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HomeMy WebLinkAboutPermit File BLD-2023-0058 1918 Bay Place (4) r °f o Yk rm Water Drainag Repa ort i � m M ti U, a � Minimum Requirement #2 b C 0 „ ENGINEERING DEPARTMENT 904 6t" Street Anacortes, WA 98221 www.anacorteswa.gov Official Use Only: (Information to Inspectors) Required Storm Water Facility and other related requirements: Project Address: 1918 Bay PI Submittal Date: 2/2/23 Parcel Number: P59622 Revision Number: Permit Number: BLD-2023-0058 Reviewer: Rob F Acceptance Date (COA): 2/7/23 FRONT OF REPORT: Submittal Checklist: (All items listed below are required for a complete submittal) o Cover Sheet (Preparer to Provide): Project title, Location, Revision dates, Engineer's Stamp o TAB 1: Minimum Requirement#1 — Preparation of Stormwater Site Plans o TAB 2: Minimum Requirement#2 —Construction Stormwater Pollution Prevention (SWPP) o APPENDIX 1 - Survey performed by a Professional Land Surveyor o APPENDIX 3 - Model Soil Management Plan for BMP T5.13 o APPENDIX 4 - Determining Construction Site Sediment Damage Potential (Appendix 7) o APPENDIX 5 - Site Plan with all applicable information (Minimum Size 11 x17 — 30 scale) o APPENDIX 6 - Documented Site Photos (North, South, East and West) Stormwater Management Requirements: o Refer to the 2019 Department of Ecology Manual o See also, City of Anacortes Municipal Code 19.76 for additional information o See also, current Engineering Development Standards, Chapter 2- Storm Drainage for additional information. Version Date: August 30, 2022 Project Description and Summary: Summary Table Existing Proposed Development Type Residential Landscape Number of Lots 1 Lot Acreage in SF 18295.20 Soil Type(s) Artificial Fill Site Sediment Transport Score Hi h\Low Low -45 Depth to Ground Water Table (Feet and Inches) See completed Soils Analysis Volume 1, Chapter 3.1.1 Flow control Exempt Infiltration Rate during Rainy Season Inch\Per Hour Impervious Surface on-site 7,036sf 6 342sf Impervious Surface off-site 0 0 New and Replaced Hard Surface Total SF 3 157 Lot Coverage (Percentage) 15.4% 16.9% BMP (Required Minimum Requirement 5) BMP T5.13 Post Construction Soils Water Quality Method Minimum Requirement 6 Below threshold Water Quantity Method Minimum Requirement 7 Below threshold Existing Site Conditions Summary: (Additionally, provide information on previous permits, if any, like Grade and Fill, Clear and Grade, topography, vegetation, drainage, Critical Areas adjacent to the site and how it may affect this project if soils are disturbed, Soils Type (Included in Soils Analysis Report), Erosion Problem Areas, Construction Phasing)Sequence) On the lot there is an existing single family home and attached garage with a total impervious area of 3,356 sf. The existing driveway covers 1,078sf and the sidewalk/patio area covers 2,602sf. The road frontage has an existing curb but no sidewalk. The closest catch basin is 260 feet to the north on Bay Place. No soils report was completed for this site. Developed Conditions Summary: (Additionally, to be shown on the site plan. Identify cut and fill areas, proposed slopes of all hard surfaces , proposed contours) The proposal is to replace 3,157sf of concrete with new landscaping, new driveway, and pathways and construct a new patio cover that will cover 320sf of area. Drainage Basin (2007 Storm Comp Plan — City website\publicworks\engineering\comprehensive plans): What Drainage Basin are you in? n/a Identify any downstream drainage issues (Storm Comp Plan: Yes If so, describe: The site is adjacent to and directly discharges into Flounder Bay. Complete the Applicability Requirements — Flow Chart (See next page(s) - Highlight the path and attach Version Date: August 30, 2022 itart e �� develgp eII t PIr legit III Its h a v e °' Ives ��� T h r�mm sIII iI I I"Ir'lI,( g r�� " �-tol or mtorle of I ml„I I IIIIIII N` 11 IIiI •gym Char �u� J� y u, a fl dl I� dl V IV a Il ri c c,aI MY" r�r�MM � Prrry �I b l J V J r, II ""N� 0 o II III t.J W """� ,"W IIIAW IW 41°® �'I'1 NO Does, the j r °fit n- ��I�y, t w m III eil� Does Illf I Project ��� I�I��m�Y�I1�I'r I��I,,, lawn I, r Jllun a 11 I, 'i1L.1R'IW�II III�.p u N S .III r h��our ofI `0 r feet i i �� urI�IM° r ator, of niew p4sIi""iia lv v egaeLationL p. t IIIII,trie hia.,,r surface, MII f II�IIIr III I1. MI I�I MMI� Y' es Ves I�IIdIIIRu III IN ss the Ir jI �w Ir sf It III �r0(, ar feet r` �MII VI I ml�,� f �r III �. �� nlu I�M �Jd V,; „�I ��I I I%� �a III r. InI ; ,fie II ,II in p ly 'W'th IInew aiidr l la 1'l l If c), s a d I III - I i r I mll� f i I vegelati ; I( W I m�� ', I, 0 mllld «I ,estJ I II Rrolject llialve, I ndl � ilw Il i � i i t IIII,II II � I juait IIIII I��I � ni , P I 'through I h I I II III It,o Ir W ra teer Vies amid rqplaced hard wirfaceas and the, II I , i Ir . II �I II II uim Re . i Il,r m n p p les, �Flow pp far .. I}r I InIReq IIII I far .............I................................................I.......... I'M New Devel Po milent, PIP.............................. W �'iu ,y��I,�III A T �Y��»'�N II�Yf�� III �Y,w �f )° i, ��l ECOLOGY leaI m ,:' W,,OC � l w � rV/ nxT, copyrightn (I mt, I nd In ; , mls IIo W JV II II MINI �.ICI; I� f W II h I n I�t ii m(I µ �, ,t�f 0' Pry. ���c,� � II �w � W Py Y IVI bC Version Date: August 30, 2022 Docfa:s,the Prc'i, 1, I d hi�.i,rt.,.l 8 u, c e a 67 jjet-t result In 2,,0101U, squia,r LN,,, fee,t, o�r more,,,, of oew plus re ,0 R, Does the, di'Shikt'bin i Ry total 7,000 %IIIIII liaare felei..![ ol,,,,r gm,,;a,4e.,).r`7. es F I V, i No i n i m u m Re q u ire.mmi,e n ts #1 1,1111 r,O u,,,'g,h #5 appI y t the nie, ,, and m p, I�w ,��pl auQ,,d ha�r;d Minbrum, Requirement,#21 a! plies■ A,.,nd fl,--i e l atn�ti, Next, Ovei�,stl on Does thle Project add 5,,0100 squiare feet or,mI e,,o,f new, hj,aird siuirfayes? OR,, C;0�1'1,ve)41",% aowc�res,,;, olir more, 'to Wwrli� or ]OR CcIrtve-rt, or mcre of maative ve!,,geta,t1fj&f1, to paas,ture? V111 IF No All Minkynum Rvqulr&�metits apply Next Ouestion, Is,, th1s, ra, roarl to'the ne�w ha�rdl s,uvrf ces and the re[ated pro, No COI!Veitt",� I' II I. Ilareas,,,, D',,0leS the Projemctt, �.,,.,iidld 5�00,0 squiare, f"eect or rii�Dteof rie,, 11 Nat surlAtes? S, Av ",,a m ; 0 1 510 , I mph n oz,� ip I u s re,p I c d ,1,a ri,I smil'i'd-acems" .9. )0 or rn(T)r0,,,, �rho the Vi"iiew ANI), s,��i jrtaces addfi, 610% or, No No ck"") "t h,1110, v la,1 01o, o F,t 1)o PTm-p n,,vp,rov 011 s,,-- No lad4ftlointia] fe mor rl,o to t h lie e x s:t I re mmenit,vallum, f ass"IeSq--ed value Wi I avm reqju I ree m entsil. I F 0 0 Ihfc,: the S I xW111nig RrQ1 0"', 111,1.,111te, I c mmn rcpl, I ot, ODRK, exIst[rig h,",nprrove,,mc i",�,vt S(f a I I 1"i e r p rt ctict),.0 ................ Ali Minimum Requirements ap�, 1y to the new and replac,40dl YII es, Vies' 10 haird surt,aices,ar,)d ,co��nve��rted"� vegeftlaxtIon w Ghartfdr Dete rmining Requ Flo f6r i re e�,nts-, Redevelopment .............................. Revlse a ch 20,19 D E P111 A RT M E N 1.T ECOLOGY !"JIM11V"fro,"c pyright notIce Includ Ing pw,,rnilssflions,m 1�fflllb I k Tr ��t 0 n I I rr I ta 1,1 o b I I I d Sta�lle of Washlngtonlil Version Date: August 30, 2022 TAB 2 (MINIMUM REQUIREMENT#2) 1-3.4.2 Minimum Requirement#2 — Construction Stormwater Pollution Prevention Plan (SWPP) All new development and redevelopment projects are responsible for preventing erosion and discharge of sediment and other pollutants into receiving waters. Projects which result in 2,000 square feet or more of new plus replaced hard surface area, or which disturb 7,000 square feet or more of land must prepare a Construction Stormwater Pollution Prevention Plan (SWPPP) as part of the Stormwater Site Plan (see MR1: Preparation of Stormwater Site Plans). Projects below those thresholds (listed above) are not required to prepare a Construction SWPPP, but must consider all of the Construction SWPPP Elements (listed below) and develop controls for all Construction SWPPP Elements that pertain to the project site. General Requirements: The Construction SWPPP shall include a narrative and drawings. All BMPs shall be clearly referenced in the narrative and marked on the drawings. The Construction SWPPP narrative shall include documentation to explain and justify the pollution prevention decisions made for the project. Each of the 13 Construction SWPPP Elements (listed below) must be considered and included in the Construction SWPPP unless site conditions render the Element unnecessary and the exemption from that Element is clearly justified in the narrative of the SWPPP. Clearing and grading activities for developments shall be permitted only if conducted pursuant to an approved site development plan (e.g., subdivision approval) that establishes permitted areas of clearing, grading, cutting, and filling. These permitted clearing and grading areas and any other areas required to preserve critical or sensitive areas, buffers, native growth protection easements, or tree retention areas, shall be delineated on the site plans and the development site. The Construction SWPPP shall be implemented beginning with initial land disturbance and until final stabilization. Sediment and Erosion control BMPs shall be consistent with the BMPs contained in II-3 Construction Stormwater BMPs. Seasonal Work 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 will be prevented from leaving the site through a combination of the following: 1. Site conditions including existing vegetative coverage, slope, soil type and proximity to receiving waters; and 2. Limitations on activities and the extent of disturbed areas; and 3. Proposed erosion and sediment control measures. The following activities are exempt from the seasonal clearing and grading limitations: 1. Routine maintenance and necessary repair of erosion and sediment control BMPs, 2. 