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SEPA E97-0039 - JOHNSON BRAUND ARCHITECTS - 51ST AVENUE SOUTH OFFICE BUILDING
51STAVE. S. OFFICE BUILDING NEW BUILDING CONSTRUCTION WITH STORAGE & PARKING 15150 51ST AVE. S. E97-0039 AFFIDAVIT OF 1, 1 ��GAN�Mc� lCi ONotice of Public Hearing fl Notice of Public Meeting O Board of Packet O Board of Packet Planning Packet Adjustment Agenda Appeals Agenda Commission Agenda DISTRIBUTION herebydeclare that: O Short Subdivision Agenda Packet O Notice of Application for Shoreline Management Permit 0 Shoreline Management Permit. was 0 Determination of Non- significance 0 Mitigated Determination of Nonsignificance fl Determination of Significance and Scoping Notice O Notice of Action Official Notice Other El Other mailed to each of the following addresses on ,R -j1- X -L C. i Ate, , rwx � La.j TA.; -)w I c -A-98 frA4ed. Name of Project)\ M) 5 162- File Number. ET -I-0039 CITY OF TUKWILA MITIGATED DETERMINATION OF NONSIGNIFICANCE (MDNS) DESCRIPTION OF PROPOSAL: CONSTRUCTION OF A 15.000 SF OFFICE BUILDING PROPONENT: JOHN'SOr.-BRALIND A.RCHITECT'S LOCATIOrN OF PROPOSAL, INCLUDING STREET ADDRESS, IF ANY: ADDRESS: 15150 51 AV S PARCEL NO: 984440-0036 SEC/TWN/RNG: 51 AV S & S 151 ST LEAD AGENCY: CITY OF TUKWILA FILE NO: E97-0039 • The City has determined that the proposal does not have a, probable significant adverse impact on the environment. An environmental .impact statement (EI'S) is not required under RCW 43.21c.030(2) (c) . This decis,ion.was made after review of a completed environmental checklist and other information on file with the lead agency. This information is avai.l`able to the public on request. The conditions to this..SEPA Determination are attached. This DNS is issued under, 197-1.1-340(2). Comments must be submitted by e-ebcjc.,q 2b, I 'IQ . The lead agency will not act . on this proposal for- 15 days from the date below. Steve Lancaster, Responsible Official City of Tukwila, (206) 431-36'30 6300 Southcenter Boulevard Tukwila, WA 98188 F&),tvc-i-t_ l Li 558 Date Copies of the procedures for.. SEPA appeals are available with the Department of Community Development. • • City of Tukwila John W. Rants, Mayor apartment of Community Development Steve Lancaster, Director MEMORANDUM To: Steve Lancaster From: Michael Jenkins Date: February 10, 1998 Re: E97-0039, 51st Ave S. Office Building, 15150 - 51st Ave S. Project Description: This SEPA review is for the construction of a 15,000 square foot, two-story office building. Agencies with jurisdiction: None Summary of Primary Impacts: • Earth Steepest slopes are up to 50% along the west property line. The bulk of the development area will be located in the center of the site, where slopes are between 6% and 15%. A geotechnical report has been submitted. 72% of the site will include impervious surfaces. Approximately 2,300 cubic yards of cut and fill will be needed. Earthwork will expose soil to erosion. Site grading is anticipated between July and September. A temporary erosion control plan will be submitted by applicant. A land altering permit will be required. • Air Dust will be generated during construction, with watering as necessary to control dust. 6300 Southcenter Boulevard, Suite #100 ° Tukwila, Washington 98188 ° (206) 431-3670 0 Fax (206) 431-3665 E97-0039 - 51st Ave S. Office wilding 15150 -51st Ave S. February 10, 1998 • Water • No surface water on-site. No ground water will be withdrawn. Surface water runoff from impervious surfaces will be collected and treated on-site prior to discharge to off-site system. A level one drainage analysis will be required at the time of application for a Development Permit. An oil/water separator, coalescing plate and detention facility will be the major on-site water treatment facilities. The storm drainage system must comply with the city's storm water management ordinance. • Plants A variety of deciduous trees and grasses are located on-site, including alders with calipers width up to 16 inches. A landscape plan has been submitted with the required Design Review application, to be approved by the Board of Architectural Review. • Animals No threatened or endangered species. • Energy/Natural Resources Electricity and/or natural gas will be used to heat proposed structure. The structure must comply with the Washington State Energy Code. • Environmental Health No known environmental hazards. Noise will be generated both during 4-5 month construction period and from traffic noise after project is completed. Construction activities and use of building during occupancy must comply with Tukwila's Noise Ordinance. • Land/Shoreline Use The property is currently vacant. Properties directly adjacent to the project are all zoned Office '0', with some properties that currently have residential uses. Across from the 51st Ave frontage are properties zoned Low Density Residential. Approximately 40 to 50 people will work in the proposed building. Approval by the Board of Architectural Review is required prior to filing of a Development Permit. Approval of a Lot Consolidation Permit may be required prior to issuance of a building permit. E97-0039 - 51st Ave S. Office 13-uilding 15150 - 51st Ave S. February 10, 1998 • • Housing No housing is proposed nor will any residential structures be removed. • Aesthetics The proposed building will be approximately 35 feet high, using Concrete Masonry Units (CMU), brick, EIFS and a standing seam metal roof as building materials. As referenced, approval of the project by the Board of Architectural Review is required. • Light and Glare Glare will occur as a result of exterior lights. Use of light shields or reduced candle power may be required to avoid negative impact on adjacent residential uses. A lighting plan was submitted, to be approved as part of Design Review application before the Board of Architectural review. • Recreation No impact. • Historic/Cultural Preservation No known places or landmarks. • Transportation The project fronts 51st Ave S. but gains access from S. 151st due to slopes that prevent access from 51st Ave S. The site is located approximately 1/2 mile from a transit stop. Parking for 64 units is included, with a minimum requirement of 45 spaces. A traffic analysis was submitted by the applicant. The analysis shows that the proposed development will generate additional trips along adjacent substandard roads and may generate additional pedestrian traffic, which will increase pedestrian exposure to accident risk. Slopes for the parking area must not exceed 5% and not exceed 15% for driveway, in support of TMC 18.56. S. 151st is a sub -standard roadway lacking curb, gutter, sidewalk, storm drainage, shoulders and street lighting. To ensure safe pedestrian access due to this potentially hazardous deficiency, pedestrian and safety improvements to S. 151st between 51st Ave S. and 52nd Ave S will be required, in support of Comprehensive Plan policies 1.8.5, 8.1.1, 8.1.2 and 13.5.4 and TMC The project must comply with the City's concurrency ordinance, TMC 9.48, to ensure that the Level of Service (LOS) standards are maintained. 11 E97-0039 - 51st Ave S. Office 1uilding 15150 - 51st Ave S. February 10, 1998 • Public Services The facility may require fire and police protection as well as emergency services. • Utilities The applicant included Certificates of Water and Sewer availability. Electric, gas and telephone services will be secured Recommendations: MDNS, with two conditions: 1. The applicant shall construct a paved shoulder from the parcel access point on S. 151st to 51st Ave S. along the north portion of S. 151st, that meets City of Tukwila design standards. 2. The applicant shall install a luminare on the existing power pole across from the S. 151st access point. Address: Applicant: Permit No: Type: Location: Parcel #: Zoning: �� �� �� �� 15150 51 AV S MEL EASTER E97-0039 P-SEPA 51 AV S & 151ST 934440-0036 0 CITY TUKWILA CONDITIONS MSC Status: ISSUED Applied: 12/19/1997 Approved: 02/10/1998 **+**4+***°+�+°^^^*4+****+*44*a444*^+*:iek+*+44/^*++**4+*+^***4*^°++^^+A~^4^++ 1. THE APPLICANT SHALL CONSTRUCT A PAVED SHOULDER. FROM THE PARCEL ACCESS POINT -ON 3. 151ST T0 51ST AVE S, ALONG THE NORTH PORTION OF 3. 151ST THAT MEETS CITY OF TUKWILA DESIGN STANDARDS � 2. THE APPLICANT SHALL IN5TALL,A .LUMINARE ONTHE EXISTING POWER POLE ACROSS FROM THE S.jl5lST ACCESS POINT. � CITY OffrUKWILA • Department of Community Development 6300 Southcenter Boulevard, Tukwila, WA 98188 Telephone: (206) 431-3670 SEPA APPLICATION CHECKLIST FOR STAFF USE ONLY Planner File. Number: Receipt Number Cross-reference files: Applicant notified of incomplete application Applicantnotified of complete application: .............. Notice: of application issued: A. NAME OF PROJECT/DEVELOPMENT: 51st Avenue Office Building 4 B. LOCATION OF PROJECT/DEVELOPMENT: (address and accessors parcel number(s)) Proposed development is located on the east sib of 51st Avenue South approximately 135 feet south of S. 151st St. with access from S: 151st St. Quarter: NW Section: 23 Township: 23N . Range:, 4E a (This information may be found on your tax statement) C. PROJECT DESCRIPTION: Construction of (1) - 15,000 g.s.f. office building and associated parking and site amenities. D. APPLICANT: NAME: Mel Easter - Johnson Braund Design Group, Inc. ADDRESS: 130 Andover Park East, Suite No. 301, Seattle, WA 98188 PHONE: (206) 431-7960 SIGNATURE: o..E /x//9/9 51ST AVENUE OFFICE 'BUILDING TRAFFIC IMPACT ANALYSIS Prepared for Mr. Greg Diener, President Pacific Engineering Design Inc. 130 Andover Park East, Suite 300 Seattle, WA 98188 Transportation Planning & Engineering, Inc. �pE 2101 -112th Avenue N.E., Suite 110 Bellevue, Washington 98004 (206) 455.5320 E17.00 3 1 RECEIVED DEC 2 2 1997 COMMUNITY DEVELOPMENT 51ST AVENUE OFFICE BUILDING TRAFFIC IMPACT ANALYSIS Prepared for Mr. Greg Diener, President Pacific Engineering Design Inc. 130 Andover Park East, Suite 300 Seattle, WA 98188 Prepared by TRANSPORTATION PLANNING & ENGINEERING, INC. 2101 - 112th Ave. N.E., Suite 110 Bellevue, Washington 98004 Telephone - (425) 455-5320 FAX - (425) 453-7180 December 19, 1997 1 EXPIRES 9151 97 1 IVICTOR It I i ; 101' P E: Presictum DAVID N. ENDER, P E Vi.:e P�es�uem TRANSPORTATION PLANNING & ENGINEERING, INC. Mr. Greg Diener, President Pacific Engineering Design Inc. 130 Andover Park East, Suite 300 Seattle, WA 98188 Re: 51st Avenue Office Building Traffic Impact Analysis Dear Mr. Diener: 2101 - 1121h AVENUE N E . SUITE 110 -- BELLEVUE, WASHINGTON 08004 TELEPHONE (425) 455-5320 FACSIMILE (425) 453-7180 December 19, 1997 We are pleased to present this traffic impact analysis for the proposed 51st Avenue Office Building project. The project site is located in the southeast quadrant of the 51st Ave. S./S. 151st St. intersection in the City of Tukwila. We have visited the project site and surrounding street network. The scope of this study is based on the City's Pre -Application Checklist for this project dated 11/13/97, a copy of which is attached. However, the scope has been „t14.o modified based on discussions with City staff to not include pedestrian safety and --eet-aK ? access evaluation nor a sight distance study' The intersection level of service analysis is limited to the 51st Ave. S./S. 151st St. intersection and the 52nd Ave. S./S. 154th St. intersection. PROJECT DESCRIPTION Figure 1 is a vicinity map showing the location of the site and the surrounding street network. Figure 2 shows a preliminary site plan received by TP&E on December 16, 1997. The proposed 15,000 gross square foot (g.s.f) two-story office building would be located near the center of the site. Two parking Tots, one on the west side of the building and one on the east side of the building, would provide about 64 parking stalls. The site has a approximately 187 feet of frontage on 51st Ave. S., and is located about 78 feet south of the S. 151st St. right of way. Access would be via one 20 foot wide driveway intersecting S. 151st St. about 141 feet west of 52nd Ave. S. (measured center to center). The driveway would be centered within a 30 foot wide access easement extending north from the northeast corner of the site. TpE Mr. Greg Diener Pacific Engineering Design Inc. December 19, 1997 Page - 2 - EXISTING CONDITIONS Roadway Facilities 51st Ave. S. is a two lane collector arterial with a 25 MPH posted speed limit. The street has a 60 foot wide right of way, and is marked with a double yellow center stripe formed by raised pavement markers. North of S. 151st St., 51st Ave. S. has a straight horizontal alignment, but a rolling vertical alignment. There are two ten -foot wide traffic lanes, and a painted white edge stripe and a six foot wide paved shoulder on the west side. South of S. 151st St., 51st Ave. S. was recently reconstructed, including replacement of the bridge over S. 154th Street. The new pavement is approximately 36 feet wide, including two 12 foot wide travel lanes, and white edge stripes and six foot wide paved shoulders on both sides. The 51st Ave. S./S. 151st St. intersection is a "T" intersection with all -way stop sign control. Stop ahead warning:. signs are posted on 51st Ave. S. on both approaches to the intersection. S. 151st St. is a two lane local access street with a pavement width of 18 to 20 tr =a`"� feet, within a 30 foot right of way. The street is marked with a double yellow center ''' stripe formed by raised pavement markers, and painted white edge stripes on both sides. The street has no curb, gutter, sidewalk or shoulder improvements. From 51st Ave. S., S. 151st St. slopes steeply downward at a grade of about 20%, reducing to about 4.5% at the 52nd Ave. S. intersection. The street is posted at both ends with "Watch For Ice" warning signs and truck exclusion signs. 