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Permit MI99-0156 - CITY OF TUKWILA - RETAINING WALLS
F ' � � aty t a :�fr,`!. ,. � ".?,...F.r�: Z,o-'�;fcF•.�.,'.. ?�czin ;r;,R�t'.: 3:r:.': k!Sf•' � st�Y.0 frt?'?'i!!f.;5'.9,!Yi MI99 -0156 15447 65t'' Ave. So. City of Tukwila ( (206) 431 -3670 Community Development / Public Works • 6300 Southcenter Boulevard, Suite 100 • Tukwila, Washington 98188 MISCELLANEOUS PERMIT WARNING: IF CONSTRUCTION BEGINS BEFORE APPEAL PERIOD EXPIRES. APPLICANT IS PROCEEDING AT THEIR OWN RISK. Parcel No: 359700 -0320 Address: 15447 65 AV S Suite No: Location: Category: OTHR Type: MISCPERM Zoning: 0 Const Type: Gas /Elec.: Units: 000 Setbacks: North: Water: N/A Wetlands: .0 South: .0 E Sewer: N/A Slopes: Y Contractor License No: PHILIESO44LF Permit No: Status: Issued: Expires: MI99 -0156 ISSUED 09/14/1999 03/12/2000 Occupancy: UBC: 1997 Fire Protection: ast: .0 West: .0 OCCUPANT CITY OF TUKWILA 15447 65 AV S, TUKWILA WA 98188 OWNER CITY OF TUKWILA 6200 SOUTHCENTER BLVD, TUKWILA WA 98188 CONTACT BOB GIBERSON 6300 SOUTHCENTER BL, TUKWILA WA 98188 CONTACT SCOTT MOORE Phone: 206 - 433 -0179 6300 SOUTHCENTER BL; STE 100, TUKWILA, WA 98188 CONTRACTOR PHILIP ENVIRONMENTAL SRVC CORP Phone: 425- 227 -6167 PO BOX 3552, SEATTLE, WA 98124 **********************************************.******* * ** ** * * * ** * ** * * * * * *** **** * * * * *,1 Permit Description: CONSTRUCT MODULAR BLOCK RETAINING WALLS. ****************************************************** * * ** * * * * * * * * ** ** * * * * * * ** * * * * *1 Construction Valuation: $ 73,000.00 PUBLIC WORKS PERMITS: *(Water Meter Permits Listed Separate) Eng. Appr: Curb Cut /Access /Sidewalk /CSS: N Fire Loop Hydrant: N No: Flood Control Zone: N Hauling: N Start Time: End Time: Land Altering: N Cut: Fill: Landscape Irrigation: N Moving Oversized Load: N Start Time: End Time: Sanitary Side Sewer: N No: Sewer Main Extension: N Private: Public: Storm Drainage: N Street Use: N Water Main Extension: N Private: Public: ****************************************************** * * * * * *** * * * * ** * * * * * * **r * * * * * * *A TOTAL DEVELOPMENT PERMIT FEES: $ 1,190.03 ************ * * * * * * * **r * * * * * * * * * * * * * ** * * * *il ******* c******** *k * **c ** * **r * * * * * * *k * * **c * * * **4 Streams: Phone: Phone: (206)433 -1835 Phone: 206- 433 -0179 Size(in): .00 Permit Center Authorized Signature: I hereby certify that I have read and examined th" s permit and know the same to be true and correct. All provisions of law and ordinances governing this work will be complied with, whether specified herein or not. The granting of this permit does not presume to give authority to violate or cancel the provision of any other state or local laws regulating construction or the performance of work. I am authorized to sign for and obtain this development permit. Signature:_ �/jlv� Print Name:__3Q Q ( i (AOO- Date: 4112 This permit shall become null and void if the work is not commenced within 180 days from the date of issuance, or if the work is suspended or abandoned for a period of 180 days from the last inspection. Crri' OF TU•W.1LA Addres&.: 15447 65 AV Per-arit 14i MU-.7■9•,-6156 Sulte: fenant: Status; ISSUEC Fv•e: MISCPERM APolied: Oe;/16/1999, Par'cel #: .359700-0320 1Ssued: 091141999 A,.4,****4:4****-********lokk**k**kkP**41.b**4t4k4-k.A-kpk*hk44,4*0,W**Or0, Ak0.*0, 0,0,.4 k**,44 ' Permit Conditions: 1. .1\10 changes will pe made to the Is unless approved by the Engineer and the Tulwila_Su)Adina.,-.:0011s)on. 2. AlLpermits. inspectionf.reCOrdandabOoved plans shallbe available at thej00:Site-Orior to the any t.on- cr uc t ion . These u me n t,s a e to be n in ta ed;:; and avail -7. le until fjnaT'inspect,Aot>appr,OVal Sub9rade preparatiOninOUdiii4',OraihageecaVatiOn.., compactionand T 1 1 1 reduirementhal 1 conformstritt),y with - 'yeCommendatiOnS:gien 4 All const'ruction•to tte' done:inconformanCe:.withapProved plans.and reo6Wements o1 the cu ,Editton) a amended, Unifor-m Mechanical Code (1997::Edit1 OnT, and Washington State EnergYCode,(199? Edition)., 5. yaliAttyHol'Permit. jhe issi4ande of a permit or aporova,1 ot plans, speOlficationsand-,sbmoutatfons*shall strued tobe a pet mit foi..-4>5a-.apb:royal of any of,any of th,e'proviSionS,of:thebv44din4-oode_or: of any other ordipance-of-the-iurisdiCtionNo permit O'retuMingto.., .91Ye'aut1ority.JO'violate,Or Cancel the_proviSions Of OH's. code!, shall" be v,a 1 id. • , • • CITY OF''UKWILA Permit Cente 6300 Southcenter Boulevard, Suite 100 Tukwila, WA 98188 (206) 431 -3670 , , - Miscellaneous Permit Application Application and plans must be complete in order to be accepted for plan review. Applications will not be accepted through the mall or facsimile. Project Name/Tenant: �r r'( WA-u- P 1eww& LoT EX PANS /oA% Value qf Construction: *is, 000 (wM -s wilt Site Address: City State /Zip: 1544-7 G 5TK PrvE - 5. Tax Parcel Number: 35 q71 0320 Property CITY 0 -ruk 1L A GG , A' I C �/V Phone: 03 1 Soo �.. Street Address: City State /Zip: 6200 5Ov"tNcEi<rrvR gout-sows Fax #: Contact Person: ?oE. G115eRsoN,p E. Phone: O1, 11 (ax+. 163 4'3 — 3 Street Address: City State /Zip: S00 SO J TKG6MTEit g LVb ) rnrr. / SO Fax #: 'mil - 3665- Contrac r: .rFtI4.i P ER/VI D,//14 e3Vr4L SVGS. Phone: Street Address: City State /Zip: Qs5 Pots e2- Ati'E- S.W. 'l�oN Fax #: Architect: Phone: Street Address: City State /Zip: Fax #: Engineer: KOTr1 >H Iu EJGi&grewAG �T f Phone: Street Address' City State /Zip: 1445) NE- zRTof tic- so/, sue.z.evve. Fax #: MISCELLANEOUS: PERMIT REVIEW'AND APPROVAL REQUESTTED.:(TO BE'F!l:TED;OUT B.Y,APPLICANT) ;< Description of work to be done: Coivs-rrtVC:r MO kg/LA-it 0410(44 Re5PrAikloi6 Wig- i--L.s" Will there be storage of flammable /combustible hazardous material in the building? ❑ yes ❑ no Attach list of materials and stora.e location on se • arate 8 1/2 X 11 •a•er indicatin. • uantities & Material Safet Data Sheets ■ Above Ground Tanks ■ Antennas /Satellite Dishes ■ Bulkhead /Docks ■ Commercial Reroof ❑ Demolition ❑ ence ❑Mechanical [I Manufactured Housing - Replacement only El Lots Retaining Walls CI Temporary Pedestrian Protection /Exit Systems in Temporary Facilities Tree Cutting APPLICANT, REQUEST, FOR•MISCELLANEOUSPUBL'IC:WORKS PERMITS`y' ❑ Channelization /Striping ❑ Flood Control Zone ❑ Landscape Irrigation ❑ Storm Drainage ❑ Water Meter /Exempt It ❑ Water Meter /Permanent #t ❑ Water Meter Temp # in Miscellaneous ❑ Curb cut/Access /Sidewalk ❑ Fire Loop /Hydrant (main to vault) #: Size(s): ❑ Land Altering: 0 Cut cubic yards 0 Fill cubic yards 0 sq. ft.grading /clearing ❑ Sanitary Side Sewer #: ❑ Sewer Main Extension 0 Private 0 Public ❑ Street Use ❑ Water Main Extension 0 Private 0 Public Size(s): 0 Deduct 0 Water Only Size(s): Size(s): Est, quantity: gal Schedule: ❑ Moving Oversized Load /Hauling MONTHLYSERVIGEBILLINGS;•T.O :. ,, :;; :. :;';;(. ` ' ' Name: Phone: Address: City /State /Zip: 0 Water 0 Sewer 0 Metro 0 Standby WATER METER DEPOSIT/REFUND BILLING :., Name: Phone: Address: City /State /Zip: • Value of Construction - In all cases, • value of construction amount should be entered by the applicant. This figure will be reviewed and is subject to possible revision by the Permit Center to comply with current fee schedules. Expiration of Plan Review - Applications for which no permit is issued within 180 days following the date of application shall expire by limitation. The building official may extend the time for action by the applicant for a period not exceeding 180 days upon written request by the applicant as defined in Section 107.4 of the Uniform Building Code (current edition). No application shall be extended more than once. Date application accepted: g 1v•qa Date aation expires: iiii —ltd_ 21r!is Applicattn fen by: (Initials) I i ALL MISCELLANEOUS PEP'' APPLICATIONS MUST BE SUBM D WITH THE FOLLOWING: DC. 'igtli4I4AW'Vt;i�' LL = E AT A LEGIBLE SCALE AND NEATLY DRAWN ,,,jA .� Dlrji�DINb EPI! IS AND UTILITY PLANS ARE TO BE COMBINED '7' " ARHITECTURALtDRAWINGS REQUIRE ii' if/95) , W4 4INQTON LICENSED ARCHITECT ➢ STRUCTURAL CALCULATIONS AND DRAWINGS REQUIRE STAMP BY WASHINGTON LICENSED STRUCTURAL ENGINEER ➢ CiVIL/SITE PLAN DRAWINGS REQUIRE STAMP BY WASHINGTON LICENSED CIVIL ENGINEER (P.E.) SUBMIT APPLICATION AND RE.QUIRED CHECKLISTS FOR PERMIT REVIEW Above .GOundITatlka/Water'Tanke -'Supported : iirectly,upen grads;.. exceeding: 00 gallons and :a ratio of height to diameter or width . which'e)tceeds'17:'I :..: y Antennas /Satellite Dishes::.. Ubrilit cfiebkliet: 7. Awnings /Canopies -'. No:sigriaga Submit checklist No M -1 Bulkhead /Dock 'Commercial Rerdo Co'rnmercial'Tenant Improvement P,errpit 41.: ' •Submit M =10 Submit checklist No: M -6:: Demolition =''',' Fences- °Over'6'feet'in :Height: Submit chedlkiist''+° Land;Altering/Grading/Preloads ommercial: renantIrnprovementr !ermit: ': SUbm t' checklist-Nof: i' =:1:7 Mechanical'.(Residential & C.ci mmercial);;; Miscellaneous Publ.ictWorks Permitss: 1 t ':1 upmit cligcklist ' hlo ^ ,MLf fiesideritiaLonly.;:H .H. `:; Submit cleoklist ,Manufactured Housing '.(RED.;INSIGNINONLY ti :Submit checklist MovitigOversi ?ed:Load /Hauling.'; Submit chepklist.' .No> M -5' Parkiiig'Lots,: Submit checklist ; No: '`M -4 Residential'Reroof - :,,Exemptwith,folibwing exception'If; roof :structure to be repaIredor replaced Residential Building Permit Subiiiit.checklist':;‘:No: M-E RetaininaWalis .Over 4 feet.in height.: Temporary,; Facilities..: empor'ary Pedestrian Pr'otection/Eidt systems Submit checklist <:> Tree Cutting;r Submit .checklist ❑ Copy of Washington State Department of Labor and Industries Valid Contractor's License. If not available at the time of application, a copy of this license will be required before the permit is issued, unless the homeowner will be the builder OR submit Form H -4, "Affidavit in Lieu of Contractor Registration ". Bullding!.Owner /Authorlied Agent. : )f the applicant is other than the; owner,;registero. d. architect /engineer orcontraator lrcenab by the •State;of. Washington, a notar►zed'letter from the property;owner authorizing. the agent-to submit this permit application,an • obtain: the; permit will be .r'equired as part of this submitfali. •` • I HEREBY CERTIFY THAT I HAVE READ AND EXAMINED THIS APPLICATION AND KNOW THE SAME TO BE TRUE UNDER PENALTY OF PERJURY BY THE LAWS OF THE STATE OF WASHINGTON, AND I AM AUTHORIZED TO APPLY FOR THIS PERMIT. BUILDING,OWNER:OR AU ORIZEDAGENT: Signature: Date: 9/ Welq Print name: BO� Giberso n Phone: 433 ,0I? 1 F ax #: Address: Safi C L vin y cUl'l'trT �(,n City/State/Zip: ;1A1 w*- iit fit .0. • MISCPMT.E d!. y 411/96 �•• 0 } *+**'++***+*+**A++**+* +v*A**+^*/-*a*+aa*x****** LI[Y OF TUKWILA. WA — �(1_ [U AGMIT x*A**a*****^+**°4a**+******+* V*A+°+*+.+***vA+**IVxa*++a I. 8AASIAI Num b er 11 9800 149 A in . 1,1$0.0309/14/9 9 15:19 Yuvmwnt Method: SCOTT ,Notstiun: SCOTT 41U6RE Init: TL8 --.,----.-_.-_-.-'--.---'~__~._-. 'Pemjt WO; � NI99-0156 T.oe: MIS(PEkM MISCELiAMsOUS PERMIT |,aroel No:. 35970070320 Site Address: 15447 65 AV S 'total Fever This Payment 1.190.03 Total ALL Pmt$: 1.i8003 ( Uilanc*: ' . /O ^a^+^*++�+^��«v++*++*++�******«*��a***+****aa+i+^+«+�*+*.*^**�^+ Account Code Desur)otjoo � � _ . Amount 0.00/322.100 BU1I1.U%N6 - NONkES ��� � � ' ' 718.50 ' 000/3.45^V:M PLAN CHECK - NDNNEB 000/386.904 STAT� 81111.. DING SURCHARGE � `� 4.5O ChorS -�--�^.-~--'._, ~- � / ' L�J `\ ^~~~~ --'.�. ~� 1 INSPECTION NO. INSPECTION REC Retain a copy with permit CITY OF TUKWILA BUILDING DIVISION 6300 Southcenter Blvd, #100, Tukwila, WA 98188 rhi4kis)-(c. (206)431 -3670 CP oject: -� ``,� JJ� t t �c�1/ f-'Ctr Komi-at 14 Type of Inspectio�nn: Type F nce. -( rpm 4ddre a IS ei% �P� 7 .� Date called. / 9h O1 CA Kri coupe/9 .'j1Lrd ►7.s. \-`s;E, r ._ Special instructions: . • Date wa ed: // 97 /0/0/ a.m. p.m. Re uester :i J� Ct^ 7r'.. Phone: 20/0 -5 71-- 1p 32.3 Approved per applicable codes. ECorrections recjuired prior to approval. COMMENTS: 1, r O ''OW\ p I��e� rpm ` ,.`49(.--4 � r t .r,;1�i nc, uJ'NI1I1 - 1 - -1 h$4CItied') r CA Kri coupe/9 .'j1Lrd ►7.s. \-`s;E, r ._ i i ( 1, - j 11100 tt (' 1 RuU ( LLUo1i(1 i 11 Sip t-c-)to .40 F *1 (Act Inspector, ' rpm Date: 1r‘` U-0) El $47.00 REINSPECTION FEE REQUIRED. Prior to inspection, fee must be paid at 6300 Southcenter Blvd., Suite 100, Cali to schedule reinspection. INSPECTION NO INSPECTION RECOR<<. Retain a copy with permit CITY OF TUKWILA BUILDING DIVISION 6300 Southcenter Blvd, #100, Tukwila, WA 98188 Wrs 4g -ol Sto PERMIT NO. (206)431 -3670 P j t: Type of inspection: A dress. Date called: ,^,,,...,. -- Special instructions: ` Date wanted: a.m. p.m. Requester: Phone: Approved per applicable codes. Corrections required prior to approval. COMMENTS: bkc $47.00 REINSPECTION FIE REQUIRED. Prior to inspection, fee must be paid at 6300 Southcenter Blvd., Suite 100. Cali to schedule reinspection. Rnrninf Nnr ••••::•'.r.'