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 3. Activities where there is one hundred percent infiltration of surface water runoff within the site in approved and installed erosion and sediment control facilities. Version Date: August 30, 2022 ullanstruz" Jon, S ,arm�water Pdllulian Prevention PlIan, Checkfll�st C"-ty Referenc Na. p"J" ticmn R—exla,,,,i a t,,,e,-- On-smicte" fil. t on"Rell i ew,Diat"e-- 6T. ef- ievv c 1 1]C"101-tst]" t� e� SIN't"T"PIP C', sti"mct,on pooll ti ii ,11PIrilin ,�, doil"ll El Imei ts 1 Describe h,ow e�ach.of the C'�Mstnictioil Ston ��a t,,,e,:r an Elemm, s. h a s bem addresssed fli,ou l7un s.,tn5,, iT g ct im SIV,PP- ,)I,i tl C,� 2 Identlify tlie, ty ' ro a t pe,amd'I C,, on Of BNEPs-itltsed top satiss', fl.,ie re el en ,,3,,,. Pronvide,'wn tten jill'us,"t illlflilllccla t on iideivtIllf�i ng,, �,,t e,reanisoll an el�mw.,,,nt lis,noopt '.1pplic,aable"too t"Ile propousa Oflu I 111111110111f, "P T "tirteen. Requ�u: d q2 "t,,,S 1 j C-,',l cummilg"L,' "'t s,; 2 .1i,Coilstn,iction Access Col,itrol'"Row, 4. 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'a s- Ul'I 1,011 d L I 9 ba Sl IIS"." .. L a,"b ,1 E,u n I gade,,,contours, ,"'Idel if�-�derA.,elopted. dmL�IM ge' 10.. Delu­ ieate ani-ean tliat a;i-e"too be cle-u I a :-,iaded. u.�i�g top and bo,tton"i of'sloper,ctitcb,lu"i cs".Show,a 1 1 civit -m�id,fil 1 slopes u­.�idica t" 'I lies oT��ditc.��Itercep" tor trenx,,Iles,�, ma g 2 Show,a 1 1 te, n a mwy nd,,perm.-ml ent'dni pipes, Ill t"ClIe-IS OT Cllt'-Olff'trelld'l re,cpu I red coltol... ffll,f lo,fa�'j-j 0 veltss- 3.. Prooln"'de,nul"Um", slope covef r a 11, "p M"or Ca I'l Out Pipe Ur 'I fl � I s,', -m�id'I'S of"f owi, U' a 11,ditd,.les,; sixva le,,,,,s cWT L 4. Sliow� dm, m L 7 7 pillpe" . 1151". ]PIrooln"',&.I&.ltaalls i ui io iOff-ssa I le numo• ff S 6. hiditcate, localtiaill,I al Ouftl etts"of au sys"'t elm- s Ljmlla"t ni of Dete-',.1,11, ie,ll- 1 Ident ltlllf�v loc,tqmtion,o f'detent lon"IBN UMI"Ss. R±7vl�sed Febmm- 2 Version Date: August 30, 2022 ]� UU, L � � � L' �' @ N,� �s • ®n pipes, �how, a c. Y . id,Du' n �r® �II 1,o� u "1 benn W� . �"� uo� NN. �rl f Wt w.,s,;� V �i,u �m�., u ° idi vi I I L II o°,�' 11( II r �� the a II II r�u,' u d'a I� uu �ii u i • yam , i y� �y(r,I �y� u y 1 �y, �y� ® h cat t la ' 8 1 ,a J k��.0 h„VIW..L`k� N� 3�" 3.,, .,, yL'�• 1 J 6s,. 1 �I�° r�r III •���q ,n y � •���q 1� I'd��I+�Ip,����������I,�p�1� 1 „"'��� �1K:lu"'AIII(',"i�� ,w'u L 'N L ���YIW��� IVY �N ���� ���1K:lu"' AIL '� ��� u� f ���IV� RLu"I s�R�� „t��'NI�f;JYf„"'"Ls�R` ;mlRii .n. ������ ! 7r f J4, 1 III I II I r II I, IVY. t' u �u w � �� �i� ��� ����� rl� �������11 If �� 1 �� � ��I t ' �L&o� If th,� 1 � � ,' dev .. ilu Detzal,sta Y'1 Iza."doll 6 "W�.�^I 1Y�1 "MA:wI„.VII e.wl"t7. Detmil c�ol&o L' locati onm detaill s- u, I&l or �lt ddl riif s® w ® CI I � m � I � Lrock, i i o � f� 1����.1 � ��. I� �' IIII i.n � � w' NI L t[ I r, NIL I�`i U I Y.uU I°.w 1 L Prov(7,,,',ide,,,Erontw, oftypnical rock c eI ,s m ,,,. II YI �� I�,"° ,��, III r, u�. ��� u���,,�1° IIY II r I� IIII r, r;u,,�.n DIY- [Ica � c,a io I t N-""�� ��l We�^ ( rl, tuNL w��� w Yr�L�'���� i"1YL��li'�1 t,Io �� � �����',t� �10 II�'�'�'.n ate �� , �� .n .r .n ��'� � A II� � �If��1 ',� `'a„� 11f���� rl w''t��L u II�.. °°�,� IIII r� ,, II a Ih, ®n �� YI � r, ® t �Y 1� a re r N L 1 s L e with r v"'III S lll® X EP,"Is II ,' � IIY''u u u �,�. °', IL i IIY � �r, Ih I u control,IL I r, ® N the,,,N e If � If � N t it f 1 , �>�If � � n II YI IIY'u � IIY III N� IIY IVY�_ [I 'N ..;. ��,.��� �Lw'N i; '���d,'in ��� �u � I�, a ra'�' •L'��� Y�'L ,,:: �";NI 'N e��� lg i o "1 1 't,, ��� ��� top.p ,, 's JY L� f � I moin, flie ���. ®n � ,..��� IVY. IV�IhN Y u��. u � � 1 rr� "hl� 's �:,;m�WW I'M ., YL ����LL IV .I....'....® I Y. Re',,v' ed Fe,bmm- s 2 J „ Version Date: August 30, 2022 13 Elements of SWPPP (Construction Stormwater Pollution Prevention Plan) Please check off boxes to show that each element has been read and understood. Provide details where applicable and if certain aspects are unnecessary or exempt, clearly justify. Details of the 13 Elements and the correlating BMPs are listed Above from the 2019 Stormwater Management Manual for Western Washington (SWMMWW). A link is provided on the City of Anacortes website, under Planning, Community, & Economic Development Department, as well as under Stormwater on the Engineering Division of Public Work's page. Owner Name: Sandra Russell Site Address: 1918 Bay Place Prepared By: ANC Design - Aaron Parrish The Stormwater checklist or building permit determined that: ❑ The 13 elements must be addressed ❑ These elements must be addressed for construction activity adding under for construction activity adding 2,000 2,000 sq. ft. of hard surface area. sq. ft. or more of hard surface area. This means that an attached narrative and site plan are required with this document. Under each element, provide the BMP's that will be applicable to your project. Use the attached Tables provided. ELEMENT 1: Preserve Vegetation/Mark Clearing Limits ❑ Before beginning land disturbing activities, including clearing and grading, clearly mark all clearing limits, sensitive areas and their buffers, and trees that are to be preserved within the construction area. ❑ Retain the duff layer, native top soil, and natural vegetation in an undisturbed state to the maximum degree practical. Suggested BMPs for Element 1: BMP C101: Preserving Natural Vegetation BMP C102: Buffer Zones BMP C103: High-Visibility Fence • BMP C233: Silt Fence How did you comply with this section? A high visibility construction fence BMP C103 will be installed at the perimeter of the construction site except if an existing fence already exists or were silt fence is used. BMP will be installed as first step ot construction. BMP to be monitored daily and repaired as needed. Version Date: August 30, 2022 ELEMENT 2: Establish Construction Access ❑ Limit construction vehicle access and exit to one route, if possible. ❑ Stabilize access points with a pad of quarry spalls, crushed rock, or other equivalent BMPs, to minimize tracking onto roads. ❑ Locate wheel wash or tire baths on site, if the stabilized construction entrance is not effective in preventing tracking sediment onto roads. ❑ If sediment is tracked off site, clean the affected roadway thoroughly at the end of each day, or more frequently as necessary (ex: wet weather). Remove sediment from roads by shoveling, sweeping, or pick up and transport the sediment to a controlled sediment disposal area. ❑ Conduct street washing only after sediment is removed in accordance with the above bullet. ❑ Control street wash wastewater by pumping back on site or otherwise preventing it from discharging into systems tributary to waters of the State. Additional Guidance for Element 2 Minimize construction site access points along linear projects, such as roadways. Street washing may require local jurisdiction approval. Suggested BMPs for Element 2: • BMP C105: Stabilized Construction Access • BMP C106: Wheel Wash • BMP C107: Construction Road / Parking Area Stabilization How did you comply with this section? Construction access will be limited to the existing driveway off of Bay PI. ELEMENT 3: Control Flow Rates ❑ Protect properties and waterways downstream of development sites from erosion and the associated discharge of turbid waters due to increases in the velocity and peak volumetric flow rate of stormwater runoff from the project site. ❑ Where