be carried out prior to the
issuance of a building permit. This plan must also remedy any damage done to
wetlands on your property due to the unauthorized mechanical site clearing that
occurred several weeks ago.
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 6 (206) 431-3670 • Fax /2061431-3665
Mr. Rodger E. Lacy
June 30, 1995
Page 2 of 2
Please contact me at 431-3670 if you would like to discuss these matters further.
Sincerely,
Steve Lancaster, Director
Department of Community Development
cc: Ron Cameron, City Engineer
Jack Pace, Senior Planner
Gary Schulz, Urban Environmentalist
`Libb:y Hudson, Associate Planner i
CITY OF rI.wrcn
6200 Soutncenter Boulevard, Tukwila, Washington• 98188
(206) 433-1800
.o. L i\-3\0
FROM:
DATE• &) 2 8 L
SUBJECT: `' W o &11 e f o al' a_ia 1 -e -S e..,%1
\le c� vt-\- C9 4b A a/ 1 S ciWot c\Qc1
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ov. s\oee `1-4\ \; -_/ I ssves Ac'a;,nale .cam,\A bass
'Fur 'co 10 e -D
MEMORANDUM
•
J11 SHANNON 6W1LsoN, INC • SEATTLE
FHANFORD
AIRBANKS
GEOTECHNICAL AND ENVIRONMENTAL CONSULTANTS ANCHORAGE
SAINT LOUIS
BOSTON
June 26, 1995
City of Tukwila
Department of Public Works
6300 Southcenter Boulevard, Suite 100
Tukwila, Washington 98188
Attn: Mr. Ron Cameron, City Engineer
RECEIVED
JUN 2 8 1995
PUBLIC WORKS
RE: GEOTECHNICAL REVIEW OF PROPOSED SINGLE-FAMILY RESIDENCE
DEVELOPMENT, 51ST AVENUE SOUTH, TUKWILA, WASHINGTON
This letter presents the results of our review of the proposed Roger E. Lacy, Sr. residence,
Tract 48 of Sunnydale Gardens, Division 1, in the vicinity of the 51st Avenue cul-de-sac,
Tukwila. In accordance with your request, we have conducted a geotechnical review of the
suitability of this property for development of a single-family residence. Specifically, we
have attempted to address the following issues identified in your letter of May 18, 1995:
► Is the property affected by the same deep slide plane as the proposed Hillcrest
Development (located to the southwest along Slade Way)?
► Are there any geological concerns for a house on the Lacy property?
► Are there any drainage concerns to address, and specifically, is the plan sufficient
relative to the adjacent Washington State Department of Transportation (WSDOrT)
system?
For this review, you provided us with a geotechnical report for the subject property dated
March 15, 1995, prepared by the Galli Group, as well as copies of several reports and
supporting documents pertaining to the Hillcrest Development.
SCOPE OF WORK
The scope of our services consisted of a site visit and visual reconnaissance of the Lacy
property by Mr. Dan Clayton on June 19, 1995; review of a geotechnical report that was
prepared for the subject property by the Galli Group in March 1995; and review of Shannon
400 NORTH 34TH STREET • SUITE 100
P.O. BOX 300303
SEATTLE, WASHINGTON 98103
206.632.8020 FAX 206.633.6777
TDD: 1.800.833.6388
W-7039-01
•
City of Tukwila
Attn: Mr. Ron Cameron
June 26, 1995
Page 2
?HANNON &WILSON, INC.
& Wilson files pertaining to geotechnical investigations of the area that were performed for
WSDOT during the 1960's. The reports and supporting documents for the Hillcrest
Development were briefly reviewed, but are not considered directly relevant to the geologic
conditions at the Lacy property.
SITE CONDITIONS
The Lacy property is located immediately north of Crystal Springs Park and west of the cul-
de-sac at the end of 51st Avenue South, Tukwila, Washington. The property is situated
approximately half way up the moderately steep northeast -facing slope of the Duwamish
Valley to the southwest of the Tukwila freeway interchange. It is an elongate plot,
approximately 150 by 600 feet in dimension, bounded on the south by Crystal Springs Park,
and on the north, west, and east by undeveloped land. The site is currently undeveloped,
artially cleared and partially covered withblackberry bushes, alder trees and a few maple
S,ome-_ofcthe clearing`app`earrtorhavebeenaccomplished veryZ:recently; as there /asl
Ao0v_egetationagrowing on.what-appeared;to�be freshly soil atil eetiinesf our visit.
e property has a total of over 70 feet of relief, with a steep slope on the western end of
e site and a moderate slope extending from • the base of the steep slope to the eastern end
of the property. At the time of our site visit, there was a considerable"amount::ofr: surface
fflo i g ac the, site, te, mostly along shallow ditches that have been constructed to
provide site drainage. Some of these ditches flow into a larger ditch constructed along the
northern property boundary, and all appear to flow ultimately to an asphalt -lined ditch near
• the eastern end of the site. tGThis surface..wateraifderived.-laigely-.from: seepage at or near
the base of the steep slope near the western end of the property, although * some. surface
waterrobably flows_. ontoAhe, site from. further:_upslope; 'especially' during= the.rainy. season.
The upper, western half of the site is underlain at the surface by loose sand that appears to
be old landslide deposits or colluvium derived from the steep slope on the western end of
the site. Fill materials consisting primarily of sand and silty sand cover much of the lower,
eastern half of the site. The natural surficial soils in this area include both sand and clayey
silt. According to the geotechnical report, the owner wishes to build on the lower, eastern
part of the site in an area that is partially mantled by old fill materials.
W-7039-01
City of Tukwila
Attn: Mr. Ron Cameron
June 26, 1995
Page 3
•
SHANNON &WILSON. INC.
The steep slope that crosses the western end of the property is interpreted as the headscarp
of an ancient landslide, with all of the material to the east of it occupying the downdropped
block of the slide. There have been numerous smaller landslides within this ancient
landslide mass, many of which were associated with the construction of the Tukwila
Interchange at the foot of the hill during the 1960's. Most of these smaller slides were
remediated by WSDOT in the mid -1960's as part of an extensive hillside stabilization
program. No evidence of recent sliding was observed on or adjacent to the site during our
reconnaissance.
DISCUSSION
The geotechnical report prepared by the Galli Group is based on a site reconnaissance;
excavation of five test pits in the area where the residence is proposed to be constructed;
and a review and evaluation of subsurface information, geotechnical evaluations, and
remedial measures implemented by WSDOrr approximately 30 years ago as part of an
extensive program to stabilize the hillside above the Tukwila Interchange and Interstate
Highway 5 . The report provides recommendations for slope stability, foundation design,
grading and earthwork, and site drainage, based on the proposed construction of a two-
story, wood -frame, single-family residence on the eastern half of the property.
It is our opinion that the Galli Group report generally provides appropriate geotechnical
recommendations for measures that will be required to successfully develop this property.
However, with respect to their evaluation of slope stability, the report appears to rely
heavily on evaluations that were performed thirty years ago for a somewhat different
purpose. Unfortunately, the Galli Group report does not provide the dat-a-and assumptions_
• that were used in developing their conclusions regarding slope stability, so it is not possible
to provide an independent evaluation of the applicability of those slope stability evaluations
to present-day site conditions. Moreover, it is not clear from their report whether the Galli
Group accepted the factors of safety, for, slope stability provided by the 1964.:Shannon
Wilson report, or whether they re-evaluated the data, assumptions,, and calculations used in
establishing those conclusions based on present-day conditions for the purpose of this
development. In our opinion, such a re-evaluation would be appropriate, considering the
potential for changed conditions over the intervening 30 years.
W-7039-01
City of TLkwila
Attn: Mr. Ron Cameron
June 26, 1995
Page 4
SHANNON &WILSON. INC.
Perhaps as a result of the lack of supporting data for the stability analyses, there are. also.a.
few apparent discrepancies or. omissions in the Galli Group's report with respect to their
conclusions. about the hillside stability. In particular, it is not clear (a) why the inclined
bedding shown in Remedial Sections D and E (Figures 3A and 3B) is considered to enhance
the slope stability of this area, (ti) why a dewatering system would have been installed in
the first place if the factor of safety without it was 1.9, and (c) why Remedial Section C
should not also be considered in assessing the stability of the eastern part of the site.
With respect to drainage provisions, the Galli Group report states that adequate drainage
will be a critical factor in the preparation of the site for construction and will help to
increase the local and global stability of the hillside. Accordingly, they provided
recommendations for placement and construction of drainage measures, apparently including
a storm water retention/detention system. However, little is actually said about the storm
water retention system design other than a recommendation that it be a closed system (not
surface ponding) to reduce the likelihood of a cataclysmic discharge of water to the hillside.
There is no mention which, if any, of the site drainage systems will be tied into the storm
water retention/detention system and how that system will be sized to acommodate: peak:
fiows,from_groundwater. and., surface..water. We believe that this will be an important
design consideration that will have to be addressed in order to comply with WSDO2's
prohibition ofincreasing. peak;discharge: to.. their; hillside -drainage system.
FINDINGS AND RECOMMENDATIONS
In general, the geotechnical investigation that has been performed and the recommendations
that have been provided for the Lacy property appear to be adequate and appropriate for the
type of development that is proposed. The largest single concern for the property is slope
stability because it lies within an extensive ancient landslide mass that has been subjected to
subsequent, relatively small movements on the slope below the site. Based on the lack of
recent slide movements and an evaluation of slope stability, the owner's geotechnical
consultant concluded that the hillside has apparently been stabilized by WSDOT remedial
measures that were implemented in the mid -1960's. Specifically, they concluded that, for
the most probable mode of shallow and progressive failure, the slopes below the site have
been effectively stabilized (by remedial measures performed about 30 years ago).
W-7039-01
City of Tukwila
Attn: Mr. Ron Cameron
June 26, 1995
Page 5
• NNON&WILSON. INC.
Based on their evaluation, the Galli Group provided factors of safety for static conditions
for the site that are generally considered adequate for residential development. Although
their findings appear to be reasonable, the supporting data, assumptions, and calculations
used in deriving the factors of safety are not included in their report. It is our opinion that
the data, assumptions, evaluations, and calculations used in deriving the factors of safety
should be provided to the City for their review before issuing a permit for the property
development.
The Galli Group concluded thatYdynatn cloading need not be considered in evaluating the
stability of the proposed development, and apparently, based this -conclusion on a statement
made in a 1964 Shannon & Wilson report for WSDOT. Considering the increased concern
for seismicity in the Puget Sound region that has developed since 1964 and the location of
this site in an area that has loose soils and landslide potential, we believe that a `seismic.
st``a__bility,analysis\shoulddbe;performed for:.,the property and that the assumptions and
44,0calculations used in this analysis should be provided for the City's review..
*
_ Along with the supporting information for stability analyses, the owner's geotechnical
consultant should explain why Remedial Section C (shown in Figure 3 of the Galli report) is
not applicable to the eastern part of the site, and why the inclined bedding plane orientation
shown in Remedial Sections D and E (Figures 3A and 3B) is considered to provide greater
slope stability than other bedding orientations. This is particularly true if this bedding
orientation has been used in the assumptions for their stability analyses.
Apart from potential slope stability issues, there do not appear to be any significant geologic
constraints or drainage issues that could not be addressed in the geotechnical design and
development of the site. ;However; site-specific groundwater and surface -water discharge
estimateswill,beTnecessary, to_size an appropriate stormwater. retention system- capable of
retaining the peak storm water runoff once the basic building design has been established.
In our opinion, the timing for submittal of this information is not critical as long as the
owner is aware of the design requirements that will be needed to address WSDOT-imposed
peak discharge restrictions.
W-7039-01
City of Tukwila • PiANNON iWILSON. INC.
Attn: Mr. Ron Cameron
June 26, 1995
Page 6
LIMITATIONS
This letter report has been prepared for the City of Tukwila in accordance with generally
accepted professional engineering principles and practices, for use by the City of Tukwila in
review of the proposed Lacy single-family residential development at 51st Avenue South,
Tukwila. No other warranty, either expressed or implied, is made as to the nature of the
conclusions and recommendations. The content of this report is not intended for the use of
other parties or for other purposes. It may or may not contain sufficient information for
other uses. Shannon & Wilson, Inc. has prepared the attached "Important Information
About Your Geotechnical Report" to assist you and others in understanding the use and
limitations of our reports.
We appreciate the opportunity to be of service.
Sincerely,
SHANNON & WILSON, INC.
Daniel N. Clayton, R.G., C.E.G.
Senior Associate
DNC:WPG/dnc
Enclosures: Important Information About Your Geotechnical Report
EXPIRES 11/10/ 94
W. Paul Grant, P.E.
Vice President
W7039-01.LT1 /W7039-1kd/eet
W-7039-01
armSHANNON & WIL, INC. AttachmelReport W-7039-01 Page 1 of 2
III
Geotechnical and Environmental Consultants Dated: June 26, 1995
Tb: City of Tukwila
Attn: Mr. Ron Cameron
Important Information About Your Geotechnical/Environmental Report
CONSULTING SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES AND FOR SPECIFIC CLIENTS.
Consultants prepare reports to meet the specific needs of specific individuals A report prepared for a civil engineer may not be
adequate for a construction contractor or even another civil engineer. Unless indicated otherwise, your consultant prepared your
report expressly for you and expressly for the purposes you indicated. No one other than you should apply this report for its
intended purpose without first conferring with the consultant. No party should apply this report for any purpose other than that
originally contemplated without first conferring with the consultant.
THE CONSULTANT'S REPORT IS BASED ON PROJECT -SPECIFIC FACTORS.
