Loading...
HomeMy WebLinkAboutSEPA EPIC-181-82 - SCHNEIDER NILSEN DEVELOPMENT - SOUTHCENTER PLAZA IISCH \EIDER NILSEN DEVELOPMENT SOUTHCENTER PLAZA II S 147 ST & INTERURBAN AV S EPIC- 181 -82 CITY OF TUKWILA OFFICE OF COMMUNITY DEVELOPMENT FINAL DECLARATION OF NON - SIGNIFICANCE Description of proposal 63,000 sq ft Office Bldg. Proponent Schneider /Nilsen Dev. Co. Location of Proposal Interurban Ave. @ S. 147th St. Lead Agency City of Tukwila File No. EPIC- 181 -82 This proposal has been determined to MEOW/not have).. a significant adverse impact upon the environment. An EIS (1 /is not) required under RCW 43.21C.030(2)(c). This decision was made after review by the lead agency of a completed environmental checklist and other information on file with the lead agency. Responsible Official Brad Collins Position /Title it Planning Director Date COMMENTS: Signature . �. THRESHOLD DETERMINATION Schneider /Nilsen Office Plaza I:I INTRODUCTION The proposed project is .a three -story office building of 63,000 sq. ft. with . related parking on the west side of Interurban Avenue at approximately S. 147th Street. The project will be built in a single phase and will incorporate a portion of Tukwila Recreational Trail #1. DISCUSSION A- pr- eliminary.environmental assessment for this project was conducted in the context of an application for rezoning of the westerly portion of the site. After review of the agency, conimentst - received, .a Declaration of .Non- Significance for the legislative act of.rezone was granted on 22 January 1981. The checklist and the project description under review at .this .tinie are identical to that which was received earlier_.- We have also received since then a detailed structural, hydraulic and utility. evaluation via the Public Works Department and %Building Division indicating' that no unusual technical impacts are anticipated in the construction of this project. The project site was rezoned in its entirety to a C -2 classification upon passage of the new zoning code.text and .map. :The project may be seen, then, as one of an "infilling" nature, consistent with the emerging pattern of redevelopment in the Interurban Corridor Area. We conclude, therefore, that the project will not produce adverse impacts not already anticipated and addressed in the Comprehen- sive Land Use Plan, and that a Declaration of Non - Significance is justified. • • litA? "Ma 10 3 .:1T0 3y Two 51 44s, ARRows .1300\1 B4RA ?Litts.D ALJC Te:, .3.(pric2c0) ccrY oF IL oe 14PFRoof.L._ ts• t '11. fi 1 7! I II I 1111 / 4 • 1 ' • : • I ° r La: • ***--- ti 0(4y/ / /..-_,.. ,---„,--_- \,....,,,,, .._:_,... 4, t 1' MO 06 118e. 1 1 I 111 1 1 I 111 i• • ; TJA2 E. - wea.41•4:, !R-Ei • ,r1 'J1 1 1 — .. 1 0" w f. TPA? TRAIL . •-). I • 6 1••••' r- • City of Tukwila 6200 Southcenter Boulevard Tukwila Washington 98188 Frank Todd, Mayor MEMORANDUM To: Mark Caughey, Associate Planner F ROM: Phillip R. Fraser, Senior Engineer DATE: 5/26/82 SUBJECT: Southcenter Plaza I I Per the attached plan L -1, the Public Works Department has the following comment: we request atithis time a resubmittal of the plan via the Planning Department in such a manner as that the sidewalk fronting Interurban Avenue South conforms to the Standard Plan for sidewalk construction and that the sidewalk is provided and shown to be pro- vided in the public right -of -way or on easements to be given to the City at the completion of its construction. It is anticipated that the final configuration of the sidewalk fronting Interurban Avenue South will be provided in your utility site plans which we anticipate submittal of in the near future. I understand your office will transmit this information back to the developer and his representatives. xc: Tukwila Maintenance Shops Attachment (1) cc.. A 1 ?I�pcv-, cuutto[r�A�Jzi1� City of Tukwi .. 6200 Southcenter Boulevard Tukwila Washington 98188 PLANNING DEPARTMENT TRANSMITTAL DATE OF TRANSMITTAL-' ':;IA / Jai / TO: ;...,` BUILDING 'DEPT.' ❑ POLICE DEPT. ❑ RECREATION DEPT. ' PUBLIC: WORKS. DEPT. �t1.1F_1 DE(L ,et]RT ,i•( ,smE. ' The '_'above;menti.one&applicant has 'submitted for: the. above -reference- project: v.yi a'r vironmental Checkl State - Yent Site /Development Plans U Rezone Request horeline Permit Appl.ication0 Variance Request'' • Conditional Use Permit ❑Other: = " • Applicaiiion the, following Plans or materials Preliminary Pia ❑ Final Plat The attached materials are sent to you for your review and comment. The Planning Dept. needs your comments to satisfy review procedures and to complete the project file. Please use the space provided below for your comments or attach a separate sheet. - Requested response date: 2f / 3L / Review Department comments:' Rv• /-(,/ Date: /5, /9// City of.Tuk 6200 Southcenter Boulevard Tukwila Washington 98188 PLANNING DEPARTMENT TRANSMITTAL i DATE OF TRANSMITTAL 14 / J1 / S I TO:. ❑ BUILDING DEPT:` vi ronmental- `Checklist -; EnV:ironmental Impact. State- •ment°':-' -` Site /Development Plans U Rezone Request Shoreline Permit Application❑ Variance Request El Conditional _ Use Permit ❑ Other: Appl,icati:on The attached materials are sent to you for your review, and comment. The Planning Dept. needs your comments to satisfy review procedures and to complete the project file. - Please use the space provided below for your comments or attach a separate sheet. Requested response date: 21 / LPN / 5 Review Department comments: f es.7; o.: / / ii n r1I--e K Jr .te ..