necessary to comply with the bullet above, construct stormwater retention or detention facilities as one of the first steps in grading. Assure that detention facilities function properly before constructing site improvement (e.g. impervious surfaces). ❑ If permanent infiltration ponds are used for flow control during construction, protect these facilities from siltation during the construction phase. Version Date: August 30, 2022 Additional Guidance for Element 3 • Conduct a downstream analysis if changes in flows could impair or alter conveyance systems, streambanks, bed sediment, or aquatic habitat. See III-3.2 Preparing a Stormwater Site Plan for off-site analysis guidelines. • Even gently sloped areas need flow controls such as BMP C235: Wattles or other energy dissipation / filtration structures. Place dissipation facilities closer together on steeper slopes. These methods prevent water from building higher velocities as it flows downstream within the construction site. • Control structures designed for permanent detention BMPs are not appropriate for use during construction without modification. If used during construction, modify the control structure to allow for long-term storage of runoff and enable sediment to settle. Verify that the BMP is sized appropriately for this purpose. Restore BMPs to their original design dimensions, remove sediment, and install a final control structure at completion of the project. • Erosion has the potential to occur because of increases in the volume, velocity, and peak flow rate of stormwater runoff from the project site. The local permitting agency may require infiltration or detention BMP designs that provide additional or different stormwater flow control than the designs detailed in this manual. These requirements may be necessary to address local conditions or to protect properties and waterways downstream. • Velocity of water leaving the site should not exceed 3 feet/second, if the discharge is to a stream or ditch. Install velocity dissipation, such as BMP C207: Check Dams or BMP C202: Riprap Channel Lining to ensure reduction of the flow velocity to a non-erosive level. • If the discharge from a project site is to a municipal storm drainage system, the allowable discharge rate may be limited by the capacity of the public system. It may be necessary to clean the municipal storm drainage system prior to the start of the discharge to prevent scouring solids from the drainage system. Obtain permission from the owner of the collection system before discharging to it. Ensure that no downstream pipes are surcharged as a result of increased flows from the project site. If the discharge from a project site is directly to a flow control exempt receiving water listed in Appendix I-A: Flow Control Exempt Receiving Waters or to an infiltration system, there is no discharge flow limit. Suggested BMPs for Element 3 BMP C203: Water Bars BMP C207: Check Dams • BMP C209: Outlet Protection • BMP C235: Wattles BMP C240: Sediment Trap BMP C241: Sediment Pond (Temporary) • See also V-12 Detention BMPs How did you comply with this section? A silt fence BMP C233 is to be installed along the water front south boundary and up each side of the lot. Version Date: August 30, 2022 ELEMENT 4: Install Sediment Controls ❑ Design, install, and maintain effective erosion controls and sediment controls to minimize the discharge of pollutants. ❑ Construct sediment control BMPs (sediment ponds, traps, filters, etc.) as one of the first steps in grading. These BMPs shall be functional before other land disturbing activities take place. ❑ Minimize sediment discharges from the site. The design, installation and maintenance of erosion and sediment controls must address factors such as the amount, frequency, intensity and duration of precipitation, the nature of resulting stormwater runoff, and soil characteristics, including the range of soil particle sizes expected to be present on the site. ❑ Direct stormwater runoff from disturbed areas through a sediment pond or other appropriate sediment removal BMP, before the runoff leaves a construction site or before discharge to an infiltration facility. Runoff from fully stabilized areas may be discharged without a sediment removal BMP, but must meet the flow control performance standard in Element#3, bullet#1. ❑ Locate BMPs intended to trap sediment on-site in a manner to avoid interference with the movement of juvenile salmonids attempting to enter off-channel areas or drainages. ❑ Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to increase sediment removal, and maximize stormwater infiltration. ❑ Where feasible, design outlet structures that withdraw impounded stormwater from the surface to avoid discharging sediment that is still suspended lower in the water column. Additional Guidance for Element 4 • Outlet structures that withdraw impounded stormwater from the surface to avoid discharging sediment that is still suspended lower in the water column are for the construction period only. If installing a floating pump structure, include a stopper to prevent the pump basket from hitting the bottom of the pond. • If a sediment trapping BMP utilizes a control structure that will also be used in a permanent detention BMP application, the control structure construction must be finalized for the permanent BMP application upon project completion. • Install sediment controls in a manner that protects the sensitive areas and their buffers marked in accordance with Element 1: Preserve Vegetation / Mark Clearing Limits. • Where feasible, direct stormwater to vegetated areas to increase sediment removal and maximize stormwater infiltration. • Seed and mulch earthen structures such as dams, dikes, and diversions according to the timing indicated in Element 5: Stabilize Soils. • Full stabilization includes concrete or asphalt paving; quarry spalls used as ditch lining; or the use of rolled erosion products, a bonded fiber matrix product, or vegetative cover in a manner that will fully prevent soil erosion. • The Local Permitting Authority may inspect and approve areas fully stabilized by means other than pavement or quarry spalls. Version Date: August 30, 2022 Suggested BMPs for Element 4: BMP C231: Brush Barrier • BMP C232: Gravel Filter Berm • BMP C233: Silt Fence • BMP C234: Vegetated Stri p • BMP C235: Wattles • BMP C240: Sediment Trap • BMP C241: Sediment Pond (Temporary • BMP C250: Construction Stormwater Chemical Treatment • BMP C251: Construction Stormwater Filtration How did you comply with this section? Per BMP C233 a silt fence will be installed as noted in element 3. To be installed prior to the start of construction. BMP to be monitored daily and repaired as needed. ELEMENT 5: Stabilize Soils ❑ Stabilize exposed and unworked soils by application of effective BMPs that prevent erosion. Applicable BMPs include, but are not limited to: temporary and permanent seeding, sodding, mulching, plastic covering, erosion control fabrics and matting, soil application of polyacrylamide (PAM), the early application of gravel base early on areas to be paved, and dust control. ❑ Control stormwater volume and velocity within the site to minimize soil erosion. ❑ Control stormwater discharges, including both peak flow rates and total stormwater volume, to minimize erosion at outlets and to minimize downstream channel and stream bank erosion. ❑ Soils must not remain exposed and unworked for more than the time periods set forth below to prevent erosion. o During the dry season (May 1 — Sept 30): 7 days o During the wet season (Oct 1 —Apr 30): 2 days ❑ Stabilize soils at the end of the shift before a holiday or weekend if needed based on the weather forecast. ❑ Stabilize soil stockpiles from erosion, protect with sediment trapping measures, and where possible, be located away from storm drain inlets, waterways, and drainage channels. ❑ Minimize the amount of soil exposed during construction activity. ❑ Minimize the disturbance of steep slopes. ❑ Minimize soil compaction and, unless infeasible, preserve topsoil. Version Date: August 30, 2022 Additional Guidance for Element 5 • Soil stabilization BMPs should be appropriate for the time of year, site conditions, estimated duration of use, and potential water quality impacts that stabilization agents may have on downstream waters or ground water. • Ensure that gravel base used for stabilization is clean and does not contain fines or sediment. Suggested BMPs for Element 5: • BMP C120: Temporary and Permanent Seeding • BMP C121: Mulching • BMP C122: Nets and Blankets • BMP C123: Plastic Covering • BMP C124: Sodding • BMP C125: Topsoiling /Composting • BMP C126: Polyacrylamide (PAM)for Soil Erosion Protection • BMP C130: Surface Roughening • BMP C131: Gradient Terraces • BMP C140: Dust Control How did you comply with this section? Install plastic covering per BMP C123 on Soils Stockpiles. BMP to be monitored daily and repaired as needed. ELEMENT 6: Protect Slopes ❑ Design and construct cut-and-fill slopes in a manner to minimize erosion. Applicable practices include, but are not limited to, reducing continuous length of slope with terracing and diversions, reducing slope steepness, and roughening slope surfaces (Ex: track walking). ❑ Divert off-site stormwater (run-on) or ground water away from slopes and disturbed areas with interceptor dikes, pipes, and/or swales. Off-site stormwater should be managed separately from stormwater generated on the site. ❑ At the top of slopes, collect drainage in pipe slope drains or protected channels to prevent erosion. Temporary pipe slope drains must be sized to convey the flow rate calculated by the one fo the following methods: • Single Event Hydrograph Method: The peak volumetric flow rate calculated using a 10-minute time step from a Type 1 A, 10-year, 24-hour frequency storm, or; • Continuous Simulation Method: The 10-year peak flow rate, as determined by an approved continuous runoff model with a 15-minute time step. The hydrologic analysis must use the existing land cover condition for predicting flow rates from tributary areas outside the project limits. For tributary areas on the project site, the analysis must use the temporary or permanent project land cover condition, whichever will produce the highest flow rates. Version Date: August 30, 2022 If using the Western Washington Hydrology Model (WWHM) to predict flows, bare soil areas should be modeled as "landscaped" area. ❑ Place excavated material on the uphill side of trenches, consistent with safety and space considerations. ❑ Place check dams at regular intervals within constructed channels that are cut down a slope. Additional Guidance for Element 6 • Consider soil type and its potential for erosion. • Stabilize soils on slopes, as specified in Element 5: Stabilize Soils. • BMP combinations are the most effective method of protecting slopes with disturbed soils. For example, use both BMP C121: Mulching and BMP C122: Nets and Blankets in combination. Suggested BMPs for Element 6: • BMP C120: Temporary and Permanent Seeding • BMP C121: Mulching • BMP C122: Nets and Blankets • BMP C123: Plastic Covering • BMP C124: Sodding • BMP C130: Surface Roughening • BMP C131: Gradient Terraces • BMP C200: Interceptor Dike and Swale • BMP C201: Grass-Lined Channels BMP C203: Water Bars BMP C204: Pipe Slope Drains BMP C205: Subsurface Drains BMP C206: Level Spreader • BMP C207: Check Dams BMP C208: Triangular Silt Dike (TSD) How did you comply with this section? The site is flat with a 1% to 2% slope and slope protection will not be an issue. Version Date: August 30, 2022 ELEMENT 7: Protect Drain Inlets ❑ Protect all storm drain inlets made operable during construction so that stormwater runoff does not enter the conveyance system without first being filtered or treated to remove sediment. ❑ Clean or remove and replace inlet protection devices when sediment has filled one-third of the available storage (unless a different standard is specified by the product manufacturer). Additional Guidance for Element 7 • Protect all existing storm drain inlets so that stormwater runoff does not enter the conveyance system without first being filtered or treated to remove sediment. • Keep all approach roads clean. Do not allow sediment and street wash water to enter storm drains without prior and adequate treatment (as defined above) unless treatment is provided before the storm drain discharges to waters of the State. • Inlets should be inspected weekly at a minimum and daily during storm events. Suggested BMPs for Element 7 • BMP C220: Inlet Protection How did you comply with this section? Storm Drain Inlet protection devices will be installed at existing catch basins in the immediate vicinity of the project. To be installed prior to the start of any construction. Nearest CB is must north of the site approximately 260 feet on Bay Place. BMP to he monitored daily and repaired as needed_ ELEMENT 8: Stabilize Channels and Outlets ❑ Design, construct, and stabilize all on-site conveyance channels to prevent erosion from the flow rate calcultated by one the following methods: o Single Event Hydrograph Method: The peak volumetric flow rate calculated using a 10-minute time step from a Type 1 A, 10-year, 24-hour frequency storm, or; o Continuous Simulation Method: The 10-year peak flow rate, as determined by an approved continuous runoff model with a 15-minute time step. The hydrologic analysis must use the existing land cover condition for predicting flow rates from tributary areas outside the project limits. For tributary areas on the project site, the analysis must use the temporary or permanent project land cover condition, whichever will produce the highest flow rates. If using the Western Washington Hydrology Model (WWHM) to predict flows, bare soil areas should be modeled as "landscaped" area. ❑ Provide stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent streambanks, slopes, and downstream reaches at the outlets of all conveyance systems. Additional Guidance for Element 8 The best method for stabilizing channels is to completely line the channel with BMP C122: Nets and Blankets first, then add BMP C207: Check Dams as necessary to function as an anchor and to slow the flow of water. Version Date: August 30, 2022 Suggested BMPs for Element 8 BMP C122: Nets and Blankets • BMP C202: Riprap Channel Lining • BMP C207: Check Dams • BMP C209: Outlet Protection How did you comply with this section? No stormwater runoff will be conveyed off site via channels, swales, or streams. ELEMENT 9: Control Pollutants Design, install, implement and maintain effective pollution prevention measures to minimize the discharge of pollutants. The project proponent must: ❑ Handle and dispose of all pollutants, including waste materials and demolition debris that occur on site in a manner that does not cause contamination of stormwater. ❑ Provide cover, containment, and protection from vandalism for all chemicals, liquid products, petroleum products, and other materials that have the potential to pose a threat to human health or the environment. On-site fueling tanks must include secondary containment. Secondary containment means placing tanks or containers within an impervious structure capable of containing 110% of the volume contained in the largest tank within the containment structure. Double-walled tanks do not require additional secondary containment. ❑ Conduct maintenance, fueling, and repair of heavy equipment and vehicles using spill prevention and control measures. Clean contaminated surfaces immediately following any spill incident. ❑ Discharge wheel wash or tire bath wastewater to a separate on-site treatment system that prevents discharge to surface water, or to the sanitary sewer, with local sewer district approval. ❑ Apply fertilizers and pesticides in a manner and at application rates that will not result in loss of chemical to stormwater runoff. Follow manufacturers' label requirements for application rates and procedures. ❑ Use BMPs to prevent contamination of stormwater runoff by pH-modifying sources. The sources for this contamination include, but are not limited to: recycled concrete stockpiles, bulk cement, cement kiln dust, fly ash, new concrete washing and curing waters, waste streams generated from concrete grinding and sawing, exposed aggregate processes, dewatering concrete vaults, concrete pumping and mixer washout waters. ❑ Adjust the pH of stormwater if necessary to prevent violations of water quality standards. ❑ Assure that washout of concrete trucks is performed off site or in designated concrete washout areas only. Do not wash out concrete truck drums or concrete handling equipment onto the ground, or into storm drains, open ditches, streets, or streams. Washout of small concrete handling equipment may be Version Date: August 30, 2022 disposed of in a formed area awaiting concrete where it will not contaminate surface or ground water. Do not dump excess concrete on site, except in designated concrete washout areas. Concrete spillage or concrete discharge directly to ground water or surface waters of the State is prohibited. Do not wash out to formed areas awaiting infiltration BMPs. ❑ Obtain written approval from Ecology before using chemical treatment