?;;:V....,i'."`",r''' .. . .'.t ',;i:: • ....:.i'i , ..1. t'A•4 -44 • -F66 ............................................................................ • PRELIMINARY GEOTECHNICAL REPORT Tukwila Parking Lot re • 15400 Block of 65th Avenue South $5$ Tukwila, Washington P•il • Project No T-4110 t; N:4 Terra. Associates, Inc. • ”,••Ads•Ave t .y.g..4•91:2Ag•X., '1 ":1•,:TIA.4P44 ,;•is).= ..i.00,..4,4:4,eVark•t`thlei.14.,P44:•,..1t4:4•4;t:::Wik:AiPD, Prepared for: City of Tukvvila c/o Roth and Hill Engineering Partners, Inc. Bellevue, Washington September 29, 1998 RECEIVED AUG 1 8 1999 eft r•er.6%.4...A.■ r 3 • 7 r 1 1 1 t 1 d 1 TERRA ASSOCIATES, Inc. Consultants in Geotechnical Engineering, Geology and Environmental Earth Sciences September 29, 1998 Project No. T-4110 City of Tukwila c/o Mr. Mark Cole, P.E. Roth and Hill Engineering Partners, Inc. 14450 NE 29th Place, Suite 101 Bellevue, Washington 98007 Subject: Preliminary Geotechnical Report Tukwila Parking Lot 15400 Block of 65th Avenue South Tukwila, Washington Dear Mr. Cole: As requested, we have conducted a preliminary geotechnical engineering study for the subject project. The attached report presents our findings and recommendations for the geotechnical aspects of the anticipated project design and construction. Our field exploration indicates the site is generally underlain by variably thick layers of very dense silty sand and moderately to completely weathered sandstone of the Renton Formation. Excavation depths may be limited by the some of the less weathered rock due to excavation difficulty. In our opinion, the subsurface conditions at the site are suitable for the planned parking lot construction, provided the recommendations presented in this report are incorporated into project design and construction. The competent nature of the on -site native soils and weathered rock indicates the site's slopes are stable and, with proper grading, will not be impacted. by the proposed construction. 1 • 1 1 1 • 1 Mr, Mark Cole, P.E. September 29, 1998 We appreciate the opportunity to be of service during this phase of the project. We trust the information presented in this report is ent for your current needs. If you have any questions or require additional informatio • Sincerely yours, Kevin P. Roberts, P.E. Project Engineer T1feodre J. Schep , P.E. Principal Engine KPR/I'JS:dvp . Figures Vicinity Map Figure 1 Exploration Location Plan Figure 2 Retaining Wall Drainage Detail Figure 3 Appendices Field Exploration and Laboratory Testing Appendix A Environmental Checklist Appendix B F 1 • Preliminary Geotechnical Report Tukwila Parking Lot 15400 Block of 65th Avenue South Tukwila, Washington 1.0 PROJECT DESCRIPTION The project will consist of the construction of a parking lot in the 15400 Block of 65th Avenue South in Tukwila, Washington. The location of the project site is shown on the Vicinity Map, Figure 1. We were provided with two undated conceptual site plans prepared by the City of Tukwila Public Works Department. The site plans show two alternate parking lot layouts (Alternates A and B). Each layout indicates that construction will occur north and adjacent to existing parking areas east of City Hall. Access to the proposed parking areas will be from the existing southern parking locations, and from a new access drive leading westward to the site from 65th Avenue South. Plans indicating proposed grading configurations are not available at this time. The presence of gentle to steep slopes at the site indicates moderate grading will be required to establish parking lot grades. The recommendations contained in this report are based on our current understanding of the project. Once project drawings and specifications are made available, we should review them to verify that these preliminary recommendations have been properly interpreted_ in design, and to provide additional recommendations if required. 2.0 SCOPE OF WORK On August 17, 1998, we excavated 9 backhoe test pits at the site to depths ranging between 5.0 and 10.5 feet below existing surface grades. Using the information obtained from the subsurface exploration, we performed analyses to develop preliminary geotechnical recommendations for project design and construction. Specifically, this report addresses the following: • • • • • • • • • Soil and groundwater conditions Subgrade preparation and grading General site stability Structural fill Cut and fill slopes Excavations Retaining walls Surface and subsurface drainage Pavement sections 1 1 1 1 1 1 1 September 29, 1998 Project No. T-4110 3.0 SITE CONDITIONS 3.1 Surface The subject property is bounded to the west and south by office complexes. A residential property and 65th Avenue South bound the site to the north and east, respectively. The site is primarily undeveloped. A small City parking lot, accessed from adjacent southern parking areas, is located in the central portion of the site. We noted remnants of a small structure's concrete slab and foundations in the northeastern part of the site. Short rockeries are also present in this area, adjacent to a driveway accessing the southeastern corner of the property. The site is situated on an overall east- facing hillside. An approximately 20 -foot high, east - facing slope rises up from 65th Avenue South to relatively flat terrain in the east - central part of the site. This slope shows an overall inclination of 30 percent, with locally steeper parts standing at 80 percent. The site's central portion contains a broad swale with side slopes ranging to a maximum inclination of approximately 40 percent. West of the swale, the ground surface rises gradually to gently sloping areas in western site locations. An approximately 30 -foot high (maximum) south - facing cut slope extends downward from the southwestern site corner to the adjacent City parking lot. All slopes were vegetated with shrubs and/or groundcover and showed no signs of significant erosion or instability. In addition, no zones of emergent groundwater were observed on the slopes. At the time of our visit, we did not observe any standing or flowing water at the site. Vegetation primarily consisted of short grasses in the open areas, shrubs, and a variety of scattered small to mature deciduous and coniferous trees. 3.2 Soils Excavation of the test pits at the site revealed a 6- to 18 -inch thick layer of organic topsoil or surficial fill. All of the test pits showed glacial till or till -like soils to depths ranging from 1.5 feet to 10.0 feet below existing site grades. These soils consisted of very dense, silty fine to medium sand with gravel and gravelly silty sand. The till soils contained variable amounts of cobbles and, as shown by Test Pits TP -3, TP -5, and TP -7 through TP -9, numerous small to large boulders. Test Pits TP -1, TP -5, and TP -7 through TP -9 were terminated within the glacial till. In Test Pits TP -2 through TP-4 and TP -6, the glacial till or till -like soils were underlain by weathered sandstone of the Renton Formation. In Test Pits TP -2 through TP-4, the sandstone was completely weathered to dense silty sand. In Test Pits TP -3, TP-4, and TP -6, we encountered fractured, moderately to highly- weathered sandstone at depths ranging from 1.5 feet to 8.5 feet. These test pits were terminated within the moderately to highly - weathered sandstone due to practical backhoe refusal. No groundwater or caving of the test pit walls was noted during excavation of the test pits. I 1 1 September 29, 1998 Project No. T-4110 The Geologic Map of the Des Moines Quadrangle, Washington, by Howard H. Waldron (1962) shows the site geology mapped as Tertiary intrusive rocks. The variably- weathered sandstone observed at the site correlates better with the Renton Formation (Ter) mapped approximately one -fourth mile north of the site. In addition, the glacial till noted in some of the test pits correlates with the "Ground moraine deposits (Qgt)" mapped one - eighth mile west of the site. The Test Pit Logs in Appendix A present more detailed descriptions of the subsurface conditions encountered. The approximate test pit locations are shown on Figure 2. 4.0 GEOLOGIC HAZARDS 4.1 Erosion The soils encountered on -site are classified as "Urban Land" (Ur) by the Soil Conservation Service (SCS). According to the classification, the erosion hazard of these soil; is "slight to moderate," With the existing slope gradients ranging up to 80 percent, the silty sand soils will have a high potential for erosion when exposed during construction. 4.2 Landslide The site contains slopes that are inclined in excess of 40 percent, as well as slopes ranging from 20 to 40 percent that are underlain by relatively impermeable soils or bedrock. These areas are classified under City of Tukwila Municipal Code as "Class 3 Landslide Hazard" areas. We contacted Tukwila Public Works to inquire if any records exist of past soil instability on or adjacent to the site. A City representative indicated he was not aware of documented soil instability in the site's vicinity. During our site visit, we did not observe any surface features indicating past or current slope stability problems. Based on these observations and information, the site geology, and site topography, it is our opinion that the site is not a landslide hazard area. 5.0 DISCUSSION AND RECOMMENDATIONS 5.1 General Our subsurface exploration indicates that competent, glacially- derived soils and weathered rock underlie the site. Accordingly, pavement sections constructed on the site may be supported on the silty sand or weathered rock, or on structural fill placed on these soils. September 29, 1998 Project No. T-4110 At a depth of five feet, Test Pit TP -6 encountered hard, moderately- weathered sandstone that was very difficult to excavate with a backhoe. Based on this, cut and fill depths for the project may be limited in some locations. The contractor should expect some difficulty excavating the moderately- weathered material during grading operations. Based on our field observations, we do not expect unusual difficulty in excavating the overlying completely to highly weathered sandstone. However, because of its fines content and potential for large clasts, special attention will be required during placement and compaction of this material as structural fill. If difficulties are encountered during compaction of the weathered rock material, it may be more desirable to import soil to the site for use as structural fill. The following sections provide preliminary recommendations regarding the above issues and other geotechnical . design considerations. These recommendations should be incorporated into the final design drawings and construction specifications. t 1 1 1 t 1 i 1 1 1 5.2 Subgrade Preparation and Grading To prepare the site for construction, all vegetation, organic surface soils, and other unsuitable materials should be stripped and removed from the areas under construction. Surface stripping depths of 6 to 18 inches should be expected to remove organic topsoil and existing surficial fill. Organic topsoil will not be suitable for use as structural fill but may be used for limited depths in non - structural areas or for landscaping purposes. Once clearing and grubbing operations are complete, cut and 'fill operations to, establish desired grades can be initiated. We recommend placing pavement sections on undisturbed surfaces of the native medium dense to very dense silty sand, moderately to completely - weathered sandstone, or suitably compacted structural fill placed on these materials. Prior to placing fill, we recommend proofrolling all exposed surfaces to determine if any isolated soft and yielding areas are present. Proofrolling should also be performed in cut areas that will provide direct support for new construction. A representative of Terra Associates, Inc., should observe all proofrolling operations. We also recommend field evaluations at the time of construction to verify stable subgrades. If excessively yielding areas are observed, they should be cut to a firm subgrade and filled to grade with structural fill. In pavement areas, if the depth of excavation to remove unstable soils is excessive, use of geotextile fabric, such as Mirafi 500X or equivalent, in conjunction with structural fill can be considered in order to limit the depth of removal. In general, a minimum of 