52nd Ave. S. is a two lane local access street within a 60 foot wide right of way. The street has curb, gutter and sidewalk for most of its length. The pavement width varies from about 24 feet at the north end to 30 feet at the south end. 52nd Ave. S. is stop sign controlled at its "T" intersection with S. 154th Street. Just north of the intersection, truck exclusion, "Local Access Only," 14% grade warning, and "Very Steep, Impaired Vision Ahead" signs are posted. The 52nd Ave. S./S. 151st St. right angle turn is posted with turn warning signs and a large arrow sign. S. 154th St. is a minor arterial with a 35 MPH posted speed limit. At the 52nd Ave. S. intersection, S. 154th St. has a westbound right turn only lane and a westbound through only lane. The eastbound approach to the intersection is within a taper from one lane west of the intersection to two lanes east of the intersection. At the intersection, the eastbound approach has sufficient width for eastbound through T083597.Rpt Mr. Greg Diener Pacific Engineering Design Inc. December 19, 1997 Page -3- TpE vehicles to pass to the right of a stopped vehicle waiting to turn left into 52nd Ave. South. Traffic Volumes Figure 3 shows existing AM peak hour, noon peak hour, and PM peak hour traffic volumes at the 51st Ave. S./S. 151st St. intersection and at the 52nd Ave. S./S. 154th St. intersection. These volumes were counted by Traffic Count Consultants, Inc. on Tuesday, December 16, 1997. Copies of the traffic count summary sheets are attached. The City has a control count location on Klickitat Drive north of 53rd Ave. S., which is on the continuation of 51st Ave. S. to the south. The City has conducted machine -recorded traffic volume counts, by direction and recorded in 15 minute intervals, at this location every month for several years. Twelve month average daily traffic volumes at this location provided by the City for the years 1989 through 1996 are as follows: 1989 15,500 1990 15,413 1991 15,118 1992 15,215 1993 14,875 1994 15,089 1995 15,531 1996 14,945 The data for 1997 are not useable since the 51st Ave. S. bridge over S. 154th St. was closed for reconstruction for most of the year. The data shows that the traffic volumes at this location have been very stable during this period, and in fact have dropped somewhat from 1995 to 1996. Level of Service Analysis Level of service (LOS) is a qualitative measure describing operational conditions within a traffic flow, and the perception of these conditions by drivers or passengers. These conditions include factors such as speed, delay, travel time, freedom to maneuver, traffic interruptions, comfort, convenience, and safety. Levels of service are given letter designations, from A to F, with LOS A representing the best T083597.Rpt Mr. Greg Diener Pacific Engineering Design Inc. December 19, 1997 Page - 4 - operating conditions (free flow, little delay) and LOS F the worst (congestion, long delays). Generally, LOS A and B are high, LOS C and D are moderate, and LOS E and F are low. Table 1 shows calculated levels of service (LOS) for existing conditions at the pertinent street intersections. The LOS were calculated using the procedures in the Transportation Research Board Highway Capacity Manual - Special Report 209 3rd Edition updated 1994. The LOS shown indicate overall intersection operation. LOS is determined by the calculated average delay per vehicle. The intersection LOS is an average for every vehicle entering the intersection. The LOS and corresponding average delay in seconds are as follows TYPE OF INTERSECTION A B C D E F Signalized 55.0 >5.0 and 515.0 >15.0 and 525.0 >25.0 and 540.0 >40.0 and 560.0 >60.0 Stop Sign Control 55.0 >5 and 510 >10 and 5 20 >20 and 5 30 >30 and 5 45 >45 The 51st Ave. S./S. 151st St. intersection operates at LOS A at all times under normal conditions. All three approaches to the intersection also individually operate at LOS A. The 52nd Ave. S./S. 154th St. intersection as a whole also operates at LOS A at all times under normal conditions. However, the 52nd Ave. S. approach to the intersection is calculated to operate at LOS C during the AM and noon peak hours, and at LOS F during the PM peak hour. Long delays are calculated for the 52nd Ave. S. approach during the PM peak hour, indicating that drivers turning onto S. 154th St. may face a long wait for an adequate gap. The long delays also indicate that there is queuing on the 52nd Ave. S. approach during the PM peak hour. T083597.Rpt +pE Mr. Greg Diener Pacific Engineering Design Inc. December 19, 1997 Page - 5 - TRIP GENERATION AND DISTRIBUTION The proposed 15,000 g.s.f. 51st Avenue Office Building is expected to generate the vehicular trips during an average weekday and during the street traffic peak hours as shown below: Time Period Trip Equation Trips Entering Trips Exiting Total Average Weekday Ln(T)=0.756x 167 167 334 Ln(X)+3.765 (50%) (50%) AM Peak Hour Ln(T)=0.777x 39 5 44 Ln(X)+1.674 (89%) (11%) Noon Peak Hour n/a 22 23 45 (50%) (50%) PM Peak Hour Ln(T)=0.737x 8 38 46 Ln(X)+1.831 (17%) (83%) The trip generation is calculated using the trip generation equations in the Institute of Transportation Engineers (ITE) Trip Generation, Fifth Edition, 1991 for General Office Building (ITE Land Use Code 710). In the equations, T is the number of trips and X is the number of thousands of gross square feet (g.s.f.) of building floor area. A vehicle trip is defined as a single or one direction vehicle movement with either the origin or destination (exiting or entering) inside the study site. These trip generation values account for all site trips made by all vehicles for all purposes, including employee, customer, visitor, and service and delivery vehicle trips. Trip Generation does not include data for the noon peak hour. The values shown above for the noon peak hour are an average of the values for the AM and PM peak hours. T083597.Rpt Mr. Greg Diener Pacific Engineering Design Inc. December 19, 1997 Page - 6 - Figure 4 shows the estimated trip distribution and the calculated area -wide site - generated traffic volumes. Figure 5 shows the site -generated traffic volumes at the subject intersections near the project site. The distribution is based on the characteristics of the road network, existing traffic volume patterns, the location of likely trip origins and destinations (employment, shopping, social and recreational opportunities), expected travel times, and previous traffic studies. FUTURE TRAFFIC CONDITIONS WITH PROJECT Figure 6 shows estimated future AM, noon and PM peak hour trafficvolumes with the proposed project at full occupancy. The site -generated peak hour traffic volumes shown on Figure 5 were added to the existing peak hour traffic volumes shown on Figure 3 to obtain the Figure 6 volumes. Since the City's control counts show that the volumes in the area have been stable, no background growth factor has been added. Table 1 shows calculated LOS for future with project conditions at the pertinent road intersections. The LOS calculation computer printouts for future conditions with the project are attached. The 51st Ave. S./S. 151st St. intersection will continue to operate at LOS A at all times under normal conditions. The site driveway onto S. 151st St. will also operate at LOS A at all times under normal conditions. The 52nd Ave. S./S. 154th St. intersection as a whole will operate at LOS A during the AM and noon peak hours, and at LOS C during the PM peak hour. The 52nd Ave. S. approach to the intersection is calculated to operate at LOS C during the AM and noon peak hours, and at LOS F during the PM peak hour. Due to the project, delays will increase on the 52nd Ave. S. approach. During the PM peak hour, drivers turning onto S. 154th St. may face a very long wait for an adequate gap, and longer queues will occur on the 52nd Ave. S. approach. TRAFFIC IMPACT MITIGATION REQUIREMENTS The City is currently collecting pro -rata share contributions for eleven street improvement projects on their six year transportation improvement program. Fee rates have been developed for each of the eleven projects. The rates are based on the street traffic noon peak hour. Attached is a copy of a fax transmittal from the City T083597.Rpt Mr. Greg Diener Pacific Engineering Design Inc. December 19, 1997 Page - 7 - dated 5/22/97 including a copy of Table 12 - Mitigation Proportionate Fairshare Costs from the Transportation Element of the City's comprehensive plan. The City's Table 12 shows the derivation of the fee rates, including a rate change and two projects which have been added to the list in handwritten form. Table 2 shows the net new noon peak hour project trips, fee rate and pro -rata share contribution at each location for the proposed 51st Avenue Office Building. The developer should offer to pay a pro -rata share contribution for the identified City street improvement projects, calculated as a total of $3,464 as shown on Table 2. Also, the areas adjacent to the site driveway must be kept clear of view - blocking vegetation or structures in order to ensure good sight distances from the site driveway to approaching traffic on S. 151st Street. If you have any questions, please call me. DHE:es Very truly yours, TRANSPORTATION PLANNING & ENGINEERING, INC. 08--a„,j v E7A, David H. Enger, P.E. Vice President T083597.Rpt TpE TABLE 1 PEAK HOUR LEVEL OF SERVICE SUMMARY 51ST AVENUE OFFICE BUILDING INTERSECTION PEAK HOUR EXISTING 1997 FUTURE WITH PROJECT 51st Ave. S./S. 151st St. AM A 1.6 A 1.7 NOON A 2.0 A 2.2 PM A 4.1 A 4.5 52nd Ave. S./S. 154th St. AM A 0.6 (C 16.4) A 0.7 (C 17.4) NOON A 0.6 (C 10.9) A 0.8 (C 11.8) PM A 4.4 (F 101) C 12.2 (F 230) S. 151st St./Site Driveway AM N/A A 0.6 (A 3.5) NOON N/A A 0.9 (A 3.4) PM N/A A 0.8 (A 3.5) o Number shown is the average stopped delay in seconds per vehicle for the intersection as a whole, which determines the LOS for intersections per the 1985 Highway Capacity Manual, 3rd Edition updated 1994. o Level of service and average stopped delay shown in parenthesis () are for the minor street (stop -controlled) approach to the intersection. T083597.Rpt TABLE 2 PRO -RATA SHARE CONTRIBUTIONS FOR CITY STREET IMPROVEMENT PROJECTS 51ST AVENUE OFFICE BUILDING LOCATION NET NEW NOON PEAK HOUR TRIPS COST PER NET NEW NOON PEAK HOUR TRIP PRO -RATA SHARE CONTRIBUTION Southcenter Pkwy./ Strander Blvd. 5 $140 $700 Andover Park E./ Strander Blvd. 2 $135 $270 Andover Park W./ Strander Blvd. 3 $317 $951 W. Valley Hwy./ S. 180th St. 1 $475 $475 Andover Park E./ Baker Blvd. 0 $377 $0 Andover Park W./ Minkler Blvd. (n/s lefts, signal) 1 • $392 $392 Southcenter Pkwy./ S. 168th St. 1 $167 $167 W. Valley Hwy./ Strander Blvd. 1 $283 $283 Interurban Bridge over Green River 0 $1,122 $0 Southcenter Pkwy./ Minkler Blvd. 1 $137 $137 Andover Park W./ Minkler Blvd. 1 $89 $89 TOTAL $3,464 T083597.Rpt TpE SEATTLE TACONA INTERNATIONAL AIRPORT S :147T4 %. FS ; 7 s.°*, : ;.• of .7IPAPX , - 23 ro Isslr \ ST i 'j .sf4:k ) 7. pt - • VI 51111,!114PWAUllioft.. 5 1" E.,03 \11137L4 41lailt -16:1.41—W PKPIY I NORTH S4TELL7E •71-WIML :.,. • J.1113 CW "Reproduced with permission grcnted by THOMAS BROS. MAPS®. This mop is copyrighted by THOMAS BROS. MAPS®. It is unlawful to copy or reproduce all or any part thereof, whether for personal use or resole, without permission. All rights reserveci." VICINITY MAP 51ST AVENUE OFFICE BUILDING TRAFFIC IMPACT ANALYSIS SITE PLAN 51ST AVENUE OFFICE BUILDING TRAFFIC IMPACT ANALYSIS 51st Ave. S. Tuesday 12-16-97 7:15-8:15 AM 12:30-1:30 PM 4:30-5:30 PM "— 20,9,11 A-19,31,88 39,40,99 21,33,27 —► I Project Site J. 1541.1 rt. S. 151st St. «i 52nd Ave. N not to scale Tuesday 12-16-97 7:30-8:30 AM 12:30-1:30 PM 5:00-6:00 PM �._ 50,63,92 --- 222,384,1113 32,9,18- 556, 322, 448 LEGEND XX,YY,ZZ AM, Noon, PM Peak Hour Traffic Volume & Direction EXISTING PEAK HOUR TRAFFIC VOLUMES 51ST AVENUE OFFICE BUILDING TRAFFIC IMPACT ANALYSIS = S 154tht. Project Site (17 ,2.2 co oszt- co N)00 Legend XX% Trip Distribution Percentage (XX) Average Weekday Traffic Volume X,Y,Z AM, NOON, PM Peak Hour Traffic Volumes ( 10% (33) 4,4,5 2% Gfody (7) \Noy 1,1,1 th t 7% (23) 3,3,3 pkwy — N not to scale Stronder 10% (33) 4,4,5 7% (23) 3,3,3 2% o SITE—GENERATED TRAFFIC VOLUME DISTRIBUTION 51ST AVENUE OFFICE BUILDING TRAFFIC IMPACT ANALYSIS T ^ IIGURE� 4 N-1,2,4 A-2,10,15 ' 20,11,4 19,11,4 r0 C rn I� L IN�- rjN Project Site S. 1544h SI. S. 151st St. N tf) NO O N I I` N not to scale N-18,10,4 2,1,0--1 LEGEND XX,YY,ZZ AM, Noon, PM Peak Hour Traffic Volume & Direction SITE—GENERATED PEAK HOUR TRAFFIC VOLUMES 51ST AVENUE OFFICE BUILDING TRAFFIC IMPACT ANALYSIS (0 N Cn CO O N X21,11,15 ---39,40,99 x21,41,103 20,11,4 21,33,27-0-INI ( S: 151st St. 19,11,4 Iuc� Project Site S. 154th St. N not to scale 52nd Ave. S. N '68,73,96 i 222,384,1113 34,10,18 —1 556,322,448—" LEGEND XX,YY,ZZ —► AM, Noon, PM Peak Hour Traffic Volume & Direction FUTURE PEAK HOUR TRAFFIC VOLUMES WITH PROJECT 51ST AVENUE OFFICE BUILDING TRAFFIC IMPACT ANALYSIS IFIGURE� 6 'METING DATE/TIME, ..