other than CO2, dry ice, or food grade vinegar to adjust pH. ❑ Uncontaminated water from water-only based shaft drilling for construction of building, road, and bridge foundations may be infiltrated provided the wastewater is managed in a way that prohibits discharge to surface waters. Prior to infiltration, water from water-only based shaft drilling that comes into contact with curing concrete must be neutralized until pH is in the range of 6.5 to 8.5 (su). Additional Guidance for Element 9 • Wheel wash and/or tire bath wastewater can be combined with wastewater from concrete washout areas if the wastewaters will be properly disposed of at an offsite location or treatment facility. • Do not use upland land applications for discharging wastewater from concrete washout areas. • Woody debris may be chopped and spread on site. • Conduct oil changes, hydraulic system drain down, solvent and degreasing cleaning operations, fuel tank drain down and removal, and other activities which may result in discharge or spillage of pollutants to the ground or into stormwater runoff using spill prevention measures, such as drip pans. • Clean contaminated surfaces immediately following any discharge or spill incident. Emergency repairs may be performed on-site using temporary plastic placed beneath and, if raining, over the vehicle. Suggested BMPs for Element 9 • BMP C151: Concrete Handlinq BMP C152: Sawcutting and Surfacing Pollution Prevention BMP C153: Material Delivery, Storage, and Containment BMP C154: Concrete Washout Area BMP C250: Construction Stormwater Chemical Treatment • BMP C251: Construction Stormwater Filtration • BMP C252: Treating and Disposing of pH Water Also see the Source Control BMPs detailed in Volume IV How did you comply with this section? Per BMP C154 a Concrete Washout Area is to be installed onsite to capture contaminated water from concrete washouts. To be installed prior to concrete installation. BMP to be monitored daily and repaired as needed. Contractor is to provide spill prevention kits for excavation and concrete crews are required on Site. Version Date: August 30, 2022 ELEMENT 10: Control De-Watering ❑ Discharge foundation, vault, and trench dewatering water, which have characteristics similar to stormwater runoff at the site, into a controlled conveyance system before discharge to BMP C240: Sediment Trap or BMP C241: Sediment Pond (Temporary. ❑ Discharge foundation, vault, and trench dewatering water, which have similar characteristics to stormwater runoff at the site, into a controlled conveyance system before discharge to Discharge clean, non-turbid dewatering water, such as well-point ground water, to systems tributary to, or directly into surface waters of the State, as specified in Element 8: Stabilize Channels and Outlets, provided the dewatering flow does not cause erosion or flooding of receiving waters. Do not route clean dewatering water through stormwater sediment BMPs. Note that"surface waters of the State" may exist on a construction site as well as off site; for example, a creek running through a site.Handle highly turbid or contaminated dewatering water separately from stormwater. ❑ Handle highly turbid or otherwise contaminated dewatering separately from stormwater. ❑ Other dewatering treatment or disposal options may include: 1. Infiltration 2. Transport off-site in a vehicle, such as a vacuum flush truck, for legal disposal in a manner that does not pollute state waters. 3. Ecology-approved on-site chemical treatment or other suitable treatment technologies. 4. Sanitary or combined sewer discharge with local sewer district approval, if there is no other option. 5. Use of a sedimentation bag with outfall to a ditch or swale for small volumes of localized dewatering. Additional Guidance for Element 10 • Channels must be stabilized, as specified in Element 8: Stabilize Channels and Outlets. • Construction equipment operation, clamshell digging, concrete tremie pour, or work inside a cofferdam can create highly turbid or contaminated dewatering water. Discharging sediment-laden (muddy) water into waters of the State likely constitutes violation of water quality standards for turbidity. The easiest way to avoid discharging muddy water is through infiltration and preserving vegetation. • Dewatering water from contaminated sites must be handled separately from stormwater. Direct contaminated stormwater to a sanitary sewer where allowed by the local sewer authority, or to other approved treatment. Suggested BMPs for Element 10 • BMP C203: Water Bars • BMP C236: Vegetative Filtration How did you comply with this section? If dewatering is needed all discharge will be directed to a temporary sediment trap BMP C240 prior to discharge to the city storm drainage system. Version Date: August 30, 2022 ELEMENT 11: Maintain BMPs ❑ Maintain and repair all temporary and permanent erosion and sediment control BMPs as needed to assure continued performance of their intended function in accordance with BMP specifications. ❑ Remove all temporary erosion and sediment control BMPs within 30 days after achieving final site stabilization or after the temporary BMPs are no longer needed. Additional Guidance for Element 11 • Some temporary erosion and sediment control BMPs are biodegradable and designed to remain in place following construction. BMP C122: Nets and Blankets is an example of a BMP with biodegradable options. • Provide protection to all BMPs installed for the permanent control of stormwater from sediment and compaction. All BMPs that are to remain in place following completion of construction shall be examined and placed in full operating conditions. If sediment enters the BMPs during construction, it shall be removed and the facility shall be returned to the conditions specified in the construction documents. • Remove or stabilize trapped sediment on site. Permanently stabilize disturbed soil resulting from removal of BMPs or vegetation. Suggested BMPs for Element 11 • BMP C150: Materials on Hand • BMP C160: Certified Erosion and Sediment Control Lead How did you comply with this section? BMPs to be monitored daily and repaired as needed and/or as required by the City of Anacortes. ELEMENT 12: Manage the Project ❑ Phase development projects to the maximum degree practicable and take into account seasonal work limitations. ❑ Inspect, maintain and repair all BMPs as needed to assure continued performance of their intended function. Projects regulated under the Construction Stormwater General Permit (CSWGP) must conduct site inspections and monitoring in accordance with Special Condition S4 of the CSWGP. ❑ Maintain, update, and implement the Construction SWPPP. ❑ Projects that disturb one or more acres must have site inspections conducted by a Certified Erosion and Sediment Control Lead (CESCL). Project sites disturbing less than one acre may have a CESCL or a person without CESCL certification conduct inspections. By the initiation of construction, the Construction SWPPP must identify the CESCL or inspector, who must be present on site or on-call at all times. Version Date: August 30, 2022 Additional Guidance for Element 12 The project manager must ensure that the project is built in such a way to comply with all Construction SWPPP Elements, as detailed in this section. Considerations for the project manager include, but are not limited to: • construction phasing • seasonal work limitations • coordination with utilities and other contractors • inspection • monitoring • maintaining an updated construction SWPPP Phasing of Construction Phase development projects where feasible in order to prevent soil erosion and transporting of sediment from the site during construction. Revegetate exposed areas and maintain that vegetation as an integral part of the clearing activities for any phase. Clearing and grading activities for developments shall be permitted only if conducted using an approved site development plan (e.g., subdivision approval) that establishes permitted areas of clearing, grading, cutting, and filling. Minimize removing trees and disturbing or compacting native soils when establishing permitted clearing and grading areas. Show on the site plans and the development site permitted clearing and grading areas and any other areas required to preserve critical or sensitive areas, buffers, native growth protection easements, or tree retention areas as may be required by local jurisdictions. Inspection All BMPs must be inspected, maintained, and repaired as needed to assure continued performance of their intended function. Site inspections must be conducted by a person knowledgeable in the