A geotechnical/environmental report is based on a subsurface exploration plan designed to consider a unique set of project -
specific factors. Depending on the project, these may include: the general nature of the structure and property involved; its size
and configuration; its historical use and practice; the location of the structure on the site and its orientation; other improvements
such as access roads, parking lots, and underground utilities; and the additional risk created by scope -of -service limitations
imposed by the client. To help avoid costly problems, ask the consultant to evaluate how any factors that change subsequent to
the date of the report may affect the recommendations. Unless your consultant indicates otherwise, your report should not be
used: (1) when the nature of the proposed project is changed (for example, if an office building will be erected instead of a
parking garage, or if a refrigerated warehouse will be built instead of an unrefrigerated one, or chemicals are discovered on or
near the site); (2) when the size, elevation, or configuration of the proposed project is altered; (3) when the location or orienta-
tion of the proposed project is modified; (4) when there is a change of ownership; or (5) for application to an adjacent site.
Consultants cannot accept responsibility for problems that may occur if they are not consulted after factors which were considered
in the development of the report have changed.
SUBSURFACE CONDITIONS CAN CHANGE.
Subsurface conditions may be affected as a result of natural processes or human activity. Because a geotechnical/environmental
report is based on conditions that existed at the time of subsurface exploration, construction decisions should not be based on a
report whose adequacy may have been affected by time. Ask the consultant to advise if additional tests are desirable before
construction starts; for example, groundwater conditions commonly vary seasonally.
Construction operations at or adjacent to the site and natural events such as floods, earthquakes, or groundwater fluctuations may
also affect subsurface conditions and, thus, the continuing adequacy of a geotechnical/environmental report. The consultant
should be kept apprised of any such events,' and should be consulted to determine if additional tests are necessary.
MOST RECOMMENDATIONS ARE PROFESSIONAL JUDGMENTS.
Site exploration and testing identifies actual surface and subsurface conditions only at those points where samples are taken. The
data were extrapolated by your consultant, who then applied judgment to render an opinion about overall subsurface conditions.
The actual interface between materials may be far more gradual or abrupt than your report indicates Actual conditions in areas
not sampled may differ from those predicted in your report. While nothing can be done to prevent such situations, you and your
consultant can work together to help reduce their impacts. Retaining your consultant to observe subsurface construction opera-
tions can be particularly beneficial in this respect.
•
A REPORT'S CONCLUSIONS ARE PRELIMINARY.
Page 2 of 2
The conclusions contained in your consultant's report are preliminary because they must be based on the assumption that condi-
tions revealed through selective exploratory sampling are indicative of actual conditions throughout a site. Actual subsurface
conditions can be discerned only during earthwork; therefore, you should retain your consultant to observe actual conditions and
to provide conclusions. Only the consultant who prepared the report is fully familiar with the background information needed to
determine whether or not the report's recommendations based on those conclusions are valid and whether or not the contractor is
abiding by applicable recommendations. The consultant who developed your report cannot assume responsibility or liability for
the adequacy of the report's recommendations if another party is retained to observe construction.
THE CONSULTANT'S REPORT IS SUBJECT TO MISINTERPRETATION.
Costly problems can occur when other design professionals develop their plans based on misinterpretation of a geotechnical/envir-
onmental report. To help avoid these problems, the consultant should be retained to work with other project design professionals
to explain relevant geotechnical, geological, hydrogeological, and environmental findings, and to review the adequacy of their
plans and specifications relative to these issues.
BORING LOGS AND/OR MONITORING WELL DATA SHOULD NOT BE SEPARATED FROM THE REPORT.
Final boring logs developed by the consultant are based upon interpretation of field fogs (assembled by site personnel), field test
results, and laboratory and/or office evaluation of field samples and data. Only final boring logs and data are customarily
included in geotechnical/environmental reports. These final logs should not, under any circumstances, be redrawn for inclusion
in architectural or other design drawings, because drafters may commit errors or omissions in the transfer process.
To reduce the likelihood of boring log or monitoring well misinterpretation, contractors should be given ready access to the
complete geotechnical engineering/environmental report prepared or authorized for their use. ' If access is provided only to the
report prepared for you, you should advise contractors of the report's limitations, assuming that a contractor was not one of the
specific persons for whom the report was prepared, and that developing construction cost estimates was not one of the specific
purposes for which it was prepared. While a contractor may gain important knowledge from a report prepared for another party,
the contractor should discuss the report with your consultant and perform the additional or alternative work believed necessary to
obtain the data specifically appropriate for construction cost estimating purposes. Some clients hold the mistaken impression that
simply disclaiming responsibility for the accuracy of subsurface information always insulates them from attendant liability.
Providing the best available information to contractors helps prevent costly construction problems and the adversarial attitudes
that aggravate them to a disproportionate scale.
READ RESPONSIBILITY CLAUSES CLOSELY.
Because geotechnical/environmental engineering is based extensively on judgment and opinion, it is far less exact than other
design disciplines This situation has resulted in wholly unwarranted claims being lodged against consultants. To help prevent
this problem, consultants have developed a number of clauses for use in their contracts, reports and other documents. These
responsibility clauses are not exculpatory clauses designed to transfer the consultant's liabilities to other parties; rather, they are
definitive clauses that identify where the consultant's responsibilities begin and end. Their use helps all parties involved recog-
nize their individual responsibilities and take appropriate action. Some of these definitise clauses are likely to appear in your
report, and you are encouraged to read them closely. Your consultant will be pleased to give full and frank answers to your
questions.
The preceding paragraphs are based on information provided by the
ASFE/Association of Engineering Firms Practicing in the Geosciences, Silver Spring, Maryland
1/95
MEMORANDUM
DATE: MAY 31, 1995
TO: STEVE LANCASTER
FROM: UBBY HUDSON
RE: LACY PROJECT 1 `
Attached is a draft chronology of what has transpired on the Lacy project. There are notes in the file
relating to the meetings and discussions. Not all discussions have been noted, but most have.
The status of the project is as follows:
SEPA is pending. I sent a letter to Mr. Lacy, dated May 11, 1995, regarding the need for additional
information in order to complete the SEPA process. He has since submitted a revised plan (received
May 23) with the fire truck turnaround, and relocating his access to the south end of the lot, not
using the existing road bed. I forwarded a copy to Public Works to include in the peer review of the
geotechnical report. In phone conversations he said that there is no plan to revise his geotechnical
report. He also said that he will be using the Right-of-way os S. 158th for access because he cannot
obtain approval from DOT to use their property. He has not addressed item 2 or 4 of the May 11th
letter.
The peer review for Lacy's geotechnical report has not completed by Shannon and Wilson as of yet.
Once we have received the peer review, Gary and I will get together and discuss the project. We then
plan to contact Mr. Lacy and have a meeting with him to discuss the remaining issues for SEPA and
the project, and to discuss what Mr. Lacy needs to do to move forward with his project.
PHONE LOG
May 31, 1995
Conversation with Mr. Lacy on 5/30/95 3:15pm.
Mr. Lacy called because he heard from Gary that I was trying to reach him. I said yes, I had been. I
said that I was calling him as I said I would to discuss meeting. I told him Gary and I talked and we
agreed that it might be better to meet after we have received the results of the peer review.
Mr. Lacy said that his geotechnical engineer was not going to revise his report, that it was final as it
was submitted. He said that the compromise was reached at the meeting by adding the toe wall and
that was al he was going to do. I said that there is also the need to reduce the developed area and
thus the impacts to the sensitive areas and that was what the Planning Commission had agreed on.
The Planning Commission expected staff and the applicant to come to a compromise during the
remaining process for this proposal. I said that we haven't reached that yet.
The discussion went on to what we were looking for in the peer review. I explained that in addition to
reviewing what was proposed in the report, we asked if there were alternatives that would have a
lesser impact to the sensitive areas. Mr. Lacy said we cannot do that. He said that the other
geotechnical engineer would then be taking on the liability of his property. I put off this discussion
and said we could discuss the issues at the meeting after we have received the results.
The discussion then turned to other items. Mr. Lacy said that he would be accessing the property by
way of the public access for S. 158th street as he was not able to get approval from DOT.
At some point Mr. Lacy started complaining that I had lost my objectivity and that I had made this
project personal. He said that I was treating this development as if it were a commercial development
not a single family residence. I disagreed and explained that I was doing what was required to
administer the SAO, and that it all goes back to what he is doing there, building within a sensitive
areas. I said that the Planning Commission looked at specific criteria to allow development, and that
development was approved, but that there are standards that still need to be met. I am attempting to
follow the criteria and standards of the SAO, by developing his proposed single family residence with
the least amount of impact to the sensitive areas that exists on the property.
We got back to some other issues and he kept pushing the issue that he wasn't required to pave his
private driveway. He said I should talk to the building inspectors. I explained that it was a zoning
code issue not a building requirement. He then again said that I was not being objective, because
other planners would check with someone else before dismissing the possibility that gravel has been
permitted in the past.
He continued on about wanting to remove me as his planner and wanted to know who he should
speak with. I said that was his prerogative, and that he should speak to my supervisor. He then
asked to speak to the director and I attempted to transfer him to Steve Lancaster.
City of Tukwila
John W. Rants, Mayor
Department of Community Development Rick Beeler, Director
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
MEMORANDUM
DATE: May 24, 1995
TO: Steve Lancaster
FROM: Libby Hudson k
RE: Lacy environmental review, File #E95-0010
Attached is a revised plan of the Lacy project. Mr. Lacy has addeda fire truck turn around as
required by the fire department. I would like to express my dismay in this requirement. Here we are
asking Mr. Lacy to reduce the impact to the existing sensitive lands, while on the other hand requiring
a significant impact in order for a large emergency vehicles to leave the site after an emergency. The
requirement for one single family residence within a sensitive area seems excessive. The size of the
turn around seems excess. In addition, the access roadway has been moved from the historic
roadbed where the fill area already exists, so that the new configuration can be accommodated. This
change results in more impact to the site.
I heard rumor at the Planning Commission meeting for Lacy, that the fire department requirements for
turn around was going to be reduced or more flexible. I talked to Mike Alderson regarding his
requirement several weeks ago and he was reluctant to reduce it for this or any property.
Perhaps you would have more of an effect on Fire Department. Policy by talking to them.. I'm not sure
if you want to pursue this. I did talk to Jack about it and he said let it go (as far as the fire
department requirement for turn around goes). But as you can see I haven't let go yet. This project
is a perfect example where this type of requirement should not be implemented. If we don't reduce
the requirement for this single family residence, when will we do it?
Gary and I will be looking at this plan in regards to all the other issues of the site. Mr. Lacy/is under
some misconceptions regarding what we have agreed on, as I mentioned to you. so we will discuss
these and plan to meet with Mr. Lacy if not in person, at least on a conference call.
Thanks for your time.
C: Jack Pace
Gary Schulz
41Ip
Daylight In rceptor Trenches to Drainage Swales
2
vProposed Segmental Retaining Wall
1
Existing Drainage Path
•
tor Trench
c'.
Building Pad = 236' '\'
Property Line
12" Culvert
\
N
\ K-\\\
ZyZ
Proposed Interceptor Trench -� Quarry Silas
1— \ \
perty Line
-a,
Quarry 'Spalls
i
Reroute Existing Drainag:; Ditch \
\\
es -0 cz?neN \?‘
\ \ \ 1 1. 1 15 k T�
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\ \ I ' UN1MPt2ov
\, \ 1 \ r \ \
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V\ 229
sting Drainage Path`,
•
.5 5
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Scale: 1=20'j.
N
C QAOE
�'J CUL- Os 7;
.sed upon Boundary and Contour Survey for
F .1 4r 1-,‘,1 11,14 anA.Ao,arriatPG
PHONE LOG
May 24, 1995 10:35 a.m.
LACY Conversation
Mr. Lacy phoned asking if I received the plan. I said that I did and that Gary was out for 3 days so we
would have to talk about the wetland enhancement issues when he returned.
We discussed the fire truck turnaround and I asked if it was going to be paved. Mr. Lacy said he
intended to leave it gravel for a few years until the ground settled and then put in concrete. That way
his driveway wouldn't crack. I told him that the zoning code requires pavement of parking and
access. He disagreed and said that public works said it only had to be paved 20 feet from the road.
He asked if we required pavement on private property and he wants to see that section of the code. I
explained that the public works department administered the right-of-way of the road and that the
zoning code dealt with the parking and access. The zoning code requires that the driveway be
paved, but we don't require that the fire truck turn around be paved and either does the fire
department. I said that I would send him the section of the zoning code that speaks to pavement,
and that I would call him when Gary returned, next week.
City of Tukwila
6200 Southcenter Boulevard • Tukwila, Washington 98188 John W. Rants, Mayor
TUKWILA COMMERCIAL REAL ESTATE FORUM AGENDA
May 18, 1995 Doubletree Suites, Tukwila
3:00 Welcome/Overview
Market Advantages of Tukwila
3:15. Concurrent Sessions (offered twice)
The Emerging Land Use Plan
John Rants, Mayor of Tukwila
Bill Arthur, Co -Chair EDAB
Sarah Skoglund, Co -Chair EDAB
Ann Siegenthaler, Associate Planner
Vernon Umetsu, Associate Planner
Moira Bradshaw, Associate Planner
Market Opportunities in Tukwila Doug Klein, Kidder Mathews & Segner
Robert Larsen, Cushman & Wakefield
Ken Barnes, Cushman & Wakefield
Tukwila's Permit Process
3:45 Concurrent: Sessions Repeat
4:15 Question and Answer Session
5:00 Social Hour
6:00 Adjournment
Steve Lancaster, Planning Director
Ross Earnst, Public Works Director
Mike Alderson, Assistant Fire Chief
Bob -Benedicto, Senior Plans Checker
Opportunity to see broker&
Informational Displays
P: (206) 433-1800 • City Hall Fax (206) 4333
PHONE LOG
May 23, 1995
Lacy conversation
Mr. Lacy called said that the preliminary site plan is completed with the toe slopes. He will drop one
off today after 4:00 so that I can include it in the consultants review of the geotechnical report.