�./� f� l f'Ps eJt � yf hCir P ✓ -e .-. ca-- / —f.� 6�l/-7< 1l[e rrC:L�% Si 7c Jw/ �� �rnJ. f: � �//1 A• , /L�s'�- 7/ -`�2/ ��-�.l i / t.f jy, �!-7 r- w i / 1//-!=›- t■ c - 1-fl l ot-t S c c 1 rr 4X ..i �' �!' C j 7' ate- — cj i 4 .r� i •"-e C- c-+ - ✓ c% L--'— By: �� —�%�� .--�- Date: PLANNING DEPARTMENT RANSMI- TTAL" T0:" U BUILDING DEPT. ZPOLICE DEPT- ❑ FIRE DEPT. . ❑ RECREATION DEPT.' PUBLIC WORKS DEPT. PROJECT: LOCATION: The above mentioned applicant has submitted for the above reference project:_'. environmental Checklist . ❑Preliminary Plat Impact State- ❑Final Plat:: ment Site /Development Plans ❑Rezone Request Shoreline Permit Applicationo Variance Request Use Permit ❑Other: Application The attached materials ire sent to you for your review and comment. The Planning Dept. needs your comments to satisfy review procedures and to complete the project file.' Please use the space provided below for your comments or attach `a separate sheet. Requested response date: - Z / JJ / si Review Department comments: (� P ����S S unity 4-u-n) 1 1 Y I Pyi-u tD r 17 K..&. J SQjn A-5, 4-o V'{-d. CeCDw�w.t:t�XP1� ; �t •►</��k 'b , o.: ra A\ ..,. ce s s 4-0 rYlpf+r��a ts' 4 �-�e! 15 �vevA� hu.r•.%re.� �rr-� Snut D l 5.o tti� o- ■ 6 the following plans or materials - -�- -�I 5 w -.cA\ in s iJ r R v• Date: /-t/-8/ c. PLANNING DEPARTMENT TRANSM1.,T;T_AL:: fir. -r�z•- . i. ;.• POLICE D FIRE v!EPT 'F- , LR UBhC. WOKS,DEPT: r,- e "aboverTmenti oned _-appl i cant has submi tte rF-the.jabo,e...refer,-ence ; pro ect- • •+: .:..n`_'. F, M1:•,�� =i; sir • _'cl,"ti}�:t•.:�i:`:`.<' nvironmenta r .L; Environmental mentw' x . Site /DevelopmentrPlan .St ore7. ine Permit _•Appli Ceti on Conditi onal'`Use 'fermi App]icai,ipn : The attached materials are ,sent: t0;you;for'your' review and - comment:".' The' Planning Dept. needs your comments to satisfy review procedures and to complete the project- file. Please use the space provided below for your comments or attach a separate sheet. Requested response date: 2.1 /- JAM X11 Review Department comments: f) - u o c). 2003 0 Ft au F+zo u i7 s • (1) Sill -i Er2i-1-r'r • OfJ 00 kJ'K.iSTL r1' o G2. elv, l,� fJ �'c��fz,- 1 � pF t r ► rill)!J o':i -SITE tZ6•2rz.L) Bv: Date: 010"10E MEMO CITY of TUKWILA TO: 5G I Nit DER NI tisEN Ptv, FROM: DATE: if., /A.6.`1- SUBJECT: Gµ -141IST sv 6µT p 'fits Q . t S Mkt✓ rciA.t∎,U 106 t U eoNt - j rt e,<SC- f.rsol -vE n2oVtpr 460- FR" Z) tt7 A{J4100 or &,:-cis5' M)P t.tts PAS s-,u� p ot�t p 2 . CITY OF TUKWILA ENVIRONMENTAL CHECKLIST FORM This questionnaire must be completed and submitted with the application for permit. This questionnaire must be completed by all persons applying for a permit from the City of Tukwila, unless it is determined by the Responsible Official that the permit is exempt or unless the applicant and Responsible Official previously agree an Environmental Impact Statement needs to be completed. A fee of $50.00 must accompany the filling of the Environment `+ 4m@ma to cover costs of the threshold determination. I. BACKGROUND I. Name of Proponent: Schneider Nilsen Develo•ment 2. Address and Phone Number of Proponent: _ •1I Tukwila, Washington 98168 Telephone: 243 -9960 3. Date Checklist Submitted: May 5, 1982 4. Agency Requiring Checklist: Planning 5. Name of Proposal, if applicable: p_. 6. Nature and Brief Description of the Proposal (including but not limited to its size, general design elements, and other factors that will give an accurate understanding of its scope and nature): SPP Arta-hod za II) 7. Location of Proposal (describe the physical setting of the proposal, as well as the extent of the land area affected by any environmental im- pacts, including any other information needed to give an accurate under- standing of the environmental setting of the proposal): See attached 8. Estimated Date for Completion of the Proposal: October 1982 9. List of all Permits, Licenses or Government Approvals Required for the Proposal (federal, state and local): (a) Rezone, conditional use, shoreline permit, etc. (b) King County Hydraulics Permit (c) Building permit YES NO x YES NO x YES x NO Puget Sound Air Pollution Control Permit Sewer hook up permit Sign permit, Water hook up permit Storm water system permit Curb cut permit- Electrical permit (State of Washington) Plumbing permit (King County) Other: 210115a11T101.1 ,, F -11x. ‘ALA TRAIL #1 YES NQ YES X NO YES X NO YES X NO y6)( NO YES X NO ,YES %_ NO YES %( NO 