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Home My WebLink About03573 - Technical Information Report i - � � m ENGINEERING REPORT Teclmicr�l lriforrlintion Report Renton Memorial Stadium September 7,ZO10 � � . � RECEj�jED OCT 2 6 2010 PREPARED FOR: Renton School District B�ILDING ��f�S10�1 300 SW 7w Street Renton,WA 98057 (425)24�-2300 PREPARED THROUGH: �� C� A Bassetti Arcltitects �� 71 Columbia Atreet,Suite 500 4'� �'��R�`�� Seattle,WA 98104 y��v Phone:(206)3=40-9500 J�, Contac�Colbi Cannon 0�,�'��-Fy'��'��w�'� I � •� ssI�NAL E�G + PREPARED BY: n COUGHLINPORTERLUNDEEN ��l� 413 Pine Street,Suite 300 j— \ 1� Seattle,�b'ashington 98101 � � P:206/343-0460 1 1� Contact: Sean Robertson,P.E. �,� � �� _� 000 �-.� 3 5 73 i TECHNICAL INFORMATION REPORT AND HYDROLOGIC ANALYSIS Renton 1�lemorial Stadium Coughlin Porter Lundeen Project No.C09006�-05 September 7,2010 TABLE OF CONTENTS Section Page I. PROJECT OVERVIEW.................................................................................................................................................1 GE:NI:RAL DESCRIP"I I()1�..................................................................................................................................................... 1 EXIS'I'I!�G CONDITIONS....................................................................................................................................................... 1 PROPOSED DR.AI'�:1GF SYST[h1.......................................................................................................................................... I It. CONDITIONS AIYD REQUIREMENTS SUMMARY.....................................................................................2 KI�(;COU\Tl'Sl'RI�ACf=WATER'.VI:1\AGE�IEVT DI:SIGN h1A\I�AL CORE REQI IRE:�1ENTS:...........................................Z SPf:�'IAL.REQUIR��1EN I S:..................................................................................................................................................2 PRO.II'C'I SPECIFIC RFQUIRE!�1ENTS:...................................................................................................................................2 I11. OFF-SITE ANALYSIS..........................................................................................................................................3 T:1SF: 1 —STliDY ArtE��D�F�N�T�ov:at�[�Mt�r�s................................................................................................................3 T.as�:2-REsouRCE.REviE�� .............................................................................................................................................3 T:�sh 3-FiE��I�v�N[:c'T�iov...............................................................................................................................................3 TASF:4-DRAIVAGI:SYSTEA9 DESCRIPiION:1\D PROBLE\4 DF.SCRIPTIONS......................................................................3 UPtiTRFAh7A\.4L1'SIS........................................................................................................................................................� D()�4'NSTREAM ANAI.YSIS..................................................................................................................................................? T;\SI� 1—MITIGr1llON OF=E`iISTI�G C)R POTFNTIAL PROBLEMS........................................................................................�3 ' IV. FLOW CO�TROL AND WATER QI;ALITY' FACILITY ANALYSIS AND DESIGN.............................5 E��sr�!vc;SITE H11)ROL(K�l'(PARI A)..............................................................................................................................` Dt:vi:t.c�r�r�Srrf.Hti[�kc�i_cx;v(P,aa r B)..........................................................................................................................� PIRFORh1.A�10E STANU:IRDS.AVD FLO11 CO�ITROL SYSff:\i(PARTS C.A\D D)................................................................� V1�'A fkiR QUALITY SY'STEM11(P.ART E)..................................................................................................................................6 STA'JD:1RD REQUIRF.�4ENTS...............................................................................................................................................6 SPILI_CO\TROL..................................................................................................................................................................6 V. CONVEYANCE SYSTEM AVALYSIS.4ND DESIGN...................................................................................8 S r,arv��aR�Rtclt!ik[:n�t:n rs(B�si:n c�v KCSVI�'DM;wu S.AO):......................................................................................8 OV-SI iF COVVEY.AVCG......................................................................................................................................................8 VI. SPECIAL REPORTS AND STUDIES.............................................................................................................. 10 �'ll. OTHER PERNIITS............................................................................................................................................... 11 Vlll. CSWPPP ANALYSIS AhD DESIGN............................................................................................................ 12 Sl;1NU;\RD REQCIRES1I:?�TS............................................................................................................................................. I? IX. BOND QUANTITY', FACILITY SU!�1'�1ARIES,AND DECLARATION OF CO�'ENAIYT................... 13 X. OPERATION AND MAINTENANCE :VIANUAL.......................................................................................... 14 ST:1\[):1RD M.�IN I I:�AhCE.............................................................................................................................................. 1=� COUGHLINPORTERLUNDEEN [�rntcm�9emorial Stadium 1 King Counh��ti'ashington LisT oF�cuaEs Figure 1 -TIR Worksheet-Secdon 1 Figure 2-Site Location-Section 1 Figure 3-Drainage Basins,Sub-basins,and Site Characteristics-Section 1 Figure 4-Drainage Basin-Section 1 Figure 5-Floodplain/floodway FEMA I��'Iap-Section 3 Figure 6-SCS Soil Survey-Section 1 and Section 3 Figure 7-Sensitive Areas Map-Section 3 LIST OF TABLES Table 1 -Existing Site Conditions Area Breakdo�vn....................................................................................................5 Table?-Developed Site Conditions Area Breakdown...............................................................................................5 COUGHLINPORTERWNDEEN Renton�Iemorial Sta��ium lI hin�;Cc�unt�'1ti'a�hingh�n I.PROJECT OVERVIEW General Description The following Technical Information Report('ITR)provides the technical infarmation and design analysis required for developing the Drainage and Temporary Erosion and Sedimentation Control Plan(TESC)for Renton Memorial Stadium. The stormwater design for the project was based on the requirements set farth in the 2009 King County Surface tiNater Design A�anual(KCS�ti'DM)(See Figure 1 - TecltrticaI Infvrntntiori Rc��ort�1lorkslieet)and the City of Renton Amendments to the 2009 KCS4VDM. Renton Memorial Stadium is located within the Ciry of Renton,located at 405 Logan Ave N(See Figure 2- Site Location). The site is in Section 07,Township 23 North,Kange 5 East,�h'illamette Meridian. The area to be redeveloped is approximatel�2S acres of an existing 14.�acre site.The existing site consists of 11.28-acre impervious area and 3.76-acre pervious area;while the proposed conditions�vill consist of 11.25-acre impervious and 319-acre pervious.The site currentl}'has a priman�stadium and courtyard, south parking lot,rubUerized track and astroturf field,north grandstands and bathrooms,and north parking lot.Soils for the area were mapped using the King County Soil Survey maps(See Figure 6-SCS Soil S1.tm��). The proposed project consists of a ne�v north ticket booth,bathrooms,and vie�ti ing area. The existing stadium will also be renovated. Associated site improvements include replacing the existing stadiums asphalt courtyard with concrete paving along with removing the existing north bathroom and ticket booth. An existing private parking lot to the east of the stadium will be reconfigured and part of the asphalt��-i11 be removed to create a landscape buffer next to Logan Ave. The total impervious area in the developed site �vill be less than the current conditions. The primary storm drainage for the site�vill not be disturbed. Roof drainage off the north buildings�vill drain to existing conveyance systems on site. Ne�v fire services will be installed to serve the ne�v north Uuilding and the existing stadium. Sewer will be extended to the new north building and portions of the side sewers serving d�e stadium will be replaced. Existing Conditions The existing site has a large parking lot that takes up the entire south half of the site. The northern half of the site has a rubber track and astroturf field. A stadium sits along the south side of the track and Uleachers sit along the north side. A small parking lot occupies the northeastern corner of the site. Runoff from the track,bleachers and small parking lot a�l discharges to a 12-inch pipe that discharges to the Cedar River just west of the track. The stadium and south parking lot discharge to a?�-inch pipe that discharges to the Cedar River just west of the south parking lot. (See Section 4,Figure 3-Drairrc�gc Bnsiris, St�b-basiris,an��Site Clinrncteristics). No downstream analysis�ti�as preformed because the site discharges directly to the Cedar River.(See Section III). Proposed Drainage System The exisring drainage system onsite will not Ue disturUed during the site improvements. Runoff from new and existing buildings will be connected back to existing drainage structures. Both direct discharge points to the Cedar River will remain the same. No new pollution generating surfaces will be added to the site; therefore no�vater quality mitigation��ill be installed as part of this project. The site has direct discharge to the Cedar River,therefore under the 2009 KCS�ti'D'�-'I the site is exempt from providing detention. (See Figure 3-Drainage Brtsiras,Sa�b-br�sins, an��Site Clu�rncteristics). COUGHLINPORTERLUNDEEN Renton n4emorial Stadium 1 King Countt'61'ashington KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WQRKSHEET Part 1 PROJECT OWNER AND Part 2 PROJECT LOCATION AND PROJECT ENGINEER DESCRIPTION Project Owner ��N r orJ S�Noo�. p15TR.ic.� Project Name 1ZEr�f7oN ME(�lolza.4 — ,u� Phone �`'(LJ� Zoy - Z3oo DDES Permit# 1`E/Pt Address '�p0 5W "7�"' �T Location Township 23 hf Qen+on W 4 9 8��7 Range 5� Project Engineer 5 EA f�l zoBtr�z>aa� PE Section O� Company Covo,l�i,,� {"��r-�-e+r /�und.a.2r� Site Address `�o S �.o�q.N l�VE N Phone ZOb `{3- o b� �+ti-�ov� Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS ❑ Landuse Services ❑ DFW NPA ❑ Shoreline Subdivison / Short Subd. ! UPD Nlanagement ❑ COE 404 ❑ Building Services ❑ Structural ❑ DOE Dam Safety M/F I Commerical / SFR RockeryNault/ Clearing and Grading � FEMA Floodplain � ESA Section 7 ❑ Right-of-Way Use ❑ COE Wetlands ❑ Other ; ❑ Other I Part 5 PLAN AND REPORT INFORMATION I Technical Information Report Site tmprovement Ptan (Engr. Plans) ' Type of Drainage Review Ful / Targeted / Type (circle one}: Fu I Modified I (circle): arge Site Small Site Date (include revision Date (include revision dates): dates): i Date of Final: Date of Final: � Part6 ADJUSTMENTAPPROVALS Type (circle one): Standar ! Complex / Preapplication / Experimental! Blanket Description: (include conditions in TIR Section 2) i Date of A roval: 2009 Surface Water Design Manual lr'9/2009 1 � �ING COL�NTY, �VASH1�iG"IOti, SliRFAC� �`ATER DFSIG\ ,��I_ANli.�.L TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REQUfREMENTS Monitoring Required: Yes No Describe: Start Date: Completion Date: Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : N f f� Special Distnct Overlays: 1-�ff�- Drainage Basin: 1—ac.�c'-(Z- C��' 4 v�2 Stormwater Requirements: .Lr�Go�po�L1-T�D �lt R-�Pt� I Z_ - Part 9 ONSITE AND ADJACENT SENSITIVE AREAS ❑ River/Stream ❑ Steep Slope ❑ Lake ❑ Erosion Hazard ❑ Wetlands ❑ Landsiide Hazard ❑ Closed Depression ❑ Coal Mine Hazard �Floodplain C.��(Z (Z(V�2 ❑ Seismic Hazard ❑ Other ❑ Habitat Protection ❑ Part 10 SOILS Soil Type Slopes Erosion Potential i U r L�►�—t-1 �--2°�., ��c..� I ❑ High Groundwater Table (within 5 feet) ❑ Sole Source Aquifer ❑ Other ❑ SeepslSprings ❑ Additional Sheets Attached I 2009 Surface WaterDesign�lanual 1i9i2009 2 _i - I KING COUNTY, WASHII�rGTON, SURFACE WATER DESIGN MANtiAL !� TECHNICAL INFORMATION REPORT (TIR) WORKSHEET � Part 11 DRAINAGE DESIGN LIMITATIONS - REFERENCE LIMITATION/SITE CONSTRAINT ❑ Core 2—Offsite Analvsis ❑ SensitivelCritical Areas ❑ SEPA ❑ Other ❑ ❑ Additional Sheets Attached Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) Threshoid Discharge Area: name or descri tion Core Requirements(all 8 apply) Dischar e at Natural Location Number of Natural Dischar e Locations: Offsite Analysis �� Level_ 1 ! 2 ! 3 dated: Flow Control Level: 1 / 2 ! 3 or Exemption Number incl. facilit summa sheet ��A Small Site BMPs Conveyance System Y ,�q Spill containment focated at: ��, Erosion and Sediment Control ESC Site Supervisor: —(j�� Contact Phone: -�$p After Hours Phone: � Maintenance and Operation Responsibility: riva / Public If Private, Maintenance Lo Required: Yes / o Financial Guarantees and Provided: e No Liabili Water Quality Type: Basic I Sens. Lake I Enhanced Basicm / Bog (include facility summary sheet)t�� or Exemption No. f Landsca e Mana ement Plan: Yes / No S ecial Requirements as a pticable Area Specific Drainage Type: CDA/SDO/MDP/BP/LMP!Shared Fac. !None Re uirements �l� Name: Floodplain/Floodway Delineation Type: �la�' / Minor ! Exemp#ion / None 100-year Base Flood Elevation (or range): �t1= Datum: N �J l °o� Flood Protection Facilities Describe: Exc s t�Nt, ��EF - Source Control / Describe landuse: (comm.findustrial landuse) N }� Describe any structural controls: 2009 Surface Water Design Manual 1/9/2009 3 KING COUNI�Y, W,ASHINGTON, SliRFACE WATER DESIGN 1�1,aI�UAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET ^ Oil Confrol High-use Site: Yes / o Treatment BMP: Maintenance Agreement: Yes / with whom? Other Draina e Structures Describe: �� f Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION �Clearing Limits �Stabilize Exposed Surfaces �Cover Measures �Remove and Restore Temporary ESC Facilities �Perimeter Protection � Clean and Remove All Silt and Debris, Ensure ❑ Traffic Area Stabilization Operation of Permanent Facilities ❑ Sediment Retention �Flag Limits of SAO and open space preservation areas ❑ Surface Water Collection ❑ Other ❑ Dewatering Control �Dust Control ❑ Flow Control Part 14 STORMWATER FACILITY DESCRIPTIONS Note: Include Facili Summa and Sketch) Flow Control T pe/Description Water Quali T e/Descri tion ❑ Detention � ❑ Biofiltration � � ��-� � ❑ Infiltration ❑ Wetpool ❑ Regional Facility ❑ Media Filtration '' ❑ Shared Faciliry ❑ Oil Control ❑ Flow Control ❑ Spill Control BMPs ; ; i ❑ Flow Control BMPs ! ❑ Other i ❑ Other i 2009 Surface Water Design A4anual 1/9,i2009 4 KING C011'�ITY, WASHINGTOti, SURFACE ��'�TER DESIG�I '.VIANUAL TECHNICAL INFORMATION REPORT (TlR) WORKSHEET � Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS ❑ Drainage Easement , )'� ❑ Cast in Piace Vault ❑ Covenant l ❑ Retaining Wall , 1/ /ti ❑ Native Growth Protection Covenant ❑ Rockery>4' High (`-� t� ❑ Tract ❑ Structural on Steep Slope ❑ Other ❑ Other Part 17 SfGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my knowledge the information provided here is accurate. , s-�.� ��s�— � f I � � , ,� ' Si ned/Dats I � I 2009 Surface Water Design Manual 1/9/2009 5 � I FIGURE 2—SiTE LOCATION �r ��.�-� � —�-�.*•...�.... , ��- ,��-� � - - .. _. �, �, p F,,., . �� i � � ,.., •. '`�� '.'�y � _ Y. ��y 1 .'.! e,� • .��'� I � t `� � � '1 'p'� [ � ;y � • y ; ��' �t(� �'� * ��–�:; �� .�' ' �' � r y • !�,I � ^ ,, •„ •17 ,_ R i N ' ,+i •� , � ____ , + r � . .� � , •, - f � ..�. � I� .' � � . ' r...__ _..;� � "'� , ,. . .. � � I ` � ' I ' . µ � ` �` ' . `�..,..._ _."_,�'' �� '�� ,� ;-'�,I: 'l� "�� , ' ` b "`,,r �1 � ,, � '� ' � , ,* w � � r� ; s" k. , -a�,� � .� i' ,� �t � . , ��.,�«-_• ,�.�} � ,; # :,� �,�� .� ,• :��,�' +". � --' l - •r � � � , � � . ;,� _y,f ,_� ,� ;� -- � 11'�\ `•I 1�'�� 1�! (r .. . � ��.�. • •1�� `n 1. ,�.� l. !C� � R��1 1� � �i . 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'�.." � '�I �f1 +�;�. i .� •.��+.; •t r • �b• %1 .,�� ie9�• , � �� i� �• ,r ,.�,, _, -�-�1 �-,.• ._ , - �'� � ' ��,/ ,L' � '' �� ,S ,\ � � ' . ,1� r , L:, i .�' 'f�i-.'I I-it"1�, 4'I qsi' �.--�� nL,.,� ' ' � -�� - COUGHLINPORTERLUNDEEN Rcnton Memorial Stadium Kut�Cow� �Washu� ton FIGURE 3 -DRAINAGE BASINS,SUB-BASINS, AND SITE CHARACTERISTICS I .� � ' , . .�... � '� �' �F•� � � � � i * N _�.. 1 �" � �' j� � � ,�� '� _ � „ o � �� i'�' � ilal�� " '�• � � ';.,, .� . . '�.• �. � ' t . # a`„ • ' � ti North Discharge � � �� ' ' l� ' � = Point(12" Pipe) - '� : 1 � • � � _ i ► _ �/�� '� ■• . -� ■ ■ 1-" �.r t� ,r.�,„ �; � �- , � •. �`M `' � C �� #� � ' R' .�! e�� 'b y.1 � � .a�� ' �[�� I �, �, � ," � ` "' 1, �, � � � : } . � r ,< �� , � _ �'� '� � ,� �; . , ��. � �,, . _�:� �..�, a , � �e '� �;' "�F` � � �y��' - � i. .. ' 3i•.� ��i + � � � � � , ! �. ,.► �1 ,,�� ar �� - � .__._. .�. ,�� : , ,: ��°�y •+ . �,` = c i� . : �" � , �� , � � � * , t,� ��a� �r;ar�.=a�- :.r.',,;i _� . ,� �, '�. 1�r � ,*, � i ., - « -�� ' � �' .!' '' . ---. � ' t t''� �,�'� "�. srt�' �`� � � �� - r ��,� � .� , . , ' � l � �� •� � . � 7,.-R �, a . ��, .,� � ,�'` �� a y ` f .r�r '�� m �- - • � ,�� ± �� . ;�,�'�, �-:.�+P"�'a� �� . � . , � �t . �.�.�.. , «� . i_ '-�� j� ' � , , � � '' �: � ' �'+ ' 1� � � •�--�� ' �. . , . � � � '.�_l.'. y�� . �� : '� �c �� y�� `� 1. t SouthDischarge .� t' � , ��,. Point(24" Pipe) � �. ,' � -�1. � i. „ ` ., '�.. � '� ; . . '�%'' ��'� '� 3 � ' x� � Tr ,�r I North Basin COUGHLINPORTERLUNDEEN Penton h4emorial Stadium King Counh��h'ashingtnn FIGURE� — DRAINAGE BASIN -,- � — „— :-r. — .5}„ ; ��.. ; ,.�. . ��".:�,F i , . .-.:. � � r 4 . - � , n ' - " - _ � ��' � r_: � ,,_ ; - -._. �°� N ? �•y :r f. .� � �'' �._ - �* `� . J,s -- --,,_ y "" - z� .,� .- `�,, _ l, - N , - � �� ,,, � ,' .= .� ,�. _ � �.-. ,v�1 �-J �.CI��eC �A 11 i . [.M�ud t Cedar River � - - � B�sin . �I '� . 1� �.`,�. � ; ,-,_ :_ �) .r, • ` E �� „ �j . � I � " %��ti_,� l� �� ,: ; � . �.� �� ` _ ;, , . ,�^ .� __,. �, - � _ �' � = ��.. �, �� 4 � - = ; ,Y;;_ '� ytr F t .•t.l' .1 i• ..r� '' '� .C- . �f �. .. ~y' � v , ��-�� y ��''� - �� ' �� -tr ts �I� '; , �� _ - � " �T' —__ ` ' � I � �' �, - 1, •� � 6 . , q 1 �' ..� � ri - f r _ : -� `t � '_i ., . '�� ' ` � �- . 1j,' y � •��5�_ � `. . �� t � � �'Y' S �-~�� 5.� - �.t'�'l* .� i. _ _ = � -�, ,�' r - -'�t.� `'�_ _ - _ - i� - ',•_ _ ) � ,�.1_ � �-s, :� t _ , _'� - '.�c.�y-�y , �'i� �� _ . ��t ; �; M' _�ati S /- � . �: � � •�'; T � '�:�'-'ti ` 4; .i S� . ' � `k • � � M 1. f�^ , r�}�� "�"� : ��} r1. r - Vf ry . I ._1_.' .� C�".i .�r 1 i `" :�, ��-' - ' � '��4 :�e _ �' . . ,,1� /r tf�� •• � ��. �� a � "-+R� "I � � I 'ta„ r � �. �� - J •,,;r, -- �t \ I • I ; �� _� � y _ � ,7�' ''�i1 p:�"r I vf za ; , '��,�j sr ' � ----�.- , �j ,i j ..s. � .�. • 4 �' . `T �, �� iL`� �tl �V � �,� 4� � �`• �I � , �� t- .? r L�__ C.� ��; rr.rz..r,, , ._ .. . - , - - �� - . li s i , `'� � k - �` I Basin Locations o 05 , ��'�� o�� —� SurEace Water UGlay =--= j Camprehensive Plan �—�� PnnBed 1d1812009 �_- �� City o1 � `:_-� C in.K a�r�avu �� r� r ��► �� .�°� �� COUGHLINPORTERLUNDEEN Rentan hfemorial5tadium King Counn•6Vashingt�n � II. CONDITIONS AND REQUIREMENTS SUMMARY - This section�vill address the requirements set forth b�° the C�re and Special Reyuireil�ents listc�d in Chapter '- 1 of the KCSVVDII. King County Surface 4�'ater lianagement Design I�ianual Core Requirements: l. Discharge at the Nc�tural Location(1.2.1):All developed flrn��s��°ill l��c��nve��r�i to th��istin�; discharge points west of the proposed improvements. 2. Off-site Analysis(1.2.2): Refer to Sections III and�'. A Ltvel 1 do��nstream anal�sis has not l��en performed because the site discharges directly to the Cedar River. 3. Flozu Co�itrol(1.2.3):Refer to Section IV.The site has direct discharge to the Cedar River and is exem}�t , from providing detention. See page 1-37 of the KCSWDI�1,taUle 1.2.3.B. That table states that the lo��<�� Cedar River is considered a major receiving water and direct discharge exemption aE,E,lirti tc>thi5 tiitr. 4. Conveyanee S�stem(1.2.4): Refer to Section V. Clc,se�i E�iF�e s��t��s an�i <<�n��r��anc��hann��l� h��e been provided for on-site stormwater conveyanc��. 5. Erosiori arid Sediarterrtation Corttrol(1.2.5):Refer tu�ertiun 1�. l�he pr�,j��rt ��ill <<�n�tru��t �j ��it�� f sediment controls to address the specific conditions at the site. 6. �'TLitiltCllRttCCRiIL��JQi'RtlOt1S�1.2.6�: R2f2it��c'if1i�I1 �� l�lt' ('I�i��i��,? �� ,��•,, .!� 1�,,.'�� ` .�: i"� �.. � owned,operated and maintained b}'the oti n 7. FinarieialGuarariteesa�idLiabrlit��(1.2.7): I ��.� .��,�. �,�� .� ,� ��,��,�. .�� ,. ��; , ��: � �� , ��.,, , F ,; ,�t� pI'101� �� t�lt' �il't'Illlllll�' ��} :��II�tI�U��fl��ll i�li' i}�I��J�'�t� Il�fllli �� '1� Ili'� �� I�� `i' Ic��'��;l�l�`�i' !��I I��i�Ull�i�i� bond� 8. Wate��u�tlitJ(1.?�5): IZcter t�>>c�tiun 1�.L. 1��it��r��ualit� trcatn�t�nt�s n��t r� �� development because n�pollution generatin�surfaces are being added or r� Special Requirements: 5�72CIdIR2C�U1TeITl211t#1. L�[Il�'f :1�1��%i�'�1 :11��'d-�}��'�Ill� h��iiil��ill�Ill��'�UUIi 1..� • Gitical Drainage Areas(CDAs):Not ApplicaUle • Master Drainage Plans(MDPs):There are no kno�vn master drainage pl�, � , site. • Basin Plans(BPs):The project is located�vid�in the Cedar River Basin Plan. • Lake Management Plans(LI�-1Ps):Not Applicable • Shared Facilih�Drainage Plans(SFDPs):Not Applicable Special Requirement#2. Flood Hazard Area Delineation,Section 1.3.2: See Figure 5 for 100-yr flood zone. No work affecting the flood storage�n-ill take place within the 100-yr flood zone. Special Requirement#3. Flood Protection Facilities,Section 1.3.3:Not Applicable Special Requirement#4. Source Controls,Section 1.3�: See attached Activity Worksheet and Required BMI''s. Special Requirement#5. Oil ControL•I�-linimal traffic is anticipated in this area. No oil control is required. Project Specific Requirements: COUGHLINPORTERLUNDEEN Renton'�lemorial Stadium 2 King Count��6b'ashingtan I-here are no additional reyuirements for this portion of the pmject. Design and cc�nstructi�n will abide b� requirements set forth in these documents and King Count��. COUGHLINPORTERLUNDEEN Rrnh�n Alem�n��al Sta�iium � Kin�;Cnunh 1�'ashinf;t�m �-_ I �. Name: Renton Memorial Stadium ', BusilleSs T e: Athletic Facility Address: 405 Logan Ave N, Renton Wa Activity Use this worksheet to identify the activities that you conduct. Do you conduct this Sheet Interpret the categories broadly. Numbers A-1 —A-43 activity? If so, Number correspond to sheets located in Chapter III. where? TYPE OF ACTIVITY INDOORS ouT�ooRs A-1 Re uired BMPs for All Commercial Pro erties X X A-2 Storage of Liquid Materials in Stationary Tanks This does not include under round tanks or small containers A-3 Storage of Any Liquid Materials in Portable Containers Such as drums, buckets, 'u s, or barrels A-4 Storage of Soil, Sand, and Other Erodible Materials - This includes stora e of all t es of erodible materials --- A-5 Storage of Pesticides and Fertilizers ._ This includes non-li uid esticides and ba s or iles of fertilizer _ A-6 Storage and Treatment of Contaminated Soils This a lies to contaminated soils that are excavated and left on site A-7 Storage and Processing of Food Items This includes storage of fruits, vegetables, meats, and other foods and processing activities at wineries,fresh and frozen juice makers, and other food and bevera e processin o erations A-8 Storage of Solid Wastes and Food Wastes (Including Cooking Grease) X X This includes re ular arba e and all other discarded non-li uid items A-9 Storage of Scrap and Recycling Materials (Including Auto Recycling Facilities) This includes scrapped equipment, metal, empty metal drums,junk appliances and vehicles. and assorted rec clables A-10 Treatment, Stora e, or Dis osal of Dan erous Wastes A-11 Cleaning or Washing of Tools and Equipment ' This includes tools, all types of manufactured equipment components, and - work e ui ment such as lawn mowers and fork lifts A-12 Cleaning or Washing of Cooking Equipment This includes vents,filters, ots and ans, rills, and related items A-13 Vehicle Washing and Steam Cleaning This covers cleaning and washing at all types of establishments, including fleet vehicle ards. car dealershi s,car washes, and maintenance facilities A-14 Interior Washing Operations (Including Mobile Contractors) This includes car et cleaners, u holste cleaners, and dra e cleaners A-15 Pressure Washing of Buildings, Rooftops, and Other Large Ob'ects A-16 Truck or Rail Loadin and Unloadin of Li uid Materials A-17 Fueling Operations This includes gas stations, mobile fuel trucks, pumps at fleet vehicle yards or shops, and other rivatel owned um s A-18 Engine Repair and Maintenance This covers oil chan es and other handlin of en ine fluids A-19 Concrete and As ha�t Production at Stationa Sites Activity Use this worksheet to identify the activities that you conduct. Do you conduct this Sheet Interpret the categories broadly. Numbers A-1 —A-43 activity? If so, Number correspond to sheets located in Chapter III. where? TYPE OF ACTIVITY INDOORS ouT�ooRs A-20 Concrete and Asphalt at Temporary Sites This includes construction sites, remodeling, and driveway and parking lot X X resurfacin A-21 Manufacturing and Post-Processing of Metal Products This includes machining,grinding, soldering, cutting, welding,quenching, rinsin , etc. A-22 Painting, Finishing, and Coating of Vehicles, Products, and E ui ment A-23 Wood Treatment and Preserving This includes small scale contractor operations(such as patio decks)and lar e scale lumber treatment o erations A-24 Commercial Com ostin A-25 Chemical Applications-Other than for Landscaping This includes use of al aecides,fun icides, pesticides. and rodenticides A-26 Landscaping Activities ! � This includes vegetation removal. herbicide and insecticide application. , X ' fertilizer application, ardenin . and lawn care ' A-27 Clearing, Grading, and Preparation of Land for Small � Construction Pro'ects A-28 Demolition of Buildin s X A-29 Buildin Re air, Remodelin , and Construction X A-30 Boat Buildin . Maintenance, and Re air A-31 Vehicle and Equipment Parking and Storage This includes all types of parking lots(commercial, public. and private), retail/store parking, car dealerships, rental car lots, other fleet vehicle lots, e uipment stora e and arkin areas such as at e ui ment rental ards A-32 Sidewalk Maintenance This includes cleanin and deicin A-33 Swimming Pool and Spa Cleaning and Maintenance This includes all swimmin pools and spas not at a sin le famil residence A-34 Keeping Animals in Controlled Areas This includes kennels, rabbit hutches, and similar animal rearin and care A-35 Keeping Livestock in Stables, Pens, Pastures or Fields This includes cattle, horses, pi s,sheep, oats. and other hoofed animals A-36 Logging and Log Yards This applies to Class IV eneral forest ractices onl A-37 Mining and Quarrying of Sand, Gravel, and Other Materials This covers sand, gravel, minerals, peat, clay, rock, etc. but does not include excavation at construction sites A-38 Well and Geotechnical Drilling This includes mechanical drilling and directional drilling for water wells and utilities, environmental protection and monitoring wells, and geotechnical borin s A-39 Roof Vents and Fu itive Emissions Includin Dust A-40 Street Deicing Operations This includes deicin and anti-icin of streets and hi hwa s A-41 Wheel Wash and Tire Bath O erations A-42 Potable Water Line Flushin or Tank Maintenance A-43 Use of Soil Amendments on Construction Sites � King County Stormwater Pollution Prevention I�� Manual Best Management Practices for Commercial, Multi-Family and Residential Properties January 2009 I Prepared by: King County Department of Natural Resources and Parks Water and Land Resources Division � Stonnwater Sen�ices Section Required BMPs fol- All Cominel•cial Pl•oper-ties � The following B1�IPs are required if you o�vn or occup�� commercial, industrial, agricultural, public, or multifamily residential property in unincorporated King Count,y. Clean Your Storm Drainage System Maintain your storm drainage system by removing sediment and other debris to prevent the transport of pollutants into receiving waters. The storm drainage system includes all drains, catch basins, pipes, ditches, gutters, and flow control and ��-ater quality facilities. � See BMP Info Slleet 7 irl Chapter � for details on drainage syste�n maintenance. Eliminate Illicit Connections to the Storm Drainage System A common situation that can cause severe stormwater pollution probleins is discharge of non-stormwater to the storm drainage system. Examples are discharges froin internal floor drains, appliances, industrial processes, sinks, and toilets. These are sometimes illegally or inadvertently connected or drained to the nearby storm drainage system. These discharges must go to the sanitary sewer system, a holding tank. an on-site process water treatment system, or a septic system. You mu� correct these illicit discharges. If you have any questions as to ��hetl� _ your discharge is allowable, contact :'.� �;��.�� ;-�.��__��_. `��:�,;,� _�.,��_l I .