Loading...
HomeMy WebLinkAboutBLD2008-00315 CERTIFICATE OF OCCUPANCY Jefferson County Department of Community Development 621 Sheridan Street Port Townsend, WA 98368 (360)379-4450 FAX (360)379-4451 (800) 831-2678 PERMIT #: BLD08-00315 SITE ADDRESS: 354 PIPER RD Issue Date: 09/26/2008 QUILCENE, 98376 Final Date: 10/5/2009 APPLICANT: GARTH LOUIS PHONE: 503-534-9402 DEBORAH L LOUIS 3271 FIR RIDGE RD LAKE OSWEGO OR 97035-2642 SUBDIVISION: TURNER SHORT PLAT Block: Lot: 1 PARCEL NUMBER: 701201011 Section: 20 Township: 27 N Range: 01 W PROJECT DESCRIPTION: NSFR W/ DECKS and Shoreline Exemption Permit THE PROJECT LISTED ABOVE COMPLIES WITH THE REQUIREMENT OF THE BUILDING CODE 2006 EDITION. OCCUPANCY GROUP: R-3 TYPE OF CONSTRUCTION: 5N SPRINKLER SYSTEM yes jho THE PROJECT PASSED ITS FINAL INSPECTION AND RECEIVED FINAL SIGN OFF ON 10/5/2009 I:\F_BLD_Occupancy.rpt 10/29/19 r _ • • Jefferson County Building Division Permit Number: BLD08-00315 Applicant: LOUIS BUILDING PERMIT INSPECTION APPROVALS applicable Code: 2006 International Building Codes To schedule inspections, call (360)379-4455 no later than 7:00 AM the day of the inspection. Requests received after 7:00 AM will not be scheduled for that day's inspections. ELECTRICAL PERMITS are issued by the Washington State Department of Labor& Industries. The electrical permit must be signed off by the State Inspector prior to the County's Framing Inspection Inspection Item Date Approval Signature Notes Setbacks 11/314 Al Minimum setback from Piper Road right-of-way shall be 20 feet. Minimum side yard setbacks shall be 5 feet. Minimum setback from shoreline toe of slope shall be 91 feet. Erosion Control f//3/0 9 /1,1 SEE CONDITION I. Foundation Footing ///3/bq g)pi Footing Drains i/�7/©149/ Foundation Stem Wall Under Floor Framing Straps(hold downs) o� V c L7(13 Ext. Shear Wall Nailing (� r 5-- Rough-in Plumbing `C/ ( Framing 5'4ct Aye ,w8'1! 4 Pik Airseal Lift C6 , Insulation:Walls j1f Insulation: Floors Insulation:Ceiling 4/4 0i Int. Shear Wall Nailing e' _Of Wallboard Nailing Gas Line: Interior ��$•� Gas Line: Exterior /V q, Propane Tank 14j ,4 Heat/Chimney Clearance Y Ai\Drywell/Alt Drainage ENGINEERED 6WAT R LAN. REQUIRES FINAL LETTER FROM ENGINEER PRIOR TO FINAL BLDG SIGN 01=F. Address Posted co—c✓q [1114A l 54-0 k-4-) FINAL INSPECTION /�._�,-_C( 4,-(> Se E Cbnn4 tun a i 3 t xo. Tb 1 FINAL INSPECTION MUST BE APPROVED PRIOR TO BUILDING BEING OCCUPIED THIS PERMIT IS VALID FOR ONE YEAR — lik Revviewiew Type:PERMIT APPLICAON ML y e: I pe: I Jefferson County Department of Community Development 621 Sheridan Street Port Townsend, WA 98368 PERMIT #: BLD08-00315 Received Date: 7/16/2008 SITE ADDRESS: 354 PIPER RD QUILCENE, 98376 OWNER: GARTH LOUIS PHONE: 503-534-9402 DEBORAH L LOUIS 3271 FIR RIDGE RD LAKE OSWEGO OR 970352642 TURNER SHORT PLAT SUBDIVISION: Block: Lot: 1 PARCEL NUMBER: 701201011 Section: 20 Township: 27 N Range: 01 W CONTRACTOR: 2ND HOME SERVICES LLC PHONE: 360-609-0636 11 PASSAGE WAY SKAMANIA WA 98648 Contractor's License 2NDHOHS969NO Expires 8/20/2008 REPRESENTATIVE: BILL DAUENHAUER PHONE: 360-385-9532 1329 HUDSON ST PORT TOWNSEND WA 98368 PROJECT DESCRIPTIOr NSFR W/ DECKS TYPE OF WORK RES SQUARE FOOTAGE: TYPE OF IMP NEW MAIN: 1,453 VALUATION 245,000.00 ADD'L: 225 HEAT TYPE: EEE CODE EDITION: 2006 HEAT BASE: 282 HEAT TYPE: OCCUPANCY: R-3 UNHEATED: #OF STORIES: OCCUPANCY: OTHER: CONST TYPE: 5N GARAGE: SHORELINE: CONST TYPE: DECK: 630 SETBACK: BANK HEIGHT: SEWAGE DISPOSAL: CON WATER SYSTEM: PWELL BEDROOMS: BATHROOMS: Exist: 0 Exist: 0 Prop: 3 Prop: 2 Total: 3 Total: 2 Routing Date: 1 . Ik Type Amount Paid By: Date: Receipt: Approved/Date Permit $1,805.75 LYK 07/16/08 100674 APPR ., Plan Check $1,173.74 LYK 07/16/08 100674VEL . State Building Code $4.50 LYK 07/16/08 100674 SEPR(p 2008 Potable Water Application $59.00 LYK 07/16/08 100674 Total: $3,042.99 Jefferson County Planning &Building Department • • CONDITIONS for Building Permit# :BLD08-00315 1.) CONSTRUCTION ENTRANCES SHALL BE STABILIZED WHEREVER TRAFFIC WILL BE LEAVING A CONSTRUCTION SITE AND TRAVELING ON PAVED ROADS OR OTHER PAVED AREAS WITHIN 1,000 FEET OF THE SITE. THE ENTRANCE SHALL BE CONSTRUCTED ON A FIRM COMPACTED SUBGRADE. QUARRY SPALLS (OR HOG FUEL) SHALL BE ADDED IF THE PAD IS NO LONGER IN ACCORDANCE WITH THE SPECIFICATIONS. (BMP C105, 2005 DOE STORMWATER MANUAL). ANY SEDIMENT THAT IS TRACKED ONTO PAVEMENT SHALL BE REMOVED BY SHOVELING OR STREET SWEEPING. THE SEDIMENT COLLECTED BY SWEEPING SHALL BE REMOVED OR STABILIZED ON STIE. ANY QUARRY SPALLS THAT ARE LOOSENED FROM THE PAD, WHICH END UP ON THE ROADWAY SHALL BE REMOVED IMMEDIATELY. UPON PROJECT COMPLETION AND SITE STABILIZATION, ALL CONSTRUCTION ACCESSES INTENDED AS PERMANENT ACCESS FOR MAINTENANCE SHALL BE PERMANENTLY STABILIZED. 2 ) PRIOR TO FINAL BUILDING OCCUPANCY, PROPONENT SHALL SUBMIT A WRITTEN LETTER FROM ZENOVIC AND ASSOCIATES STATING THAT THE STORMWATER FACILITY HAS BEEN CONSTRUCTED IN ACCORDANCE WITH THE REQUIREMENTS OF THE "STORMWATER POLLUTION PREVENTION PLAN" DATED JUNE 2, 2008 AS SIGNED BY TRACY D. GUDGEL OF ZENOVIC AND ASSOCIATES. 3.) PRIOR TO OCCUPANCY & BUILDING FINAL - FINAL APPROVAL OF SEPTIC SEP05-00334 IS REQUIRED. MUST MEET ALL CONDITIONS OF SEPTIC PERMIT. 4.) ALL COMPONENTS OF THE SEPTIC SYSTEM ARE TO BE COMPLETELY PROTECTED FROM VEHICULAR TRAFFIC OR MECHANICAL DISTURBANCE. 5.) 10' SEPARATION REQUIRED BETWEEN A WATER LINE AND ALL PORTIONS OF THE ONSITE SEWAGE SYSTEM; EFFLUENT TRANSPORT LINE, TANKS, TREATMENT AND DISPOSAL COMPONENTS. 6.) To help prevent seawater from intruding landward into underground aquifers, all new development activity on Marrowstone Island, Indian Island and within 1/4 mile of any marine shoreline shall be required to infiltrate all stormwater runoff onsite. 7.) The property owner shall comply with Water Conservation Measures (per list maintained by the UDC Administrator). 8.) A Geotechnical Report dated July 7, 2006 prepared by Stratum Group was submitted in conjunction with this application. The report addressed the stability of the geologic hazard area. The shoreline bank height is 91 feet and the submitted site plan identifies a 91 foot setback from toe of slope. 9.) Critical Aquifer Recharge Areas may require special protection measures to mitigate water quality degradation. The submitted proposal does not require additional aquifer protection measures. However, during construction the project shall follow the Best Management Practices (BMPs) and facility design standards as identified and defined in the Stormwater Management Manual for the Puget Sound Basin. 10.) An Engineered Stormwater Plan Ilikeen submitted and approved by the Dep•ent of Community Development. Once the subject permit has been issued the applicant shall fully implement the provisions of the submitted plan and contact the Jefferson County Department of Community Development to arrange a schedule to inspect the property for plan compliance. A Certificate of Occupancy will not be issued until the Department verifies plan compliance. No clearing for roadways or utilities shall occur on the project site until clearing necessary for the installation of temporary sedimentation and erosion control measures have been completed. 11.) Outdoor residential storage shall be maintained in an orderly manner and shall create no fire, safety, health or sanitary hazard. 12.) Not more than 2 unlicensed vehicles shall be stored on any lot unless totally screened from view of neighboring dwellings and rights-of-way. Such screening shall meet all applicable performance and development standards specific to the district in which the storage is kept, and shall be in keeping with the character of the area. Screening shall meet the requirements of Chapter 18.30 JCC. Outdoor storage of 3 or more junk motor vehicles is prohibited except in those districts where specified as an automobile wrecking yard or junk (or salvage) yard and allowed as a permitted use in Table 3-1 or Chapter 18.18 JCC, and such storage shall meet the requirements of JCC 18.20.100, Automobile wrecking yards and junk (or salvage) yards. In no case, shall any such junk motor vehicles be stored in a critical area. 13.) A minimum of two (2) on-site parking spaces shall be provided for the single family residence. 14.) Maximum lot coverage is not to exceed 25%. Lot coverage is defined as amount of impervious surface which includes roof tops, driveways, concrete, etc. 15.) The building height is not to exceed 35 feet. 16.) Minimum setback from Piper Road right-of-way shall be 20 feet. Minimum side yard setbacks shall be 5 feet. Minimum setback from shoreline toe of slope shall be 91 feet. 17.) Exterior lighting for residential uses shall not exceed twenty feet(20') in height from the finished grade, excepting when such lighting is an integral part of a building or structure. Ground level lighting is encouraged. 18.) Lighting fixtures shall be designed and hooded to prevent the light source from being directly visible from outside the boundaries of the property. The intensity or brightness of all lighting, during construction and after project completion shall not adversely affect the use of surrounding properties or adjoining rights-of-way. 19.) Residential developers and individual builders shall be required to preserve shoreline vegetation and reduce the associated risk of erosion during construction and any future activity which may impact the stability of the shoreline. 20.) The applicant shall fully adhere to all conditions and requirements of the eagle habitat management plan as signed by WDFW on August 27, 2008 and applicant on August 30 2008. 06/11/2008 17:46 360382 TPI • PAGE 03/03 ' i .. O JEFFERSON COUNTY ( f Iv �. DEPARTMENT QF GOMMUNty DEVELOP __ '" `4 621 Sheridan Street•Port ToWnserr DEVELOPMENT 140 . 360l379 4450. 3ti0/379 4451 Fax �Alashington 98368 • .,..tt7 www.co.jefferson.wa.us/cammdevelOpme I L Master Permit Application • I Y l ; - = �1 Project Description(include separate sheets as necessa •: ' Tax Parcel Number: 7 r'l.2 o J 0/1 Property Size: ) ,07 a(,Z.z S fee(acres/square Site Address and/or Directions to Property: S 4 I t7�2 © `/ t) 0te/�Z--- .0e- t CO /1- c1N3-7<-- _ Property Owriar(s)of Record: (.N 1 ._ Telephone: 9 Z Fax 1 . V Mailing Address: �,G�..ZI / � email Applicant/Agent(if different from owner): /3iZ_L- D4u.•N/t Rcil /t Telephone: 3 Ss"— 2,472 7 ,,99 Mailing Address: / Cec(50/1/ Fax g� email:(.1b5 N Jt Cull�SOQ of•Ce�� fi c�rt�? DwN S e,•,r � What mind of Permit?(Check each box that applies Bu ing Q Critical Areas Stewardship Plan ❑ Demolition Permit Q Variance(Minor,Major or Reasonable Economic Use Single Family O Garage Attached/Detached 0 Conditional Use[C(a),C(d),or CJ"° ) • ❑ Manufactured Home El Modular ❑Discretionary"D"or Unnamed Use Classification ❑ Commercial` ❑Special Use(Essential Public Facilities)** ❑ Addresgof Use 0 Boundary Line Adjustment 0 Road Approach ❑Short Plat"* ❑Home Business 0 Cottage Industry ❑Binding Site Plan"" ❑Propane 0 LongPlat**. 