10. Do you have any plans: for future additions, expansion', or futh,eractivity related to or connected with this proposal? If yes, explaini;f:``? No 11. Do you know of any plans by others which may affect the property covered by your proposal? If yes, explain: No 1'2. Attach any other application form that has been completed regarding the pro- posal; if none has been completed, but is gxpected to be filed at some futur, date, describe the nature of such application form: II. ENVIRONMENTAL IMPACTS (Explanations of all "yes" and "maybe" answers are required) YES .MAYBE NO • 1. Earth. Will the proposal result in: (a) Unstable earth conditions or in changes in geologic substructures? _ (b) Disruptions, displacements, compaction or overcover- ing of the soil? iC (c) Change in topography or ground surface relief fea- tures? (d) The destruction, covering or modification of any unique geologic or physical features? -2- (e) Any increase in wind or water erosion of soils, either on or, off the site? (f) Changes in deposition or erosion of beach sands, or changes in siltation, deposition or erosion which may modify the channel of a river or stream or the bed of the ocean or any bay, inlet or lake? Explanation: 2. Air. Will the proposal result in: (a) Air emissions or deterioration of ambient air quality? (b) The creation of objectionable odors? (c) Alteration of air movement, moisture or temperature, or any change in climate, either locally or regionally? Explanation: 3. Water. Will the proposal result in: (a) Changes in currents, or the course or direction of water movements, in either marine or fresh waters? (b) Changes in absorption rates, drainage patterns, or the rate and amount of surface water runoff? (c) Alterations to the course or flow of flood waters? (d) Change in the amount of surface water in any water ,body? (e) Discharge into surface waters, or in any alteration of surface water quality, including but not limited to temperature, dissolved oxygen or turbidity? (f) Alteration of the direction or rate of flow of ground waters? (g) Change in the quantity of ground waters, either through direct additions or withdrawals, or through interception of an aquifer by cuts or excavations? YES MAYBE NO X x -3- _x_ X (h) Deterioration in ground water quality, either through direct injection, or through the seepage of leachate, phosphates, detergents, waterborne virus or - bacteria, or other substances into the ground waters? (i) Reduction in the amount of water otherwise avail- able for public water supplies? • Explanation: 4; Flora. Will the proposal result in: (a) Change in the diversity of species, or numbers of any species of flora (including trees, shrubs, grass, crops, microflora and aquatic plants)? (b) Reduction of the numbers of any unique, rare or endangered species of flora? (c) Introduction of new species of flora into'an area or in a barrier to the normal replenishment of existing species? (d) Reduction in acreage of any agricultural crop? Explanation: 5. Fauna. Will the proposal result in: .(a) Changes in the diversity of species, or numbers of any species of fauna (birds, land animals including reptiles, fish and shellfish, benthic organisms, insects or microfauna)? (b) Reduction of the numbers of any unique, rare or endangered species of fauna? (c) Introduction of new species of fauna into an area, or result in a barrier, to the migration or movement of fauna? (d) Deterioration to existing fish or wildlife habitat? Explanation: YES MAYBE NO 6. Noise.. Will the proposal increase existing noise levels? Explanation: 7. Light and Glare. Will the proposal produce new light or glare? Explanation: 8. Land Use. Will the proposal result in the altera- tion of the present or planned land use of an area? Explanation: 9. Natural Resources. Will the proposal result in: (a) Increase in the rate of use of any natural resources? (b) Depletion of any nonrenewable natural resource? Explanation: 10. Risk of Upset. Does the proposal involve a risk of an explosion or the release of hazardous substances (including, but not limited to, oil, pesticides, chemicals or.radi- ation) in the event of an accident or upset conditions? Explanation: YES MAYBE NO _x_ 11. Population. Explanation: • • Will the proposal alter the location, distribution, density, or growth rate of the human population of an area? 12. Housing. Will the proposal affect existing housing, or create a demand for additional housing? Explanation: 13. Transportation /Circulation. Will the proposal result in: (a) Generation of additional vehicular movement? (b) Effects on existing parking facilities, or demand for new parking? (c) Impact upon existing transportation systems? (d) Alterations to present patterns of circulation or movement of people and /or goods? (e) Alterations to waterborne, rail or ail'' traffic? (f) Increase in traffic hazards to motor vehicles, bicyclists or pedestrians? Explanation: 14. Public Services. Will