18 inches of clean, granular structural fill over the geotextile fabric should establish a stable bearing surface. Review of the conceptual site plan indicates fill placement may occur on sloping subgrades. Where fill is placed on subgrades inclined at greater than 25 percent, we recommend benching and keying fill slopes into competent native soils as shown on Figure 3. Abundant small to large boulders were observed during excavation of several of the test pits. During.grading, the contractor should be prepared to remove them from site soils prior to reuse as structural fill. D...... AT.. A 1 4 } 1 1 1 r a 1 September 29, 1998 Project No. T-4110 Extreme care should be taken to ensure that exposed surfaces of the silty sand and weathered rock do not become disturbed due to weather and construction traffic. It may be necessary to protect pavement area subgrades with a layer of crushed rock to guard against soil degradation. Laboratory sieve results indicate most of the on -site soils and weathered rock contain a relatively high fraction of fines (silt and clay particles), which will make them particularly sensitive to moisture conditions. The ability to use these materials from site excavations as structural fill will depend on their moisture content and the prevailing weather conditions at the time of construction. Our field and laboratory results also show that the near - surface till soils at the site are near their optimum moisture content. The results also show that the moisture contents increase with depth in the till soils and completely weathered sandstone. Reuse of these deeper materials will likely entail scarification and drying prior to compaction. We anticipate the weathered and fractured sandstone at the site can be reused as structural fill. This material contains variable amounts of silt as well as minerals that typically weather to clay. The presence of silt and clay _ will influence its compactibility from the standpoint of sensitivity to moisture. Moreover, excavation of the sandstone will likely produce large clasts of intact material that will need to be broken to smaller sizes to facilitate placement and compaction as fill. To facilitate proper compaction of these soils, consideration should be given to using a sheep's -foot roller. The feet will break up larger clasts and cause mixing of the clasts and clay, thereby improving the homogeneity of the material and; thereby, its compaction. If grading activities must take place during wet weather or on a wet subgrade, the owner should be prepared to use wet weather structural fill. For this purpose, we recommend using a granular soil that meets the following grading requirements: U.S. Sieve Size Percent Passing 3 inches 100 No. 4 75 maximum No. 200 5 maximum* *Based on the 3/4 -inch fraction. Prior to use, Terra Associates, Inc., should examine and test all on -site or imported materials proposed for use as structural fill. Structural fill should be placed and compacted in accordance with City of Tukwila standards. At minimum, we recommend that structural fill be placed in uniform loose layers not exceeding 12 inches and compacted to a minimum of 95 percent of the soil's maximum dry density, as determined by ASTM Test Designation D -698 (Standard Proctor). The moisture content of the soil at the time of compaction should be within two percent of its optimum, as determined by this standard. In non - structural areas or for backfill in utility trenches below a depth of 4 feet, the degree of compaction can be reduced to 90 percent. 4. 5.3 Cut and Fill Slopes September 29, 1998 Project No. T-4110 All permanent cut and fill slopes should be graded with a finish inclination of no greater than 2:1 (Horizontal:Vertical). All fill placed for embankment construction should meet the requirements for structural fill as described in the Site Preparation and Grading section of this report. Structural fill slopes graded to finish 1 inclinations steeper than 2:1 may be considered. However, it will be necessary to design and construct these slopes using geogrid/geotextile reinforcement. We can provide design and construction recommendations for steeper fill slope sections, if desired. Once cleared of vegetative cover, the soils will be susceptible to surficial instability and erosion from concentrated surface water runoff if they are not suitably protected. During construction, soils exposed on excavated slopes should be covered with straw or securely- anchored plastic sheeting. Upon completion of grading, slope faces should be appropriately vegetated or provided with other physical means to guard against erosion. 5.4 Excavations T All excavations at the site associated with utility construction must be completed in accordance with local, state, or federal requirements. Based on current Occupational Safety Health Administration (OSHA) regulations, the dense weathered sandstone and very dense till soils at the site would be classified as Group A. For temporary in excavations more than 4 feet in these materials, the side slopes should be completed with a gradient of .75 :1 or j flatter. If there is insufficient room to complete the excavations in this manner, you may need to consider using temporary shoring to support the excavations. The above information is provided solely for the benefit of the owner and other design consultants, and should not be construed to imply that Terra Associates, Inc., assumes responsibility for job site safety. It is understood that job site safety is the sole responsibility of the project contractor. 5.5 Retaining Walls The earth pressures that develop on cantilevered (unrestrained) or restrained retaining walls will partly depend on the quality of the wall backfill. We recommend placing and compacting wall backfill as structural fill. Below pavements, the backfill should be compacted to a minimum of 95 percent of its maximum dry unit weight, as determined by ASTM Test Designation D -698 (Standard Proctor). In unimproved areas, the relative compaction may be reduced to 90 percent. To prevent development of hydrostatic pressure, wall drainage must also be installed. A typical recommended wall drainage detail is shown on Figure 4. j • With wall backfill properly placed and compacted and drainage installed, unrestrained walls should be designed for an active earth pressure imposed by an equivalent fluid weight of 35 pounds per cubic foot (pcf) for horizontal backfill and 50 pcf where the backfill is sloped to 2:1. At -rest earth pressures equivalent to fluids weighing 50 pcf sfor horizontal backfill and 65 pcf for a 2:1 backslope may be used for restrained walls. Walls subject to traffic surcharge should be designed for an additional wall height to two feet. �Y• September 29, 1998 Project No. T-4110 The active earth pressure values given above assume that no other surcharge loads will act on the wall. If such conditions exist, then the imposed loads must be included in the wall design. During construction, compaction of backfill with a heavy roller that is too close to the wall could result in excessive wall pressures and damage to the wall. To reduce the risk of damage to the wall due to compaction, backfill placed within five feet from the wall a should be compacted with hand - operated equipment. 1 1. 1 1 J 5.6 Drainage Final exterior grades should promote free and positive drainage away from site slopes at all times. To minimize the potential for slope instability, it is essential that concentrated stormwater runoff be routed away from slopes or properly tightlined to approved discharge points at the slope's toe. The conceptual site plan shows a buried stormwater detention vault located at the southern terminus of 64th Avenue South near the northern property line. We recommend routing stormwater from the vault to a suitable discharge point. 5.7 Utilities Utility pipes should be bedded and backfilled in accordance with American Public Works Association (APWA) or City of Tukwila specifications. As a minimum, trench backfill, should be placed and compacted as structural fill as described in the Subgrade Preparation and Grading section of this report. 5.8 Slope Stability In general, the sloping soils and weathered rock at the site are stable with respect to static and seismic loading. This is due to the overall modest grades exhibited by the site's slopes, the relatively competent nature of the soils, and the lack of groundwater. Based on our understanding of planned grading concepts, it is our opinion that there will be no adverse impact to the current stability of the site slopes or those on adjacent properties. However, we should review the final grading plan when it is available to complete a more detailed evaluation of the stability of the site's soils in relation to placement of fill and other geotechnical considerations. 5.9 Pavements Traffic loads on parking lot pavements will be relatively light, consisting primarily of those imposed by passenger cars. Pavements should be constructed on subgrades prepared as described in the Subgrade Preparation and Grading section of this report. Regardless of the degree of relative compaction achieved, the subgrade must be firm and relatively unyielding before paving. Proofrolling the subgrade with heavy construction equipment should be completed to verify this condition. September 29, 1998 Project No. T -4110 With a stable subgrade prepared as recommended, we recommend the following pavement sections: • Two inches of asphalt concrete (AC) over four inches of crushed rock base (CRB) 7 • Two inches of AC over three inches of asphalt treated base (ATB) The paving materials used should conform to the Washington State Department of Transportation (WSDOT) specifications for Class B asphalt concrete, ATB, and CRB. 5.10 Environmental Checklist We understand completion of a SEPA checklist is required for the project. Appendix B contains the completed portion of the checklist entitled "B. Environmental Elements, 1. Earth." 6.0 ADDITIONAL SERVICES Terra Associates, Inc., should review the final design and specifications .in order to verify that earthwork and foundation recommendations have been properly interpreted and incorporated into the project design and construction. We should also provide geotechnical services during construction in order to observe compliance with the design concepts, specifications, and recommendations. This will also allow for design changes if subsurface conditions differ from those anticipated prior to the start of construction. 7.0 LIMITATIONS We prepared this report in accordance with generally . accepted geotechnical engineering practices. This report is the property of Terra Associates, Inc., and is intended for specific application to the Tukwila Parking Lot project. This report is for the exclusive use of City of Tukwila, Roth and Hill Engineering Partners, Inc., and their authorized representatives. 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VICINITY MAP TUKWILA PARKING LOT TUKWILA, WASHINGTON TERRA ASSOCIATES to s� Geotechnical Consultants Proi- No.4110 1 Date SEPT. 199R 1 Finiirp 1 w 0 0 ! 7_ -- 1 1 - l #13; kill /2-.,;. 1 Y �{�- / 1 -- /II1111111I' \�t',A, \I- - `- / I 'I- +ll I11I IIIIII'0•�, N �� . / •I'._ �11/►I I III 't; + - %; 1 `'�,..'"42''...i.:.'1//1 1 IIII 3;.: :�r_— --- f2 1I1 �'`��_'-- ,-- - - - - -' .I — i 1 \ . --,r.., ) :J ' ' ' ��1' ' \ ) \ •. , -,,— v. m Pi g m �Tr N o in z rn z -a N6' r I Q7 a C7 O z s. I \s\\ \ 0 \\ c �r— o . \ •, \ 1I \611 , , li , i , \I(! 1 ,A' I \ \ r��� \...... ='q� �,% �- l�� __\\ \I \\:./,'‘‘. \\ ,' //� �, \111 I / / / /I/ ,ti CZ , ,i i�I t . 1' /,-)///,:///./... \ \ O� 1 / ..i / 1 1.,/, ' :\ ) /1 / I �1 1 ;-i' 1 I/ / / . O :I; l/ � ll _ L� =a' `�s'2xr�9 • I I ss iP c r, ... . .._ ......__ ----- _ . ,..... ,.....„. ...... ___ ''. 1,777;Z - /,S''( sit'',`` i o / F 1 t SLOPE TO DRAIN NEW •STRUCTURAL FILL `\` .411141111h'ilibt MAXIMUM SLOPE GRADIENT:, 2:1(H:V) 2 EXISTING ��'� �' GRADE �,,���� � ... ... .:.t'•`:•'••• ., , . _�� TYPICAL .11.1...7.-.7. ►��►��� �, :.i MAY RE( �._ CONDITIONS ARE INDICATED GRADE AFTER THE REMOVAL OF ;, ;; ;; ::.:; •- TOPSOIL AND OTHER LOOSE SOILS KEY CUT AND TOE DRAIN — 4" DIAMETER PERFORATED PIPE ENVELOPED IN 1 cu. ft.. 3/4" DRAINAGE 'GRAVEL NOT TO SCALE NOTES: 1. SLOPE SHOULD BE STRIPPED OF TOPSOIL AND UNSUITABLE SOILS PRIOR TO PLACING ANY FILL. 2. "BENCHES" SHOULD BE A MINIMUM OF 8 FEET WIDE. 3. "KEY" SHOULD BE MINIMUM 2 FEET DEEP AND 10 FEET WIDE, EXTENDING THE FULL LENGTH OF THE SLOPE FACE. 4. FINAL SLOPE FACE SHOULD BE DENSIFIED BY COMPACTION. 5. PLANT OR HYDROSEED SLOPE FACE TO REDUCE EROSION POTENTIAL. 