-11./.43/97 e-.2.39 r.--.• ITE•ADDRESS: -•: • -.1 .A,Y.Lic.".:••`.151-e's1:; ', • • ' _ , • -• - , • .. ' ' ' ▪ : -. : ... - ., . -,.... - " • -; :: . • -; T "''. ' Cheb-klist CITY OF TUKWILA Department of Community Development Building Division -Permit Center 6300 Southcenter Boulevard, Tukwila, WA 98188 Telephone: (206) 431-3670 RE-APPLICATIONwaiN,04.0.mcwystrxwiG.., -TOM ON 'r • "*. •• 110:c . .5 ledV),-A H2O Meter -Temp. 1 TC2 • 'Vele Count Consultants, Inc, 13023 181th Avenue NE, Woudirwillc, WA Phooc; (425)1161-006G FAX. (423) t1(11-0077 98072 intersection: 61et Ave a a Location: Tukwila Vehicle Volume Summary Date of Count: TUB 12/10/97 Cheolted By; Kg 8 1515t 8t Time Interval From North on (BB) 51et 8t From South on (NU) 51et St From E aid on1Wfl 8 151et St -FromVest on (EB) n/a Interval Total Endln! at T L a R T 1 8 R 1' L 8 II I L. 8 li - I ; • 1 1 6 6 4 1 . 1 1 1 i 1 7:30 A 0 2 15 0 0 0 10 3 0 4 0 8 0 0 046 U:UU A 0'3 20 0 0 0 12 7 0 10 0 5 0 0 0 0 5/ 8:30 A 0 1 17 0 0 0 14 6 0 6 0 4 0 0 0 0 48 .,.... -.. ' 1 0 0 0 0 31 gm A 1 3 13 0 ... 0 0 0 0 8 0 2 0 ' 0 4 0 0 37 9:16-A • 0 0 - -...0 0 -0 0 - - 0 ' 0 0 O — .0 • "0 . - . h ' 174 930A 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 949A 0 0 0 0 . •0 0 0 0 0 0"6 6-- `-6`••••1 • ' ' • ... 10:00 A 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 --- Total Survey 2 14 119 0 0 0 101 34 0 33 0 28 0 0 0 0 329 714 A to 0:16 A .Pealt NOW 15 Ohnitna b 0 20 00 0 0 •••••••1 190 TotaI1 6 70 0 0 0 (41 r0a0 0 r6.--'—'71"r""elmul4""mw 1% •1 • • : 0.89 1.05 n/a 0.83 Legend: T- Number of heavy vehtclea (nreater than 4 whools) Lc Left -Turn CI. (*might Re Right -Turn HV = Heavy VehIclee PHF- Pool( hour Favtor (Peak hour volumo / (4`1119hoot 15 mlnutee4) Pre .arad For; TP&E TM07-512 2. From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 823 6021 Dec.17 1997 7:14AM P06 TC�--rz Traffic Count Consultants, Inc. 13623 184th Avenue NE, Woodinville, WA 9R072 Phone: (425) 861-RR66 FAX: (425) R61..8R77 Turning Movement Diagram 8O 1 4 76 Intersection: 51st Ave S (f E 151st St EB Location: Tukwila WB Date of Count: Tue 12/18191 NB Peak Period: 7:15 A 8:15 A SB Checked By: Kg Intersection Prepared For: TP&E Check hi: 190 Out: 190 %HV PI -IF n/a n/a 0.0% 0.65 0.0% 0.80 1.3% 0.83 0.5% 0.83 TMB7 61* 3 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 023 6021 Dec.17 1997 7:13AM POS TC 2 Traffic Count Consultants, Inc. 13623 184th Avenue Nli, Woodinville, WA 98072 Mono: (425) R61 8866 I'AX: (125) 861-9877 Intor000tlon: Stet Ave Location: Tukwila Vehicle Volume Summary Data of Count: Tue 12/16/97 Chookod By: Kg C 8 161st St Time Irtorvu► From Nardi an (BB) 61st St Front Oouth on (NO) 51st 8t From test on tWB) S 161st Sf From Wost on (Eb) nla lntorvai ' Total 6ndlnQ at 7 L 8 )t T L S-- R T L 3 R ' C 8 ' R i 11:45A.-0' et'- 27,,- t1. , _(1 0 .i8 8 D IT' .0 --0..."..p: 6 b ,b ha. 12:60, b S111 00 0 21 3 6 i' 6' 4 0 0 0 0 40 `1 `1'61 - "'0' fr 0 w r 0 b .,..id... ....2 .,0... .. 5 0 3 .43 o.. l .0..,.., '46- . ' ' ' 46,4.,,, 12: 30 P 0 1 2 10 0 0 0 20 2 0 11 0.. 1 0: 0 ..-- a 0 12:458' 0 v 2 18 13 0 ' 0.. 26 g.: 0 1 $ 0 '1: *a D'. 0 1:00 P" 0 1 14" a0 0 20 50 5 0 2 0 0 0 b • 47 1:16 11 „G" �. . �.,. .._...0 U L 0 . 23 � 11 0 ' 11 : 0......3 .'...0:. ;0•`..•...0.... ..0 _,65;, 1,30P 0 1 17 0 0 0, 20 , 7 0 8 0 3 0, 0 0 0 56 "i.:460 "� u u v u V ..- .'. . b • .. ..'*.h. ..... _ 0.......0 ., .41-... .� ... ...b 0 .... 0 44 0 0-, 0 2:00P 1 0 0' 0 0 0 0 0 0 0 0 0' 0— 0 4 0 o' o' 0 0 0 0„., r 6 0 0 ... ,...0... .,:0 0.. ...0... n..:.b 0 2:30P 0 0 0 0 0 0 0 0 0 0 f 0 0 0-0 0' '0 0 V ' / Tidal Survey 0 14_ 140 0 _ 0 0 101.. 46 0 t16 4 0 20 0 1 0 0 0 445 12:so P to ” 1:38 P Wank Hour Summary 'dotal 0 1 4 1 89 1 0 0 1 0 J 68 1 20 o 1 31 i b T b" 0 0 1 0] 0 230 Approach 73 117 � 46 0 230 961-1V II% 0% 0%, nla.... 096 _ PHI= _ 0.01 _ 0,88 0.87 n/a 6I ' hoyend; T- Nund+ur of hvuvy violdulnu hp tante' than 4 vitt lee%) L. Left -Tum S= Straight R- Right -Tum ITV= Heavy Vehioles PI Fe Poak hour Factor (Peak hour volume / (44Hlgheat 15 minutoa)) Prepared For: TP8.E TM07 613 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 823 6021 Dec.17 1997 7:13AM PO4 T1-42 Traffic Count Consultants, Inc. J 3423 184th Avenue NE, Woodinville, WA 98072 Phone: (42S) 861-8866 t'AX: (425) 861-8877 Turning Movement Diagram 1100-J 217 Intersection: Met Avo t3 161st St EB Location: Tukwila WB Date of Count: Tue 12/16/07 NB Peak Period: 12:30 P 1:30 P 3B Checked By: Kg Intersection Prepared For: TP&E Check In: 230 Out: 230 %HV PHr n/a nla 0.0% 0.67 0.096 0.86 0.0% 0.91 0.0% 0.83 TM97-613 5 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 823 6021 Dec.17 1997 7:12AM P03 TC2 Trtdfic Count Consultants, Inc. 13623 184th Avenue Nit, Woodinvilk:, WA 98072 Phono: (425) 861-tatgn PAX! (425) 861-8877 Veh+t:le Volume Surn am r Interneotlon: blot Ave 8 (g & 161e1 St Locution: Tukwila iime - From Nor$1 on (bR) 51btAve S Interval Endlnt at .49E? Date of Count: Tue 12/16/97 Checked By: Kg Fromouch on (NB) From oat on B) From Weil on (Ea) Interval Total 51st Avo S S 151st at n!a L numin • t0 ': 5 0 0 2 • 0 0 0 73 11a 66 1 8 5;00 P 47 20 5:30 P 0 6-oo 50. 0 0 0 41 2 0 12 0 b. 10. 031 0. 8 0 0 2 38 0 0 0 39 6 0 22 ' 0 1 61'776 211. 15 8 o23 O 13 D D 0 0 0 ftro O 108 O 08 ota PProac 1 4 4:30 P 8:30 p Peak Hour 9 im HV 0% 0% n!e nh Legend: 1'+ Number of heavy vehloluu (ureutor than 4 whoa's) L= Loft -*Turn 0. Etrelght Re Right -Turn HV--- I loavy Vohloloe PHF= Peak hour Factor (Peak hour volume ! (4" II host 16 minuteb)) �^ Prepared For: TPae °,6 -Tura TM97-314 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 023 6021 Dec.17 1997 .7:12AM P02 2 Traffic Count Consultants, inc. 13623 184th Avenue NE, Woodinville, WA 98072 Phone (425) 861-8866 FAX: (425) 861-8877 41 Turning Movement Diagram m� 261 3 3 142 Intersection: 51st Ave S 6 E 151st St EB Location: Tukwila WB Date of Count: Tue 1211t31U1 NB Peak•Period: 4!30 P 5:30 P 8B Checked By: Kg Intersection Prepared For: TPBE Check In: 415 Out: 415 %HV PHF n/a n/a 0.0% 0.71 0-0% 0.79 0.0% 0.82 0.0% 0.92 TMS1 %-514 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 823 6021 Dec. 17 1997 7:17AM P13 T C 2 nape Count Consultants, Inc. 13623 184th Avenue NU, Woodinville, WA 98072 Photic: (42S) 861 8966 PAX! (425) R61-Ak77 Vchicl0 Volume Summary Intersection: 52nd Ava 8 % u 154th fit Location: Tukw1la me Interval Errdiir, at ;4 rom o on ✓,tnd Ave 6 From : ou on nla t ` t jPifp�l, Y; • • . i . • �.i�t • 0 i 1 • / 1 1 :• =r: Date of Count: Tues 12116/97 Checked By: Ku rom act on (WM1 ' From West on (Ica) 6 154th 6t 6 15Ath St 8;••A 0 • - 9: Ti •1 • 9:30 A 0 0 0 0 D 0 0 0 .:' A 1b:oo A o 0 0 o 0 - 6 Interval Total l01.:. ...0 • 0 .5 1 15 / 199 39 11 4 .. 143 • .0 0 62 1 0 8 124 • 22 "17777-1111 • 00 '13 12 07 0 0 0 0 0 1 7 68 0. 0 0 0 0 wa� • 0 0 0 0 0 0 Q Total Surve Q 50 0 13 Q 0 0 0 5 Q 457 7:30 A .....tp t:30 A Peak HPur SNmmn 111101111111111111114111111M NMI 11P22,1 roe PHP 87 6 49 030 0 1586 0.68 a X0.74 0.64 Legend: 'T= Number of heavy vehicles (greater than 4 whuuhi) Lr Left -Turn 0. Straight R= Right -Turn HV= Heavy Vehlolnb PHF= Peak hour Factor (Pock hour volume / (4'Higheet 15 minutes)) Praparod For: TPLE 7M97 -1•01I ver. 2 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 023 6021 Dec.17 1997 7:17AM P12 TC2 Tra. is Count Consultants, Inc. 13623 184111 Avcnuc NE, Woodinville, WA 48072 Pbvnc: (425) 861-8866 VAX: (425) 861.1877 Intersection: Location: Date of Count: Peak Period: checked Liy: 520 Ave s O i 154th 13t TIIkw1Iw Tues 12/16/97 7:30A - 8:30A KU Prepared For: TP&E EB Wn NB SB Intersection Check In! 889 Out: 889 %HV PHF 0.74 0.86 n/a 0.86 0.84 n.79/„ n.4, nla O .8% TMa7-Goa From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 823 6021 Dec.17 1997 11:02AM P02 T C2 7raf c C'oulrt Consul[ants, Inc. 13623 184th Avenue Nit, Woodinville. WA 98072 Phone: (425) 861.986E YA.X: (425) Ir(0-12W77 Intersection: 62nd Ave S 6) Loo4an: Tukwila Vehicle Volume 8umma3liy • Date of Count: Tuna 1211007 Checked By: Kg S 1f;4th St Time Interval Enclbt al From North 52nd on Ave S (98) _ From South on (NO) nla Prom Easi on (WO) 8 164th St From Wort on (EO) 6154th 6t Interval Total T L .« A...... T a . L A$ a , ..a,. a... , 6 a.�-. 6 d"....a.. 0 0 ...r,...,h...7"' ar T4' i..,. 2 ;: 4' 5 -'DI- ' A : a . u. . Y{)4 1$0. 1y.. -0 ¥ 12:00 P l0 0 7-8 12:30 F 0 7 0 4 0 0 0 0 1 0 90 15 1 9 65 0 184 12;48 P O g 0 ' 3 0 .0 ' . 0 . . 0 1 , . 0 82 ` - 12 0 1 04 • p 201 1:00 P 0 : 3 ,,. 0 1 b 0 60 . 0 .. 0 . 0 �, 0 . 4 . 1 0 ' 0 7 105 "Igr 11 -13 1 1- 5 I 81 91 , a ,..0... 2113 .....189:.. 1:115 F' 0 , 3 0,:: 1:30 P 0 11 0 3 0 0 0 0 0 0 98 17 0 0 76 0 205 1:5P. sJ: ..0 •' A .e. "p p 0 Q:4 0-0 d ;.,� f 0 •b- - 0 p p 0•„� 2:00P 0 0 0 0 "-- 6 0 - 0, 0 p.. 0 a . , 0 0• 0 .:0 0 0... 0 b.,., 0 0 0 0 0 .0 0 a 0 0•. 0 0 Z16 0 -0 2:30P. 0 0 0 0 a- 0` 0 a ao 0 0 0 6 a 6 Total Survey 0 74 0 28 0 0 0 0 8 0 738 101 8 21 672 0 1534 12:40 r l0 1130 f' Peek Hour S tar eta I r: t , ; 0 I 8 1_r t • 11 Ap%roe h b 3 • 0 n1a 417 14, X31 . 14 -, 911 it* .. n ..4 •:: I Legend: T= Number or heavy vehloles (greater than 4 wheels) L= Loft -Tum • 8= Straight R= Right -Turn HV- Hoavy Vohloloo PIT= Peak hour Factor (Peak hour volume 1(44I-1I0heal 15 minus )) Propared for: TP@.E - •1 rMer cru 10 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 823 6021 Dec.17 1997 11:01AM P01 irk, Traffic Count Consultants, Inc.. 722 1l [l S 154th St 381 I36n 1H4ih Avenue NL, Woodinvillc, WA 98072 Pliono: (425) 861-8866 FAX: (425) 861-8877 Turnip Movement pia rem 106 43 80 Intersection: Location: Date of Cuunt; Peak Period: Checked By: Prepared For: 52nd Ave S c S 154th st Tukwila 'rues 121109/ 12:30 P Kg TP&E 1:30 P 02 S 154111 St EE3 WB NB SB Intersection 1 350 1 Chuck In: 811 Out; 811 %HV PNF 0.08 0.0% 1.4% n/a 0 �4 n/e 0.0% 0.77 1.0% 0.84 TM97-B 1 O 11 From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 823 6021 Dec.17 1997 7:16AM P10 T Let T1'afiha Count Com ul1ar tlsg Inn. 13623 111401 Avcmrc NI!, Woodinville, WA 98072 P),nne: (425) UM-RR6(. I:AX: (425) 861-8877 Intoraootlon: 62nd Avo 6 :i 164th Location: Tukwila Vehicle Volume Summa Dote of Count: Tues 12/10/07 Checked Hy: KO St Titus Inlni vrl Frrum North on (813) 52nd Ave 8 FromlIouth on (NO) - n/a from East on (WO) 0 154th CI rrom West on (CD) C 1541h 6t Interval Total Ending of T L 0 A 7 L 6 R T L ;. d:1'S 0' 21...., .. 0, .... 7 . : 0 - t) ' 00 . 5 0- l ;f . i0 ..2 ..4.........,90... ...p_. .... 300. . 4:30"P 0 -.is - 0 5 ' 0 d 8 - $ .0 0 224 25 0 122 12 0 8 0 q •:. ..: :.:. d •..••,,2 ' :•:. '" "'1st " ' 2i.: .:.1'.... 1. , . 87 0 ...923 5: r r• 0 12 0 4 0 0 e 1 0 264 19 0 0 97 0 386 ;,1 , -. . 0w 12 r r i 0 0 1:Y 0. 2:• II r _ y. r: 3:30 P 0 9 0 3 d �, 0 0 0 1 0 295 25 0 3 117 0 432 ;,• ; 0 1, ..., .0 5 0 ... � .; ' 4 .0. 1 \!: 0 242 R i .. om.. 1 '' iT . 392'' ii:06 P 0 12 0 6 0 0 0 0 i. 0 282 13 0 3 124 0 450 .8:15 F• 0 d_•P .°:,� °:`...0. ..,0 _ .._ 6:30P 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 ,; : i i t.;.: 0. 0-. 0 i e 0. 0 0 0 q. ....p...... ,0 0. t. 7:00P 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • Total1•••••••••=• Suivai 0 108 , 0 42 0 0 . 0 0 12 0 2032 173 3 22 844 0 3221 Ella P to e3:00 P Peak Hour Summar o'' t 111E1111114111MAIIIIIMMIIIIIIIIMEMINLIMIL111111112112AMEllika 4 8 r ••mu r 1 V 4-4 - ,,•■o •'1• n e•T, v.,.. 1•. PHF - 0.80- Ela 0.94 , 0.91 • L.oeond: T.- Nu,nbor of hoavy vehlclea (Greater then 4 whoolo) L= Left -Turn 8- Btral©ht fl- .RIGht-Turn HV= Hoavy Vehicles PHF= Pak hour Faotor (Pock hour vvlurno / (4•HIghoot 15 minutes)) Prepared For: TP&E TM97-511 iz From : TRAFFIC COUNT CONSULTANTS, INC PHONE No. : 206 023 6021 Dec.17 1997 7:15AM P09 TC2 Trac Count Consultants, Inc. 13623 184111 Avenue NE, Woodinville, WA 98072 ?hum: (425) & 1-RR6( FAX: (423) 861.-KK77 8 Milt Si Turnin�MovOmentDia .ram Intersection: Location; Date of Count: Peak Period: Checked By: 52nd Ave Tukwila Tues 12/16/97 5:00 P Kg • Prepared For; TP&I 154th $t 6:00 P EB WB NB SB Intersection Check In: 1743 Out: 1743 %HV PHF 0.0% 0.91 0.3% n/a 0.0% 0.94 ilia 0.80 0.2% 0.96 13 CITY OF TUKWILA - PUBLIC WORKS DEPT. FAX TRANSMITTAL FAX NUMBER: (206) 431-3665 TO: TITLE: 97 COMPANY: DEPARTMENT: DIVISION: FAX NO. CALLED: I/ 3- 7/50 TOTAL NUMBER OF PAGES TRANSMI'1'n a), INCLUDING 2 THIS COVER SHEET. SENT BY (INITIALS): c...... •••••••o::•s:•arov•<•ae:•N•e:e, :x:,»:n:,n:rv.os..w.:s:•.•.•...:::..........•.•..; ••:..... a ...... OMMENTS/, SSAGE: x.••• ::n'J.w:: • ,lwi'PFve:(..ona•.a�..a .:y:1•r;'::. .:wC::.:1:v•,••:,.v.?.Y.ay.ay.a....,.•�...r....:w..., TUKWILA PUBLIC WORKS DEPT. - 6300 Southcenter Blvd, Tukwila WA 98188 - (206) 433-0179 Southcenter PkWy/168 signal W Valley/Strander NB dual left tum lanes Interurban Bridge widen for dual lefts his i a ' p ' nin level" estimate. Future (Bey(&years C40): ) Minkler (APW - Southcenter PkWy) construct Slane street S 178 St (Southcenter PkWy-WCL) realign (cap/safery/transit) Andover PkWy (T PkWy-180) widen to 5 lanes Andover Pk E (T PkWy-180) widen to 5 lanes @ ints. Southcenter PkWy (180-200) construct 3 and 5 lane street 41-ou imn.Lt9c- November 1993 • e Costs 1990 , 2010 Pk Vol Improvement Cost/ Pk Vol Pk Vol tiff Cost Trip 3,899 4,853 954 $134,000 $140 3,211 3,905 694 .