the proposal have an effect upon, 1 or result in a need for new or altered governmental services in any of the following areas: (a) Fire protection? (b) Police protection? (c) Schools? (d) Parks or other recreational facilities? (e) - Maintenance of public facilities, including roads? -6- YES MAYBE NO x (f) Other governmental services? Explanation: 15. Energy. Will the proposal result in: (a) Use of substantial amounts of fuel or energy? (b) Demand upon existing sources of energy, or require the development of new sources of energy? Explanation: 16. Utilities. Will the proposal result in a need for new systems, or alterations to the following utilities: (a) Power or natural gas? (b) Communications systems? (c) Water? (d) Sewer or septic tanks? (e) Storm water drainage? (f). Solid waste and disposal? Explanation: 17. Human Health. Will the proposal result in the crea- tion of any health hazard or potential health hazard (excluding mental health)? Explanation: -7- YES MAYBE NO x X X • • 18. Aesthetics. Will the proposal result in the obstruc- tion of any scenic vista or view open to . the public, or will the proposal result in the creation of an aesthetically of- fensive site open to public view? Explanation: 19. Recreation. Will the proposal result in an impact upon the quality or quantity of exist- ing recreational opportunities? Explanation: 20. Archeological /Histroical. Will the proposal result in an alteration of a signifi- cant archeological or his - torical site, structure, object or building? Explanation: YES MAYBE NO CERTIFICATION BY APPLICANT: I, the undersigned, state that to the best of my knowledge the above information is true and complete. It is understood that the lead agency . may withdraw any declaration of non - significance that it might issue in reliance upon this checklist should there be any willful misrepresentation or wi ck of full disclosure on my part. /l�r, -� 6//0/82, Z Signature and Title Date X CITY OF TUKWILA ENVIRONMENTAL CHECKLIST FORM Attachment I. BACKGROUND 6 An office building with 63,012 gross square feet, ap- proximately 57,346 net leasable area. 212 parking spaces are provided. The building is 38.4 feet high. 226.0 feet in length and 100 feet wide at the widest point on two floors. The exterior of the building is steel fram- ed waterproof gypsum board with 3 constucco, painted a light earthen tone and solar bronze insulated,.anolize`d, aluminum ribbon glass. 7. The building will be located with the long access fronting on Interurban Ave. S. The minimum setback from the centerline of the street will be 50 feet with the majority of the building setback 62 feet from the centerline of Interurban Ave. S. The building sideyard and rearyard separations to the nearest R -Zone not including the subject parcel is 80 feet. The site is approxi- mately 3.8 acres of which approximately 90% will be affected by this proposal. The site is bisected by S. 147th St. (Tukwila Trail #1) The site is essentially flat sloping northeast to southwest from an elevation of 20.00 to 30.00' in approximately 250' (Approx. 4 %). From the 30.00' elevation to the parcel bolandaries a uniform slope of approximately 25% is encountered. This steep slope area represents only 16% of the total site area. II. ENVIRONMENTAL IMPACTS 1.(b) There will be an approximate cut of 1900 cu. yards of material. most of which will be suitable for fill on other portions of the site. Approximately, 4,000 yards of material will be imported to•the site. Compactions under building footings will be likely. 1.(c) Cuts and fills over the site will result in a parking lot surface of approximately 6% slope, compared to 4% existing slope. Some cuts will be required at the southwest parking lot borders. The soils report prepared by Shannon & Wilson, Inc. Oct. 1978 revealed that unstable slope conditions exist on the slopes on either side of an existing drainage course at the west end of the site. It is the owner's intention to have additional field . explorations in this area for the purpose of evaluating existing'slope conditions and developing stabilization schemes. • 2.(a') Additional vehicular traffic will occur on Interurban Ave. as a result of this project. However, office uses normally result in just over two trips per day per vehicle; and the pollutants emitted into the air as a result of this project probably would have an unmeasurable effect on therm bient air quality in this area, where there is not a highly intensive retail or office use. 2.(b) Automobile exhaust should have little effect on exhaust odors which may presently exist as a result of traffic on Interurban Ave. 3.(b) An existing drainage course exists entering at the West Property Line and eventually finding its way to Interurban Ave. Some of this runoff purculates into the site saturating the soil where parking is planned in this proposal.. We propose to provide an improved sub - grade drainage course to Interurban Ave., thus improving the soil stability and unavoidably increasing the amount of surface water runoff to Interurban Ave. See 3.