He said that the revision includes a fire truck turn -around and that the pond was eliminated and the
drainage moved to locate the turn -around.
We got into a discussion of the mitigation plan. He stated that he would not be doing any
enhancement to the east of his building pad. He said that in the hearing he had stated that after
talking with his attorney he was eliminating the ponds and that he was doing the enhancement to the
west at 1:1.5. He continued, saying that what he said was part of the record and because no one
objected he thought it was agreed upon.
I said that he did state that after talking to his attorney that he had decided to eliminate the pond, but
that he did not say he was eliminating all enhancement to the east of the building pad. Also Gary
stated at the hearing that he never said that Mr. Lacy had to do ponds for mitigation, but that if he
wanted to do ponding that would count for mitigation. I also said you can say what you want at the
hearing and make it part of the record, but that doesn't mean that approval was granted. I said that
the conceptional enhancement plan was part of the record and that the area know as C and D on the
plan were counted as mitigation areas and eliminating them as ponds does not eliminate them as
enhancement areas. I said it was not Gary's nor my understanding that you were eliminating all
enhancement east of the building pad and that there is a misunderstanding in what the City will
accept for enhancement. I said that it goes back again to the whole reason he went to the hearing, to
allow development with the least impact to the existing wetlands.
Mr. Lacy said that the interceptor drains would dry out the building pad and the property east of the
pad. I said that the intention should be to dry out the pad only and allow as much area east of the
pad to remain wetland or be enhanced to remain wetland. The conceptional enhancement plan
showed these areas as enhancement areas. If you are making such a drastic change to the
conceptional enhancement plan from what was approved by Gary and what the Planning Commission
viewed at the hearing, then we definitely need meet.
Mr. Lacy said that he couldn't keep taking off from work. He continued his argument that no one
objected to him eliminating the ponds and that he only had to do 1:1.5 enhancement. He said that
yes the con conceptional enhancement plan does not reflect what he intends to do for enhancement
and that he didn't want to spin his wheels.
I suggested again that we meet because there is obviously a misunderstanding as to what we can
agree on with respect to wetland enhancement on the site. I said that Gary and I could do a phone
meeting if that would be better for him. He thought that might work. I agreed that I would talk to Gary
on what he was proposing and give Gary a copy of the plan he is submitting today. Mr. Lacy said
that he would drop off two copies.
Mr. Lacy requested a copy of the draft minutes and a copy of the tape. I had him talk with Sylviia
Shnug.
May 12, 1995
•
City of Tukwila
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
Mr. Rodger E. Lacy Sr.
3125 S. Dakota Street
Seattle, WA 98108
RE: SEPA review, E95-0010
Dear Mr. Lacy:
The purpose of this letter is two -fold. First, to outline what are the outstanding concerns the City has
regarding this proposed development and secondly, to request additional information to complete the
SEPA (State Environmental Policy Act) review process.
Your project has been granted conditional approval of an exception from the Sensitive Areas Overlay
Zone to develop a single family residence. The four conditions attached to the approval are intended
to lessen the impacts of development to the existing sensitive areas on the property.
You have been granted permission to proceed with proposal for development. We are currently doing
an environmental review of the proposal through the SEPA process. As part of this process, the
following concerns need to be addressed prior to issuing a SEPA determination.
1. Geotechnical Report
Peer review of the geotechnical report will be conducted for this project. The City is
contracting with a geotechnical engineering firm and needs all revisions to the proposal
(including building pad location, revised preliminary drainage plans, etc.) to be submitted as
soon as possible so they may be included in the peer review. Please submit any revisions by
May 25, 1995.
2. Drainage
The drainage plan needs to meet the City standards (IGng County Storm Drainage Manual),
by maintaining pre -development stormwater runoff levels. Mr. Paul Stoltenberg has discussed
the site drainage with Phil Fraser, of Tukwila Public Works. According to Mr. Fraser, Mr.
Stoltenberg stated that there will be no increase in stormwater and no adverse impact to the
off-site storm drainage system. This needs to be stated in the proposed drainage plan as part
of SEPA review.
There is remaining concern that the interceptor drains will adversely impact the downslope
wetlands intended for enhancement. The on-site drainage management plan needs to
consider the impact to wetlands, and propose means to lessen impacts to pre-existing
wetlands as part of the SEPA review.
3. Access
Please provide the intended location of access to the property so that we can assess the
potential impacts of development. Maximum slope allowed for your access driveway if 15%.
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 e (206) 431-3670 • Fax (206) 431-3665
• •
Sewer and Water
Pat Brodin, of the City's Public Works Department, has had discussions with you regarding
sewer and water connections for your property. Water is available to serve the property for
both water connection for the property and fire protection requirements. However sewer is not
located adjacent to the property and a sewer extension is required to develop this property.
Public sewer lines are located in S. 158th Street and 53rd Avenue. Please identify which line
you intend to tie into, the length and location of the sewer extension, size of pipe, and number
of residences the system will serve. The sewer extension requires a 10 foot maintenance
easement.
Once I have received the requested information and peer review has been completed and discussed
with your geotechnical engineer, I will be able to complete the environmental review and the SEPA
can make the SEPA determination. Please provide the requested information at your earliest
convenience so that the review process can continue.
If you have any questions I can be reached at 431-3670.
Sincerely,
LILL
Libby Hugon
Associate Planner
.cc: Steve Lancaster
Jack Pace
Gary_Schulz
Ron Cameron
Phil Fraser
Joanna Spencer
Pat Brodin.
Linda Cohen
• •
Lacy chronology May 11, 1995
First contact with Mr. Lacy was at the counter with his son in the late fall, early winter of 1994. I
showed him the sensitive areas map of the property and copied the portion of the map the showed
the property he was interested. The property, north of Crystal Spring park had sensitive slopes,
streams and potential wetlands. I copied the Sensitive Areas Overlay Zone section of the TMC and
briefly explained the purpose and portions that pertained to the property he was interested. After
giving Mr. Lacy all the information I had available at the counter I suggested that he contact our Urban
Environmentalist, Gary Schulz, who would be able to assist him further regarding the sensitive areas.
I wished Mr. Lacy good luck on his project and he left the counter.
1/6 Mr. Lacy submits letter requesting an exception from the SAO
1/13 Drafted application for SAO exception and sletter explaining the process to Mr. Lacy. Draft
reviewed by Jack.
1/18 Letter and application w/SEPA sent out. Hearing set for 2/23/95.
1/24 phone call to Mr. Lacy. notes in file J
1/25 Meeting with Jack and Gary
1/26 Meeting with Gary and Mr. Lacy notes in file.
2/15 Mr. Lacy phoned, survey delayed
2/16 Letter to Mr. Lacy moving the hearing. to April 27, 1995 , with submittal date of 3/23
2/17 Lacy plan due to our office
3/7 Met with Gary on Lacy
3/8 Met with Jack and Gary on Lacy later meeting ith Steve - Jack met with Steve w/o meet to
breif him on the project.
3/8 Met with Gary and Mr. Lacy notes in file.
3/17 Geotech Report received
3/23 received application, SEPA and part of required plans. Lacy will submit remaining plans next
week
3/30 through 4/11 vacation for me
4/3 Meeting without me. Public works folks Gary and Mr. Lacy regarding access issues. Lacy
submitted conceptual mitigation plan
4/14 public notice mailed
4/17 staff report completed
4/19 Memo from Gary on enhancement plan
4/27 public hearing
Date: 11 -May -95 11:30
From: MOIRA-LIBBY (MOIRA BRADSHAW / LIBBY HUDSON)
To: JOANNA
Copies -to: GARY-SCHULZ,JACK,MOIRA-LIBBY,PHIL,RON-C
Subject: RE: Lacy special exception
Importance: HIGH
Message -id: 46F5B12F01DEDEDE
In -reply -to: OBD2B12F01DEDEDE
>Date: 11 -May -95'08:59
>From: JOANNA (JOANNA SPENCER)
>To: MOIRA-LIBBY (MOIRA BRADSHAW / LIBBY HUDSON)
>Subject: RE: Lacy special exception
>Date: 3 -May -95 16:42
>From: MOIRA-LIBBY (MOIRA BRADSHAW / LIBBY HUDSON)
>To: JOANNA (JOANNA SPENCER)
>Subject: Lacy special exception
>Ron -
>I need to complete the SEPA for the Lacy project. Please have peer
>review completed on the Geotechnical report as soon as possible.
>We also have some issues that need resolution before the SEPA
>determination can be made.
>I need comments on the storm drainage, access to the property, sewer and
>water connection, and any other comment/information your department
>feels
>should be included in the SEPA review.
>I have been working with Phil on the drainage issues, but these need to
>be discussed further, including the impact to the existing wetlands on
>the site. I need to get together with Phil and Gary Schulz early next
>week. Perhaps you need to attend also?
>Let me know what day (TUESDAY, WED OR THURS AM) is best.
>Thanks LIBBY
>Re:your sepa review letter, dated may 10,95 for Lacy SFR
>I met w/phil fraser on 5/10/95 and have his comments.Pat Brodin also
>participated in this meeting. Mr Lacy has called Pat several times
>regarding sewer & water connection to his property and Pat gave him
>some suggestions how to proceed. Phil said that the issue of sewer
>and water should be addressed in this letter as well. We should meet
>w/Pat today to wrap it up. I'm open except for DRC 1;30-3:00.
> Thanks,
> joanna
Joanna,
I've talked to Gary on the Lacy letter (set to go out tomorrow). He feels that
we should give Lacy 2 weeks from letter date to submit preliminary revised
plans for the geotech peer review. Does that hold up the geotech review too
much?
In the draft letter for the contract with Shannon & Wilson, we need some
verbege that includes review and alaysis of alternitives to the closed system
for the interceptor drains. Could allowing a portion of the water colllected
by the interceptor drains be directed to downslope wetland areas without
compromising the slope stability? Hydrology questions need to be answered too.
Does the proposal effect the downslope hydrology to the extent that the
existing wetlands, intended to be preserved and enhanced, are eliminated or
dried out?
•
We need to include these issues in the geotechnical review. The revised
proposal, as altered after the hearing of April 27, in response to the
conditions, needs to be included in the geotechnical review. Jack has stated
that we have funds in our department for this peer review if that is a problem.
May 10, 1995 10:10 am
Phone Conversation
Roger Lacy
RE: Lacy SEPA E95-0010
I phoned Mr. Lacy to set-up a meeting with him, his geotechnical engineer, Phil Frazer, Gary Schulz
and my self to discuss the revised site plan, and insure that the geotechnical engineer was moving in
the direction agreeable to the City. I explained that Phil and Gary still had some concerns regarding
the revised proposal. Specifically how the drainage would impact the wetlands and how on-site
retention would be obtained. I wanted to make sure that there was an understanding by all parties
before final design occurred.
Mr. Lacy stated that his geotech had met with Mr. Frazer and that Phil agreed that if he met the IGng
County Design Manual the drainage design would be adequate. I expressed both Phil and Gary's.
concerns regarding how the drainage would be retained and released on- site, and that it would be
best if we all sat down and discussed the site plan revision and how it relates to the unresolved
drainage issues. Mr. Lacy did not want to meet and stated that all those issues were resolved at the
hearing and with the geotechnical engineers discussion with Phil Frazer after the hearing.
I urged Mr. Lacy to meet with us to insure that there was no misunderstanding in what the City could
approve in regards to the revision to the site plan and how the drainage plan relates to the wetland
areas. I stated that it was for his benefit to make sure that he is going in the right direction before he
goes into the final design of the project.
Mr. Lacy said that the City could not make him change his plan from what was agreed at the hearing
on April 27th. I stated that the approval was only for permission to build on property significantly
impacted by the Sensitive Areas Overlay Zone, and that certain conditions were applied to insure that
the developments adverse impacts were limited. I went over the condition to reduce the development
area (#1) and the condition provide an wetland enhancement plan (#4). I explained that if we could
not meet now to insure that were are in agreement, I would need to include the issues in the
environmental review process. He argued with this, said the City was trying to stop his development,
and threatened suit, saying we were treating him unfairly. Mr. Lacy said that Gary Schulz had advised
him against buying the property and that Gary was trying to stop development of the property.
I said that this was not the case, that Gary was not trying to stop his development. I said that we
were being fair to him and that the processes he was going through were required for this type of
development. I reiterated that we were certainly not trying to stop his development, we had
recommended approval. I explained that it was his prerogative to sue but that he had no basis. I
stated that I was not going to argue about what transpired at the hearing again, and that I would
make the request in witting for additional information to resolve the outstanding issues.
I said that I would send a letter, listing the items we needed to finish the environmental review.
May 10, 1995
Phone Conversation of Tuesday, May 2, 1995
Roger Lacy
RE: Lacy SEPA E95-0010
I spoke with Rodger Lacy and discussed the hearing of April 27. I said that I would send a letter
regarding the conditions of approval, but that I wanted to listen to the tape first. He had some
questions regarding the specific conditions. I read the wording of condition #1 and the changes to
the wetland enhancement condition, (#4 in the final conditions). He had a question about the land
altering condition (#3 in the final), and I explained that this meant he could not do any altering of the
slope that was not approved. If at a later date he wished to do additional land altering he would have
to request an exception again.
He had a concern about the enhancement condition, requiring that the wetland enhancement plan be
installed prior to issuance of the building permit. Mr. Lacy said that he could not get financing without
a building permit and that some of the work should be completed later after construction of the house
and driveway or the enhancement would be ruined during the construction process. He suggested
that the enhancement be required at the time of Certificate of Occupancy. I re -read the condition and
told him that he could proposed phasing of the wetland enhancement as part of the plan. We could
look at the phasing and determine if it was acceptable. I explained that the enhancement is crucial to
this project and that requiring it prior to issuance of the building permit gives the City assurance that
the enhancement will be completed. It is the City's experience that leaving this type of requirement to
the Certificate of Occupancy has not worked in the past. I told him we could discuss this further when
he had an enhancement plan for us to review.