6. ALL STRUCTURAL FILL SHOULD BE COMPACTED TO 95% OF SOILS MAXIMUM DRY DENSITY PER ASTM D -698 (STANDARD PROCTOR). TERRA ASSOCIATES ' "otechnicai Consultants GENERAL SLOPE FILL DETAIL TUKWILA PARKING LOT TUKWILA, WASHINGTON Proj.No, 4110 1 Date SEPT. 19981 Figure 3 J 1 12" MINIMUM WIDE FREE — DRAINING GRAVEL SLOPE TO DRAIN 4" DIAMETER PVC PERFORATED PIPE EXCAVATED SLOPE (SEE REPORT FOR APPROPRIATE INCLINATIONS) COMPACTED STRUCTURAL BACKFILL 12" OVER THE PIPE 3" BELOW THE PIPE NOT TO SCALE TERRA • • ASSOCIATES " / 'Geotechnical Consultants RETAINING WALL DRAINAGE DETAIL TUKWILA PARKING LOT TUKWILA, WASHINGTON Proi. No. 4110 1 Date SEPT. 1998 1 Faure 4 L APPENDIX A FIELD EXPLORATION AND LABORATORY TESTING Tukwila Parking Lot Tukwila, Washington On August 17, 1998, we performed our field exploration at the site by excavating 9 test pits to depths ranging from 5.0 to 10.5 feet below existing grades. The test pits were excavated with a rubber -tired backhoe. The test pit locations are shown on Figure 2. The test pit locations were approximately determined by pacing relative to site boundaries, features, and adjacent test pits. Test pit elevations were 'interpreted from the provided conceptual site plan. The Test Pit Logs are presented on Figures A -2 through A -6. An engineer from our office maintained a log of each test pit as it was excavated, classified the soil conditions encountered, and obtained representative soil samples. All soil samples were visually classified in accordance with the ,Unified Soil Classification System shown on Figure A -1. Representative soil. samples obtained from the test pits were placed in sealed plastic bags and taken to our laboratory for further examination and testing. The moisture content of each sample was measured and is reported on the Test Pit Logs. Grain size analyses were performed on three of the samples, the results of which are presented on Figures A -7 and A -8. 1 1 1 t t 1 t ( MAJOR DIVISIONS LETTER SYMBOL TYPICAL DESCRIPTION cn 'di J m O co N U) V id o m LLI Z .ce Z E o :CZ CD N o co a Z c c < cc O o "J U g GRAVELS More than 50% of coarse fraction is larger than No. 4 sieve Clean Gravels ( less than 5% fines) GW Well- graded gravels, gravel -sand mixtures, little or no fines. GP Poorly- graded gravels, gravel -sand mixtures, little or no fines. Gravels with fines G M Silty gravels, gravel- sand -silt mixtures, non plastic fines. GC .Clayey gravels, gravel- sand -clay mixtures, plastic fines. SANDS More than 50% of coarse fraction Is smaller than No. 4 sieve Clean Sands (less than 5% 5 fines) SW Well- graded sands, gravelly sands, little or no fines. S P Poorly- graded sands or gravelly sands, little or no fines. Sands with fines SM Silty sands, sand -silt mixtures, non - plastic fines. SC Clayey sands, sand -clay mixtures, plastic fines. FINE GRAINED SOILS More than 50% material smaller than No. 200 sieve size SILTS AND CLAYS Liquid limit is less than 50% ML Inorganic silts, rock flour, clayey silts with slight plasticity. CL Inorganic clays of low to medium plasticity, (lean clay). OL Organic silts and organic clays of low plasticity. SILTS AND Liquid limit is greater CLAYS MH Inorganic silts, elastic. than 50% CH Inorganic clays of high plasticity, fat clays. OH Organic clays of high plasticity. HIGHLY ORGANIC SOILS PT Peat, DEFINITION OF TERMS AND SYMBOLS . SAND or GRAVEL Standard Penetration Density - Resistance In Blows /Foot 2" OUTSIDE DIAMETER SPLIT 1 SPOON SAMPLER 2.4" INSIDE DIAMETER RING SAMPLER IL OR SHELBY TUBE SAMPLER 1 WATER LEVEL (DATE) Tr TORVANE READINGS, tsf Pp PENETROMETER READING, tsf DD DRY DENSITY, pounds per cubic foot LL LIQUID LIMIT, percent PI PLASTIC INDEX - N STANDARD PENETRATION, blows per foot Very loose 0 -4 Loose 4 -10 Medium dense 10 -30 Dense 30 -50 Very dense >50 SILT or CLAY Standard Penetration Consistency Resistance in Blows /Foot Very soft 0 -2 Soft 2 -4 Medium stiff 4 -8 Stiff 8-16 Very stiff 16 -32 Hard >32 TERRA ASSOCIATES Geotechnical Consultants UNIFIED SOIL CLASSIFICATION SYSTEM TUKWILA PARKING LOT TUKWILA, WASHINGTON \ \` ``•..�� Logged by: KPR Date: 8/17/98 Depth (ft.) 0 5— Test Pit No. TP -1 Approximate Elev. 127' Soil Description (8 inches Topsoil) Light brown gravelly silty SAND with occasional cobbles, rare boulder, clasts of sandstone, abundant roots to 2 feet, dense becoming very dense, damp. Glacial Till. (SM) Moisture Content ( %) 7.3 8.7 8.6 10- _ Test pit terminated at 8.5 feet due to very difficult digging. No groundwater or caving observed. 15 Test Pit No, TP -2 Logged by: KPR Date: 8/17/98 Depth (ft.) Soil Description 0 Topsoil; brown organic silty very fine sand with abundant roots, damp. (OUSM) Approximate Elev. 121' 5— 10 15 Moisture Content ( %) Brown silty fine SAND with gravel, dense, damp. Glacial Till. (SM) Yellow -tan mottled silty medium SAND, micaceous, dense, moist. Renton Formation. (SM; completely weathered sandstone) Increasingly difficult digging. 10.4 8.3 17.8 Test pit terminated at 10.5 feet, No groundwater or caving observed. TERRA ASSOCIATES Geotechnlcal Consultants TEST PIT LOGS TUKWILA PARKING LOT TUKWILA, WASHINGTON Prni Nn T -4111) l rata FPT 1448 1 Finure A -2 Logged by: KPR Date: 8/17/98 Depth (ft.) 0 5 10 15 Test Pit No. TP -3 Soil Description Approximate Elev. 119' Moisture Content ( %) Topsoil; with roots. Brown silty fine SAND with gravel, dense, damp, with numerous boulders. Glacial Till. (SM) Yellow -tan mottled silty medium SAND, micaceous, dense, moist. Renton Formation. (SM; completely weathered sandstone) Yellow -tan with orange oxidation, medium - grained SANDSTONE, highly weathered, soft, moist. Renton Formation. 10.6 21.2 12.5 Test pit terminated at 10.5 feet due to difficult digging. No groundwater or caving observed. Logged by: KPR Date: 8/17/98 Depth (ft.) 0 5 10 15 Test Pit No, TP -4 Soil Description Approximate Elev. 108' Moisture Content ( %) Topsoil. Light brown silty very tine SAND with some gravel, roots, medium dense, damp. Glacial Till. (SM1 Yellow -tan to brown with orange oxidation silty medium SAND, dense, moist. Renton Formation. (SM; completely weathered sandstone) Yellow -tan with orange oxidation, medium- grained SANDSTONE, highly weathered. soft. moist. Renton Formation. 8.3 43.7 10.2 Test pit terminated at 10.5 feet due to difficult digging. No groundwater or caving observed. TERRA ASSOCIATES Geotechnical Consultants TEST PIT LOGS TUKWILA PARKING LOT TUKWILA, WASHINGTON Prni Jr, T.41111 1 flats CFPT 1 QQA 1 Figure A -3 Logged by: KPR Date: 8/17/98 Depth (ft.) 0 5 10 15 Test Pit No TP -5 Soli Description Approximate Elev. 111' Moisture Content ( %) FILL; brown -gray organic silty fine sand with gravel, loose, damp. (OL/SM) Tan to brown silty fine to medium SAND with gravel, cobbles, and numerous 12 -inch to 24 -inch boulders, very dense, moist. Till -like. (SM) 17.1 9.7 Test pit terminated at 6 feet on large boulder. No groundwater or caving observed. Logged by: KPR Date: 8/17/98 Depth (ft.) 0 5 10 15 Test Pit No. TP -6 Soil Description Approximate Elev. 105' Moisture Content ( %) (9 inches Topsoil) Brown silty very fine SAND with sandstone clasts, medium dense, damp. (SM) Brown, fractured medium- grained SANDSTONE, sandy silt in matrix, gravel to boulder -sized clasts, highly weathered, damp. Renton Formation. Becomes moderately weathered, hard, and fewer fractures. 8.0 7.9 Test pit terminated at 5 feet due to backhoe refusal. No groundwater or caving observed. TERRA ASSOCIATES Geotechnical Consultants TEST PIT LOGS TUKWILA PARKING LOT TUKWILA, WASHINGTON Proi. No. T -4110 1 Date SEPT. 19981 Fiaure A -4 r • i 1 I T i Logged by: KPR Date: 8/17/98 Depth (ft.) 5 10 15 Test Pit No. TP -7 Soil Description Approximate Elev. 100' Moisture Content ( %) Logged by: KPR Date: 8/17/98 Depth (ft.) 0 5 10 15 Test Pit No. TP -8 Soil Description Approximate Elev. 94' Moisture Content ( %) Topsoil. _ Light brown silty very fine SAND with some gravel, cobbles and 7.6 _ numerous 12 -inch to 30 -inch boulders, very large boulder in back 12.2 _ of test pit, very dense, moist. Glacial Till. (SM) 17.1 — Becomes brown, moist and fine to medium - grained at 5 feet. 25.8 No groundwater seepage or caving observed. - Difficult digging. - 23.6 _ Test pit terminated at 10 feet. _ No groundwater or caving observed. Logged by: KPR Date: 8/17/98 Depth (ft.) 0 5 10 15 Test Pit No. TP -8 Soil Description Approximate Elev. 94' Moisture Content ( %) TERRA ASSOCIATES Geotechnlcal Consultants TEST PIT LOGS TUKWILA PARKING LOT TUKWILA, WASHINGTON Prni tin T.411111 nntc QDDT i�� cion 1 FinnrP A -5 (6 inches Topsoil) - 8.9 _ Light brown to brown silty fine to medium SAND with gravel, cobbles, and 12 -inch to 30 -Inch boulders, 4 to 5 -foot boulder in back of test pit, very dense, damp to moist. Glacial Till. (SM) 12.2 _ 17.1 Test pit terminated at 10 feet. _ No groundwater seepage or caving observed. TERRA ASSOCIATES Geotechnlcal Consultants TEST PIT LOGS TUKWILA PARKING LOT TUKWILA, WASHINGTON Prni tin T.411111 nntc QDDT i�� cion 1 FinnrP A -5 t • Logged by: KPR Date: 8/17/98 Depth (ft.) 5 10 15 (_ Test Pit No. TP -9 Soil Description Approximate Elev. 84' Moisture Content ( %) _ - 13 inches Topsoil. Light brown silty fine SAND with some gravel, sandstone clasts, cobbles, - and occasional boulders, very dense, moist. Glacial Till. (SM) 8.2 — Becomes brown and fine to medium - grained at 5 feet. 11.0 - 11.8 _ Test pit terminated at 10 feet. No groundwater or caving observed. TERRA ASSOCIATES Geotechnlcal Consultants TEST PIT LOGS TUKWILA PARKING LOT TUKWILA, WASHINGTON I4 I A 11 _a_ f1 f••• MT . "w'a I A C 1 1 1 1 1 1 1 (1) LtJ >- GRAIN SIZE IN MM C/) C) uJ uJ >— SIZE OF OPENING IN INCHES .001 .002 .003 .004 .006 .008 .01 .02 .03 .04 .06 200 100 60 40 PERCENT COARSER BY WEIGHT 0 (C) 00 - .001 20 10 4 1/4 3/8 1/2 5/8 3/4 1 2 3 4 6 12 r- CD 0 oz 0 0 PERCENT FINER BY WEIGHT 0 .002 .003 .004 .006 .008 .01 .02 .03 .04 .06 .08 .1 (.1) LLJ 2 in .3 .4 .6 8 L.LJ (7) 6 8 10 20 30 40 60 80 100 200 300 0 AM./II/WM.6 CL -J gravelly silty SAND (/) ..-• CL 41■■ C=? 0 CV CO 0.1 • 0 TERRA ASSOCIATES Geotechnical Consultants GRAIN SIZE ANALYSIS TUKWILA PARKING LOT TUKWILA, WASHINGTON Proj. No.4110 I Date SEPT. 1998 I Figure A-7 1 j t 1 1 1 t s 1 1 GRAIN SIZE IN MM C/) (1) Z W w N NUMBER OF MESH PER INCH. U.S. STANDARD SIZE OF OPENING IN INCHES .001 °- .002 .003 .004 .006 .008 .01 .02 .03 .04 .06 200 100 60 40 20 10 4 1/4 3/8 1/2 3/4 1 2 3 4 6 12 O PERCENT COARSER BY WEIGHT O O O O O t0 O n O CO O Q7 O O Co O O O CO O n O (O O O PERCENT FINER BY WEIGHT O N O .001 .002 .003 .004 .006 .008 .01 .02 .03 .04 .06 .08 .1(/') W 2� .3 E 4 .6 Z 8w 1 N 2 Z Q 3 C..) 4 6 8 10 20 30 40 60 80 100 200 300 O w w (f) N 0 w z N Q] Co U J 0— J J 0 a 0 N m w 0o TERRA ASSOCIATES Geotechnical Consultants GRAIN SIZE ANALYSIS TUKWILA PARKING LOT TUKWILA, WASHINGTON Proj. No.4110 I Date SEPT. 1998' Figure A -8 APPENDIX B ENVIRONMENTAL CHECKLIST Tukwila Parking Lot Tukwila, Washington a 4 TO BE COMPLETED BY APPLICA( ( Evaluation for ' Agency Use Only 1 1 B. ENVIRONMENTAL ELEMENTS 1. Earth a. General description of the site (circle one): Flat, rolling, hilly, steep slopes, mountainous, other steep slopes b. What is the steepest slope on the site (approximate percent slope)? 80 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. silty sand (Ur) d. Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe. no e. Describe the purpose, type, and approximate quanti- ties of any filling or grading proposed. Indicate source of fill. Grades may be raised in portions of the site for parking lot construction. _ f. Could erosion .occur as a result of clearing, construction, or use? If so, generally describe. Yes. High erosion potential exists for exposed silty sands if not suitably prntnr•tar'i g. About what percent of the site will be covered with impervious surfaces after project construction (for example, asphalt or buildings)? _A_ 1 1 f } 1 1 r h. Proposed measures to reduce or control erosion, or other impacts to the earth, if any: Straw or securely- anchored plastic sheeting. 