(13) below. 3.(d) See 3(b) above. The additional water runoff would seem not to be significant. 3.(e) The water entering the existing system is at times heavily silt laden due to erosion to the west of the subject property and also across'the site. The top two to five feet is a mixture of organics and clay. (See attached soils reports).. We would propose a manhole structure- which would intercept water runoff from adjacent properties to the west and by means of a subgrade CMP deliver that runoff to Interurban Ave. The quality of water entering the system in Interurban would thus be improved, due to the beneficial settling which would normally occur at the manhole structure. A storm detention facility will be • provided for pervious and impervious surfaces on the site. Water entering the storm system from this facility would be of a higher temp. than normal due to the effect of warm asphalt. 3.(g) The groundwater table on the site may be affected. By intercepting water runoff entering the site from the west it is expected that the site will "dry out" from its present state. 3*.(i) Office use will not have a high demand for water resources. Water usage in the building will be limited to operation of toilet facilities, irrigation for landscaping, and building fire protection systems. 4.(a) Landscaping is an integral part of the proposal. Decorative shrubs, evergreen shrubs and trees are planned both as noise buffers to traffic noise and as sight screening for parking lots. See Landscape Plan attached. Page Three • 5.(a) The existing swampy area is a nesting bed for insects and aquatic organisms. Presumably their numbers would decrease with the development of the project. The site is not a significant habitat for any species of birds or land animals. The addition of new flora in the area would have a positive impact on the environment in that it would attract species of birds which are attracted to particular species of flora. 6. The addition of more automobiles will increase noise levels on Interurban Ave., however, because the project is located in the foreground of a steep slope. Residential areas to the west will not be appreciably affected by this proposal. 7. Glare from parking lot lights will be minimized through the use of parabolic lens equipped fixtures. 8. The west 150' of the . site is presently zoned C -2 with the remainder of the site zoned c-1 We propose to locate the.building within the existing C -2 zone meeting all setback requirements including rear - yard to an C -1 zone. 9.(a) Additional water resources will be required to service the building. 11 It is difficult to ascertain whether population increases in an area are the result of speculative office development or whether influxes of population into an area creates a demand for such development. 12. Demands for additional housing in the area may be created due to the trend to cut commuting time in the interest of conserving fuel. 13.(a) Additional traffic on Interurban Ave. will result from this project. 13.(c) The proposal may result in increased ridership on existing bus routes. 14.(a) The project will be sprinklered. 14.(b) The project may put some demands on existing police services although office buildings would not normally require unusual security measures. 15.(a) The new building will be made to conform to the state energy code and will have a hydronic heat recovery HNAC system. 16.(a) Additional power transformers may be required for the project. 16.(d) An existing 8" sanitary sewer is presumed to be adequate for this project. 16.(e) Alterations to the existing drainage course would have positive environmental impacts. (See 3(b) and 3(e).) TheRichalSmithCompany CONSULTING ENGINEERS 600 Colman Building Seattle, Washington 98104 (206) 6248150 May 10, 1982 1� City of Tukwila 6230 Southcenter Boulevard Tukwila, Washington 98188 Attention: Al Pieper RE: PLAN REVIEW #82 -T -03 Gentlemen: RECEIVED CITY OF TUKWILA MAY 121982 BUILDING DEPT. We have received plans for the proposed Plaza One Office Building and have reviewed them for compliance with Chapters 23 - :'29of the Uniform Building Code. .Our comments follow: 1. Provide a soils report. 2. Concrete cover as specified in structural notes is incorrect per : UBC Section 2607(0) . (Refer Detail 2/S -1.) 3. Special inspection is required for A -325 bolts per UBC Section 306(a) 5. 4. Indicate spacing, edge and end distances for all bolted connections. 5. Roof Plan on Sheet S -4 and Roof Plan on Sheet 7 appear to be in disagreement over skylight locations between Grids 7 and 8. Clarify discrepancy. 6. Clarify wing wall construction at entries and indicate connection to concrete retaining wall at Detail 5/S -1. 