0 Sign ❑Planned Rural Residential Development(PRRD)/Amendments" 0 Allowed"Yes"Use Consistency Analysis ❑Plat Vacation/Alteration"❑Stormwater Management 0 Shoreline Master Program Exem tion/Permit Revisions'" El Site Plan Approval Advance Determination SPAAp y °g P ❑Temporary Use ( ) ❑Shoreline Management Substantial Development** El Wireless Telecommunication* ❑Shoreline Management Variance ❑Forest Telecommunication munica ion of Six Year Moratorium 0 Comprehensive Plan/UDC/Land Use District Map Amendment *May require a Pre - ©JeffersTree en Shoreline Master Program Amendment Applfaation Conference Cl Tree Vegetation Request "R ulres a Pre-A 'leaner,Conference Please identify any other local,state or federal permits required for this proposal,if known: I hereby designate t7ESiGNATION OF AGENT �uc/a to act as my agent in matters relating to this application for p rmit(s). OWNER SIGNATURE �� ,Q_.. _ _ Date: �/ J -0 t� By signing this application form,the owner/agent attests that the information provided herein,and in any attachments,IS true and correct to the best of his,her or its knowledge, Any material falsehood or any omission of a material fact made by the owner/agent with respect to this application packet may result in this permit being null and void. 1 further agree to save,Indemnify and hold harmless Jefferson County against all liabilities,judgments,court costs,reasonable attorney's fees and expenses which may in any way accrue against Jefferson County as a result of or in consequence of the granting of this permit. I further agree to provide access and right of entry to Jefferson County and its employees,representatives or agents for the sole purpose of application review and any required later inspections. Staffs access and right of entry will be assumed unless the applicant informs the County In writi g at the time of the a I ti t he-o h ants prior notice. Signature: cl � Date: _/Z y C - The action or actions Applicant will undertake as a result of the issuance of this permit may negatively impact upon one or more threatened or endangered species and could lead to a potential"take"of an endangered species as those terms are defined in the federal law known as the "Endangered Species Act"or"ESA.'Jefferson County makes no assurances to the applicant that the actions that will be undertaken because this permit has been issued will not violate the ESA. Any Individual,group or agency can file a lawsuit on behalf of an endangered Species regarding your action(s)even if you are In compilan with the Jefferson County development code.The Applicant acknowledges that he,she or it holds individual andsfttrl non-tran ble 1 . . adhering to and complying with the ESA. The Applicant has read this disclaimer and signs an des it below. Signature: AA-IT nature: // j/(`"S�,�y - Date: 6 '—/ 2_"0 G:\FetrnitCenter\###FORMS###\DRD FOB\Master Pe mit Application 5-29-084oc I. BUILDER STATEMENTd ., The signer of this statement does hereby certif t they ar the Owners of the parcel referenced herein,that they are not licensed contractors and that ::: e assusponsibiliy flheenral C *tor for the proposed project. /ure: i ,k14 A._ {. y LA -�i Date: 2/ S//6 GENERAL CONTRACTOR OR MANUFACTURED HOME INSTALLER: PHONE: FAX: AND No14-? Se tvrce 5 (« 1 (3 P) &n 3 0b36 ( ) MAILING ADDRESS: // P�f.560'4' uv,/„9/Z.I/2 t) f(�t. EMAIL: CONTRACTOR'S LICENSE y8'(d�8 WAINS NUMBER: aI✓O h1 OHS q C t,1/,h NUMBER ARCHITECT/ENGINEER: // / PHONE ( ) FAX:( ) MAILING ADDRESS: EMAIL Project Type: Frame Type: Bathrooms: Shoreline: Type of Sewage Disposal: 97New Ed/Wood Existing: ❑ Sewer ❑ Addition 0 Steel Proposed: ; Bank 0 Community System ❑ Alteration/Remodel 0 Concrete Total: 2-_, Height: 0 Individual System S a0_'33t� ❑ Repair 0 Masonry SEP Permit#- / ❑ Demolition 0 Other: Bedrooms: Water Supply: Existing: Setback: rivate well 0 Two Party Type of Heat: Proposed'fotal: 3 ❑ Public 4// Name of System: If this is a Commercial Protect you must answer the following: _ Number of Parking Spaces: Current Proposed: Number of ADA-Parking Spaces T ‘," I: , Number of occupants(includes owners,tenants,employees,etc) Current Proposed _ ' •f '' ,1 IBC Occupancy: IBC Type of construction: Will you have Food Servile?YYes / No If this is a Pro ane T and/or A liance Installation ermit mark all items below that a lyi. jut_ 6 2008 , ,i I Underground Tank ove ground Tank Size of Propane Tank: 1 Heat Stove i Cook Stove I Woodstove i Fireplace Insert i Hot Water T k 1 Pellet Stovq I Other Is this appliance being installed in a Manufactured/Mobile Home? Yes / No When applying for a permit to install a propane tank you must also submit site plan showing all of the buildings,all property . lines, tank location and size,distances from the propane tank to all property lines,buildings and septic system components, including the reserve area. _ • iv v Square Footage Current Proposed For.Office Use Only Amount"' `;;Revisi Main Floor Heated' 1�:.2 (_.; EH Bld App Review: ,- 1 S3 1 I k) Floor Heated `�`�-,� �l..?-- Consistency Review: Other Heated Base fee: c' Mezzanine 4 --- ) : 310-7. 0(D Heated Basement Plan Check fee: L( A)- Z.z i l l `l. Unheated Basement State Surcharge fee: -A Other Unheated Pot Water Review fee: C e- Garage/Carport SUBTOTAL ,�1 79 < s JI D Decks �3 C 14:� � ,4 ;�. 911/Rd Approach fee: �', �� �°�Lg�-j.� Other TOTAL: $ � (p9 Receipt Number: 100/_�C�^7CI l Y< :;, Cash/Check Number: ESTIMAT OST(REQUIRED) Date: •Fair m et va, e of all labor and materials founda n to finish 7' 1 '7* 4 S Ob 0Initials: _IS G:\PermitCenter\###FORMS###\DRD FORMS\Master Pemvt Application 5-29-08.doc s� µ Stormwater Pollution Prevention Plan Stormwater Pollution Prevention Plan For Garth & Debra Louis Prepared For Jefferson County PERT # :9I.k 08 - 071J Z 1:F F UI S U !; CIAMPI KO Owner/Developer/Operator Garth & Debra Louis. 3271 SW Fir Ridge Lake Oswego, OR 97035 Project Site Location Between Piper Road and Dabob Bay in Quilcene, WA 98376 I Site Inspector5d oo Unknown .t,4 6'Gu+-- 4zr‹,of`NASh , S tier sr SWPPP Prepared By ''t- ?,z Zenovic and Associates ' •' 4. , a 301 East 6th Street Suite 1 O s`27T7 44 Stormwater i��"y `� Port Angeles, WA 98362 �S 9Fcis,EAw . Required ��i w, ii�,i �ONAI. , q ,. 360-417-0501 SWPPP Preparation Date '( `` V June, 2008 Approximate Project Construction Dates Unknown APPROVED STORM WATER PLAN Custom 1EFFERSO l! Y so«ows Nw DEPT.OF Direct(360)385 3427 SIGNATI;RE: 1 y , r 4 Stormwater Pollution Prevention Plan Contents 1.0 Introduction 4 2.0 Site Description 7 2.1 Existing Conditions 7 2.2 Proposed Construction Activities 9 3.0 Construction Stormwater BMPs 13 3.1 The 12 BMP Elements 13 3.1.1 Element#1 —Mark Clearing Limits 13 3.1.2 Element#2 — Establish Construction Access 14 3.1.3 Element#3 —Control Flow Rates 15 3.1.4 Element#4— Install Sediment Controls 15 3.1.5 Element#5 —Stabilize Soils 17 3.1.6 Element#6—Protect Slopes 18 3.1.7 Element#7—Protect Drain Inlets 19 3.1.8 Element#8 — Stabilize Channels and Outlets 20 3.1.9 Element#9—Control Pollutants 21 3.1.10 Element#10—Control Dewatering 24 3.1.11 Element#11 —Maintain BMPs 24 3.1.12 Element#12 —Manage the Project 24 4.0 Construction Phasing and BMP Implementation 29 5.0 Pollution Prevention Team 31 5.1 Roles and Responsibilities 31 5.2 Team Members 32 6.0 Site Inspection 32 6.1 Site Inspection Frequency 34 6. 2 Site Inspection Documentation 34 7.0 Recordkeeping 34 7.1 Site Log Book 34 7.2 Records Retention 35 7.3 Access to Plans and Records 35 • ' 7.4 Updating the SWPPP 35 Appendix A—Site Plans 36 Appendix B—Construction BMPs 37 • Appendix C—Alternative BMPs 62 Appendix D—General Permit 63 Appendix E—Site Inspection Forms (and Site Log) 64 2 r' • • 4 Stormwater Pollution Prevention Plan Site Inspection Form 66 Appendix F—Engineering Calculation 72 Appendix A Site plans • Vicinity map (with all discharge points) • Site plan with TESC measures Appendix B Construction BMPs • Possibly 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 Alternative Construction BMP list • List of BMPs not selected, but can be referenced if needed in each of the 12 elements Appendix D General Permit(if necessary) Appendix E Site Log and Inspection Forms Appendix F Engineering Calculations (if necessary) • Flows 3 • Stormwater Pollution Prevention Plan 1.0 Introduction This Stormwater Pollution Prevention Plan(SWPPP)has been prepared as part of the Jefferson County stormwater permit requirements for the construction of a single family residential home and driveway. The site is located on the east side of Quilcene,just east of Piper Road bordering Dabob Bay. The existing site is a 2.07-acre lot which is undeveloped. The proposed development consists of installation of stormwater management infrastructure and construction of a single family residential home. Stormwater runoff from the gravel driveway will be dispersed among a vegetated buffer sufficient in length to consider the runoff as infiltrated into the ground. Stormwater from the roof of the proposed house will be collected in the gutters and piped to an infiltration trench on-site. 100% of the on-site stormwater from the house and driveway will be infiltrated. The purpose of this SWPPP is to describe the proposed construction activities and all temporary and permanent erosion and sediment control (TESC) measures, pollution prevention measures, inspection/monitoring activities, and recordkeeping that will be implemented during the proposed construction project. The objectives of the SWPPP are to: • Implement Best Management Practices (BMPs) to prevent erosion and sedimentation, and to identify, reduce, eliminate or prevent stormwater contamination and water pollution from construction activity. • Prevent violations of surface water quality, ground water quality, or sediment management standards. • Prevent, during the construction phase, adverse water quality impacts including impacts on beneficial uses of the receiving water by controlling peak flow rates and volumes of stormwater runoff at the Permittee's outfalls and downstream of the outfalls. 4 l f • • Stormwater Pollution Prevention Plan 2.0 Site Description 2.1 Existing Conditions The proposed site is located between Piper Road and Dabob Bay in Quilcene, Washington. A site vicinity map is located in Appendix A. The site is 2.07 acres in size and is currently undeveloped except for a gravel driveway, well and stairway to beach. The topography of the site is such that it has constant slope, approximately 20%, to the east before you reach the bluff where it drops down approximately 90 feet to Dabob Bay. Surficial soils consist of 12 inches of a dark brown sandy loam underlain by an 18 inch layer of even more dense gravelly sandy loam. Below that is a very deep layer of light brown/gray fine sandy loam. During the wet season water is expected to be at a depth of approximately 72". At its undeveloped state the site has little no runoff due to evapotranspiration and infiltration. The only critical area on site is the bluff leading down to Dabob Bay. The slope is very steep and poises a high erosion risk and is a potential landslide area. The bluffs are currently stable and will be protected during the life of construction. 2.2 Proposed Construction Activities The proposed development includes the construction of a single family residential home and stormwater management system. Construction activities will include site preparation, TESC installation, excavation for stormwater drainage, building foundation and minimal site grading. The increase in stormwater runoff from the house roof area will be infiltrated on-site by piping the roof downspouts to an infiltration trench where the water can slowly be infiltrated back into the soil. Runoff from the gravel driveway will be dispersed over a large area of natural vegetation where it can infiltrate. 