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. b. Are there any off -site sources of emissions or odor that may affect your proposal? If so, generally describe. c. Proposed measures to reduce or control emissions or other impacts to air, if any: 3. Water a. Surface: '1) Is there any surface water body on or in the immediate vicinity of the site (including year - round and seasonal streams, saltwater, lakes, ponds, wetlands)? If yes, describe type and provide names. If appropriate, state what stream or river it flows into. Evaluation for Agency Use Only 1 J 1 1 i t a 1 3 1 s City ofrukwila City Hall Parking Lot Expansion Storm Water Report Prepared by Roth Hill Engineering Partners - TUKWILA 3 1 3 1 1 1 C. Project Overview This report addresses the drainage requirements required to construct a 90 stall parking lot north of Tukwila City Hall Building. The stormwater calculations and proposed water quality standards are based on the King County Surface Water Design Manual September 1998. Existing Site Conditions The site is located west of 65th Ave S. The existing drainage pattern are sloping towards the existing swale located in the central portion of the site. The drainage is collected by the swale and then channeled through a catchbasin located at 6300 Southcenter Blvd. The infiltration trench located at the northwestern end is failing and would require diverting the flow to the public stormwater system. On Site Total Area = 3.18 Acres Impervious Area = 0.27 Acres Till Pasture — 2.91 Acres Proposed Site Conditions The proposed parking lot can be subdivided into three sections namely: King County Housing Authority (KCHA), Xerox Building, and City of Tukwila Parking Lot. The parking lot will be paved and would be considered impervious. The drainage system from the proposed parking lot will connected to the public stormwater system located at 65th Avenue S. There will be sufficient grade drop to convey the stormwater flow from the parking lot without having to be concerned about backing up. Total Area = 3.18 Acres Impervious Areas= 1.27 Acres Till Pasture = 1.91Acres Regional Scale Factors 1.0 Seatac KCRTS Soil Group Till KCRTS Cover Group Pasture Stormwater Design The stormwater from this site is planned to be discharged in to Green River, the requirements would be conveyance protection under the 1998 King County regulations.. Level 2 .The requirements would require detention matching 2 year and 10 year storm requirements. The King County Run Time Series (KCRTS) program was used to determine the size of the detention pond both for water quality and detention. Design Storm Predeveloped Discharge 10 year 0.25 cfs 2 year 0.15 cfs Surface Coverage Conditions Information The proposed parking lots will increase impervious surface contributing flow to the downstream system. The area west of the proposed City Hall Parking Lot will flow down the slope and into the catch basin for the existing City Hall Lot. The east slope adjacent to 65th Avenue S will flow down the slope and will be captured by the storm systems along 65th Avenue S. The area north from the failed infiltration basin will be bypassed into the catch basins along 65'h Avenue S. F.] 7 1 1 a 1 KCRTS Program...File C: \KCRTS\ [C] ST 0.00 2.91 0.00 O .00 0.00 0.00 0.00 O .27 predev.tsf T 1.00000 T [C] ST 0.00 2.91 0.00 0.00 0.00 0.00 O .00 0.27 predev.tsf T 1.00000 T [T] [P] predev.tsf predev.pks [R] [C] ST 0.00 1.91 0.00 0.00 0.00 0.00 0.00 1.27 dev.tsf T 1.00000 Record Directory: CREATE a 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 new Time Series 0.000000 O .000000 0.000000 O .000000 0.000000 0.000000 O .000000 0.000000 Till Forest Till Pasture Till Grass Outwash Forest Outwash Pasture Outwash Grass Wetland Impervious CREATE a new Time Series 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 O .000000 0.000000 O .000000 0.000000 O .000000 O .000000 O .000000 O .000000 Till Forest Till Pasture Till Grass Outwash Forest Outwash Pasture Outwash Grass Wetland Impervious Enter the Analysis TOOLS Module Compute PEAKS and Flow Frequencies RETURN to Previous Menu CREATE a new Time Series 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 O .000000 0.000000 O .000000 O .000000 0.000000 0.000000 O .000000 0.000000 Dn rYC 1 Till Forest Till Pasture Till Grass Outwash Forest Outwash Pasture Outwash Grass Wetland Impervious Record T [T] Enter the Analysis TOOLS Module [R] RETURN to Previous Menu [F] Size a Retention /Detention FACILITY Automatic Design convey.rdf 5 Route Time Series T rdout.tsf F 0.000000 (filename) (filename) (filename) T T F F 10/ 1/ 0 0:00 10/30/ 0 23:00 1 Iterate Primary Hydrograph T 7 Enter Tools Module [D] Compute Flow DURATION and Exceedence CANCEL [R] RETURN to Previous Menu 5 Route Time Series T rdout.tsf F 0.000000 (filename) (filename) (filename) T T F F 10/ 1/ 0 0:00 10/30/ 0 23:00 0 Return to Main Menu [X] eXit KCRTS Program Paarg■. 7 Retention /Detention Facility Type of Facility: Detention Pond Side Slope: 2.00 H:1V :1 Pond Bottom Length: 49.51 ft Pond Bottom Width: 24.75 ft Pond Bottom Area: 1226. sq. ft Top Area at 1 ft. FB: 3111. sq. ft 0.071 acres Effective Storage Depth: 4.00 ft Stage 0 Elevation: 100.00 ft ' ..1 0.173 Storage Volume: 7535. cu. ft 0.173 ac -ft Riser Head: 4.00 ft Riser Diameter: 18.00 inches 1 Number of orifices: 2 Full Head Orifice # Height Diameter Discharge I 1 0.00 (ft) (in) (CFS) 1.92 0.200 2 3.00 1.36 0.050 Top Notch Weir: None 1 1 j 1 1 a 1 Stage Elevation Storage Discharge Percolation (ft) (ft) (cu ft) (ac -ft) (cfs) (cfs) 0.00 100.00 0. 0.000 0.000 0.00 0.10 100.10 124. 0.003 0.032 0.00 0.50 100.50 650. 0.015 0.071 0.00 0.90 100.90 1226. 0.028 0.095 0.00 1.30 101.30 1853. 0.043 0.114 0.00 1.70 101.70 2532. 0.058 0.130 0.00 2.10 102.10 3266. 0.075 0.145 0.00 2.50 102.50 4055. 0.093 0.158 0.00 2.90 102.90 4901. 0.113 0.170 0.00 3.00 103.00 5121. 0.118 0.173 0.00 3.40 103.40 6041. 0.139 0.216 0.00 3.80 103.80 7021. 0.161 0.240 0.00 4.00 104.00 7535. 0.173 0.250 0.00 4.10 104.10 7797. 0.179 0.717 0.00 4.20 104.20 8064. 0.185 1.570 0.00 4.30 104.30 8334. 0.191 2.660 0.00 4.40 104.40 8609. 0.198 3.960 0.00 4.50 104.50 8887. 0.204 5'.440 0.00 4.60 104.60 9170. 0.211 6.870 0.00 4.70 104.70 9456. 0.217 7.400 0.00 4.80 104.80 9747. 0.224 7.900 0.00 4.90 104.90 10042. 0.231 8.360 0.00 5.00 105.00 10341. 0.237 8.800 0.00 5.10 105.10 10644. 0.244 9.220 0.00 5.20 105.20 10952. 0.251 9.620 0.00 5.30 105.30 11263. 0.259 10.010 0.00 5.40 105.40 11579. 0.266 10.380 0.00 5.50 105.50 11899. 0.273 10.740 0.00 5.60 105.60 12223. 0.281 11.080 0.00 J 5.70 105.70 5.80 105.80 Routing Hydrographs Hyd Inflow Outflow Target Calc. 1 0.83 2 0.48 3 0.44 4 0.42 5 0.41 6 0.39 7 0.32 8 0.32 0.76 0.21 0.25 0.25 0.32 0.15 0.13 0.12 12552. 0.288 11.420 12885. 0.296 11.740 Peak Stage 4.10 3.39 4.00 3.99 4.02 2.21 1.64 1.37 Route Time Series through Facility Inflow Time Series File:dev.tsf Outflow Time Series File:rdout.tsf Elev 104.10 103.39 104.00 103.99 104.02 102.21 101.64 101.37 Inflow /Outflow Analysis Peak Inflow Discharge: 0.831 CFS at Peak Outflow Discharge: 0.759 CFS at Peak Reservoir Stage: 4.10 Ft Peak Reservoir Elev: 104.10 Ft Peak Reservoir Storage: 7810. Cu -Ft 0.179 Ac -Ft Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea -Tac - -- Annual Flow Rate (CFS) 0.323 0.128 0.215 0.117 0.154 0.250 0.249 0.759 Computed Peak Flow Rates-- - Rank Time of Peak 2 7 5 8 6 3 4 1 Peaks 2/ 9/ 1/ 5/ 3/ 6/ 8/23/ 1/ 5/ 1/18/ 11/24/ 1/ 9/ 1 16:00 2 18:00 3 20:00 4 21:00 5 10:00 6 21:00 6 7:00 8 8:00 Storage (Cu -Ft) 7810. 6017. 7535. 7509. 7576. 3492. 2439. 1964. 0.00 0.00 (Ac -Ft) 0.179 0.138 0.173 0.172 0.174 0.080 0.056 0.045 6:00 on Jan 9 in Year 8 8:00 on Jan 9 in Year 8 Flow Frequency Analysis - Peaks - - Rank Return Prob (CFS) (ft) Period 0.759 4.10 1 100.00 0.323 4.02 2 25.00 0.250 4.00 3 10.00 0.249 3.99 4 5.00 0.215 3.39 5 3.00 0.154 2.39 6 2.00 0.128 1.64 7 1.30 0.117 1.36 8 1.10 0.614 4.08 50.00 0.990 0.960 0.900 0.800 0.667 0.500 0.231 0.091 0.980 1 1 i 7 1 1 1 1 1 1 1 1 1.2.3 COR.( QUIREMENT #3: FLOW CONTROL 1.2.3.1 AREA - SPECIFIC FLOW CONTROL STANDARDS R E Q M T Projects subject to Core Requirement #3 must, at a minimum, comply with one of the three area - specific flow control standards: Level 1, Level 2, or Level 3, whichever applies per the threshold information detailed in this section. ❑ LEVEL 1 FLOW CONTROL Level •1 flow control is a peak- matching performance standard primarily applied in areas where maintaining peak flows is sufficient to protect the natural and constructed conveyance systems that are not sensitive to development- induced increases in runoff volumes and flow durations. King County designates these areas as Level 1 Flow Control Areas. Most Level 1 Flow Control Areas are delineated on the Flow Control Applications Map adopted with this manual (see map pocket on inside of back cover). Any urban - zoned areas of unincorporated King County not shown on this map shall also be considered Level 1 Flow Control Areas. T H R E $ H 0 1. D R E Q M T Threshold The Level 1 flow control standard shall be applied to the design of required flow control facilities for any proposed project which meets one of the following criteria: • The project is located within a Level 1 Flow Control Area as defined above, OR • The project is located within a Level 2 Flow. Control Area as defined on page 1 -32, but does not meet the threshold for application of the Level 2 flow control standard (see p. 1 -33). Performance Criteria Level 1 Flow C evelo ed discharge rate or 2- and 10 -year return perio eak discharge rates to the existing site conditions36 peak Reduced Level 1 Flow Control: A modified version of this standard, controlling only the 10 -year frequency peak flow rate, is allowed if the applicant demonstrates both of the following: • The proposed project site discharges to a conveyance system not subject to erosion that extends from the project discharge point to one of the major receiving waters listed in Table 1.2.3.B (p. 1 -29), AND, • There is no evidence of capacity problems along this conveyance system as determined by offsite °" analysis per Core Requirement #2, or such problems will be resolved prior to project construction. Intent Level 1 flow control is intended to protect flow - carrying capacity and limit increased erosion within the downstream conveyance system for runoff events less than or equal to the 10 -year event. Matching the l- and 10 -year peak flows is intended to prevent increases in return- frequency peak flows less than or equal to the 10 -year peak flow down to the 2 -year peak flow. This level of control is also intended to prevent creation of new "conveyance system nuisance problems" as defined in Section 1.2.2 (p. 1 -21). Effectiveness in Addressing Downstream Problems While the Level 1 flow control standard provides reasonable protection from many development - induced conveyance problems (up to the 10 -year event), it does not prevent increases in runoff volumes or flow durations that tend to aggravate the three types of downstream problems described in Section 1.2.2.1. Consequently, if one or more of these problems are identified through offsite analysis per Core Requirement #2, additional onsite flow control and/or offsite improvements will likely be required (see "Problem- Specific Mitigation Requirements" in Section 1.2.2.2, p. 1 -23). 36 Existing site conditions Is defined in footnote 32 on page 1.27. 1998 Surface Water Design Manual 9/1/98 1 11 1.2.3 CO ( -:QUIREMENT #3: FLOW CONTROL protection, etc.) and shall be within public right -of -way or a public or private drainage easement, AND c) The conveyance system shall have adequate capacity per Core Requirement #4, Conveyance System, for the entire contributing drainage area, assuming build -out conditions to current zoning for the "equivalent area" portion (defined in Figure 1.2.3.A, below) and existing conditions for the remaining area, AND d) The conveyance system will be adequately stabilized to prevent erosion, assuming the same basin conditions as assumed in Criteria (c) above, AND e) The direct discharge proposal will not divert flows from or increase flows to an existing wetland or stream sufficient to cause a significant adverse impact. TABI E=12 3 B MAJOR RECEIVING WATERS • Cedar River • Greeri/Duwamish River below River Mile 6 L K (S. Boeing Access Road) and above SR 18 • Snoqualmie River(includes the North, South, and Middle Forks) • Sammamish River • White /Stuck River • Skykomish River • Tolt River • Lake Meridian • Lake Sawyer • Lake Sammamish • Lake Washington • Puget Sound Note: "Major Receiving Waters" do not include side channels, spring- or groundwater -fed streams, or wetland habitats that provide salmonid spawning or rearing habitat that may be connected or adjacent to major rivers. FIGURE 1.2.3.A EQUIVALENT AREA DEFINITION AND ILLUSTRATION Equivalent area: The area tributary to a direct discharge conveyance system that is contained within an arc formed by the shortest, straight line distance from the conveyance system discharge point to the furthermost point of the proposed project. Basin Boundary Existing Conveyance System Discharge Point • ".if_.