7. Stair fabrication drawings are to be submitted to the City of Tukwila for approval prior to fabrication. Provide lateral load path analysis and calculations verifying conformance with UBC Section .2312. Please return for our review when the above questions have been answered. Please call if you have any questions. Sincerely, THE RICHAL SMITH COMPANY. By: Jay Taylor cc: Schneider /Nilsen, Developers, 14900 Interurban Ave. S., Tukwila, Washington W- 3471 -01 SHANNON & WILSON, INC. Geotechnical Consultants 1105 North 38th Street• Seattle, Washington 98103•Telephone: (206) 632 -8020 • Cable: GEOSAW October 27, 1978 G.A.M. Construction 16625 Redmond Way Court Building Redmond, WA 98052 Attn: Mr. Gary Nilsen • CONSULTING SERVICES, PARCELS I & II, INTERURBAN AVENUE & SOUTH 147TH STREET, TUKWILA, WA. Gentlemen: At your request on October 2, 1978, we have reviewed our report titled "Soil Investigation, Proposed Industrial Site, Interurban Ave. at South 146th Street, Tukwila, Washington," dated September 17, 1963, and a Cascade Testing Laboratory, Inc.`s report, titled "Soils Investigation, Parcels I, II & III, Interurban Ave. & South 147th Street, Tukwila, Wash- ington," dated. August 18, 1978. The purpose of reviewing these reports was to assist you in determining the feasibility of the proposed development. This letter report presents the results of our review of the reports along with our recommendations. PROJECT DESCRIPTION It is our understanding that you have an option for developing the property into an office complex. The proposed structures would consist of moderately loaded two (2) story buildings. The building location is restricted to an area within 150 feet from Interurban Avenue as indicated on Figure 1. EXISTING CONDITIONS We understand that the major portion of each parcel is relatively flat and covered with grass, but the portions adjoining the west property lines slope uphill at estimated inclinations between about 1V on 5H and 1V on 1.2H, as shown on Figure 2. Some apartment complex has been constructed upslope from the William L. Shannon, P.E. • Stanley D. Wilson, P.E. (consultant) Earl A. Sibley, P.E. • Walter L. Wright, P.E. • Raymond P. Miller, P.E. • Sigmund D. Schwarz, P.G. • David E. Hilts, P.E. • Derek H. Corntorlh, P.E. M. Mike Allzadeh, P.E. • Rohn D. Abbott, P.E. • Robert J. Deacon, P.G. • George Yamane, P.E. • Maurice D. Veatch, P.G. Seattle • Spokane • Portland • San Francisco • Fairbanks • St. Louis G.A.M. Construction Attn: Mr. Gary Nilsen October 27, 1978 Page 2 W- 3471 -01. property. Several landslides have occurred at some distances west of the west property lines. SUBSURFACE CONDITIONS Two borings, designated DH -1 and DH -2, were accomplished in 1963. They were located on the sloping ground in the western portion of Parcel I as shown on Figure 2. Logs of these borings are . presented on Figure 3. In the upper five feet of DH -1 and DH -2, a medium .stiff, silty CLAY and clayey SILT with sand and gravel was encountered. This material was believed to be partly a highly weathered residual soil, similar to the weathered rock and soil encountered at higher elevation along the slopes. It is also possible that some of the material was'slope wash and fill. This upper material was under- lain by another medium stiff clayey SILT and silty CLAY with some zones of silty sand and gravel. This material may have been formed from siltstones, sandstones and shales by the process of weathering. • In DH -1, yellow oxidized zones were encountered between the depths of 5 and 9.5 feet. Below 9.5 feet the material was primarily a glacially- overridden, hard, slightly clayey SILT with unconfined compressive strengths in excess of 4.5 tsf. In DH -2, the soils encountered in the entire boring depth of 28.5 feet were more deeply weathered. Oxidized yellow zones occurred within the silty CLAY, SAND and GRAVEL to a depth of about 17 feet. Most of these materials were classified as medium to stiff. . .In 1978, two borings, designated TB -1 and TB -2, were drilled by others in the eastern portion of Parcels I and II, as shown on Figure 1. Logs of these two borings are presented on Figures 4 an4 5. Fill or Slope Debris, consisting of medium dense, sandy, gravelly, decomposed CLAYSTONE with charcoal fragments and organics, was encountered in the upper 7 feet of TB -1 and TB -2. In TB -1, the upper debris was underlain by medium stiff SILT with scattered roots and organics to a depth of about 23 feet. A loose, silty SAND layer with organics was encountered between the depths of 13 and'14 feet. Below 23 feet medium stiff to stiff CLAY and weathered CLAYSTONE with organics and wood fragments were encountered. These materials were underlain by stiff, weathered SILTSTONE and CLAYSTONE to the bottom of boring at 34.5 feet. G.A.M. Construction Attn: Mr. Gary Nilsen October- 27, 1978 Page 3 W- 3471 -01 In TB -2, the upper 7 -foot debris was underlain by a one -foot layer of very soft organic SILT, followed by a soft SILT with roots to a depth of 12 feet. A medium stiff, organic SILT and silty PEAT with a large piece of