$94,000 3,082 4,016 934 $296,000 5,236 7,760 2,524 $1,200,000 790 1,453 663 $250,000* 2,441 • 3,078 637 $250,000* go 2,425 3,324 899 cp,Qfl 3,433 4,316 883 $250,000* 2,831 3,945 1,114 • $1,250,000* 5-73 0 1,015 1,015 789 1,424 635 1.112 1,833 721 970 1,420 450 408 1,600 1,192 /1960 1? -14 2 -6 -71 -,?1,0 121,1 -c) $135 $317 $475 $377 $392 $283 $1,122 71 s HCS: Unsignalized Intersections Release 2.1d T0835F1A.HCO Page 1 Center For Microcomputers In Transportation University of Florida 512 Weil Hall Gainesville, FL 32611-2083 Ph: (904) 392-0378 Streets: (N -S) 51ST. AVE. S. (E -W) S. 151ST ST. Analyst DHE Date of Analysis 12/18/97 Other Information FUTURE AM PEAK HOUR WITH PROJECT All -way Stop -controlled Intersection No. Lanes Volumes PHF Northbound L T R 0 1 < 0 60 30 .89 .89 Southbound L T R 0 > 1 0 10 70 .83 .83 Eastbound L T R 0 0 0 Westbound L T R 0 > 1 < 0 21 0 21 .65 .65 .65 Volume Summary and Capacity Analysis WorkSheet NB SB EB WB LT Flow Rate 0 12 32 RT Flow Rate 34 0 32 Approach Flow Rate 101 96 64 Proportion LT 0.00 0.13 0.50 Proportion RT - 0.34 0.00 0.50 Opposing Approach Flow Rate 96 101 0 Conflicting Approaches Flow Rate 64 64 197 Proportion, Subject Approach Flow Rate 0.39 0.37 0.25 Proportion, Opposing Approach Flow Rate 0.37 0.39 0.00 Lanes on Subject Approach 1 1 1 Lanes on Opposing Approach 1 1 0 LT, Opposing Approach 12 0 0 RT, Opposing Approach 0 34 0 LT, Conflicting Approaches 32 32 12 RT, Conflicting Approaches 32 32 34 Proportion LT, Opposing Approach 0.13 0.00 0.00 Proportion RT, Opposing Approach 0.00 0.34 0.00 Proportion LT, Conflicting Approaches 0.50 0.50 0.06 Proportion RT, Conflicting Approaches 0.50 0.50 0.17 Approach Capacity 707 806 479 Intersection Performance Summary Approach Approach V/C Average Movement Flow Rate Capacity Ratio Total Delay LOS NB 101 707 0.14 1.7 A SB 96 806 0.12 1.6 A WB 64 479 0.13 1.7 A Intersection Delay = 1.7 Level of Service (Intersection) = A 16 HCS: Unsignalized Intersections Release 2.1d T0835F1N.HCO Page 1 Center For Microcomputers In Transportation University of Florida 512 Weil Hall Gainesville, FL 32611-2083 Ph: (904) 392-0378 Streets: (N -S) 51ST. AVE. S. Analyst DHE Date of Analysis 12/18/97 Other Information FUTURE NOON PEAK HOUR WITH PROJECT All -way Stop -controlled Intersection (E -W) S. 151ST ST. No. Lanes Volumes PHF Northbound L T R O 1 < 0 88 38 .86 .86 Southbound L T R O > 1 0 6 69 .91 .91 Eastbound 0 0 0 Westbound L T R O > 1 < 0 41 0 11 .67 .67 .67 Volume Summary and Capacity Analysis WorkSheet, NB SB EB WB LT Flow Rate 0 7 61 RT Flow Rate 44 0 16 Approach Flow Rate 146 83 77 Proportion LT 0.00 0.08 0.79 Proportion RT 0.30 0.00 0.21 Opposing Approach Flow Rate 83 146 0 Conflicting Approaches Flow Rate 77 77 229 Proportion, Subject Approach Flow Rate 0.48 0.27 0.25 Proportion, Opposing Approach Flow Rate 0.27 0.48 0.00 Lanes on Subject Approach 1 1 1 Lanes on Opposing Approach 1 1 0 LT, Opposing Approach 7 0 0 RT, Opposing Approach 0 44 0 LT, Conflicting Approaches 61 61 7 RT, Conflicting Approaches 16 16 44 Proportion LT, Opposing Approach 0.08 0.00 0.00 Proportion RT, Opposing Approach 0.00 0.30 0.00 Proportion LT, Conflicting Approaches 0.79 0.79 0.03 Proportion RT, Conflicting Approaches 0.21 0.21 0.19 Approach Capacity 566 590 500 Intersection Performance Summary Approach Approach V/C Average Movement Flow Rate Capacity Ratio Total Delay LOS NB 146 566 0.26 2.7 A SB 83 590 0.14 1.7 A WB 77 500 0.15 1.8 A Intersection Delay = 2.2 Level of Service (Intersection) = A 17 HCS: Unsignalized Intersections Release 2.1d T0835F1P.HCO Page 1 Center For Microcomputers In Transportation University of Florida 512 Weil Hall Gainesville, FL 32611-2083 Ph: (904) 392-0378 Streets: (N -S) 51ST. AVE. S. (E -W) S. 151ST ST. Analyst DHE Date of Analysis 12/18/97 Other Information FUTURE PM PEAK HOUR WITH PROJECT All -way Stop -controlled Intersection No. Lanes Volumes PHF Northbound L T R O 1 < 0 126 19 .79 .79 Southbound L T R O > 1 0 12 163 .82 .82 Eastbound L T R 0 0 0 Westbound L T R 0 > 1 < 0 103 0 15 .71 .71 .71 Volume Summary and Capacity Analysis WorkSheet NB SB EB WB LT Flow Rate 0 15 145 RT Flow Rate 24 0 21 Approach Flow Rate 183 214 166 Proportion LT 0.00 0.07 0.87 Proportion RT 0.13 0.00 0.13 Opposing Approach Flow Rate 214 183 0 Conflicting Approaches Flow Rate 166 166 397 Proportion, Subject Approach Flow Rate 0.33 0.38 0.29 Proportion, Opposing Approach Flow Rate 0.38 0.33 0.00 Lanes on Subject Approach 1 1 1 Lanes on Opposing Approach, 1 1 0 LT, Opposing Approach 15 0 0 RT, Opposing Approach 0 24 0 LT, Conflicting Approaches 145 145 15 RT, Conflicting Approaches 21 21 24 Proportion LT, Opposing Approach 0.07 0.00 0.00 Proportion RT, Opposing Approach 0.00 0.13 0.00 Proportion LT, Conflicting Approaches 0.87 0.87 0.04 Proportion RT, Conflicting Approaches 0.13 0.13 0.06 Approach Capacity 446 510 502 Intersection Performance Summary Approach Approach V/C Average Movement Flow Rate Capacity Ratio Total Delay LOS NB 183 446 0.41 4.8 A SB 214 510 0.42 4.9 A WB 166 502 0.33 3.5 A Intersection Delay = 4.5 Level of Service (Intersection) = A /8 HCS: Unsignalized Intersections Release 2.1d T0835F2A.HCO Page 1 Center For Microcomputers In Transportation University of Florida 512 Weil Hall Gainesville, FL 32611-2083 Ph: (904) 392-0378 Streets: (N -S) 52ND AVE. S. Major Street DirectionEW Length of Time Analyzed60 (min) Analyst DHE Date of Analysis 12/18/97 Other Information FUTURE AM PEAK HOUR WITH PROJECT Two-way Stop -controlled Intersection (E -W) S. 154TH ST. No. Lanes Stop/Yield Volumes PHF Grade MC's (%) SU/RV's (%) CV's (%) PCE's 1 Eastbound 1 L T R 0 > 1 0 N 34 556 .74 .74 -2 0 0 1 0.91 Westbound L T R 0 1 1 N 222 68 .85 .85 2 Northbound L T R 0 0 0 Southbound L' T R 0 > 1 < 0 27 0 4 .66 .66 .66 0 0 0 0 0 0 0 0 0 0 1.00 1.00 1.00 Vehicle Maneuver Adjustment Factors Critical Gap (tg) Follow-up Time (tf) Left Turn Major Road Right Turn Minor Road Through Traffic Minor Road Left Turn Minor Road 5.00 5.50 6.00 6.50 2.10 2.60 3.30 3.40 1? HCS: Unsignalized Intersections Release 2.1d T0835F2A.HCO Page 2 Worksheet for TWSC Intersection Step 1: RT from Minor Street NB SB Conflicting Flows: (vph) Potential Capacity: (pcph) Movement Capacity: (pcph) Prob. of Queue -Free State: 261 1021 1021 0.99 Step 2: LT from Major Street WB EB Conflicting Flows: (vph) 341 Potential Capacity: (pcph) 11.79 Movement Capacity: (pcph) 1179 Prob. of Queue -Free State: 0.96 TH Saturation Flow Rate: (pcphpl) 1700 Major LT Shared Lane Prob. of Queue -Free State: 0.94 Step 3: TH from Minor Street NB SB Conflicting Flows: (vph) 1058 Potential Capacity: (pcph) 304 Capacity Adjustment Factor due to Impeding Movements 0.94 Movement Capacity: (pcph) 285 Prob. of Queue -Free State: 1.00 Step 4: LT from Minor Street NB SB Conflicting Flows: (vph) Potential Capacity: (pcph) Major LT, Minor TH Impedance Factor: Adjusted Impedance Factor: Capacity Adjustment Factor due to Impeding Movements Movement Capacity: (pcph) 1098 245 0.94 0.94 0.94 229 HCS: Unsignalized Intersections Release 2.1d T0835F2A.HCO Page 3 Intersection Performance Summary Avg. 95% Flow Move Shared Total Queue Approach Rate Cap Cap Delay Length LOS Delay Movement (pcph) (pcph) (pcph)(sec/veh) (veh) (sec/veh) SB L 41 229 > SB T 0 285 > 254 17.4 0.7 C 17.4 SB R 6 1021 > EB L 42 1179 3.2 0.0 A 0.2 Intersection Delay = 0.7 sec/veh HCS: Unsignalized Intersections Release 2.1d T0835F2N.HCO Page 1 Center For Microcomputers In Transportation University of Florida 512 Weil Hall Gainesville, FL 32611-2083 Ph: (904) 392-0378 Streets: (N -S) 52ND AVE. S. (E -W) S. 154TH ST. Major Street DirectionEW Length of Time Analyzed60 (min) Analyst DHE Date of Analysis 12/18/97 Other Information FUTURE NOON PEAK HOUR WITH PROJECT Two-way Stop -controlled Intersection No. Lanes Stop/Yield Volumes PHF Grade MC's (%) SU/RV's (%) CV's (%) PCE's 1 Eastbound 1 L T R 0 > 1 0 N 10 322 .86 .86 -2 0 0 1 0.91 Westbound L T R 0 1 1 N 384 73 .94 .94 2 Northbound L T R 0 0 0 Southbound L T R 0 > 1 < 0 46 0 8 .77 .77 .77 0 0 0 0 0 0 0 0 0 0 1.00 1.00 1.00 Vehicle Maneuver Adjustment Factors Critical Gap (tg) Follow-up Time (tf) Left Turn Major Road Right Turn Minor Road Through Traffic Minor Road Left Turn Minor Road 5.00 5.50 6.00 6.50 2.10 2.60 3.30 3.40 zz HCS: Unsignalized Intersections Release 2.ld T0835F2N.HCO Page 2 Worksheet for TWSC Intersection Step 1: RT from Minor Street NB SB Conflicting Flows: (vph) 409 Potential Capacity: (pcph) 859 Movement Capacity: (pcph) 859 Prob. of Queue -Free State: 0.99 Step 2: LT from Major Street WB EB Conflicting Flows: (vph) 487 Potential Capacity: (pcph) 1005 Movement Capacity: (pcph) 1005 Prob. of Queue -Free State: 0.99 TH Saturation Flow Rate: (pcphpl) 1700 Major LT Shared Lane Prob. of Queue -Free State: 0.99 Step 3: TH from Minor Street NB SB Conflicting Flows: (vph) Potential Capacity: (pcph) Capacity Adjustment Factor due to Impeding Movements Movement Capacity: (pcph) Prob. of Queue -Free State: 795 417 0.99 411 1.00 Step 4: LT from Minor Street NB SB Conflicting Flows: (vph) Potential Capacity: (pcph) Major LT, Minor TH Impedance Factor: Adjusted Impedance Factor: Capacity Adjustment Factor due to Impeding Movements Movement Capacity: (pcph) 834 348 0.99 0.99 0.99 343 23 HCS: Unsignalized Intersections Release 2.1d T0835F2N.HCO Page 3 Intersection Performance Summary Avg. 95% Flow Move Shared Total Queue Approach Rate Cap Cap Delay Length LOS Delay Movement (pcph) (pcph) (pcph)(sec/veh) (veh) (sec/veh) SB L 60 343 > SB T 0 411 > 375 11.8 0.8 C 11.8 SB R 10 859 > EB ,L 11 1005 3.6 0.0 A 0.1 Intersection Delay = 0.8 see/veh' HCS: Unsignalized Intersections Release 2.1d T0835F2P.HCO Page 1 Center For Microcomputers In Transportation University of Florida 512 Weil Hall Gainesville, FL 32611-2083 Ph: (904) 392-0378 Streets: (N -S) 52ND AVE. S. (E -W) S. 154TH ST. Major Street DirectionEW Length of Time Analyzed▪ 60 (min) Analyst DHE Date of Analysis 12/18/97 Other Information FUTURE PM PEAK HOUR WITH PROJECT Two-way Stop -controlled Intersection No. Lanes Stop/Yield Volumes PHF ' Grade MC's (%) SU/RV's (%) CV's (%) PCE's Eastbound L T R 0 > 1 0 N 18 448 .91 .91 -2 0 0 0 0.90 Westbound L T R 0 1 1 N 1113 96 .94 .94 2 Northbound L T R 0 0 0 Southbound L T R O > 1 < 0 68 0 25 .8 .8 .8 0 0 0 0 0 0 0 0 0 0 1.00 1.00 1.00 Vehicle Maneuver Adjustment Factors Critical Gap (tg) Follow-up Time (tf) Left Turn Major Road Right Turn Minor Road Through Traffic Minor Road Left Turn Minor Road 5.00 5.50 6.00 6.50 2.10 2.60 3.30 3.40 HCS: Unsignalized Intersections Release 2.1d T0835F2P.HCO Page 2 Worksheet for TWSC Intersection Step 1: RT from Minor Street NB SB Conflicting Flows: (vph) 1184 Potential Capacity: (pcph) 348 Movement Capacity: (pcph) 348 Prob. of Queue -Free State: 0.91 Step 2: LT from Major Street WB EB Conflicting Flows: (vph) 1286 Potential Capacity: (pcph) 418 Movement Capacity: (pcph) 418 Prob. of Queue -Free State: 0.96 TH Saturation Flow Rate: (pcphpl) 1700 Major LT Shared Lane Prob. of Queue -Free State: 0.94 Step 3: TH from Minor Street NB SB Conflicting Flows: (vph) r 1696 Potential Capacity: (pcph) 141 Capacity Adjustment Factor due to Impeding Movements 0.94 Movement Capacity: (pcph) 132 Prob. of Queue -Free State: 1.00 Step 4: LT from Minor Street NB SB Conflicting Flows: (vph) Potential Capacity: (pcph) Major LT, Minor TH Impedance Factor: Adjusted Impedance Factor: Capacity Adjustment Factor due to Impeding Movements Movement Capacity: (pcph) 1747 103 0.94 0.94 0.94 97 26 HCS: Unsignalized Intersections Release 2.1d T0835F2P.HCO Page 3 Intersection Performance Summary Avg. 95% Flow Move Shared Total Queue Approach Rate Cap Cap Delay Length LOS Delay Movement (pcph) (pcph) (pcph)(sec/veh) (veh) (sec/veh) SB L 85 97 > SB T 0 132 > 120 230.4 11.1 F 230.4 SB R 31 348 > EB L 18 418 9.0 0.0 B 0.3 Intersection Delay = 12.2 sec/veh 27 • • GEOTECH CONSULTANTS, INC. 13256 NE 20th Street, Suite 16 Bellevue. WA 98005 (425) 747-5618 FAX (425) 747-8561 Johnson Braund Design Group, Inc. 130 Andover Park East, Suite 301 Seattle, Washington 98188 Attention: Mel Easter Subject: Geotechnical Engineering Study Proposed Johnson Braund/Pacific Engineering Office Buildings 51st Avenue South near South 151st Street Tukwila, Washington Dear Mr. Easter: December 2, 1997 JN 97412 REC LVED DEC 221997 CMMUNITY DEVELOPMENT €97 • of, We are pleased to present this geotechnical engineering study for the proposed office buildings to be constructed on 51st Avenue South near South 151st Street in Tukwila, Washington. The scope of our work consisted of. exploring site subsurface conditions, and then developing this report to provide recommendations for general earthwork and design criteria for foundations, retaining walls, and pavements. This work was authorized by your acceptance of our confirming proposal, dated November 6, 1997. The subsurface conditions of the proposed development site were explored with five test pits that encountered silty sands with some gravel overlying relatively hard gray silts and clays. It is our opinion that the proposed buildings may be constructed on conventional foundations placed on native soils. The soils are highly moisture -sensitive and thus, earthwork would be most economical to perform during the normally dry summer months. Groundwater was found in one test pit. The on-site soils are not suitable for structural fill if they are