5 Stormwater Pollution Prevention Plan Runoff analysis was completed using the 2005 Stormwater Management Manual for Western Washington. The stormwater drainage plan and calculations are attached in Appendix F. • Total site area: 2.07 acres • Percent impervious area before construction: 0 % • Percent impervious area after construction: 6.7 % • Disturbed area during construction: 0.2 acres • Disturbed area that is characterized as impervious (i.e., access roads, staging, parking): 0..139 acres • 2-year stormwater runoff peak flow prior to construction 0.276 cfs (existing): • 10-year stormwater runoff peak flow prior to construction 0.499 cfs (existing): • 100-year stormwater runoff peak flow prior to construction 0.884 cfs (existing): • 2-year stormwater runoff peak flow after construction: 0.258 cfs • 10-year stormwater runoff peak flow after construction: 0.465 cfs • 100-year stormwater runoff peak flow after construction: 0.825 cfs All stormwater flow calculations are provided in Appendix F. 6 • • 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 will be clearly marked before land-disturbing activities begin. Trees that are to be preserved, as well 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 BMPs relevant to marking the clearing limits that will be applied for this project include: • Preserving Natural Vegetation (BMP C101) For critical areas siltation fencing will be used to limit runoff from leaving the site, it will also serve to limit the amount of natural vegetation that is disturbed. For the rest of the site, ground will remain unbroken in areas that are not to be developed creating a buffer from neighboring properties. 3.1.2 Element#2 —Establish Construction Access Construction access or activities occurring on unpaved areas shall be minimized, yet where necessary, access points shall be stabilized to minimize the tracking of sediment onto public roads, and wheel washing, street sweeping, and street cleaning shall be employed to prevent sediment from entering state waters. All wash wastewater shall be controlled on site. The specific BMPs related to establishing construction access that will be used on this project include: • Stabilized Construction Entrance (BMP C105) A construction entrance shall be build off of Piper Road; all traffic shall be limited to this entrance. 3.1.3 Element#3—Control Flow Rates In order to protect the properties and waterways downstream of the project site, stormwater discharges from the site will be controlled. The specific BMPs for flow control that shall be used on this project include: • Infiltration Trench 7 • • f ' Stormwater Pollution Prevention Plan Runoff from the site during construction will be very minimal. The permanent stormwater detention facilities shall be constructed first and all stormwater during construction shall be directed to it. 3.1.4 Element#4— Install Sediment Controls All stormwater 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 specific BMPs to be used for controlling sediment on this project include: • Silt Fence (BMP C233) • Storm Drain Inlet Protection (BMP C220) Silt Fence shall be installed 40' west of the bluff and as long as necessary to make sure all runoff from site passes through the fence. Any catch basins installed during construction will be protected to control turbidity. In addition, sediment will be removed from paved areas in and adjacent to construction work areas manually or using mechanical sweepers, as needed, to minimize tracking of sediments on vehicle tires away from the site and to minimize washoff of sediments from adjacent streets in runoff. 3.1.5 Element#5—Stabilize Soils Exposed and unworked soils shall be stabilized with 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 C120) • Mulching (BMP C121) All stockpiled soils shall be stabilized from erosion, protected with sediment trapping measures, and where possible,be located away from storm drain inlets, waterways, and drainage channels. 3.1.6 Element#6— Protect Slopes All cut and fill slopes will be designed, constructed, and protected in a manner than minimizes erosion. The following specific BMPs will be used to protect slopes for this project: • Straw Wattles (BMP C235) 8 t • • Stormwater Pollution Prevention Plan In general, cut and fill slopes will be stabilized as soon as possible and soil stockpiles will be temporarily covered with plastic sheeting 3.1.7 Element#7—Protect Drain Inlets All storm drain inlets and culverts made operable during construction shall be protected to prevent unfiltered or untreated water from entering the drainage conveyance system. However, the first priority is to keep all access roads clean of sediment and keep street wash water separate from entering storm drains until treatment can be provided. Storm Drain Inlet Protection (BMP C220) will be implemented for all drainage inlets and culverts that could potentially be impacted by sediment-laden runoff on and near the project site. The following inlet protection measures will be applied on this project: • Catch Basin Filter(socks) Catch Basin Filter Socks shall be installed in any catch basin which is to be used to collect runoff during construction. 3.1.8 Element#8—Stabilize Channels and Outlets Where site runoff is to be conveyed in channels, or discharged to a stream or some other natural drainage point, efforts will be taken to prevent downstream erosion. The specific BMPs for channel and outlet stabilization that shall be used on this project include: • Outlet Protection (BMP C209) There are no outlets to protect on-site, but if at anytime there is one created; a 5 foot by 5 foot quarry spall pad shall be constructed at the outfall of all pipes. 3.1.9 Element#9—Control Pollutants All pollutants, including waste 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, well organized, and free of debris. If required, BMPs to be implemented to control specific sources of pollutants are discussed below. Vehicles, construction equipment, and/or petroleum product storage/dispensing: • All vehicles, equipment, and petroleum product storage/dispensing areas will be inspected regularly to detect any leaks or spills, and to identify maintenance needs to prevent leaks or spills. • On-site fueling tanks and petroleum product storage containers shall include secondary containment. 9 • • S r Stormwater Pollution Prevention Plan • Spill prevention measures, such as drip pans, will be used when conducting maintenance and repair of vehicles or equipment. • In order to perform emergency repairs on site, temporary plastic will be placed beneath and, if raining, over the vehicle. • Contaminated surfaces shall be cleaned immediately following any discharge or spill incident. The facility does not require a Spill Prevention, Control, and Countermeasure (SPCC) Plan under the Federal regulations of the Clean Water Act (CWA). 3.1.10 Element#10—Control Dewatering There will be no dewatering during construction. However, the dewatering of soils known to be free of contamination will trigger BMPs to trap sediment and reduce turbidity. At a minimum, geotextile fabric socks/bags/cells will be used to filter this material if any dewatering does occur on-site. 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 with each particular BMP's specifications. Visual monitoring of the BMPs will be conducted at least once every calendar week and within 24 hours of any rainfall event that causes a discharge from the site. If the site becomes inactive, and is temporarily stabilized, the inspection frequency will be reduced to once every month. All temporary erosion and sediment control BMPs shall be removed within 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 permanently stabilized. 3.1.12 Element#12 —Manage the Project Erosion and sediment control BMPs for this project have 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. 10 • • Stormwater Pollution Prevention Plan • Minimize 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 will incorporate the key components listed below: As this project site is located west of the Cascade Mountain Crest, the project will be managed according to the following 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. • Revegetation 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 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: ❑ Site conditions including existing vegetative coverage, slope, soil type, and proximity to receiving waters; and ❑ Limitations on activities and the extent of disturbed areas; and ❑ Proposed erosion and sediment control measures. • Based on the information provided and/or local weather conditions, the local permitting authority may expand or restrict the seasonal limitation on site disturbance. • The following activities are exempt from the seasonal clearing and grading limitations: 11 • Stormwater Pollution Prevention Plan ❑ 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 o Activities where there is 100 percent infiltration of surface water runoff within the site in approved 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 SWPPP and scheduling the construction work. Inspection and Monitoring • All 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 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 O Assess the effectiveness of erosion and sediment control measures used to control the quality of stormwater discharges. • Whenever 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. Maintaining an Updated Construction SWPPP • This SWPPP shall be retained on-site or within reasonable access to the site. • The SWPPP 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. 12 • • Stormwater Pollution Prevention Plan • The SWPPP shall 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 SWPPP is ineffective in eliminating or significantly minimizing pollutants in stormwater 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 within seven (7) days following the inspection. 13 • s • 1 Stormwater Pollution Prevention Plan 4.0 Construction Phasing and BMP Implementation The BMP implementation schedule will be driven by the construction schedule. The following provides a sequential list of the proposed construction schedule milestones and the corresponding BMP implementation schedule. The list contains key milestones such as wet season construction. The BMP implementation schedule listed below 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 west of the Cascade Mountain Crest. As such, the dry season is considered to be from May 1 to September 30 and the wet season is considered to be from October 1 to April 30. • Mobilize and store all TESC and soil stabilization products • Existing gravel driveway shall serve as the stabilized construction entrance • Install TESC measures • Install Stormwater System • Begin building construction 14 • 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 SWPPP, including the following: • Site Inspector—primary contractor contact, responsible for site inspections (BMPs, visual monitoring, etc.); to be called upon in case of failure of any ESC measures. • Resident Engineer—For projects with engineered structures only (sediment ponds/traps, sand filters, etc.): site representative for the owner that is the project's supervising engineer responsible for inspections and issuing instructions and drawings to the contractor's site supervisor or representative • Emergency Owner Contact—individual that is the site owner or representative of the site owner to be contacted in the case of an emergency. • Non-Emergency Contact—individual that is the site owner or representative of the site owner than can be contacted if required. 