wood was encountered between the depths of 12 and 18 feet. Underlying the organic and peaty soils was loose to medium dense, silty SAND with scattered organics to a depth of 26 feet. Below this depth was a very dense fine SAND (Weathered Sandstone). GROUNDWATER CONDITIONS During the field exploration period in 1963, groundwater was not encountered in either Boring DH -1 or DH -2, although there were a few local wet zones in DH -2. The slopes and exposures to the north and south of Parcel I were also dry. However, the 1978 explorations indicated that the site appeared'to be wet much of the year. Shrinkage cracks of one inch was observed over much of the site. Where a ravine entered the center of Parcel I, water flowed from beneath the slope debris at a.point approximately 3.0 feet east of the west property line. Samples became wet at about 8 feet below the ground in Borings TB -1 and TB -2, but ground- water levels were not measured. CONCLUSIONS AND RECOMMENDATIONS Slope Stability The 1963 soils report recommended that the excavation slopes to the north and south of Parcel I be not greater than 1V on 1H and the excavation slope to the rear or.wezt of..the:.site be no steeper than 1V on 1.5H provided an asphalt lined drainage ditch was properly installed to intercept surface water and prevent erosion of the cut slopes. The 1978 soils report revealed that evidence of unstable slope conditions was observed along the western excavation slope. We, therefore, recommend that additional field explorations and stability analyses be performed for the purpose of evaluating the existing slope conditions and developing stabilization schemes, if desired. Foundation Su•port Because of the existence of organic and peaty soils and the low consistency of the rather thick compressible subsoils, con- ventional footings would-not be suitable for supporting moderately loaded structures unless the site is properly preloaded. If time G.A.M. Construction Attn: Mr. Gary Nilsen October 27, 1978 Page 4 W- 3471 -01 is allowed, the scheme of preloading the site may be considered. This scheme would require additional field explorations and laboratory testing in order to assist in determining the amount of organic and peaty soils present and estimating the amount of preloading fill and the duration of preloading. In addition to the preloading scheme, pile foundations may also be used for:supporting the proposed structures. We under- stand that you are concerned about the vibration caused by pile driving, because it may reduce the stability of the existing slopes. Thus, auger cast -in -place concrete piles are under consideration. For your preliminary planning purposes, a 14 -inch diameter pile with a minimum penetration of 40 feet in Parcel I and 30 feet in Parcel II was considered. For these piles, a maximum allowable design load of 35 to 40 tons per pile may be used for your preliminary cost estimating purposes. For final design, it will be necessary to drill more borings to better determine the sub- surface conditions so that recommendations for pile design could be developed. Additional borings are particularly necessary for auger -cast piles, because it is difficult to determine the pile lengths fi~am drilling action during auger -cast pile installation.. Floor slabs could be placed on properly prepared subgrade or pile supported, depending upon the loading condition, the grade level, and the results of additional test borings. It is recommended that the settlement of the existing fill be monitored. If settlement of the fill is still occurring, it would have an impact not only on the floor design but also on the design of. piles. Since the project may not start until next spring, this monitoring should be initiated as soon as possible. Drainage System Depending on the final grade elevations, footing drains and under the floor slab drains may be required. Also, all surface water should be properly collected and directed away from the site.. G.A.M. Construction Attn: Mr. Gary Nilsen October 27, 1978 Page 5 We appreciate the opportunity to be of service to you. Sincerely, SHANNON & WILSON, INC. George /-man =/, P.E. Vice Pr-side t JW:ln Encls: Figures 1 thru 5 W- 3471 -01 e io /Z ,5 %V VQ5/7/1 VA/ /AYr7rA/. A i97 T~ (Sr -77)/e\v&/4 \y/216///4 4- /47 =V' ra �r \\ pARCfL \` •.f r • • CASCADE TESTING LABORATORY ENGINEERS 11123 N.E. 21 STREET - BELLEVUE_ WASHINGTON • 98007 GEOLOC 206 • 641 {{CEE�R T. NO I SCALE • ! / =Zcv •u D2/••NN .T • • A DATE /1 *- •.e - ii! t REV. NO. NOt ES PAGE • 00, ocs 0 • 0 0, U (J Is N • A. t ..* ••• ii%rTJ+ir► -:•-, 4 1 I I 1 1 I.1 i t1 ■ interurban Ave. '. i NOTE Contours deAfwnin ed by )and /eye/1.)o. 29 AupsT, /363 SC `C ::ESCe'PT /ON, E-rpcsut-es / / 2 : Yellow - brouwn weathered sandy , jointez S /LTSTCWE - bec.'.n s1/72'y si /ty CLAY /i/, ec.t d rz ina y e di .'44:711 /NDIJSTR!AL S/ TE l/li'TERUP, &4t/ AYE: ,e S_ /46 *_' :..TUK,.