principles and practices of erosion and sediment control. The person must have the skills to 1) assess the site conditions and construction activities that could impact the quality of stormwater, and 2) assess the effectiveness of erosion and sediment control measures used to control the quality of stormwater discharges. For construction sites one acre or larger that discharge stormwater to surface waters of the state, a CESCL must be identified in the construction SWPPP; this person must be on-site or on-call at all times. Certification must be obtained through an approved training program that meets the erosion and sediment control training standards established by Ecology. See BMP C160: Certified Erosion and Sediment Control Lead. Appropriate BMPs or design changes shall be implemented as soon as possible whenever inspection and/or monitoring reveals that the BMPs identified in the Construction SWPPP are inadequate, due to the actual discharge of/or potential to discharge a significant amount of any pollutant. The CESCL or inspector must examine stormwater visually for the presence of suspended sediment, turbidity, discoloration, and oil sheen. They must evaluate the effectiveness of BMPs and determine if it is necessary to install, maintain, or repair BMPs to improve the quality of stormwater discharges. Based on the results of the inspection, construction site operators must correct the problems identified by: • Reviewing the Construction SWPPP for compliance with the 13 elements and making appropriate revisions within 7 days of the inspection. • Immediately beginning the process of fully implementing and maintaining appropriate source control and/or treatment BMPs as soon as possible, addressing the problems no later than within 10 days of the inspection. If installation of necessary treatment BMPs is not feasible within 10 days, the construction site operator may request an extension within the initial 10-day response period. • Documenting BMP implementation and maintenance in the site log book (applies only to sites that have coverage under the Construction Stormwater General Permit). Version Date: August 30, 2022 The CESCL or inspector must inspect all areas disturbed by construction activities, all BMPs, and all stormwater discharge points at least once every calendar week and within 24 hours of any discharge from the site. (For purposes of this condition, individual discharge events that last more than one day do not require daily inspections. For example, if a stormwater pond discharges continuously over the course of a week, only one inspection is required that week.) The CESCL or inspector may reduce the inspection frequency for temporary stabilized, inactive sites to once every calendar month Maintaining an Updated Construction SWPPP Retain the Construction SWPPP on-site or within reasonable access to the site. Modify the Construction SWPPP 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 Construction SWPPP must be modified if, during inspections or investigations conducted by the owner/operator, or the applicable local or state regulatory authority, it is determined that the Construction SWPPP is ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site. Modify the Construction SWPPP as necessary to include additional or modified BMPs designed to correct problems identified. Complete revisions to the Construction SWPPP within seven (7) days following the inspection. Suggested BMPs for Element 12 • BMP C150: Materials on Hand • BMP C160: Certified Erosion and Sediment Control Lead • BMP C162: Scheduling How did you comply with this section? BMP to be monitored daily and repaired as needed and the responsibility of the owner. Project does not require a certified CESCL. ELEMENT 13: Protect Low Impact Development BMPS The primary purpose of On-Site Stormwater Management is to reduce the disruption of the natural site hydrology through infiltration. BMPs used to meet 1-3.4.5 MR5: On-Site Stormwater Management (often called LID BMPs) are permanent facilities. ❑ Protect all LID BMPs (including, but not limited to BMP T7.30: Bioretention, BMP T5.14: Rain Gardens, and BMP T5.15: Permeable Pavements) from sedimentation through installation and maintenance of erosion and sediment control BMPs on portions of the site that drain into the LID BMPs. Restore the BMPs to their fully functioning condition if they accumulate sediment during construction. Restoring the BMP must include removal of sediment and any sediment-laden Bioretention/Rain Garden soils, and replacing the removed soils with soils meeting the design specification. ❑ Maintain the infiltration capabilities of LID BMPs by protecting against compaction by construction equipment and foot traffic. Protect completed lawn and landscaped areas from compaction due to construction equipment. ❑ Control erosion and avoid introducing sediment from surrounding land uses onto BMP T5.15: Permeable Pavements. Do not allow muddy construction equipment on the base material or pavement. Do not allow sediment-laden runoff onto permeable pavements or base materials. Version Date: August 30, 2022 ❑ Permeable pavement fouled with sediments or no longer passing an initial infiltration test must be cleaned using procedures in accordance with this manual or the manufacturer's procedures. ❑ Keep all heavy equipment off existing soils under LID BMPs that have been excavated to final grade to retain the infiltration rate of the soils. Additional Guidance for Element 13 See Chapter 5: Precision Site Preparation, Construction & Inspection of LID Facilities in the LID Technical Guidance Manual for Puget Sound(Hinman and Wulkan, 2012) for more detail on protecting LID integrated management practices. Note that the LID Technical Guidance Manual for Puget Sound(Hinman and Wulkan, 2012) is for additional informational purposes only. You must follow the guidance within this manual if there are any discrepancies between this manual and the LID Technical Guidance Manual for Puget Sound(Hinman and Wulkan, 2012). Suggested BMPs for Element 13 • BMP C102: Buffer Zones • BMP C103: High-Visibility Fence • BMP C200: Interceptor Dike and Swale • BMP C201: Grass-Lined Channels • BMP C207: Check Dams • BMP C208: Triangular Silt Dike (TSD) • BMP C231: Brush Barrier • BMP C233: Silt Fence • BMP C234: Vegetated Stri p How did you comply with this section? No LID BMPS are proposed. Aaron Parrish Applicant Signature Date Version Date: August 30, 2022 TAB 5 (MINIMUM REQUIREMENT#5) 1-3.4.5 Minimum Requirement#5 —On-site Stormwater Management Projects shall employ Stormwater Management BMPs in accordance with the following thresholds, standards, and lists to infiltrate, disperse, and retain stormwater runoff on site to the extent feasible without causing flooding or erosion impacts. Project thresholds that trigger Minimum Requirements #1 through #5, shall utilize the On-site Stormwater Management BMP's from List#1 for all surfaces within each type of surface in List#1; or, Demonstrate compliance with the LID Performance Standard. Projects selecting this option cannot use Rain Gardens. They may choose to use Bioretention BMP's as described in Chapter V-7 — Infiltration and Bioretention Treatment Facilities to achieve the LID Performance Standard. Refer to this section of the reference Manual for all Feasibility or Infeasibility Criteria for List#1 and List#2. Is this project Flow Control Exempt? yes (Yes\No) (See Appendix I-E: Flow Control-Exempt Surface Water). If yes, provide reasoning from the applicability section of 1-2.5.7 Minimum Requirement#7: Flow Control). If No, then the project triggers Minimum Requirement#7 (1-2.5.7) and possibly Minimum Requirement#8 (1-2.5.8). The flow has a direct discharge to Flounder Bay a Flow Control Exempt body of water. If the project is Flow Control Exempt, select from the List 3 below: (Skip List 1 and List 2) o BMP T5.13 Post Construction Soils Quality and Depth o BMP T5.10A: Downspout Full Infiltration, or; o BMP T5.10B Downspout Dispersion Systems, or; o BMP T5.10C: Performated Stub-out Connections, or; LID Performance Standard The LID Performance Standard compliance method for Minimum Requirement#5 requires modeling the proposed Flow Control BMPs to demonstrate the flow reduction as described below. Note that in order to meet the LID Performance Standard, the chosen Flow Control BMPs will most likely need to include infiltration. Stormwater discharges shall match developed discharge durations to pre-developed durations for the range of pre-developed discharge rates from 8% of the 2-year peak flow to 50% of the 2-year peak flow. Refer to the Flow Control