�n�_i PC�t�IICCC� 1)]�'1>l��Il [if �O(�-��)(i-lOflll, _ �' �See B1��1P Ii�o Sheet 1 in Chapter � for infomlation on hu�� t� check for illicit connections. You can also ask for help from your local sewer utility. If you find out that your inteinal drains are January 2009 King County Stormwater Pollution Prevention Manual � Requrred BMPs for A!!Commer�ial Properties(continued) improperly connected to the storm drainage system, they vvill need to be either removed,permanently plugged, or connected to the sanitary sewer, septic system, on-site treatment system, or a holding tank. Stencil Your Storm Drains Stencil or apply storm drain markers adjacent to storm drains to help prevent the improper disposal of pollutants. Storm drain inlets should have messages such as "Dump No Waste - Drains to Stream" applied next to the catch basin to warn against the intentional dumping or discharge of pollutants. If the metal catch basin grate has been cast with this message, marking the drains is still recommended, but may not be required unless evidence is found that pollutants are being dumped or washed to the storm drains. For more information or assistance in implementing these best management practices,contact the King County Department of Natural Resources and Parks Water and Land Resources Division at 206-296-1900. ' Reader Note: The above requirements are the minimum required BMPs. If these BMPs fail to prevent dischar�es to the storm drainage system,you will be asked to take additional measures to correct the continued pollution discharges. King County Stormwater Polfution Preventron Manua! January 2009 Storage of Solid VVaste and Food Wastes (Including Cooking Grease) This acti��ity applies t� }�ou if}`ou st��re solid ��-astes includiii� both food and noil-food ��aste, outdoors. This typically refers to garbage dumpsters, other outdoor waste containers such as cooking grease barrels or containers, and any stockpiled garbage. Improper storage of non-f�c�ocl solid wastes can allow toxic compounds, oils and greases, metals, nutrients, and suspended �olids to enter stormwater runoff. Stormwater runoff from food waste storage areas may be contaminated with oils and greases, nutrients, and suspended solids if waste containers ai�� leaking, are not covered, or are too small to contain the amount of��:aste generated. If�-ou �t�>r� dangerous wastes you must follo«� specific regulations outlined bv the VVashington Stat� Department of Ecolo�� . � The follo��-ing BMPs, or equivalent measw�es, methods, or practi�F�>; �re rec�uir•ed �f��u are �ngaged in �toraae of so�id ��stes or fa�,__ `t1iel�Lo, .� >' ��_i�'�Il � ,� I�]'�. ___�_ _Il; ` `i`�'1,!' l�. !ll_��I �_ ��r '��:��1_ � .� : t solid lids.\Keep dumpsters closed�except when adding waste. If��a��t is not in containers, co�.�er alI waste piles (plastic tarps are acceptabl� coverage) and prevent stormwater run-on and run-off with a berm cr similar method. Keep all ��aste piles covered except �vhen in use. � See BMP Info Sheet 5 in Chapter � for information on contaiiuilen: and run-on prevention and Rl�1P Inf� Sheet � for information on covering options. ��'hen transferring cooking oil;`grease to outside containers ti-o;�1 kitchens, eover the container with a tight lid during transport and cle�:r up any spills immediately. Keep the area around the grease containe clean, free of erease. and debris free. Use drit �., , �_}-�� t,�.- ��_� � I� .. 1._�� __� _ _ �i�� . �.�. _ . _ C'111�-�tlt'U ��'�� ,tC�._::1; �CG�1�� i��i llli'. � . :11L'�11_':�. �:._..�� i]�_'�� l� _�� _ �'_ �'�.l_t . ��,.- _,.�'� �`; �_� _.., � ,, .. r . '�� ..,, r _�iC1. c`3l' ,G�l __ _ _ — Storage or Solid Waste and Food Wastes(Including Cooking Grease) (continued) ground. Clean up spills iminediately. Collected grease must be properly disposed of as garbage. Required Routine Maintenance: • Check storage containers as needed for leaks and to ensure that lids are on tightly. Replace containers that are leaking, corroded, or otherwise deteriorating. ' • Sweep and clean the storage area as needed if it is paved. Do not hose down the area to a storm drain. • Dispose of rinse and v�Tash water from cleaning your containers into a sanitary sewer according to health department requirements, or if no sewer is available, store in a holding tank, dead end sump or truck off site to an approved disposal location. � See BMP Info Sheet 2 in Chapter 5 for information on disposal ', options. ' For more information or assistance in implementing these best manajement practices,contact the Kin�County Department of Natural Resources and Parks Water and Land Resources Division at 206-296-1900. , Reader Note: The above requirements are the minimum required BMPs. If these BMPs fail to prevent discharges to ' the storm drainage system, you will be asked to take additional measures to correct the continued pollution discharges. King County Stormwater Po!lutron Prevention Manual January 2009 I I� Concrete and Asphalt Application at Temporary Sites This activit}� applies if you apply asphalt and/or pour concrete for building construction, road construction, sidewalk, curb and gutter repairs and construction, sealing of driveways and roofs, and other applications. These activities are typically done on a temporary site-to-site basis where permanent BMP measures do not apply. Asphalt application can contribute high concentrations of toxic hydrocarbons, other toxic organic compounds, oils and greases, and metals to stormwater runoff. Concrete pouring can contribute suspended solids and metals to ston�l�i ater runoff and cause detrimental pH changes in receivin`� �a at�r�. � 1�he following BMPs, or equivalenF En��.+��►��. i:�c::�c�ci,, c;,� ��r�,: � are required if you are engaged in concrete pouring and asphaf� application at temporary sites: L se drip pans, ground cloths, hea�ry cardboard or ply��ood wherever concrete, asphalt, and asphalt emulsion chunks and drips are likely to fall unintentionally, such as beneath extraction points from mixing equipment. , Provide storm drain covers, inlet protection or similarly effective containment devices over all nearby drains at the beginnin� of t} , ��orkday. All accumulations of runoff aggregate chunks, and otl solids must be collected for proper disposal at the end of the wor��._. (or more frequently) prior to removing the containlnent nr cover device(s). Drain covers and other c�ntainment device� the top layer of unhardened concrete is hosed or scraped off to leave ai exposed aggregate or rough finish. Never wash or allow the discharge � concrete slurry to a storm drain, ditch, roadway shoulder or gutter. Use . storni drain cover, inlet protection or other containment device, such a� a hand-dug sump ��here slurry can be directed to and contained. (Se�� item 4 hclo��). .All collected nmoff must he properl� disposed ot. Jdr�uary 2GG9 Kiny County Sionn�:�ater Pollution Preventron iNarival Concrete and Aspiralf Application at Temporary Sites(continued) Concrete and concrete pumping vehicles shall not discharge any concrete, slurry, or rinse water into street gutters, storm drains, or drainage ditches or onto the paved surface of a roadway or drive�vay. Designate a wash-out area onsite where application and mixing equipment cleaning wrill be conducted. This ��vashout area can also be used as an area for rinse water control. It is also acceptable to dispose of rinse ��ater and slurry in a hole in the ground large enough to contain the slurry and rinse material. Commercial products and services are also available for concrete, slurry, and rinse water containment and disposal. Routine Maintenance: Sweep the pouring area at the end of each day or more frequently if needed. Collect loose aggregate chunks and dust. Do not hose dov��n the area to a storm drain. � . . . The follo��in� B�7Ps are optional, unless the abo�-e minin�;�� s�c��aE.��-��3 t3�11', �lr� rri�t ,��-u;�i�E� ;�:{4��E��?c� ��.:E-cr c��ntr�i�: � , �'�; ..i��`��. �i��'...��I� , i`� .'_�l Illl`.li'_ � '_I':�Ill�'Ii��. il��il��j i��_ �� 1��! �"�A ,iil awnin�r ��r ��th�r ;impl� �ti�tictur� ��hil� �ai�lin�� t�� a��i�i cc�nta�t «�itil rainfall. A catch basin insert configured for sediment removal ma�� r�m�� ome of the pollutants in runoff from this activity. This is especially useful if the activity must proceed on rainy days. Catch basin inserts require frequent maintenance to be effective, so consider this when evaluating your options. Concrete work of all types tends to cause elevated pH in runoff, and it must be monitored and neutralized before off site discharge of the runoff occurs. � See BMP Info Sheet 10 in Chapter 4 for more information. For more information or assistance in implementing these best management practices, contact the King County Department ofNatural Resources and Parks Stormwater Services Section at 206-296-1900. Reader Note: The above requirements are the minimum required B�IPs. If these BMPs fail to prevent discharges to the storm drainage system,you will be asked to tal:e additional measures to correct the continued pollution discharges. King County Stormwater Pollution Prevention Manual January 2009 Landscaping Activities and Vegetation Management This broad activity encompasses all aspects of landscaping and vegetation management, from small- scale yard maintenance to large-scale commercial landscaping businesses and vegetation management programs. It includes vegetation removal, herbicide and insecticide application, fertilizer appiication, watering, and other gardening and lavvn care practices. Stormwater runoff from areas that have been subject to pesticide or fertilizer application or extensive clearing, grading or cutting may be contaminated with pesticides and other toxic organic compounds, metals, oils, �u�nended ��lide. n!�tricnt; fr�m fc�-tili�er_ and cnlif��rni ractcri,�. and m�� ca>>se hi�chemical n�� lYM is an approach that uses an array of inethods to manage pest damage with the least possible hazard to people and the environment. IPM uses a combination of biological, cultural, and physir. practices that can significantly reduce or eliminate the use of pesticides. See Activity Sheets A-5, "Storage of Pesticides and Fertilizers" and A-3, "Storage of Liquid :�-9aterials in Portable Containers." Landscaping activities related to golf courses should refer to King County's Golf Course BMP Manual (see Chapter 6 of this manual for more information). ,�'ote: Tlie �er•n�pe.c�icide if�clzrdes ir�secticides, 1�erbicides,fi�ngicides, rodenticides, etc. e "The following BMPs, or equivalent measures, methods, a are required if you are engaged in landscaping activities: Do not ap�l�� an�� pesticides directiv to surface ��aters. unle�� applicatioi of Ecolog.. Mix pesticides so that spilled material ��ill not bc ��ti�ashed to sur�. the stonn drainage system, or onto the ground. Clean up any spills immediately. Ensure employees are trained on the proper use of pesticides and in pesticide application techniques to prevent pollution. Washington pesticide la�v requires most businesses that commercially apply pesticides to the property of another to be licensed as a Commercial Applicator. Follow manufacturers' recommendations and label directions. Pesticides and fertilizers must never be applied if it is raining or about to rain. Do not apply pesticides within 100 feet of surface waters such as lakes, ponds, ��etlands, and streams. This also can include storm��ater conveyance ditches. Remove weeds/vegetation in stormwater ditches by hand or other LSndscapingActivities end Vayet�hon Man�y�inent �contir�uedl mech�3nical means. C�h�mirals 5houid h� us�d �2s a last res��rt. . Disp��se c�i'��rass clippin��s. leave�, branche�. ;ticks, ��E� <�th�r c��llected vegetation, by recycling, composting, or burning (if allo��ed). Do not dispose of collected vegetation into stonn drainage systems, conve}�ance ditches, stormwater ponds, or surface ti7ater. Use mulch or other erosion contro! measures �aheii soils are exposed foi- more than one week during the dry season or two days during the rainy season. � Implement water conservation practices to assure sprinkler systems do not "overspray" vegetated areas and discharge to hard surfaces such as sidewalks, driveways, and parking lots. Adjust sprinkler heads accordingly. Minimize water use so runoff does not occur or enter storm drainage systems. Use approaches to reduce water use such as those described in the Natural Yardcare program. http://yow�.kingcounry.�ovisolid��asteinatural�ardcarei��atering.asp "I�he E�ing Count}� �loaious W'eed Control Prog�am pro��ides best management practices for the removal of typical noxious «-eeds such as blackberry and purple loosestrife. Call 206-296-0290 or see http:!/ww��.kingcountv.gov/environment/animalsandplantsinoxic�us- ti��eeds:'�tieed-control-practices.asp� for more information. � ► i • � The following BMPs arc optio►��; unless tt�c �E�ui�� isli��imu�� E��c3�i�•ccl BMPs do not provide adequate source control: Integrated pest management(IPIV1), a comprehensive approach to the use oi pesticides is the most effective B`�ZP measurc that can be t�ken for herbicide, insecticide, and fungicide use. � See BMP Info Sheet 6 in Chapter 5 for inforn�ation on IPti�i. Fertilizers should be warked into the soil rather than dumped or bl�oadc.ast onto the surface. Determine the proper fertilizer application for the type� �f soil and veeetation involved. Soi1 shot�ld be tested for the correct fertilizer usage. Use mechanical methods of'vc�etation removal rather than ap�lyin� herbicides. � Krng County Stomiwater Pollutron Prevention Manua! January 2009 Landscaping Acfivities and Vegetation Management(continued) � An effective measure that call be taken to reduce pesticide use; excessi��e watering, and removal of dead vegetation involves careful soi] mixing and layering prior to planting. A topsoil mix or composted organic material should be rototilled into the soil to create a transition layer that encouraaes deeper root systems and drought-resistant plants. This practice can improve the health of planted vegetation, resulting in bette�r disease resistance and reduced �vatering requirements. Use native plants in Iandscapin�. �iative plants do not 1-equii-e extensive fertilizer or pesticide applicati��ns. For mare information or assistance in implementin�these best management practices, contact the Ku�e Count� Deparnnent of Natural Resources and Parks Water and Land Resources Division at 206-296-1900. y Reader Note: 'Tl�e above requirements are the minimum required B'vTPs. If these BMPs fai]to prevent dischar<�es to the stonn drainage�vstem, }ou �vill be asked to take additional measures to conect the continued poilution discharQes. January 2009 Krng County Stormwater Pollution Prevention Manua! Demolition of Build►��_, This activity applies to the removal of existing build'ulgs by controlled explosions, wrecking balls, or manual methods, and subsequent clearing of the rubble. Demolition of buildings can introduce a variety of pollutants into stormwater runoff, primarily suspended solids, but also toxic organic compounds and metals. Broken concrete can elevate the pH of stormwater. This activity can also produce air borne pollutants that must be controlled to avoid surface water c��ntamin�ti�n. e The following BMPs, or equivatent measures, methods, or �rac�ices are required if you are engaged in buitding demolition: Spray water throughout the site to help control fine materials and dust. The amount of water must be actively controlled and monitored to eliininate contaminated runoff from leaving tl�e site. Other approved dust suppressants are available. Avoid excessi��e and repeateci applications of dust suppressant chemicals. Place filter fabrie, inlet control measures ar a similarly effecti��e device in or around all nearb}� drains to prevent particles and solids from entering the storm drainage system. Filtering de�ices shall be placed at the beginning of the workday and the accumulated materials collected and disposed of properly before removing the devices at the end of tlie ��orkday. Filter fabric �nd other filte�r de��ices are cominercially available. Sweep surrounding street gutters, sidewalks, driveways, and other paved surfaces as needed to collect loose debris and garbage. Properly dispose of collected debris and garbage. Do not hose do�r�-n the area to a storm drain. January 2009 King County Storrnwater Pollution Prevention Manual Demolition of Buildings(continued) • ! I • • • The following B1VIPs are optional unless the above minimum reyuired B'�7Ps do not pro��ide adequate source control: A catch basin ins�rt confi�ured for sediu�ent and debris rei��oval ma�� remove some of the pollutants in runoff from this activity. Catch basin inserts require frequent maintenance to be effective. Carefull}� consider this when evaluating your options. � See Bl�-'IP Info Sheet 10 in C}lapter � tor i�Zf�nnatioil. For more information or assistance in implementu��these best management practices,contact the King Count� Department ofNatwal Resources and Parks Water and Land Resources Division at 206-296-1900. Keader Note: The above requirements are the minimum required BMPs. If these BNiPs fail to prevent dischar��rs i,� the stonn drainaRe syste�l�,��ou��ill be asked to take additional measures to correct the continued pollution dischar<,es. King County Stormwater Pollutron Prevention Manual January 2009 Building Repail-, Rernodeling, and Construction This activity applies if you are engaged in common on-site labor activities associated vvith construction of buildings and other structures, remodeling of existing buildings and houses, painting of building exteriors, and general exterior building repair wark. Stormwater runoff f'ro�n building repair, remodeling, and construction work can be contaminated with toxic hydrocarbons in solvents, other toxic organic compounds, suspended solids, metals, abnormal pH, and oils and greases. Concrete pouring is covered under Activity Sheet A-20,"Concrete and Asphalt Application at Temporary Sites." e The following BVIPs, or equivalent measures, methods, or practices are required if�-ou are engaged in building repair, remodeling, and construction: Do not dump any substance, wash water or liquid ��aste on the pavement, the ground, or toward a stonn drain or drainage ditch. Use ground or drop cloths underneath outdoor painting, scraping, a�id sandblasting v,,�ork and properly dispose of collected material daily. Use a ground cloth or oversized tub for activities such as paint mixinc and tool cleaning. Dispose of all �vash water from tool cleaning to the sanitary sewer system. l�ever dispose of��ash watei•to on-site yard drains or street drains. Never dispose of any �ti ash ��ater to a �to1-m draiil. Clean paint brushes and tools covered ��vith water-based paints in sinks connected to sanitary sewers or in portable containers that can be dumped into a sanitary sewer. Brushes and tools covered with non-��ater-based paints, tinishes, or other materials must be cleaned in a manner that enables collection of used solvents (e.g., paint thinner, turpentine, etc.) for recycling or proper disposal. � See B'�iP Info sheet 2 in Chapter > for infoi-�nation on disposal options. January 2005 King County Stormwater Pollution Prevention Manua! Building Repair, Remodeling, and Construction (continued) Lise a storm drain cover, filter fabric, or similarly etfective runoff control mechanism if dust, grit, wash water, or other pollutants ma}' escape the work area and enter a catch basin. This is particularly necessary on rainy days. The containment device(s) must be in place at the beginning of the workday, and accumulated dirty runoff and solids i��ust be collected and disposed of in an appropriate manner before removing the containment device(s}at the end of the ��orkday. For ��ample, a combination of a wet vacuum and brooms and dustpans could be used to collect accumulations of dirtv runoff. Drain co��ers. tilter fabric. and other containment devices are commerciallti� a��ailable it effective runoff control cannot otherwise be provided. If you need to de�vater an excavation site, you must filter the ��ater before discharging to a catch basin or discharging off-site. You should direct the water through sediment filters or traps or use an equi�alent method. The pH of water from dewatering activities must be monitored. If the pH is not neutral (7), discharge must not occur tu a drainage system until the water is neutralized through an approved method. Dewatering must also be assessed for other pollutants that ma� not be remo��ed by simple filtering of stonm�vater. If other pollutants are present, discharging the water to surface or stormwater systems may not be allowed. See Appendix D of the King Counn Surface ��%ater Design Manual, '`Erosion and Sediment Control Standards.'� � Routine Maintenance: • Store and maintain appropriate spill cleanup materials in a location l:?lo��n to all. Ensure that employees are familiar ��ith proper spill cleanup procedures. • Sweep paved areas as needed and collect loose particles for proper disposal. Wipe up spills with rags and other absorbent material immediately. Do not hose down the area to a storm drain. • Store toxic material under cover during precipitation events and ��hen not in use (such as overnight). A cover would include tarps or other temporary cover materials. �'� See Activity Sheet 3, "Storage of Liquid '�Iaterials Portable Containers.�� King Counfy Stormwater Pollution Prevenfron Manual January 2009 Building Repair, Remodeling, and Construction(continued) � / ! / � The following BMPs are optional unless the above minimum reguired BMPs do not provide adeyuate source controL• Recycle or reuse left over materials. A catch basin insert configured for debris and sediment removal may remove some of the pollutants in runoff from this acti�-ity. Catch basin inserts require frequent maintenance to be effective. Carefully consider this when evaluating your options. � Se� B'��1P Inti� Sl��ct l(1 i« Chaptcr � ii,i� m��l�e iTllui-tT�ati��i. For more information or assistance u� implementing these best management practices, contact the I�ing Count�� Department of Natural Resources and Parks Water and Land Resources Division at 206-296-19�0. Reader Note: The above requirements are the minimum required BMPs. If these BMPs fail to prevent dischar��es to the storm draina�e system. ��ou��ill be asked to take addirional mea�ures to con�ect the continued pollutio�i dischar�es. January 2009 King County Stomrwater Pollution Prevention Manua! III. OFF-SITE ANALYSIS Task 1 -Study Area Definition and Maps The Renton drainage basin map was used to verify that the site�vas fullv in the Cedar River drainage basin (See Figure 4-Drainrrge Bn�iir). Task 2-Resource Review a) Adopted Basin Plans Cedar River Drainage Basin b) Floodplain/flood�vay(FEMA) Maps Site is�vithin the 10o-yr floodplain(See Figure 5) c) Off-site Analysis Reports None available d) Sensitive Areas Folio See Figures 7-Fload Hazard e) Drainage Complaints and Studies None AvailaUle t) Road Drainage Problems None Available g) King County SoiLs Survey: See Figure 6-SCS Sc,il Sur�e� 11) Wefland Inventory Maps: No Wetlands i) Migrating Rivers Study None Available j) DOE's Section 303d List of Polluted �ti'aters Category 5�ti'�ters k) KC Designated��1�ater Quality Problems No��VQ Problems I) Critical Drainage Area'�,1aps: Not in Critical Draina�;e��reas. Task 3-Field Inspection Site visits have been made to gather information includu�g an analy�sis of the discharge from the site. �l�his field visit took place Tuesda��,February 9,2010. There were some minor precipitation events during th�� week prior,�vith partly doudj�conditions and temperatures in the upper 40's(degrees F)on the da�� ,f th�� site visit.Please refer to Task 4,Do�vnstream Analysis below for more information. Task 4-Drainage System Description and Problem Descriptions The site has a maximum change in elevation of 2-feet. The high point of the site is�t elevation 32 feet along the east edge of the property,with the low point of the site at approximately 30 feet at the�vest edge of die site. The site generall��slopes to the west. The drainage path for this site is a combination of sheet flow and closed pipe conve��ance. On-site soils are classified as Ur(UrUan Fill)per King Counn Soil Survev maps (See Figure 6). Per the geotechnical anal�rsis done the site soils consist mostl��of"Till". See(soils repart) in section VI for further information regarding the on-site soils. Upstream Analysis Logan Ave surrounds t11e east and south edges of the site and prevents offsite�rater froin enteru�g the site. North of the site is a Boeing air field that collects�vater on site and prevent5 offsite��-ater from entering the site. All runoff from the west side of t}le site runs��est into the Cedar River. There is no upstream��-ater that enters the Renton Stadium site. Downstream Analysis The existing site slopes generally to�vards the��est side of the school properti�.Runoff flo�vs off site to the Cedar River through rivo discharge points. The track,narth bleachers,and north parking lot all discharge directly to the Cedar River through a discharge point�vest of the field. The stadium and South parking lot discharge directl��to the Cedar River through a discharge point�+-est of the parking lot. (See Figure 3) COUGHLINPORTERLUNDEEN Pent�m�lemorial St�3�{ium 3 Kin�;Counh��ti'ashington Task 5- Mitigafion of Existing or Potenrial Problems � The site discharges directly to the Cedar River.There are no known problems��ith the discharge pipes between the site and the River. �The proposed development��ill decrease the net impervious area of the site, therefore runoff from the site�vill not increase. COUGHLINPORTERLUNDEEN �rnt�m\�1cm��rial5tadium � hin�;C��unh 1�a�hin�;t��n ! FIGURE � - FLOODPLAIN/FLOODWAY FEMA MAP i __ N � ' � .�_ _ � � _ _�� i I i -- ��r -- . '-- . _ - _ - + - _ __ 'i v --`�... � ~`,��"•_�. _'- _ � _ ' -1� .. �i � �-��' ' ``'�-.,, '�-'- . � . -�.;__-- `-ti.� s_�� ' 'y _ � __'--__ _ �_ _ . _ , � __ '- � � � � ` - --- � '-- ��- '; .-,�... ,. � • ---`�_ ' ._.. __. _.. ' . � � " 1 �, i .�.��_� :��;. r 4� , ._ . ti � '' I �.. •i� .. - - . '--_ y , , '�___ I _ ��''� ' Redeveloped partion �� ._ � � . _ ___ ____ ;� i ,; - --- ; -- � of the site is in red � � � ; ; - (2.5ac). ; - I_ _„ - _ �'.,., �I ` �.. --- � . r , � ' �k�.. ( ---= r� , ; . .. . . . .. . ., . . ..�__ �' '- . _ , � J "- •--. .:. � r---'� � '`_ ' 1 I � ' -" ' '-' _ � / I � i j • � � � ' - � `;y ,l , I I � � 'jl � ,/ I 1 ' � _ The only work taking -- I� I $ ' _ -� -- t -- place�vithin the flood ' _� "" � � � : �,I�� ' 'I �' � �'� "' -- � � aone is the demolition � � �. �� ` � � of an existing bathroom , l ' Base Flood Zone � � h , � + + building. The � (Digitized from l � �� j Uathroom will Ue � F.I.R.1�-1.I�1ap# � � ' replaced with a flat , � 53033C0977 F Map y�,i�i p �a revisecl May 161995 ;��;� � i� � �, , viewing area. No flood �4 ) � 0 � iq � ! stara e will be lost � � ��;� �j � � �� - g . i 's ��' t , �. The removal of the �'y : � �_'�^�' ' � � �I 4 �� l� - ��- , , � �� bathroom�vill onl`� �( '" � , � ' ' �.� � � ' � increase the available 1 � -�� - �,, i;i �`-- r ��i� � ��. I + � � ' � • � � flood storage. � r �� _ '� Mi � �" ' . ; , �( fi 1`�`"' � ; , : ' � ,. - : � . �II ,,. �- r F: , r �'` . � ' y� {r �. f ' � � �� ' ,.� � � �� '.a � ■ e a I � ! , • � • 4 •� i!, —� ; `i � �! � ♦ � ;, YI' _ � ♦ , .. . _ � i 'i ♦ \`` - � '-- i__ ';r4_ � /��• ,I �•��. i 1. � � .� � - t�F '' / ../ � Y' -� � \,.,�}�� i '', �/� % �. r` _ ',s . ry�t � . . . _ � � _�`,�' - �� i. - .1 - -� � " , �� +�� ,��" "_ � . . � / � �' / =' �_ _" - � r/ , j. _ -' _ - � � � . i = ' . . I �- .. ` � - _ ' . . -� _..-� _ - - _ _ _ _-�_ _ _ -��Y-l-`�_ __ -_ ��=_=---_- - _ �-_- _ .-_ - �_ _ - - Ordinary Hi h y----- __-.-�� =_- __ -- �----�� -1'ater I�-larkg �`��--`'� . - �- - -Y��__ - _ -_ � _ ____ .�==�"`.�---- COUGHLINPORTERLUNDEEN Renton Memorial Stadium Kin�Counh��ti'ashingtrn� FIGURE 6 -SCS Soil Survey i i U. S. DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE ��c �/ R.4 E. R.S E. SEAT7L£(CITY P.O.)10 M1.12�?V� 6� � 47=30' � Y� . _ � '/, 1 � . I . •• 111 �Y` ^'n�� B M. � �''•� � � �! �� h ��; � '��;: i � B Ma � i � ��-�� '� « � � F:�>"�i. , �� • � � �.� � w,��' ' l, �•• �.�•. �•y'S...\•"$uDCid' !1. �i �'� � 1,`�..•�, �/ I ��t� � � } � ''� I E '� �• ' , No I �� 1` i . �� ' ••t• .� `7 l � \� '� .r.. •? I �j 1� .I: C ! �� F..� ' � � i: '�1 J agp . , i Bl� Riyer Y .�' •. t� �',.� `�.��.'�: , , �� a R o�� ,� j ,f,. :�4 � �' \, , `, I :{+�••��.~��o•• . . 'r' y�,l gC• ■ ` j�'&'__¢ � `� th�eti �• •� •I• � b;ta�M,.� BM �� '� ��1n ;el I I J '.;` �' � /� � ;�-- �3 •� � .� �• � � -- �(v!' ��_ � _� � � * �• .. . BeC �G i ; //i�' � -��, . r . 0 �� '; ,BeC � n I � •'M•• • • . • • � • s ' y Il'` ..I m 25 ' • ,�" , �� i� I 1, � ' F m ISeC `` • •t. • .'r: a c ��, :� �; ' ¢ p � BeD � � ,BeC, .�. �� ,� ,. � �< ' �p ` p `�jl.:;� _ ;l�. �'�',•a '.ti �� 5 'R„ R o,a o ru �. __ R �, �a •;s. F d , o �,� �H O � � r h r o� ?. _E • , I G � i , Ri2.� � -�,_ � ; � ) /Wo .�a� _ _ � , �,� �• � �, w`c � _ �. i•K u� % -- — - --- � r � +�•-+- ��, I .�g Pu U r py� 13 ; � � r •� �:: � � � � j � BeC Golf ourse I I + � __�sta� F �Wo� � �" � c: . '� . _ - ;r A � � PA �� % � � BM � � � /%� �� '�.ili � � ,a � �� i E : , ,`z', �f � .� 30,.= �Sew He �RTN . � ' �` � • h � �'� �ii/�eJ�,DisP ai �:� �� 2 � N� �t�• o U- s . :12G :i f i �O � � '� '•i ' � J ��'_ ZJ� � ��•� •� �I '.. . . M.16 9 •'� •. y �,�,�'^,.` � Pu ��/ I � � � � r�,. -:t �C� 1 � : � ` ` .� �` w L� ';,:.T . I UI ,:Ir, '�', • ) '� � � \ ..� ` ��Longacre�l�;i� • � oU Pu ••� Ui•• '✓ '' F � � ..�,, O :�r;'� ' �'*'��, II� •- __,� . o:� ' '1 i. ; R �; , • � 1 �dCS 4�.i� J� ••�I�I i i � �1=�'' Py � Wo ' eD iii iBeC �''I Fi � � •N. .0, T � .� 0 -� ,r � �� U_� �ii'.1 � � Wo Track � „ �i�l�illv�l2.1/. .?�� o�s �n11'�� -�i /��-- -- -- — — — I$0 f B . Site Soils Are(Ur)-Urban Land The Geotechnical repart found mostl�� (Quaternary Alluvium)Soils onsite. ' These are generally Till Soils COUGHLINPORTERLUNDEEN Renton I�temorial Sta��ium � � King CountK 41'ashington FIGURE 7-SENSITIVE AREAS (FLOOD HAZARD) � I City of Renton Sensitive Areas Flood Hazard � _.:: i. -.; � N , ;` -:,' -- . / , � �� I (j 4 Ili r�.....i�.._ - .� � . ` i � ,,� �' 6 _ r � `I i � � ! � � I _ i I' { �� .. • ' � �'�� - � ... . . �- `'� �"� _� ` .JI �, � ��-�.�' ` �' '. - : �`�.�-w--�';._. �:�. _ i ,� � s � r P -� i . �,+� �� ' ' -_ - � ll- � �' � ' i ' < � :. _ , � �, I__ � . �. � _ � � i � '� }' ' I r '_ ' µ �' ' ' ' ' ��. 'I- � --_ ' � ' _ I � SI7'E i •°I �� . _ ., _ - _ � � � .�� __ . , - �i,. -, -_; ,_ ,. ~ - - . �-'�'- ',: ,�,._ : �E ' � = ''_. II -T..� �.I,. .+ � .�j'i-r' ��_. •S� i�+ _ - i _ 4 I:-�.��1� I ` 5_Y� ' � I...i : � ,' . �i - � -... �_-. 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' �.f:'` � ,l ' j ! i _i � -a. , - IL� ' = L t � j � • �, - __>� T , i -�- __ : � '..,.� • �� '1 ..y r < �-� i i= � ' y " y� , `I I i S� , � , i � -I .i ; i I _ �:i- � :. `�' i r _��-: I ,� ,; � � �' _ �' � i� • ,jt . � `�\'' ` _ �a.fl � ..� J •1~ 'I�I . �- i I11'�'v. �r � 3, - j`I'�[1 .. _ �. . . 7._ I� y I_ . . '. >i4 �I I . ' � _ i _ ��"1 �`� ' _ • .J �.�'�� ?�� -�i� _ - • -� -_ y� .3� � -�� s. � I � ,.