above optimum moisture content. The attached report contains a discussion of the study and our recommendations. Please contact us if there are any questions regarding this report or if we can be of further assistance during the design and construction phases of this project. :mmm Respectfully submitted, GEOTECH CONSULTANTS, INC. /1 /41, James R. Finley, P.E. Principal GEOTECHNICAL ENGINEERING STUDY Proposed Johnson Braund/Pacific Engineering Office Buildings 51st Avenue South near South 151st Street Tukwila, Washington This report presents the findings and recommendations of our geotechnical engineering study for the site of two proposed office buildings to be constructed near the northeast comer of 51st Avenue South and South 151st Street in Tukwila, Washington. The Vicinity Map, Plate 1, illustrates the general location of the site. We were provided with a site plan which shows the proposed buildings, site topography, and site boundaries. We anticipate that two L-shaped office buildings will be constructed on the site. Since the site slopes down to the east, we anticipate that relatively Targe retaining walls will be constructed on the west side of the property. SITE CONDITIONS Surface The site is bordered on the west by 51st Avenue South, by commercial development on the east and south, and an older single-family residence on the north. Access to the site is through a 30 foot easement off of South 151st Street. The site is presently covered with brush and small trees. It slopes downwards from an elevation of approximately 144 feet at the northwest corner to a low of approximately 100 feet in the southeast corner. The slope is relatively steep near 51st Avenue South but moderates on the lower two-thirds of the property. Subsurface The subsurface conditions were explored by excavating five test pits at the approximate locations shown on the Site Exploration Plan, Plate 2. The field exploration program was based upon the proposed construction and required design criteria, the site topography and access, the subsurface conditions revealed during excavation, the scope of work outlined in our proposal, and on time and budget constraints. The test pits were excavated on November 12, 1997 with a rubber -tired backhoe. A geotechnical engineer from our staff observed the excavation process, logged the test pits, and obtained representative samples of the soil encountered. "Grab" samples of selected subsurface soil were collected from the backhoe bucket. The Test Pit Logs are attached to this report as Plates 3 through 5. All of the test pits encountered a brown, silty, gravelly sand near the ground surface. These soils are medium -dense to dense and contain cobbles and boulders. We observed a Targe granite boulder approximately 8 foot in diameter on the western one-half of the site in the vicinity of the furthermost proposed office building. Dense, silty sands overlie a blue -gray, clayey silt. All the test pits were terminated in this hard, clayey silt, with the exception of Test Pit 3. GEOTECH CONSULTANTS, INC. Johnson Braund Design Group, nc. December 2, 1997 • JN 97412 Page 2 The final logs represent our interpretations of the field logs and laboratory tests. The stratification lines on the logs represent the approximate boundaries between soil types at the exploration locations. The actual transition between soil types may be gradual, and subsurface conditions can vary between exploration locations. The logs provide specific subsurface information only at the locations tested. The relative densities and moisture descriptions indicated on the test pit logs are interpretive descriptions based on the conditions observed during excavation. The compaction of backfill was not in the scope of our services. Loose soil will therefore be found in the area of the test pits. If this presents a problem, the backfill will need to be removed and replaced with structural fill during construction. Groundwater We observed moderate groundwater seepage at a depth of 5.5 feet in Test Pit 1. The remainder of the test pits did not encounter groundwater.. However, the test pits were left open for only a short period of time, and groundwater levels were not monitored. We anticipate that the excavation could encounter groundwater perched on top of the relatively impervious blue -gray, clayey silts within more permeable lenses of the silty sands. CONCLUSIONS AND RECOMMENDATIONS General It is our opinion that the proposed buildings may be constructed on conventional foundations founded on native soils. A Targe retaining wall may be required on the west side of the property. This wall may be constructed of a variety of materials. We recommend, however, that rockeries :be limited to a height of 6 feet. Groundwater seepage may be encountered in the excavation as moderate groundwater was encountered in Test Pit 1, located at approximately elevation of 135J feet, in the northwest corner of the site) It appears that some of the site soils may be suitable for use as structural fill% However, soils below the ground water level, and the silts and clays are not suitable for use as structural fill and should be removed from the site. The silty sands are also highly moisture -sensitive and must be j placed at or near optimum moisture content. Typically, it is necessary to reduce the soil moisture prior to placement of fill. Reduction of soil moisture is only possible when the site grading takes place during the normally dry summer and fall months (July - September). It would be more economical to perform site grading during this time period when the soils are generally more dry. If work takes place when the soils are wet, or during rainy periods, it will be necessary to import more granular, structural fill. Conventional Foundations The proposed structure can be supported on conventional continuous and spread footings bearing on undisturbed, native, medium -dense to dense soil or on structural fill placed above competent native soils. See the later sub -section entitled General Earthwork and Structural Fill for recommendations regarding the placement and compaction of structural fill beneath structures. GEOTECH CONSULTANTS, INC. Johnson Braund Design Grou , nc. December 2, 1997 • JN 97412 Page 3 We recommend that continuous and individual spread footings have minimum widths of 12 and 16 inches, respectively. They should be bottomed at least 18 inches below the lowest adjacent finish ground surface for frost protection. The local building codes should be reviewed to determine if different footing widths or embedment depths are required. Footing subgrades must be cleaned of loose or disturbed soil prior to pouring concrete. Depending upon site and equipment constraints, this may require removing the disturbed soil by hand. The following allowable bearing pressure is appropriate for footings constructed according to the above recommendations: BEARING CONDITION ALLOWABLE BEARING PRESSURE Placed directly on competent, native soil, depth < 4'.B.G. 2,000 psf Placed directly on competent, 5,000 psf native soil, depth > 4' B.G. Supported on structural fill placed above competent, native soil 2,000 psf Where: (i) psf is pounds per square foot, (ii)B.G. = below existing grade For the above design criteria, it is anticipated that the total post -construction settlement of footings founded on competent, native soil, or on structural fill up to 5 feet in thickness, will be about one- half inch. Lateral loads due to wind or seismic forces may be resisted by friction between the foundation and the bearing soil, or by passive earth pressure acting on the vertical, embedded portions of the foundation. For the latter condition, the foundation must be either poured directly against relatively level, undisturbed soil or surrounded by level, structural fill. We recommend using the following design values for the foundation's resistance to lateral loading: PARAMETER DESIGN VALUE Coefficient of Friction Passive Earth Pressure • 0.40 350 pcf Where: (i) pcf is pounds per cubic foot, and (ii) passive earth pressure Is computed using the equivalent fluid density. If the ground in front of a foundation is loose or sloping, the passive earth pressure given above will not be appropriate. We recommend a safety factor of at least 1.5 for the foundation's resistance to lateral loading, when using the above design values. GEOTECH CONSULTANTS, INC. Johnson Braund Design Groupnc. December 2, 1997 Seismic Considerations JN 97412 Page 4 The site is located within Seismic Zone 3, as illustrated on Figure No. 16-2 of the 1994 Uniform Building Code (UBC). In accordance with Table 16-J of the 1994 UBC, the site soil profile is best represented by Profile Type S1. The site soils are not subject to seismic liquefaction. Slabs -on -Grade The building floors may be constructed as slabs -on -grade atop native or fill soils. The subgrade soil must be in a firm, non -yielding condition at the time of slab construction or underslab fill placement. Any soft areas encountered should be excavated and replaced with select, imported, structural fill. All slabs -on -grade should be underlain by a capillary break or drainage layer consisting of a minimum 4 -inch thickness of coarse, free -draining, structural fill with a gradation similar to that discussed later in Permanent Foundation and Retaining Walis. In areas where the passage of moisture through the slab is undesirable, a vapor barrier, such as a 6 -mil plastic membrane, should be placed beneath the slab. Additionally, sand should be used in the fine -grading process to reduce damage to the vapor barrier, to provide uniform support under the slab, and to reduce shrinkage cracking by improving the concrete curing process. Isolation joints should be provided where the slabs intersect columns and walls. Control and expansion joints should also be used to control cracking from expansion and contraction. Saw cuts or preformed strip joints used to control shrinkage cracking should extend through the upper one-fourth of the slab. The spacing of control or expansion joints depends on the slab shape and the amount of steel placed in it. Reducing the water -to -cement ratio of the concrete and curing the concrete, by preventing the evaporation of free water until cement hydration occurs, will also reduce shrinkage cracking. Permanent Foundation and Retaining Walis Retaining walls backfilled on only one side should be designed to resist the lateral earth pressures imposed by the soil they retain. The following recommended design parameters are for walls that restrain level backfill: PARAMETER DESIGN VALUE Active Earth Pressure * 35 pcf Passive Earth Pressure Coefficient of Friction Soil Unit Weight 400 pcf 0.45 130 pcf Where: (i) pcf is pounds per cubic foot, and (ii) active and passive earth pressures are computed using the equivalent fluid pressures. GEOTECH CONSULTANTS, INC. Johnson Braund Design Group, Inc. December 2, 1997 • • For a restrained wall that cannot deflect at least 0.002 times its height, a uniform lateral pressure equal to 10 psf times the height of the wall should be added to the above active equivalent fluid pressure. JN 97412 Page 5 We recommend a safety factor of at least 1.5 for overturning and sliding, when using the above values to design the walls. The design values given above do not include the effects of any hydrostatic pressures behind the walls and assume that no surcharge slopes or Toads, such as vehicles, will be placed behind the walls. If these conditions exist, those pressures should be added to the above lateral soil pressures. Also, if sloping backfill is desired behind the walls, we will need to be given the wall dimensions and the slope of the backfill in order to provide the appropriate design earth pressures. The surcharge due to traffic Toads behind a wall can typically be accounted for by adding a uniform pressure equal to 2 feet multiplied by the above active fluid density. Heavy construction equipment should not be operated behind retaining and foundation walls within a distance equal to the height of a wall, unless the walls are designed for the additional lateral pressures resulting from the equipment. The wall design criteria assume that the backfill will be well -compacted in lifts no thicker than 12 inches. The compaction of backfill near the walls should be accomplished with hand -operated equipment to prevent the walls from being overloaded by the higher soil forces that occur during compaction. Retaining Wall Backfill Backfill placed behind retaining or foundation walls should be coarse, free -draining, structural fill containing no organics. This backfill should contain no more than 5 percent silt or clay particles and have no gravel greater than 4 inches in diameter. The percentage of particles passing the No. 4 sieve should be between 25 and 70 percent. For increased protection, drainage composites should be placed along cut slope faces, and the walls should be backfilled with pervious soil. The purpose of these backfill requirements is to ensure that the design criteria for a retaining wall are not' exceeded because of a build-up of hydrostatic pressure behind the wall. The top 12 to 18 inches of the backfill should consist of a compacted, relatively impermeable soil or topsoil, or the surface should be paved. The ground surface