Mr. Lacy said that his geotechnical engineer had been to speak with Phil Fraser regarding the
drainage issues. He said that the engineer was working on a revised site plan and would have it for
us to look at next week. I asked if the geotech had discussed the proposed revision with Gary Schulz
and Mr. Lacy thought so, but wasn't sure.
Mr. Lacy then discussed the hearing, saying that City staff did not talk enough with his staff. He went
on about how we had made him move his house and that we were requiring him to alter his building
plans. I explained that we were trying to reduce the impacts to the sensitive areas and that what we
proposed was with this intention.
Mr. Lacy said that he had the was going to sue the City if we made him change his house at all. He
said he had his lawyer there at the meeting because he was going to sue the City if he wasn't allowed
to build his house and yard. He said that we had pulled a fast one on him and he said that 1 was
being underhanded in dealing with him. I told him that I resented that accusation. I explained that I
have kept him informed about every step of the process, assisting him where I could, and that I
apprised him of the proposed conditions and staff position prior to sending him the final staff report.
Mr. Lacy apologize, and said that he didn't mean to imply that I wasn't helping him in his project.
I then ended the conversation saying that I would be in touch next week regarding the SEPA review.
May 4, 1995
•
City of Tukwila
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
Mr. Rodger E. Lacy Sr.
3125 S. Dakota Street
Seattle, WA 98108
RE: NOTICE OF DECISION OF SENSITIVE AREA EXCEPTION/SPECIAL PERMISSION.#L95-0001
Dear .Mr. Lacy:
On April 27, 1995, the Tukwila Planning Commission granted conditional approval of your request for
exception from the Sensitive Areas Overlay. The conditions are as follows:
1. The applicant shall revise the site plan to reduce the area of development impact
through interceptor pipes, fill material, and toe walls, as recommended by the
geotechnical engineer.
2. The following site development measures shall be followed, as recommended in the
geotechnical report (Gali Group, March 15, 1995):
a. All grading and site preparation work shall be conducted during the dry
season.
b. All cut slopes shall be protected from erosion during construction and shall be
re -vegetated immediately after completion of grading activities.
c. Geotechnical observations and testing, by a Washington State licensed
geotechnical engineer, shall be conducted during site preparation and
grading to insure that proposed slope stability measures are effective.
3. All land altering shall be limited to the area defined by the approved site plan and
geotechnical study.
4. The applicant shall submit for review and approval to the Department of Community
Development (DCD), a final wetland enhancement plan at a ratio of 1.5:1; and shall
install all required wetland enhancement, as approved by DCD, prior to the issuance
of the building permit.
The Planning Commission's decision may be appealed to the City Council within ten days of the
decision. If you have any questions regarding the Planning Commissions action, please contact me at
431-3670.
Sincerely,
�/kh
Libby Hison
6300 Southcenter Boulevard. _Suite #1On • TnkwfL Wachlnotnn OR 1 RR . ronA1 47.7_2A 7/1 c...,. ions) ASI .1.4Ar
gate a =Kay= 5
yrom: MOIRA-LIBBY (MOIRA BRADSHAW / LIBBY HUDSON)
ro: RON-C
2opies-to: GARY-SCHULZ,MOI_.-LIBBY,PHIL
Subject: Lacy special exception
Importance: HIGH
Message -id: D596A72F01DEDEDE
Ron-.
I need to complete the SEPA for the Lacy project. Please have peer review
completed on the Geotechnical report as soon as possible.
We also have some issues that need resolution before the SEPA determination can
be made.
I need comments on the storm drainage, access to the property, sewer and water
connection, and any other comment/information your department feels should be
included in the SEPA review.
I have been working with Phil on the drainage issues, but these need to be
discussed further, including the impact to the existing wetlands on the site.
I need to get together with Phil and Gary Schulz early next week. Perhaps you
need to attend also?
Let me know what day (TUESDAY, WED OR THURS AM) is best.
Thanks LIBBY
111
Date: 3 -May -95 13:38 •
From: MOIRA-LIBBY (MOIRA BRADSHAW / LIBBY HUDSON)
To: DON
Copies -to: MOIRA-LIBBY
Subject: Lacy Sensitive Area Exception, L95-0001 & E95-0010
Message -id: 5D87A72F01DEDEDE
Don,
I received your memo of April 14, 1995, regarding the Lacy project and would
like to address your questions. First, I would like to explain what project
stage we are. Last Thursday the Planning Commission granted approval of a
special exception from the sensitive areas ordinance for development of a
single family house (with a number of conditions). I'll send this to you. The
proposal is now in SEPA, environmental review. After the SEPA determination is
made than the applicant may apply for his building permit.
Now to your questions -
1. Off-site impacts, specifically "backup" of natural drainage into the
Crystal Springs Park.
The applicant is not permitted to adversly effect off-site properties. The
proposal includes constructing interceptor drains which catch the surface and
subsurface water and direct this water either to the storm drainage system or
possibably to on-site detention. The drainage system has not been resolved
yet, but resolution will occur during the SEPA review process. The applicant
is not currently proposing anything that will cause ponding on the park
property.
2.Driveway access
Mr. Lacy has not resolved the access issues at this time. He has two options
available to him. His first solution is to use the existing roadway on the
site which crossess property owned by the Washington Dept. of Transprotation.
Mr.Lacy is atttempting to obtain permission to use this property for his
access.
The alternative is to use the existing unimproved right-of-way for S. 158th
Street. This option will require him to destroy an existing retaining wall and
construct a new wall to maintain slope stability and accomodate his access
drive.
The first option will not impact the adjacent park. The second option means
cutting into the slope within the public right=of-way, not on park property.
There is some concern for slope stability. Measures to insure that the work is
done in dry weather, erosion is controlled and that the slope is stabilized and
revegetated should be addressed. If these measures are followed, then the
access drive construction should not adversly impact park property.
3.Fencing
The applicant is considering placing a fence and gate across the east end of
his property. According to his survey there is an existing fence located
within the middle of the unimproved right-ofway of S. 158th Street. This
right-of-way borders the north side of the park.
I hope this answers your question. I will condition the SEPA to include ;the
measures discussed in the S. 158th Street access drive alternative. If you
have ;any other concers=ns regarding this project, please let me know.
Thanks.
Libby
•
atty Thkwli
6200 Southcenter Boulevard ° Tukwila, Washington 98188
MEMORANDUM
TO: Libby Hudson, Associate Planner
FROM: Don Williams, Director of Parks and Recreation
DATE: April 14, 1995
SUBJECT: Lacy Sensitive Area Exception
John W. Rants, Mayor
A review of the SAO Reasonable Exception Application form and the Environmental
Checklist does not provide sufficient information for me to respond about three concerns.
1. What impact will the development of the site have on the natural flow from spring
water and surface water within the Crystal Spring Park? Will such development
"backup" water flow into the park or change water table levels?
2. The information is limited about the driveway access to the house. Will it be next
to the park property? How will the driveway be drained?
3. The north side of the park has no fence. Will the developer be installing a fence to
separate the two sites? Until these questions are answered, I cannot respond with
any other comments.
DW/dc
Attachment
RECEIVED
APR 1 4 9995
COMMUNITY
DEVELOPMENT
Phone• (206) 433-1800 ° City Hall Fax (206) 433-1833
•
•
WATERSHED DYNAMICS, INC.
.. _. _ I`;.Yw-..y,. K -:.F p+. .. , :�.•�,�•. tY:: iS'.":'T C: •• �r_..l.r,+� ^^"J^: FT�t; ,yz¢,+1•yt.h:. .
%.d,.:.uxc.,u.«Yi-�_,..ar.a....u.a.xw:,�iuti..z6i u�v2irv,:SnbaS."md:r{arma.7...S,m%`...�,e".Ir3t::-7�e!.4Sh� t::. ad....�s.i,...�..-..u..
March 21, 1995
Mr. Gary Schulz
Urban Ecologist
City of Tukwila
6300 Southcenter Blvd.
,Tukwila, WA 98188
Dear Gary,
Enclosed are data forms (SP1A - SP12A) and my non -surveyed site map for the
Lacey site. I can also. send you copies of my field notes, if you like.
This computerized data form is new, so please excuse any format errors you
may find. We're still working out the glitches.
Respectfully,
ave Risvold
Project Biologist
FISHERIES, HYDROLOGY, WATER QUALITY & WETLANDS
1833 Auburn Way N. Suite F • Auburn, WA 98002 • (206) 735-4288, FAX (206) 735-4289
RECEIVED
MARR 2 11995
COMMuk,
DEVELOPMENT
EXISTING ROAD
CORRIDOR/TRAIL
,r7 PHOfERTY BOUNDARY
DRAINAGES
/ \
#2 #3
SPIA
SP2A\
##4
.• ASP3A
SP4A '' Y r t ' ' •
i
t , . 1 ' , , '.,I`I
SP9A ' 11SP7A., ) ,II,
30Q•� •
B SP9A NOTA SURVEYED MAP
i , P6�4 ' , •.1
,' ',' f �,
H ' +'• t \
B
2�"' •SPIOA,`••* 9 • '1 .+%�� EXISTING
''I ' ' ' , Q rCULVERT.
SPI ' !, /`,
S` , FLAG A8
' `, //
'F y ' f 10�_,ISPI2A '/ SPeA
6/ /
J+'. //
00
NS)4 1c
/ ./
CABLE /� / /
GATE" / /
THIS AREA NOT
EVALUATED
51ST AVE SE
EXISTING
CULVERT
4.f IDENTIFIED
WETLAND AREA
= APPROX. CENTERLINE
OF DRAINAGE
s= APPROX. SAMPLE PLOT
LOCATION
LACY PROJECT SITE
WATERSHED DYNAMICS.
1421 17TH STREET S.C.
AU:UM. FHA 96002
(206) 733-4288
ENVIRONMENTAL CHECKLIST
Purpose of Checklist:
K 4I- ooto
The State Environmental Policy Act (SEPA), chapter 43.21C RCW, requires all governmental agencies
to consider the environmental impacts of a proposal before making decisions. An environmental impact
statement (EIS) must be prepared for all proposals with probable significant adverse impacts on the quality
of the environment. The purpose of this checklist is to provide information to help you and the agency
identify impacts from your proposal (and to reduce or avoid impacts from the proposal, if it can be done)
and to help the agency decide whether an EIS is required.
instruction for Applicants:
This environmental checklist .asks you to describe some basic information about your proposal. The City
uses this checklist to determine whether the environmental impacts of your proposal are significant,
requiring preparation of an EIS. Answer the questions briefly, with the most precise information known,
or give the best description you can.
You must answer each question accurately and carefully, to the best of your knowledge. In most cases,
you should be able to answer the questions from your own observations or project plans without the need
to hire experts. If you really do not know the answer, or if a question does not apply to your proposal,
write "do not know" or "does not apply". Complete answers to the questions now may avoid unnecessary
delays later.
Some questions ask about governmental regulations, such as zoning, shoieiine, and landmark designations.
Answer these questions if you cam If you have problems, the City staff can assist you.
The checklist questions apply to all parts of your proposal, even if you plan to do them over a period of
time 'or on different parcels of land. Attached any additional information that will help describe your
proposal or its environmental effects. The City may ask you to explain your answers or provide additional
information reasonably related to determining if there may be significant adverse impact.
Use of checklist tor nonproject proposals:
Itionproject proposals refer to actions which are different or broader than a single site specific development
project, such as plans, policies and programs.
Complete this checklist fornonproject proposals, even though questions may be answered "does not apply".
In addition, complete the supplemental sheet for nonproject actions (part D).
For nonproject actions, the references in the checklist to the words "project", "applicant",. and "property
or site" should read as "proposal", "proposer", and "affected geographic area", respectively.
ENVIRONMENTAL CHECKLIST
A. BACKGROUND
1. Name of proposed project, if applicable:
2. Name of applicant:
Cont. No.
Epic File .No.
Fee $ 325 Receipt No.
3. Address and hone number of applicant and contact person:
31 Jr-' 50- DUE std 5eu l'1'21 Z'Wr , 9s'lag • 7.2.a.077
4. Date checklist prepared: -3 —ao —d1
5. Agency requesting Checklist:
City of Tukwila
6. Proposed timing or schedule (including phasing, if applicable):
SIN LO
7. Do you have any plans for future additions, expansion, or further activity
related to or connected with this proposal? If yes, explain. lo
8. List any environmental information you know about that has been prepared, or will
be prepared, directly related to this proposal.
9. Do you know whether applications are pending for governmental approvals of other
proposals directly affecting th property covered by ,You.r, ,proposal? If yes,
explain. e ,, i•� • -h •cc.- .1/.
7
•-G-
RECEIVED
MAY 3 1995
COMMUNI 1 Y
DEVELOPMENT
• •
10. List any government approvals or permits that will be needed for your proposal.
11 Give brief, complete description of your proposal, including _the proposed uses
and the size of the.project and site. There are several questions later='in this
checklist that ask you to describe certain aspects of your proposal. You do not
need to repeat those answers on this page. Section E requires a complete
description of the objectives and alternatives 'of your proposal and should not be
summarized her
� ;;)L/ CBI Lee
514e 19/12..4: Doo
Lthq_appzeix 1Sob 530
-
12. Location of the proposal. Give sufficient information for a person to understand.
the precise location of your proposed project, including a street address, if
any, and section, township, and range, if .known. If a proposal would occur over
a range of area, provide the range or boundaries of the site(s). Provide a legal
description, site plan, vicinity map,and topographic map, if reasonably
available. While you should submit any plans required by the agency, you are not
required to duplicate maps or detailed plans submitted with any permit.applica-
tions related to this checklist.