= 4.:1 - _ -.._.. Arc .7 Equivalent Area (shaded) Basin Boundary Major Receiving Water 1998 Surface Water Design Manual 1 -29 9/1/98 1 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL FIGURE 3.5.1H 100 -YEAR 24 -HOUR ISOPLUVIALS 3. 1 34 42.6: i ,9 4.� 4. 43 1 44. } 1 r trvAgaro, Oce 100 -YEAR 24 —HOUR PRECIPITATION i 3.4 -^- ISOPLUVIALS OF 100 -YEAR 24-HOUR TOTAL PRECIPITATION IN INCHES 0 1 2 3 4 5 6 7 6Mlles t €€ m ono a OM 8 u ° =gA° °88 o d d d d d d- 000000 0o < Hh < 8 Pq �NFW o W��eo 8 P V 60 n1`:d 9 M� Vry��e.a P o'd �oddd O P y 8 P h E E 06 O 4 4 0d VI N 0 0 z 800 H8 0 00 M M o O o d d O d O O C d 0 G h 8 m p tX X P P O O O O d O d d z 8 „oog000 N N M V1 M V o O d d d d o o d o d b d d d d d d d d Q= P O M M p e Q b - N f0N4� 0 N N 0 N r r r N 0 Odadl�I riT Vivi 0. d O E§§ o O d d d O o 0 o ss000 d C M M M M M M M M 000000.00 d d d d d d d J 888888$8 a 0 w 4 n FI- N 88888888 O f 00 N ^ 60v1� O I� M 601 M N 0 0 0 0 0 0 O .- OO -: G ririri ri riri wi S.en00N 00d000d0 ddddddd 0 0 60800 n h n h P.1 r 60 60 60 60. 5 60 V CJ y - O 00 b 60 d00°80 od0000o 00 M 0 00 00 60 00 o d o- o d O d o d U 0 000000 o ” P 0 N 0000000 18 1=9 gbei4616 e 61658661 1 J 1 1 1 1 11111011111 0 0 0 cn to 3N hAll f 0 ▪ 0 t'4 0 .0 '6! • • • ..... 0 • 0 •11111111•11■1111M1 1 EFL ENV 8 11 frEr 121 EXTENSION 0) 0 0 e n. JW 0 co • 0 0 0 < Z Z z CC 0 ft < w 0 a. 0 2 cc cc < 11. 0 • 1— 11111111111EMEIMINIMI 111111111111111111111111101111111111111 .• . : I . :::• "" ' Lit :4 111111W_ME I I o 41 I NI 4 4 1 , w . 4 ; 1 A • °I ▪ 1• °1 cl g-- T o I4 o 0 0 I I • 8 • g Iw 1 3 1 1 1 I 1 1 7 1 1 Detention Pond Using the program KCRTS and matching the two year and ten year storm, the required capacity is 7810.cubic feet. The effective storage depth is determined to be 4 feet. The size of the detention pond is 25 ft wide by 50 ft long. The pond bottom area is 1250 square feet. The volume required for detention is 7600 cubic feet. Wet Pond In order to meet the 6 months stormwater retention, the volume required for water quality is 8200 cubic feet. This was determined by setting the rainfall as 0.64 of the two year 24 hour rainfall. The total volume of the wet pond and dry pond is the total of wet pond and detention pond volumes. The volume of the detention pond from level 86 ft to 92 ft is estimated to be 16,300 cubic feet. Conveyance Systems The capacity of the 8 inch pipe at a 1 % slope is about 0.55 cfs. The general site has a slope of more than 5% grade and thus the conveyance will have ample capacity to carry the flow from the stormwater and would not back up. The conveyance system's calculation is attached. 1 Special Provisions 8 -32 MODULAR BLOCK RETAINING WALL 8 -32.1 Description SP -19 New New This work shall consist of design and construction of modular block retaining wall reinforced with Tensar Geogrids. Modular block walls shall be Mesa High Performance Retaining Wall Systems as supplied by Mutual Materials Co. of Bellevue. Submittal The Contractor shall submit detailed design calculations and shop drawings to the Engineer for review at least 14 days prior to the start of wall construction. The submittals shall include design calculations and all details, dimensions, quantities, and cross - sections necessary to construct the wall. The design calculations shall be based on the current version of AASHTO Standard Specifications for Highway Bridges. The factor of safety for overturning and sliding are 2.0 and 1.5 respectively for AASHTO Load Group 1 and 1.5 and 1.1 respectively for AASHTO Load Group VII. The design requirements for the retaining wall are contained in the Project Geotechnical Report found in Appendix C. A minimum of three sets of shop drawings (size 22 inches X 34 inches) shall be submitted and shall include an elevation view of the wall, all details for connections of the reinforcing to the modular block wall. The plans and calculations shall be prepared and sealed by a Professional - Civil Engineer registered in the State of Washington. 8.32.2 Materials New s. Cementitious Materials shall be Portland Cement ASTM C150. Aggregates use in the manufacture of modular block wall shall be normal weight aggregates conforming to ASTM C33. Mesa Segmental Concrete Facing Unit shall be manufactured by Mutual Materials, Co. of Bellevue and shall be the equivalent of Cornerstone Blocks. Tensar Structural Geogrid shall be manufactured by The Tensar Corporation, Morrow, and GA. 8.32.3 Construction Requirements New All modular block units shall be sound and free of cracks or other defects that would interfere with the proper placing of the unit or significantly impair the strength or permanence of the construction. Exposed faces of the Modular Block Units shall be free of chips, cracks or other imperfections when viewed from a distance of 30 feet under diffused lighting. Wall Excavation RECEIVED Wall excavation shall be in accordance with the requirements of Section 221n p mirAformity and construction stages shown on the plans. The foundation for the stru ct�iI shall lid4ljraded level for a width equal to or exceeding the length of reinforcing as shown on iyttmp[9'ed shop PUBLIC WORKS Special Provisions SP -20 drawings. Prior to wall construction, the foundation, if not in rock, shall be compacted as directed by the Engineer. Any foundation soils found to be unsuitable shall be removed and replaced as provided for under Section 2- 09.3(1)C. The Clearing and grubbing shall be in accordance with Section 2 -01.3 Embankment construction shall be in accordance with Section 2- 03.3(14). Compaction method shall be in accordance with Section 2 -03.3 (14) B. Backfill Placement Backfill placement shall closely follow erection of each course of segmental wall units. Backfill shall be placed in such a manner as to avoid any damage or disturbance to the wall materials or misalignment of the panels. Any wall materials which become damaged or disturbed during backfill placement shall be either removed and replaced at the Contractor's expense or repaired and corrected as directed by the Engineer. The moisture content of the backfill material prior to and during compaction shall be uniformly distributed throughout each layer of material: 1. The moisture content of all backfill material shall meet the requirements of Section 2- 03.3(14)C, Method C. 2. Backfill material with a placement moisture content in excess of 2 % beyond the optimum moisture content shall be removed and reworked until the moisture content is acceptable through the entire lift. 3. The Optimum Moisture Content shall be determined in accordance with ASTM D1557. Backfill shall be compacted to 95 %of the maximum dry density as specified under compacting earth embankments, Method C in Section 2- 03.3(14) C except as modified herein: 1. The maximum lift thickness after compaction shall not exceed 10 inches. 2. The Contractor shall decrease this lift thickness, if necessary, to obtain the specified density. 3. Compaction within 3 feet of the back of the wall units shall be achieved using either a backfill rammer tamper or a vibratory plate compactor. } Retaining Wall System PILE COPY I understand that the Plan Check _ :ct to errors and omissions and does not authoda the violation of 4.• ,;tod code or ordnIMIL Receipt of contractor's of apprond pity MInowledged. K 'to No.._' .t. ..Le :01, ,w MESA Retaining Wall System Construction & Quality Control Manual The contents of this manual should be thoroughly reviewed by the parties in charge of wall construction before initiating the project. © 1995, Tensar Earth Technologies, Inc. 5775 -B Glenridge Drive d Suite 450 Atlanta, GA 30328 CITY RECEIVED LA SEP n 7 gaga ak — - — 1. Purpose This manual for the Tensar MesaTM Retaining Wall System is provided as a guideline for the construc- tion and the quality control of the installation. The manual shall be provided to the owner's engineer, the construction quality assurance inspector, and the contractor. 2. 11. Responsibilities For Construction Compliance • The contractor is ultimately charged with pro- 3. viding construction in accordance with the con- tract documents, plans and specifications. The contractor is also responsible for the verification of line, grade and other physical features. • The engineer is solely charged with the enforce- ment of the contract plans, documents and spec- ifications. • The Mesa technical representative may assist the contractor and the inspection staff on the recommended procedures within the guidelines of this manual and the contract documents, plans and specifications. The representatives are there at the start of wall construction and thereafter only as requested and necessary. 111. Materials & Handling A. Supplied Materials 1. Tensar Uniaxial and Biaxial Geogrids 2. Tensar drainage composite and piping (where required on the wall plans). 3. Tensar Mesa concrete facing units and FS2.0TM connector bars. 4. Tensar Mesa cap units and cap adhesive (where required by the wall plans). 5. Geotextile filter materials (where required by the wall plans). B. Handling Wall Materials 1. The concrete facing units will be delivered on pallets and are to be off - loaded by the contrac- tor. The transporting equipment must be pro- vided firm ground on which to travel and a rea- sonably stable and level area to off -load. A fork lift or a loader fitted with forks are normally used to handle the pallets. Pallets are the proper- ty of the block manufacturer and must be stored by the contractor for pick -up by the block manufacturer. If the ground on which the pallets are to be placed has not been stabilized, the contractor shall provide protection from staining or discoloration of the units caused by rain splash. This can be accomplished by using wood dunnage and polyethylene sheet film. The FS2.0TM connection bars used to attach the geogrid to the facing units will be shipped in cardboard cartons and shall be stored in a secure and dry location. The Tensar geogrids will be shipped in roll form on flatbeds or in box trailers. The contrac- tor is responsible for off - loading. The rolls should be stored in a secure area. Each roll will be labeled as to its type (e.g.. UX 1400, UX1500, BX 1200, etc.), its lot number, and its roll number. The standard roll size of the uniaxial geogrids will be 4.3 feet wide by 200 or 250 feet long (see Figure A). The rolls weigh between 83 and 178 pounds depending on the geogrid type. It is advisable that the contractor color code the roll types with spray paint immedi- ately after off - loading. FIGURE A 4. Additional information and Guidance • It is the contractor's responsibility to verify the quantities shipped and the general condition of the materials before accepting delivery. The contractor shall immediately notify the Tensar representative if there are any problems relating to the delivered materials. • The contractor will inventory the materials sup- plied to assure that sufficient quantities, as determined by the approved plans, have been supplied to avoid construction delays. • The contractor is allowed two hours to off load materials. FIGURE B • The contractor shall receive certifications the geogrid and FS2.0TM connectors with each shipment. It is the contractor's responsibility to ensure that the information is furnished to the engineer (see Figure B). C. Contractor Supplied Materials 1. Tools • Dead Blow Hammer • Large Flathead for • Screw Driver • Broom 4' Level • 9" level • Concrete Cut -off Saw • • Chalk Line • Masonry String Line • Pitchfork ( optional to secure geogrid) •2' or 2. Materials • All cast -in -place concrete and structural compo- nents not specifically included in the quote. • Stone filter medium • Reinforced or select fill • Wooden stakes or pins used to remove the slack from the geogrid unless pitchfork is used. 3. All labor, equipment and supervision necessary to perform the total wall construction. IV. Preparatory Work for Wail Construction A. Verify approval of unit and reinforced fills. B. Review the drawings to plan the geogrid layout (see sample construction drawing in Figure C). C. Prepare the subgrade by excavating vertical- ly to the plan elevation and horizontally to the design geogrid lengths as indicated in the con- tract documents. If a rock face is shown on the plans it is the responsibility of the engineer to determine the competency of the rock at the limits of excavation shown on those plans. t5 Ji r,, El J'1 £i•i ni.SS...ti ll i:t,. :a�,c� ::t:. .11. .t It. .1..1 1 1 5.: •I'11.I +.:1.1'7 .•...'•�:'ll : t : '..J 4444. •(.1 .. .. r,...... •••4444 t...... .1 ..Irl" . «r llwt. ww irrc (Ia ', 1.1 ,•s4 f, -•,„ 1 1 !t• + 1 •�: t +• • Y•.--- -4'- --1... iU3 (f +r•• nwwrrrM..N rww ... __- .......,.. ...t:l..r).:.o —•.i ..r_ - .