Performance Standard section in 1-3.4.7 MR7: Flow Control for information about the assignment of the pre-developed condition. Project sites that must also meet 1-3.4.7 MR7: Flow Control must match flow durations between 8% of the 2-year flow through the full 50-year flow. Designers selecting this option cannot use BMP T5.14: Rain Gardens to achieve the LID Performance Standard. They may choose to use BMP T7.30: Bioretention to achieve the LID Performance Standard. Version Date: August 30, 2022 The List Approach The List Approach compliance method for Minimum Requirement#5 requires evaluating the BMPs in Table 1-3.2: The List Approach for MR5 Compliance. For each surface, evaluate the feasibility of the BMPs in the order listed, and use the first BMP that is considered feasible. The designer must document the site conditions and infeasibility criteria used to deem BMPs infeasible. Once a BMP is deemed feasible and used for a surface, no other BMP from the list is necessary for that surface. If all BMPs in the list are infeasible, then the designer must document the site conditions and infeasibility criteria used to deem each BMP infeasible. This documentation will demonstrate compliance with Minimum Requirement#5. Feasibility shall be determined by evaluation against: • Design criteria, limitations, and infeasibility criteria identified for each BMP in this manual; and • Competing Needs Criteria as listed below. All sites are required to utilize BMP T5.13 — Post Construction Soil Quality and Depth. For each surface, consider the BMP's in the order listed for that type of surface. Use the first BMP that is considered feasible. No other on-site Stormwater Management BMP is necessary for that surface. Feasiblity shall be determined by evaluation against: 1. Design criteria, limitations and infeasiblity criteria identified for each BMP in this manual, and; 2. Competing needs criteria listed in Chapter V-5 — On-site Stormwater Management. Lawn and Landscaped Area: • BMP T5.13: Post-Construction Soil Quality and Depth. (Attach Detail in Report) Refer to this site for requirements and specifications. All projects are required to utilize this BMP. http://www.soilsforsalmon.orq/pdf/Soil BMP Manual.pdf See Appendix 3 for the "Model Soil Management Plan for BMP T5.13" to be submitted with Drainage Report and Application Material. An alternate document acceptable to the City of Anacortes is a Test Report provided by the Soils Supplier that identifies the soils to be used meet the specifications outlined under Minimum Requirement 5. The specifications are in both WSDOT and CSI Formats. For specifications, refer to the above referenced PDF. This submittal can be a deferred submittal since most projects are not sure who the supplier will be at the time of building permit application. For projects that trigger Minimum Requirements 1 through 5, the Test Report will be provided to the Building Department. Projects triggering Minimum Requirements 1 through 9, the Test Report will be provided to the Engineering Department. Version Date: August 30, 2022 APPENDIX 1 -Survey performed by a Professional Land Surveyor The object of this appendix is to ensure that the property has a minimum of 3 out of 5 property corners visible to ensure that the structures are placed within the required setbacks. SKYLINE NO, 7 SECTIONS 2,7 81 28 o TWP. 35 N.,, R, I E., W.M. CITY OF ANACORTES SKAGIT COUNTY,,,, WASHINGTON sv Aff-W, *77, —1�Z �x 'R g, jk' ........... r'U 14 low", 24 f Z'r W r We J Vd?")11? rp eg 90 eo J6'e"'i "A" ot SCALE P*10 3� P"Ivj 1'j a -A, MAP, Jym 'Fe: 0 J�'41 tl Al A0 It, SHEET 2 OF 2 SHEETS ............... 9-71 Version Date: August 30, 2022 APPENDIX 3 — Model Soll Management Plan for BMP T5.13 An alternate document acceptable to the City of Anacortes is a Test Report provided by the Soils Supplier that identifies the soils to be used meet the specifications outlined under Minimum Requirement 5. The specifications are in both WSDOT and CSI Formats. For specifications, refer to the above referenced PDF. This submittal can be a deferred submittal since most projects are not sure who the supplier will be at the time of building permit application. For projects that trigger Minimum Requirements 1 through 5, the Test Report will be provided to the Building Department. Projects triggering Minimum Requirements 1 through 9, the Test Report will be provided to the Engineering Department. Version Date: August 30, 2022 DEFERRED SUBMITTAL: PROVIDE A TEST REPORT FROM SOILS SUPPLIER TO THE BUILDING DEPT. PROJECT INFORMATION "Model Soil Management Plan for BMP T5.13" age# of pages Complete all information on page 1; only site address and permit number on additional pages. Site Address/Lot No.: Permit Type: Permit Number: Permit Holder: Phone: Mailing Address: Contact Person: Phone: Plan Prepared By: ATTACHMENTS REQUIRED (Check off required items that are attached to this plan) Site Plan showing,to scale: Areas of undisturbed native vegetation(no amendment required) New planting beds and turf areas(amendment required) Type of soil improvement proposed for each area Soil test results(required if proposing custom amendment rates Product test results for proposed amendments AREA# (should match Area#on Site Plan) PLANTING TYPE Turf Undisturbed native vegetation Planting Beds Other: SQUARE FOOTAGE OF THIS AREA: square feet SCARIFICATION inches(depth)of scarification needed to achieve finished total 12"loosened depth. Subsoil will be scarified PRE-APPROVED inches of compost or imported topsoil applied AMENDMENT METHOD: X 3.1 (conversion factor, inches to cubic yards) PRODUCT: Topsoil import =cu.yards per 1,000 sq. ft. Amend with compost X ,000s sq.ft. in this area Stockpile and amend =cubic yards of amendment QUANTITY: CU.YDS. cu.yds. stockpiled) needed to cover this area to designated depth) CUSTOM AMENDMENT Attach test results and calculations. Topsoil import inches organic matter or topsoil import PRODUCT: Topsoil&compost lift X 3.1 Amend =cu.yards/ 1,000 sq. ft. Stockpile and amend X ,000s sq.ft. in this area ( cu.yds. stockpiled) =cubic yards of amendment QUANTITY: CU.YDS. MULCH ,000 sq.ft. PRODUCT: X 6.2 (conversion, to give 2 inch mulch depth) =cubic yards of mulch QUANTITY: CU.YDS. TOTAL AMENDMENT/TOPSOIL/MULCH FOR ALL AREAS (complete on page 1 only, totaling all areas/ a es in this Plan ❑ Product#1: ❑ Quantity: cu.yds. ❑ Test Results: % organic matter C:N ratio<25:1 (except mulch,or<35:1 for native plants) "stable" es/no ❑ Product#2: ❑ Quantity: cu.yds. ❑ Test Results: % organic matter C:N ratio<25:1 exce t mulch,or<35:1 for native plants) "stable" es/no ❑ Product#3: ❑ Quantity: cu.yds. ❑ Test Results: % organic matter C:N ratio<25:1 (except mulch,or<35:1 for nativeplants) "stable" es/no Date: Inspector: Approved: Revisions Required: Date: Inspector: Approved: Revisions Required: Version Date: August 30, 2022 APPENDIX 4— DetermInIng Construct'lon S'Ite Sediment Damage Potent'lal (AppendIx 7 — NPDES Phase 11 Perm'1t) Note: See attached. All projects within the City of Anacortes are required to complete that document under Appendix 4. Version Date: August 30, 2022 Western Washington Phase II Stormwater Permit L APPENDIX 7 - Determining Construction Site Sediment Damage Potential The following rating system allows objective evaluation of a particular development site's potential to discharge sediment. Permittees may use the rating system below or develop alternative process designed to identify site-specific features which indicate that the site must be inspected prior to clearing and construction. Any alternative evaluation process must be documented and provide for equivalent environmental review. Step one is to determine if there is a sediment/erosion sensitive feature downstream of the development site. If there is such a site downstream complete step two, assessment of hydraulic nearness. If there is a sediment/erosion sensitive feature and it is hydraulically near the site then go to step three to determine the construction site sediment transport potential. H. STEP 1 —Sediment/Erosion Sensitive Feature Identification Sediment/erosion sensitive features are areas subject to significant degradation due to the effect of sediment deposition or erosion. Special protection must be provided to protect them. Sediment/erosion sensitive features include but are not limited to: L Salmonid bearing fresh water streams and their tributaries or freshwater streams that would be Salmonid bearing if not for anthropogenic barriers; 11. Lakes; 111. Category I, II, and III wetlands; iv. Marine near-shore habitat; V. Sites containing contaminated soils where erosion could cause dispersal of contaminants; and vi. Steep slopes (25% or greater) associated with one of the above features. Identify any sediment/erosion sensitive features, and proceed to step two. If there are none the assessment is complete. 