"trot 5uda.Je, 1 isieAi--rov_Lev5L g,3412.2
o -s1-
13. Does the proposal lie within an area designated on the City's Comprehensive Land
Use Policy Plan Ma as environmentally sensitive?
YP S: C /u5s W 2-i'1 u ry S a,u 0/4.5 $$l o pQS 4c.4 -/-e c J
-3-
•
TO BE COMPLETED BY APPLIC
411 Evaluation for
Agency Use Only
B. ENVIRONMENTAL ELEMENTS
1. Earth
a. General description of the site (circle one): Flat,
C21114;) hilly, (steep slopes, mountainous, other
b. What is the steepest slope on the site (approximate
percent -slope)? .5670 670 the toe vAi
c. What general types of soils are found on the -site
(for example, clay;.sand', gravel peat, muck)? If
you know the classification of agricultural soils,
specify them and note any prime farmland. '
au Sj )oCPnitS1
�•
op.
d. Are there surface indications or history of unstable
soils in the immediate vicinity? •If so, describe.
4P-56uf hof' (3)%i - i.S 1-44 b + 50-
9ork 'I reeS op adj
e. Describe the purpose, type, and approximate quanti-
ties of any filling or grading proposed. Indicate
.source of fill.
f. Could erosion occur as a result of clearing,
co struction, or use? I1f so, gener.11y describe.
€ S' la y_cya,cibV • , ! 640
Er
g About what percent of the site will be covered with
impervious surfaces after project construction (for
example, asphalt or buildings)?
—70 / %
-4-
Evaluation for
Agency Use Only
h. Proposed measures tb reduce or control erosion, or
other impacts to the earth, if any:
2. Air
a. What types of emissions to the air would result from
the proposal. (i.e., dust, automobile odors,
industrial wood smoke) during construction and when..
the project is completed? if any, generally
describe and give approximatequantities if known'.:
b. Are there any off-site sources of emissions or odor
that may affectyour proposal? If so, generally
describe.
c. Proposed measures to reduce or control emissions or
other impacts to air, if any:
3. Water
a. Surface:
1) Is there any surface water'body on or in the
immediate vicinity of the site (including year-
round and seasonal streams, saltwater, lakes,
ponds, wetlands)? If yes; describe type and
provide names. If appropriate, state what
stream or river it flows into.
`�GSZ��SS wd
-5-
410
• Evaluation for
Agency Use Only
2) Will the project require any work over, in, or
adjacent to (within 200 feet) the described
waters? If yes, please describe and attach
available plans.
ye, 5 } Se.e 574-P- pia_
3) Estimate the amount of fill and dredge material
that would be placed in or removed from surface
water or wetlands .and indicate the area of the
site that would. be affected.- indicate the
source of fill material.
Se P- &7ec eGh/u7C f44 . Mod S /te, .
ria -To.
4) Will the proposal require surface water
withdrawals or diversions? Give general
description, purpose, and approximate quan-
tities, if known. '>/e u,
5) Does the proposal lie within a 100 -year
floodplain? If so, note location on the site
plan. X10.
6) Does the proposal Anvolve any discharges of
waste materials to surface waters? If so,
describe the type of waste and anticipated
volume of discharge.
830.
-6-
b. Ground:
IIIEvaluation for
Agency Use Only
1) Will ground water be withdrawn, or will water be
discharged to ground water? Give general
description, purpose, and approximate quan-
tities, if known.
//
dao
2) Describe waste materials that will be discharged
into the ground from septic tanks or other sour-
ces, if any .(for 'example: 'Domestic' sewage;
industrial, containing the following
chemicals...; agricultural; etc.) Describe the
general. size of the system, the number of such
systems, the number sof .houses to be served (if
applicable), or. the number of animals or humans
the system(s) are expected to serve.,•
D es_1vof 019 l,,f
c. Water Runoff (including storm water):
1) Descr-3e the source of runoff (including storm.
water) and method of collection and disposal,.
any (include quantities; if known). Where will=`
this water flow? Will. this water flow into
other waters? If so, describe.'
L
411
Evaluation for
Agency Use Only
2) Could waste materials enter ground .or surface
waters? If so, generally describe.
d. Proposed measures to reduce or control surface,
ground, .and runoff -water impacts, if any:
) e5 ) -yam el r_JiJQ11 / Op
4. Plants
a. Check or circle types of vegetation found on the
site:
-1l deciduous tree:
t/ evergreen tree:
,/ shrubs
V' grass
pasture
crop or grain
aspen, other
pine, other
v wet soil plants:' .cattail buttercup builrush,
gkunk cahbage)other •
water plants: water lily, eelgrass, Lnilfoil, other r�. -1—
V. other types of vegetation s� we 1�� ole l�i��"h ��
b. What kind and amount of vegetation will be removed
or altered?
cte i N eci -t-to iV @r ek
c. List threatened or endangered species known to be on'
or near the site.
des 1LJc)clef
-8-
Evaluation for
Agency Use Only
d. Proposed landscaping, use of native plants, or other
measures to preserve or enhance vegetation on the
site, if any:
-----;"-1 adrubi0 WTI
--447AAllur6 0 e-ro ee
cues-frtevvva
5. Animals
a. Circle : any . birds and animals which have been
observed on or near the site or are known to be on
or near the site:
birds:
heron, eagle, other:
mammals: deer, bear, elk, beaver, other:
. fish: bass, Salmon, trout, herring, shellfish,
other:• D2 -e-5 )L4 kypi y
b. List any threatened or endangered species known to,
be on or near the site.
72e_e54k_apply
c. Is the site part of a migration route? If so,
explain.
r
d. Proposed measures to preserve or enhance wildlife, - • .
if any:
pre 5eyve_. 6k.) a +CA
blCiiM -Or
.
-r-r-tboA3 CliJe4
-9-
6. Energy and Natural Resources
Evaluation for
Agency Use Only
a. What kinds of energy (electric,'.natural gas, oil,.
wood stove, solor) will be used to meet the
completed project's energy needs? Describe whether
it will be used for heating, manufacturing, etc.
b. Would your project affect the potential use of solar
energy by adjacent properties?......If so, generally
describe.
0
c. What kinds of energy conservation features are
included in the plans of this proposal? List other
proposed_ measures to reduce or control energy
impacts, if any:
7. Environmental Health
a. Are there any environmental health hazards,
including exposure to toxic chemicals, risk of fire
and explosion, spill, or hazardous waste, that could.
occur as a result of .this proposal? If so,
describe.
Alp
1) Describe special emergency services that might
be required.
2) Proposed measures to reduce or control environ-
mental health hazards, if any:
-10-
411
Evaluation for
Agency Use Only
b. Noise
1) What types of noise exist in the area which may
affect your project (for example: traffic,
.equipment, operation, other)?
2) What types and levels of noise would be created
by or associated with the project on a short-
term or a long-term' basis '(for example: .traf--
fic, construction, operation, other)? Indicate.
what hours noise would come from the site.
0;00 Ai
0
.r1
3) Proposed measures to reduce or control noise
impacts, if any:
8. Land and Shoreline Use
a. What is the current use of the site and adjacent
properties?
b. Has the site been used for agriculture? If s
describe.
c. Describe any structures on the site.
-11-
SEvaluation for
Agency Use Only
d. Will any structures be demolished? If so, what?
1)0e5 Paor 40T-ly
e. What is
site?
e current zoning classification of the
la
f. What is the c rrent comprehensive plan designation
of the site? L0 yvyo Oulu L-oui cieP eAcizi
g. if applicable, what is the current shoreline master
program designation of the site?
Poe5 ' fipp1\
h. Has any part of the site been classified as an
"environmentally sensitive" area? If so, specify.
C/45s
i. . Approximately how many people would reside or work
in:the completed project? 4-6 5'
j. Approximately how many people would the completed
project displace? Q1103)_e,____
k. f"posed measures to avoid or reduce displacement
impacts, if any:
L)o'5 aJz ./1p
/27
1. Proposed measures to ensure the proposal is com-
patible with exi ting and projected land uses and
plan/s, if. any: 1N9 t1i1lJ/ ()u)eIlIn1
bei ems-I,e,� c� n�� 49-1- Co p, p 1 &
-12-
III
Evaluation for
Agency Use, Only
9. Housing
a. Approximately how many'units would be provided, if
any? Indicate whether high; middle, or low-income
housing?
b. Approximately how many units, if any, would be eli-
minated? Indicate whether high,middle, or low-
income housing.
OC Aft)
c. Proposed measures to reduce or control housing
impacts, if any:
10. Aesthetics
a. What is the tallest height of any proposed
structure(s), not including antennas; what is the
principal exterior building material(s) proposed?
ff• `ol l rei eL
L 9/617A1
/u a
b. What views in the immediate vicinity would be
altered or obstructed?
c. Proposed measures to reduce or control aesthetic
impacts, if any:
-13-
411
Evaluation for
Agency Use Only
11. Light and Glare
a. What type of light or7gla're will"the.�•�pr"oposal
produce? What time of day would it mainly occur?
b. Could light or -glare from the finished project be a
safety hazard or interfere with views?
•
c. What existing off-site sources of light or glare may.
affect your proposal?
d. Proposed measures to reduce or control light and
glare impacts, if any:
12. Recreation
a. What designed and informal recreational oppor-
tunities are in the immediate vicinity?
b. Would the proposed project displace any existing
recreational. uses? If so, describe.
c. Proposed meauresto reduce or control impacts on
recreation, including recreation opportunities to -be
provided by the project or applicant, if any:
, )v+ cr pk/
-14-
13. Historic and Cultural Preservation
SEvaluation for
a. Are there any places or objects listed on, or pro-
posed for, national, state, or local preservation
registers known to be on or next to the site? If
so, generally describe.
b. Generally describe any landmarks .or evidence of
historic, archaeological, scientific; or -cultural
importance known to be on or next to :the site.,
c. Proposed measures to reduce or control impacts, if
any:
14. Transportation
a. Identify public streets and highways serving the
site, and describe proposed accss to the existing
street system. Show on site plans, if. any.
5 „Ave, 5, a N d 158Th 9"
kupi+ o -T . way
b. Is the site currently served by public transit? If
not, what is the approximate distance, to the nearest
transit stop? pp —; 1500 -P4"7"
c. How many parking spaces would the completed project
have? How many would the project eliminate?
3 at -
-15-
Agency Use Only
Evaluation for
Agency Use Only
d. Will the proposal require any new roads or streets,.
or improvements to existing roads or streets, not.
including driveways? __If so, generally describe
(indicate whether public or private).
v. tot.- Way --DUB pu i 1.G Iiv-tS
e. Will the project use (or occur in the immediate
vicinity of) water, rail, or air transportation? If
so, generally describe.
f. How many vehicular trips per day would be generated
by the completed project? If known, indicate when
peak volumes 'would occur.
— 7"w l c /kJ t e- •moN i jj t4 ew e1
o c� G--_ II, Iylft-
g. 'Proposed measures to reduce or control transpor-
tation impacts, if any:
15. Public Services .
a. Would the project result in'an increased need for
public services (for example: fire protection,
police protection, healthcare, schools, other)? If
so, generally describe.
b. Proposed measures to reduce or control direct
impacts on public services, if any.
l3(Ar ytCtygTarrz firms
-16-
16. Utilities
Circle utilities currently available 'at the. site:
electricity, natural gas, ater refuse service,
telephone, sanitary sewer, septic system, other.
. b. Describe the utilities that are proposed. for the
project, the utility providing the service, and the
general construction activities on the site or in
the immediate vicinity which might be needed.
. id
—
� �- tuilour fa
C. Signature
The above answers are true and complete to the best of
my knowledge. I understand that the lead agency
relying on them to m. e its decision
Signature:
Date Submitted:
is
PLEASE CONTINUE TO THE NEXT PAGE.
-17-
of cts
Evaluation for
Agency Use Only
TO BE COMPLETED BY APPLIC•
D. SUPPLEMENTAL SHEET FOR NONPROJECT ACTIONS
(do not use this sheet for project actions)
IIIEvaluation for
Agency Use Only
Because these questions are very general, it may be helpful
:to read them in conjunction with the list of the elements of
the environment. -•
When answering these questions, be aware of the extent the
proposal, or the types of activities. likely to result from
the (proposal, would affect the item'at a greater intensity
or at a faster rate than if the proposal were not imple-
mented, Respond briefly:and in 'general terms
1. How would the proposal be likely to increase discharge
to water; emissions to air; production, storage, or
release of toxic or hazardous, substances; or production
of noise?
axcep-h0)1)
Proposed measures to avoid or reduce such increases are:
2. How would the proposal be likely to affect plants, ani-
mals, fish, or marine life?
070
Proposed measures to protect or conserve plants, ani-
mals, fish, or marine life are:
-18-
Evaluation for
Agency Use Only
3. How would the proposal be likely to deplete energy or
natural resources? •a..
Proposed measures to protect or conserve energy and.
natural'resourses are:
4. How How would the proposal be likely to use or affect
environmentally sensitive areas or areas designated (or
eligible or under study) for governmental protection;
such as parks, wilderness, wild and scenic rivers,
threatened or endangered species habitat, historic or
cultural sites, wetlands, floodplains, or prime
farmlands?
437
Proposed measures to, protect such resources or to avoid
or reduce impacts are:'
)4-
5. How, Would the proposal be likely to affect land and
shoreline use, inclduing whether ,it would allow or
encourage land or shoreline !.,ses incompatible with
existing plans?
-19-
III Evaluation for
Agency Use Only
Proposed measures to avoid or reduce shoreline and land
use. impacts area:
A) 'A
How does the proposal conform to the Tukwila Shoreline
Master Plan?
6. How would the proposal be likely to increase demands on
transportation or public services and utilities?
o u- any ' I'iu& 10.r
e+
Proposed measures to reduce or respond to such demand(s)
are:
7. Identify, if possible, whether'the proposal may conflict
with local, state, or federal laws or requirements for
the protection of the environment.