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 Number Site Inspector Resident Engineer Chris Hartman 360-417-0501 Emergency Owner Contact Garth or Debra Louis 503-745-6794 Non-Emergency Contact Garth or Debra Louis 503-745-6794 15 • • Stormwater Pollution Prevention Plan 6.0 Site Inspection Monitoring includes visual inspection and documentation of the findings in a site log book. A site log book will be maintained for all on-site construction activities and will include: • A record of the implementation of the SWPPP and other requirements; • Site inspections; For convenience, the inspection form included in this SWPPP includes the required information for the site log book. This SWPPP may function as the site log book if desired, or the forms may be separated and included in a separate site log book. However, if separated, the site log book but must be maintained on-site or within reasonable access to the site and be made available upon request to Jefferson County. All BMPs will be inspected, maintained, and repaired as needed to assure continued performance of their intended function. Since the disturbed area on-site is less then 1 acre in size the Site Inspector will be someone who is knowledgeable in the principles and practices of erosion and sediment control, he/she does not have to be a Certified Erosion and Sediment Control Lead. The name and contact information for the Site Inspector is provided in Section 5 of this SWPPP. Site inspection will occur in all areas disturbed by construction activities and at all stormwater discharge points. Stormwater will be examined for the presence of suspended sediment, turbidity, discoloration, and oily sheen. The site inspector will evaluate and document the effectiveness of the installed BMPs and determine if it is necessary to repair or replace any of the BMPs to improve the quality of stormwater discharges. All maintenance and repairs will be documented in the site log book or forms provided in this document. All new BMPs or design changes will be documented in the SWPPP as soon as possible. 6.1 Site Inspection Frequency Site inspections will be conducted at least once a week. For sites with temporary stabilization measures, the site inspection frequency can be reduced to once every month. 6. 2 Site Inspection Documentation The site inspector will record each site inspection using the site log inspection forms provided in Appendix E. The site inspection log forms may be separated from this SWPPP document, but will be maintained on-site or within reasonable access to the site and be made available upon request from Jefferson County. 16 T i • Stormwater Pollution Prevention Plan 7.0 Recordkeeping 7.1 Site Log Book A site log book will be maintained for all on-site construction activities and will include: • A record of the implementation of the SWPPP and other requirements; • Site inspections; For convenience, the inspection form included in this SWPPP includes the required information for the site log book. 7.2 Records Retention Records of all monitoring information (site log book, inspection reports/checklists, etc.), this Stormwater Pollution Prevention Plan, and any other documentation will be retained during the life of the construction project and for a minimum of three years following the completion. 7.3 Access to Plans and Records The SWPPP and Site Log Book will be retained on site or within reasonable access to the site and will be made immediately available upon request to Jefferson County. A copy of this SWPPP will be provided to the Jefferson County within 14 days of receipt of a written request for the SWPPP. 7.4 Updating the SWPPP 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 waters of the State. The SWPPP will be modified within seven days of determination based on inspection(s) that additional or modified BMPs are neces sary to correctproblems identified, and an updated timeline for BMP p implementation will be prepared. 17 • • 1 , Stormwater Pollution Prevention Plan Appendix A — Site Plans 18 • • Stormwater Pollution Prevention Plan Appendix B — Construction BMPs Preserving Natural Vegetation (BMP C 101) Stabilized Construction Entrance (BMP C 105) Temporary and Permanent Seeding(BMP C 120) Mulching (BMP C121) Storm Drain Inlet Protection(BMP C220) Silt Fence (BMP C233) Straw Wattles (BMP C235) Infiltration Trench 19 • • Stormwater Pollution Prevention Plan 4.1 Source Control BMPs BMP C101: Preserving Natural Vegetation Purpose The purpose of preserving natural vegetation is to reduce erosion wherever practicable. Limiting site disturbance is the single most effective method for reducing erosion_ For example. conifers can hold up to about 50 percent of all rain that falls during a storm. Up to 20-30 percent of this rain may never reach the ground but is taken up by the tree or evaporates_ Another benefit is that the rain held in the tree can be released slowly to the ground after the storm. Conditions of Use • Natural vegetation should be preserved on steep slopes,near perennial and intermittent watercourses or swales. and on building sites in wooded areas. • As required by local governments. Design and Natural vegetation can be preserved in natural clumps or as individual Installation trees. shrubs and vines. Specifications The preservation of individual plants is more difficult because heavy equipment is generally used to remove unwanted vegetation. The points to remember when attempting to save individual plants are: • Is the plant worth saving? Consider the location,species, size, age, vigor.and the work involved. Local governments may also have ordinances to save natural vegetation and trees. • Fence or clearly mark areas around trees that are to be saved. It is preferable to keep ground disturbance away from the trees at least as far out as the dripline. Plants need protection from three kinds of injuries: • Construction Equipment-This injury can be above or below the ground level. Damage results from scarring. cutting of roots, and compaction of the soil. Placing a fenced buffer zone around plants to be saved prior to construction can prevent construction equipment injuries. • Grade Changes-Changing the natural ground level will alter grades, which affects the plant's ability to obtain the necessary air,water. and minerals. Minor fills usually do not cause problems although sensitivity between species does vary and should be checked. Trees can tolerate fill of 6 inches or less. For shrubs and other plants,the fill should be less. When there are major changes in grade. it may become necessary to supply air to the roots of plants. This can be done by placing a layer of gravel and a tile system over the roots before the fill is made. A tile 20 • • Stormwater Pollution Prevention Plan system protects a tree from a raised grade. The tile system should be laid out on the original grade leading from a dry well around the tree trunk. The system should then be covered with small stones to allow air to circulate over the root area. Lowering the natural ground level can seriously damage trees and shrubs. The highest percentage of the plant roots are in the upper 12 inches of the soil and cuts of only 2-3 inches can cause serious injury. To protect the roots it may be necessary to terrace the immediate area around the plants to be saved_ If roots are exposed, construction of retaining walls may be needed to keep the soil in place. Plants can also be preserved by leaving them on an undisturbed. gently sloping mound. To increase the chances for survival, it is best to limit grade changes and other soil disturbances to areas outside the dripline of the plant. • Excavations -Protect trees and other plants when excavating for drainfnelds,power. water, and sewer lines. Where possible. the trenches should be routed around trees and large shrubs. When this is not possible. it is best to tunnel under them. This can be done with hand tools or with power augers. If it is not possible to route the trench around plants to be saved, then the following should be observed: Cut as few roots as possible. When you have to cut, cut clean. Paint cut root ends with a wood dressing like asphalt base paint. Backfill the trench as soon as possible. Tunnel beneath root systems as close to the center of the main trunk to preserve most of the important feeder roots. Some problems that can be encountered with a few specific trees are: • Maple. Dogwood. Red alder. Western hemlock Western red cedar. and Douglas fir do not readily adjust to changes in environment and special care should be taken to protect these trees_ • The windthrow hazard of Pacific silver fir and madronna is high_ while that of Western hemlock is moderate. The danger of windthrow increases inhere dense stands have been thinned. Other species (unless they are on shallow_ wet soils less than 20 inches deep)have a low windthrow hazard. • Cottonwoods. maples. and willows have water-seeking roots. These can cause trouble in sewer lines and infiltration fields. On the other hand, they thrive in high moisture conditions that other trees would not. • Thinning operations in pure or mixed stands of Grand fir. Pacific silver fir. Noble fir, Sitka spruce. Western red cedar, Western hemlock 21 • • • Stormwater Pollution Prevention Plan Pacific dogwood, and Red alder can cause serious disease problems. Disease can become established through damaged limbs, trunks,roots, and freshly cut stumps. Diseased and weakened trees are also susceptible to insect attack. Maintenance • Inspect flagged and'or fenced areas regularly to make sure flagging or Standards fencing has not been removed or damaged. If the flagging or fencing has been damaged or visibility reduced,it shall be repaired or replaced immediately and visibility restored. • If tree roots have been exposed or injured, "prune- cleanly with an appropriate pruning saw or lopers directly above the damaged roots and recover with native soils. Treatment of sap flowing trees (fir, hemlock pine, soft maples) is not advised as sap forms a natural healing barrier. 22 r • • Stormwater Pollution Prevention Plan BMP C105: Stabilized Construction Entrance Purpose Construction entrances are stabilized to reduce the amount of sediment transported onto paved roads by vehicles or equipment by constructing a stabilized pad of quarry spalls at entrances to construction sites. Conditions of Use Construction entrances shall be stabilized wherever traffic will be leaving a construction site and traveling on paved roads or other paved areas within 1.000 feet of the site. On large commercial,highway,and road projects.the designer should include enough extra materials in the contract to allow for additional stabilized entrances not shown in the initial Construction SI PPP. It is difficult to determine exactly where access to these projects will take place: additional materials will enable the contractor to install them where needed. Design and • See Figure 4.2 for details.Note: the 100- minimum length of the Installation entrance shall be reduced to the maximum practicable size when the Specifications size or configuration of the site does not allow the full length(100'). • A separation geotextile shall be placed under the spalls to prevent fine sediment from pumping up into the rock pad. The geotextile shall meet the following standards: Grab Tensile Strength (ASTM D4751) 200 psi min. Grab Tensile Elongation(ASTM D4632) 30% max. Mullen Burst Strength (ASTM D3786-80a) 400 psi min. AOS (ASTM D4751) 20-45(U.S.standard sieve size) • Consider early installation of the first lift of asphalt in areas that will paved: this can be used as a stabilized entrance. Also consider the installation of excess concrete as a stabilized entrance. During large concrete pours. excess concrete is often available for this purpose. • Hog fuel(wood-based mulch)may be substituted for or combined with quarry spalls in areas that will not be used for permanent roads. Hog fuel is generally less effective at stabilizing construction entrances and should be used only at sites where the amount of traffic is very limited. Hog fuel is not recommended for entrance stabilization in urban areas. The effectiveness of hog fuel is highly variable and it generally requires more maintenance than quarry spalls. The inspector may at any time require the use of quarry spalls if the hog fuel is not preventing sediment from being tracked onto pavement or if the hog fuel is being carried onto pavement. Hog fuel is prohibited in permanent roadbeds because organics in the subgrade soils cause degradation of the subgrade support over time. • Fencing(see BN1Ps C103 and C104) shall be installed as necessary to restrict traffic to the construction entrance. 