•144 ., w M. 4.9•4•14 44 4.4.4 •14 r..—w tiM .4 .414...• r 4}44•...• w • .4 ar...r•t.1.15,1114 4 444 ••• •- 4.14.4•+- r•••••••!,t•14!7.:34 .- }..w•.. ,w`'•••••••••••..,- _•_".•• •• ••-+•--•— rt ..151h.- ...p•.•M...r.........r r..•.•..•...•.»•.••••4_..... ■ ' .'..�. 44.4.... ...,• : • • t. I•• • • I . • .: I . i'i:'t . ; ". • l•?.li; ..! Si.130•_._ ttt.ri;' lj- •-.._.. 4444 »4444_._. 001 :34,0:3i3 - 44_44.4.•. . t tlti ii •s .40 1110 ( {, 1')S.) Mitt !AV l/r i). !;14:114Lt2 It.V:t C1'!Ata 1:: I'ViiP1.111y.! I eAt7vs OR CEO:** .i:jil4Itis70:41 : 011:A(t (Y: t' ). 1V.Y4:t::: i!MAU 2W4: li CECT:16: il•MVit %ti:. C• ::lirAgi) Ai-010X. raitNt'tt10 ur. i rAS i :riil;t!MOri FIGURE C Any deviation in the location of the rock face with respect to the face of the retaining wall may require an adjustment to the geogrid design and the designer of records must be notified by the contractor prior to proceeding with the wall construction. The subgrade shall be approved before proceed- ing with the retaining wall construction. Any foundation soils found to be unsuitable by the engineer shall be treated in a manner approved by him to obtain the required bearing value. D. On larger projects it is helpful to cut the geogrid in advance of wall erection. This will speed wall erection by eliminating one sequence during construction. See Figures D and E for calculating, measuring and cutting of the geogrid. I�,•,( ;± U;Ncl .rte yi Y011110• • Armor ter. 4�fti1Gt11� E•ET`167C-; PER D7 O.11ANG {;JT37L:I`!".k5);NEWEL"? 7R?ht;S'v'ENSE FIGURE 0 CUTTING SCHEDULE STA..STA. GRID TYPE GEL (FT) WALL LENGTI- NO. OF PIECEE. 1+ 26.1 +68 TYPE A 11.5 42 '30 • TYPE B • " 20 TYPE C 10 1 +68.1 +86.7 TYPE A 10.5 18.7 15 TYPE B 10 • TYPE C 0 SAMPLE CALCULATION •42.0 LF / 4.3FT (ROLL WIDTH) . "9.77 USE 10 10 PCS/LAYER X 3 LAYERS . 30 PCS " Where the calculation has a remainder such as..77 it hsall be rounded u The grid with the longer GEL shall be extended Into the reinforcing area with the shorter GEL (Geogrid Embedment Length). FIGURE E E. The leveling pad shall consist of unrein- forced concrete or as otherwise indicated in the contract documents. The leveling pad is typical- ly poured six (6) inches wider (3" on each side) than the nominal block dimension to allow for wall• curvature and ensure full bearing for the bottom units. It is very important the leveling pad be accurately placed to minimize problems in placing the facing units. The sides of the pad should be formed with the top of the form panel equal to the top of the pad (see Figure F). The standard Mesa unit is 7 -5/8" or 0.635' in height. An allowance for shimming and the thickness of the geogrid may require the adjustment of the actual leveling pad grade. The elevation of the top of the masonry unit should be shot and the pad grade adjusted based on that information. During wall construction it is recommended that the elevation of the leveling pad in place does not exceed the in place wall elevation by more than four courses. FIGURE F Wall Construction Wall line should be established using a string line and/or a chalk line, if working on a con- crete pad. The bottom course must be accurate- ly placed, carefully spaced and leveled to facili- tate construction and enhance the appearance of the wall. Whenever possible, begin the wall construction at the lowest portion of the leveling pad. This is particularly important when erecting a wall with a set back or battered face due to wall alignment translations with height. Prior to the installation of the second course and each successive course the tops of the units on which the course is to be placed must be swept clean. Failure to take the time to do this will result in problems with seating c and leveling the units, and the likelihood of cracks developing in the units due to load con- centrations as additional courses are set. The units are stacked in a running bond fashion, the same as with standard masonry wall construc- tion. The units, once placed, shall be advanced forward, toward the face of the wall, until they fully contact FS2.0TM connector bar (see note E for details). C. The stone drainage material is placed to the limits shown on the drawings. The stone drainage material does not have to be placed within the front core. The proper installation of the drainage material is critical to the overall wall performance. Therefore, it is imperative that it be installed properly and protected during wall construction. D. As subsequent courses of facing units are placed it is important that the units remain level from back to front (see Figure G). This level should be checked as each course is placed. If the units are more than 1/4" out of level over the units tail to face dimension, they should be brought to level by inserting approved shims. Cut -off pieces of the geogrid reinforce- ment work well. FIGURE G NOTE: The Mesa units can be stacked several units high prior to the fill placement. The geogrids are flipped over the face of the wall until the fill reaches the level of the reinforcement. A string line should be pulled after each course has been set to ensure that the geometry of wall is being maintained. The string can be refer- enced from the core, slot or the tail of the unit as shown on Figure H. FIGURE H E. At the location and elevation shown of the plans, install the Tensar uniaxial or biaxial geogrid of the type and length shown on the plans. Place the transverse bar in the location shown in Figure I. Place the fingers of the con - nector bar such that they pass through the geogrid openings and to the rear of the first transverse bar (see Figure J). The fingers of the FS2.0TM must engage each geogrid aperture for continuous bearing and it must span the space between adjacent units to provide horizontal alignment (see Figure K). A minimum of two fingers must be engaged in each adjacent modu- lar unit. Use a hand hammer to seat the con- nector bar in the groove at the top of the unit. A 2 x 4 block, used as a setting tool, facilitates the installation of the connector. Slack must be removed from the geogrid prior to final seating of the connector bar. 4 FACE OF YIA_I. COMB'. 11K HAH — RANSVF,H9e EAR WirtIAIEHS H MESA bLO KS FIGURE I FIGURE J NOTE: The transverse bar with the fingers removed is placed on the facing unit. On facing courses which do not require geogrid reinforcement the FS2.0 m connector shall be broken in approximately thirds. The 1 / 3 con- nector shall be spaced evenly between the two adjacent units and driven into the slot. It is important that the tabs on the top of the FS2.0Tm are oriented in the proper direction for a set- back or vertical wall (see Figure K). The grade under the geogrid shall have been compacted to the required density and graded reasonably smooth. Remove the slack from the geogrid by pulling and then anchoring it using pins or stakes. The pins used to position the tail of the geogrid, can be withdrawn once the fill has been placed and then reused on subsequent lifts. Optimally, a pitchfork can be inserted at the tail of the geogrid and the slack removed by prying until the fill has been placed on the geo- grid as shown in Figure M. The removal of the slack from the geogrid prior to placement of the fill will prevent movement of the wall facing due to translation of the slack toward the facing. FIGURE K FIGURE 41 F. Fill placement shall be performed to mini- mize development of slack in the geogrid. The fill should be spread in a direction away from or parallel to the face of the wall. In this way any slack that does develop, will tend to be shoved toward the free end of the geogrid. Unless the Contract Documents are more strin- gent, the reinforced fill lifts shall not exceed six (6) inches where hand compaction equipment is used or ten (10) inches where heavy compaction equipment is used. These thickness may vary depending on the project specific soil types used. The fill shall be compacted to 95% of ASTM D -698 or as required by the contract documents, whichever is greater. Only light- weight compaction equipment will be used within two (2) feet of the tails of the units. Tracked construction equipment shall not be operated on the geogrid. Rubber tired equipment may be operated on the geogrid providing the subgrade is not pumping or rutting. Turning of tired equipment shall be minimized to prevent dislocation or damage to the geogrid. The equipment must travel slowly and with suffi- cient care to avoid dislocating the geogrid. At the end of each day the contractor must ensure that the reinforced backfill is graded to drain away from the face of the wall and that the berms or ditches are in place and functioning to prevent the entrance of runoff into the wall con- struction site. G. The cap units, if required, are installed by gluing the units below using an approved con- struction adhesive. H. Wall penetrations may be accommodated by cutting the blocks to fit, using a pipe cutoff saw and a mason's hammer. The small voids, less than one (1) inch, can then be closed with cement and sand mix or other methods approved by the engineer. VI. DEFINITIONS Contract Documents: The agreement between the owner and the contractor including condi- tions of the contract drawings, specifications, and the provisions, of the agreement between the contractor and the supplier of the Mesa sys- tem; and shall include addenda and other modi- fications issued prior to the execution of the contract. Contractor: The individual, firm, or corporation, acting directly through its agents or employees to undertake the executive of the work under the terms of the contract. Engineer: The owner designated person(s) with authoritative charge over certain engineering functions and responsibilities. Owner: The owner of the project with whom a contract has been made for payment for the work performed under the terms of that contract. Plans: The part of the contract documents consist- ing of the approved plans, profiles, typical cross sections, working drawings and supplemental drawings, or exact reproductions thereof, which show the location, character, dimensions and details of the work to be performed. Specifications: A description of the quality and quantity of the materials and workmanship that will be required of the contractor in the execu- tion of the Work under the contract between the owner and the contractor. Work: All work to be performed by the contractor unless the terms and conditions of the contract as are necessary to fulfill the obligations of said contract. Inspector: The authorized representative assigned to see that the workmanship and materials are in accordance with the terms of the contract. TENS R Tensar Earth Technologies, Inc. 5775 -B Glenridge Drive - Suite 450 Atlanta, GA 30318 404/250 -1290 Tensar Geogrids are manufactured under the protection of U.S. Patent #4,374,798. Other patents pending. © 1995, The Tensar Corporation. Tensar is a registered trademark. Printed in the U.S.A. The information contained herein has been carefully compiled by The Tensar Corporation and to the best of our knowledge accurately represents Tensar product use in the applications which are illustrated. Final determi- nation of the suitability of any information or material for the use contemplated and its manner of use is the sole responsibility of the user. IG- MESA -6/95 z W z M• N POTHOLE EX. E' SANITARY SEVER PROP. 10' WDE ACCESS ROAD TO POND • 1 ( jor. HALL uriEnor (i) �► '� 70 � I —/ 2411110111AVINEMVSMA II Ady1,, // /1 1 I 1•I {--- PRIVACY FENCE r SCUP TM / 24•11P / 1 1e'uv I it /Arm! ,aaior4r, matt yn MMALFSIE //• =12 "CPS �� I fc� +T��Il��►-�c�c III �. � �' r °I' I L 1 �M Ci0+U000 q�G `� \ SLR Mtw1. �\ _ J �gR- O¢M�C-NIL CM,.c�.1NU0[0 / NEI 1♦^ \ , -• / �� / PAKNLNt L M. [ i1e 1 � I / 5 �', � 1` B•uP i I 100— '< I Li. ASPHALT I EX [[1Rµ501 , 1[CRC. CURB 1 i IIILE� S -mUCT. ; 1 ; Zr \- u � EYERGENCY OVERFLOW CONNECT TO EX. SWALE El. CS A. IM MO LANE • CONC. CURB TUKYALA CITY HALL XEROX BUILDING. 6300 BUILDING 8 P UBLI C WORK" ,S4 .1:) n.E. =' T •ENGINEERING •STREE Roth Hill Engineering Partners. Inc. 14410 NE 3I111PYB0 11101 Roth ill T CITY 1 GRAD POTHOLE EX. r SANITARY SEWER PROP. 10' WIDE ACCESS ROAD TO POND CP aliiimulafiffitra...,--taa. P. .2,.. ....,,,AIL.-...tarN -itr-illiiiiiiiifaiiiiikir4 .�Ir' I �� �(s IIOCKCRT I I 1 1 26•/ 1 !` ET SI IJCT, : \ t I ' 116. I I'i"! /// ! Its ! / / 1R11 64 / t�� I III ;.� `,4i,AA _!;,'� rl wl1191111 I 5 s,( / 1 � ,nr - 6.144 Arwiirdwromordia ger _,._., a.,. �r��ry i ���ar 21 N 122 k2121000 CCNC. 0922 IHLEt STRUCT. 