-20-
411
Evaluation for
Agency Use Only
8. Does the. proposal. conflict with policies of the Tukwila
Comprehensive Land. Use Policy Plan? If so, what poli-
cies of the Plan?
C,i A
Proposed measures to avoid or reduce the conflict(s).
are:
-21-
',TO BE COMPLETED BY' APPLI. . Evaluation for
Agency Use Only
E. SUPPLEMENTAL SHEET FOR ALL PROJECT AND NON PROJECT
PROPOSALS
-The objectives and the alternative means of reaching the
objectives for a proposal will be helpful in reviewing the
aforegoing items of the Environmental Checklist. This
information provides a`. general overall_ perspective of the.
proposed action in the context of the environmental infor-
mation provided and the submitted plans, documents, suppor-
tive information, studies, etc.
1. What are the objective(s) of the proposal?
a i -- a 57.4,91,e, i 1
What are the alternative means of accomplishing these
objectives? '
Please compare the alternative means and indicate the
preferred course of action:
CiS C!T
-22-
Evaluation for
Agency Use Only
4. Does. the proposal conflict with policies of the Tukwila
-Comprehensive Land Use Policy Plan? If so, what poli-
cies of the Plan?
13011)
Proposed.. measures -Ito avoid: or reduce the: conflict(s).•
are:
-23
=Mgmmrrmmn
. 5 '57''O ST
5. 1601I 5
5. 162nd St
1
SPECIAL PERMiSSgON
S.A.O. REASOABLE EXCEPTION
APPLICATION
CITY OF TUKWILA
DEPARTMENT OF COMMUNITY DEVELOPMENT
6300 Southcenter Boulevard, Tukwila, WA 98188
Telephone: (206) 431-3680
ross-Reference Files: Receipt Number:
1. BRIEFLY DESCRIBE YOUR REQUEST: perm/55,07u `JOU ,b c t Id
G� SIiusI(2„ arvl%J y D ie%)jiu Gi. CI s
we /c nSGt Avec
2. PROJECT LOCATION: (Give street address or, if vacant, indicate lot(s), block, and sub-
division; or tax lot number, access street, and nearest intersection)
l Se >A' ,511. So, :T4 kw ll� w
Quarter: 6 Section: a a Township: 23 Ai Range: 7-1
(This information may be found on your tax statement)
3. APPLICANT:* Name: /1 GGYGC j� E 1�,/-�C,• Sr,
� y
Address: S / 02.E 90, Dgkv-M Sj $eaa ffie ) 6/96S:
Phone. (, D (a7. .-0'7 74
•
Signature: )0—Date: TTU nJ a0, Nets
* Thea hcanf is the person whom the staff will contact regarding theapplication,
PP g gand
to whom all notices and reports shall be sent, unless otherwise stipulated by applicant.
AFFIDAVIT OF OWNERSHIP
4. PROPERTY Name:vd Sy eir 4• h I lY / Lacy
OWNER
Address: 31025 SO , V 4 ko-/cr 5 � 9,iLJJe I L/l)}t Q%ak) r7
Phone: Ce(36) 7-677
I/WE,[signature(s)]
swear that I/we are the owner(s) o contract purchaser(s) of the property involved
in this application and that the foregoing statements and answers contained in this
application are true and correct to the best of my/our knowledge and belief.
Date: TiU a I) /q `1s
• •
SPECIAL PERMISSION - S.A.O. REASONABLE EXCEPTION APPLICATION
5. PRESENT USE OF PROPERTY?V'+
ac�ti
6. PROPOSED S.A.O. EXCEPTION (from TMC 18.45.115):
771 rf0 L)&ji5'C
WHAT IS THE TIME FRAME FOR CONSTRUCTION AND OPERATION OF THE
PROPOSED USE? M a y j 9 q�S
8. DESCRIBE THE MANNER IN WHICH YOU BELIEVE THAT YOUR REQUEST
FOR A REASONABLE EXCEPTION WILL SATISFY EACH OF THE
FOLLOWING CRITERIA AS SPECIFIED IN TMC 18.45.115(c)(4) (ATTACH
ADDITIONAL SHEETS IF NECESSARY)..
A. No reasonable use with less impact on the sensitive area and its buffer is possible.
RESPONSE: The, Lewei 11 a cr. t $ open eijr 11149 •
toe 5 �-e r) or bo n) h P� s-d,�2r c #\J Yf Ct nl d e r
va14rnac-t Seri J - he, ` iv�,1 h s 9 e-✓ 2v�t ,
' fvIa Gf,� Ginais?a D_ /.l ,1i,P ALS" t"v'ei'h i
toe ra,uta 7 h. i�rP r rs ? M4 sULy
Na#1,tx,l1� a c.( mart laiQ lej wei• tcridg, �y lJel a%
(ipug Jc „,TCS 0,v -fhv: i- i w1i/ lrvJpar+ 111p, gewsliiv� area /S
nr 1± 's lu-'-fess
B. There is no feasible on-site alternative to the proposed activities, including reduction in
size or density, phasing of project implementation, change in timing activities, revision
of road and lot layout, and/or related site planning activities that would allow a
reasonable economic use with fewer adverse impacts to the sensitive area and its
buffer.
l
RESPONSE: Ttie= eyrie, tit 5. ara.e. ion -e c'
NA r pfreSe r iod F'uf ve iveea s - The.v-g_. Fs
Coto - £ )U aSd .bui id4 nu _-ale, pi?) ri y
N ft S '&P_, Lea-�s t l L/ e, 1.vetle. l
bprause- 11 1.5 CI vv)vim riI.ec4 erre 1. 3
� y
{
SPECIAL PERMISSION - S.A.O. REASONABLE EXCEPTION APPLICATION
C. As a result of the proposed development there will be no increased or unreasonable
threat of damage to off-ite public or private property and no threat to the public health,
safety or welfare on or off the development proposal site.
RESPONSE: PG s' fk g e fire. t L2 -J-.ect c.r 1.Qt1/I,,oAs
et✓,u (
Lrth'
y S5d 4er 5/374e ret eve. 1 y,•lealLde" cS,1
e.
Droegt'-47QS
D. _ Alterations permitted shall be the minimum necessary to allow for reasonable use of the
• property.
1---e
Al
Atta -,
wr iviz aIQ, M �1L Gi/V� CL
tetli tit pe i, i y 110, 11e- oIrea -Io t ac 'd
c�, 1] b� -Aveal pi
l 6ev¢+eali toica I, bus_ t cJ0' 1 -
Y!tcortnia f r m --'dnitcarJ `Ti Arfof Gi Ma ii avd are—o(
far t✓1 I r�t 1GJve lt)� YuAf5c dvide- Way' areaior ofcc/_cc
E. The proposed development is compatible in design, scale and use with other
development with similar site constraints in the immediate vicinity of the subject
property.
RESPONSE: The. pe- 0e e%�j�'•�e, ?jt� 71 -Le...- Civic(Q v' +2- 5 /No j e , 0- ! i (c c� P I 1 ��v o� _ 'Melt ado Not' kalif.
Aft-Slrvlllu►^ �1*- Co7v 5•tratnAS beaus-er 1'1,e,y were.- b 4Ic/
floor % i'11,S reyulrfi ,0_
SPECIAL PERMISSION - S.A.O. REASONABLE EXCEPTION APPLICATION
F. Disturbance of sensitive areas has been minimized by locating the necessary
alterations in the buffers to the greatest extent possible.
G. The inability to derive reasonable use of the properly is not the result of actions by the
applicant in segregating or dividing the property and creating the undevelopab/e
condition after the effective date of the ordinance from which this chapter derives
(1991).
RESPONSE: 73V, 1 S Guo+ 51471;:ded Q n1 C/
►e h
d 73)01,1v, in eve_ Cati.S-ect lal eutaLi. 5
iv -e -s _
H. Any approved alterations of a sensitive area under this section shall be subject to
conditions as established by this chapter and will require mitigation under an approved
mitigation plan. If a development is approved as a reasonable use, the Board of
Architectural Review's process, review and standards shall be applied.
RESP NSE::. _'.r' , _ - 0-4 e M /--7 i cja-1 i )G U
CV i 11 c e ` "f'l►P. tri atrd-S c- 1.cJG�lalvd .h
-111 IL) ha RIC wi, C4� uS CIA- 4c b blew, b cry's r.v�:f - -1Z
P re,vtov ?'1,err5 /A Al d fhrtJ w$'jla-nr0�
p� u ►mss vOd i c1n./�^,•�'i%e'�2 s Good -►c 1--. P.,/1441) will
be cies -e loped *5 le -t,
�e5/ V Lc)
TRACT 47 449.00'
S89'33'02'E
—Flom 9 Ins.
11911111111.1.1.1i, •
_TVLW.Hare ace plow- Scaio: 1+20','
__IlR6.441 'Rx S -r -RM :bv;Tem \ # •..�' ✓ w
1 \ \ 1 , say• r \, r--''�— —v./sip.,` _N \ I\ \
\ mJ, i \ - 1 u�ilrsw.r F\ \ 1 .) �{LLN.1\\\ \\•O \\ \ \f^ 1, - LLG.0 C FILL) \
,f_..___- \ \ :. , /
,- '1 1 L<J _
w.t.rl:adouSiG \ `
tpa� \ o x�rtn1) \ \ cam. f 1 (° -- —
r \ �5
\ \ \ \ pwe�[a uv>ti�e �. eA A 0 \ \\\ wA<eacol:ase
\ \ \Lrre ecene0.rasa — ` ,.^\ • \ ` \ \ `<
C).._-, __ • •,d.9
l , \ , ` }7.99, _ {
\ 1 \ \ \ \ 1 3530' \ \ I
I 1 ► \ 1 152644\`O \\ 1 \\ �\ \ �N \\ \\ \\\�
Nato,:
1. Based upon Boundary and Contour Survey for godger E. lacy .5r.. by Lund and
Associates Surveyors. 2-28-95
2. See GeoreclricafInvestigation !eager E. Lacy5r. Reeldence, 51s:ArerueSCUM,
1'ukwiL Wi sli gtot 3-15-95, by Gab Group for mcommendationa on cut, fill, and
drainage.
3. Interceptor trench et top of proposed cut ehould be installed prior to regrading of
slopes.
4. Water colrx approac}dng building footprint from the west and the south should be
rerouted as pat of the landscaping and wetland mitigationpions. Interceptor
trench along south side of buildup footprint may need to drain Into rerouted
waterrglax.
Proposed Grading Plan
3- LI- 951
10. loalIVOHD .T.
11111.e0 46,4.
Rodger E. Lacy Sr. Residence
Tukwll.t Wall gton
r .0120,.,.I. • neoou.ahWay Ia. as.202
sutw Mrliyto. 0625 new (206)303,4441
Drardne1of3
zee'
t.30'
z1.5'
255'—
z5O.
V40'
tss'
t30'
es 6'
•. '
teriti 4. 6
- - - - _ - - - - - -
e•
Will .17,3 FC 4470-
5"6'' • yortICAI
5
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13
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re5.
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es5.
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u5.
Cross Sections A -N and L343'
: 6140.,1
1.2
POI111.1,
... E. Lacy Sr. Residence
v, ..„, ,,„
8
TRACT 113 z
\ TRACT 47 449.00. Drag, Interceptor r,.nzt,.ab.tonn,,.n.
conveyance . S89.33"02•E system
�� �� \\ - r_ r, _ ., \ \ \ \ \ \ \ \
---; ��\ 6 e., 1 \ \ \ \ •TP1 r = -�--� --,
-------, , \''2j \ \'O \ m N i 1 I 1} \ 1\ Roc 016.!.¢134.1 : \ \ \
�� \ \ \ r0 \ \ \ \ \ \\ \ \ \ oT. \\ c•'`s0 \ P ` r 'r 1 I I ✓ P4cIPox� bullclfrlg bca�rlpn 1 \\ \ \
iriscr, --_-\ / ) 1 I \ \ \ \ \\�\\\\ \ 0\ r C`ul � `1 / �Ii/I /\; \ I `'�. -- 0
— _ ` \ 1 \ / / / / ) \ \ 1T[tl \ T48 \ \ \ : / 2F6 1 I ' o / - 1 4 -i' F \;*_ 1) y \ \•\
\ \ 1 1 \ 1 / / / I IAppro�ImaFe>, spate of r' rbdn4 J . TP -2 4 1 N \ -\ ,11 p / r„
\ i 1 1 \ \ 1 / / I I 1 N 1 1" 1 1\ • \ r . \ 5P6i,\ \ \ \ _ i "O' d %r / t
\ 1 1> I \ 5aq , 1 1 i �, ti Orin tnnotes to dorm :oho
\ III 1 / I I \ \ I \ J\ - \ A rexs Iy r
\ \ \ I I / ! / / I / o I i \'\60 0 \ I�o l\ \ \ �\ \ \ �` y\1\ \ \I�A6 - oom�yw oe ryetem
1. \ I1 I I I I / / / / ti I i - \ \ \•O \L o m \"�. -1„ --.: \ 2B 171\-9:e''' STATE RP/ FENCE
\ 1 III I / ! . , _, ./1q d 11rte,(4}�j, • \ .� �a� cam.. \ y u� .. � is
O\ \0 •3
\-,1‘H• I I I i / / 1 1 l \\ \ ,h\ .. \• . ? ,is�O� 'I.A \ \ \ \5 1
\ 11 \ \ \ \ \ \ • \ \ \ \ �:� _ .•' I I\\ . \ \ \\ y� _ N89.35'30V
\ \; \\\\\\\ 166.41 \ \\ \ \ \ W812�J\ \ 1T� „anal ''\ \\ 1 1 \•\\ •\ \\\\xA 1 CO - 1 -T- — t�J127
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•
\\\,\�\\\\\�\�\\\ \\ \\ \1 1 \I \ \\ •i i Nog -35.30,, \\ •\\'�0�\\\\I I`\ \ \1\\ \ \ .\� 0A3 ���\ • ;\ \\�
f\ / 1)11\\ I\\\\ \ N. I I \\ I I � I \\ \\ �S t7gr.`;\\. \ \ \\\ � __ • _ _ _ OE SMVS
1 4. -4, 1i2,-, . �,i-\ — -�-_ _ . • - , _L _..---1 •..-L. - _._ - .--4 v s_ \ — — . . Cl RB (�
SP( ' Al Ic Q
CITY PARK
8-206
•
BENCH MARK -E RIM STORM MH
CUL -OE -SAC EL. 209.28
Scab 1". 50'
S89'33.02'E
178.68
LEGEND
Approximate Test Pit location
• Borings performed by others
••••»•••••••• Proposed Interceptor Drains
Based upon Boundary and Contour Survey for
Rodger E. Lacy Sr., by Lund and Associates,
Surveyors, 2-28-95
* Reviseo 3/2V/95- C�
to
0
Site Plan
Rodger E. Lacy Residence
The Galli Group, Inc
13500 Lake Clty Way NE. suite 202
Seethe, WA 98125 (208) 363-8449
Figure 4
1111111111111111 1111111111LL111 W 1111111111l 11TR11111
S 117'10 ST
SCHOOL
fE PONT ROAD • 1L'
S: 156th ST.