23 II) I 1 Stormwater Pollution Prevention Plan • Whenever possible,the entrance shall be constructed on a fine. compacted subgrade. This can substantially increase the effectiveness r n , 1 . n t r • Whenever possible.the entrance shall be constructed on a firm. compacted subgrade. This can substantially increase the effectiveness of the pad and reduce the need for maintenance. Maintenance • Quarry spans(or hog fuel)shall be added if the pad is no longer in Standards accordance with the specifications. se • If the entrance is not preventing sediment from being tracked onto pavement.then alternative measures to keep the streets free of sediment shall be used. This may include street sweeping. an increase in the dimensions of the entrance.or the installation of a wheel wash. • Any sediment that is tracked onto pavement shall be removed by shoveling or street sweeping. The sediment collected by sweeping shall be removed or stabilized on site. The pavement shall not be 3. cleaned by washing down the street.except when sweeping is ineffective and there is a threat to public safety. If it is necessary to wash the streets.the construction of a small sump shall be considered. The sediment would then be washed into the sump where it can be 1e controlled. • Any quarry spans that are loosened from the pad.which end up on the roadway shall be removed immediately. • If vehicles are entering or exiting the site at points other than the construction entrance(s).fencing(see BSMPs C103 and C104)shall be installed to control traffic. • Upon project completion and site stabilization.all construction accesses intended as permanent access for maintenance shall be permanently stabilized. lika,.....,.-ar ,'r. almtoli p..mll.N.•r[1 It l•warm.ro.r.• IIM FIYrx.M [.•..lwl.•Pal r.rN.l aril'.Y.rr p.d V. i 4• :;to Fur 6,rwle e.- (•• `•,fir .C..1. r..d.M •W-;'•.• Ohh Qf..MI .rt'oval..p 5 � • 'Z.r.111.1.tariM0 1b 1•n.ra rl�oar r npwpn..w. Figure 4.2—Stabilized Construction Entrance 24 • • Stormwater Pollution Prevention Plan BMP C120: Temporary and Permanent Seeding Purpose Seeding is intended to reduce erosion by stabilizing exposed soils_ A well-established vegetative cover is one of the most effective methods of reducing erosion. Conditions of Use • Seeding may be used throughout the project on disturbed areas that have reached final grade or that will remain unworked for more than 30 days. • Channels that will be vegetated should be installed before major earthwork and hydroseeded with a Bonded Fiber Matrix. The vegetation should be well established(i.e.. 75 percent cover)before water is allowed to flow in the ditch. With channels that will have high flows, erosion control blankets should be installed over the hydroseed. If vegetation cannot be established from seed before water is allowed in the ditch, sod should be installed in the bottom of the ditch over hydromulch and blankets. • Retentiontetention ponds should be seeded as required_ • Mulch is required at all times because it protects seeds from heat, moisture loss, and transport due to runoff • All disturbed areas shall be reviewed in late August to early September and all seeding should be completed by the end of September. Otherwise,vegetation will not establish itself enough to provide more than average protection_ • At final site stabilization, all disturbed areas not otherwise vegetated or stabilized shall be seeded and mulched. Final stabilization means the completion of all soil disturbing activities at the site and the establishment of a permanent vegetative cover. or equivalent permanent stabilization measures (such as pavement, riprap,gabions or geotextiles)which will prevent erosion. Design and • Seeding should be done during those seasons most conducive to Installation growth and will vary with the climate conditions of the region. Specifications Local experience should be used to determine the appropriate seeding periods. • The optimum seeding windows for western Washington are April 1 through June 30 and September 1 through October 1. Seeding that occurs between July 1 and August 30 will require irrigation until 75 percent grass cover is established. Seeding that occurs between October 1 and March 30 will require a mulch or plastic cover until 75 percent grass cover is established. • To prevent seed from being washed away, confirm that all required surface water control measures have been installed. 25 Stormwater Pollution Prevention Plan • The seedbed should be firm and rough. All soil should be roughened no matter what the slope. If compaction is required for engineering purposes, slopes must be track walked before seeding. Backblading or smoothing of slopes greater than 4:1 is not allowed if they are to be seeded. • New and more effective restoration-based landscape practices rely on deeper incorporation than that provided by a simple single-pass rototilling treatment. Wherever practical the subgrade should be initially ripped to improve long-term permeability. infiltration. and water inflow qualities. At a minimum, permanent areas shall use soil amendments to achieve organic matter and permeability performance defined in engineered soil1landscape systems. For systems that are deeper than 8 inches the rototilling process should be done in multiple lifts, or the prepared soil system shall be prepared properly and then placed to achieve the specified depth. • Organic matter is the most appropriate form of"fertilizer"because it provides nutrients (including nitrogen. phosphorus, and potassium) in the least water-soluble form. A natural system typically releases 2-10 percent of its nutrients annually. Chemical fertilizers have since been formulated to simulate what organic matter does naturally. • In general. 10-4-6N-P-K(nitrogen-phosphorus-potassium) fertilizer can be used at a rate of 90 pounds per acre. Slow-release fertilizers should always be used because they are more efficient and have fewer environmental impacts. It is recommended that areas being seeded for final landscaping conduct soil tests to determine the exact type and quantity of fertilizer needed. This will prevent the over-application of fertilizer. Fertilizer should not be added to the hydromulch machine and agitated more than 20 minutes before it is to be used. If agitated too much, the slow-release coating is destroyed. • There are numerous products available on the market that take the place of chemical fertilizers. These include several with seaweed extracts that are beneficial to soil microbes and organisms. If 100 percent cottonseed meal is used as the mulch in hydroseed, chemical fertilizer may not be necessary. Cottonseed meal is a good source of long-term. slow-release, available nitrogen_ • Hydroseed applications shall include a minimum of 1,500 pounds per acre of mulch with 3 percent tackifier. Mulch may be made up of 100 percent: cottonseed meal; fibers made of wood,recycled cellulose. hemp, and kenaf: compost; or blends of these. Tackifier shall be plant- based. such as guar or alpha plantago. or chemical-based such as polyacrylamide or polymers_ Any mulch or tackifier product used shall be installed per manufacturer's instructions. Generally. mulches come in 40-50 pound bags. Seed and fertilizer are added at time of application. 26 1 1 • • Stormwater Pollution Prevention Plan • Mulch is always required for seeding. Mulch can be applied on top of the seed or simultaneously by hydroseeding. • On steep slopes, Bonded Fiber Matrix (BFM) or Mechanically Bonded Fiber Matrix (11BFM)products should be used. BFM 13FM products are applied at a minimum rate of 3,000 pounds per acre of mulch with approximately 10 percent tackifier. Application is made so that a minimum of 95 percent soil coverage is achieved. Numerous products are available commercially and should be installed per manufacturer's instructions_ Most products require 24-36 hours to cure before a rainfall and cannot be installed on wet or saturated soils. Generally, these products come in 40-50 pound bags and include all necessary ingredients except for seed and fertilizer. BFMs and MBFMs have some advantages over blankets: • No surface preparation required; • Can be installed via helicopter in remote areas: • On slopes steeper than 2.5:1. blanket installers may need to be roped and harnessed for safety: • They are at least $1,000 per acre cheaper installed. In most cases, the shear strength of blankets is not a factor when used on slopes. only when used in channels. BFMs and MBFMs are good alternatives to blankets in most situations where vegetation establishment is the goal_ • When installing seed via hydroseeding operations, only about 113 of the seed actually ends up in contact with the soil surface. This reduces the ability to establish a good stand of grass quickly. One way to overcome this is to increase seed quantities by up to 50 percent. • Vegetation establishment can also be enhanced by dividing the hydromulch operation into two phases: 1. Phase 1-Install all seed and fertilizer with 25-30 percent mulch and tackifier onto soil in the first lift: 2. Phase 2- Install the rest of the mulch and tackifier over the first lift. An alternative is to install the mulch, seed. fertilizer, and tackifier in one lift. Then, spread or blow straw over the top of the hydromulch at a rate of about 800-1000 pounds per acre. Hold straw in place with a standard tackifier. Both of these approaches will increase cost moderately but will greatly improve and enhance vegetative establishment. The increased cost may be offset by the reduced need for: 1. Irrigation 2. Reapplication of mulch 3. Repair of failed slope surfaces 27 • • Stormwater Pollution Prevention Plan This technique works with standard hydromulch(1y500 pounds per acre minimum) and BFM;MBFIvis (3,000 pounds per acre minimum). • Areas to be permanently landscaped shall provide a healthy topsoil that reduces the need for fertilizers. improves overall topsoil quality, provides for better vegetal health and vitality, improves hydrologic characteristics. and reduces the need for irrigation. This can be accomplished in a number of ways: Recent research has shown that the best method to improve till soils is to amend these soils with compost. The optimum mixture is approximately two parts soil to one part compost. This equates to 4 inches of compost mixed to a depth of 12 inches in till soils. Increasing the concentration of compost beyond this level can have negative effects on vegetal health, while decreasing the concentrations can reduce the benefits of amended soils. Please note: The compost should meet specifications for Grade A quality compost in Ecology Publication 94-038. Other soils, such as gravel or cobble outwash soils. may require different approaches. Organics and fines easily migrate through the loose structure of these soils. Therefore, the importation of at least 6 inches of quality topsoil. underlain by some type of filter fabric to prevent the migration of fines. may be more appropriate for these soils. Areas