� il~ .s� R, � �1I �'1. �_ • _ . _ � �.}��: ,_�i -t ' � .e - �. H �'r i _ - .. . I-: . ^'�yp, _ ; i I : .� � - _I..a � :. ;I � ' .. i .. ' .:. . � - �� . .� ,� . .1 ' / , � - . �. .ji �"7 �. - i� � -=, _ , -'�_ � ._� _ , ,., ,, � -�" ;, � _ � -,- � .� i. .F =� � -- . , �. �- -- _ � �.. � _ , , '; , 'j ;� i�. � � �; .,� j i: ' _ �!... � - ;i _� I� . �F' � �� _ � 'I �I � � L;�_.' II_•I �� ' ��. ' ,� . �', I -- ' _ . •� .. _ ..._ . - , —� PuWic Waks Departrnent c z�.�.m�.ne��sra:a Hazard Condition rc�ami��servroes ,,,, ,,,m Critical Iflhastructure R.NaeOrtie.D-V�sneski � ' - FboC Hazard Pmted m May 21.200D - .. � j� �o�ee oeparti^e^� oYa 3arQ:Ra�waMc.u�uec SyticK.lt�uvYd savtec i y �-•••• 1�Frc Scauonc �J rrt��Y r v��r� -- � w�eY reacm ceit. r J � (I '�J (' _-. � sa,o,n COUGHLINPORTERLUNDEEN Renton Atemorial5taciium Kin Counn-�1�ashin ton IV. FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN Existing Site Hydrology(Part A) , The existing site totals 14.�acres and consists of an existing Stadium,parking lots,landscaping,track and field,sidewalks,and ticket/bathroom buildings.Only 2.5 acres of the existing site will be part of the redevelopment project. The site slopes in a westerly direction with drainage described in Section III , Do��nstream Anal��sis.T-hese conditions are summarized in Table 1 belo�v. Table 1 -Existing Site Conditions Area Breakdown , Land Cover Area Description ', Impervious Area 17.28 acres Building roof,drive��a�-,parking lots,sport field ', Pervious&Landscape 3.16 acres Associated landscaping,north grass field ', Total Site 1�.�acres Total site area ' Developed Site Hydrology(Part B) ', The de'veloped site hydrology will decrease the amount of impervious area by 0.03 acres. A new north ', ticket booth/bathroom will be installed,but the existing north bathroom,ticket booth,and a portion of the ', private parking east of the stadium��ill be removed and replaced�vith pervious surface. This�vill result in ', no net gain in impervious area after the site development takes place. A summar}'of the basin information ' is shown in Table 2. Tnble 2-Dez�elo�ed Site Conditions Aren Breakrlozo�t Land Cover Area Description 11.25 acres Building roof,driveway,parking lots, Impervious Area sport field Pervious&Landscape 3.19 acres Associated landscaping,north grass field Total 14.�acres Total site area Percentage of Impervious Area 77.9°0 Performance Standards and Flow Control System (Parts C and D) 7he site c�ualifies for direct discharge exemption per page 1-37 of the KCSWDM. Under the exemption a site is exempt from the flo�r control facility reyuirement if the area drains to major receiving water. T7�e , lower Cedar River is listed as major receiving water under table 1.2.3.B. ', a)As part of the exemption requirements the site is within?-:,mile of the Cedar River. ��, b)The conveyance system discharges to the ardinary high water mark through already existing ', P�P�• ' c)The conveyance system�vas previousl��designed to handle the runoff from the site and there are , no kno�m problems. The proposed net impervious area will not increase;therefore the runoff rates from the site will not increase. d)The discharge locations to the Cedar River are already adequately stabilized and have no know problems. e)The runoff from the site will not increase after this development. COUGHLINPORTERLUNDEEN Rentcm hiemorial Stadium 5 King Counn-��'ashington Water Quality System(Part E) Standard Requirements Under core requirement#8 a project must add or replace over 5000sf of I'GIS before w�ater quality treatment is required. 1�he proposed development is replacing over 25,0000 sf of impervious area,but all of the area is considered non pollution generating. Onl��roof and pedestrian�valk�vays are being added or replaced on the north side of the track. On the south side of the stadium the impervious courtyard being replaced is located�vithin a gated fence�vhich is primarily used b��pedestrians. On an occasion a bus may park in the court��ard during an event. On page 1-4 of the 2009 KCSINDM,it states that PGIS is considered a surface subject to"regular"vehicular use. Maintenance access roads and fenced fire lanes are not considered to be surfaces that are regularly used by vehicles. The couri��ard being replaced is primarily used for pedestrian access to the stadium and is rarelv used by vehides. The court�-ard is not regularl��used by vehicles and therefore�vould not be considered a pollution generating swfaces under the definition in the 2009 KCSWDM. Because 5,OOOsf of PGIS is not being replaced or added the site is exempt from pro�riding water qualih�far the proposed redevelopment. Spill Control Spill control is reyuired for projects constructing or replacing onsite pipe systems that receive runoff from pol(ution-generating surfaces such as parking lots(7.2.-�-G). `There is no new pollution generating surface being added and existing parking lots will not be�listurbed. Flow Control and Discharge Requirements The proposed project has direct discharge to the Cedar River. According to d�e KCSI�ti'D�1 page 7-�7,sites that have direct discharge to the Cedar River are exempt from detention. COUGHLINPORTERLUNDEEN Renton�1enu�rial Stadium 6 Kin�;Counh•�1'atihingtcm V. CONVEYANCE SYSTEM ANALYSIS AND DESIGN This section discusses the criteria that will be used to analyze and design the proposed storm conveyance svstem. Standard Requirements(based on KCSWDM and SAO): 1. Facilities must cor�z�e��the 100-year flozv Zvithorrt overtopyi�:g the crozvn of tlte roarlrvay,flooding F77l1I1I1I1gS�and if slteet flozv occurs it rrtust pass t)trougli a clrair�age easernent. The existing drainage facilities are not being altered and have no known overtopping issues. 2. Nezu pipe sJster�is and crilz�erts must cortz�ey t)te 25-year flozv zuith at least 0.5 feet of freeboard. (1.2.4- 1). The new pipe systems�vere designed to convey the 25-year flow with at least 0.�feet of freeboard. 3. Bric�ges�riust co�►ve��tlie 100-�ear flozv artd provide a ruirti»nnn of truo feet, z�an�ing r�p to six feet, of clearance based ori 25%of the»iean c)Tantiel ruidth. (1.2.4-2)(4.3.5-6).N/A This project does not propose , a bridge. 4. Drai�iage ditclies must convey the 25-�ear flow zvith 0.5 feet of freeboard c�nd tl:e 100-year flozv zvithout oz�ertopping. (1.2.4-2). Drainage ditches will be designed to convey the 100-year storm event with 0.5 feet of free-Uoard for this proposed development. 5. Floodplain Crossiugs►nust�eot iricrease tlie base floor�elez�ario��by�nore than 0.01 feet(41(83.C)J an�i sltall not re�iuce t)te flood storage z�oluuie(37(82.A)]. Piers shall itot be constrr�cted in the FEMA floodraay. (41(83.F.1)]. The oniti-�vork being done��-ithin the floodplain is the removal of an existing bathroom. A flat viewing area will be kept at or below existing grades. No storage volume�vill Ue lost. 6. Strea�n Crossirtgs sliall require a bridge for class 1 streauts tltat rioes r:ot distirrb or banks. For type 2 ai�d type 3 steams,ope�i botto�n crilz�erts or otlier»tetltod r1►ay be used tliat zvill riot hanrt tlze streant or 1?[Iitlllt fish passage.[60(95.B)]. There are no stream crossings associated w�ith the construction of dlis project. 7. Discharge at riatrrral locatiort is reqrrired and mr�st proriuce no significant i�npacts to the dozvristrearn property(1.21-1). The project w�ill discharge to the existing discharge location. There are two existing discharge points from this property. The proposed storm s��stem�vill continue to discharge to those poinis. On-site Conveyance Existing Conditions: Storm��ater discharges from the property at t�vo locations: the north��est and southwest corners of the property. North�oest: (See Section 3 and figure 3 for further information). sors r1 it��est: (See Section 3 and figure 3 for further information). ♦ COUGHLINPORTERLUNDEEN Renton h9emorial Stadium 8 King County 6b'ashington Developed Storm system description: T1�e developed sites conveyance system�vill not change from exisHng conditions.The renovated stadium will discharge to the storm system it currently discharges to. The north Hcket booth and bathrooms will Ue removed and replaced �vith a new ticket booth and bathroom. "I'his ne�ti�building will have its roof downspouis connected to the existing convevance s��stem that the existing ticket booth's roof sheet flo�vs to. KCRTS Modeling: The largest portion of new pipe is along the ne�v north building. The stadium��ill reconnect it's downspouts to existing storm,otherwise no new storm is being added along the south side of the track. I�he proposed 6-inch pipe sloped at 0.5°o picking up the new north building has been analyzed to confirm that the pipe can handle runoff from the roof and nearby landscaping. 0.27 acres of impervious roof and 0.16 acres of landscaping will drain into the proposed storm line. Calculations on the next page show that runoff from this portion of the site��ill pmduce the follo�ti�ing flo�vs: Q�;=OZ-�6cfs Q,00=0.365cfs HHCaIc has been used to run �9anning's ec�uation to analyze the c�pacifi�of a 6-inch pipe at 0.�°0. 'I hr ma� capacity of the pipe is 0.-�:�cfs. T71is is higher than the 100-��ear starm therefore no capacih� issues am andcipated in the ne�ti�storm svstem that�aill pick up runoff from the new north buildin�;. Outfalls Energ�,dissipation is reyuired for all outfalls, rock er��sion protecti�,n at a minimum. (1.?.3-�). E�istin�; ener��dissipation has L�n provided at the outlet pip��s. COUGHLINPORTERLUNDEEN Renton�femorial Stadium 9 KinK Counh•11 ashin};h�n MGS FLOOD PROJECT REPORT Program Version: MGSFIood 4.07 Program License Number: 200610002 Run Date: 09/07/2010 11:34 AM Input File Name: MGS Flood.fld Project Name: Renton Memorial Stadium Analysis Title: Comments: PRECIPITATION INPUT Computational Time Step (Minutes): 15 Extended Precipitation Timeseries Selected Climatic Region Number: 13 Full Period of Record Available used for Routing Precipitation Station : 96004005 Puget East 40 in 5min 10/01/1939-10/01/2097 Evaporation Station : 961040 Puget East 40 in MAP Evaporation Scale Factor : 0.750 HSPF Parameter Region Number: 1 HSPF Parameter Region Name : USGS Default *"''****'**"'`*"***'''***WATERSHED DEFINITION **'`***"**'`*�**`*'"`**** ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Subbasin 1 ---------- -------Area(Acres) -------- � Till Forest 0.000 Till Pasture 0.000 Till Grass 0.160 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 0.270 I Subbasin Total 0.430 **""'*"'"'''**Compliance Point Results *'"**'`****'`** Scenario Predeveloped Compliance Subbasin: Subbasin 1 Scenario Postdeveloped Compliance Subbasin: Subbasin 1 *** Point of Compliance Flow Frequency Data *** Recurrence Interval Computed Using Gringorten Plotting Position Predevelopment Runoff Postdevelopment Runoff Tr(Years) Discharge (cfs) Tr(Years) Discharge (cfs) ------------------------------------------------------------------------------------------------------------------ 2-Year 0.115 2-Year 0.115 5-Year 0.146 5-Year 0.146 10-Year 0.182 10-Year 0.182 25-Year 0.246 25-Year 0.246 50-Year 0.292 50-Year 0.292 100-Year 0.365 100-Year 0.365 200-Year 0.366 200-Year 0.366 ** Record too Short to Compute Peak Discharge for These Recurrence Intervals **"`* Flow Duration Performance According to Dept. of Ecology Criteria "** Excursion at Predeveloped '/zQ2 (Must be Less Than 0%): 0.0% PASS Maximum Excursion from 'hQ2 to Q2 (Must be Less Than 0%): 0.0% PASS Maximum Excursion from Q2 to Q50 (Must be less than 10%): 0.0% PASS Percent Excursion from Q2 to Q50 (Must be less than 50%) 0 0% PASS ------------------------------------------------------------------------------------------------- POND MEETS ALL DURATION DESIGN CRITERIA PASS ------------------------------------------------------------------------------------------------- 09/07/10 Renton Memorial Stadium (6" Pipe @ 0.5°•) Manning's Eq�sation fcr Uni�orm Flow in a Circular Pipe Input Quanti�ies Dia�.eter: 6.Q000 in ' Manrinc's r.: C.0120 Slope: �. 5000 � Calculated Flow Rate: �. 4295 cfs Ca-_culated Vel��city: 2. 1�76 ft/s Ca_culated De�tr: 6. 0000 in Calculate3 Quantities Area Of Flow: O.i964 sf Tn'ettea Ferimeter: 18.8496 in Hydraul�c RadiLs: 1.5000 in d/D Ratio: 1 . �0�0 parts Velccity Hea��: . ��43 ft Crit-�cal Dep�h: � . �020 �n Ful1 Capacit�,-: .4295 cfs Max �apacity: ;� .4621 cfs HHCalc, Version 7.Gs Eagle Point, 4131 �n'estMark Drive, Dubuque, IA, 520�2, 1-8C0-6�8-6�65 i VI. SPECIAL REPORTS AND STUDIES 1. Geotechnical Engineerin�Report;Renton Memorial Stadium Additions Renton,1��ashington. Prepared bv Associated Earth Sciences,Inc.on December 10,2009. COUGHLINPORTERLUNDEEN R��nt�m\trm��rial�l,ulium l�) h�n�C�,unK 11�a,hin,;t��n _ ;1`Y;_ :—�±,I�.,", i:}��._',,.�- . J� I -�~ �' ,�� - ' ' .''p`..j' Geotechnical Engineering ��O�1�t�d � �C1�Y��S' I�Co - � :: ;' �,-, '-,-- . �G�lG'�1nGl�Y! (/1/�1�,2� ��Gll�l'Of.1e�U1ce __:_._:.�.._ ..y _ .:�.�: o \ J— • .'.�2-,;._.�.sa�r.�. cJ�— Subsurface Exploration, Geologic Hazard, Water Resources and Preliminary Geotechnical Engineering Report i , �,�'t�, , -`�`;�'. R�,I�1rTOI�1 1��,1�g��, ��'�I��gJi�� '��,{< ;� . ;�r ��JlJl1 H�1'V� � : = i;:_` _,p�J y J �/ '. � ''-�' Renton, ��Jashinti7ton _-�� _��f, . Environmental Assessments and Prepared fc�r Remediation 12enton School District , � clo G�-eene-Gasa�vay Architects .�� -- -- __R -.-{.� ,�:.�.:- Project No. IL1:090396:� � : . ,-- _ ,.F.'-�'-r�;`., December 10, 2��9 Sustainable Development Se�-vices ��-�-- � .�'�� .�.; � `t. - - - :��_3 �i '� . "��.- ,�t� ,� ..+ .:,,,%�. - 1�: r: ♦i i Geologic Assessments Ass�ciated Earth Sciences, Inca � 0 °�� :�,� Ce�l��z�iny a��z5��j�'af�S'ef^vice December 10, 2009 Project No. KE09039fA Renton School District c;o Greene-Gasaway Architects P.O. Box 4158 Federal �Vav. �'�'asl�in��ton 98063 Attention: 1�1r. Cal��in Gasa��av Subj:ct: Subsurface Exploration, Geol�gic Hazai�d. and Preliminary Geotechnical Engineerinc Report Renton Memorial Stadium .Additions 406 Logan Avenue North Renton, �T�%ashinaton Uear �Ir. Gasa��av «'e are pleased to present the enclosed copies of the abo�e-reterenced report. This report �ummarizes the results of our subsurface expioration, geologic hazard, and geotechnical engineering studies and offers preliminary recommendations for the design and development of rhe proposed project. Our report is preliminar}� since project plans were under development at the time this report was «�ritten. We should be allowed to review the recommendations presented in this report and modi�� them, it needed, once final project plans ha��e been formulated. ��'e ha��e enjoyed worl:ing ��ith yol� �n this �ttiil}� and are c��nfident that the reco►nmeiidatic�ns presented in this report will aid in the successful completion of your project. If yoii sholild have am� que�rion5 i�r if ��e czn be �f additional help t�� ou. please do not hesitate to call. Sincerel� , .�SSOCI�TED EARTH SCIENCES, INC. I�irkland, �Vashingtou �.� J;l�+', . t � Kurt D. Merriman. P.E. Principal Engineer �:i�nv�n r:�o�o��,,, E�:�:�� ;�rr,��,:��,,,�..k�.��.i� liirl:land � E��erett ° racoma 4?�-8?----01 42�-259-0522 273-�22-2992 ��ww.aesgeo.com SUBSURFACE EXPLORATION, GEOLOGIC HAZARD, AND PRELIMINARY GEOTECHNICAL ENGINEERING REPORT RENTON MEMORIAL STADIUM ADDITIONS Renton, Washington Preparecl for: Renton School District c/o ('Treene-Gasa�vay Architects P.O. Box 4158 Federal Way, Washington 98063 P�•epare� Uy: Associated Earth Sciences, Iuc. 911 �`'' Avenue, Suite 100 Kirkland, Washington 98033 425-827-7701 Fax: 425-827-5424 December 10, 2009 Project No. KE090396A Suhs�uface E�plantiai, Geologic Ha<,arci, Renton Mentorinl Stadirun Additrons and Preliminnry Gentec/t�tical Engineering Report Re�ttoii, Wasliiii�to�� Project mid Site Co�iditroits I. PROJECT AND SITE CONDITIONS 1.0 INTRODUCTION This report presents the results of our subsurface exploration, geologic hazard, and preliminary geotechnical engineering study for the proposed additions to the Rentoii Memorial Stadium located at 406 Logan Avenue North in Renton, Washington. The site location is presented on Figure 1, "Vicinity Map." The existing building locations and approximate locations of the ' explorations accomplished for this study are presented on the "Site and Exploration Plan," Figure 2. In the event that any changes in the nature, design, or location of the improvements are planned, the coiiclusions and recommendations contained in this report should be reviewed and rnodified, or verified. as necessarv. 1.1 Purpose and Scope The purpose of this study ��as to pro��ide subsurtace data to be utilized in t}ie prelimin�r�� design and development of the aforementioned project. The study included drilling fow• te�� borings and performing geologic studies to assess the type, thickness, distribution, and physical properties of the subsurface sediments and ground water conditions. Geologic hazard evaluations and engineering studies were also conducted to determine suitable geologic hazard mitigation techniques, the type of suitable pile fo�indation, pile design recommendation�. anticipated settlements, floor support recommendations, and site preparation and draina�e considerations. This report sur�unarizes our current fieldwork and offers geologic hazar�l mitigation and preli��inarv de��elopment rec��me�ldatio�is based ��n o�ir present understandinU of the project. 1.2 Authorization VVritten authorization to proceed ��itl� this study ��as granted by �1r. Rick Stracke of the Renton School District No. 403 (District). Our study was accomplished in general accordance with our scope of work letter dated October 20, 2009. This report has been prepared for the exclusive use of the District and its agents for specific application to this project. Within the limitations of scope, schedule, and budget, our services have been perfoi•med in accordance with generally accepted geotechnical engineering and engineering geology practices in effect in this area at the time our report was prepared. Ow- observations, findings, and opinions are a means to idetitif}' and reduce tlie i�iherent risks �o the o��ler. No othei� ��arranty, e�press or implied, is made. December 10, �(Xl9 ASSOCIATED EARTH SCIENCES, l:�'C ,'PLiib-KL•090396r.'-Pro�e<rs'?009G39,'K-'iiP Pave 1 Stibsu�face E,cplot-atio�i, Geologic Ha:ard, Re�ito�i�Ylet�iorial Stadiier�z Additioits alid Prelimina�y Geotecluiical E�igi�ieeririg Repot-t Renton, Washing�a2 Project and Site Conditiais 2.0 PROJECT AI�D SITE DESCRIPTIO�,' This report was completed with an understanding of the pro.ject based on preliminary discussions with the design team. The pro.ject site is the existing Renton Memorial Stadium, located at 406 Logan Avenue North in downtown Renton, V4'ashington. The existing stadium includes a main staditim building at the south side and a grandstand structure at the narth side, with paved parking to the northeast arid south, and a synthetic athletic field and track between ' the stadium structures. A grassy discus/javelin area is located to the northwest of the stadium. Site topography is relatively flat within the areas proposed for construction. A roughly 6-foot- high berm with a jogging trail is located along the west side of the subject site. The Cedar River is located on the opposite side of this berin, and flows north�vard to�vard Lake Washington. The proposed pro.ject will include a building ad�lition(s) to tl�e main south-side stadium building. The areas currently proposed for the building addition are covered with existin�� paved surfaces. The construction details have not yet been finalized by the design team:. however, we anticipate that the addition will be constructed close to existing grades, and that hardscaping for the project may include segmented paving units. We also understand that a future addition is currently under consideration for the north grandstands, and that the scop� ��t our subslirface e�ploration for this sttidy included tl�e areas adjacent to the north grandstand. 3.0 SUBSURFACE EXPLORATION Our field study included drilling four exploration borings ��ith a u-ailer-mounted drill ria to gain subsurface information about the site, and collecting soil samples. The various types of sediments, as well as the depths �vhere characteristics of the sediments changed, are indicated on the exploration logs presented in the Appendix to this report. The depths indicated on tlie boring logs where conditions changed may represent gradational variations between sediment types in the field. If clianges occurred bet��een sample iritervals in our borings, they wet-e interpreted. Our explocations ��ere approximateltir located in the field by measuring frrnn known site feature�. The conclusions ancl recommen�la�ions presente�l in this reporl are base�l on the t��ur exploration borings completed for this study. The number, type, locations, and depths of the explorations were completed within site and budgetary constraints. Because of the nature of exploratory work below grouiid, extrapolation of subsurface conditions between field explorations is necessary. It should be noted that differing subsurface conditions are sometimes present due to the random nature of dePosition and the alteration of topography b} past grading andlor filling. The nature and extent of any variations between the field e�l�l�i-ations ma�� not become fully evident until construction. If variations ai-e obsei�ved at that Dece�nber 10, 2009 .ASSOCIATED EARTH SCIENCES, Irb'C. iPL ih ,ti"En:iri_i95:'=-Prqre��t i:�90�9GfKEl'.b'P Pa�Te 2 Sc�hsrufnce Eaploration, Genlogic Hnza1'd, Renton Mentorial Sradiuni Additio�ts and Preliminary Geotedu►ical Engineering Reporr Rento►t, WQSI2Illg1071 Project a�id Site Coriditions time, it may be necessaiy to re-evaluate specific recommendations in this report and make appropriate changes. 3.1 Exploration Borings The exploration borings ��ere completed by ad��ancing a �.2�-inch inside-diameter, hollu��- stem auger with a trailer-mounted drill rig to depths ranging from 70 to 75 feet. Below the water table, the borings were successfully completed with little or no heaving conditions with water stabilization drilling techniques. During the drilling process, samples were obtained at generally 5-foot-depth intervals. The borings were continuously observed and logged by an engineering geologist from our firm. The exploration logs presented in the Appendix are based on the field logs, drilling action, and inspection of the samples secured. Disturbed but representative samples were obtained by using the Standard Penetration Test (SPT) procedure in accordance with Ame1-ica�l Society for Testi�zg a�id Material.s� (ASTM):D 1586. This test and sampling method consists of driving a standard, 2-inch outside-diameter, split-barrel sampler a distance of 18 inches into the soil with a 140-pouncl hammer free-falling a distance of 30 inches. The number of blo�;�s for each 6-inch interval is recorded, and the number of blows required to drive the sampler the final 12 inches is kno«�n as the Standard Peneti-ation Resistance ("N") or blow count. If a total of 50 is recorded within one 6-inch interval, the blow count is recorded as the number of blo�;rs for the correspondina number of inches of penetration. The resistance, or N-value, provides a measure of the relative density of granular soils or t1�e relative consistenc�� >f cuhe�i��e s��il,; these �alues are plotted on the attached boring lo<��. The samples obtained from [�1C �plit-barrel sampler ti�`re cla��ifieci in the fiel�l und represeiitative portions placed in ��ratertight containers. The samples were then transported tc� our laboratory for further visual classification and laboratory testing, as necessary. 4.0 SUBSURFACE CONDITIO\S Subsurface conditions at the pro,ject site were inferred from the field explorations accomplished for this study, visual reconnaissance of the site, and review of selected applicable geologic literature. Because of the nature of exploratory work below ground, interpolation of subsurface conditions between field exploratioiis is necessary. It should be noted that differing subsurface conditions may sometimes be present due to the random nature of deposition and the alteration of topography by past grading and/or filling. The nature and extent of any variati�ns het�veen the field explorations mav not become fully evident until construction. Decenrher 10, Z009 ASSOCIATED EARTH SCIE,ICES, 1:'�C lPL:ib-KL-09039�-I'-P�ojerts','(X19G396'.KEIWP Page 3 Su6surface Fxpinration, Geologic Hazard, Re�zto�z Memoriaf Stadiunz Additioits a�id Prelimi�iary Geotechnical E��gineering Repoi7 Re�ito�i, Wasltirrgton Projecr and Site Co�iditio�:s 4.1 Stratigraphy Fill/Modified Groas��l Man-placed fill, consisting of silt or silty sand with gravel, was encountered below the grass sod in exploration borings EB-3 and EB-4 to depths of roughly 3 to 4 feet. The fill and the upper surface of the underlying alluvium are in a loose condition. Fill is also expected in unexplored areas of the site, such as the area surrounding and under existing paved areas, structures, and in the existing underground utility trenches. Due to their variable density and coiitent, the existing fill soils are not suitable for foundation support. Quaternary Alluvium Sediments encountered beneath the asphalt and fill generally consisted of interbedded clean sand, silty sand, clayey and lean silt with occasional lenses of gravel, peat, and other organics scattered throughout the soil column. We interpret these sediments to be representative of recent and �lder alluvium deposited in former channels of the Cedar River. The alluvium extends beyond the depth of our deepest exploration (7� feet). In general, the alluvium encountered in our explorations is very loose/soft to medium dense. Between roughly 49 and S7 feet at exploration borings EB-1 and EB-2, the alluvium occurs in a dense condition, is relatively more granular, and contains abundant gravel. These sediments occurred in exploration boring EB-3 between roughly 43 and 53 feet. Exploration boring EB-4 differed slightly, as dense sediments were not encountered until approximately 68 feet below the ground surface, although a medium dense gravel lens was encountered at roughly 44 feet. The saturated soil in which "N" values do not exceed roughly 25 has a high potential for liquefactioii-induced settlement. Iii addition, the abundant layers of very soft clayey and lean silt are subject to consolidation settlement under the new building loads. Therefore, structures will require deep pile foundations for support. In general, the soil where moisture content is within the compactable i•ange is considered suitable for reuse as structural fill. It should be noted that where soils are above their optimum moisture content for compaction, their reuse as structural fill during all but the driest times of the year will be difficult. Existing alluvial soil was observed to contain silt and is considered moisture-sensitive. With appropriate remedial treatment, the soil, where moisture content is within the cornpactable range, may be considered suitable for support of slab-on-grade floors, hardscape, and paving. 4.2 Geologic Mapping Review of the regional geologic map titled Geologic Map of the Renton Quadra�igle, Kirzg Counri�, Was/zi�zgton, by D.R. Mullineaux (1965), indicates that the area of the subject site is underlain by modified land with fill (afm) and recent alluvium associated with the nearby Decenzber 10, 2009 A,SSOCIATED EARTH SCIENCES, INC. lPLitb-KL•09f1396.1?-Piojeasl20090396�KEIWP Page 4 Suhsiufnce E.tploration, Geolagic Ha;,ard, Renton Meniorial Staditun Additions arid Prelimfna�y Geotech�zical Engineering Report Rento�i, R�aslii�tgtorz Project mid Site Co�iditio�is Cedar River (Qac). Our interpretation of the sediments encountered at the subject site is in general agreement with the regional geologic map. � 4.3 Hydrology Ground water was encountered at an average depth of approximately 6 feet across the site. This depth corresponds roughly to the water level in the nearby Cedar River. However, ground water depths reported during drilling may not represent stabilized ground water elevations that would be recorded in a pro�erly constructed monitoring well. Ground water encountered in our explorations represents the regional tinconfined ground water aquifer within tlie Renton basin. Ground water may be encountered in excavations that penetrate into the underlying alluvial soils. To our knowledge, no deep cuts are planned that will intersect the regional ground water aquifer. If sucti cuts will be made, significant ground water dewatering operations will be necessary. It should be noted that fluctuations in the level of ttie ground «�ater may occur due to the time of year, variations in rainfall, and adjacent river levels. , _ ' Decentber 10, 2009 ASSOCIATED EARTH SC/ENCES, INC. !PL itb-KE090396�I3-Projecrsl?0090396!KL•IWP PagC 5 Subsu�face Exploratio��, Geologic Hn�ard, Reiuon Memorial Stndiuni Additions a�td Prelimina�y Geotechnical Engineering Reporr Renloli, WasJtingto►t Geologic Ha<,ards and]I�litigations II. GEOI.OGIC HAZARnS A'VD 1�'IITIGATIOI�S The following discussion of potential geologic hazards is based on the geologic, slope, an�l ground water conditions as observed and discussed herein. The discussion will be limited to seismic, landslide, and erosion hazards, including sediment transport. �.0 SLOPE STABILITY HAZARDS AND RECO��1:viENDED MITIGATION Reconnaissance of this site was limited to the area shown on Figure 2. The site topographti is relatively flat, and therefore the risk of landslidi�lg is Ic�«�. 6.0 SEISI�IIC H,�"L.��RDS :�ND RLC0�1�1LI�DED �I1TIG.