must also slope away from backfilled walls to reduce the potential for surface water to percolate into the backfill. The sub -section entitled General Earthwork and Structural Fill contains recommendations regarding the placement and compaction of structural fill behind retaining and foundation walls. The above recommendations are not intended to waterproof the below -grade walls. If some seepage through the walls or moist conditions are not acceptable, damp -proofing or waterproofing should be provided. This could include limiting cold -joints and wall penetrations, and possigly using bentonite panels or membranes on the outside of the walls. Applying a thin coat of asphalt emulsion is not considered waterproofing, but it will only help to prevent. moisture, generated from water vapor or capillary action, from seeping through the concrete. GEOTECH CONSULTANTS, INC. Johnson Braund Design Group, Tnc. December 2, 1997 • JN 97412 Page 6 Rockeries We anticipate that rockeries may be used in the site development. A rockery is not intended to function as an engineered structure to resist lateral earth pressures, as a retaining wall would do. The primary function of a rockery is to cover the exposed, excavated surface and thereby retard the erosion process. We recommend limiting rockeries to a height of 6 feet and placing them against only dense, competent, native soil. The construction of rockeries is, to a Targe extent, an art not entirely controllable by engineering methods and standards. It is imperative that rockeries, if used, are constructed with care and in a proper manner by an experienced contractor with proven ability in rockery construction. The rockeries should be constructed with hard, sound, durable rock in accordance with accepted local practice. Soft rock, or rock with a significant number of fractures or inclusions, should not be used, in order to limit the amount of maintenance and repair needed over time. Provisions for maintenance, such as access to the rockery, should be considered in the design. In general, we recommend that rockeries have a minimum dimension of one-third the height of the slope cut above them. Tiered rockeries are not recommended, unless there is sufficient space to construct upper tiers that do not exert lateral pressure on the lower tiers. The base of a tiered rockery's upper wall should be set back from the rear of the lower rocks an amount equal to the height of the lower tiers. Excavations and Slopes Excavation slopes should not exceed the limits specified in local, state, and national government safety' regulations. Temporary cuts to a depth of about 4 feet may be attempted vertically in unsaturated soil, if there are no indications of slope instability. Based upon Washington Administrative Code (WAC) 296, Part N, the soil type at the subject site would be classified as Type A. Therefore, temporary cut slopes greater than 4 feet in height cannot be excavated at an inclination steeper than 0.75:1 (Horizontal:Vertical), extending continuously between the top and the bottom of a cut. The above recommended temporary slope inclination is based on what has been successful at other sites with similar soil conditions. Temporary cuts are those that will remain unsupported for a relatively short duration to allow for the construction of foundations, retaining walls, or utilities. Temporary cut slopes should be protected with plastic sheeting during wet weather. The cut slopes should also be backfilled or retained as soon as possible to reduce the potential for instability. Please note that loose soil and sand can cave suddenly and without warning, especially where there is groundwater seepage. Utility contractors should be made especially aware of this potential danger. All permanent cuts into native soil should be inclined no steeper than 2:1 (H:V). Fill slopes should not be constructed with an inclination greater than 2:1 (H:V). .To reduce the potential for shallow sloughing, fill must be compacted to the face of these slopes. This could be accomplished by overbuilding the compacted fill and then trimming it back to its final inclination. Water should not be allowed to flow uncontrolled over the top of any temporary or permanent slopes. Also, all permanently exposed slopes should be seeded with an appropriate species of vegetation to reduce erosion and improve the stability of the surficial layer of soil. GEOTECH CONSULTANTS, INC. Johnson Braund Design Group, nc. December 2, 1997 Drainage Considerations JN 97412 Page 7 We recommend the use of footing drains at the base of footings, where (1) crawl spaces or basements will be below a structure, (2) a slab is below the outside grade, or (3) the outside grade does not slope downward from a building. Drains should also be placed at the base of all backfilled, earth -retaining walls. These drains should be surrounded by at least 6 inches of 1 -inch - minus, washed rock and then wrapped in non -woven, geotextile filter fabric (Mirafi 140N, Supac 4NP, or similar material). At its highest point, a perforated pipe invert should be at least as low as the bottom of the footing, and it should be sloped for drainage. Drainage should also be provided inside the footprint of a structure, where (1) a crawl space will slope or be lower than the surrounding ground surface, (2) an excavation encounters significant seepage, or (3) an excavation for a building will be close to the expected high groundwater elevations. Since groundwater was encountered in Test Pit 1, it is likely that groundwater will be encountered during the excavation and that some interior foundation/slab drainage will be necessary. We can provide recommendations for interior drains, should they become necessary, during excavation and foundation construction. All roof and surface water drains must be kept separate from the foundation drain system. A typical drain detail is attached to this report as Plate 6. For the best Tong -term performance, perforated PVC pipe is recommended for all subsurface drains. If seepage is encountered in an excavation, it should be drained from the site by directing it through drainage ditches, perforated pipe, or French drains, or by pumping it from sumps interconnected by shallow connector trenches at the bottom of the excavation. The excavation and site should be graded so that surface water is directed off the site and away from the tops of slopes. Water should not be allowed to stand in any area where foundations, slabs, or pavements are to be constructed. Final site grading in areas adjacent to the buildings should slope away at least 2 percent, except where the area is paved. Additionally, a drainage swale should be provided upslope of the buildings to intercept surface run-off and direct it into the storm drains except where there is pavement adjacent to the buildings. Water from roof, storm water, and foundation drains should not be discharged onto slopes; it should be tightlined to a suitable outfall located away from any slopes. Pavement Areas All pavement sections may be supported on competent, native soil or on structural fill, provided the upper foot of these soils can be compacted to a 95 percent density and the soils are in a stable, non -yielding condition at the time of paving. Granular structural fill or fabric may be needed to stabilize soft, wet, or unstable areas. We recommend using Supac 5NP, manufactured by Phillips Petroleum Company, or a non -woven fabric with equivalent strength and permeability characteristics.. In most instances where unstable subgrade conditions are encountered, 12 inches of granular, structural fill will stabilize the subgrade,, except for very soft areas where additional fill could be required. The subgrade should be evaluated by Geotech Consultants, Inc., after the site is stripped and cut to grade. Recommendations for the compaction of structural fill beneath pavements are given in a later sub -section entitled General Earthwork and Structural Fill. The performance of site pavements is directly related to the strength and stability of the underlying subgrade. GEOTECH CONSULTANTS, INC. • Johnson Braund Design Group, Inc. December 2, 1997 JN 97412 Page 8 The pavement for lightly -loaded traffic and parking areas should consist of 2 inches of asphalt concrete (AC) over 4 inches of crushed rock base (CRB) or 3 inches of asphalt -treated base (ATB). We recommend providing heavily -loaded areas with 3 inches of AC over 6 inches of CRB or 4 inches of ATB. Heavily -loaded areas are typically main driveways, dumpster sites, or areas with truck traffic. The pavement section recommendations and guidelines presented in this report are based on our experience in the area and on what has been successful in similar situations. Some maintenance and repair of limited areas can be expected. To provide for a design without the need for any repair would be uneconomical. General Earthwork and Structural Fill All building and pavement areas should be stripped of surface vegetation, topsoil, organic soil, and other deleterious material. The stripped or removed materials should not be mixed with any materials to be used as structural fill, but they could be used in non-structural areas, such as landscape beds. Structural fill is defined as any fill placed under a building, behind permanent retaining or foundation walls, or in other areas where the underlying soil needs to support loads. All structural fill should be placed in horizontal lifts with a moisture content at, or near, the optimum moisture content. The optimum moisture content is that moisture content that results in the greatest compacted dry density. The moisture content of fill is very important and must be closely controlled during the filling and compaction process. The allowable thickness of the fill lift will depend on the material type selected, the compaction equipment used, and the number of passes made to compact the lift. The loose lift thickness should not exceed 12 inches. We recommend testing the fill as it is placed. If the fill is not compacted to specifications, it can be recompacted before another lift is placed. This eliminates the need to remove the fill to achieve the required compaction. The following table presents recommended relative compactions for structural fill: LOCATION OF FILL PLACEMENT MINIMUM RELATIVE COMPACTION Beneath footings, slabs or walkways Behind retaining walls Beneath pavements 95% 90% 95% for upper 12 inches of subgrade; 90% below that level Where: Minimum Relative Compaction is the ratio, expressed in percentages, of the compacted dry density to the maximum dry density, as determined In accordance with ASTM Test Designation D 1557-78 (Modified Proctor). GEOTECH CONSULTANTS, INC. Johnson Braund Design Group, Inc. • December 2, 1997 Use of On -Site Soil JN 97412 Page 9 If grading activities take place during wet weather, or when the silty, on-site soil is wet, site preparation costs may be higher because of delays due to rain and the potential need to import granular fill. The on-site soil is generally silty and therefore moisture -sensitive. Grading operations will be difficult during wet weather, or when the moisture content of this soil exceeds the optimum moisture content. The moisture content of the silty, on-site soil must be at, or near, the optimum moisture content, as the soil cannot be consistently compacted to the required density when the moisture content is significantly greater than optimum. The on-site silty sands underlying the topsoil and above the groundwater seepage area could be used as structural fill, if grading operations are conducted during hot, dry weather, when drying the wetter soil by aeration is possible. During excessively dry weather, however, it may be necessary to add water to achieve the optimum moisture content. Moisture -sensitive soil may also be susceptible to excessive softening and "pumping" from construction equipment, or even foot traffic, when the moisture content is greater than the optimum moisture content. It may be beneficial to protect subgrades with a layer of imported sand or crushed rock to limit disturbance from traffic. Ideally, structural fill that will be placed in wet weather should consist of a coarse, granular soil with a silt or clay content of no more than 5 percent. The percentage of particles passing the No. 200 sieve should be measured from that portion of soil passing the three -quarter -inch sieve. The silts and clays are not suitable for structural fill, even in the pavement areas. The wet sands found in Test Pit 1 are also not suitable for structural fill. LIMITATIONS The analyses, conclusions, and recommendations contained in this report are based on site conditions as they existed at the time of our exploration and assume that the soil encountered in the test pits is representative of subsurface conditions on the site. If the subsurface conditions encountered during construction are significantly different from those observed in our explorations, we should be advised at once so that we can review these conditions and reconsider our recommendations where necessary. Unanticipated soil conditions are commonly encountered on construction sites and .cannot be fully anticipated by merely taking soil samples in test pits. Subsurface conditions can also vary between exploration