that already have good topsoil, such as undisturbed areas. do not require soil amendments. • Areas that will be seeded only and not landscaped may need compost or meal-based mulch included in the hydroseed in order to establish vegetation. Native topsoil should be re-installed on the disturbed soil surface before application. • Seed that is installed as a temporary measure may be installed by hand if it will be covered by straw, mulch. or topsoil. Seed that is installed as a permanent measure may be installed by hand on small areas (usually less than 1 acre) that will be covered with mulch. topsoil. or erosion blankets. The seed mixes listed below include recommended mixes for both temporary and permanent seeding. These mixes, with the exception of the wetland mix, shall be applied at a rate of 120 pounds per acne. This rate can be reduced if soil amendments or slow- release fertilizers are used. Local suppliers or the local conservation district should be consulted for their recommendations because the appropriate mix depends on a variety of factors, including location, exposure, soil type. slope, and expected foot traffic. Alternative seed mixes approved by the local authority may be used. 28 • • Stormwater Pollution Prevention Plan Table 4.1 represents the standard mix for those areas where just a temporary vegetative cover is required. Table 4.1 Temporary Erosion Control Seed Mix at Weight Qo Purity Qo Germination Chewings or annual blue grass 40 98 90 Festuca rubra var. cornnmutata or Poa anna Perennial rye- 50 98 90 Loliuni perenne Redtop or colonial bentgrass 5 92 85 Agrostis alba or_igrorti.:tennis White dutch clover 5 98 90 Trifoliurn repent. Table 4.2 provides just one recommended possibility for landscaping seed. Table 4.2 Landscaping Seed Mix +o Weight u o Purity o o Germination Perennial rye blend 7C 98 90 Lolium perenne Chewings and red fescue blend 3C 98 90 Festuca rubra var. cornnrurata or Festuca rubra This turf seed mix in Table 4.3 is for dry situations where there is no need for much water. The advantage is that this mix requires very little maintenance. Table 4.3 Low-Growing Turf Seed Mix t ''eight at Purity oo Germination Dwarf tall fescue(several varieties) 45 98 90 Festuca arundinacea var. Dwarf perennial rye(Barclay) 3C 98 90 Lolium perenne var. barclai Red fescue 20 98 90 Festuca rubra Colonial bentgaass 5 98 90 Agrosris renuis Table 4.4 presents a mix recommended for bioswales and other intermittently wet areas. Table 4.4 Bioswale Seed Mix* is Weight ao Purity 4o Germination Tall or meadow fescue 75-80 98 90 Festuca arundinacea or Festuca elanior Seaside Creeping bentgrass 10-15 92 85 Agr•osri:palustris Redtop bentgaas s 5-10 90 80 Agrastis alba or Agrosti:giganrea ■ ■ ■ llodtfred Briar green. Inc.I vdroreeding Guide Wetland:Seed Mix 29 • Stormwater Pollution Prevention Plan The seed mix shown in Table 4.5 is a recommended low-growing. relatively non-invasive seed mix appropriate for very wet areas that are not regulated wetlands. Other mixes may be appropriate.depending on the soil type and hydrology of the area. Recent research suggests that bentgrass(agrostis sp.)should be emphasized in wet-area seed mites_ Apply this mixture at a rate of 60 pounds per acre. Table 4.5 Wet Area Seed Mix" •o Weight •a Pmit!' 0o Germination Tall or meadow fescue 60-'0 98 90 Fecruca arundinacea ar Ferruca elarior Seaside'Creeping bentgrass 10-15 98 85 dgrosric palustris Meadow foxrail 10- 5 90 80 .dlepocurus prarensic Aisle clover 1-6 98 90 Tr folium$i bridum Redtop bentgrass 1-6 92 85 Agrosris alba _ - - •Modified Bnargreen,Inc.Ht droseeding Guide Ireland:Seed Mix The meadow seed mix in Table 4.6 is recommended for areas that will be maintained infrequently or not at all and where colonization by native plants is desirable. Likely applications include rural road and utility right- of-way. Seeding should take place in September or very early October in order to obtain adequate establishment prior to the winter months. The appropriateness of clover in the mix may need to be considered.as this can be a fairly invasive species. If the soil is amended,the addition of clover may not be necessary. Table 4.6 Meadow Seed Mix •o Weight d o Purity •o Germination Redtop or Oregon bentgrass 2C 92 85 .growl:alba orAgrostis oregonensis Red fescue 7C 98 90 Fe<ruca rubra White dutch clover 1C 93 90 Trtfolium epens Maintenance • Any seeded areas that fail to establish at least S0 percent cover(100 Standards percent cover for areas that receive sheet or concentrated flows)shall be reseeded. If reseeding is ineffective.an alternate method. such as sodding.mulching. or nets/blankets. shall be used. If winter weather prevents adequate grass growth. this time limit may be relaxed at the discretion of the local authority when sensitive areas would otherwise be protected. 30 • • Stormwater Pollution Prevention Plan • After adequate cover is achieved, any areas that experience erosion shall be reseeded and protected by mulch. If the erosion problem is drainage related, the problem shall be fixed and the eroded area reseeded and protected by mulch. • Seeded areas shall be supplied with adequate moisture. but not watered to the extent that it causes runoff. BMP C121: Mulching Purpose The purpose of mulching soils is to provide immediate temporary protection from erosion. Mulch also enhances plant establishment by conserving moisture, holding fertilizer, seed, and topsoil in place, and moderating soil temperatures. There is an enormous variety of mulches that can be used. Only the most common types are discussed in this section. Conditions of Use As a temporary cover measure, mulch should be used: • On disturbed areas that require cover measures for less than 30 days. • As a cover for seed during the wet season and during the hot summer months. • During the wet season on slopes steeper than 3H:1S,'with more than 10 feet of vertical relief. • Mulch may be applied at any time of the year and must be refreshed periodically. Design and For mulch materials_ application rates, and specifications, see Table 4. Installation Note: Thicknesses may be increased for disturbed areas in or near Specifications sensitive areas or other areas highly susceptible to erosion. Mulch used within the ordinary high-water mark of surface waters should be selected to minimize potential flotation of organic matter. Composted organic materials have higher specific gravities (densities)than straw. wood. or chipped material. Maintenance • The thickness of the cover must be maintained. Standards • Any areas that experience erosion shall be remulched and:or protected with a net or blanket. If the erosion problem is drainage related.then the problem shall be fixed and the eroded area remulched. 31 • • • Stormwater Pollution Prevention Plan Table 4.7 Mulch Standards and Guidelines Mulch Application Material Quality Standard: Rates Remarks Straw Air-dried: free from 2"-3-think; 5 Cost-effective protection when applied with adequate undesirable seed and bales per 100C sf thickness. Hand-application generally requires greater coarse material. or 2-3 tow per thickness than blown straw. The thickness of straw may be acre reduced by half when used in conjunction with seeding. In windy areas straw must be held in place by cringing,using a tackifier,or covering with netting. Blown straw always has to be held in place with a tackifier as even light winds will blow it away.Straw,however.has several deficiencies that should be considered when selecting mulch materials.It often introduces and or encourager the propagation of weed species and it has no significant long-term benefits. Straw should be used only if mulches with long-term benefits are unavailable locally. It should also not be used within the ordinary high-water elevation of surface waters(due to flotation). Hydiorralch No grow.h Approx. 25-30 S1,a1l be applied w ith htdiomukher. c1,a11 not be used inhibiting factors. is per 1000 sf without seed and tackifier unless the application rate is at of 15C0 -2000 least doubled. Fiber longer than about'..-1 arch dog Is per acre hvd<onmlch equipment. Fibers should be kept to less than inch Composted No visible water or 2 thick arm.: More effective control can be obtained by increasing Mulch and dust during approx. 10C tons thickness to 3". Excellent mulch for protecting final grades Compost run:llinP. Must be per acre(approx. turn:landscaping because it can be directly seeded or tilled purchased from 8001bs per yard) into roil.as an amendment. C.ompasted mulch has a coarser supplier with Solid size gradation than compost.It is more stable and practical Waste Handing to use in wet areas and during rainy weather conditions. Permit(unless exennx). Chipped Site Average size shall 2 minimum This is a cost-effective way to dispose of debris from Vegetation be several itches. thickness clearing and grubbing.and it eliminates the problems Gradations flora associated with bunting. Generally,it should no:be used on fines to 6 inches in slopes above approx. 10°o because of its tendency to be length for texture_ transported by runoff It is not recommended withal 2C0 variation.and feet of surface waters. If seeding is expected shortly after interlocking mulch the decomposition of the chipped vegetation may•tie properties. up nutrient important to grass establishment. Wood based No visible water or 2"thick;approx. This material is often called'hog or hogged fuel." his Mulch dust during 100 tons per acre usable as a material for Stabilized Construction Entrances hanerlinP. Must be (approx.800 lbs. (BMP C 105)and as a nnulek Tne use of mulch ultimately purchased from a per cubic yard) improves the organic matter in the soil. Special caution is supplier with a Solid advised regarding the source and composition of wood- Waste Handling based mulches. Its preparation typically does not provide Permit or one any weed seed control,so evidence of residual vegetation in exempt from solid it composition or known inclusion of weed plants or seeds waste regulations. should be monitored and prevented(or minimized). 