-�T10:�� Earthquakes occur in the Puget Sound Lowland with great regularity. Most of these events are small and are usually not felt by people. However, large earthquakes do occur, as evidenced b}r the most recent 6.8-magnitude event on February 28, 2001 near Olympia Washington; the 196�, 6.5-magnitude event; and the 1949, 7.2-magnitude event. The 1949 earthquake appears , to have been the largest in this area during recorded history. Evaluation of return rates ��',, indicates that an earthquake of the magninide between 5.5 and 6.0 is likely within a gi��en i 20-year period. Generally, there are four t}'pes of potential geologic hazards associated with large seismic events: 1) surficial ground rupture, 2) seismically induced landslides, 3) liquefaction, and 4) ground motion. The potential for each of these hazards to adversely impact the proposed project is discussed below. I 6.1 Surficial Ground Rupture I The nearest known fault trace to the project site is tlle Seattle Fault, located approximately � 5 miles to the north. Recent studies by the U.S. Geological Survey (USGS; e.g., Johnson et � al., 1994, Origin and Evolution of the Seattle Facclt and Seattle Basirt, Washington, Geology, �I v. 22, pp. 71-74; and Johnson et al., 1999, Active Tectonics of the Seattle Fault and Ceritral : Puget Soccncl Washington - Implicattons for E�trth�ccake HaZards, Geological Society of America Bulletin, July 1999, v. 111, n. 7, pp. 1042-1053) have provided evidence of surficial ground rupture along a northern splay of the Seattle Fault. The recognition of this fault splay is relatively new, and data pertaining to it are limited, with the studies still ongoing. According to the USGS studies, the latest movement of this fault was about 1,100 years ago when about 20 feet of surficial displacement took place. This displacement can presently be seen in the form of raised, �vave-cut beach terraces along Alki Point in VVest Seattle and Deceniber 10. 2009 ASSOCIATED EARTH SCIENCES, LVC IPi�Ih-F;l_!/S!ii9L-i_'-Pn,;i��;l�"(Hl9(1i951i�['V.P Page 6 Scc6su�face Exploratio�t, Geologic Hazard, Rertton Memorial Stadium Additions and Pr•eliminary Geotedtnical Engineering Repa-t Re�ito�i, Waslii�tgto�: Geologic Hazards a►id Mitigatio�is Restoration Point at ttie south end of Bainbridge Island. The recurrence interval of movement along this fault system is still unknown, although it is hypothesized to be in excess of several thousand years. Due to the suspected long recurrence interval and depth of loose/soft alluvium present within the site boundaries, the potential for surficial ground rupture is considered to be low during the expected life of the proposed structure. b.2 Seismically Induced Landslides Reconnaissance of this site was limited to the area shown on Figure 2. The site topography is i-elatively flat to gently sloping, and therefore the risk of landsliding is low. 6.3 Liquefaction ', l�4'e performed a liquefactiori hazai-d analysis for this site iii accordaiice with guideli»e� published in Seed & Idriss, 1982; Seed, et al., 1985; and Kramer, 1996. Our liquefactic�n analysis was completed with the aid of LiquefyPro computer software Version 5 by CivilTe�1� Corporation. Liqiiefaction occurs when vibration or ground shaking associated with moder�� to large earthquakes (generally in excess of Richter magnitude 6) results in loss of inter�:� strerigth in certain types of soil deposits. These deposits generally consist of loose to medi�: dense sand or silry sand that is saturated (e.g., below the water table). Loss of soil stren`��,: can result in cotisolidation and/or lateral spreading of the affeeted deposit with accompanying surface subsidence and/or heaving. The liquefaction potential is dependent on several site-specific factors, such as soil grain size, densit}- (modified to standardize field-obtained values), site geometry, static stresses, level of groui�d acceleration considered, and duration of the everit. The earthquake parameters (a magnitude 7.5 eai•thquake occtirring directly beneath the site with a peak horizontal ground acceleration of 0.35g) used in our liquefaction analysis are in accordance with the required parameters set forth in the 2006 Irtternational Building Code (IBC). Based on the subsurface conditions encountered in our exploration borings EB-1 through EB-4, the estimated amount of liquefaction-induced settlement, through the depths explored, ranges from about 15 to 20 inches during a design-level event. It should be understood that several soil properties used in the liquefaction analysis are estimated based on published data and engineeri�ig judgment. It should also be understood that the alluvium encountered in our explorations extends below the depths explored, and that liquefiable soils may exist at depth. Therefore, these settlement estimates should be considered approximate and "worst-case scenarios" limited to ttie depths explored. In addition to liquefaction settlement, the site soils are also subject to consolidation settlement under the new static building loads (independent of seismic shaking). Therefore, we recommend that all building eiements, iiicluding floor slabs and other structures, be supported on pile foundations. However, if the owner can assume the risk of potential liquefaction-induced settlements of this maQnitude, the floor slab in a lightly loaded, uninhabited D�ce�n6er 10, '009 .9SSOCIATED E.ARTH SCIE,'��CES. I:VC. �n�:;r� f,�noo.;�6,�,-�,��;��,,._o�;yr�:��h,.��i�P Page 7 Substtrface Exploratio�t, Geologic Hazard, Renton Memorial Sradium Additions and Prelinrinary Geotechnical Engineering Report Rerito►i, Washingto�t Geologic Hazards alid Mitigatio�u structure could be supported as a floating slab-on-grade. Pile foutidations that extend to the minimum depths described in the "Design Reconunendations" section of this report should reduce both consolidation settlement and seismically induced structure settlement to tolerable levels for new construction. Partial mitigation of the liquefaction risk could be provided by the use of a structurally reinforced mat foundation. The mat foundation would be subject to total and differential settlements that are considered greater than acceptable. The mat foundation would act as a "raft" below the structure to help reduce structural damage. Post-earthquake re-leveling may or may not be possible or practical, based on the settlement experience. A mat foundation will not mitigate consolidation settlement. We are available to provide more input on a mat foundation system, if requested. 6.4 Ground Motion Guidelines presented in the 2006 IBC should be used for structural design. Based on the exploration borings performed at the site, we interpret the subsurface conditions to correspond to a Site Class "F", as defined by Table 1613.5.2 of the 2006 IBC. Site Class "F" would apply to the site due to the potential for liquefiable soils. However, we ariticipate that the period of ��ib"ration of the structure will be less than 0.5 second, which should be confirmed by the structural engineer. Therefore, we recommend using a Site Class "E" per Note b in Tables 1615.5.3(1} and 1615.5.3(2) of the 2006 IBC and Sections 11.4.7 and 20.3 of ASCE 7. Information presented by the USGS Earthquake Hazards Program indicates a spectral acceleration for the project area for short periods (0.2 seconds) of Ss = 1.438 and for a 1-second period of S� = 0.492. 7.0 EROSION HAZARDS AND MITIGATIONS As of October 1, 2008, the Washington State Department of Ecology (Ecology) Construction Storrn Water General Permit (also known as the National Pollutant Discharge Elimination System [NPDES] permit) requires weekly Temporary Erosion and Sedimentation Control {TESC) inspections and turbidity monitoring of site runoff for all sites 1 or more acres in size that discharge storm water to surface waters of the state. Although we anticipate tliat the proposed project will require disturbance of less than 1 acre, we provide in the following sections recommendations to address these inspection and reporting requirements, shauld tl�ey be triggered. The following sections also include recommendations related to general erosion control and mitigation. The TESC inspections and turbidity monitoring of runoff must be completed by a Certified Erosion and Sediment Cantrol Lead (CESCL,) for ttie duration of the construction. The weekly TESC reports do not need to be sent to Ecology, but should be logged into the project Storm Water Pollution Prevention Plan (SWPPP). Ecology requires a monthly summary report of the Decembe►� 10, 2009 ASSOCIATED EARTH SCIENCES, INC. iPUtb-KL•090396:1'-P�ojecfsl_'lXKJ03961KE�WP Page 8 Sirhs�uface Exploratiart, Geologic Hazard, Re11to�i :Lleuiori�rl Stn�tii+�n Additio��s a�id Pt•eluni�ta�_y Gentechnical Erigi�teeri�tg Report Re�i�o�l, �i'aslii�igraz Geologic Ha�a�-ds and A�itigatio�is tizrbidity monitoring results signed hy the NPDES permit holder. If the monitored turbidity equals or exceeds 25 nepl�elometric turbidity units (NTU) (Ecology benchmark standard), the project best management practices (BMPs) should be modified to decrease the turbidity of storm water leaving the site. Changes and upgrades to the BMPs should be documented in the weekly TESC reports and continued until the weekly turbidity reading is 25 NTiJ or lower. If the monitored turbidity exceeds 250 NTU, the results must be reported to Ecology via phone within 24 hours and corrective actioris should be implemented as soon as possible. Daily turbidity motiitoring is continued until the corrective actions lower the turbidity to below 25 NTU, or until the discharge stops. This description of the sampling benchmarks and reporting requirements is a brief summary of the Canstruction Storm Water General Permit conditions. The general permit is available on the internet'. In order to meet the current Ecology requirements, a properly developed, constructed, and maintained erosion control plan consistent ��ith City of Renton standards and best management erosion control practices will be required for this project. Associated Earth Sciences, Inc. (AESI) is available to assist the project civil engineer in developing site-specific erosion control plans. Based on past experience, it will be necessary to make adjustments and provide additional measures to the TESC plan in order to optimize its effectiveness. IJltimately, the success of the TESC plan depends on a proactive approach to project planriing and contractor implementation and maintenaiice. The most effective erosion control measure is the maintenance of adequate ground cover. Maintaining cover measures atop disturbed ground provides the greatest reduction t� the p�tential gerieration of turbid runoff and sedirnent transport. During the local wet season (October 1" through March 31s`), exposed soil should not remain uncovered for more than 2 days unless it is actively being worked. Ground-cover measures can include erosion control matting, plastic sheeting, stra«� mulch, crushed rock or recycled concrete, or mature hydroseed. Surface drainage control measures are also essential for collecting and controlling the site runoff. Flow paths across slopes should be kept to less than 50 feet in order to reduce the erosion and sediment transport potential of concentrated flo�v. Ditch/s�vale spacing will need to be shortened with increasing slope gradient. Ditches and swales that exceed a gradient of about 7 to 10 percent, depending on their flow length, should have properly constructed check dams installed to reduce the flo«� velocity of the runoff and reduce the erosion potential within the ditch. Flow paths that are required to be constructed on gradients between 10 to 15 percent should be placed in a riprap-lined s�;Jale with the riprap properly sized for the anticipated flow conditions. Flow paths constructed on slope gradients steeper than 15 percent should be placed in a pipe slope drain. AESI is available to assist the project civil engineer in developing a suitable erosion control plan �;�ith proper flow control. ' l�t�p:�';ww�v.ecy.wa.govlpro�runs;�vcLs.�im�vater:construction,'eonstruc[ionlinalpermit.pdf December 10, 2009 ASSOCIATED EARTH SCIENCES, 1:\'C �Pt�rb-r(rov�39�.,�-P;.�ie�;��>rk�Ho;9Fsh�E,�1,P Page 9 Sulistuface Erploratio�t, Geologic Hazard, Reritori Meir�nrial Staditina Additions a�td Preli►r:i►�ary Geotech�iical Engi�ieeriitg Report Re�itai, Washi�zgto�t Geologic Hc�zards artd Mitigatio�is With respect to water quality, having ground cover prior to rain events is one of the most important and effective means to maintain water quality. Once very fine sediment is suspei�ded in water, the settling times of the smallest particles are on the order of weeks and months. Therefore, the typical retention times �f sediment traps or ponds will not reduce the turbidity of highly turbid site runoff to the benchmark turbidity of 25 NTU. Reduction of turbidity from a construction site is almost entirely a function of cover measures and draivage control that have been implemented prior to rain events. Temporary sediment traps and ponds are necessary to control the release rate of the runoff and to provide a catchment for sand-sized and larger soil particles, but are very ineffective at reducing the turbidity of the runoff. Silt fencing should be utilized as buffer protection and not as a flow-control measure. Silt fencing is meant to be placed parallel with topographic coiitours to prevent sediment-laden runoff from leaving a work area or entering a sensitive area. Silt fences should not be placed � to cross contour lines without having separate flo�� control in front of the silt fence. A swale/berm combination should be constructed to provide flow coritrol rather than let the runoff build up behind the silt fence and utilize the silt fence as the flow-control measure. Runoff flowing in front of a silt fence will cause additional erosion and usually will cause a failure of the silt fence. Impi-operly installed silt fencing has tlie potential to cause a much larger erosion hazard than if the silt fence was not installed at all. The use of silt fencing should be limited to protect seiisitive areas, and swales should be used to provide flow control. 7. 1 Erosion Hazard Mitigation To mitigate the erosion hazards and potential for off-site sediment transport, we would recominend the following: 1. Construction activity should be scheduled or phased as much as possible to reduce tlie amount of earthwork activity that is performed during the winter months. 2. The winter performance of a site is dependent on a well-conceived plan far control of site erosion and storm water runoff. It is easier to keep the soil on the ground than to remove it frorn storm water. The owner and the design team should include adequate ground-cover measures, access roads, and staging areas in the project bid to give the selected contractor a workable site. The selected contractor needs to be prepared to implement and maintain the required measures to reduce the amount of exposed ground. A site maintenance plan should be in place in the event storm water turbidity measurements are greater than the Ecology standards. Decembet� 10, 2009 ASSOCIATED EARTH SCIENCES, INC. IPLJtb-KE090396A2-Pro�etrsl?00903961KEIWP Page 10 Substu face Exploration, Geologic Hazard, Renton,�1�Iemor�ial Stndiiun Additions and Prelintinary Geotechnical Engineering Report Re�itora, Washingtori Geologic Hazards mid Mitigatio�is 3. TESC measures for a giveli area to be graded or otherwise worked should be iiistalled soon after ground clearing or timber harvesting. The recommended sequence of constructioii within a given area after clearing/timber harvesting would be to install sediment traps and/or ponds and establish perimeter flow control prior to starting mass grading. 4. During the wetter moiiths of the year, or when large storm events are predicted during the summer months, each work area should be stabilized so that if showers occiir, the work area can receive the rainfall without excessive erosion or sediment transport. The required measures for an area to be "buttoned-up" will depend on the time of year and the duration the area will be left un-worked. During the winter months, areas that are to be left un-worked for more than 2 days should be mulched or covered with plasti� During the summer moiiths, stabilization will usually consist of seal-rolling th� subgrade. Such measures will aid in the contractor's ability to get back into a worl: area after a storm event. The stabilization process also includes establishing temporary storm wrater conveyance channels through work areas to route runoff to the approved treatment facilities. 5. All disturbed areas should be revegetated as soon as possible. If it is outside of the growing season, the disturbed areas should be covered v��ith mulch, as recommended in the erosion control plan. Straw mulch provides a cost-effective cover measure and can be made «-ind-resistant with the application of a tackifier after it is ��lacec3. 6. Sui-face runoff and discharge should be controlled during and follo«�iri� development Uncontrolled discharge may promote erosion and sediment transport. ilnder nc� circumstances should concentrated dischai-ges be allo��ed to tlo�� ovei� the top ��f steep slopes. 7. Soils that are to be reused around the site shoiild be stored in such a man�lel- a; tc� reduce erosion from the stockpile. Protective measures may include, but are not limited to, covering �vith plastic sheeting, the use of low stockpiles in flat areas, or the use of silt fences around pile perimeters. During the period between October 1" and March 31S', these measures are required. 8. Oii-site erosion control inspections a�id turbidity monitoring (if required) should be performed in accordance ��ith Ecology requirements. Weekly and monthly reporting to Ecology should be performed on a regularly scheduled basis. A discussioii of temporary erosion control and site runoff monitoring should be part of the weeklv construction team meetings. Temporary and permanent erosion control and drainage measures should be adjusted and maintained, as necessary, for the duration of project construction. Dece�rrhel•10, 2009 ASSOCIATED EARTH SCIE,tirCES, 1:ti'C ,_ - ,��:��;�. �;��s:_-,�,.-.-� =,.n;v,;:>�-;._L��,,�� Page 11 Stibscuface Exploratioli, Geologic Hazard, Reiuu�t �'�lentorinl Stadium Additioiis aiid Prelimi�iary Geotech�iical Engi�teering Report Renton, Washington Geologic Hazards and Mitigatiais It is our opinion that with the proper implementation of the TESC plans and by field-adjusting appropriate mitigation elements (BMPs) throughout construction, as recommended by the erosion control inspector, the potential adverse impacts from erosion hazards on the pro.ject may be mitigated. December 10, 2009 ASSOCIATED EARTH SCIENCES, INC. IPl.4b-KL-09039�A'-Pro�errs�'0090�96iKEll�'P Page 12 Suhscuface�tploratio�i, Geologic Hazard, Renton:tilenrorial Stadilun Additions and Prelijninarv Geotechnical Engineering Report Renton, �t'ashington Prelintinan�Design Recanmendarions III. PRELIMINARY DESIGN RECOMMEI�ATIONS 8.0 INTRODUCIION The site contains some potential soil and foundation-oriented complications with respect to compressible soils, loose granular soils susceptible to liquefaction, and moisture- and disturbance-sensitive soils. The conclusions and recommendations in this report are based upon the assumption that the foundations, floor slab, and grading construction are obser�Ted by a geotechnical engineer or engineering geologist from our firm. The proposed project is feasible from a geotechnical engineering standpoint using pile foundations for the building superstructure, and pile-supported lower floor slabs except where the owner can tolerate the risk of liquefaction-induced settlements during a design level earthquake event. Buildings and floor slabs that will be inhabited or that store hazardous i�laterials should be pile-supported. Loose surficial fill and native soils should not be used to �upport planned foundations. If any of the floor slabs will be "floated," they should be eonstructed on a minimum of 2 feet of approved structural fill compacted to 95 percent of ��STiV1:D 1557. Pavement or hardscaping support on existing soils is possible with some near- surface remedial improvements. Due to the possible presence of loose surficial soils, liquefaction hazards, and/or consolidation settlement, some settlement of non-pile-supported structures and paved areas, however, is anticipated. As mentioned previously, a structural mat foundation may be an alternative to a fully pile-supported structure, provided the risks of some post-construction consolidation settlement and possibl_y significant liquefaction-induced settlement can be accepted. Vb'e are available to discuss a mat foundation. if requested. 9.0 SITE PREPARATION Site preparation of planned building and road/parking areas that will not be supported by pile foundations should include removal of all existing buildings, foundation elements, utilities, a�phalt, landscaping, debris, and ariy other surficial deleterious material that are not part of the planned project. Additionally, any upper organic topsoil encountered should be removed and the remaining roots grubbed. Areas where loose surficial soils exist due to demolition or stripping/grubbing operations should be considered as fill to the depth of disturbance and treated as subsequently recommended for structural fill placement. The fill ericountered in our explorations was generally in a loose condition. However, the density, thickness, and content of the fill across the site may be highly variable. We anticipate that any upper loose surficial �11 soils, once recompacted or replaced with structural fill, will be adequate for support of pavement and other external surfacing, such as sidewalks or segmented paving units. However, there will be a risk of long-term damage to these surfaces Decentber 10, 2009 ASSOCIATED EARTH SCIENCES, l,tiC. lPL/rb-KE090396-I'-Pro,�c-:rs�'�903961KE'�ti-P Page 13 St�bscufar.e Explor�atio�i, Geologic Ha<.�rd, Reftton A�lemorinl Stadirnn Additions and Preliminary Geotechnical Engineering Report Rentori, 4�'ashington Preli�nina»�Desigr� Recommendariolis inclu�ing, but not limited to, rutting, yielding, cracking, etc., if any uncontrolled loose fill or surficial loose soil is iiot completely removed and replaced with compacted structural fill. The risk can be reduced by selective removal and replacement of the most settlement-sensitive, near-surface soils. Utilities founded above loose, uncontrolled fill are also at risk of settlement and associated damage. The extent of strippi�ig necessary in areas of the site to receive external surfacing, such as sidewalks and pavement, can best be determined in the field by the geotechnical engineer or engineering geologist. We recommend proof-rolling road and parking areas with a loaded tandem-axle dump truck to identify any soft spots. If coiistruction is to proceed during wet weather, we recommend systematic probing in place of proof-rolling to identify soft areas of the exposed subgrade. These soft areas should be overexcavated and backfilled with structural fill. Some of the on-site fill and surface soils contain a high percentage of fine-grained material, which makes them moisture-sensitive and subject to disturbance when wet. The contractor must use care during site preparation and excavation operations so that the underlying soils are not softened. If disturbance occurs, the softened soils should be removed and the area broiight I, to grade with structura] fill. If the existing pavement will not be used for access and staging '', areas, consideration should be given to protecting access and staging areas with an appropriate section of crushecl rock or asphalt treated base (ATB). The existing pavement is in such poor condition that it may be necessary to augment the pavement with ATB if it will be used for construction access and staging. If crushed rock is considered for the access and staging areas, it should be underlain by ' engineering stabilization fabric to reduce the potential of fine-grained materials pumping up through the rock and turning the area to mud. The fabric will also aid in supporting construction equipment, thus reducing the amount of crushed rock required. We recommend that at least 10 inches of rock be placed over the fabric; however, due to the variable nature of ' the near-surface soils and differences in wheel loads, this thickness may have to be adjusted by the contractor in the field. 10.0 STRUCTURAL FILL All references to structural fill in this report refer to subgrade preparation, fill type aiid placement, and compaction of materials, as discussed in this section. If a percentage of compaction is specified under another section of this report, the value given in that section should be used. After stripping, planned excavation, and any required overexcavation have beeli performed to the satisfaction of the geotechriical engineer, the upper 12 iiiches of exposed ground in areas to Decentber 10, 2009 ASSOCIATED EARTH SCIENCES, INC JPI.r'rb- KL•fi9(i79,q?-P.�ulerl�130090.i961KE�6b�P P3�TE 1'� Sctbsurface Ezploratio�2, Geologic Hnzard, Rentoii Memorial Stadiiu�i Additions mid Preli�riinary Geotedrr2ical Ei:girieerir:g Report Reiuon, Washi�igto�i Preli►ninary Desigrt Recomme��datioris receive fill should be recompacted to 90 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. If the subgrade contains silty soils and too much moisture, adequate recompaction may be difficult or impossible to obtain and should probably not be attempted. In lieu of recompaction, the area to receive fill should be blanketed with washed rock or quarry spalls to act as a capillary break between the new fill and the wet subgrade. VVhere the exposed ground remains soft and further overexcavation is impractical, � placement of an engineering stabilization fabric may be necessary to pre�rent contamination of the free-draining layer by silt migration from belo��. After recompaction of the expose� ground is tested and approved, or a free-draining rock , course is laid, structural fill may be placed to attain desired grades. Structural fill is defined as ' non-organic soil, acceptable to the geotechnical engineer, placed in maxirnum 8-inch loose lifts, with each lift being compacted to 95 percent of the modified Proctor maximum density using ASTM:D 15�7 as the standard. In the case of roadway and utility trench filling, the backfill should be placed and compacted in accordance with current local codes and standards. The top of the compacted fill should extend horizontally out��ard a minimum distance of 3 feet beyond the location �f the road«�av ed�es hefore sloping d��vn at an angle of 2H: 1�- (Horizontal:Vertical�. The contractor should note that an}� proposed fill soils must be evaluated by AESI prior to their use in fills. This would require that we have a sample of the material 72 hours in advance to perform a Proctor test and determine its field compaction standard. Soils in which the amount of fine-grained material (smaller than the No. 200 sieve) is greater than approximatel} 5 percent (measured on the minus No. 4 sieve size) should be considered moisture-sensitive. [1se of moisture-sensitive soil in structural fills shovld be lunited to favorable dry weather conditiocis. The on-site soils generally contained significant amounts of silt and are considered very moisture-sensitive. In additioi�, constructioi� equipment traversing the site when the soils are wet can cause considerable disturbance. If fill is placed during wet weather or if proper compaction cannot be obtained, a select import material consisting of a cleati, free-draining gravel and/or sand should be used. Free-draining fill consists of non-organic soil �vith the amount of fine-grai�ied material limited to 5 percent by weight when measured on the minus No. 4 sieve fraction with at least 25 percent retained on the No. 4 sieve. A representative from our firm should inspect the stripped subgrade and be present during placement of structural fill to observe the work and perform a representative number of ii�- place density tests. In this way, the adequacy of the earthwork may be evaluated as filling progresses and any problem areas may be corrected at that time. It is important to understand that taking random compaction tests on a part-time basis will not assure uniformity or acceptable performance of a fill. As such, we are a��ailable to aid the owner in developing a suitable monitoring and testing program. Decemher 10, 2009 .4SSOCIATED EARTH SCIE,'�'CES, I:VC. !PL%�b-KE090396�1'-Pro;rcrsi?0(i9bj96�KE�li�P �age 1 S SiitlSi[1fQCC EXpIOYRtlOTI, Geologic Hazard, Re�tto�t Memnrial Stadir�m Additions mid Preliminary Geotechnical Engineeri�ig Repor-t Reruon, WQSj1112gl012 Prelimina�y Design Recommendatiw�s 11.0 FOUNDATIONS To mitigate post-construction consolidation settlement and the effects of seismically induced liquefaction, a pile foundation system is recoinmended. For this project, we recommend the use af 18- or 24-inch-diameter augercast piles. Tlie project structural engineer has asked that «�e also provide recommendations for the use of micropiles (for low-headroom installatiori) and pipe piles (for rtioderately-loaded strizctures). The following sections provide pile recommendations based on assumed loading conditions and soils encountered beneath the site. 11.1 Augercast Piles We recommend that the construction of piles be accomplished by a contractor experienced in their installation. Fill soils can have cancrete, brick, wood, and other demolition waste in them, and soi(s of alluvial origin may have gravel lenses or large cobbles present in them. 1t may be necessary to have a backlioe present during pile installation to dig out obstacles and backfill the excavation prior to drilling piling. If obstacles are encountered at depths where removal with a backhoe is not feasible, it might be necessary to modify the pile layout to replace piles that cannot be completed according to the original design. Observation of pile installation by AESI is important to verify that the subsurface conditions observed at pile locations are consistent with the observations in our subsurface explorations, and consistent with assumptions made during preparation of the recommendations in this report. The City of Renton will likely require such inspections of foundation piles. The augercast piles will gain support from end bearing and skin friction. Augercast piles are formed by drilling to the required depth with a continuous flight, hollow-stem auger. Fluid grout is then piimped down tlie hollow stem iinder pressure as the auger is withdrawn. Appropriately desigiied reinforciiig steel cages are then lowered into the unset grout. A single reinforcing bar is installed for the full length of the pile for transfer of uplift loads. Since the grout is placed under pressure, actual grout volumes used are typically 15 to 50 percent greater than the theoretical volurne of the pile. Actual grout volumes for piles constructed through some types of fill and peat can be much more. The pile contractor should be required to provide a pressure gauge and a calibrated pump stroke counter so that the actual grout volizme for each pile can be determined. Typically, a nine-sack, minimum 4,000 pounds per square inch (psi) grout mix is used for augercast piles. Once coiriplete, the piles would then coruiect to a pile cap and grade beam support systern for the building foundation. Typical allowable capacities for the augercast piles are given in Table 1. Development of the design capacities presented in Table 1 requires a minimum overall pile length which extei�ds 5 feet into the bearing layer encountered at EB-1 and EB-2 between 49 and 57 feet depth. Decemher 10, 2009 ASSOCIATED EARTH SCIENCES, INC. JPL/rb-KE09�396A3-Pro�ectsll(l0903961KEI WP Page 16 Subsu�face Exploration, Geologic Hazard, Re�iton Memorial Stadiitnt Additioris a�id Preliminaiy Geotech�tical Engi�:eeri�ig Report Rento►i, Wasltington Preliminary Design Recontmendations Allowable design axial compressive loads may be increased by one-third for short-term wind or seismic loading. Anticipated settlement of the pile-supported foundations will generally be on the order of 'h inch. TaUle 1 Augercast Pile Recommendations Vertical Estimated Compressive Lateral Depth of Pile Diameter Length Capacity Capacit�� fixity Ilplift Capacity (inches) (feet)�'' (tons) (tons)�'-' (feet)�3' (tons)'" 18 54 50 10 14 15 24 �4 80 10 17 20 � "' Pile length based on EB-1 and EB-2 for bearing layer occurring between 49 and 57 feet depth. Bearin� layer encountered at 43 feet in EB-3, but was not used for design. ''-' Allowable lateral capacities are for fixed-headed conditions (incorporation into pile caps and grade beam system), and '/z inch of deflection at the ground surface. Greater lateral capacities are possih]e for greater allowable detlections. "' Tlle depth of tixity does not include the code-required 20 percent increase for reinforcina cage design. 