111. STEP 2 — Hydraulic Nearness Assessment Sites are hydraulically near a feature if the pollutant load and peak quantity of runoff from the site will not be naturally attenuated before entering the feature. The conditions that render a site hydraulically near to a feature include, but are not limited to, the following: i. The feature or a buffer to protect the feature is within 200 feet downstream of the site. ii. Runoff from the site is tight-lined to the feature or flows to the feature through a channel or ditch. t. l.i r l, 2013, l , ,. II,�my, l ! 1) ii ii� i� ii f 1�,m, I m "r i , u I zJ°o Ill",I i iia;tl Ill,,nV, g Version Date: August 30, 2022 A site is not hydraulically near a feature if one of the following takes place to provide attenuation before runoff from the site enters the feature: iv. Sheet flow through a vegetated area with dense ground cover V. Flow through a wetland not included as a sensitive feature vi. Flow through a significant shallow or adverse slope, not in a conveyance channel, between the site and the sensitive feature. Identify any of the sediment/erosion sensitive features from step one that are hydraulically near the site, and proceed to step three. If none of the sediment/erosion sensitive features are hydraulically near the site, the assessment is complete. vii. STEP 3— Construction Site Sediment Transaort Potential Using the worksheet below, determine the total points for each development site. Assign points based on the most critical condition that affects 10% or more of the site. If soil testing has been performed on site, the results should be used to determine the predominant soil type on the site. Otherwise, soil information should be obtained from the county soil survey to determine Hydrologic Soil Group (Table of Engineering Index Properties for step 1.D) and Erosion Potential (Table of Water Features for step 1.E) When using the county soil survey, the dominant soil type may be in question, particularly when the site falls on a boundary between two soil types or when one of two soil types may be present on a site. In this case, the soil type resulting in the most points on the rating system will be assumed unless site soil tests indicate that another soil type dominates the site. Use the point score from Step 3 to determine whether the development site has a high potential for sediment transport off of the site. Total Score Transport Rating <100 Low 11100 High A high transport rating indicates a higher risk that the site will generate sediment contaminated runoff. Construction Site Sediment Transport Potentia|Worksheet A. Points 2% orless -0 >2-5% ----------........-------------_..5 >5-10% ------------.''''.------------. 15 >10-15% ------------........----------30 >15% -----------.......------------_..50 B. Site Area to be cleared and/or graded: <5,000 sq. ft ...................................................................................0 5.000 sq. ft. - 1 acre................................................................... >1 acres ..................................................................................... C. Quantity of cut and/or fill on site: <500 cubic yards................................................................................0 500 -5.00O cubic yards ----------------------. 5 >5.000 - 10.000 cubic yards.........................................................10 >10.000 -20.000 cubic yards..................................................... -2 5 >20.000 cubic yards -----------------------40 D. Hydrologic soilgroup A................................................................................ _0 Hydrologic soil group 8.................................................................10 Hydrologic soil group C..............................................................._2 0 Hydrologic soil group [)..............................................................._4O E. GW, GP, SW, SPsoils...................................................................................... _O Dual classifications M. GP-GM, GW-GC, GP-GC, SW-SK SW-SC. SP-SM. |SP-SC)---------10 GM. GC, SM, SC soils..................................................................20 Mi- CL, MH. CH soils------------------_--..4O 1 F. Surface or Groundwater entering site identified and intercepted : Yes.................................................................................................0 No ................................................................................................25 G. Depth of cut or height of fill >1 0 feet: Yes...............................................................................................25 No...........................................................................................................0 IL Yes 50 No...........................................................................................................0 TOTAL POUNTS------------------------------- 10 608f done prior to may 8mt. Either way, it is still low. See full size plan site,APPENDIX 6 Documented Site Photos (Show all directions of the frontage) I( ' V ✓iil I �V I v , �;��vo.,, � f ° r��w�`'�i III Ik w✓ o y IIr� ��rimjrvn✓✓rr�>r�yri +.r 'ii�r�'��✓%�i��l��l�% /� .r �y ..,,,,._�. ;,�;+�, p W 1 I +r '" tV � ilili III ;r ji"��/`���/�/�l%f�I�/��irri/j�,,x�h�✓'r i i /,.�jr,i, / f I ��,,,, I III j�i s ,,,✓1 r.,�r„r✓i✓4�// iil�✓�liui i��ji/�/i���/r�%ii'�� 1 i,llr�»e �.���1, � l�� M VtN ✓�(�. ��(ii,! ai///�///� r/ � I I (.: III E' 1' �i. i r,/� �../r r � ,,,,u.n.. ii// llluG /%.,11✓/i/�,i.,riri iir ,...,.x „,..,, z�! it/i,u�G�--, if/ „,. / .✓/r, /l%/�/ ,, ,,, er � „�.... /%/11// /%/// r ✓� � ,.. : it / i�Iei / av,.. rr�, ,....,.�,�.,.. ✓��i/%%///l„(lll/% ,� i%/i//%/% G ,. ,.;,.,,;.,�„r, gfi, / r ., /�f,i,,:i/r,i Ali/�✓r,,, ,�ry ,,. a�,.✓..,,r,,,,e u�.,,,,i/%/%l!�/%��/l,'/✓/ /�N1iYpl UlO f// ,,.,. 4 1, 1 �(�����a ..:,rr/ld r; i µ;,,,.m.., piio/O//l//�%G i✓i/i/%//ll >Pj�rr'l ,,,r r„err, l � f �� �fs6��(fd l�� rilr !i„mw�m.._. ///lfl�a�/�1�/„ �tl�f/%///l%/////%/ll0✓f�,ci,� r r. r% i,� �J >/7 f r_ /iai���irU�✓i r,-,�/oirrrll la�,/!,����� .; ,�, / � � 101 / 1,,�,/� �l� r in �xry�tyarv+r r1%�rr�r 'f, ��o�rr���ii� ���`7�'� d � �✓!f��;f���i�'�o�,rl�i v,�;�,,,, rrply��rwrnvr�+l�✓E rr")%/i%N/✓isl ��%�i/, ��%//r%,.�Y /i/// �/ ��� 1i j/ �r ��I/�/i✓i l �/i��� 1 f�u�ij� 1 'I I !f �frl�f�11�'� ) l m. rr l j Ir I v r / Location: 1918 Bay PI Description of the photo: from SE corner facing west Photo taken by: Aaron Parrish 2-1-23 I I ��I Y /%//,���� ���)1.�� �?II ,a �"i,1, �t'��1.,�-. a,r',,,�r;, �I: %fir••• .>Ma.��r„r �" S 9 4�y4 �d'I�, r,�� ,,,, I I //iiirr/,,,,,;rr, ,,,,,r,, ��� 1' I.,l r,:/��)i�"/L�� i(���y ra ,.;,I�i ry"P,e?l�l,I,�r t;,1. .. 4 �,l��i. ����f�a l�///d/r,�%��lr�Rm��/r/�IJ/ts✓1 „r � ����✓r��`!'rltl'�"�����""�����'1��7r����1f4fIJ J�✓%',ro�,r AS"I,�t°y' ,. d.. � 1 r 1 i,, I I /a Location: 1918 Bay PI Description of the photo: from SW corner facing east Photo taken by: Aaron Parrish 2-1-23 . y r r r NOr �r �t N +1 g r mulluuu uuni y# r ' � �,,"6.., �1?r tl IIf lfl✓/�/!�����%%�/Ni��//✓r�j�y /r// r t� �f rr1J///ar+ ���,e r/i/eri r' ✓//rliaulr J {r r, V4 ,,,f/1,1��/f�/�/n ///�1/r/ 'I//I/%�/IJ/rr��✓f{����r�r I„� �NI�'�'f, ��rr�/yJr/,i�����J//iNl/i/�/////��,�/////�J�r.;.�;�%//fN,N�N If�.,//%I✓ri//!/ry��Y'"r �lil , �� (��n rlrl�r�/ii/i/�//rir�/ir/ray! rr%/irk('/�%r��/yN��,%i/'''if����r�y/'✓��1,ar{//P V�"Ipul er'�,,,, ;.:., � %,r,Y u.,, �r(9��i��l�/{��j'/Uf r//a./�t./��//,P FIII7 rrr�%jf?//a rya//fir�///rl✓�/�rrr�Y,f �la; , {,rY!!�,1;,l'%'ll�',1'/ /r rr,%�llr///�,/ll,/>y/ r ✓lull �Hry(y%i���iil/cirri(r//J/rir6�f�jr/�r?�,�t//i luu� /1 �0'Nri r'�///(f I 'r/ry//���/%�,//i r dot✓'V:'rri/ilr,rr':7'"bf a�r///(�/iF/ ::�/�l�r"%/��%/Ir'r, ,r r{1/,✓l,,,r j, r!0%�i; I,,,,,�/�r�f��y, /r,�i//'!//r,/,?!d/i/r/i,.r/ ✓r/a�;�ur/l! 0 .. `yr. r„�,�//�J„i Jl'I/,P?,�� rrf✓Y, f�>/1����f,,,1��1rJ71�"�Yii/1%/�If�/rr��;i, `o Y„ r d , 1'+ �(!r�✓i1�4' !r',"��r p1���rr/r��//err� ,r,�r/r!�af�I�„�r",����✓Irr�rr"/1�9rl�ri,,j-,, , V a/''r '�`! ',r�. ;�uG,J,��7".I��I !,'fy �u/fr r;a f,/r/�r�i/1.:�aerllr��,!y!iiir.;-.. a%�✓�r�,,�Y{"'" I 3r��y,�.'�f�il.i7Y J�J. Location: 1918 Bay PI Description of the photo: From south corner facing north Photo taken by: Aaron Parrish 2-1-23 r , r- V Ip � r ��J ��; ,f I mrrxmi,nm,,r,m � nnm nrr nm,V r�rJm r�„rra raw pQ, y, Location: 1918 Bay P1 Description of the photo: from east side facing west Photo taken by: Aaron Parrish 2-1-23