locations. Such unexpected conditions frequently require making additional expenditures to attain a properly constructed project. It is recommended that the owner consider providing a contingency fund to accommodate such potential extra costs and risks. This is a standard recommendation for all projects. This report has been prepared for the exclusive use of Johnson Braund Design Group, Inc., Pacific Engineering, and their representatives for specific application to this project and site. Our recommendations and conclusions are based on observed site materials, and selective laboratory testing and engineering analyses. Our conclusions and recommendations are professional opinions derived in accordance with current standards of practice within the scope of our services and within budget and time constraints. No warranty is expressed or implied. The scope of our GEOTECH CONSULTANTS, INC. • Johnson Braund Design Group, Inc. • December 2, 1997 JN 97412 Page 10 services does not include services related to construction safety precautions, and our recommendations are not intended to direct the contractor's methods, techniques, sequences, or procedures, except as specifically described in our report for consideration in design. We recommend including this report, in its entirety, in the project contract documents so the contractor may be aware of our findings. ADDITIONAL SERVICES Geotech Consultants, Inc. should be retained to provide geotechnical consultation, testing, and observation services during construction. This is to confirm that subsurface conditions are consistent with those indicated by our exploration, to evaluate whether earthwork and foundation construction activities comply with the general intent of the recommendations presented in this report, and to provide suggestions for design changes in the event subsurface conditions differ from those anticipated prior to the start of construction. However, our work would not include the supervision or direction of the actual work of the contractor and its employees or agents. Also, job and site safety, and dimensional measurements, will be the responsibility of the contractor. The following plates are attached to complete this report: Plate 1 Vicinity Map Plate 2 Site Exploration Plan Plates 3 - 5 Test Pit Logs Plate 6 Footing Drain Detail We appreciate the opportunity to be of service on this project. If you have any questions, or if we may be of further service, please do not hesitate to contact us. JRF:mmm Respectfully submitted, GEOTECH CONSULTANTS, INC. 1 EXPIRES 8/-17/ if James R. Finley, P.E. Principal GEOTECH CONSULTANTS, INC. 2,91 ,N Lel� 131 r \' I ) ; \� ,� tiZ' P A" /IA\`��Coy 9'QJ, v J isr�° S T ,STO '��~ < a,� ��-� .�� 5, �;�"., /Jo,N �� s uzn0 ST G%y 5 133R0 ,y0 � r�i�� x ®-t5�� ..- tNr»sr 13if 5TH i S7 3Av 3400 o S 136TH z Q }li < t £ SOUTHGATE ` y0 < PARK ._r,^ 1 x 15 S t '�.7, ° $r ' .� 7 emr ■,� it a wot ,.r" 1 �,s,+r ♦ iy FOSTER ; °ea i ` nIN G ,. 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I DR 11 ti `cP 0 • 173R0 5 17250 PL t CORPORA71��1 \ < ST `r • ORS MINKLER 175TH r, - it y PLAN' 3'� BLVD p ST f PARkH.IY t 176TH �" `l' �Ii ♦ .1 ST 1' , P1AZA HiILANlbjD I � a 5 177TH ST '^ ' t; r�", BOW . 1 ., ' LAKE , _ ''''' PK 178TH i - 8 ' SAXON DR S 1 7TH 'Si s t,d,n am ., 4300 .S Ss"' ',1•139D• -�'+ 5_ .�®�� t < 1 _ TRILAND "JR o i 2� 9 e 178TH ST `J` .,,o � � 5 179TH GEOTECH CONSULTANTS VICINITY MAP 51st AVENUE S NEAR S 151st STREET TUKWILA, WA .dolt No.r Dole: Lopped By: Pole: 97412 NOV 1997 1 / 1' 1 I PROPOSED OUILDINGS / l / / i // 1 / 0 TP -4 ITP -311 / 1 / / / I / / / / I / I 11 I / LEGEND Q APPROXIMATE TEST PIT LOCATIONS SITE EXPLORATION PLAN 51st AVENUE S NEAR S 151st STREET TUKWILA. WA ✓o0 No.' 97412 NOV 1997 Plots 2 isz 40. cox v Go , • J • • TEST PIT 1 Description 10 15 5 10 15 opsoil Brown, silty SAND, fine- to medium -grained, with some gravel, very moist, medium - dense to dense - becomes very silty to fine-grained, sandy SILT ui Brown -gray, silty, medium -grained SAND, wet to saturated, medium -dense to dense - becomes more silty with laminae 1111 ML Blue -gray, clayey SILT, moist, hard * Test Pit was terminated at 12 feet on November 12, 1997. * Moderate groundwater seepage was observed from 5.5 to 9 feet during excavation. * No caving observed during excavation. TEST PIT 2 9e.,4woe Description OMNI IWO WIN .11111101 SM Topsoil - Brown, silty SAND, with organics Brown, silty SAND, with gravel, some staining, very moist, medium -dense to dense - occasional thin, hard, silt layers (Till like) - becomes very dense - occasional boulder (-18" diameter) and occasional Targe cobbles Blue -gray SILT, with clay, moist, hard * Test Pit was terminated at 12 feet on November 12, 1997. * No groundwater observed during excavation. * No caving observed during excavation. TEST PIT LOG 51st Avenue South near South 151st Street Tukwila, Washington Job No: 97412 Date: 'Logged by: November 97 DBG Plate: 3 ///,.6 9 G° (S°Y TEST PIT 3 • • Description 10 15 10 15 „III, opsoil - Dark brown, silty SAND, with organics Brown, silty SAND, fine- to medium -grained, with some gravel, very moist, medium -dense - becomes very silty Brown, fine-grained SAND, with silt, moist, medium -dense to dense BIM SM * Test Pit was terminated at 12 feet on November 12, 1997. * No groundwater observed during excavation. * No caving observed during excavation. TEST PIT 4 9 CP ES J Description MIS MIN Topsoil - Brown. silty SAND. with oraanicg Brown, silty, gravelly SAND, fine-grained, moist, dense - becomes Tess gravelly 1111 ML Tan to blue -gray SILT, moist, hard, massive * Test Pit was terminated at 12 feet on November 12, 1997. * No groundwater observed during excavation. * No caving observed during excavation. TEST PIT LOG 51st Avenue South near South 151st Street Tukwila, Washington Job No: 97412 Date: 'Logged by: November 97 DBG Plate: 4 5 10 15 .0,,e0t( Sex SCP CP ,s0Yti • TEST PIT 5 Description Topsoil - Dark brown, silty SAND, with organics SM ML Brown, silty, gravelly SAND, moist, dense - large boulder at 6.5 feet 'Gray SILT/CLAY, moist, hard (becomes sandy at very bottom) * Test Pit was terminated at 7.5 feet on November 12, 1997. * No groundwater observed during excavation. * No caving observed during excavation. TEST PIT LOG 51st Avenue South near South 151st Street Tukwila, Washington Job No: 97412 Date: 'Logged by: November 97 DBG Plate: 5 • • Slope boc,Kil/ owq from foundation. WASHED ROCK m BACKFILL See text for requirements. NONWOVEN GEOTEXTILE FILTER .FABRIC TIGHTL/NE ROOF DRAIN Do not coned Ib tooling drain. SLAB VAPOR BARRIER ♦'• ,f '• ' •'• w .�,. 4 min. FREE -DRAIN/NG SAND/GRAVEL 4" PERFORATED HARD PVC .P/PE Invert a1 /east as low as fooling and/or [growl space. S/ape to drain. Place weepho/es downward. Alf GEOTECH CONSULTANTS, INC. FOOTING DRAIN DETAIL 51st Avenue South near South 151st Street Tukwila, Washington Job No: 97412 Date: November 97 Plate: 6 • • A. BACKGROUND 1. Name of proposed project, if applicable: 51st Avenue Office Building 2. Name of applicant: 51st Avenue LLC 3. Address and phone number of applicant and contact person: 130 Andover Park East, Suite 301 Seattle, WA 98188 (206) 431-7960 Contact: Mel Easter Johnson Braund Design Group, Inc. (206) 431-7960 4. Date checklist prepared: December 19, 1997 5. Agency requesting checklist: City of Tukwila, WA 6. Proposed timing or schedule (including phasing, if applicable): E9r7•oc 3.9' REC'5IIV D DEC 2 2 1997 COMMUNITY DEVELOPMENT Applicant would like to begin construction in April, 1998. Project is targeted for completion in Fall of 1998. 7. Do you have any plans for future additions, expansion, or further activity related to or connected with this proposal? If yes, explain. No. 8. List any environmental information you know about that has been prepared, or will be prepared, directly related to this proposal. Geotechnical study - see attached copy. Traffic Analysis - see attached copy. 9. Do you know whether applications are pending for governmental approvals of other proposals directly affecting the property covered by your proposal? If yes, explain. None Known. 10. List any government approvals or permits that will be needed for your proposal, if known. SEPA Determination Land Altering Permit Design Review Approval Building Permit Retaining Wall Permit 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. (Lead agencies may modify this form to include additional specific information on project description.) The proposed development consists of a 2 -story wood fframe office building, containing undivided commercial office space, on an 1.09 acre site. The project also includes a small outbuilding for storage and parking for 64 vehicles. -1- • • 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 applications related to this checklist. The subject site is located on the east side 51st Avenue, west of Interstate 5, in the city of Tukwila. The parcel fronts on 51st Avenue, but because of steep slopes and an existing 12' high retaining wall, access to the parcel is from S. 151st St., north of the parcel, through a 30' easement. To the south of the site is an office building; to the west of the site, across 51st Ave., is single family zoned (undeveloped) property; to the north and east of the site are both single and multiple family residences.. See attached vicinity map and legal description. -2- • • B. ENVIRONMENTAL ELEMENTS TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 1. Earth a. General description of the site (circle one): Flat, rolling, hilly, steep slopes, mountainous, other b. What is the steepest slope on the site (approximate percent slope)? The steepest slopes of the site are 50% for an area of 300 S.F., and are located in the center of the site. Generally, the slopes on the site range from 6-15%. 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. See attached geotechnical report by Geotech Consultants, Inc. (December 2, 1997). d. Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe. None known. e. Describe the purpose, type, and approximate quantities of any filling or grading proposed. Indicate source of fill. Approx. 2300 c.y. will be cut and filled on site for a balanced condition. f. Could erosion occur as a result of clearing, construction, or use? If so, generally describe. g. Yes. Earthwork operations will expose soil to potential erosion during clearing/grading process, depending on weather conditions. About what percent of the site will be covered with impervious surfaces after project construction (for example, asphalt or buildings)? Impervious surface coverage will be approximately 34,400 S.F. or 72% of the total site area. h. Proposed measures to reduce or control erosion, or other impacts to the earth, if any: A temporary erosion control plan will be prepared in accordance with city standards, to include silt fencing and settling pinds. Summer construction is anticipated to help further minimize erosion potential. 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 approximate quantities if known. Some dust will be generated during construction. Automobile emissions will increase slightly when project is complete b. Are there any off-site sources of emissions or odor that may affect your proposal? If so, generally describe. None known. -3- • • c. Proposed measures to reduce or control emissions or other impacts to air, if any: Watering the site as necessary to control dust during construction. Automobile usage to the site is expected to be minimal. 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. None. 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. No. 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. None proposed. 4) Will the proposal require surface water withdrawals or diversions? Give general description, purpose, and approximate quantities if known. No. 5) Does the proposal lie within a 100 year flood plain? If so, note location on the site plan. No. 6) Does the proposal involve any discharges of waste materials to surface. waters? If so, describe the type of waste and anticipated volume of discharge. No. b. Ground: 1) Will ground water be withdrawn, or will water be discharged to ground water? Give general description, purpose, and approximate quantities if known. No. 2) Describe waste material that will be discharged into the ground from septic tanks or other sources, 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 of houses to be served (if applicable), or the number of animals or humans the system(s) are expected to serve. None. • c. Water Runoff (including storm water): 1) Describe the source of runoff (including storm water) and method of collection and disposal, if any (include quantities, if known). Where will this water flow? Will this water flow into other waters? If so, describe. Surface water runoff will be generated only from rainfall diverted from impervious surfaces such as building roofs and paved areas. All surface water runoff will be collected on site, conveyed to a detention facility, and then discharged to an off-site receiving system. 2. Could waste materials enter ground or surface waters? If so, generally describe. No. d. Proposed measures to reduce or control surface, ground, and runoff water impacts, if any: The project will implement a storm water management system, including an oil/water separator, coalescing plate oil/water separator and a detention facility. These systems will be designed in accordance with City of Tukwila standards. 