'a' liplift capacity is based on minimum pile ]en��h ��t �4 i�eet. Pile� �ti�ith latei-al �pacing less than 6 pile diameters from another pile along the direction c�f� force should be co�isidered to be iri the zone of influence and the lateral capacity and the reductioii factors presented below should be used. If the lateral contribution of the piles is more critical to the practical design of the structure, we can provide a comprehensive lateral pile analysis. Such an anal�sis wot�ld present lateral pile capacities taking into accaiirit the interaction bet«teen piles. Based on the loose conditions of the soils through which the augercast piles are to he excavated, care should be taken in construction planning to allow grout time to set prior to drilling adjacent piles. Typically, 24 hours of set time is recommended for piles closer than � pile diameters or 10 feet, whichever is greater. The 24 hours can be reduced for adjacent piles drilled on different workdavs. 11.2 Group Effects Where piles are installed in groups and subject to lateral loading, reductions in lateral capacity to account for group effects should be included in design. The effects of group performance should be considered where piles are spaced closer than 6 pile diameters center-to-center and are aligned iri the direction of loading. Piles should not be spaced closer than 3 pi(e diameters December 10, 2009 ASSOCIATED E.9RTH SCIENCES, IA'C. ;PL.tb-KL-090396�1'-Proiecrs!'0090396.KE�:4� Page 17 Subsurface �ploration, Geologic Hazu�� Reliro�i Memorial Stadi«r1i Additio�is a�id Preliminarv Geotechnical Engi�ieeri�tg Rep� Rerito�i, Wasl2i�igta2 Prelimi�iary Design Recomnteridatic� I center-to-center to achieve full vertical and uplift capacity. If piles are staggered II spacing, the tollowing spac:ing and reduction factors presented in Table 2 should apply. I I last pile in a row can be assumed to develop the full lateral capacity. Table 2 Lateral Reduction Factors Pile Spacing Reduction Factor 6 diameters 1.0 5 diameters 0.8 4 diameters 0.6 3 diameters 0.4 11.3 Passive Resistaiice and Friction Factors Lateral loads can be resisted by friction between the pile caps and grade beams and the existing fill soils or structural fill, or by passive earth pressure acting on the buried portions of these elements. The foundations must be backfilled with structural fill and compacted to at least 95 percent of the maximum dry densiry to achieve the passive resistance provided belo��. We recommend the follo��iilg allowable design parameters: • Passive equivalent fluid = 200 pounds per cubic foot (pc� � Coefficient of friction = 0.30 11.4 I��licropiles Micropiles are drilled and grouted reinforced piles typically having a diameter of 6 to 8 inches. They are mainly used as pressure-grouted friction piles to take tension and/or compression loads. The increasing popularity of micropiles stems from the combination of relatively small drilliiig equipment used for placement, allowing installation under lirtiited-access and low-headroom conditions, and relatively high uplift and compression capacities that result from pressure grouting. Some systems use rotary-boring techniques only, rather than heavy percussioii and pile-driving methods, thus reducing the risk of structural damage due to vibrations for installations inside or in close proximity to existing buildings. Several pile t_ypes and reinforcing systems are available. Dece�nber 10, 2009 ASSOCIATED EARTH SCIENCES, IIVC IPL�ib-KE090.396A1-P�o;errs130G90396�KEiu'P Page 1� Scibsurface�zploratio�i, Geologic Hnzard, Rer:toji ,'llenaor-ial Stadiinn Adrlitio�is a�ld Pr�elimiazary Geoteclt�tical E�tgineerirzg Report Rerito�i, �l�asl�ingro�i Preliminary Desig��Recomnae►idatio�is Ttie Ge�vi pile system consists of pile installation t�sing oPen- or cased-hole drilling methods aiid a threaded bar (Gewi Bar) as the reinforcing element. In order to increase the grout to soil bond capacity of the pile, especially in cohesive soils, post-grout tubes are installed at the outer perimeter of the grout body and secondary pressure grouting is repeated until the required pressure or skin friction is achieved. From a geotechnical standpoint, there is no particular advantage to one micropile type versus another for this site. Decisions regarding the micropile system to be used for the site should include cost, availability of qualified micropile contractor «�ithin project schedule/time-frame, ease of installation, and other development-related factors. Based on the subsurface strata encountered at the site, it is our opinion that the proposed micropiles would gain support from skin friction and would be capable of providing resistarice against both uplift and compressive forces. The piles ��ould provide sui�_:i�i� ��Ti�� i��.�.n�� anchors for resisting uplift loads, includin�� _ For 6- or 8-inch-diameter micropiles, ��. :,��:, .� �.i.�_.� .<::� ��:;�� ;�� ;��a«� � _,.:��;_ � pressure grouting as described above, a presumptive allowable `grout-to-ground" skin fricti: of 3,000 psf may be tised for the portion of the micropile embedded within a "load zone" dense, granular soils. Based on our explorations, we estimate that this load zone occurs between 49 and 57 feet below the existing grouiid surface. We recommend a minimum load zone embedment of 5 feet, resulting in a total micropile depth ranging between 54 and 57 feet below the existing ground surface. We recommend a minimum spacing of 5 feet center-to- center on the micropiles. The allo��able skin friction mentioned above may be used for both uplift (tension) and compression loading. AESI is available to provide additional design recoinmendations for specific micropile loading configurations. The allowable skin friction is based on information obtained during our field exploration program and should be confirmed by installation of test piles and field-load testing. Prior to production micropile installation, a sacrificial micropile should be installed in the vicinity of the proposed piles using the same methods and procedures and to the same depth as the production piles. The sacrificial pile shotild be verification-tested in tension to 200 perceiit of maximum allowable seismic design load. Upon successful completion of the verification test, production micropile installation may begin. At least S percent of the production micropiles should be proof-tested to 125 percent of the static design load. 11.5 Pipe Piles a deep foundation s}�stem consisting of small-diameter driven steel pipe piles is acceptable for fouridation support where foundation loads are low to moderate. Pipe piles may consist of 6- inch-diameter pipe. The IBC recommends a maximum pile length of 30 diameters unless engineering judgment allows for modifications to this limitation based on site-specific soii Dece��iber 10, 2009 ASSOCIATED EARTH SCIENCES, 1,'�'C lPLitb-KE090396A_'-Projecrs',�q090196��KL-�RP Page 19 Subsuiface F,xploration, Geologic Ha�ard, Rertto�i Meniorial Stadii�m Additio�is and Prelimirrary Geotechnical Engineer-irig Report Rentoli, Sd�ashi�igto�i Preliminary Desig�z Recommer��tations COIIC�IilOI1S, I�llllCjlll� type, and pile type. For a 6-incli-diameter pile, 30D equates to a maximum pile length of 15 feet. However, the pile depths anticipated for this project range up to 60 feet. In our opinion, 60-foot-long, 6-inch-diameter piles should perform adequately in compression provided the piles will not be expected to support greater column loads than 2� kips, as we have assumed. The soil conditions encountered in our explorations will provide adequate confinement of the piles (even during a period of partial soil column liquefaction) so that "slenderness" is tiot considered a significant design issue. The piles should be galvanized steel pipe, driven with a suitable hydraulic hammer to the refusal criterion shown in Table 4. The following table provides required minimum hammer weights, refusal criterion, and allowable loads for pipe piles. Based on our explorations, pile lengths are estimated to be between 50 and 60 feet below the existing ground surface. Actual driven leugths are unpredictable and may be longer or shorter than the estimated range. Depending on tl�e required foundation loads and equipment access, larger-diameter driven piling may also be used. AESI should be contacted for design recommendations if driven piling greater than 6 inches in diameter �vill be used. Table 4 Pipe Pile Design Parameters Pipe Minimum Refusal Allowable Diameter VVall Hammer Size Criterion"� Load�'� (inches) Thickness (lbs) (seconds) (kips) 6 Schedule 40 1,500 15 20 �; - - -- ---- '�'Refusal is deiined as less than 1 inch of penetration in "X" seconds under constant driving. '''Allowable load for 6-incll-diameter piles to be verified by load tests in accordance with AST'�4�D 1145 "quick load tes�.'� Anticipated settlernent of pipe pile-supported foundations should be less than '/z inch. Pile installation must be observed by AESI to verify that the design bearing capacity of the piles has been attaitied and that construction conforms to the recommendations contained herein. The City of Renton may also reqiiire such inspections. Lateral resistance can be derived from passive soil resistance against the buried partion of the foundation (i.e., the grade beam) or from the installation of batter piles. A passive equivalent fluid of 200 pounds per cubic foot (pc� can be used to account for lateral resistance. Lateral resistance for batter piles should be taken as the horizontal comporient of the axial pile load. Batter piles are typically installed at 1H:4V iiiclination. Decentber 10, 2009 ASSOCIATED EARTH SCIENCES, INC. JPUtb-KE090396A'-Projecrs1300903961K£IWP Page 20 Sttbsu�face Etploratio�t, Geologic Ha;.ard, Rentoir�'I�Ie))101'1Q1 StQCIlIfl17 ACICil110115 nnd Preliminary Geotechnical Engirieering Report Reltton, Washington Preliminary Design Recomrnendations 12.0 FLOOR SUPPORT As discussed earlier in this report, existing site soils are considered to be settlement-prone, and «-e therefore recommend that floor slabs be designed as structural slabs and supported on pile foundations. Where potentially large-scale, liquefaction-induced settlement caii be tolerated, site soils can be used to support slab-on-grade floors, sidewalks, or other similar structures contingent upon adequate remedial preparation and understanding of uncertainties in settlement performance. Slabs, pavement, or segmented paving stones to be supported on grade should be supported oti a 2-foot-thick structural fill mat. All fill beneath slabs, paving stones, or pavement must be compacted to at least 95 percent of ASTM:D 1557. The floor slabs should be cast atop a minimum of 4 inches of clean «-ashed crushed rock or pea gravel to act as a capillary break. Areas of subgrade that are disturbed (loosened) during construction should be compacted to a non-yielding condition prior to placement of capillary break material. It should also be protected from dampness by an impervious moisture barrier at least 10 mils thick. The impervious barrier should be placed between the capillary break material and the concrete slab. 13.0 DILAIN:�GE CONSIDERATIONS All exterior grade beams should be provided with a drain at least 12 inches below the base of the adjacent interior slab elevation. Drains should consist of rigid, perforated, polyvinyl ctiloride (PVC) pipe surrounded by «�ashed pea gravel. The drains should be constructed with sufficient gradient to allow gravity discharge away from the building. Roof and surface runoff should not discharge into the footing drain system, but should be handled by a separate, rigid, tiglitline drain. In planning, exterior grades adjacent to walls should be sloped do��m��ard a«a�� fi-om the structure to achieve surface drainage. 14.0 PAVEIv1ENT RECOMMENDATIONS The majority of the parking and access areas are plaiined for ttiose portions of the site underlain by fill materials overlying looselsoft soils. Therefore, some remedial measures ma} be necessary for support of new pavemei�t or for areas of hardscaping (e.g., paving stones). To reduce the depth of overexcavatioii required and to achieve a suitable subgrade for support of tlie pavement, we recommend that an engineering stabilization fabric or geogrid reinforcement be placed over the stripped subgrade prior to filling. The addition of an engineering stabilization fabric or geogrids permit heavier traffic over soft subgrade and increases the service life of the system. The fabric acts as a separation barrier between relatively fine-grained surficial materiais on the site and the load-distributing aggregate (sand or crushed rock). As a separator, it reduces the loss of costly aggregate material into the subgrade and prevents the upward pumping of contarninating silt into the aggregate. The high Dece�riber 10, 2009 ASSOCIATED EARTH SCIENCES, I��'C. .lPi-r6-';E0�39��13-P�o;��,��si_'Gfi92�96�f:Elb1'P Pc"l�e �1 __ _ Si�bstuface Etploratto�i, Geologic Hazard, Reittat Memorial Stadiuni Additions a�td Pr-eli►tii�iary Geotechnical Engi►:eering Reporr Re�ttai, Waslti�2gto�i P�-elinti�tarv Design Reconune�idatio�is tensile strength and low modulus of elongation of the fabric also act to reduce localized stress by redistributing traffic loads over a wider area of subgrade. In addition, the recommended method of installation (proof-rollirig) identifies �veak areas, which can be improved prior to paving. After the area to be paved is stripped and recompacted to the extent possible, engineerin� stabilization fabric, such as AMOCO 2002 (or equivalent), should be placed over the subgrade with the edges overlapped in accordance with the manufacturer's recommendations. Following subgrade preparation, clean, free-draining structural fill should be placed over the fabric and compacted to 95 percent of ASTM:D 1557. Where fabric is exposed, spreading should be performed such that the dozer remains on the fill material and is not allowed to operate on uncovered fabric. When 12 inches of fill has been placed, the fabric should be proof-rolled with a loaded dump truck to pretension ttie fabric and identify soft spots in the fill. Upon completing the proof-rolling operation, additional structural fill should be placed and compacted to attain desired grades. Upoci completion of the structural fill, a pavement section consisting of 4 inches of asphalt concrete paverrieiit (ACP) underlain by 2 incties of S/s-inch crushed surfacing top course and 6 inches of 1 '/a-inch crushed surfacing base course is the recommended minimum. The ci-ushed rock courses rnust be compacted to 95 percent of maximum density. Given ihe potentially variable in-place density of the existing fill subgrade, some settlement of paved areas should be anticipated unless the existinQ fill is entirely removed and replaced with structural fill. � 1�.0 PROJECT DESIGN AVD CONSTRUCTION i�10NITORING At the time of this report, site grading, structural plans, and construction methods have not been completely finalized. We are available to provide additional geotechnical consultation as the project design develops and possibly changes from that upon which this report is based. We recommend that AESI perform a geotechnical review of the plans prior to final design completion. In this way, our earthwork and foundation reconunendations may be properly interpreted and implemented in the design. We are also available to provide geotechnical engineering and monitoring services during construction. The integrity of the pile foundation system depends on proper site preparation and construction procedures. In addition, engineering decisions may have to be made in the field in the event that variations in subsurface conditions become apparent. Construction monitoring services are not part of this current scope of work. If these services are desired, please let us know, and we will prepare a cost proposal. December 10, 2009 ASSOCIATED EARTH SCIENCES, INC. JP1./ib-KE090?96:1?-Pro�ectsl?OiD903961KE1WP Page 22 Sicbs«�face Exploration. Geologic Hazard, Reiiron Memor�ial Stadium Additioiis ar�d Pl•eliminary Geotedinical E�zgilteerirzg Repo�-t Re�itori, Waslii�tgtott Prelimi�tary Design Recanmendatio�is We have enjoyed working with you on this study and are confident that these recomrriendations �vill aid in the successful completion of your project. If you should have any questions or require further assistance, please do not hesitate to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. I�irkland, VVashington ,� p. M q"�.�i ,�.yJe' �,s v.la'��i'��4�a <� ;�:L,,' 1��^ �` + ��` ;�:1�.,� -c , -�,% "� �'l.� 4 �G;�1 C t _ � / /` / � :�n��`��/A�(cE� �✓ 15� � ` �s�/,�� "��!�N�A�� Jeffrey P. Laub, P.G., P.E.G. Kurt D. Merriman, P.F,. Project Engineering Geologist Principal Engii�eer Attachments: Figure 1: Vicinity Map Figure 2: Site and Exploration Plan Appendix: Exploration Logs December 10, 2009 ASSOCIATED EARTH SC161VCES, L�'C. JPL/tb-KE090396Ad-Projecrsl?009p396tKEIWP Page 23 � 1 .,, ��`�.6. rsr.o 26 - . . �� . �.. '�� ,� . �� ,' Nf �� v i � 1 \ . :� � .'`�.�� _.� \-�,� �,�. � / :..�� Z �' �` `g � \.- ;��. T N ,: . A •� ,,; I � � �� p � fOqtbid�C�� i � �-- � .�J � ) � _ `�` _`�_� `,�� ,I ` _ ` � ' POW9t �J � 1� ` ,� ,� J �� _`,p,. ! � �� _4 •• _ 7 • �., -�'+� ,�. ��E" �" O!' 1' � �' � O �! ��a , 1 _ s � t � �j'_ 7�", �, TER N E !'f:- Pk� � l .S: • "�,��-�"�t �_� � '•�� ` � ��'� *"� ?!� $ . � `� \ `! 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'- [-- . � ..� ' . I -_.. r u-_- -- :. _, _m _. � � - - - -. . ._. ..,, - - - - -- - - -S - - ' ' I -i.._. � ��o � �.. . _ . t � • , -�3~_�. �- - - - -- � _ -��XISTIHG LONG JUP.4P AREAS. l-� - ; . �`�,\ _ - - . ' �' _ ' ' — ___�_ __ _ _' _ ! I ! i__� ! -1"?�'"_�'-f_ _f_'__-,-_ _ _. ..__ /� :T \. .. ' ...'1 O �, . . 1�� r: ; , I oz ` o z ae i o 0 o�s } . o o,c olz � ol� � ..�, \ � ; � � � . i i -_.- - , . � . . _ . . . . . . -i. , . � ,. . . � 1 , � -. .-, . . �, ;� '� , � i � � i ; � � � , ;;: � ' . . _ � _ �.p �! • � I � I I I i I � ' l �, !�' _ -. :r. -...u,r .. . . - . -}i. • . . u a � I � I � ; Ij ! ' t ' I�� V i f � I +� -'i`-._ . � -.. ��-_ =k- !�.'.� -t .. ..- . ' I . � ..L � 1 ! 1 � _' __ _ f- I_ � I ,.�..�i ._�._.I - :,.... '� 1�': .. ��'� � . . . . .i,�'= - "_� t._ . � �, �;..::;�- - � � � 1 , F � � � i r {- � _� -, � -.;� _): `. _i _, - : ,,...., _ _ . . . i i .. ....... , _� � � t ; � ,_ i _ . '.. 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" ---1.�i _ .. 1 -'_'- ' - ` \_ _ /., � �', - _= - - - _ ;: _ --� -_ - _- .1 - � � . , . . „ ,. _ _ _ . � - - - � - - - _ , - - - - _ - _ - �_ ... - - - -- -- - ; _-- - - =--=-�- - _ - - -- - __ - -_ -=--.-:-i� ; -_,_ - .. .,.._ , _ _ _ __ _ _ - -- -- -- --- - -- . _ .5. _ __ � _ ___. _ , 1 . ------= ----- - .�--�_ -- — — - -- � _, . , � • }' �___•'"� \�� j .� . -�_. --� - - � - � � - - r ' �� .-- -_=� ' i � � � a , - ... .EB'2 •± --- --- � -� -------'----1 ,� � - -- �� . �EB'� -�ec � _. . _ u`ii .. ,... Q .-� .-; . _ .,r . --t _ ..- - - - - - - - - _ ._ �. - x : - - w . � ' , - _-___ .- .. . , ' _. . . � _ . f _ ___--? � -_. . . , m ` + ' ` _ _��_" � , - - - - - �aai��sTaacun� ' � ' N � .. �,�.�� , - . . _._ .. �-- � �_.. . � ----- -- 801LER ROOh1 Q� A , ._ .. . .. i. , .- � � --$.TICKET 800TH oa . . � .- . . . . ^ � i _. ._ _ . . _ , . �o ? - , " .. ` ' - - ------- - ' 0 40 80 a 3 � REFERENCE: LPN FEET a e m - � Associated Earth Sciences, Inc. SITE AND EXPLORATION PLAN FIGURE 2 0 � m � a � ❑ � :�_� RENTON MEMORIAL STADIUM DATE 11l09 RENTON, WASHINGTON a PROJ.NO. KE090396A � M� A Z W a a � � `o � Well-graded gravel and Terms Describing Relative Density and Consistency @ � o°o° GW gravel with sand, little to Density SPT�z�blows/foot � � °o G no iines Very Loose 0 to 4 � � > \o°o°o Coarse- �oose 4 to 10 o o Poorl y-graded gravel Grained Soils M e d i u m D e n s e 1 0 t o 3 0 � � � `"'�o 0 0 o GP and ravel with sand, Tes t Sym bo ls o � � lo�o°o 9 Dense 30 to 50 0 0 0 o o 0 0 little to no fines Very Dense >50 G =Grain Size N o z °o°o° �2� M =Maisture Content Z o o , d, o i Consistency SPT blowslfoot A=Atterberg Limits � � �N Silty gravel and silty Very Soft 0 to 2 C=Chemical 0 1° °'�- ' ° ° GM gravel with sand Fine- Soft 2 to 4 DD= Dry Density t c ,�i � � � � , 0, 0 Grained Soils M e d i u m S li i f 4 t o 8 K= P e r m e a b i l i t y c o a� � � � � o Stiff 8 to 15 � � " Clayey gravel and very Stiff 15 to 30 � � N� G� clayey gravel with sand Hard >30 � � Component Definitions L o 17Vell-graded sand and Descriptive Term Size Range and Sieve Number � �� :: gyy sand with gravel,little Boulders Larger than 12" � `O �,;:�:�:�:�:� to no fines Cobbles 3"to 12" � �. a� 'u. ::;:;::::: y Gravel 3"to No 4(4 75 mm) �' � a� ; Poorly-graded sand Coarse Gravel 3"to 3/4" in �j � �� SP and Sand with gravel, Fine Gravel 3/4"to No 4(4 75 mm) m a v ; little to no fines � „ Sand No 4(4 75 mm)to No.200(0 075 mm} � � z Coarse Sand No.4(4.75 mm)to No 1 Q(2 00 mm) �; � °N' � � SM Silty sand and Medium Sand No 10(2 00 mm)to No 40(0 425 mm) � � s i l t y s a n d w i t h F i n e S a n d N o 4 0(0 4 2 5 m m)t o N o 2 0 0(0 0 7 5 m r r) Uo a LL � gravel Silt and Clay Smaller than No 200(0 075 mm) � � � Sc Clayey sand and �'>Estimated Percentage Moisture Content � N� clayey sand with gravel Dr Absence of moi=ture, � Percentage b� y� �' Component �/eight dus!y,dry.o the touch I I Trace <5 Slightly Moist-Perceptible Silt, sandy silt. gravelly silt, �, o M� silt with sand or gravel Few 5 to to moisture � � Little 15 to 25 Moist-Damp but no visible u� ,n L With -Non-primary coarse waier oU N %% CI3y of low to medium constituents: > 15% Very Moist-Water visible but o � � � C� plasiicity. silty, sandy:or -Fines content between noi free draining Z � = /� gravelly Clay, lean clay �°�and 15% VJei-Visible free v�ater,usually � � � � � from below waier table a � � �=� Organic r.lay or silt of low Symbols a� � _= oL plasticiry Blows/s•or � Sampler ortion of 6" ;� � __ P � Cemen,groul Type / ��su�tace seal ° Elastic sil#, clayey silt,silt � / Sampler Ty�e � '� o with micaceous or 2� `�� ''�io��z Description o � MH Splii-Sp�D� „ seal �n o diatomaceaus fine sand or Sampler i 3 0"OD Split-Spoon Sampler - =ilter pack w�th _N �o Silt (SPT} -� 3�5"OD Split-Spoon Ring Sampl2r �.1� �lank casing � v o � + Clay of high plastiCity, : cection a � �' � sand or ravelf da ,fat Bulk samF e - � c -= r � CH y g Y y 3 0' OD Thin-Wall Tube Sampler - 5creened casin9 � �D � � CI8 with sand or ravel I' .'or Hydro[ip � y Y 9 .!. p�c!uding Shelby lube} � � :with iiller pack � — � Grab Sample ,�� _ � � , �".�.;, -; .- End cap c � ;�;;�;, Organic clay or silt of � Portion not recovered `� �' ;;;; oH medium to high �,� �,� i,i Perceniage by dry weight De th of round water ��;�i� plastiCity !2} (SP�Standard Penetration Test P 9 ..i�i 1 ATD=At time of drilling (ASTM D-1586) L7 Static water level;date) >,.� N `"'`'"" Peat, muck and other 13� In General Accordance with o� Q,�o �� PT highly organiC soils Standard Practice for Description �5� Combined USCS symbols used for = O and Iden;i`ication of Soils(ASTM D-2488) fines between 5%and 1596 N � � Classifications of soils in this report are based on visual field andlor laboratory observalions,which include density/consistency,moistuie condiiion,grain size,and � plasticiry estimates and should not be construed to imply field or taboratory testing unless presented herein Visual-m=nual ard;or Iaborzto-:;classificatie�. � methods of ASTh1 D-2487 and D-2488 were used as an identification guide for[he Unified Soil Classificatian System 0 > 5 m a Associated Earth Sciences, Inc. ` EXPLORATION LOG KEY o � � 5:.�z`Y�. � � r.._ y..-..,:' N '�1FY— !C'a. J 'J .'] Associated Earth Sciences,Inc. : EX loration Lo � � ❑ � � ' Project Number Exploration Number Sheet `� Y KE090396A EB-1 1 of 2 �roject Name Renton Memorial Stadium Ground Surface Elevation(ft) -ccation Renton WA Datum (�/q , Driller/Equipment GeologlC Drill/XL Date StarVFinish 11/4/(],A,1 914/Q� � Hammer WeighUDrop 140#1 30° Hole Diameter(in) 6° i �i� � � � � = o : .�I� (p � �' � Q �� ; �Q-� 3 BIQWS/F04f �- o T `�° �`�' ' �o � m � DESCRIPTION " � tio zo 3o ao ° - 2"asphalt. - 4"gravel base. -- _ _ - ___ __ _ _ _ Alluvium i � , S � Sand and gravel over moist fo wet,gray,silty fine SANDlfine sandy SILT. 7 - 5 � 2i s � = f I ; � Gravel pushed sampler down-sampled at 10'. i 10 S 2 � Wet, brownish gray,interbedded SILT and fine SAND,with trace organics. ti • j � ; I1 2 � � ! � Driller added mud at 11 112'- � � � i � S-3 � Wet, bluish gray,silty fine SAND,with trace woody debris 3 � � s s 15 3 ; � I I ; S-4 w'et, biuish gray, SILT,with fne sand i o . 20 ; 1 z t ' , I i � : I S-5 Wet,bluish gray,interbedded SILT and fine SAND 3 � � ; 25 I a � � i � ' S-6 Wet, bluish gray,silty fine to medium SAND,with siitier zones. 2 - 3 6 30 3 ; I i � S � Same, wet with gravel and scatfered organics 6 ' 35 �� 19 ` 8 � S 8 Wet, bluish gray,silty fine to medium SAND. 5 , � , 8 � i I " 40 6 I 0 o i N � G L E m � z S 9 Same,wet with organic beds i 3 ' v `+5 ' 10 zt ' m Sampfer Type (ST). s m 2"OD Split Spoon Sampler(SPT) � No Recovery M-Moisture Logged by: JPL c. m 3"�D Split Spoon 5ampler(D&M) � Ring Sample �L Water Level O Approved by: s � Grab Sample Q Shelby Tube Sample 1 Water Level at time of drilling (ATD) a Associated Earth Sciences,Inc. EX loration Lo � a � � t�� Project Number Explora'ion Number Sheet KE090396A EB-1 2 of 2 Project Name Renton Memorial Stadium Ground Surface Elevation(ft) �ocation Renton WA Datum N/A Driller/Equipment Geoloc�ic Drili/XL Date StarUFinish 11/4/(L4,1114/f1�3 Hammer WeighUDrop 140#1 30�� Hole Diameter(in) �� c a� '� � � U O > ' N Q Q� �,� J � BlowslFoot ,� Q- I S E tO � �a' � o a� � �T � �� DESCRIPTION � � m� �0 20 3o ao ° � f � Wet,bluish gray,fine to medium SAND,with gravel,siltier zones and s 5-10 , Woody debris(root?). 7 �22 ' � 50 i Driller reports gravel at 49 1/2'. �5 : ; I S >> Wet,bluish gray,GRAVEL,with sand and silt 36 j 3s ,�s � 55 43 i , ; S �Z Wet,bluish gray,siity fine SAND interbedded with brown organic silt 5 �j ' 60 3 � ! � �, S-13 Moist,bluish gray,silty fine to medium SAND. s II � 6 1 65 9� �', I S-14 I VVet.bluish gray,fine to coarse SAND,with gravel �3 - 18 3 70 _-- - - --- - ---- - --- - 16 I Bottom of exploration boring al 70 feet � 75 ' i i � 80 � i I i � I � �5 � 0 � n U I E U G Z a 90 � a Sampler Type{ST). m � m 2"OD Split Spoon Sampler(SPT) � No Recovery M-Moisture Logged by: JPL 0 o m 3"OD Split Spoon Sampler(D& M} � Ring Sample 2 Water Level Q Approved by: w � Grab Sample � Shelby Tube Sample 1 �`ater�evel at time of drilling(AT�) a Associated Earth Sciences,Inc EX loration Lo a � � � '`��, Project Number Exploration Number Sheet KE09Q396A EB-2 1 of 2 Praject Name Renton Memorial Stadium Ground Surface Elevation(ft) �ocation Renton WA Datum N/A Driller/Equipment Geologic Drill/XL Date StartlFinish 11/4iClg.,1 1l4/�9 Hammer WeighUDrop 140#I 30'� Hole Diameter(in) �� ! � a� � � ,� �/l U- O � - y) I °' L� -'� � � Blows/Foot � � Q �-E n S E f° >, �o" � o a� ' o T �n �"' v � m a DESCRIPTION 10 2o so aa 2"asphalt. - 4"gravel bas�. ' -- -- _ _-- –--— _–-- -- i Aliuvium S � Moist,rust-stained brownish gray,SILT,with sand and gravel 2 � t 2 7 � i 1 I S 2 Wet,rust-stained bluish gray,fine to medium SAND,with siit. 3 � 3 6 i0 3 Driller added mud at 13 t/2' , � S 3 I We1, bluish gray,silty fine SAND,interbedded with silt li 3; � � � 3i 5 15 � 2 I t S-4 �et, bluish gray,SILT,with very fine sand. z � � 1 2 j 20 1 � i � S-5 Wet, brown, PEAT,interbedded with SILT,with woody debris i � j z5 Biuish gray sand in sampler tip 2 4 � � � ( i � S-6 Wet,hluish gray,SILT,with fine sand and woody debris. 1 � ' 2 a i 3o z { i � Wet, bluish gray,fine to medium SAND,with siitier zones interbedded with 3 35 S� brown, PEAT !6 � � � � i + S-8 Wet, bluish gray.SILT,with organics interbedded with fine to medium 4 � � 0 40 �I sand- 2 5 ry 3 I � ' I � � I I i � ; Z S-9 Wet, bluish gray,SILT,interbedded with fine to medium sand 2 � � 3 � 45 4 � Sampler Type(ST): o m 2"OD Split 5poon Sampler(SPT) a No Recovery M-Moisture Logged by: JPL o m 3"OD Split Spoon Sampler(D&M) � Ring Sampie �? Water Level () Appraved by: Q 0 Grab Sample � Shelby Tube Sampie= Water Level at time of drilling (ATD) Associated Farth Sciences,Inc. EX loration Lo a � � � G; -,. Project Number � Exploration Number Sheet � " t��f KE090396A � EB-2 2 of 2 Project Name Renton IVlemorial Stadium Ground Surface Elevation(ft) Location Renton UVA Datum N/A _ OrillerlEquipment Geologic Drill/XL Date Start/Finish 11l4��A 11/4l�A Hammer WeighUDrop 140#I 30�� Hole Diameter(in) F" � a� N 1 U- O > ° / m r � O N �O B�OW$/FOOt � y �9 -v J U1 d �d� �a 3 a S E �`D >, �� O ( m � T � ic�cn a ca m ��r DESCRIPTION � � �0 20 30 40 'o i I i Wet, bluish gray,fine to medium SAND,with siltier zones s � S-10 � Driller reports gravel at 49' � 9 i � � 5� Gravel in sampler tip 1e 1 i S-11 Wet, bluish gray, fine to coarse SAND,with gravel. 