-/. A,` WISH. • FiCiF /C PROF L E ER , /M SITE PLAN • `SHANNON & WILSON SOIL MECHANICS 1 EOUNO AMON ENGINEERS DH I £/e v. 2/9 DEPTH DE5CF /PTIO/Y 0 • Med. Stiff brn. e scme'/? ed rc Fire 5i4i . < ana u/a r GP „9 �L teleg cryonics 5 Z1 Me�sfffQgr-7�� c /a�e� S/L iv/ Some SAND 4 2hep J2 r GRAYEZ. Sonic ye //oa, cr'i- dIzed zones Some rid -:3I ua /jointing r”; bedding • Herd gray s /,�fr/i �� c /ay yeti 5 /LT Iv/ zones of or.vi- o /a:':r rre 1� im r 5A/iD f fine GRAVEL. S r1nG th %17 /2,7) a fi:`n WATER CONTENT ex /I 9.5 /85 35.5 STANDARD PE/VI TR. A 1 ON O L/Y..*: :::NF /t /ED CCl4PP, ESS / VE 5 T REN(.77g, s: / . 5 ' 26.4 1.5 /2.0 4-3 _ >4.5 /3.5 71 /3.2 77 70 NOTE Standard per : tr.c tion is shown as Me r u.n&f - . f t ldsc:: re ir_ed to drive • a Z'O.G. s/it soon sa»f, /er one s4 o r 040 M. ham. >.e r, :=D dre/oj LFLEND fI .c /: t spoor, s2:7pie . Figure- to left i:.dica/cs so.rp/� 4unlber 11 2.•O.D. S1ieiby tube samplee t Unconfir7e.d rcn pressi /e srrs.;arh re_:t/ts eS /;Mated by :use ?r e Poc•fe s4 Unconfined c rn/Ore.$irs stren7tn re;i/ts bJ 1_tuczi test . Dh� ELEV.. 2/8' /ED DEPTH CESCR /PT /Oh' S/ Vt.- � fs;- 0 J 6 // /6 26.5 A/e_i sriff ye //,;c. - to 1 J S /,;,h; /r .S ;dy G /Q,,r y 5/i7' Pled. stiff rf er;, D /tee -grad 1-\da ic:l.S7L Tw/so ve SAh�LT Med. Miff 9ra q f ye / %a/ silk/ _AY -4 so" , ' $I/I/D e :z a'ra r fine GRAVEL . fra p; en Is Oar 9ra% 00.7ri.e :o m fcl.air: 54.•YLI u./ scm e. SICici r:L,s:.rneCMY, y 5/Z 7 bi uJer. ;�.e: r 5r; he /1.91,l yieen, big, e -yra yto darkQracy Si, CZ A y w /i »J' e meQ.rof,ie SAND 41 a. ;g'J /ar 6-PAVEL fray ;r en is. • WATER STANDARD UNCONFINED CONTENT PENETRATION COMPRESSIVE eA STRENGTH, ts, 55.0 '5.5. 26.2 1 38.5 oT 7i 8T /cT /2.5 5.. 37.5 37.7 ,/2 P ✓sn ed -2o /O 6 /3 55.7 /2 /NvUSTR /AL 5/ TE /NTERURBA/'/ AVE. ? 5. :'40 TUKWIL A) : WASH. PAC /F /C PROPELLER , /NC. 80R /NG LOGS 0.7'� /.2 0. /. 36 f {/.5 P /. 15 * 10.3 W-63 -2S4 Sept.i5E3 SHANNON & WILSON - /P. C3 SOIL MECHANICS & FOUNDATION ENGINEERS Y STRATA ELEV. - DEPTH STANDARD PENETRATION C. I CORRECTED) BLOWS/ FOOT DESCRIPTION NOTFS Ott 6. /VAI OEA1..5�, • '6-0 An/0 640. m./A/, t..›4/c10Y Y ('o ,STo - /C F7P1 'I EvTS), 08-C 041 P05E0 G L 4 Y . 3 7-0 4 6 : 7 - - \ V i n es G. A,t c a. �, p gGr/1l W 73 (7c c o.P cS L oPE .DEfSR/5) .4,0/57-7 -/0 /IIEO /v ^l ‘577C F- 4QEY ,..5/4-7-- /'1/15_S /vr \v /rli 0 4G/15/o/c/AG /7A/b- Ara'7'6 / V6:1: LoosE.4.re'7; ..s/.1Y Fin /&" 3.4i1/0 %wry occ-is/o v tc v.(014 i/es ..YET. • -zr /IIEO /OA •5P'5; oxo.v'/ - 4 EY A/ti/04 ,qoc+/,J S /GT \\/ /Tii " o.4AA//G' LE't/SES, \vEr — fjEco/(1 /n/4 e2.2 .4 ./ /G 5/4 7— ,!T /5- / \\/ /Tf/ c7 4 5/47"4 4/.. y " F //✓� ,�4/•/0 EDS , \ /el TE.0 R /VF•C 06.0:0S)7"..5 ). Alto/O,41 .577,50; 4�E'� \vN /r ; , ,e. 4NO 4dE eAt Gi. AY wing RD' /.QA /E/t 7 5 oec. C4-47- AAJO So,0 \`/000 (,Sio ' 0E,3e/5 ). 577if v,,cetE Oc 4Y.e0 47-47'Sra.../E So.0 .4' IAic .OrberS TEST BORING LOG Cascade Testing Laboratory, Inc. Engineers - Geologists 14120 N. E. 21st Street. Bellevue. Wash 98037 Phone 641.2573 - - �f, 'CERT. No. • Jo/G5 /// V 5 T /GAT/o/4 //NrC/�f>i/2 i t kg. I j. /47 a ,5 \\/ /L A / \V/•4L5f/ /' 7 AJ BORING NO. / IDWN BY P � _.L OF Z CHKD 5Y ,z/ 4 uJ D STRATA ELEV. - DEPTH STANDARD 'PENETRATION C„ (CORRECTED) BLOWS/ FOOT 0 S0 . ' . DESCRIPTION Srhec, 0 ,f,e />ECAYe o c v6=-- - - e6E.✓, O ‘VAl •r,/' 4-ee Y ix r.7-1),•/&' A o C647',STaA/6:: • 4r = To. j!•S' • i r- • NOTFS . ‘- 5 v /G • TEST BORING LOG i,,irc,<,,), Cascade Testing Laboratory, Inc. -r().- \\// Engineers - Geologists 14120 N E. 21st Street Bellevue. Wash 93007 Phone 641.2573 5 /A/VC 5 T /GAT /oA) ,4 Ay. / j. /4? r i7 /-1' \\//4c.5////1/1-0/4 BORING NO. PAr,E OF { LTE - ~ - may. f CERT NC -�� . ? - DWN sy . JCKD F.: U D STRATA ELEV. - DEPTH STANDARD PENETRATION C. (CORRECTED) BLOWS/ FOOT o so • DESCRIPTION • IWATER I TA fl1 • • .1�_ • • . • • • • .-- • -t o . .5r /,�F AGO /vAI OE'/ Z. EN,SEO , 1..../4././7-4,r• , /./a" ‘SAA/0 4.-.'EY An/O Apo tv../ C44 Y e4,4y,5TdA/E. F.At44.4I[:it/T5 'WO 40.4"//e.5 A10437-. (F /[C o.4- ,56 ,0,0,&-- i.S) . A • ' • Ff •o. ✓A/ 0RG,•.4.ViG ,/G T , 'tVE7 ' r j .50Ft, e' 6" •r' .S /e..T , i11A 5S/VC-5- ,\\//r// OGG.f•5 /OA/AL F/ 6.- .PoOTS , ✓ET. -i AIE0 /0A1 c5T /FF , .4'E7' -A -sea % %JAI , 04044.3/ /G .5 /GT "WO ,5/4 1-7' .FEAT tV/ ray 4 LA.Pa6' . /� /eGg of \ '/OOO .4 7 - /9 �/ kvET. 1 �■■■� • si ��� le •••.• . • • u /1160/041 O b N,SE , 4...1e/e. Fin// (.1.4,1/0 \vim/ y'N '1 — # 'e'0 ..4:1/.✓5 1Ve T; - . ' • :.:. • .: • • • _sf ,IN Iii Leo SC , 4QEY, .5 /GTY FiA/E . ,•,/ ■sir// ' Oee.f S /D.c/ -4 4 o.PG.I.�/ /CS , XV6 T Keer-45 -f7 - Z4 ' -� ,� V/E•PY Ot N.SE, G /GHT 4-•'E Y; F /Aie- 6,1A/0 �.' t) (w THE.PbD �.t/057A/E) • Tp. yo. o' NOTES c.5O /G 3 /A/VC-5 77 6AT /off TEST' BORING LOG /Aii& -,ev,. 4 Aye. / j. Af7T2 57 �lU, _ \�it�� , \VAL3 ///' ' ro-1 Cascade Testing Laboratory, Inc. Engineers - - Geologists BORING NO 14120 N. E. 21st Street Bellevue. Wash 98007 Phone 641.2573 P-s / Oc / DATE e - - 76. ICERT. NO ` -_ .. ;,...- 4DwN :Y f .__ "•: CHKD trf