1 1 I • • • 5~44 `- EMERGENCY OVERFLOW CONNECT 10 EX. SWALE 1 0( C f nv.l 0 { � V XEROX BUILDING _ erg Ikon 9111 Pro) DI MN FW pI 30 0 3P 14142.511 6/6/1000 SCALE 0 FEET RECEIVED CITY OF TUKWILA SEP 0 7 1999 PERMIT .CENTER Roth Hill Engineering RothHill Partners, Inc, 14450 NE 2M, Pio 1101 e6M1u, Wwira 11001 Tel 43111111.114411 Fa 421,111.1110 CITY HALL PARKING LOT EXPANSION PROJECT NO.,` 95-13001 GRADING & "8TORik,DRAINAGE PLAN r, un 11/3/1006 1.1 3 f a 1 ■ 1 • 1 81 (13, No Deb INIilias Fiio No 98 -00' kik .1 " =30'' I AMIN CITY OF TLCWILA ( ' . 6200 Southcenter Boulevard, Tukwila, Washington 98188 .41111416 (206) 433-1800 MEMORANDUM TO. FROM: 50 AA DATE slisloo SUBJECT: .40/1/Yhil MTqq-o/Sco. 1.4 ia May 5, 2000 City of Tukwila Steven M. Mullet, Mayor Department of Community Development Steve Lancaster, Director Scott Moore 6300 Southcenter Blvd Tukwila Wa 98188 RE: Permit Status MI99 -0156 15447 65th Ave S Dear Mr Moore: In reviewing our current permit files, it appears that your permit to construct a modular block retaining wall, issued on September 14, 1999, has not received a final inspection as of the date of this letter by the City of Tukwila Building Division. Per the Uniform Building Code and /or Uniform Mechanical Code, every permit issued by the building official under the provision of this code shall expire by limitation and become null and void if the building or work authorized by such permit is not commenced within 180 days from the date of such permit, or if the building or work authorized by such permit is suspended or abandoned at any time after the work is commenced for a period of 180 days. Based on the above, if a final inspection is not called for within ten (10) business days from the date of this letter, the Permit Center will close your file and the work completed to date will be considered non - complying and not in conformance with the Uniform Building Code and/or Mechanical Code. Please contact the Permit Center at (206)433 -7165 if you wish to schedule a final inspection. Thank you for your cooperation in this matter. Sincerely, ciR,-)04 Bill Rambo Permit Technician Xc: Permit File No. MI99 -0156 Duane Griffin, Building Official C: City of Tukwila John W. Rants, Mayor Department of Community Development Steve Lancaster, Director MEMORANDUM January, 11, 2000 TO: Bob Giberson, Senior Engineer Scott Moore, Publi Wo ector FM: Carol Lumb, Asso lanner RE: Minor Modification to City Hall Parking Lot Landscaping Plan (File #L98 -0089) This memorandum is to confirm my discussion and site visit today with Scott regarding the relocation of three deciduous trees on the eastern edge of the new King County Housing Authority parking lot, as noted on the attached landscape plan. Because several large trees were retained along the eastern edge of the Housing Authority parking lot, you are proposing to relocate the three deciduous trees that were to be planted there to the east, approximately 20 feet, to an area where there is currently no vegetation or trees. This modification is proposed because the retained trees' canopy will hinder the growth of the trees that were to be planted. This minor modification to the landscaping plan is approved. If you have any questions, please call me at 431-3661, Attachment: Portion Landscaping Plan cc: Jack Pace, Planning Manager Files: MI99 -0156, .L98 -0089 as 1 gal, 3' o.c. Full Form 1 gal. 3' o.c. ROUND COVER) Size Full Form Saacln Comments 'eNS Metho »e a 1 gal. 18" o.c. Full Form ,lis'Blue Chip' 1 gal 18" o.c. Full Form sNs 0 2S Bst i 9 20.90'- 80 24"CE ro'Ww_ "'A 4.16 56'4488°19'47 'W • • EX am. Can 1 1 1 PLANTING NOTES DRIVEWAY 1 2 3 4 5 Contractor shall be responsible for familiarizing.himseit Itp.,!li other site improvements prior to starting landscape work. Contractor shall use caution while excavating to avoid disturbing any existing underground utilities. If active utilities are encountered, contractor is to promptly advise General Contractor and Owner. Contractor shell maintain and water plant material until owner's final acceptance is received In writing. Contractor shall be responsible for providing the quantity of plants that are represented by symbols on the drawing. Contractor shall be responsible for computing specific quantities of groundcover, and plant material utilizing on•center spacing for plants es shown on plant schedule and minimum planting distances as specified below. Ground cover shall be planted In equilateral trlangularspacing pattern at the on, center distances es shown. Where ground cover abuts curbing, walkways, signs or masa minimum ntantlnn dlttanea alma ha i1!! Item plantar el Mani in eurhtnn wince 15'. Drip iMi will lot "+•O 44 j et .— Mahvria g �l' .119 'Blue Chip' 1 gal. .-- 18" o.c. Full Form rsr •N88 °1'41 W r -1 X02:. r �( ..11• .��' /' •,4 E ' ' ••, 24, CE 4"CW r io WW "-- --y' 4.16 56' -N88 °19'47 'W IV cccic►o•n -4 1 PICAL SECTION ■T TO SCALE r / <O PLANTING NOTES DRIVEWAY 1. Contractor shall be responsible for famillarizing.himselLw!ith.,all other site improvements prior to starting landscape work, 2. Contractor shall use caution while excavating to avoid disturbing any existing underground utilities. If active utilities are encountered, contractor Is to promptly advise General Contractor and Owner, 3, Contractor shell maintain and water plant material until owner's final acceptance is received In writing. 4 Contractor shall be responsible for providing the quantity of plants that are represented by symbols on the drawing. 5 Contractor shall be responsible for computing specific quantities of groundcover, and plant material utilizing on- center spacing for plants as shown on plant schedule and minimum planting distances as specified below. 8. Ground cover shall be planted in equilateral triangular :pacing pattern at the on- center distances as shown. Where ground cover abuts curbing, walkways, signs or poles, minimum planting distance shall be 12" from center of plant to curbing, walks, etc. Minimum planting distances shell be 15" from center of all trees. i . Subgrade to within 1/10 foot provided by General Contractor at the following. a. Planting beds: 8" below finish grade b. Sod fawn areas: 8" below finish grade • 8. Provide topsoil rototilled to a depth to 12" below finish grade as follows. e. Planting beds: 8" depth of topsoil b. Sod lawn areas: 8 "depth of topsoil I5. UNDIaTURBED NATIVE SOIL 2 TIMES I 3. Topsoil shall be a mix of organic matter and soil (composted sawdust, manure, sandy loan, and loam soils) with emendements as recommended by soil testing lab. 10. Lawn finish grade shall be flush with adjacent sidewalk or back of curb grade. 11. 2" depth mulch In all planting beds, Sfll NT; ri 99/14/1999 13:32 4252276 pm. amp mi PHILIP SERVICES C O R P. DATE: R-114—ek CI TO: io E InQY TO: TO: FROM: DANE .Q t . (\ S PHILIP SVCS SE( '_E e r4wiM FACSIMILE PROJECT NUMBER PH: PAGE 01 cvi fir' OMMUNICATION47,,$-- RECEIVED ¢tilf SEP1419ag PU8L1CWORKS FAX PR: FAX P11: FAX Direct Phone: (425) w2- ° La NUMBER OF PAGES, INCLUDING COVER SHEET Original will Regular follow by: Mail MESSAGE /COMMENTS Hand Delivery ni Overnight g will not follow The document(s) with this transmission are only for recipients) named above and may contain privileged/confidential information. Uneuthorirsd disclosure, dissemination, copying of this transmission is strictly prohibited. If received to error, please destroy. If there are any questions /problems with this transmission, please contact the sender. Philip Environmental Services Corporation A Subsidiary of Pirilin Sarvice. Corn_ 09/14/1999 13:32 42522761°' P 14 '99 09! 25 TUKWL.... DCD /PW W ILA, v ; til� At i U M.'' 190S PHILIP SVCS SEATTLE PAGE 02 P. 1/1 City of Tukwila Public Works Department(Engineering Division FAX TRANSMITTAL Fax Number: (206) 431 -3665 To: Dave Hopkins Date: September 14, 1999 Title: Company: From: Bob Giberson Philip Environmental Services Title: Dept Division: Fax Number: 425 -227 -6146 Total # of pages transmitted, including this cover skeet: 1 Sent by (initials): [Subject: City Hall Parking Lot Expansion project Message/ RE: Retaining Wall Building Permit Comments Tukwila Public Works has secured a building permit for your approved MESA Retaining Wall Design, at our time and expense. In order to finalize the permit 1 need a copy of your Washington Contractor's License or an affidavit in a form acceptable to the Tukwila Building Department. Q /fe Vca, Thanks! P e r , / o w . , '-e "e ,'/ ' 9, c6 CC: SCOTT MOORE FILE: 95- B001 -12 moo ..1_..........•.. 1,.11.1. 1.111 ... • 11 ••• • 1 . 4.41 .�.. ..11 1.., .. . ...; ., ...x...11.., • �.�.. ' 1 - — - -- 1 • ' ' . • I . 1 • • • 1 ,.! 11 144 coinnsuntcotion is not clerir& received; jleasi call'(206),43.1,!0179:. ' • :1 Tukwila Public Works Deportment - 6300 Soutmcenier .11M114100, Tukwila, �WA 98188 • " 111 : _ ,1 City of Tukwila John W. Rants, Mayor Department of Community Development Steve Lancaster, Director September 7, 1999 Bob Giberson 6300 Southcenter BI, Suite 100 Tukwila, WA 98188 RE: Letter of Incomplete Application #1 Development Permit Application Number MI99 -0156 City Hall Parking Lot Expansion 15447 — 65th Avenue S Dear Mr. Giberson: This letter is to iriform you that your permit application received at the City of Tukwila Permit Center on August 16, 1999 is determined to be incomplete. Before your permit application can begin the plan review process the following items need to be addressed. Building Division: Ken Nelsen, Plans Examiner, at (206)431 -3677, if you have any questions regarding the following: 1. Manufacturer specification required for `mesa' H.P. retaining wall system. 2. Required drainage behind wall not shown on site plan, must drain to approved location. The City requires that four (4) complete sets of revised plans be resubmitted with the appropriate revision block. If your revision does not require revised plans but requires additional reports or other documentation, please submit four (4) copies of each document. In order to better expedite your resubmittal a `Revision Sheet' must accompany every resubmittal. I have enclosed one for your convenience. Revisions must be made in person and will not be accepted through the mail or by a messenger service. If you have any questions, please contact me at the Permit Center at (206)431 -3672. Sincerely, 1/V6/— Brenda Holt Permit Coordinator encl File: Permit File No. M199 -0156 • +r; Porry-1-1;-- Nod Cb-p9 PLAN REVIEW /ROUTING SLIP ACTIVITY NUMBER: MI99 -0156 DATE: 9 -7 -99 PROJECT NAME: CITY HALL PARKING LOT EXPANSION Original Plan Submittal XX Response to Incomplete Letter # 1 Response to Correction Letter # Revision # _ After Permit Is Issued DEPARTMENTS: B ilding Division iz 1-'1- Public Works Fire Prevention Structural Planning Division Permit Coordinator DETERMINATION OF COMPLETENESS: (Tues., Thurs.) DUE DATE: 9 -9 -99 Complete n Incomplete Not Applicable Comments:'' \\ TUES /THURS ROUTING: Please Route Structural Review Required No further Review Required n REVIEWER'S INITIALS: DATE: APPROVALS OR CORRECTIONS: (ten days) Approved Approved with Conditions Pal DUE DATE 10-7-99 Not Approved (attach comments) n REVIEWER'S INITIALS: DATE: CORRECTION DETERMINATION: DUE DATE Approved Approved with Conditions U Not Approved (attach comments) n REVIEWER'S INITIALS: DATE: \PRROUTE.DOC e Inn City of Tukwila John W. Rants, Mayor Department of Community Development Steve Lancaster, Director Revision submittals must be submitted in person al the Permit Center. Revisions will not be accepted through the mail, fax, etc. Date: Plan Check/Permit Number: IC Response to Incomplete Letter # ' Response to Correction Letter # Revision # after Permit is Issued Project Name: Project Address: Contact Person: Mi'1'1 0Ko 44kbut Payki laf &moist 7 Avis Phone Number: Summary of Revision: 4fribi Alo.kii pit Sheet Number(s): "Cloud" or highlight all areas of revision including date ofirrevvissiion Received at the City of Tukwila Permit Center by: (Entered in Sierra on I MI Cai'V 040 q-17'-11 OSN 06/29/99 09/1.4/1999 13:32 425227619 -- PHILIP SVGS SEAT r. . Detach And Display Ccrtilicate PAGE 03 F i2 .0i2•UVO tti/971 DEPARTMENT OF LABOR AND INDUSTRIES REGISTERED AS PROVIDED BY LAW AS CONST CONT SPECIALTY . .. REGIST. # CCWDEX PHILIE8044LF EFFECTIVE DATE PHILIP ENVIRONMENTAL 20 BOX 3552 SEATTLE WA 98124 EXP. DATE 10/31/1999 06/06/1996 SRVC CORP Detach And Display Crnitit.atu. REGISTERED AS PROVIDED BY LAW AS1 CONST CONT SPECIALTY REGIST. # EXP. DATE CCWDEX PHILIESO44LF 10/31/1999 EFFECTIVE DATE 06/06/1996 PHILIP ENVIRONMENTAL SRVC CORP PO BOX 3552 SEATTLE WA 98124 Signature, Issued by DEPARTMENT OF LABOR AND INDUSTRIES Please Remove And Sign Idencificadon Card Before Placing In Billfold