5 15 �0 55 25 � Same,wet I 16 � S-12 � i �7 � 8 ; 60 ; 11 ' i � S-13 � Wet, bluish gray,silty fine to medium SAND,with siltier zones 9 � 65 i t 1 �ZZ I � i I S-;4 Wet, biuish gray,fine to medium SAND,with gravel a � � � ' 5 1 70 i 9 ' � Bottom of explora[ion boring at 70 Feet � �� ` ; I � i 75 � j � i l:L I I 85 � � ; 0 0 � �; , i v a E a I > �. Z I a C� t� � Sampler Type(ST). � m 2"OD Split Spoon Sampler(SPT) � No Recovery M-Moisture Logged by: JPL o � 3"OD Split Spoon Sampler{D& ��4j � Ring Sample SZ Water Levei O Approved by: i, � Grab Sample � Shelby Tube Scl?lDi?1 '�'�ater Lea�el at tir-�e or drill.ng(ATD) a Associated EarHi Sciences,Inc EX loration Lo . ❑ � � � � � Project Number Exploration Number Sheet `�'_ �•� " KE090396A EB-3 1 of 2 " Pro�ect Name Renton Memorial Stadium Ground Surface Elevation(ft) Location Renton WA Datum N/q ; Driller/Equipment Geologic DrilllXL Date StartlFinish 11/5/f19,11l5/f19 Hammer WeighUDrop 140#! 30�� Hole Diameter(in) �� C N I �N .. � ul U p .O > � �� fn °' L� —� � N Blows/Foot ;� n S � `° E, ��- a`� o ; a`� � m �cn o m pp :� � � T `� DESCRIPTION " � �0 2a so ao i° � Grass sod. � , -- _ -- � � FililModified Ground ' i i I S � Moist,rust-stained brownish gray,SlLT,with sand and organics � - _ _ _ - - 5 A1luvium 2 ; � s i i � Wet, rust-stained bluish gray,fine to medium SAND interbedded with silt 1 i lO S"2 and irace organics ! z �3 � � I• I i � Driller added mud at 13' � S_3 Wet,bluish gray.silty fine SAND,with trace organics � a � i 15 ' , a j i i f ' i i � S 4 Wet,bluish gray. silty fine to medium SAND � 15 30 � 20 I 15 i I � i I� I j � � S-S Wet, bluish gray.fine to medium SAND, interbedded wifh silt ; I 4 ej I 25 � 13 � i ' 5 I I I I I ' , I i j I S 6 Wet, bluish gray,SILT,with sand beds and peat beds �2 �� 2 7 30 i 5 j i , ! ', � i � � � '; S 7 : Wet, bluish gray,fine to medium SAND,interbedded with silt and peat ; 3 � i � �� ' 3 , 35 � � 2 � � � S S Wet, brown, PEAT,with beds of bluish gray silt 3 - - _ 3 � 40 4 0 . - N � I ;� ' � � I - � Drilier reports gravel at 43' , � I � z S 9 Wet, bluish gray,fine to coarse SAND,with gravel. � I3o i 48 8a � � 45 40 a Sampler Type(ST): � o m 2"OD Split Spoon Sampler(SPT) a No Recovery M-Moisture Logged by: JPL o m 3"OD Split Spoon Sampier(D& M) � Ring Sample � Water Level(� Approved by: w � Grab Sample � Shelby Tube Sample t Water Level at time of drilling (ATD) a Associated Eartli Sciences,Inc. EX loration Lo � � � � ,,,:, Project Number Exploration Number Sheet �'"` � KE090396A EB-3 2 of 2 Project Name Renton Memorial Stadium Ground Surface Elevation(ft) �ocation Renton VIfA Datum N/A DrillerlEquipment Geoloaic Drill/XL Date Sfart/Finish 1 1/5/flA 1 1/51(l� Hammer WeighUDrop 140#%3Q�� Hole Diameter(in) �," i c m _ � � N ,.,U� O � �� vl °' ''s > BIOWS/FOOt � � —N J in d .S E '� >. >� � O �i Cil p T � C7 a� o � C4 — DESCRIPTION " � � to 20 3o ao ;o i j � I � ' S-10� �et, bluish gray,GRAVEL,with fine to coarse sand. �3 50 � 25 � � i � S 1� Same,wet t0 � � 12 24 55 12 S �2 Wet,bluish gray,fine to medium SAND,interbedded with silt a s 6 12 60 6 i � S-13 I 1Net,bluish gray, SILT,with fine sand i 2 � 65 Bottom 4"wet, brown,organic SILT,with vdocdy debris j 5 White,ver,�fine SAND at sampler tip(tephra). ; � ' i , i S-14 �Net,bluish gray, SILT,interbedded with brown, PEAT,with woody debris. � - 70 _ __ _ I �4 i 23 i I Boltom of exploration boring at 70 feet ; � I i I � 75 I i i i ( j ( ( � � ; j � �o 85 ' � o j i o � ; N � i � ' I U � E � � i � 'o z a 90 � m Sampler Type(ST). m � 2"OD Split Spoon Sampler(SPT) � No Recovery h9-Moisture Logged by: JPL o � 3"OD Split Spoon Sampler(D& M} � Ring Sample � Water Level() Approved by: m � Grab Sample � Shelby Tube Sampie 1 �r��ater Level at time cf drilling(ATD) C Associated Eartl� Sciences,Inc EX loration Lo � � � � :�f, Project Number Exploration Number Sheet KE090396A EB-4 1 of 2 Project Name Renton Memorial Stadium Ground Surface Elevation(ft) Location Renton. WA Daturn N/A Driller/Equipment Geologic DriII/XL Date StaruFinish �5L(19.,11(5109 Hammer WeighUDrop 140#/ 30" Hole Diameter(in) �," � � � � N U p O � � N °' �Q —� � N BlowslFoot � L n m� °'n 3 � T � '' � � � � � c��n � � m o DESCRIPTfON to 20 3o ao FilllModified Ground - _ . _ - -Alluvium — - S_� Moist to wet,rust-stained bluish gray, SILT,with organics and sand beds. 3 �5 5 2 � i S 2 '; Wet, bluish gray,fine SANd, interbedded with siit i E - 2. 4 10 ', 2 i , ( � � ' Driller added mud at 13 V2' S-3 ! �et, bluish gray,fine to medium SAND,with trace organics. $ A }2 2 15 13 I �— , I � i Wet, bluish gray, SILT,with beds of fine to medium sand,with trace 3 � 20 � 4 organics � �� i � � i i � �� ; S-5 Wet,bluish gray,SILT,with fine sand and peat beds 2 -4 � I � 25 z ' �� - f j � � Wet, bluish gray,f:ne SAND,interbedded with silt,with trace organics and 2 � 3a S 6 woody debris. 3 �� I i , I � ' Wet, brown, PEAT,with woody debris interbedded wiih bluish gray,fine to 3 � 35 � S 7 coarse sand 2 � i 5 � ; I Wet, bluish gray,fine to medium SAND,interbedded with silt,with PEAT, 6 0 40 �' S"$ woody debris and trace gravel. 5 �24 0 N M � II , � � � ' - > I z° S 9 Wet, bluish gray,GRAVEL,with fine to coarse sand s I - 10 19 � 45 g � Sampler Type(ST): __ o Q 2"OD Split Spoon Sampler(SPT) � No Recovery M -Moisture Logged by: JPL o m 3"OD Split Spoon Sampler(D&��9) � Ring Sample SZ Water�evel O Approved by: w � Grab S�mp;e � Shelby Tube Sample 1 Water Level at time of drilling (ATD) a Associated Earth Sciences,Inc. E,X loration Lo � � � � � Project Number Explcration Number Sheet `�`�� ''�f KE090396A EB-4 2 of 2 Project Name Renton Memoria► Stadium Ground Surface Elevation{ft) _ocation Renton WA Datum N/A Driller/Equipment Geologic DriII/XL Date StarUFinish 11/5/(19,11151f1�1 Hammer WeighUDrop 140#/3d�� Hole Diameter(in) F" c a� � � (n U— O > � v� �' =Q —� � N BlowslFoot � n S E `��° >. �� o a� o .� � �� o � m L DESCRIPTInN " � 10 20 3c 40 � i l ; � I S-10 Wet, bluish gray,siity fine SAND,interbedded with silt with fine sand. 3 Z �5 50 3 I I S-11 Wet, bluish gray,SILT,with(ine to medium SAND beds and trace 3 i � i 5� organics � i � S-12 Wet, b(uish gray,fine to medium SAND,interbedded with silt,with trace 3 I � organics. 6 �� j 60 � White,very fine SAND at 59 112'(tephra) 9 �I i i � I I I ; � !S-13 Wet, bluish gray,silty fine to medium SAND,interbedded with silt. 6 ' � 65 �-� Gravel in sampler tip g I , � i � S-14 UVet, bluish gray,bedded GRAVEL,with sand i 5 3a I ♦ 70 ��9 i I � � � � S-15. Wet, biuish gray,GRAVEL r �2 � � 17 34 75 , � _ - — - -- _- - _ -- ,� ; ' I Bottom of exp!oralion boring at 75 feet i i i tgQ � i i � � � i � � i I � � 85 j o � 0 n r� I d ' � I . o � IZ � I � 90 � � Sampler Type(ST): � m 2"OD Split Spoon Sampler(SPT) � No Recovery M-Moisture Logged by: JPL � � 3"OD Split Spoon Sampler(D& ��-1) � Ring Sample i Water Leve!O Approved hy: � � Gra�Sampie � Snelby Tube Sample 1 ��ater Level at tim�of dri!ling (ATD) < VII. OTHER PERMITS I11is project�vill require a building permit from King Count��,Utility Develop Extensions for water from the Utility Department, and an NPDES permit from the Department of Ecology. The NPDES will include a S�A�'PPP and a spill prevention and cleanup report (included in the SWPPP). See Section S for a copy of the StiVPPP. COUGHLINPORTERLUNDEEN R��nhm h�1emurial5ta�iium 11 Kin*Counh bVashin};tc�n VIII. CSWPPP ANALYSIS AND DESIGN '� 1-his sc�tion lists d�e rt��uireitlents that ti.�ill be use�1 ��hcn designin�;the'I�E.SC plan f��r this site. A cc�pv��f �'�, the Draft SWPPP has been included in this secti�n c,n the fallo.��ing pages. The 51�1`PPP�vill be finaliz�d ��, after a contractor is brought on board Standard Requirements Erosion/Sedimentation Plan shall include the following: 1. Facilities required irich�de:Catclr basin filtersocks. (1.2.5-1). The project�+ill prc��i�1e se��imtnt protection at the existing catch basins and maintain existing hardscaped areas until areas��ill l� rE�- paved 2. Timing-For tlre period betzvee�i Not�ember 1 tltrouglt Rlarch 1 disturberl arec�s greater tltan 5,000 square feet left riridistr�rbed for r�iore tltatt 12 ho��rs»tt�st be cot�ered z��itli ntulclt,so�lding, or ylastic coz�eri�ig. A eo�istructiori phasing plau shall be�rorided to e�isrrre that erosion control rneasures are installed yrior to clearing and gra�li�tg. (1.2..5-1). Notes addressing each of thesE items have been placed on the civil engineering plans. 3. Planni�tg-Plart shall li»rit tribr�turi�Arainage to an aren to be clearert au�l grader�. Deliuente rlimensioit,stake arid flag cleari�:g liu�its (1.2.5-1). The clearing limits have been indicated on the'I�:SC plan. I�,'otes addressing this item have been plaied on the civil engineering plans. 4. Rez�egetatio�t-Reregetate areas to be cleared as saon as prneticable nftergrading. (].2.5-11. ?�ott:s addressing this item h�ve been placed on the civil engineering plans. COUGHLINPORTERLUNDEEN Rcnhm\1��m��na15W.1ium �� I�in};C�,unh'1V'ashin�;t�,n n Stormwater Pollution Prevention Plan For Re�lton '�lemorial Stadium Prepared For �Iorth��est Regional Office �190 - 160th Avenue SE Belle��ue, WA 98008-5452 ��>-6�9-7000 OH ner Developer Operator/Contractor R�nton School District Renton School District N:'A �00 SW 7th St 300 SW 7th St N'A R�ntc»l. ��'.=� 98��7 Renton. ��'A 980�7 N`.�� Project Site Location �O� Logan A��e I�', Renton W'a Certified Erosion and Sediment Control Lead N/A N/A SWPPP Prepared B�� Sean Robertson 4l3 Pine St, Suite 300 Seattle. Wa. 98101 206-3�3-0460 Coughlin Porter Lundeen. Civil Project Engineer S«'PPP Preparation Date 6,`21!10 Appro�imate Project Construction Dates December ?O10 Julv 2011 i ' n Contents 1.0 Introduction...............................................................................................................................l 2.0 Site Description �' ........................................................................................................................� 2.1 Existing Conditions �' ...........................................................................................................� 2.2 Proposed Construction Activities �' ......................................................................................� 3.0 Construction Storm��ater BMPs...............................................................................................5 3.1 The 12 BMP Elements.......................................................................................................5 3.1.1 Element #1 —Mark Clearing Limits................................................................5 3.1.2 Element #2 —Establish Construction Access...................................................5 3.1.3 Element #� —Control Flo��Rates....................................................................h 3.1.4 Element #4—Install Sediment Controls ..........................................................t 3.1.5 Element #5 —Stabilize Soils............................................................................� 3.1.6 Element #6—Protect Slopes ` ............................................................................ 3.1.7 Element #7—Protect Drain Inlets....................................................................�� 3.1.8 Element #8 —Stabilize Channels and Outlets................................................1(� 3.1.9 Element #9—Control Pollutants....................................................................l 1 3.1.10 Element #10 —Control De��-atering ...............................................................1 ] 3.1.11 Element #11 —Maintain BMPs......................................................................1, 3.1.12 Element #12 —Manage the Project................................................................1� 3.1.12 Element �12 —Manage the Project................................................................1� 3.2 Site Specific Bl�-1Ps..........................................................................................................1� 3.3 Additional Advanced BMPs............................................................................................1- �.0 Pollution Prevention Team ......................................................................................................1�� 5.1 Roles and Responsibilities...............................................................................................19 5.2 Team Members................................................................................................................20 6.0 Site Inspections and Nionitoring ? ............................................................................................�l 6.1 Site Inspection.................................................................................................................21 6.1.1 Site Inspection Frequency..............................................................................21 6.1.2 Site Inspection Documentation......................................................................��' 6.2 Stormwater Quality Monitoring �� ......................................................................................�_ 6.2.1 Turbidit� �� ........................................................................................................�_ 6.2.2 pH...................................................................................................................?; 7.0 Reporting and Recordkeeping � ................................................................................................ _ 7.1 Recordkeeping.................................................................................................................?; 7.1.1 Site Log Book ................................................................................................2� The site loE book is attached to this S��'PPP ................................................................?� 7.1? Records Retention..........................................................................................?; �; n 7.1.3 Access to Plans and Records..........................................................................25 7.1.4 Updating the SWPPP.....................................................................................26 7.? Reporting.........................................................................................................................26 7.2.1 Discharge Monitoring Reports.......................................................................26 7.2.2 Notification of Noncompliance......................................................................26 AppendixA — Site Plans.........................................................................................................31 Appendix B — Construction BMPs �' .........................................................................................J Z Appendix C —Alternative BMPs............................................................................................33 AppendiaD — General Permit ................................................................................................3� Appendix E — Site Inspection Forms (and Site Log) `' .............................................................�6 Appendix F— Engineering Calculations.................................................................................4� Appendix A Site plans ■ Vicinity map (��ith all discharge points) ■ Site plan ��ith TESC measures Appendi� B Construction BMPs ■ Possibl�- reference� in BMPs, but likely it will be a consolidated list so that the applicant can photocopy from the list from the SWMM. Appendix C Alternati�-e Construction BMP list ■ List of BMPs not selected, but can be referenced if needed in each of the 1? elements Appendix D General Permit Appendix E Site Log and Inspection Forms � Appendix F Engineering Calculations (if necessary) ■ Flows, ponds, etc... , � �� iii Storm�vater Pollution Prevention Plan 1.0 Inti•oduction This Storm�tiater Pollution Prevention Plan (S�'PPP) has been prepared as part of the NPDES stormwater permit requirements for the Renton Memorial Stadium construction project in Renton, Washington. The site is located on the north side of Renton, due north of the interchange for Interstate 405 (I-40�j and State Route 167 (Hv��y� 167). The existing site is �� 14.44-acre lot with a track and field and associated stadium. There are parking lots on the ne�rth and south sides of the site. The proposed development consists of the renovation of the existin�� stadium along vvith remo�-ing the north bathroom and ticket booth and replacing them ��ith ne�� structures. The eYisting court}ard south of the stadium will be replaced ��ith n�� c��nrrct� paving and landscaping will be installed around the east side of the tracl:. Construction activities ��ill include demolition, excavation, grading,relocation of on�it� serviceslutilities, new concrete and asphalt paving. The purpose of this SWPPP is to describe th� proposed construction acti�ities and all temporary and permanent erosion and sediment control (TESC) measures, pollution prevention measures, inspection/monitoring activities. and recordkeeping that �vill be implemented during the proposed construction project. Th� objectives of the S�'PPP are to: 4. Implement Best Management Practices (BMPs) to prevent erosion an�l sedimentation, and to identifi�, reduce, eliminate or prevent stormwater contamination and��ater pollution from construction activity. 5. Prevent violations of surface ��ater qualit�-, ground ��ater qualit�. ��r sediment manaaement standards. 6. Prevent, during the construction phase, adverse water quality impacts including impacts on beneficial uses of the receiving ��ater bv controllin�� peak flo��rat�s and volumes of stonn��atel� i�tinuft at the Permittze�� outfalls and do��-nstream of the outfall�. This S�'PPP was prepared using the Ecology- SWPPP Template do��nloaded from the Ecolog� website on June 21, 2010. This SWPPP was prepared based on the requirements set forth in the Construction Stormwater General Permit. Storm��rater Management Manual for Western Washington (SWMMWW 2005) and in the Storm��ater Management 1�ianual for Eastern V4'ashington (SVi-'MMEV�' ?004). The report is di�ided into seven main sections ��rith several appendices that include storm��-ater related reference materials. The topics presented in the eacl� of the main sections are: ■ Section 1 —Ii�TRODUCTION. Ihis section pro��ides a summar� description of the project, and the or��anization of the Sl�'PPP document. ■ Section 2— SITE DESCRIPTION. This section pro��idzs a detailed description of the existing site conditions, proposed construction activities, 1 Stormwater Po!lution Prevention Plan and calculated stormwater flo�� rates for existing conditions and post— construction conditions. � ■ Section 3 —CONSTRUCTION BMPs. This section provides a detailed description of the BMPs to be implemented based on the 12 required elements of the SWPPP (SWMME�'2004). ■ Section 4—CONSTRUCTION PHASING AND BMP IMPLEMENTATION. This section provides a description of the timing of the BMP implementation in relation to the project schedule. ■ Section 5 —POLLUTION PREVENTION TEAM. This section identifies the appropriate contact names (emergency and non-emergency). monitoring personnel, and the onsite temporar�- erosion and sedimentation control inspector ■ Section 6—INSPECTION AND MONITORING. This section provides a description of the inspection and monitoring requirements such as the parameters of concern to be monitored, sample locations, sample frequencies, and sampling methods for all stormwater discharge locations from the site. ■ Section 7 — RECORDKEEPING. This section describes the requirements for documentation of the BMP implementation, site inspections, monitoring results, and changes to the implementation of certain BMPs due to site factors experienced during construction. Supporting documentation and standard forms are provided in the follo��-ing Appendices: Appendix A— Site plans Appendix B —Construction BMPs Appendix C —Alternative Construction BMP list Appendix D —General Permit Appendix E — Site Log and Inspection Forms Appendix F —Engineering Calculations � Stormwater Pollufion Prevention P(an 2.0 Site Description 2.1 Existing Conditions The proposed site is located just north of I40� and highway 167 in Renton, Was]Zington. A site vicinit}- map and coordinates are provided in Appendix A. The existing site is a 14.44-acre lot ��-ith a track and field and associated stadium. The proposed development consists of the renovation of the existing stadium along «-ith removing the north bathroom and ticket booth and replacing them «-ith ne«- structures. The existing courtyard south of the stadium w-i11 be replaced with ne��T concrete paving and landscaping will be installed around the east side of the track. The topography of the site and surrounding properties gentlti- slopes to the ��-est. Soils are classified as Till, Quarternary Alluvium. The site is well drained and ground«�ater lies approximatel}' 6 feet below the surface. Runoff from the site generall�� drains from east to��est to a series of catch basins. The catch basins con�-cy runoff to a storm drain system that flo��s to either the north��est or southwest corners of the site where they discharge to the Cedar River. At the point of discharge. Cedar River is listed as a Category 5 polluted water of the state under the State's Clean Water Act Section 303(d) list. due to fecal coliform bacteria contamination. dissol��ed o�ygen le��els. a�Id temperature. There are no critical areas on the site such as hi��h erosion risk areas, ��etlands. streams. or steep � slopes (potential landslide arza). The site does sit ��ithin a portion of the 100-��r flood plain for the Cedar River. 2.2 Proposed Construction Activities The proposed development consists of the reno�-ation of the existing stadium along��ith � remo�-ing the north bathroom and ticket booth and replacing them «�ith new structures. The eaisting courtyard south of the stadium ��ill be replaced��ith ne�� concrete pa�°ing and landscaping ��-i11 be installed around the east side of the track. . No ��ater quality or detention facilities are planned as part of this development. New sanitary, electrical, water and storm drain � � utilities will also be constructed. Construction activities «ill include site preparation, TESC installation, demolition of the existing north bathroom and ticket booth. exca�-ation for retrofitting the stadium building foundations, asphalt'concrete paving. construction of a ne�� tick�t booth/bathrooms. and renovation of the , � � Stormwater Pollution Prevention Plan e�isting stadium. The schedule and phasing of BMPs during construction is provided in Section 4.0. The site disturbance to the site will be localized areas that require repa��ing and the construction of the ne« north bathroom/ticket booth. No TESC calculations are attached because of the minor disturbances. � After the replaced north building is constructed and all ne��° utilities are installed. the site ��ill be , graded and pa�•ed. A landscape huffer area ��il1 be constructed on the east side of the site. The following summarizes details regarding site areas: The follo��ing summarizes details regarding site areas: ■ Total site area: 14.44 acres ■ Percent i�l�pervious area before construction: 78.1 % ■ Percent impervious area after construction: 77.9 % ■ Disturbed area during construction: 2.5 acres ■ Disturbed area that is characterized as impervious (i.e., access roads, staging, parking): 1 acres ■ ?-year stormwater runoff peak flow prior to construction (existing): NIA cfs ■ 10-year storm��ater runoff peak flo��- prior to construction (existing): :�;'A cfs ■ 2-year storm��ater runoff peak f7o�� during construction: N/A cfs ■ 10-}ear storm«-ater runoff peak flo��- during construction: N/A cfs ■ 2-year storm��,ater runoff peak flo�� after construction: N/A cfs ■ 10-year stormwater runoff peak flo�� after construction: N/A cfs No storm��ater flo�� calculations are provided in Appendix F at this time. 4 Stormwater Pollution Prevention Plan 3.0 Construction Stormwater BMPs 3.1 The 12 BMP Elements 3.1.1 Element #1 —Mark Clearing Limits To protect adjacent properties and to reduce the area of soil exposed to construction, the limits of construction «-ill be clearly marked before land-disturbing activities begin. Trees that are to be preserved, as ��-e11 as all sensitive areas and their buffers, shall be clearly delineated, both in the field and on the plans. In general, natural vegetation and native topsoil shall be retained in an undisturbed state to the maximum extent possible. The B'�-1Ps rele�ant to markin� the clearin`� limits that will be applied far this project include: • High Visibilit�� Plastic or '��letal Fence (B'�1P C 103) Alternate BZ�TPs for marking clearin�� limits are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Perniit (Appendi� D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendi� D), the Certified Erosion and Sediment Control Lead ��-i11 promptiv initiate the implementation of one or more of the alternati��e B��1Ps listed in appendi� C atter the tirst si�rn that e�isting BI��1Ps are ineffecti��e or failin�. 3.1.2 Element #2 — Establish Construction Access Construction access or acti�-ities occurring on unpa�ed areas shall be minimized. �et ��her� necessary. access points shall be stabilized to minimize the tracking of sediment onto public roads. and��heel wrashing, street sweeping, and street cleaning shall be employed to prevent sediment from entering state �vaters. All ��ash ��aste«ater shall be controlled on site. The specitic B?�1Ps relat�d to establishing construction access that ��ill be used on this project include: • No BI�1P, tc� re implement�d Stormwater Po!lution Prevention Plan Alternate construction access BMPs are included in Appendi� C as a quick reference tool for the onsite inspector in the e�,�ent the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisf} the requirements set forth in the General NPDES Permit (Appendi� D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead ��ill promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failin�. 3.1.3 Element#3 —Control Flo�r Rates In order to protect the properties and watervva}s do��nstream of the project site, stormwater discharges from the site will be controlled. The specific BMPs for flo��- control that shall be used on this project include: • No B1�-1Ps to be implemented Alternate flo�� control BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a ��iolation(s) of the NPDES Construction Storm«�ater permit (as provided in Appendi� D), the Certified Erosion and Sediment Control Lead��ill promptly initiate the implementation of one ar more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. The project site is located ��-est of the Cascade Mountain Crest. As such, the project must comply with Minimum Requirement 7 (Ecolog�� ?005). In general, discharge rates of storm��ater from the site �vill be controlled ��here increases in impervious area or soil compaction during construction could lead to downstream erosion, or ��-here necessary to meet local agency storm��ater discharge requirements (e.g. discharge to combined se«-er systems). 3.1.4 Element#4—Install Sediment Controls All storm�i-ater runoff from disturbed areas shall pass through an appropriate sediment removal BMP before leaving the construction site or prior to being discharged to an infiltration facility. The specitic BMPs to be used for controlling sediment on this project include: 6 Stormwater Pollution Prevention Plan • Storm Drain Inlet Pl-otection (B1��1P C`'?Oj Alternate sediment control B11Ps are included in Appendia C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfi� the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sedimenl control issues that may cause a violation(s) of the NPDES Construction Starmwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative B'VIPs listed in Appendix C after the first sign that e�isting BMPs are ineffectil-e or failing. In addition, sediment �;-ill be remo�°ed from paved areas in and adjacent to construction ��ork areas manually or using mechanical s«-eepers, as needed. to minimize tracking of sediments on vehicle tires a��a�� fram the site and to minimize ��ashoff of sediments from adjacent streets in runoff. �'�11ene��er possible. sediment laden »ater sliall be discharged into onsite. relati�zh� le�el. vegetated areas (BMP C240 paragraph �, page 4-102j. In some cases. sediment discharge in concentrated runoffcan be controlled usi�l`� p�rmanc�lt stormwater BMPs (e.g., infiltration swales, ponds, trenches). Sediment loads can limit the effectiveness of some permanent storm��ater BN1Ps, such as those used for infiltration or biofiltration; ho��•ever, those BMPs designed to remove solids by settling (��et ponds or detention pondsj can be used during the construction phase. �'hen permanent storm��ater B�-1Ps ��-ill be used to control sediment discharge during construction. the structure will be protected from eYcessive sedimentation ��ith adequate erosion and sediment control BMPs. Any accumulated sediment shall be removed after construction is complete and the permanent storm«ater B'��IP will be restabilized with , �t:�t� . �; ��,�_�'.�_ . . � � . . �-.��- .� tl�. .� �.��.,� ,�;�;I��. site has been stabilized. The follo��ing BMPs will be implemented as end-of-pipe sediment controls as requir�.��.1 .� ��,_ permitted turbidity limits in the site discharge(s). Prior to the implementation of these technologies, sediment sources and erosion control and soil stabilization BMP efforts «ill l� maximized to reduce the need for end-of-pipe sedimentation controls. ■ Temparary Sediment Pond (BMP C241) ■ Construction Storm��ater Filtration (BMP C251) � �� 7 Stormwater Pollutron Prevention Plan ■ Construction Storm��-ater Chemical Treatment (BMP C 250) (implemented onl�� ith prior��ritten approval from Ecolog��). 