4. Plants a. Check or circle types of vegetation found on the site: X deciduous tree: alder, maple, aspen, other evergreen tree: fir, cedar, pine, other shrubs X grass pasture crop of grain wet soil plants: cattail, buttercup, bullrush, skunk cabbage, other water plants: water lily, eelgrass, milfoil, other other types of vegetation b. What kind and amount of vegetation will be removed or altered? All existing vegetation on the site will be removed. c. List threatened or endangered species known to be on or near the site. None known. d. Proposed landscaping, use of native plants, or other measures to preserve or enhance vegetation on the site, if any: Ornamental landscaping, including the use of native plants, will be incorporated throughout the developed property. 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: hawk, heron, eagle, songbirds, other: mammals: deer, bear, elk, beaver, other: fish: bass, salmon, trout, herring, shellfish, other: b. List any threatened or endangered species known to be on or near the site. None known. c. Is the site part of a migration route? If so, explain. None known. -5- • • d. Proposed measures to preserve or enhance wildlife, if any: None. 6. Energy and Natural Resources a. What kinds of energy (electric, natural gas, oil, wood stove, solar) will be used to meet the completed project's energy needs? Describe whether it will be used for heating, manufacturing, etc. Electric energy and/or natural gas will be used for heating, lighting and air conditioning. b. Would your project affect the potential use of solar energy by adjacent properties? If so, generally describe. No. 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: The building will comply with current Washington State energy code requirements for glazing and insulation. 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. None known. 1) Describe special emergency services that might be required. None known. 2) Proposed measures to reduce or control environmental health hazards, if any: None. b. Noise 1) What types of noise exist in the area which may affect your project (for example: traffic, equipment operation, other)? Traffic noise from Interstate Highway 5 (to the east of the site) will be audible on site. 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: traffic, construction, operation, other)? Indicate what hours noise would come from the site. Short term: Construction noise will occur during daylight hours for a period of 4 to 5 months. Long term: Traffic noise will occur during arrivals and departures from the site. 3) Proposed measures to reduce or control noise impacts, if any: Limit construction activity to daylight hours. 8. Land and Shoreline Use a. What is the current use of the site and adjacent properties? The site is currently vacant. The property to the south has an office building and associated parking; to the east and north are single and multiple family residences; to the west is 51st Avenue and undeveloped property. -6- • • b. Has the site been used for agriculture? If so, describe. Not known. c. Describe any structures on the site. None. d. Will any structures be demolished? If so, what? None. e. What is the current zoning classification of the site? O - Office. f. What is the current comprehensive plan designation of the site? O - Office. If applicable, what is the current shoreline master program designation of the site? N/A. g. h. Has any part of the site been classified as an "environmentally sensitive" area? If so, specify. No. i. Approximately how many people would reside or work in the completed project? Approximately 40 to 50 people will work in the completed office building. Approximately how many people would the completed project displace? None. k. Proposed -measures to avoid or reduce displacement impacts, if any: None. I. Proposed measures to ensure the proposal is compatible with existing and projected land uses and plans, if any: The proposal is consistent with the "0" zoning designation. The office building is a permitted use within this zone and comprehensive plan designation. 9. Housing a. Approximately how many units would be provided, if any? Indicate whether high, middle, or low-income housing. None. b. Approximately how many units, if any, would be eliminated? Indicate whether high, middle, or low-income housing. None. c. Proposed measures to reduce or control housing impacts, if any: None. • • 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? Structure Height - approximately 35 feet. Exterior Materials - CMU block with brick and E.I.F.S. banding, standing seam metal roof, and painted metal railings. b. What views in the immediate vicinity would be altered or obstructed? None known. c. Proposed measures to reduce or control aesthetics impacts, if any: Use of architectural styling and building materials which will be compatible with the architecture in the neighborhood. 11. Light and Glare a. What type of light or glare will the proposal produce? What time of day would it mainly occur? Minimal glare from exterior lights during evening hours. b. Could light or glare from the finished project be a safety hazard or interfere with views? No. c. What existing off-site sources of Tight or glare may affect your proposal? None known. d. Proposed measures to reduce or control light and glare impacts, if any: Use of shielded light fixtures. 12. Recreation a. What designated and informal recreational opportunities are in the immediate vicinity? None. b. Would the proposed project displace any existing recreational uses? If so, describe. No. c. Proposed measures to reduce or control impacts on recreation, including recreation opportunities to be provided by the project or applicant, if any: The site plan will include a landscaped, outdoor lunch area for employees. 13. Historic and Cultural Preservation a. Are there any places or objects listed on, or proposed for, national, state, or local preservation registers known to be on or next to the site? If so, generally describe. None known. • b. Generally describe any landmarks or evidence of historic, archaeological, scientific, or cultural importance known to be on or next to the site. None known. c. Proposed measures to reduce or control impacts, if any: None. 14. Transportation a. Identify public streets and highways serving the site, and describe proposed access to the existing street system. Show on site plans, if any. The site has frontage on 51st Avenue. Because of steep slopes and an existing retaining wall along that property line, however, access to the site is from S. 151st St. through a 30' easement that leads from the northeast corner of the property. b. Is site currently served by public transit? If not, what is the approximate distance to the nearest transit stop? No - Approx. 1/2 mile to the nearest bus stop. c. How many parking spaces would the completed project have? How many would the project eliminate? Parking for (64) vehicles will be included on-site. No parking spaces will be eliminated. 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). None known. e. Will the project use (or occur in the immediate vicinity of) water, rail, or air Transportation? If so, generally describe. No. f. How many vehicular trips per day would be generated by the completed project? If known, indicate when peak volume would occur. g. See attached Traffic Analysis. Proposed measures to reduce or control transportation impacts, if any: None. 15. Public Services a. Would the project result in an increased need for public services (for example: fire protection, police protection, health care, schools, other)? If so, generally describe. Minor increase in potential fire protection, emergency services and police protection. b. Proposed measures to reduce or control direct impacts on public services, if any: None proposed. • • 16. Utilities a. Circle utilities currently available at the site: electricity, natural gas, water, refuse service, telephone, sanitary sewer, cable tv, 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. Water - (Water Distrist 125) An 8" water main will be extended from the existing city mainline for fire protection and domestic use. Sewer - (ValVue Sewer District) An 8" sewer main exists on site. Power - Provided by Puget Sound Energy. Gas - Provided by Puget Sound Energy. Telephone - Provided by U.S. West. Cable - TCI Signature: 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 oryyillfI lack of full disclosure on my part. /6' CI1/ q7 Proponent: Name Printed: Date: A:721 sepa/envcklist D. PROPERTY OWNER DECLARATION The undersigned makes the following statements based upon personal knowledge: 1. I am the current owner of the property which is the subject of this application. 2. All statements contained in the application are true and correct to the best of my knowledge. 3. The application is being submitted with my knowledge and consent. 4. I understand that conditions of approval, which the City and applicant have jointly agreed may not be completed prior to final approval of the construction (e.g., final building permit approval) will be incorporated into an agreement to be executed and recorded against the property prior to issuance of any construction permits. I declare under penalty of perjury under the laws of the State of Washington and the United States of America that the foregoing statement is true and correct. EXECUTED at (city), �r4,Or� 13 ,1 sgl_. (state), on 4/l44 Rb .X6 • % ANl1'iq E" Pobt 5 (Print Name) / — 5Sf v- -So , (Address) co,)V-13L/ (Phone Number) Y9,4tAte/1.4 Use additional sheets as needed for all property owner signatures. • LEGAL DESCRIPTION PARCEL A THE SOUTH 22 FEET OF LOT, AND ALL OF LOT 10, YOUNG'S HALF ACRE TRACTS, ACCORDING TO THE PLAT THEREOF RECORDED IN VOLUME 16 OF PLATS, PAGE 37, ;RECORDS OF KING COUNTY, WASHINGTON. TOEGETHER WITH VACATED SOUTH 15ND STREET ADJOINING, WHICH ATTACHED THERETO BY OPERATION OF LAW. PARCEL B LOT 3 OF CITY OF TUKWILA SHORT PLAT NO. 78-35-55 AS RECORDED UNDER RECORDING NON 7901250881, RECORDS OF KING COUNTY, WASHINGTON. TOGETHER WITH AND EASEMENT OVER THE EAST 30 FEET OF LOTS 1 AND 2 OF CITY OF TUKWILA SHORT PLAT NO. 78-34-55, RECORDED UNDER RECORDING NO. 7901250881. PARCEL C LOT 2 OF CITY OF TUKWILA SHORT PLAT NO. 78-34-55 AS RECORDED UNDER RECORDING NO. 7901250881, RECORDS OF KING COUNTY, WASHINGTON. TOGETHER WITH AND SUBJECT TO AN EASEMENT FOR INGRESS, EGRESS AND UTILITIES OVER THE EAST 30 FEET OF LOTS 1 AND 2 OF CITY OF TUKWILA SHOT PLAT NO. 78-34-55, RECORDED UNDER RECORDING NO. 79-01250881. ALL SITUATE IN THE COUNTY OF. KIING, STATE OF WASHINGTON. TO: • City of Tukwila John W. Rants, Mayor Department of Public Works Ross A. Earnst, P. E., Director Michael Jenkins Planning Dept. FROM: Gary Barnett Public Works Dept. RE: 51st Ave. South Office Building 15150 - 51st Ave South E97-0039 & L97-0079 DATE: February 5, 1997 The Public Works Department has the following comments related to this project. SEPA 1. Based on field review, our analysis, and reviewing the traffic report prepared by TP&E the Public Works Department recommends the following traffic mitigation requirement: South 151st Street is a sub -standard roadway lacking curb, gutter, sidewalk, storm drainage shoulders, and street lighting. To improve pedestrian and vehicular safety the applicant shall install a luminaire on the existing power pole across from the access point. Additionally a paved shoulder shall be constructed from the access point to South 51st Ave. South 151st Street shall be shifted northerly approaching the intersection, the existing pavement repaired and re -paved to increase pavement width for vehicles and pedestrians. This shift northerly will eliminate cutting into the existing landscaped slope to the north. 2. The applicant proposes to grade the westerly portion of the site by cutting the existing slope. This cut is into the toe of a much larger slope that is retained by an engineered concrete block wall. The applicant shall provide acceptable evidence of gross slope stability by preparing a geotechnical report that evaluates the proposed grading at the west side of the site in context of the overall slope stability. The analysis shall use information and assumptions in the Geo - engineers February 8, 1995 Geotechnical Engineering Services Report for 51st Ave. South Bridge over 154th Street. The applicant's engineer shall provide supplementary analysis and information as necessary to demonstrate that the proposed site grading is compatible with sound geotechnical practices. Anticipated Building Permit Conditions 1. Traffic mitigation fees will be required of the applicant as condition of the building permit. The City's concurrence ordinance will be the basis for this traffic mitigation fee. 6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • Phone: (206) 433-0179 • Fax (206) 431-3665 2. In consideration of the pavement repairs identified in item one above, the applicant will be credited $1,500.00 towards traffic mitigation fees. Thank you for the opportunity to review the proposed development. With these conditions the proposed project should have no adverse impact. Please call me if you have any questions. GB:tkf cf: Joanna Spencer