32 1 1 ' • Stormwater Pollution Prevention Plan B M P C 209: Outlet Protection Purpose Outlet protection prevents scour at conveyance outlets and rninin,i7es the potential for downstream erosion by reducing the velocity of concentrated stormwater flows. Conditions of use Outlet protection is required at the outlets of all ponds,pipes, ditches, or other conveyances, and where runoff is conveyed to a natural or manmade drainage feature such as a stream.wetland. lake. or ditch. Design and The receiving channel at the outlet of a culvert shall be protected from Insfallntiorr erosion by rock lining a minimum of 6 feet downstream and extending up Specifrcntious the channel sides a minimum of 1—foot above the maximum tailwater elevation or 1-foot above the crown. whichever is higher. For large pipes (more than 18 inches in diameter), the outlet protection lining of the channel is lengthened to four times the diameter of the culvert. • Standard wingwalls. and tapered outlets and paved channels should also be considered when appropriate for permanent culvert outlet protection. (See WSDOT Hydraulic Manual, available through E�'SDOT Engineering Publications). • Organic or synthetic erosion blankets, with or without vegetation, are usually more effective than rock. cheaper, and easier to install. Materials can be chosen using manufacturer product specifications_ ASTM test results are available for most products and the designer can choose the correct material for the expected flow. • With low flows, vegetation(including sod)can be effective. • The following guidelines shall be used for riprap outlet protection: 1. If the discharge velocity at the outlet is less than 5 fps (pipe slope less than 1 percent), use 2-inch to 8-inch riprap. Nlinimum thickness is 1-foot. 2. For 5 to 10 fps discharge velocity at the outlet(pipe slope less than 3 percent). use 24-inch to 4-foot riprap. Minimum thickness is feet. 3. For outlets at the base of steep slope pipes (pipe slope greater than 10 percent), an engineered energy dissipater shall be used. • Filter fabric or erosion control blankets should always be used under riprap to prevent scour and channel erosion. • New pipe outfalls can provide an opportunity for low-cost fish habitat improvements. For example_ an alcove of low-velocity water can be created by constructing the pipe outfall and associated energy dissipater back from the stream edge and digging a channel, over- widened to the upstream side. from the outfall. Overwintering juvenile and migrating adult salmonids may use the alcove as shelter during 33 • Stormwater Pollution Prevention Plan BMP C220: Storm Drain Inlet Protection Purpose To prevent coarse sediment from entering drainage systems prior to permanent stabilization of the disturbed area. Conditions of Use Where storm drain inlets are to be made operational before permanent stabilization of the disturbed drainage area. Protection should be provided for all storm drain inlets downslope and within 500 feet of a disturbed or construction area, unless the runoff that enters the catch basin will be conveyed to a sediment pond or trap. Inlet protection may be used any-where to protect the drainage system It is likely that the drainage system will still require cleaning. Table 4.9 lists several options for inlet protection. All of the methods for storm drain inlet protection are prone to plugging and require a high frequency of maintenance. Drainage areas should be limited to 1 acre or less. Emergency overflows may be required where stormwater ponding would cause a hazard. If an emergency overflow is provided, additional end-of-pipe treatment may be required. Table 4.9 Storm Drain Inlet Protetion Applicable for Type of Inlet Emergency Paved!Earthen Protection Overflow Surfaces Conditions of Use Drop Inlet Protection Excavated drop inlet Yes, Earthen Applicable for heavy flows. Easy protection temporary to maintain. Large area flooding will Requirement: 3D'X 307acre occur Block and gravel drop Yes Paved or Earthen Applicable for heavy concentrated inlet protection flows. Will not pond Gravel and wire drop No Applicable for heavy concentrated inlet protection flows. Will pond. Can withstand traffic Catch basin filters Yes Paved or Earthen Frequent maintenance required. Curb Inlet Protection Curb inlet protection Small capacity Paved Used for sturdy,more compact with a wooden weir overflow installation. Block and gravel curb Yes Paved Sturdy,but limited filtration. inlet protection Culvert Inlet Protection Culvert inlet sediment 18 month expected life. trap 34 i • Stormwater Pollution Prevention Plan Design and E cavated Drop Inlet Protection -An excavated impoundment around the Installation) storm drain. Sediment settles out of the stomuwater prior to entering the Specifications storm drain. • Depth 1-2 ft as measured from the crest of the inlet structure. • Side Slopes of excavation no steeper than 2:1_ • Minimum volume of excavation 35 cubic yards. • Shape basin to fit site with longest dimension oriented toward the longest inflow area. • Install provisions for draining to prevent standing water problems. • Clear the area of all debris. • Grade the approach to the inlet uniformly. • Drill weep holes into the side of the inlet. • Protect weep holes with screen wire and washed aggregate. • Seal weep holes when removing structure and stabilising area. • It may be necessary to build a temporary dike to the down slope side of the structure to prevent bypass flow. Block and Gravel Filter-A barrier formed around the storm drain inlet with standard concrete blocks and gravel. See Figure 4.14_ • Height 1 to 2 feet above inlet. • Recess the first row 2 inches into the ground for stability. • Support subsequent courses by placing a 2x4 through the block opening. • Do not use mortar. • Lay some blocks in the bottom row on their side for dewatering the pool. • Place hardware cloth or comparable wire mesh with s-inch openings over all block openings. • Place gravel just below the top of blocks on slopes of 2:1 or flatter. • An alternative design is a gravel donut. • Inlet slope of 3:1. • Outlet slope of 2:1. • 1-foot wide level stone area between the structure and the inlet • Inlet slope stones 3 inches in diameter or larger. • Outlet slope use gravel '.. -to 3.s-inch at a minimum thickness of 1-foot. 35 MO Stormwater Pollution Prevention Plan Plan View A G•etc Da „ °. ° O• • F. s• 6.54 n. �_ cf>, 6 Concrete .. ;,o Block 4.. 40,c4 ino[ill -. A' �,.Ro54 .ti0n " i_�°eQ .r Gravel �•�!_' ttackrll 'ix..U4 4 `M1 la;44 v 1 �— C •oO 'O� • • oOk. ://: A Section A - A Concrete Block Wire Screen or Filter Fabric Gravel9acktill �p.;crdcwN. pondn9 Height Water \ 9 Pam- f.J, Water _ \ >>>..\` \ \`/,' X'' \//ice/j "\ A/ r t, Notes: 1.Drop inlet sediment barrens are to be used fcr small.nearly leve';dra nave a-eas i ess than f:.a 2.Excavate a bas n of sufcent s ze adjacent tc the drop inlet. 3 The top of the szucmre(paa3_ng beigkt',oast be we:l be:ow•the pound elevation downslope to prevent runoff from bypassing the ni.et A temporary dike may be necessary on the down ope side of the stntctu e Figure 4.14-Block and Gravel Filter Gravel and TTSre Mesh Filter-A gravel barrier placed over the top of the inlet. This structure does not provide an overflow. • Hardware cloth or comparable wire mesh with'.:-inch openings. • Coarse aggregate. • Height 1-foot or more. 18 inches wider than inlet on all sides. • Place wire mesh over the drop inlet so that the wire extends a minimum of 1-foot beyond each side of the inlet structure. • If more than one strip of mesh is necessary.overlap the strips. • Place coarse aggregate over the wire mesh. • The depth of the gravel should be at least 12 inches over the entire inlet opening and extend at least 18 inches on all sides. 36 • . Stormwater Pollution Prevention Plan BMP C233: Silt Fence Purpose Use of a silt fence reduces the transport of coarse sediment from a construction site by providing a temporary physical barrier to sediment and reducing the runoff velocities of overland flow. See Figure 4.19 for details on silt fence construction. Conditions of Use Silt fence may be used downslope of all disturbed areas_ • Silt fence is not intended to treat concentrated flows,nor is it intended to treat substantial amounts of overland flow. Any concentrated flows must be conveyed through the drainage system to a sediment pond. The only circumstance in which overland flow can be treated solely by a silt fence,rather than by a sediment pond. is when the area draining to the fence is one acre or less and flow rates are less than 0.5 cfs. • Silt fences should not be constructed in streams or used in V-shaped ditches. They are not an adequate method of silt control for anything deeper than sheet or overland flow. Jo'is in titer fabric shall be sliced at posts.Use staples.wire rings or 2'x2'try 14 Ga.wire or equvalent to attach fabric to posts equivalari. I'starxta•d strength tabnc used •'LAi:miflilLG.ipil A.Iter tab'c 1 �AI:AlL[A3[A3[A7: I C I I :mun::nHmr I I 1 •:II133l333w33'?3i WI.11I1A..A7; .:6ecr =11=11= u-r-u-n—u=a=u-..-.. —.— u=11=II=11=11 — — 't11,TII ItU II It I• it I 'UWI ,, -•' 11=M ma K 1 r'. Minimurn 4'x4'trench I Hack1111 trench wit-native sail —it^ Post spacing may be inc'eased or 3s 4"-1.5'washed gravel to 8'rt wire backing is used 2'x2'wood posts,steel fence posts,or equivalent Figure 4.19—Silt Fence Design and • Drainage area of 1 acre or less or in combination with sediment basin Installation in a larger site. Specifications • Maximum slope steepness(normal(perpendicular)to fence line) 1:1. • Maximum sheet or overland flow path length to the fence of 100 feet_ • No flows greater than 0.5 cfs. • The geotextile used shall meet the following standards. All geotextile properties listed below are minimum average roll values(i.e.,the test result for any sampled roll in a lot shall meet or exceed the values shown in Table 4.10): 37 • • ' Stormwater Pollution Prevention Plan Table 4.10 Geotextile Standards Polymeric Mesh AOS 0.60 mm maximum for slit film wovens(43C sieve). 0.3C (ASTM D4751) mm maximum for all other geotextile types(#50 sieve). 0.15 mm minimum for all fabric types(#100 sieve). Water Permittivity 0.02 sec.'minimum (ASTM D4491) Grab Tensile Suength 180 lbs.Minimum for extra strength fabric. (ASTM D4632) 100 lbs minimum for standard strength fabric. Grab Tensile Strength 3C°o maximum (ASTM D4632) Ultraviolet Resistance 70%minimum (ASTM D4355) • Standard strength fabrics shall be supported with wire mesh, chicken wire, 2-inch x 2-inch wire, safety fence, or jute mesh to increase the strength of the fabric. Silt fence materials are available that have synthetic mesh backing attached. • Filter fabric material shall contain ultraviolet ray inhibitors and stabilizers to provide a minimum of six months of expected usable construction life at a temperature range of 0°F. to 120°F. • 100 percent biodegradable silt fence is available that is strong_ long lasting, and can be left in place after the project is completed, if permitted by local regulations. • Standard Notes for construction plans and specifications follow. Refer to Figure 4.19 for standard silt fence details. The contractor shall install and maintain temporary silt fences at the locations shown in the Plans. The silt fences shall be constructed in the areas of clearing. grading, or drainage prior to starting those activities. A silt fence shall not be considered temporary if the silt fence must function beyond the life of the contract. The silt fence shall prevent soil carried by runoff water from going beneath_ through, or over the top of the silt fence. but shall allow the water to pass through the fence. The minimum height of the top of silt fence shall be 2 feet and the maximum height shall be ?1. feet above the original ground surface. The geotextile shall be sewn together at the point of manufacture. or at an approved location as determined by the Engineer, to form geotextile lengths as required. All sewn seams shall be located at a support post Alternatively, two sections of silt fence can be overlapped,provided the Contractor can demonstrate. to the satisfaction of the Engineer, that the overlap is long enough and that the adjacent fence sections are close enough together to prevent silt laden water from escaping through the fence at the overlap. 