s. 162nd St
1
5. 166th SL
• SAMPLE PLOT SPI A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold
Project/Site: Rodger Lacy
Applicant/Owner: Rodger Lacy
Date: 11/3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP1A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase:. Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES NO X Undetermined
Is the soil a Histosol? YES NO X Histic epipedon Present? YES NO X
Is the soil mottled? YES NO X Gleyed? YES NO X
Matrix Color: 10YR 2/2 - 7.5YR 2.5/1
Comments: Saturated, silty loam w/sulfidic odor
Mottle Colors: None
HYDROLOGY
Is the ground surface inundated? YES NO X Surface water depth:
Is the soil saturated? YES NO X
Depth to free-standing water in pit/soil probe hole? 6.0 "
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones X Water -stained leaves
Water marks
Drift lines
Water -borne sedimental deposits
Additional hydrologic indicators: Sulfidic odor
Surface scoured areas
Wetland drainage patterns
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? >50
Is the hydrophytic vegetation criterion met? YES X NO
Is the hydric soil criterion met? YES X NO
Is the wetland hydrology criterion met? YES X NO
Is the vegetation unit or plot wetland? YES X NO
Reason for jurisdictional decision:
Satisfies mandatory criteria
Field Investigator(s)
Project/Site:
Applicant/Owner:
Vegetation Unit#/Name:
INTERMEDIATE -LEVEL
VEGETATION
Dave Risvold
Rodger Lacy
SAMPLE PLOT SP/A
DATA FORM
ONSITE DETERMINATION METHOD OR
UNIT SAMPLING PROCEDURE
Date: 11/3/94
Rodger Lacy
State: WA County: King
Herb Species
1. Equisetum.sp
2. Athyrium filix-femina
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13. Rubus spectabilis
14. Rubus procerus
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31. Alnus rubra
32.
33
34.
Indicator
Status
FAC
FAC+
FAC+
FACU
Percent Cover Midpointl of Rana
Areal Cover Class Cover Class
15
Trace
• 55
Trace
FAC 100
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints
1. Cover classes (midpoints): T<1% (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
• SAMPLE PLOT SP2A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold Date: 11/3/94
Project/Site: Rodger Lacy
Applicant/Owner: Rodger Lacy
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP2A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES NO X Undetermined
Is the soil a Histosol? YES NO X Histic epipedon Present? YES NO X
Is the soil mottled? YES X NO Gleyed? YES NO X
Matrix Color: 2.5Y 5/1 - 4/1 Mottle Colors: 10YR 4/4
Comments: Mottles and Streaks observed. Saturated, mucky silty loam. Sulfidic odor.
HYDROLOGY
Is the ground surface inundated? YES NO X Surface water depth:
Is the soil saturated? YES X NO
Depth to free-standing water in pit/soil probe hole? 6"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones Water -stained leaves
Water marks Surface scoured areas
Drift lines X Wetland drainage patterns
X Water -borne sedimental deposits Morphological plant adaptations
Additional hydrologic indicators: Observ. of flowing water adj. test hole
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? 100
Is the hydrophytic vegetation criterion met? YES X NO
Is the hydric soil criterion met? YES X NO
Is the wetland hydrology criterion met? YES X NO
Is the vegetation unit or plot wetland? YES X NO
Reason for jurisdictional decision:
Meets requisite criteria
Field Investigator(s)
Project/Site:
Applicant/Owner:
Vegetation Unit#/Name:
Herb Species
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
SAMPLE PLOT
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD
VEGETATION UNIT SAMPLING PROCEDURE
Dave Risvold Date: 11/3/94
SP2A
Rodger Lacy State: WA County: King
Rodger Lacy
Shrub Species
13. Rubus spectabilis
14. Rubus procerus
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31.
32.
33
34.
Indicator Percent Cover Midpointl of Rana -
Status Areal Cover Class Cover Class
FAC+ 100% 7 98.0
FACU 1-5% 1 3.0
2
Sum of Midpoints 101
Dominance Threshold Number Equals 50% X sum of Midpoints 50.5
1. Cover classes (midpoints): T<1 % (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
SAMPLE PLOT SP4A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold Date: 11/3/94
Project/Site: Rodger Lacy
Applicant/Owner: Rodger Lacy
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP4A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS .
Series/Phase: Arents-Alderwood Material •Subgroup2
Is the soil on the hydric soils list? YES NO X Undetermined
Is the soil a Histosol? YES NO X Histic epipedon Present? YES NO X
Is the soil mottled? YES NO X Gleyed? YES NO X
Matrix Color: 10YR 2/1 Mottle Colors:
Comments: Saturated gravelly, sandy loam.
HYDROLOGY
Is the ground surface inundated? YES NO X Surface water depth:
Is the soil saturated? YES X NO
Depth to free-standing water in pit/soil probe hole? <18"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones X Water -stained leaves
Water marks
Drift lines
Water -borne sedimental deposits
Surface scoured areas
Wetland drainage patterns
Morphological plant adaptations
Additional hydrologic indicators: strongly buttressed tree roots
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? 50
Is the hydrophytic vegetation criterion met? YES X see note NO
Is the hydric soil criterion met? YES X NO
Is the wetland hydrology criterion met? YES X NO
Is the vegetation unit or plot wetland? YES X NO
Reason for jurisdictional decision:
Vegetation is presumed to be acting hydrophytically and maple was not rooted in wetland,
therefore, sample point meets technical criteria
Field Investigator(s)
Project/Site:
Applicant/Owner.
Vegetation Unit#/Name:
SAMPLE PLOT
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
VEGETATION UNIT SAMPLING PROCEDURE
Dave Risvold Date: 11/3/94
SP4A
Rodger Lacy State: WA County: King
Rodger Lacy
Herb Species
1. Equisetum.sp
2. Athyrium filix-femina
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13. Rubus spectabilis
14.
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31. Alnus rubra
32. Acer macrophyllum
33
34.
Indicator
Status
FAC
FAC+
Percent
Areal Cover
Trace
Trace.
Cover Midpointl of Rank2
Class Cover Class
FAC+ 100% 7 98.0 *1
FAC
50% 4
FACU 65% 5
38.0 2
63.0 *1
Sum of Midpoints 199
Dominance Threshold Number Equals 50% X sum of Midpoints 98.5
1. Cover classes (midpoints): T<1 % (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
. SAMPLE PLOT SP3A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold
Project/Site: Rodger Lacy
Applicant/Owner.. Rodger Lacy
Date: 11/3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP3A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES
Is the soil a Histosol? YES NO
Is the soil mottled? YES NO
Matrix Color: 10YR 4/1-3/1
NO X Undetermined
X ' Histic epipedon Present? YES NO X
X Gleyed? YES NO X
Mottle Colors: /VA
Comments: No mottles, but streaking was observed. Saturated sandy loam . .
• Is the ground surface inundated? YES
Is the soil saturated? YES
HYDROLOGY
NO X Surface water depth:
X NO
Depth to free-standing water in pit/soil probe hole? <18"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones
Water marks
Drift lines
Water-bome sedimental deposits
Additional hydrologic indicators: Sulfidic odor
Water -stained leaves
Surface scoured areas
Wetland drainage patterns
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? >50%
Is the hydrophytic vegetation criterion met? YES X
Is the hydric soil criterion met?
Is the wetland hydrology criterion met?
Is the vegetation unit or plot wetland?
Reason for jurisdictional decision:
Satisfies technical criteria
YES
YES
YES
X
X.
X
NO
NO
NO
NO
Field Investigator(s)
Project/Site:
Applicant/Owner:
Vegetation Unit#/Name:
INTERMEDIATE -LEVEL
VEGETATION
Dave Risvold
SAMPLE PLOT
DATA FORM
ONSITE DETERMINATION METHOD OR
UNIT SAMPLING PROCEDURE
Date: 11/3/94
Rodger Lacy
Rodger Lacy
SP3A
State: WA County: King
Herb Species
1. Equisetum.sp
2.
3.
4.
5.
6.
7.
8.
9. �-
10. �.
11.
12.
Indicator
Status
FAC
Percent Cover Midpointl of Rank?
Areal Cover Class Cover Class
15%
Shrub Species
13. Rubus spectabilis
14. Rubus procerus
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31. Alnus rubra
32.
33
34.
FAC+
FACU
40%
30% \
FAC 100%
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints
1. Cover classes (midpoints): T<1% (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
• SAMPLE PLOT SP5A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
,:A.(Soils and Hydrology)
Field Investigator(s) Dave Risvold Date: 11/3/94
Project/Site: Rodger Lacy
Applicant/Owner: Rodger Lacy
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP5A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES
Is the soil a Histosol? YES NO X
Is the soil mottled? YES NO X
NO X Undetermined
Histic epipedon Present? YES _
Gleyed? YES NO X
Matrix Color. 2.5Y 4/2 Mottle Colors: NA
Comments: Soils were heavily streaked - sandy clayey loam.
NO X
Is the ground surface inundated? YES
Is the soil saturated? YES
HYDROLOGY
NO X Surface water depth:
X NO
Depth to free-standing water in pit/soil probe hole? 8.0"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones
Water marks
Drift lines
Water -borne sedimental deposits
Additional hydrologic indicators:
Water -stained leaves
Surface scoured areas
Wetland drainage patterns
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC?
Is the hydrophytic vegetation criterion met? YES
Is the hydric soil criterion met? YES
Is the wetland hydrology criterion met? YES
Is the vegetation unit or plot wetland? YES
<50%
Xsee note NO
X
X
X
NO
NO
NO
'Reason for jurisdictional decision:
Vegetation is presumed to be acting hydrophytically and maple was not rooted in wetland,
therefore, sample point meets technical criteria
Field Investigator(s)
Project/Site:
Applicant/Owner:
Vegetation Unit#/Name:
INTERMEDIATE -LEVEL
VEGETATION
Dave Risvold
Rodger Lacy
SAMPLE PLOT SP5A
DATA FORM
ONSITE DETERMINATION METHOD OR
UNIT SAMPLING PROCEDURE
Date: 11/3/94
Rodger Lacy
State: WA County: King
Herb Species
1. Equisetum.sp _.
2. Athyrium filix-femina
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13. Rubus spectabilis
14. Rubus procerus
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31. Acer macrophyllum
32.
33
34.
Indicator
Status
FAC
FAC+
FAC+
FACU
Percent Cover Midpointl of Rank?
Areal Cover Class Cover Class
Trace \
Trace
60%
15%
FACU 100%
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints
\
\
\
\
1. Cover classes (midpoints): T<1 % (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
• SAMPLE PLOT SP6A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
• (Soils and Hydrology)
Field Investigator(s) Dave Risvold - WDI Date: 11/3/94
Project/Site: Rodger Lacy
Applicant/Owner.. Rodger Lacy
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP6A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES
Is the soil a Histosol? YES
Is the soil mottled? • YES
Matrix Color: 10YR 2/1
NO X Undetermined
NO X Histic epipedon Present? YES NO X
NO X Gleyed? YES NO X
Mottle Colors:
Comments: Saturated silty loam
Is the ground surface inundated? YES
Is the soil saturated? YES
HYDROLOGY
NO X Surface water depth:
X NO
Depth to free-standing water in pit/soil probe hole? <18"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones
Water marks
Drift lines
Water -borne sedimental deposits
Additional hydrologic indicators: Sulfidic odor
Water -stained leaves
Surface scoured areas
Wetland drainage pattems
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? 50
Is the hydrophytic vegetation criterion met? YES Xsee note NO
Is the hydric soil criterion met? _ YES X NO
Is the wetland hydrology criterion met? YES X NO
Is the vegetation unit or plot wetland? YES X NO
Reason for jurisdictional decision:
Satisfies technical criteria - vegetation is presumed to be acting hydrophytically
Field Investigator(s)
Project/Site:
Applicant/Owner:
Vegetation Unit#/Name:
SAMPLE PLOT S? 6A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD
VEGETATION UNIT SAMPLING PROCEDURE
Dave Risvold- WDI Date: 11/3/94
Rodger Lacy State: WA County:
Rodger Lacy
King
Herb Species
Indicator Percent Cover Midpoint/ of Rank•
Status Areal Cover Class Cover Class
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13. Rubus spectabilis
14. Rubus procerus
15.
16. \
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24. \
25. \
26. \
27. \
28. \
29. \
30. \
FAC+ 100%
FACU 100%
Tree Species
31.
32.
33
34.
\
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints 1.