3.1.5 Element #5—Stabilize Soils Exposed and unworked soils shall be stabilized ��ith the application of effective BMPs to prevent erosion throughout the life of the project. The specific BMPs for soil stabilization that shall be used on this project include: • Temporary and Permanent Seeding (BMP C 120) • Plastic Covering (BMP C123) • Dust Control (BMP C 140) Alternate soil stabilization BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisft- the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead ��ill promptly initiate the implementation of one or more of the alternati�e BMPs listed in Appendix C after the tirst sign that existing BMPs are ineffective or failing. The project site is located west of the Cascade Mountain Crest. As such. no soils shall remain exposed and unworked for more than 7 days during the dry season (May l to September 30) and 2 days during the wet season (October 1 to April 30). Regardless of the time of}�ear, all soils shall be stabilized at the end of the shift before a holiday or��eekend if needed based on weather forecasts. In general, cut and till slopes ��ill be stabilized as soon as possible and soil stockpiles ��ill be temporaril}� covered with plastic sheeting. All stockpiled soils shall be stabilized from erosion, protected with sediment trapping measures, and ��here possible, be located away from storm drain inlets, waten�ays, and drainage channels. 8 Stormwater Pollution Prevention Plan 3.1.6 Element #6— Protect Slopes .All cut and fill slopes v�i11 be designed. constructed, and protected in a n�anner than minimize� erosion. The follo��in� specific E3��iP5 ��ill be used to protect �lopes for this prc�ject: • Temporan� and Nermanent Seedin�r 1I3�9P Cl�'0) .alttrnate slope prutcrtion B��IPs are include� in :�ppendi� C as a quicl: rtfertnce tool t��r thc ' onsite inspector in the event the B'vIP(s) listed above are deemed ineffective or inappropriate during construction to satis�� the requirements set forth in the General NPDES Permit (Appendi� D). To avoid potential erosion and sediment control issues that ma} cause a violation(s) of the NPDES Construction Storm��ater pernlit (as pro�ided in Appendix D). the Certified Erosion and Sediment Control Lead ��ill pr�mptly initiate the implementation of one or more of the alternati�e BI�iPs listed in Appendix C after the tirst si`�n that e�isting B?�1Ps are ineffecti��e or failin�. 3.1.7 Element #7 — Protect Drain Inlets All storm drain inlets and culverts made operable during construction shall be prutected to pre��ent untiltered or untreated �ti ater from entering the drainage con��e}ance system. Ho��e��r. the first priority is to keep all access roads clean of sediment and keep street ��ash «ater separat� from entering storm drains until treatment can be provided. Storm Drain Inlet Protection (B�1P C2?0) ��ill be implemented for all drainage inlets and culverts that could potentiall� be impacted b�� sediment-laden runoff on aild n�at- the pr��jc rt ;it�. The toll��in�� inlet �rotecti��n m�asur�s ��ill hc applied c�n this }�roj�ct: Drop Inl�t Protection • E�cavated Drop Inl�t Pr��t�ction • Blocl: and Gra��el Drop Inlet Protection • Gra�el and ��'ire Drop Inlet Protection 9 Stormwater Pol/ution Prevention Plan • Catch Basin Filters • Alternative BN1P not i�Icluded in the SW��1'��W�' (?005) or SW'N1MEVi-' (2004) • Culvert Inlet Sediment Trap • Alternative BMP not included in the SWI��1I��1��'W (�005) or SVl'I��1M�;W (?004) If the BMP options listed abo��e are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D), or if no BMPs are listed above but deemed necessary during construction, the Certified Erosion and Sediment Control Lead shall implement one or more of the alternative BMP inlet protection options listed in Appendix C. 3.1.8 Element #8 — Stabilize Channels and Outlets ti�'here site runoff is to be con�-eyed in channels. or discharged to a stream or some other i�atural draina��e point. efforts will be taken to prevent do��nstream erosion. The specitic B�iPs fot• channel and outlet stabilization that shall be used on this pi-oject include: • \o B�1Ps to be implemznted A1ter�latz cl�annel and outlet stabilization B1��4Ps a1�e included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPD�S Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead ��ill promptly initiate the implementation of one or more of the alternati��e B1�iPs listed in Appendix C atter the tirst si�n that e�isting Bl�1Ps ai-e ineffective or failin�. The project site is located west of the Cascade �lountain Crest. �s such, all temporary on-site conveyance channels shall be designed, constructed, and stabilized to prevent erosion from the expected peak 10 minute velocin- of flo�� from a Type 1 A, 10-year. 24-hour recurrence interval 10 Stormwater Pollution Prevention Plan storm for the de��eloped condition. alternati��elti�, tlle l0-��eat�. 1-hour pzak t7o��rate indicated b�� an approved continuous runoff simulation model, increased by a factor of 1.6, shall be used. Stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent streambanks. slopes, and do��-nstream reaches shall be provided at the outlets of all conveyanre svstems. 3.1.9 Element #9 — Control Pollutants All pollutants, including �-aste materials and demolition debris, that occur onsite shall be handled and disposed of in a manner that does not cause contamination of stormwater. Good housekeeping and preventative measures will be taken to ensure that the site will be kept clean. ��ell organized. and free of debris. If required, B1��tPs to be implemented to control specitic sources of pollutants are discussed belo��. Demolition: • Dust released from demolished side��all:s, buildin�s. or struct�n�es ��ill be controlled using Dust Control measures (BN1P C 140). ■ Storm drain inlets vulnerable to stormwater discharge carryin� dust. soil. or debris ��-i11 be protected using Storm Drain Inlet Protection (BMP C2`'0 as described above for Element 71. ■ Process ��ater and slurry resulting i�rom sa��cuttin�� and surfacin�� operations ��ill be prevented from entering the waters of the Stat� b� implementing Sa��cuttin�� and Surfacing Pollution Pre��ention measures (BI�1P C1�2). Conc►-zte and ��rout: ■ Process ��ater and slum� resulting irom concrete ��ork ��ill be pre��ented from entering the ��aters of the State b� implementina Concrete Handli►1� measures (B'��iP C 1>1 I. The facilit�� does i�ot require a Spill Pre�ention. Control_ and Countermeasln•e (SPCC) Plan under the Federal re��ulations of the Clean �T�-ater _�ct (C«�A). 3.1.10 Element #10 —Control De�ratering There ��ill be no de�tiateriil� as part of this constrtiction pr��ject. II Stormwater Pollution Prevenfion Plan 3.1.11 Element #11 — Maintain BMPs All temporary and permanent erosion and sediment control BMPs shall be maintained and repaired as needed to assure continued performance of their intended function. Maintenance and repair shall be conducted in accordance ��ith each particular BN1Ps specifications (attached). Visual monitoring of the BMPs �i11 be conducted at least once every calendar week and within 24 hours of an�� stormwater or non-stormv�-ater discharge from the site. If the site becomes inactive, and is temporaril�� stabilized,the inspection frequenc� �4�i11 be reduced to once every month. All temporary erosion and sediment control BMPs shall be removed ��ithin 30 days after the final site stabilization is achieved or after the temporary BMPs are no longer needed. Trapped sediment shall be removed or stabilized on site. Disturbed soil resulting from removal of BMPs or vegetation shall be permanentiv stabilized. 3.1.12 Element #12 — Manage the Project Erosion and sediment control BMPs for this project ha�e been designed based on the following principles: ■ Design the project to fit the existing topography, soils, and drainage patterns. ■ Emphasize erosion control rather than sediment control. ■ '�-'[inimize the extent and duration of the area exposed. � ■ Keep runoff velocities low. ■ Retain sediment on site. ■ Thoroughly monitor site and maintain all ESC measures. ■ Schedule major earthwork during the dry season. In addition, project management ��ill incorporate the ke�� components listed belo��: (West Response) As this project site is located ��est of the Cascade Mountain Crest, the project «-ill be managed according to the follo��-in� key project components: Phasing of Construction ■ The construction project is being phased to the extent practicable in order to prevent soil erosion, and. to the maximum extent possible. the transport of sediment from the site during construction. 12 Stormwater Pollution Prevention Plan ■ Re�-egetation of exposed areas and maintenance of that vegetation shall be an integral part of the clearing activities during each phase of construction. per the Scheduling BMP (C 162). Seasonal Vl�'ork Limitations ■ From October 1 through April 30, clearing, grading, and other soil disturbing activities shall only� be permitted if shown to the satisfaction of the local permitting authority that silt-laden runoff��ill be prevented from leaving the site through a combination of the following: � ❑ Site conditions including existing vegetative coverage, slope, soil n pe, and pro�imitti- to receiving ��-aters; and ❑ Limitations on activities and the extent of disturbed areas; and ❑ Proposed erosion and sediment control measures. ■ Based on the information provided and!or ]ocal«�eather conditions. the local permitting authoritv may eapand or restrict the seasonal limitation on site disturbance. ■ T}Iz follo�i i�l�� acti��iti�. are e�em}�t ti�om the ;easonal cl�arin�r and «ra��i�l�,� limitations: � ❑ Routine maint�n�u�� 3n�i n�cc<�ar� r��air �,f rro�i�,n an�� •zdim�nt control BMPs: ❑ Routine maintznance of public t�,i��iliti�� ur ��i�ti�� utilit� structures that do not expose th� ��il ��r r��«lt in th; ,��1»��.il �,t th�• vegetative cover to soil; and ❑ Activities where there is 100 percent infiltration of surface ��.it�:� runoff��ithin the site in approved and installed erosion and sediment control faciliti��. Coordination with Utilities and Other Jurisdicti��n� ■ Care has been taken to coardinate ti��ith utilities. other constructi�n projects, and the local jurisdiction in preparing this SV�'PPP and schedulin� the construction ��ork. - ___ _ _ ___ _ . - i� Stormwater Pollution Prevention Plan Inspection and Monitoring ■ All BMPs shall be inspected, maintained, and repaired as needed to assure continued perfornlance of their intended function. Site inspections shall be conducted by a person who is knowledgeable in the principles and practices of erosion and sediment control. This person has the necessary skills to: ❑ Assess the site conditions and construction activities that could impact the quality of stormwater, and ❑ Assess the effectiveness of erosion and sediment control measures used to control the qualitv of stormwater discharges. ■ A Certified Erosion and Sediment Control Lead shall be on-site or on-call at all times. ■ Whenever inspection and/or monitoring reveals that the BMPs identified in this SV�'PPP are inadequate, due to the actual discharge of or potential to discharge a significant amount of any pollutant, appropriate BMPs or desi;�n chan�es shall be implemented as soon as possible. Maintaining an Updated Construction SVi-'PPP ■ This SWPPP shall be retained on-site or within reasonable access to the site. ■ The S�'PPP shall be modified whenever there is a change in the design, construction, operation. or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the state. ■ The SW'PPP shall be modified if, durii�� inspections or investigations conducted by the owner�operator, or the applicable local or state regulatory authority, it is deternlined that the SVVPPP is ineffective in eliminating or significantly minimizing pollutants in storm��ater discharges from the site. The SWPPP shall be modified as necessary to include additional or modified BMPs designed to correct problems identified. Revisions to the SWPPP shall be completed ��-ithin seven (7) da�rs follo��ing the inspection. --- 14 Stormwater PoNution Prevention Plan ■ Desi��n thr �,r��jtct tu iit th� e�iatin�� tu}�u��raE,h�. soils. an�i �lraina��e patterns. ■ Emphasize erosion control rather than sediment contr��l. ■ Minimize the extent and dtirati�n of the area e�p�seci ■ Keep runoff velociti�� '��, , ■ ,.��,�� ,�� . � �_��_ � ' , i� �_ � _- -� ��I __�I��_ �� .�!I ; 1( t�,_. _ , ■ Schedule maj or earthwork during the �,:��, ��._�� In addition, project management �vill incorporate the key compolients listcd bel�� As this project site is located west of the Cascade'�1��int�in C'rest. the �r�ject ��i'� according to the follo�tin�� l:e� ��r�iect c�m��ne� Phasin�_ . to prevent soil erosion, and, to the ma�imum e�tent possible, the transport of sediment from the site during construction. ■ Revegetation of exposed areas and maintenance of that vegetation shall be an inte�ral part of the clearing activitics during each phase of construction, per the Scheduling BMP (C 16�). � Seasonal Work Limitations ■ From October 1 through April 30, clearing. grading, and other soil disturbing activities shall only be permitted if sho��n to the satisfaction of the local permitting authority that silt-laden runoff��il' l�� i�r�•��r?�cl f�r��n� leaving the site through a combination of the followin��. ❑ Site conditions including e�isting vegetati�-e c��ca��. slupe. ��il type, and proximity to receiving ��-aters; and ❑ Limitations on activities and the e�tent of disturbed areas: and ❑ Proposed erosion and sediment control measures. 15 - - Stormwater Pollution Prevention Plan '_ ■ Based on the information provided and/or local weather conditions, the local permitting authorit� may expand or restrict the seasonal limitation on site disturbance. ■ The following activities are exempt from the seasonal clearing and grading limitations: o Routine maintenance and necessary• repair of erosion and sediment control BMPs; ❑ Routine maintenance of public facilities or existing utility structures that do not expose the soil or result in the removal of the vegetative cover to soil; and ❑ Activities w�here there is 100 percent infiltration of surface w�ater runoff within the site in approced and installed erosion and sediment control facilities. Coordination with Utilities and Other Jurisdictions ■ Care has been taken to coordinate with utilities, other construction projects. and the local jurisdiction in preparing this S�'PPP and scheduling the construction ��ork. Inspection and Nlonitoring ■ :�ll BMPs shall be inspected, maintained, and repaired as needed to assure continued performance of their intended function. Site inspections shall � be conducted by a person«-ho is kno��-ledgeable in the principles and practices of erosion and sediment control. This person has the necessary skills to: ❑ Assess the site conditions and construction activities that could impact the quality of storm��ater, and ❑ Assess the effectiveness of erosion and sediment control measures used to control the quality of stormwater discharges. ■ A Certified Erosion and Sediment Control Lead shall be on-site or on-call at all times. ■ VVhenever inspection and/or monitoring reveals that the BMPs identified in this SWPPP are inadequate, due to the actual discharge of or potential to discharge a significant amount of any pollutant, appropriate BMPs or design changes shall be implemented as soon as possible. 16 Storm�vater Pollution Prevention Plan �I� �1��intainin�� an l� ,�l�it��1 Con�tructi��n S�'��PI'P �� I ■ This S��'PPP shall hc retaincd �,n-;it< <,r ��ithin r�a;��nahl� ��rc:� t�� thc �� sit�. ■ 111e SVa�PPP shall b� moditiz�i ��hcne��er there is a chan�e in thz desi��n. construction, operation, or maintenance at the construction site that h.l<. �,r c�uld ha��e. a siRnificant effect �n the dischar�e c�t , , :, � , � i � _ _ , _ � -_ ., . _ __ - I conducted by the owner�'operator, or the applicable local or state I regulaton� authoriri�, it is determined that the SVVPPP is ineffecti�: �I eliminating or significantl� minimizing pollutants in stormwater � discharges from the site. The SWPPP shall be modified as necessan w include additional or modified B1�4Ps designed to correct problems identified. Revisions to the S�'l'PPP �l,all h� c��n,rlete�� ithin �c�en �?1 da��. f�,ll��in« the in��ect��. 3.2 �lt� ��eCIf1C �.ti'l�'' Site specific BMPs are sho«n on the TESC Plan Sheets and Details in Appendix A. These sit specific plan sheets ��ill be updated annuall��. 3.3 Additional Advanced BMPs The BMP implementation schedule listed belo�� is keyed to proposed phases of the construction project, and reflects differences in BMP installations and inspections that relate to wet season construction. The project site is located ��-est of the Cascade Mountain Crest. As such. the dry season is considered to be from Ma} 1 to September 30 and the ��et season is considered to be from October 1 to April 30. ■ Install ESC measures: December ?O10 ■ Install stabilized construction entrance: December ?O10 ■ Begin clearing and grubbing: December 2010December 2010 17 Stormwater Pollution Prevention Plan � � ' � � 18 Stormwater Pollution Prevention Plan 5.0 Pollution Prevention Team 5.1 Roles and Responsibilities The pollution prevention team consists of personnel responsible for implementation of the S«PPP, including the following: ■ Certified Erosion and Sediment Control Lead (C�SCL)—primar} contractor contact, responsible for site inspections (BMPs, visual monitorinQ. samplin�_ etc.): to be called upon in case of failure of ai1� k.ti(� m�a��ire�. ■ R��iacnt �n��inc�r— Fc�r proj�ct; ��ith en��int�i��d sti�ucttir�; ��nl� (sediment ponds,%traps, sand filters, etc.): site representative for th� o��n�r that is the project's supen-ising engineer responsible for inspections a�1�1 issuing instructions and dra«-in�s to the contractor's site supervisor or representative ■ Emergency Ecology Contact— individual to be contacted at Ecology in case of emergenc�. ■ Emergency Owner Contact— individual that is the site o��•ner ��: representative of the site o��ner to be contacted in the case of a� . 1-epresentati�e of the site o�vner than can be contacted if required. ■ Monitoring Personnel —personnel responsible for conducting ��at�� quality rnonitoring; for most �ite� thi� ��ei��n i� ;�I��, tl�e C'trtifi.ei� ! � and Sediment Control Lead Stormwater Pollution Prevention Plan 5.2 Team Members Names and contact information for those identified as members of the pollution prevention team are provided in the following table. Title Name(s) Phone Vumber Certitied Erosion and Sediment Control Lead(CESCL) 1�iA V`A Resident En�ineer Nr'A-To be Determined fY/A Fmergenc� Ecoloeti Contact N/A-To be Determined � F.mergency O��ner Contart N/A-To be Detennined --. '�on-F.mergenc� Ecology Contact N/A-To be Determined � �7onitoring Personnel N/A-To be Determined — - 20 Stormwater Pollution Prevention Plan 6.0 Site Inspections and Monitoring Monitoring includes visual inspection, monitoring for w-ater quality parameters of concern, and documentation of the inspection and monitoring findings in a site log book. .A site log book �cill be maintained for all on-site construction activities and ��ill include: ■ A record of the implementation of the S�'�'PPP and oth�r permit requirements: ■ Sit�• in�pe�ti��n�_ an�j_ • �ll�l'Ill\V��1�C C�U�l�ll�� 1]1l�]11TC)I'lll�'. For convenience, the inspection form and water qualitti monitorin� forms included in thi� SVl-'PPP include the required information for the site log book. This SWPPP may function as tl�; site log book if desired, or the forms may be separated and included in a separate site log h�c�l.. Ho��ever, if separated, the site log book but must be maintained on-site or v��ithin reasonahl� � accc�s t� the site and he ��ade a��ailahle up�n reque�t t� Fcoloa�� r the local jurisdicti��r� 6.1 Site lnspectior� A1� BMPS ��ill b�' 111SpeCtC'll_ �]i�U111u11i;�L au�l .'��ull��l a, 1��;C�l l.� �t»�u�� L��Ilil�iul�1 ��L1il�lll,��ul.� of their intended funetion. The inspector��ill be a Certified Erosion and Sediment Control Lead (CESCL) per BMP C160. The name and contact information for the CESCL is pro��ided in Section 5 of this SVI�'PPP. Site inspection will occur in all areas disturbed by construction activities and at all storm��ater discharge points. Stormwater �vill be examined for the presence of suspended sediment, turbidity, discoloration, and oily sheen. The site inspector��-i11 evaluate and document the effecti��eness of the installed BMPs and determine if it is necessary to repair or replace any of the BMPs to improve the qualiri� of storm��•ater discharges. All maintenance and repairs ��-ill be documented in the site log book or forms provided in this document. .all ne�� B�TPs �r de�i��l� changes «°ill be documented in the S��'PPP as soon as pos�ibl�� 6.1.1 tiitt� In��cctiiin F rcyucnc� Site inspections will be conducted at least once a ��ti�e�k and�ti�itl�in ?-� hours follo�ti�ing am� dischar�e from the site. For sites��-ith temporan- stabilization measures, the site inspection frequency can be reduced to once every month. �� Storm�,vater Pollufia� Preve��tion Plan 6.1.2 Site Inspection Documentation The site inspectar�uill record each site inspectiu�l u5ing tlle sit� lu�� inspection torms pro��id�d i�l Appendix E. The site inspection log forms may be separated from this SWPPP document, hut «�ill be maintained on-site or within reasonahle access to the sit� a�ld be �11ade available upc�n � reyuest to Ecolo�}� o►� the local j�u•isdiction. 6.2 Stormwater Quality Monitoring 6.2.1 Turbidih• Turbidity sampling and monitorin� ��i11 be conducted during the entire construction phase of the project. Samples will be collected dail} at the catch basin in the northwest corner of the site (CBS). If there is no flow in this catch basin. the attempt to sample will be recorded in the site � log book and reported to Ecology in the monthly Discharge Monitoring Report (DMR) as "No Discharge". Samples «�ill be analyzed for turbidity using the EPA 180.1 analytical method. The ke�� benchmark turbidity value is 2� nephelometric turbidity units (NTU) for the downstream recei�ing ��ater body. If the 2� NTU benchmark is exceeded in am� sample collected from CB�. the follo�ving steps v�-ill be conducted: 1. Ensure all BMPs specitied in this SWPPP are installed and functioning as intended. 2. Assess «�hether additional BMPs should be implemented. and document modified BMPs in the SV4'PPP as necessary. 3. Sample discharge dail} until the discharge is 2� NTU or lo��-er. If the turbidit�� exceeds 2�0 NTi1 at any time, the follo��ing steps ��ill be conducteei: 1. Notify Ecology by phone��ithin 24 hours of anal��sis (see Section S.0 of this SVdPPP for contact inforn�atio�l). 2. Continue sampling dail}- until the discharge is ?� �J�I�L or lo��cr Initiate additional treatment BMPs such as off-site treatment. infiltration, tiltration � and chemical treatment within 24 hours, and implement those additional treatment BMPs as soon as possible, but ��ithin a minimum of 7 days. 3. Describe inspection results and remedial actions taken in the site log book and in monthl�� discharge monitorin� reports as described in Secti�n 7.0 of this S��l%PPP. �� Stormwater Pollutron Prevention Plan 6.2.2 pH Sampling and monitoring for pH ��ill occur during the phase of construction when concrete pouring will be conducted until fully cured (3 weeks from last pour) and discharges are documented to be belo��-pH 8.�. Samples will be collected weekly at the sedimentation pond prior to discharge to surface ��-ater. Samples ��ill he analvzed f�r pH usin�T a calibrated pH ��eter and recorded in the site log book. The ke} benchmark pH value for stornn�-ater is a malimum of 8.�. Ifa pH �reater than 8.� is measured in the sedimentation trap/pond(s) that has the potential to dischar�e to surface ��ater. the follow�ing steps will be conducted: �. Prevent (detain) all dischar�es fr��m lea��in�� thc site and ent�rin�� surfac� �ti�aters or storm drains if the pH is greater than 8.ti 5. Imp1et11ent CO, sparging or dr� ice treatment in accordance ��ith Ecolog�� BI�1P C2�2. 6. Describe inspection results and remedial actions that are taken in the site lo� book and in monthl�- discharge monitoring reports as described in Section 7.0 of this S�'�PPP. ,; Stormwater Pollutron Preventron Plan 7.0 Reporting and Recordkeeping 7.1 Recordkeeping 7.1.1 Site Log Book A site log book will be maintained for all on-site construction activities and ��ill include: ■ A record of the implementation of the SWPPP and other permit reqt►irernents: ■ Sit� inspections: and. • St��rm��3ter qualit�� monitorin��. For convenience, the inspection form and water quality monitc>rin�� ti�rm� in�lu�i�d in thi� �Vl'PPP iilcltide thc r��uii�ed int��rmati��n fe�r th� �ite lo� r�,�,l:. �I hc sitc lu�� I�r��l, i� att.ich��1 tu thi� �� t'I'f' 7.1.2 Recor�ls Iletcntion Records of all monitoring i Storm��ater Pollution Pre�-ention Ylan. and any �ther documentation ot compliance ��ith per►>> requirements ��-ill be retained during the life of the construction project and for a minimum oi three years follo��ing the termination of permit coverage in accordance with permit condition SS.C. 7.1.3 Access to Plans and Records The SV1-'PPP. General Permit, Notice of Authorization letter, and Site Log Book ��ill be retained on site or��-ithin reasonable access to the site and ��-i11 be made immediately available upon request to Ecology or the local jurisdiction. A copy of this SV�'PPP ��ill be pro�-ided to Ecology within 14 days of receipt of a written request for the SV1'PPP from Ecology. Any other information requested b}- Ecology will be submitted �vithin a reasonable time. A copy of the S�'PPP or access to the SVVPPP will be provided to the public �-hen requested in ��riting in accordance with permit condition SS.G. �; Stormwafer Po!lution Prevention Plan i 7.1.4 Updating the SWPPP ' In accordance with Conditions S3, S4.B. and S9.B.3 of the General Permit. this SWPPP will be modified if the SWPPP is ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site or there has been a change in design, construction, operation, or maintenance at the site that has a significant effect on the discharge. or potential for discharge. of pollutants to the �aters of the State. The SWPPP will be modified ��ithin seven days of determination based on inspection(s) that additional or modified BMPs are necessary to correct problems identified, and an updated timeline for BMP implementation will be prepared. 7.2 Reporting ', 7.2.1 Discharge Monitoring Reports ' [Prior to October 2008] If cumulative soil disturbance is smaller than 5 acres: Discharge Monitoring Report (DMR) forms will not be submitted to Ecology because ��ater qualiri� samplin� is not being conducted at the site. If cumulative soil disturbance is 5 acres or larger: Discharge Monitoring Reports (DMRs) will be ' submitted to Ecology monthly. Of there �vas no discharge durin� a given monitoring period. the ', Permittee shall submit the form as required. ��ith the words "'�Io discharge'� entered in the place ' of monitoring results. The DMR due date is 15 da��s follo��ing the end of each month. ', 7.2.2 Notification of Noncompliance If an� of the terms and conditions of the permit are not met. and it causes a threat to human health or the environment, the follo��ing steps ��ill be taken in accordance ��ith permit section SS.F: 1. Ecology ��ill be immediately notified of the failure to comply. 2. Immediate action will be taken to control the noncompliance issue and to correct the problem. If applicable. sampling and analysis of am� noncompliance «-i11 be repeated immediately and the results submitted to Ecology ��ithin five (�) da}s of becomin� a��-are of the violation. 3. A detailed ��ritten report describing the noncompliance ��ill be submitted to Ecology within tive (�) days, unless requested earlier by� Ecology. �6 Stormwater Pollution Prevention Plan ,� Stormwater Po!lution Prevention Plan � � � � ; � _ _i ,- , 28 Stormwater Pollution Prevention P/an 29 Stormwater Po/lution Prevention P1an Appendix A — Site Plans To Be pro�ided B} Contractor 3l Stormwater Pollution Preventron Plan Appe�dix B — Construction BMPs High Visibility Plastic or Metal Fence (BMP C103) Storm Drain Inlet Protection (BMP C220) Temporary and Permanent Seeding (BMP C 120) Plastic Covering (BMP C123) Dust Control (BMP C140) Temporary and Permanent Seeding (BMP C 120) (These Items can be found in the KCSWDM) 32 Stormwater PoJlution Prevention Plan Appendix C — Alternative BMPs The following includes a list of possible alternati�°e BMPs for each of the 12 elements not described in the main SWPPP text. This list can be referenced in the event a BMP for a specific element is not functioning as designed and an alternative BMP needs to be implemented. Element #1 -Mark Clearing Limits Element #2 - Establish Construction Access Flemcnt #� - (��ntr��l Fl�i�. Il,itc• Elc�ncnt #-� - In,t��ll ticdimcnt (�untrul. � _��d��ii�c�d B��1f's: Element#5-Stabilize Soils Element #6- Protect Slopes Element #8-Stabilize Channels and Outlets Element #10 - Control Dewatering Additional Advanced BMPs to Control Dewatering: � 33 Stormwater Pollution Prevention Plan Appendix D — General Permit "Co be obtained b� the Contractor ;; Stormwater Pollution Prevention Plan Appendix E — Site Inspection Forms (and Site Log) The results of each inspection shall be summarized in an inspection report or checklist that is entered into or attached to the site log book. It is suggested that the inspection report or checklist be included in this appendix to keep monitoring and inspection information in one document, but this is optional. However. it is mandatory that this SWPPP and the site inspection forms be kept onsite at all times during construction, and that inspections be performed and documented as outlined below. At a minimum, each inspection report or checklist shall include: a. Inspection date/times b. Weather information: general conditions during inspection, approYimate amount of precipitation since the last inspection. and appro?:imate amount of precipitation within the last 24 hours. c. A summary or list of all BMPs that have been implemented, , including observations of all erosion/sediment control structures or practices. d. The following shall be noted: i. locations of BMPs inspected, ii. locations of BMPs that need maintenance, iii. the reason maintenance is needed, iv. locations of BMPs that failed to operate as designed or intended, and �-. locations ��here additional or different BMPs are needed, and the reason(s) why e. A description of storm��ater discharged from the site. The presence of suspended sediment, turbid water. discoloration, and/or oil sheen shall be noted, as applicable. f. A description of any water quality monitoring performed during inspection, and the results of that monitoring. g. General comments and notes, including a brief description of any B'.VIP r repairs, maintenance or installations made as a result of the inspection. �6 Stormwater Pollutron Prevention Plan h. A statement that, in the judgment of the person conducting the site inspection, the site is either in compliance or out of compliance ��ith the tern�s and conditions of the SVv PPP and the NPDES permit. If the site inspection indicates that the site is out of compliancc. the inspection report shall include a summarv of the remedial actions required to bring the site back into compliance. as ��ell as a schedule of implementation. i. Name. title. and signature of person conducting the site inspection: and the follo��ing statement: "I certifi- under penalty of la«� that this report is true, accurate, and c�mplete. to the best of m� knowled�e and belief'. �'hen the site inspection indicates that the site is not in compliance �vith any terms and conditions of the NPDES permit, the Permittee shall take immediate action(s) to: stop. contain, and clean up the unauthorized discharges, or other�tiise stop the noncompliance: correct the problem(s); implement appropriate Best Management Practices (BMPs). and!or conduct maintenance of existing BMPs; and achieve compliance ��ith all applicable standards and permit conditions. In addition. if the noncompliance causes a , threat to human health or the environment, the Permittee shall comply �ith the '� \oncomplianee I�otitication requirements in Special Condition S�.F of the permit. Stormwater Po!lufion Prevention Plan Site I�spection Form General Information Project Name: Inspector Name: Title: CESCL # : Date: Time: Inspeetion Type: ❑ After a rain e�ent ❑ Week1� ❑ Turbidit}��transparenc}� benchmark exceedance �� ❑ Other Weather Precipitation Since last inspection In last 24 hours Description of General Site Conditions: � Inspection of BMPs Element 1: Mark Cleari►rg Limits BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP � BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP Eleme►it 2: Establisli Construction Access BMP: Inspected Functioning Location y N Y N NIP Problem/Corrective Action BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP 38 Stormwater PoIlution Prevenfion Plan Element 3: Control Flow Rates BMP: Inspected Functionin�� Location y N Y N NIP �''�"��I��» (�,�rr��ti�� ti��n BMP: Inspected Functioning , � , Location Y N Y N NIP I r�,��c��>> (�,,rr.��i�� ti��, Ele»<<�rrl �: /n�tu1l .S��rliiir��ul (��,ntrul� BI�iI' Lucatic�i� ' '�;,��i�.l I �.: �� n �; . , . . Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y '�1 NIP � B�-1P: Location Inspected Functioning problem/Corrective Action Y N Y N '.�IIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP 39 Stormwater Po/lution Prevention Plan Element 5: Stabilize Soils BMP: Inspected Functioning Location y N Y N NIP Problem/Corrective Action BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP Element 6: Protect S/opes BMP: Inspected Functioning Location Y N Y N NIP Problem/Corrective Action ' BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem;'Corrective Action � Y N Y N NIP -to Stormwater Pollution Preventron Plan �i � Element 7: Protect Draifz Inlets BMP: Location Inspected Functioning problem/Correcti`-e Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP B1�1I': ln��«�t��1 I��un�ti��nin�� , Lo�atiuil Y N Y N N1P � ��`'hl�i» (��rr«�ti�� A�ti��n Element 8: Stabilize C/iantaels and Outlets BMP: Inspected Functioning Location Y N Y N NIP Problem/Corrective Action BMP: Location Inspected Functioning problem,'Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP 4l Stormwater Po!lution Prevention Plan � Element 9: Contro!Pollutants BMP: Location Inspect�d Functioning problem�'Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP Elemefat 10: Control Dewatering BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functioning problem/Corrective Action Y N Y N NIP �32 Stormwater Pollution Prevention Plan Storm��ater Dischar es From the Site Observed? Problem/Corrective Action Y❑N Location Turbiditv Discoloration Sheen Location Turbidiri� Discoloration Sheen � � __I i � � , ' - s �__ . � l -13 � Stormwater Po!lution Prevention F Water Qualih' Monitorin Was any water quality monitoring conducted? ❑ Yes ❑ No If water quality monitoring was conducted, record results here: i If�vater quality monitoring indicated turbidity 250 NTU or greater; or transparency 6 cm or less, ��as Ecology notified by phone within 24 hrs? ❑ Yes ❑ No If Ecology was notified, indicate the date, time, contact name and phone number below: Date: Time: Contact Name: Phone #: General Comments and Notes Include BMP re airs. maintenance. or installations made as a result of the ins ection. Were Photos Taken? ❑ Yes ❑ No If hotos taken, describe hotos below: 44 Sformwater Pollution Prevention Plan � ��3��:c�i� F� [� ri<�ii�t�� riri<� { :ilt ��l:itii►��. \�� alculatiun� rcyu�r��i at tl�is tini� f 1 � -i __i � �3� IX. BOND QUANTITY, FACILITY SUMMARIES, AND DECLARATION OF COVENANT A Bond Quantih� Lb'orksheet has Ueen included in this section on the following pages. , A Facilities Summaries Sheet has not been included in this section because there are no water quality or flow �I iontrol devices being installed as part of this project. , A Declaration of Covenant has not been included in this section because there are no water quality or floor II c��ntr�l devices being installed as part of this pmject I COUGHUNPORTERLUNDEEN Renhm�1emorial Sta�iium 13 King County lti�ashingt�,n Site Improvement Bond Quantity Worksheet Webdate 12/02/2008 � King County Department of Development & Environmental Services 900 Oakesdale Avenue Southwest Renton, Washington 98057-5212 For alternate formats, call 206-296-6600. 206-296-6600 TTY 206-296-7217 Project Name: Renton Memorial Stadium �ate: 6/18/2010 �ocation: 405 Logan Ave N, Renton Wa Project No.: Activity No.: Note: All prices include labor, equipment, materials, overhead and Clearing greater than or equal to 5,000 board feet of timber? profit. Prices are from RS Means data adjusted for the Seattle area or from local sources if not included in the RS Means database. yes X no If yes, Forest Practice Permit Number: (RCW 76.09) Page 1 of 9 Unit prices updated: 02/12/02 Version: 11/26/2008 Site Improvement Bond Quantity Worksheet (Section 9).xls Report Date: 6/22/2010 Site Improvement Bond Quantity Worksheet Webdate 12/02/2008 Unit #of Reference# Price Unit Quantity Applications Cost EROSION/SEDIMENT CONTROL Number Backfill & compaction-embankment ESC-1 $ 5.62 CY Check dams, 4" minus rock ESC-2 SWDM 5.4.6.3 $ 67.51 Each Crushed surfacing 1 1/4" minus ESC-3 WSDOT 9-03.9(3) $ 85.45 CY 10 1 855 Ditchin ESC-4 $ 8.08 CY Excavation-bulk ESC-5 $ 1.50 CY Fence, silt ESC-6 SWDM 5.4.3.1 $ 1.38 LF Fence, Temporary(NGPE) ESC-7 $ 1.38 LF , H droseedin ESC-8 SWDM 5.4.2.4 $ 0.59 SY 800 1 472 Jute Mesh ESC-9 SWDM 5.4.2.2 $ 1.45 SY Mulch, by hand, straw, 3"deep ESC-10 SWDM 5.4.2.1 $ 2.01 SY Mulch, by machine, straw, 2"deep ESC-11 SWDM 5.4.2.1 $ 0.53 SY � Pipin , temporar , CPP, 6" ESC-12 $ 10.70 LF Pipin , temporary, CPP, 8" ESC-13 $ 16.10 LF ' Pipin ,temporar , CPP, 12" ESC-14 $ 20.70 LF Plastic coverin , 6mm thick, sandba ed ESC-15 SWDM 5.4.2.3 $ 2.30 SY 100 1 230 Rip Rap, machine placed; slopes ESC-16 WSDOT 9-13.1(2) $ 39.08 CY ', Rock Construction Entrance, 50'x15'x1' ESC-17 SWDM 5.4.4.1 $ 1,464.34 Each Rock Construction Entrance, 100'x15'x1' ESC-18 SWDM 5.4.4.1 $ 2,928.68 Each Sediment ond riser assembl ESC-19 SWDM 5.4.52 $ 1,949.38 Each Sediment trap, 5' high berm ESC-20 SWDM 5.4.5.1 $ 17.91 LF Sed.trap,5'high, riprapped spillway berm section ESC-21 SWDM 5.4.5.1 $ 68.54 LF Seedin , b hand ESC-22 SWDM 5.4.2.4 $ 0.51 SY Sodding, 1"deep, level round ESG23 SWDM 5.4.2.5 $ 6.03 SY Soddin , 1"deep, sloped round ESC-24 SWDM 5.4.2.5 $ 7.45 SY TESC Supervisor ESC-25 $ 74.75 HR 1 20 1495 Water truck, dust control ESC-26 SWDM 5.4.7 $ 97.75 HR 1 10 978 WRITE-IN-ITEMS **** (see paqe 9) Catch Basin Filter Socks $ 300.00 Each 10 1 3000 ESC SUBTOTAL: $ 7,029.00 30% CONTINGENCY&MOBILIZATION: $ 2,108.70 ESC TOTAL: $ 9,137.70 COLUMN: A Page 2 of 9 Unit prices updated: 02/12/02 Version: 11/26/2008 Site Improvement Bond Quantity Worksheet (Section 9).xls Report Date: 6/22/2010 Site Improvement Bond Quantity Worksheet Webdate 12/02/2008 Existing Future Public Private Quantity Completed Right-of-Way Road Improvements Improvements (Bond Reduction)` 8�Draina e Facilities Quant. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Com let Cost GENERAL ITEMS No. Backfill 8 Com action-embankment GI- 1 $ 5 62 CY Backfill&Compaction-trench GI-2 $ 8.53 CY 80 682.40 Clear/Remove Brush,b hand GI-3 $ 0.36 SY 5000 1,800.00 Clearin /Grubbin /Tree Removal GI-4 $ 8,876.16 Acre Excavation-bulk GI-5 $ 1.50 CY 2000 3,000.00 Excavation-Trench GI-6 $ 4.06 CY Fencin ,cedar,6'hi h GI-7 $ 18.55 LF Fencin ,chain link,vin I coated, 6'hi GI-8 $ 13.44 LF Fencin ,chain link, ate,vin I coated, GI-9 $ 1,271.81 Each Fencin ,s lit rail, 3'hi h GI-10 $ 12.12 LF Fill&com act-common barrow GI-11 $ 22.57 CY Fill&com act- ravel base GI-12 $ 25.48 CY Fill&com act-screened to soil GI-13 $ 37.85 CY 100 3,785.00 ! Gabion, 12"dee ,stone filled mesh GI-14 $ 54.31 SY Gabion, 18"deep,stone filled mesh GI-15 $ 74.85 SY Gabion,36"dee ,stone filled mesh GI-16 $ 132 48 SY Gradin ,fine,b hand GI-17 $ 2.02 SY Gradin ,fine,with rader GI-18 $ 0.95 SY 1000 950.00 Monuments,3'lon GI-19 $ 135.13 Each Sensitive Areas Si n GI-20 $ 2.88 Each Soddin , 1"dee ,slo ed round GI-21 $ 7.46 SY Surve in , line& rade GI-22 $ 788.26 Da Surve in , lot location/lines GI-23 $ 1,556.64 Acre Traffic control crew 2 fla ers GI-24 $ 85.18 HR Trail,4"chi ed wood GI-25 $ 7.59 SY Trail,4"crushed cinder GI-26 $ 8.33 SY Trail,4"to course GI-27 $ 8.19 SY Wall, retainin ,concrete GI-28 $ 44.16 SF Wall, rockery GI-29 $ 9.49 SF Page 3 of 9 SUBTOTAL 10,217.40 Unit prices updated 02/12/02 `KCC 27A authorizes only one bond reduction. Version: 11/26/08 Site Improvement Bond Quantitv Worksheet(Section 9).xls . Report Date:6/22/2010 Site Improvement Bond Quantity Worksheet Weodate ,2,��,1008 Existing Future Public Private Bond Reduction" Right-of-way Road Improvements Improvements 8 Draina e Facilities Quant. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Complete Cost ROADIMPROVEMENT No. AC Grindin ,4'wide machine< 1000sy RI- 1 $ 28.00 SY AC Grindin ,4'wide machine 1000-200 RI-2 $ 15.00 SY AC Grindin ,4'wide machine>2000s RI-3 $ 7.00 SY AC Removal/Dis osal/Re air RI-4 $ 67.50 SY Barricade,t e I RI-5 $ 30.03 LF Barricade,t e III Permanent RI-6 $ 45A5 LF Curb&Gutter, rolled RI-7 $ 17.00 LF Curb&Gutter,vertical RI-8 $ 12.50 LF Curb and Gutter,demolition and dispos IRI-9 $ 18.00 LF Curb,extruded as halt RI-10 $ 5.50 LF Curb,extruded concrete RI-11 $ 7.00 LF Sawcut,as halt,3"de th RI-12 $ 1.85 LF Sawcut,concrete, er 1"de th RI- 13 $ 1.69 LF Sealant,as halt RI- 14 $ 1.25 LF Shoulder,AC, (see AC road unit rice RI-15 $ - SY Shoulder, ravel,4"thick RI- 16 $ 15.00 SY Sidewalk,4"thick RI-17 $ 35.00 SY Sidewalk,4"thick,demolition and dis o RI-18 $ 29.50 SY Sidewalk,5"thick RI-19 $ 38.50 SY Sidewalk,5"thick, demolition and dis �o RI-20 $ 37.50 SY Si n, handica RI-21 $ 85.28 Each Stri in , er stall RI-22 $ 5.82 Each Stri in ,thermo lastic, for crosswalk RI-23 $ 2.38 SF Stripin ,4"reflectorized line RI-24 $ 0.25 LF Page 4 of 9 SUBTOTAL I Unit prices updated: 02/12/02 'KCC 27A authorizes only one bond reduction. VersiOn: 11/26/08 Site Improvement Bond Quantity Worksheet(Section 9)xls Report Date: 6/22/2010 Site Improvement Bond Quantity Worksheet Webdate 12/02/2008 Existing Future Public Private Bond Reduction• Right-of-way Road Improvements Improvements &Draina e Facilities Quant. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Complete Cost ROAD SURFACING (4"Rock=2.5 base&1.5"top course) For'93 KCRS(6.5"Rock=5"base&1.5"top course) For KCRS'93, additional 2 5"base ad RS- 1 $ 3 60 SY AC Overla , 1.5"AC R5-2 $ 11.25 SY AC Overla ,2"AC RS-3 $ 15.00 SY AC Road,2",4"rock, First 2500 SY RS-4 $ 21.00 SY AC Road,2",4"rock,Qt .over 2500SY RS-5 $ 19.00 SY AC Road,3",4"rock, First 2500 SY RS-6 $ 23.30 SY AC Road,3",4"rock,Qt .over 2500 S RS-7 $ 21.00 SY AC Road, 5",First 2500 SY RS-8 $ 27.60 SY AC Road, 5",Qt . Over 2500 SY RS-9 $ 25.00 SY AC Road,6",First 2500 SY RS-1 $ 33.10 SY AC Road,6",Qt . Over 2500 SY RS-1 $ 30.00 SY Asphalt Treated Base,4"thick RS- 1 $ 20.00 SY Gravel Road,4"rock, First 2500 SY RS-1 $ 15.00 SY Gravel Road,4"rock,Qt .over 2500 S S-1 $ 8.50 SY PCC Road,5",no base,over 2500 SY S-1 $ 27.00 SY PCC Road, 6", no base,over 2500 SY RS-1 $ 25.50 SY Thickened Ed e RS-1 $ 8 60 LF Page 5 of 9 SUBTOTAL Unit prices updated 02/12/02 'KCC 27A authorizes only one bond reduction. VerSion: 11/26/08 Site Improvement Bond Quantitv Worksheet(Section 9).xls ■ Report Date: 6/22/2010 Site Improvement Bond Quantity Worksheet VVe°da`e ,2,°�;`°°a ' Existing Future Public Private Bond Reduction" Right-of-way Road Improvements Improvements &Draina e Facilities Quant. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Com lete Cost DRAI NAGE (CPP=Corrugated Plastic Pipe,N12 or Equivalent) For Culvert prices, Average of 4'cover was assumed.Assume perforated PVC is same price as solid pipe. Access Road R/D D- 1 � 21.00 SY Bollards-fixed D-2 $ 240.74 Each Bollards-removable D-3 $ 452.34 Each I ' CBs include frame and lid CB T e I D-4 $ 1,257.64 Each 1 1,257.64 CB T e IL D-5 $ 1,433.59 Each CB T e II,48"diameter D-6 $ 2,033.57 Each for additional depth over 4' D-7 $ 436.52 FT CB T e II,54"diameter D-8 $ 2,192.54 Each for additional de th over 4' D-9 $ 486.53 FT CB T e II,60"diameter D-10 $ 2,351.52 Each for additional de th over 4' D- 11 $ 536.54 FT CB T e II,72"diameter D-12 $ 3,212.64 Each for additional de th over 4' D- 13 $ 692.21 FT Throu h-curb Inlet Framework Add D-14 $ 366.09 Each Cleanout, PVC,4" D-15 $ 130.55 Each Cleanout, PVC,6" D-16 $ 174.90 Each 2 349.80 Cleanout, PVC,8" D-17 $ 224.19 Each Culvert, PVC,4" D- 18 $ 8.64 LF Culvert, PVC,6" D-19 $ 12.60 LF 680 8,568.00 Culvert, PVC, 8" D-20 $ 13.33 LF Culvert, PVC, 12" D-21 $ 21.77 LF Culvert,CMP,8" D-22 $ 17.25 LF Culvert,CMP, 12" D-23 $ 26.45 LF Culvert,CMP, 15" D-24 $ 32.73 LF Culvert,CMP, 18" D-25 $ 37.74 LF Culvert,CMP,24" D-26 $ 53.33 LF Culvert,CMP,30" D-27 $ 71.45 LF Culvert,CMP,36" D-28 $ 112.11 LF Culvert,CMP,48" D-29 $ 140.83 LF Culvert,CMP,60" D-30 $ 235.45 LF Culvert,CMP,72" D-31 $ 302.58 LF Page 6 of 9 SUBTOTAL 10,175.44 Unit prices updated: 02/12/02 "KCC 27A authorizes only one bond reduction VerSion: 11/26/08 Site Improvement Bond Quantity Worksheet(Section 9).xls Report Date: 6/22/2010 Site Improvement Bond Quantity Worksheet Webdate ,2,°2,2°°8 Existing Future Public Private Bond Reduction* Right-of-way Road Improvements Improvements DRAINAGE CONTINUED 8 Drainage Facilities Cluant. No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Com let Cost Culvert,Concrete,8" D-32 $ 21.02 LF Culvert,Concrete, 12" D-33 $ 30.05 LF Culvert,Concrete, 15" D-34 $ 37.34 LF Culvert,Concrete, 18" D-35 $ 44.51 LF Culvert,Concrete,24" D-36 $ 61.07 LF Culvert,Concrete,30" D-37 $ 104.18 LF Culvert,Concrete,36" D-38 $ 137.63 LF Culvert,Concrete,42" D-39 $ 158.42 LF Culvert,Concrete,48" D-40 $ 175.94 LF Culvert,CPP,6" D-41 $ 10.70 LF Culvert,CPP,S" D-42 $ 16.10 LF Culvert,CPP, 12" D-43 $ 20.70 LF Culvert,CPP, 15" D-44 $ 23.00 LF Culvert,CPP, 1 S" D-45 $ 27.60 LF Culvert,CPP,24" D-46 $ 36.80 LF Culvert,CPP,30" D-47 $ 48.30 LF Culvert,CPP,36" D-48 $ 55.20 LF Ditchin D-49 $ 8.08 CY Flow Dis ersal Trench 1,436 base+ D-50 $ 25.99 LF French Drain 3'de th D-51 $ 22.60 LF Geotextile, laid in trench, ol ro lene D-52 $ 2.40 SY Infiltration ond testin D-53 $ 74.75 HR Mid-tank Access Riser,48"dia, 6'dee D-54 $ 1,605.40 Each Pond Overflow S illwa D-55 $ 14.01 SY Restrictor/Oil Se arator, 12" D-56 $ 1,045.19 Each Restrictor/Oil Se arator, 15" D-57 $ 1,095.56 Each Restrictor/Oil Se arator, 18" D-58 $ 1,146.16 Each Ri ra , laced D-59 $ 39.08 CY Tank End Reducer 36"diameter D-60 $ 1,000.50 Each Trash Rack, 12" D-61 $ 211.97 Each Trash Rack, 15" D-62 $ 237.27 Each Trash Rack, 18" D-63 $ 268.89 Each Trash Rack,21" D-64 $ 306.84 Each Page 7 of 9 SUBTOTAL Unit prices updated: 02/12/02 'KCC 27A authorizes only one bond reduction VersiOn: 11/26/08 Site Improvement Bond Quantity Worksheet(Section 9).xls Report Date: 6/22/2010 Site Improvement Bond Quantity Worksheet Webdate 12/02/2008 Existing Future Public Private Bond Reduction' '� Right-of-way Road Improvements Improvements 8 Draina e Facilities Quant. Unit Price Unit Quant. Price Quant. Cost Quant. Cost Com let Cost PARKING LOT SURFACING No. 2"AC,2"to course rock&4"borrow PL-1 $ 21.00 SY 2"AC, 1.5" top course&2.5"base cou PL-2 $ 28.00 SY 4"select borrow PL-3 $ 4.55 SY 1.5"to course rock&2 5"base course PL-4 $ 11.41 SY UTILITY POLES 8�STREET LIGHTING Utilit pole relocation costs must be accompanied b ranchise Utili 's Cost Statement Utilit Pole s Relocatfon UP-1 Lum Sum � Street Li ht Poles w/Luminaires UP-2 Each � WRITE-IN-ITEMS Such as detention/water ualit vaults.) No I WI-1 Each WI-2 SY WI-3 CY WI-4 LF WI-5 FT WI-6 WI-7 WI-8 ! WI-9 �� wi in SUBTOTAL SUBTOTAL(SUM ALL PAGES): 20,392.84 30%CONTINGENCY&MOBILIZATION: 6,117.85 GRANDTOTAL: 26,510.69 COLUMN: B C D E Page 8 of 9 Unit prices updated: 02/12/02 "KCC 27A authorizes only one bond reduction Version 11/26/OS Site Improvement Bond Quantity Worksheet(Section 9)xls Report Date: 6/22/2010 � Site Improvement Bond Quantity Worksheet Webda'e 'Z,°Z,Z°°8 Original bond computations prepared by: Name: Sean Robertson oate: 6/18/2010 PE Registration Number: 46000 Tel.#: 206-343-0460 Firm Name: Coughlin Porter Lundeen Address: 413 Pine St, Suite 300, Seattle 98199 Project No: ROAD IMPROVEMENTS 8 DRAINAGE FACILITIES FINANCIAL GUARANTEE REQUIREMENTS PERFORMANCE BOND` PUBLIC ROAD&DRAINAGE AMOUNT BOND'AMOUNT MAINTENANCE/DEFECT BOND` REQUIRED AT RECORDING OR Stabilization/Erosion Sediment Control (ESC) (A) $ 9,137.7 TEMPORARY OCCUPANCY'"" Existing Right-of-Way Improvements (B) $ - Future Public Road Improvements 8�Drainage Facilitie (C) $ - Private Improvements (D) $ 26,510.7 Calculated Quantity Completed (E) $ - Total Right-of Way and/or Site Restoration Bond"/** (A+B) $ 9,137.7 (First$7,500 of bond'shall be cash. PerFormance Bond'Amount (A+B+C+D) = TOTAL (T) $ 35,648.4 T x 0.30 $ 10,694.5 OR inimum on amount is Reduced Performance Bond'Total ""* (T-E) $ 35,648.4 Use larger o x o or - (B+C) X MaintenancelDefect Bond'Total 0.25= $ - NAME OF PERSON PREPARING BOND"REDUCTION: Date: 'NOTE: The word"bond"as used in this document means any financial guarantee acceptable to King County. ""NOTE: KCC 27A authorizes right of way and site restoration bonds to be combined when both are required The restoration requirement shall include the total cost for all TESC as a minimum,not a maximum. In addition, corrective work,both on-and off-site needs to be included. Quantities shall reflect worse case scenarios not just minimum requirements. For example, if a salmonid stream may be damaged,some estimated costs for restoration needs to be reflected in this amount. The 30%contingency and mobilization costs are computed in thfs quantity. ***NOTE: Per KCC 27A,total bond amounts remaining after reduction shall not be less than 30%of the original amount(T)or as revised by major design changes. SURETY BOND RIDER NOTE If a bond rider is used.minimum additional performance bond shall be $ 26,510.7 (C+D)-E REQUIRED BOND`AMOUNTS ARE SUBJECT TO REVIEW AND MODIFICATION BY DDES Page 9 of 9 Unit prices updated: 02/12/02 Check out the DDES Web site at www.kinpcountv.qov/permits Version: 11/26/08 Site Improvement Bond Quantity Worksheet (Section 9).xls Report Date: 6/22/2010 � X. OPERATION AND MAINTENANCE MANUAL Standard Maintenance Per standards set forth in the King County Surface Water Design I�-lanual,the owner will maintain facilities. Sections of the King Couni��Storm Water Management Design Manual outlining the Operations and '�laintenance of these facilities have been included in this section on the follo�ving pages. � � ��I ! I, (_ MAINTENANCE STANDARDS FOR PRIVATELY MAINTAINED DRAINAGE FACILITIES AT RENTON MEMORIAL STADIUM I NO. 1 -CATCH BASINS Maintenance Defect Conditions When Maintenance is Results Expected When Component Needed Maintenance is performed General Trash& Trash or debris of more than 1/2 cuhic iVro Trash or debris Debris foot which is located immediately in front located immediatel� in (Includes of the catch basin opening or is blocking front of catch basin Sediment) capacin�of the basin by more than 10°0 openu��;. Trash or debris(in the basin)thatexceeds No trash�,r�1��i��is in th�� 1/3 the depth from the bottom of basin t�� c�tch I��in lri�'e1't tll�'l�i��c'St�ii��t int�i��i'r�nt��f tl�� Uasin. TI'c1S11 ��i .,i��'f'. I�1 „ , II .��t �i � ;!�_.�� . .. �'ll•,'t .11i�� :Itlt'f ��I��i � 1-' I ��i�i ,Iilllii.il5 ��I �.��<ll��ii �ii.ti��ui�i .\�� l�-��i :tiliiil.li� generate odors thatcould cause vegetation present � complaints or dangerous gases(e.g., w ithin the catch basu�. methane). Deposits of garbage exceeding 1 cubic No condition present foot in volume which would attract or support the rreeding of insects or rodents. Structure Corner of frame extends more than 3/4 Frame is even with curU. Damage to inch past curb face into the street(If Frame and/or applicable). Top Slab Top slab has holes larger than 2 square Top slaU is free of holes inches or cracks wider than 1/4 inch and cracks. (intent is to make sure all material is running into basin). Frame not sitting flush on top slab,i.e., Frame is sitting flush on separation of more than 3/-�inch of the top slab. frame from the top slab. COUGHLINPORTERLUNDEEN Rrntc�n�lemurial5ta�liLnt� 1 fi King Cow�h'l�Vashington NO. 1 -CATCH BASINS (CONTINUED) Maintenance Defect Condition When Maintenance is Results Expected Components Needed When Maintenance is Performed. Gacks in Basin Cracks�tirider than 1/2 inch and longer Basin replaced or Walls/ Bottom than 3 feet,any evidence of soil repaired to design particles entering catch basin through standards. cracks,or maintenance person judges that structure is unsound. Cracks wider than 1/2 inch and longer No cracks mare than than 1 foot at the joint of any inlet/ 1/4 inch wide at the outlet pipe or an`�evidence of soil joint of inlet/oudet ' particles entering catch basin through pipe. cracks. Sediment/ Basin has settled more than 1 inch or Basin replaced or Misalignment has rotated more than 2 inches out of repaired to design alignment. standards. Fire Hazard Presence of chemicals such as natural No flammable gas,oil and gasoline. chemicals present. Vegetation Vegetation growing across and No vegetation blocking blocking more than 10°%of the Uasin opening to basin. opening. Vegetation gro��ing in inlet/outlet pipe No vegetation or root joints that is more than six inches tall growth present. and less than six inches apart. Pollution Nonflammable chemicals of more than No pollution present 1/2 cubic foot per three feet of basin other than surface film. length. Catch Basin Cover Not in Cover is missing or only partially in Catch basin cover is Cover Place place.Anv open catch basin requires closed maintenance. Locking 1��lechanism cannot be opened Uy on Mechanism opens�vith I�'Iechanism maintenance person with proper tooLs. proper tools. Not�ti'orking Bolts into frame have less than 1/2 inch of thread. Cover Difficult One maintenance person cannot Cover can be removed to Remove remove lid after appl��ing SO lbs.of lift; b}'one maintenance intent is keep cover from sealing off person. access to maintenance. Ladder Ladder Rungs Ladder is unsafe due to missing rungs, Ladder meets design Unsafe misalignment,rust,cracks,or sharp standards and allows COUGHLINPORTERLUNDEEN Renton b4emorial Sta��ium 17 King Counh�Washington edges. maintenance person safe access. Metal Grates Grate with opening wider than 7/8 Grate opening meets (If Applicable) inch. design stanc�ards. Trash and Trash and debris that is blocking more Grate free of trash and Debris than 20% of grate surface. debris. Damaged or Grate missing or broken member(s)of Grate is in place and Missing. the grate. meets design standards. NO. 2 - ENERGY DISSIPATERS Maintenance Defect Conditions When Maintenance is Results Expected When Components Needed Maintenance is Performed. Manhole/ VVorn or Structure dissipating flow Replace structure to Chamber Damaged deteriorates to 1/2 or original size or design standards. Post.Baffles, any concentrated �vorn spot Side of exceeding one square foot w•hich Chamber �vould make slructure unsound. Other Defects See"Catch Basins"Standard No.� See"Catch Basins" Standard :�o.-� � COUGHLINPORTERLUNDEEN Renton hfem��rial Stadium 18 King Cow�h 11`as}ti�gton r __— --- - — NO. 3 - FENCING Maintenance Defect Conditions When 1�4aintenance is Results Expected When Components Needed Maintenance is Performed General Missing or Any defect in the fence that permits Parts in place to provide Broken Parts eas��entrv to a facility. adequate securitv. Erosion Erosion more than�inches high and No opening under the 72-18 inches wide permitting an fence that exceeds-� opening under a fence. inches in height. Wire Fences Damaged Post out of plumb more than 6 inches. Post plumb t��ithin 1- Parts 1/2 inches. Top rails bent more than 6 inches. Top rail free of bends greater d�an 7 inch. Any part of fence(induding post,top Fence is aligned and rails)more than 1 foot out of design meets design standards. alignment. �lissing or loose tension�vire. Tension wire in place and holding fabric. Extension arm missing,broken,or Extension arm in place bent out of shape more than 1 1/2 with no t�nds larger inches. than �/-1 inch. Deteriorated Part or parts that have a rusting or Structurall��adeyuate Paint or scaling condition that has affected posts or parts�vith a Protective structural adeyuacy. uniform protective Coating coating. COUGHLINPORTERLUNDEEN Renton�4emi�rial Stadium 19 King Counh�11'a�hingtc�n NO. 4-GATES Maintenance Defect Conditions When Maintenance is Results Expected Component Needed When Maintenance is Performed General I�amaged or I�lissing gate or locking devices. Gates and Locking �4issing devices in place. �lembers Broken or missing hinges such that Hinges intact and gate cannot be easily opened and lubed.Gate is�vorking closed b��a maintenance person. freely. Gate is out of plumb more than 6 Gate is aligned and inches and more than 1 foot out of vertical. design alignment. tilissing stretcher bar,stretcher Stretcher bar,bands bands,and ties. and ties in place. Openings in See"Fencing" Standard No.i See"Fencing"Standard Fabric V o. 7 NO. 5 -CONVEYANCE SYSTEMS (PIPES 8� DITCHES) i Maintenance Defect Condidons When Maintenance is Results Expected When �i Component Needed Maintenance is � Performed I Pipes Sediment& Accumulated sediment that exceeds Pipe cleane�i of all � Debris ?0°0 of the diameter of the pipe. sediment and debris. Vegetation �'egetation that reduces free All vegetation remove�l movement of water through pipes. so�vater f]ows freel�� through pipes. Damaged Protective coating is damaged;rust is Pipe repaired or causing more than�0°o deterioration replaced. to any part of pipe. Anv dent that decreases the cross Pipe repaired or section area of pipe b�� more than replaced. ?peo. � Open Ditches Trash& Trash and debris exceeds 1 cubic foc�t Trash and �lebris Debris per 1,000 syuare feet c�f ditch an�1 ileared from ciitches. slopes. Sediment Accumulated sediment that exceeds Ditch cleaned/ t7ushe�l 20 °�o of the design depth. of all sediment and debris sc�that it matchts design. Vegetation Vegetation that reduces free 41�'ater flc��s freel� mo��ement of water throu�h ditches. through ditches. COUGHLINPORTERLUNDEEN Rrnt��n\trnu�ri�il�ta�lium �l� I�in�;C��unh 1\a�hin�;hm Erosion See"R�in gardens" Standard�Io.l See"Rain gardens" Damage to Standard No.1 Slopes Rock Lining 1�laintenance person can see native Replace rocks to design Out of Place or soil beneath the rock lining. standards. hlissing(If Applicable). Catch Basins See"Catch Basins:Standard No.�k See"Catch Basins" Standard No.4 Debris See"Debris Barriers"Standard No.S See"Debris Barriers" Barriers(e.g., Standard No.5 Trash Rack) NO. 6 -GROUNDS (LANDSCAPING) Maintenance Defect Conditions When Maintenance is Results Expected When Component Needed Maintenance is Performed General Weeds 41'eeds growing in more than 20°b of Weeds present in less (Nonpoisonou the landscaped area(trees and shrubs than 5°0 of the s) only). landscaped area. Safety Hazard Any presence of poison i�y or other No poisonous vegetaHon poisonous vegetation. present in landscaped area. Trash or Litter Paper,cans,bottles,totaling more than Area clear of litter. 1 cubic foot w�ithin a landscaped area (trees and shruUs onl��)of 1,000 square feet. Trees and Damaged Limbs or parts of trees or shruUs that Trees and shrubs with Shrubs are split or Uroken��hich affect mare less than 5°0 of total than 25°o of the total foliage of the tree foliage with split or or shrub. Uroken limbs. Trees or shrubs that have been blo�ti-n Tree or shrub in place do�vn or knocked over. free of injury. Trees or shrubs which are not Tree or shruU in place adequately supported or are leaning and adequately over,causing exposure of the roots. supported;remove any dead or diseased trees. COUGHLINPORTERLUNDEEN Renton Memorial Stadium 21 King C�unh'Washington N0. 7 -ACCESS ROADS/EASEMENTS Maintenance Defect Condition When Maintenance is Results Expected Component Needed When Maintenance is Performed General Trash and Trash and debris exceeds 1 cubic Roadway free of debris Debris foot per 1,000 square feet i.e., trash which could damage and debris would fill up one tires. stanaards size garbage can. Blocked Debris which could damage vehicle Roadwav free of debris Road�n�ay tires (glass or metal). �rhich could damage tires. Anv obstruction which reduces Roadwav overhead dearance aUove road surface to less clear to 14 feet high. than 14 feet. Any obstruction restricting the Obstruction removed access to a 10 to 12 foot width for a to allow at least a 12 distance of more than 12 feet or an�� foc�t access. point restrictin�access t� less than a 10 foot w�atr►. Road Surface Settlement, �-ti'hen any surface aefect exceeds 6 Rc�a�� surface Potholes, inches in aepth and 6 square feet in uniforml��smooth I�iush Spots, area. In general,any surface defect ti�ith no evidence��f Ruts �vhich hinders ar prevents settlement, pothol��, maintenance access. mush spots,or ruts. Vegetation in �1�'eeds gro��ing in the ruaa surface Road surface free�,f Road Surface that are more than 6 inches tall and weeds taller than ? less than 6 inches tall ana less than incht s. 6 inches apart within a�00-syuare fc�c�t area. COUGHLINPORTERLUNDEEN Rcntc�n'�trmnri.il Sta�lium �� hin�;C��unh 1\�i�h�nr;t��n