1. Cover classes (midpoints): T<1% (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
•
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
• SAMPLE PLOT SP7A
Field Investigator(s) Dave Risvold- WDI
Project/Site: Rodger Lacy
Applicant/Owner: Rodger Lacy
Date: 11/3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP7A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES NO X Undetermined
Is the soil a Histosol? YES NO. X Histic epipedon Present? YES NO X
Is the soil mottled? YES NO X Gleyed? YES NO X
Matrix Color: 2.5Y 4/2-3/2 Mottle Colors:
Comments: Heavily streaked, saturated sandy loam with concretions
HYDROLOGY
Is the ground surface inundated? YES NO X Surface water depth:
Is the soil saturated? YES X NO
Depth to free-standing water in pit/soil probe hole? <18"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones Water -stained leaves
Water marks Surface scoured areas
Drift lines Wetland drainage patterns
Water -borne sedimental deposits Morphological plant adaptations
Additional hydrologic indicators:
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? 100
Is the hydrophytic vegetation criterion met? YES X NO
Is the hydric soil criterion met? YES X NO
Is the wetland hydrology criterion met? YES X NO
Is the vegetation unit or plot wetland? YES X NO
Reason for jurisdictional decision:
Satisfies technical criteria
Field Investigator(s)
Project/Site:
Applicant/Owner.
Vegetation Unit#/Name:
INTERMEDIATE -LEVEL
VEGETATION
Dave Risvold
Rodger Lacy
SAMPLE PLOT
DATA FORM
ONSITE DETERMINATION METHOD OR
UNIT SAMPLING PROCEDURE
Date: 11/3/94
Rodger Lacy
SP7A
State: WA County: King
Herb Species
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Equisetum sp.
Athyrium filix-femina
Glyceria sp.
Shrub Species
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23. Alnus rubra
24.
25.
26.
27.
28.
29.
30.
Tree Species
31.
32.
33
34.
Indicator
Status
FAC
FAC+
FACW+
Percent Cover Midpointl of Rank2
Areal Cove Class Cover Class
15%
5%
35%
FAC 100%
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints
1. Cover classes (midpoints): T<1% (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
• SAMPLE PLOT SP8A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
• (Soils and Hydrology)
Field Investigator(s) Dave Risvold- WDI
Project/Site: Rodger Lacy
Applicant/Owner. Rodger Lacy
Date: 11/3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP8A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES
Is the soil a Histosol? YES NO X Histic epipedon Present?
Is the soil mottled? YES X NO Gleyed? YES _
Matrix Color: 2.5Y 4/3-4/4 Mottle Colors: 7.5YR 3/4
NO X Undetermined
YES NO X
NO X
Comments: compacted road fill material. Concretions were also observed.
Is the ground surface inundated? YES
Is the soil saturated? YES
Depth to free-standing water in pit/soil probe hole?
HYDROLOGY
NO X Surface water depth:
NO X
None
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones
Water marks
Drift lines
Water -borne sedimental deposits
Additional hydrologic indicators: None observed
Water -stained leaves
Surface scoured areas
Wetland drainage patterns
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? see note
Is the hydrophytic vegetation criterion met? . YES see note NO
Is the hydric soil criterion met? YES NO
Is the wetland hydrology criterion met? YES NO
Is the vegetation unit or plot wetland? YES NO
X
X
X
Reason for jurisdictional decision:
Fails technical criteria. Vegetation was dominated by invasive roadway grasses and was not
weighted heavily in the evaluation process.
Field Investigator(s)
Project/Site:
Appli�ant/Owner:
Vegetation Unit#/Name:
INTERMEDIATE -LEVEL
VEGETATION
Dave Risvold
SAMPLE PLOT
DATA FORM
ONSITE DETERMINATION METHOD OR
UNIT SAMPLING PROCEDURE
Date: 11/3/94
Rodger Lacy
Rodger Lacy
SP8A
State: WA County: King
Herb Specie
1. Ranunc tus repens
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31.
32.
Indicator
Status
FACW
Percent
Areal Cover
5%
Cover Midpointl of Rank•
Class Cover Class
33 \
34.
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints
1. Cover classes (midpoints): T<1 % (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0); 1
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until '
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
SAMPLE PLOT SP9A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold
Project/Site: Rodger Lacy
Applicant/Owner.. Rodger Lacy
Date: 11 /3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP9A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents-Alderwood Material Subgroup2
Is the soil on the hydric soils list? YES NO X Undetermined
Is the soil a Histosol? YES NO X Histic epipedon Present? YES NO X
Is the soil mottled? YES X NO Gleyed? YES NO X
Matrix Color: 2.5YR 4/2 Mottle Colors: 10YR 5/8 -strong
Comments: Concretions were also present.
HYDROLOGY
Is the ground surface inundated? YES NO X Surface water depth:
Is the soil saturated? YES X NO
Depth to free-standing water in pit/soil probe hole? <18"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones Water -stained leaves
Water marks Surface scoured areas
Drift lines - 1 Wetland drainage pattems
Water-bome sedimental deposits Morphological plant adaptations
Additional hydrologic indicators: Stream corridor adjacent, uphill of sample point
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? 50
Is the hydrophytic vegetation criterion met? YES Xsee note NO
Is the hydric soil criterion met? YES X NO
Is the wetland hydrology criterion met? YES X NO
Is the vegetation unit or plot wetland? YES X NO
Reason for jurisdictional decision:
Meets technical criteria. Vegetation had been recently cleared/disturbed and was presumed to
be acting hydrophytically
Field Investigator(s)
Project/Site:
Applicant/Owner:
Vegetation Unit#/Name:
SAMPLE PLOT
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD
VEGETATION UNIT SAMPLING PROCEDURE
Dave Risvold - WDI Date: 11/3/94
SP9A
Rodger Lacy State: WA County: King
Rodger Lacy
Herb Species
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species •
13. Rubus procerus
14.
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31. Alnus rubra
32.
33
34.
Indicator
Status
Percent Cover Midpoints of Rank
Areal Cover Class Cover Class
FACU 35%
FAC 50%
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints
1. Cover classes (midpoints): T<1% (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0);5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
•
SAMPLE PLOT SP10A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold
Project/Site: Rodger Lacy
Applicant/Owner: Rodger Lacy
Date: 11/3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP10A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents Alderwood material Subgroup2
Is the soil on the hydric soils list? YES
Is the soil a Histosol? YES NO X Histic epipedon Present?
Is the soil mottled? YES NO X Gleyed? YES _
Matrix Color: 10YR 3/1 Mottle Colors: NA
NO X Undetermined
YES NO X
NO X
Is the ground surface inundated? YES
Is the soil saturated? YES
Depth to free-standing water in pit/soil probe hole?
HYDROLOGY
NO X Surface water depth: NA
X NO
<18"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones
Water marks
Drift lines
Water -borne sedimental deposits
Additional hydrologic. indicators: SULFIDIC ODOR
Water -stained leaves
Surface scoured areas
Wetland drainage pattems
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? 0.0
Is the hydrophytic vegetation criterion met? YES Xsee note NO
Is the hydric soil criterion met? YES X NO
Is the wetland hydrology criterion met? YES X NO
Is the vegetation unit or plot wetland? YES X NO
Reason for jurisdictional decision:
X A. macrophylum was not rooted in wetland. Vegetation was presumed to be acting
hydrophytically, .. Sample Plot met technical criteria
•
Field Investigator(s)
Project/Site:
Applicant/Owner.
Vegetation Unit#/Name:
SAMPLE PLOT
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD
VEGETATION UNIT SAMPLING PROCEDURE
Dave Risvold Date: 11/3/94
SP10A
Rodger Lacy State: WA County: King
Rodger Lacy
Herb Species
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13. Rubus spectabilis
14. Rubus procerus
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Tree Species
31. Acer macrophylum
32.
33
34.
Indicator Percent . Cover Midpointl of Rank2
Status Areal Cover Class Cover Class
FAC+ 40% 4 38.0
FACU 100% 7 98.0
FACU 60% 5
2
1*
63.0 1*
Sum of Midpoints 199
Dominance Threshold Number Equals 50% X sum of Midpoints 99.5
1. Cover classes (midpoints): T<1 % (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
• SAMPLE PLOT SP11A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR.
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold
Project/Site: Rodger Lacy
Applicant/Owner.. Rodger Lacy
Date: 11/3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP11A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents Alderwood material Subgroup2
Is the soil on the hydric soils list? YES
Is the soil a Histosol? YES
Is the soil mottled? YES
Matrix Color. 10YR 2/1
NO X Undetermined
NO X Histic epipedon Present?
NO X Gleyed? YES _
Mottle Colors: NA
Comments: Saturated silty, sandy loam w/sulfidic odor
YES NO X
NO X
Is the ground surface inundated? YES
Is the soil saturated?
YES X
HYDROLOGY
NO X Surface water depth: NA
NO
Depth to free-standing water in pit/soil probe hole? <18"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones
Water marks
Drift lines
Water-bome sedimental deposits
Additional hydrologic indicators: Sulfidic odor
Water -stained leaves
Surface scoured areas
X Wetland drainage patterns
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? >50%
Is the hydrophytic vegetation criterion met? YES X
Is the hydric soil criterion met? YES X
Is the wetland hydrology criterion met? YES X
Is the vegetation unit or plot wetland? YES X
Reason for jurisdictional decision:
Meets technical criteria
NO
NO
NO
NO
Field Investigator(s)
Project/Site:
Applicant/Owner.
Vegetation Unit#/Name:
SAMPLE PLOT
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD
VEGETATION UNIT SAMPLING PROCEDURE
Dave Risvold Date: 11/3/94
. SP11A
Rodger Lacy State: WA County: King
Rodger Lacy
Herb Species
1. Esgisetum.sp
2. Urtica dioica
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13. Rubus procerus
14.
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23.
24.
25.
26.
27.
28.
29.
30.
Indicator Percent Cover Midpointl of Rank2
Status Areal Cover Class Cover Class
FAC 100%
FAC+ 60%
FACU 40%
Tree Species
31. Alnus rubra FAC 60%
32.
33
34.
Sum of Midpoints
Dominance Threshold Number Equals 50% X sum of Midpoints
1. Cover classes (midpoints): T<1 % (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.
. SAMPLE PLOT SP12A
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
COMPREHENSIVE ONSITE DETERMINATION METHOD
(Soils and Hydrology)
Field Investigator(s) Dave Risvold
Project/Site: Rodger Lacy
Applicant/Owner: Rodger Lacy
Date: 11/3/94
State: WA County: King
Intermediate -level Onsite Method X
Comprehensive Onsite Determination Method
Transect # Plot # SP12A
Vegetation Unit#/Name:
Sample # within Veg. Unit:
SOILS
Series/Phase: Arents Alderwood material Subgroup2
Is the soil on the hydric soils list? YES
Is the soil a Histosol? YES
Is the soil mottled? YES X
Matrix Color: 2.5Y 5/2-4/2
NO X Undetermined
NO X Histic epipedon Present?
NO Gleyed? YES _
Mottle Colors: 10YR 4/6
Comments: Presence of concretions was noted
YES NO
NO X
Is the ground surface inundated? YES
Is the soil saturated? YES
Depth to free-standing water in pit/soil probe hole?
HYDROLOGY
X NO
X NO
surface
Surface water depth: 3"-6"
Mark other field indicators of surface inundation or soil saturation below:
Oxidized root zones
Water marks
Drift lines
Water -borne sedimental deposits
Additional hydrologic indicators:
Water -stained leaves
Surface scoured areas
X Wetland drainage patterns
Morphological plant adaptations
Comments:
Percent of dominant species that are OBL,FACW and/or FAC? 50
Is the hydrophytic vegetation criterion met? YES Xsee notes NO
Is the hydric soil criterion met? YES X
Is the wetland hydrology criterion met? YES X
Is the vegetation unit or plot wetland? YES X
NO
NO
NO
Reason for jurisdictional decision:
A. Macrophyllum was not rooted in wetland and was not weighted as heavily as other vegetation.
As such, vegetation was presumed to be acting hydrophytically and Sample Point meets technical
criteria
Field Investigator(s)
Project/Site:
Applicant/Owner:
Vegetation Unit#/Name:
•
SAMPLE PLOT
DATA FORM
INTERMEDIATE -LEVEL ONSITE DETERMINATION METHOD OR
VEGETATION UNIT SAMPLING PROCEDURE
Dave Risvold Date: 11/3/94
SP12A
Rodger Lacy State: WA County:
Rodger Lacy
King
Herb Species
1. Equisetum.sp
2. Glyceria.sp
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Shrub Species
13. Rubus procerus
14.
15.
16.
17.
18.
19.
20.
21.
22.
Sapling Species
23. Alnus rubra
24.
25.
26.
27.
28.
29.
30.
Tree Species
31.
32.
33
34.
Indicator
Status
FAC
Percent
Areal Cover
5%
Cover
Class
1
FACW+ 15% 2
Midpointl of Rana
Cover Class
3.0 2
10.5 1
FACU 50% 4 38.0 1
FAC
60% 5
63.0 1*
Acer macrophyllum FACU 90% 6 85.5 1*
Sum of Midpoints 200
Dominance Threshold Number Equals 50% X sum of Midpoints 100
1. Cover classes (midpoints): T<1% (none); 1 = 1-5 % (3.0); 2 = 6-15% (10.5); 3 = 16-25% (20.5); 4 = 26-50% (38.0); 5=51-75% (63.0);
6 =76-95% (85.5); 7= 96-100% (98.0).
2. To determine the dominants, first rank the species by their midpoints. Then cumulatively sum the midpoints of the ranked species until
50% of the total for all species midpoints is immediately exceeded. All species contributing to that cumulative total (the dominance threshold number) plus any
additional species having 20% of the total midpoint value should be considered dominants and marked with an asterisk.