38 1 ' Stormwater Pollution Prevention Plan The geotextile shall be attached on the up-slope side of the posts and support system with staples, wire, or in accordance with the manufacturers recommendations. The geotextile shall be attached to the posts in a manner that reduces the potential for geotextile tearing at the staples, wire, or other connection device_ Silt fence back-up support for the geotextile in the form of a wire or plastic mesh is dependent on the properties of the geotextile selected for use_ If wire or plastic back-up mesh is used, the mesh shall be fastened securely to the up-slope of the posts with the geotextile being up-slope of the mesh back-up support. The geotextile at the bottom of the fence shall be buried in a trench to a minimum depth of 4 inches below the ground surface. The trench shall be backfilled and the soil tamped in place over the buried portion of the geotextile, such that no flow can pass beneath the fence and scouring can not occur. When wire or polymeric back-up support mesh is used. the wire or polymeric mesh shall extend into the trench a minimum of 3 inches. The fence posts shall be placed or driven a minimum of 18 inches. A minimum depth of 12 inches is allowed if topsoil or other soft subgrade soil is not present and a minimum depth of 18 inches cannot be reached. Fence post depths shall be increased by 6 inches if the fence is located on slopes of 3:1 or steeper and the slope is perpendicular to the fence. If required post depths cannot be obtained. the posts shall be adequately secured by bracing or guying to prevent overturning of the fence due to sediment loading. Silt fences shall be located on contour as much as possible_ except at the ends of the fence, where the fence shall be turned uphill such that the silt fence captures the runoff water and prevents water from flowing around the end of the fence. If the fence must cross contours, with the exception of the ends of the fence, gravel check dams placed perpendicular to the back of the fence shall be used to minimise concentrated flow and erosion along the back of the fence. The gravel check dams shall be approximately 1- foot deep at the back of the fence. It shall be continued perpendicular to the fence at the same elevation until the top of the check dam intercepts the ground surface behind the fence. The gravel check dams shall consist of crushed surfacing base course, gravel backfill for walls_ or shoulder ballast. The gravel check dams shall be located every 10 feet along the fence where the fence must cross contours. The slope of the fence line where contours must be crossed shall not be steeper than 3:1. Wood, steel or equivalent posts shall be used. Wood posts shall have minimum dimensions of 2 inches by 2 inches by 3 feet minimum length, and shall be free of defects such as knots, splits. or gouges. 39 • Stormwater Pollution Prevention Plan Steel posts shall consist of either size No. 6 rebar or larger. ASTM A 120 steel pipe with a minimum diameter of 1-inch, U. T. L, or C shape steel posts with a minimum weight of 1.35 lbs. ft. or other steel posts having equivalent strength and bending resistance to the post sizes listed_ The spacing of the support posts shall be a maximum of 6 feet. Fence back-up support. if used. shall consist of steel wire with a maximum mesh spacing of 2 inches, or a prefabricated polymeric mesh. The strength of the wire or polymeric mesh shall be equivalent to or greater than 180 lbs. grab tensile strength. The polymeric mesh must be as resistant to ultraviolet radiation as the geotextile it supports. • Silt fence installation using the slicing method specification details follow. Refer to Figure 4.20 for slicing method details_ The base of both end posts must be at least 2 to 4 inches above the top of the silt fence fabric on the middle posts for ditch checks to drain properly. Use a hand level or string level, if necessary, to mark base points before installation. Install posts 3 to 4 feet apart in critical retention areas and 6 to 7 feet apart in standard applications. Install posts 24 inches deep on the downstream side of the silt fence, and as close as possible to the fabric, enabling posts to support the fabric from upstream water pressure. Install posts with the nipples facing away from the silt fence fabric. Attach the fabric to each post with three ties, all spaced within the top 8 inches of the fabric. Attach each tie diagonally 45 degrees through the fabric, with each puncture at least 1 inch vertically apart. In addition_ each tie should be positioned to hang on a post nipple when tightening to prevent sagging. Wrap approximately 6 inches of fabric around the end posts and secure with 3 ties. No more than 24 inches of a 36-inch fabric is allowed above ground level. The rope lock system must be used in all ditch check applications. The installation should be checked and corrected for any deviation before compaction. Use a flat-bladed shovel to tuck fabric deeper into the ground if necessary_ Compaction is vitally important for effective results. Compact the soil immediately next to the silt fence fabric with the front wheel of the tractor, skid steer. or roller exerting at least 60 pounds per square inch. Compact the upstream side first and then each side twice for a total of four trips_ 40 Stormwater Pollution Prevention Plan • Any damage shalt be repaired immediately. Maintenance • If concentrated flows are evident uphill of the fence,they must be Standards intercepted and conveyed to a sediment pond. • It is important to check the uphill side of the fence for signs of the fence clogging and acting as a bather to flow and then causing channelization of flows parallel to the fence. If this occurs.replace the fence or remove the trapped sediment. • Sediment deposits shall either be removed when the deposit reaches approximately one-third the height of the silt fence, or a second silt fence shall be installed. • If the filter fabric(geotextile)has deteriorated due to ultraviolet breakdown it shall be replaced. p.m..mdom POST SPAOM/0: weal,e4 'Sr,wow•r woo now 4 4'max.oil.poolow.roar to _ . a Mama I 4c r �11. ` lase Maa urrr.w rr.r if out ; , \ lt r ill PUP NV o w...w..rr.w r POST Dt P TN: MI Mlr.r IN U A. a Ww Mww• I with•wac..mat4a a.sobs.r.N Trwwr .e r.wi p a+ ..lsi I sm..r'.. 110a1. Y. O•pDIM aYlnl..rU 3 oats.row j`y/,,f` )\\`,,\`� N� .n.c race \\ \ \\\,�\ •G.h.r Lone a Doss.sands /' i.. f \� \\�' �h •rl .sea•.saps pea a..n�M no e-af ab& li,i\/%fir` • \4.j'').4 •Paiimm'sets IS•hrinaan d Y a�n P�•sG hair wllle.y • 1100116 and No mom than 24"of a 3r fubdc a .r Osaa i room y or Kg vac s allowed above ground. Rol of set hence 4same opp►etbn I 'ON aAel eon 111111111 i NOW cornpac t-• . of,wows swrar e ,AIL' *_. 1 1/,/! �� ( 4 a .. r: ,, wD . ! p", J .'f44 i?.' ;'Y' $y:i.$4:*. '',.4.4 9$ , •ti.4'<' 4'''''y ermenMe WNW point S king bl60• Mt town mien) ne gone eldsil com plaIed e.lellaron Vibratory prow it not acceptable because Of hoetoteal compaction Figure 4.20 -Silt Fence Installation by Slicing Method 41 • Stormwater Pollution Prevention Plan BMP C235: Straw Wattles Purpose Straw wattles are temporary erosion and sediment control barriers consisting of straw that is wrapped in biodegradable tubular plastic or similar encasing material. They reduce the velocity and can spread the flow of rill and sheet runoff,and can capture and retain sediment. Straw wattles are typically 8 to 10 inches in diameter and 25 to 30 feet in length. The wattles are placed in shallow trenches and staked along the contour of disturbed or newly constructed slopes. See Figure 4.21 for typical constriction details. Conditions of Use • Disturbed areas that require immediate erosion protection. • Exposed soils during the period of short construction delays, or over winter months. • On slopes requiring stabilization until permanent vegetation can be established. • Straw wattles are effective for one to two seasons. • If conditions are appropriate, wattles can be staked to the ground using willow cuttings for added revegetation. • Rilling can occur beneath wattles if not properly entrenched and water can pass between wattles if not tightly abutted together. Design Criteria • It is critical that wattles are installed perpendicular to the flow direction and parallel to the slope contour. • Narrow trenches should be dug across the slope on contour to a depth of 3 to 5 inches on clay soils and soils with gradual slopes_ On loose soils, steep slopes. and areas with high rainfall. the trenches should be dug to a depth of 5 to 7 inches. or 112 to 2.3 of the thickness of the wattle. • Start building trenches and installing wattles from the base of the slope and work up. Excavated material should be spread evenly along the uphill slope and compacted using hand tamping or other methods. • Construct trenches at contour intervals of 3 to 30 feet apart dependunw on the steepness of the slope, soil type, and rainfall. The steeper the slope the closer together the trenches. • Install the wattles snugly into the trenches and abut tightly end to end. Do not overlap the ends. • Install stakes at each end of the wattle, and at 4-foot centers along entire length of wattle. • If required, install pilot holes for the stakes using a straight bar to drive holes through the wattle and into the soil_ • At a minimum wooden stakes should be approximately 314 x 3.4 x 24 inches. Willow cuttings or 3/8-inch rebar can also be used for stakes. 42 • fl Y Stormwater Pollution Prevention Plan Maintenance • Stakes should be driven through the middle of the wattle,leaving 2 to 3 Standards inches of the stake protruding above the wattle. • Wattles may require maintenance to ensure they are in contact with soil and thoroughly entrenched, especially after significant rainfall on steep sandy soils. • Inspect the slope after significant stones and repair any areas where wattles are not tightly abutted or water has scoured beneath the wattles. 3-$ I = (1,2m) \ \, ., 2,..., -.. /\41,- . s., Straw Rolls Must '` '�I� .� `', i Be Placed Along ♦ \�r,. `: Slope Contours '4` ' �;-:' Ilk' ` Adjacent rolls shell /1 \ \ tig tk a5ut - 4 ,,,,, 10'•25'l3•Rm., �` I... / Spacing Depends on Soil Ty pe and -/ � Sedin►efd,organic wrier, Slope Steepness 4k.. and native sags are may\ :aFtured Ward the rolls. wi~ Sri 3'4'(?'S•125m1 en: <�� 0%10"DIA, \+ r , 1 (4t)(t•250mrnl mar Live Stake k 4. i �Y �I^ 1" X1" Stake �, not to scale (25 x 25rrmi 1 NOTE. 1.Straw roll ms:allattan regimes the placement and secure staking ol'the roU in a trench,3"4•(75-125msn) deep,dug on contour runoff must oM be allowed to run under or around roll 43 • , Stormwater Pollution Prevention Plan Appendix C —Alternative BMPs a list of possible alternative BMPs for elements 1-10 not described in the The following includes 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. All BMPs can be found in Volume 2 of the 2005 Stormwater Pollution Prevention Manual, pages 53-169. Element#1 - Mark Clearing Limits • Stake and Wire Fence( BMP C 104) Element#2 - Establish Construction Access • Wheel Wash( BMP C106) Element#3 - Control Flow Rates • Infiltration Trench Element#4 - Install Sediment Controls • Construction Stormwater Filtration( BMP C251) Element#5 - Stabilize Soils • Nets and Blankets( BMP C122) Element#6- Protect Slopes • Surface Drains( BMP C 205) Element#7— Protect Drain Inlets • Excavated Drop Inlet Protection Element#8 - Stabilize Channels and Outlets • Channel Lining( BMP C 202) • Check Dams ( BMP C 207) Element#10 - Control Dewatering • Construction Stormwater Filtration( BMP C251) 44 Stormwater Pollution Prevention Plan Appendix D — General Permit Not Required for this project 45 • • 4 1 1 r 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, approximate amount of precipitation since the last inspection, and approximate 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 v. locations where additional or different BMPs are needed, and the reason(s) why e. A description of stormwater 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 BMP repairs,maintenance or installations made as a result of the inspection. h. A statement that, in the judgment of the person conducting the site inspection, the site is either in compliance or out of compliance with the terms and conditions of the SWPPP. If the site inspection indicates that the site is out of compliance, the inspection report shall include a summary of the remedial actions required to bring the site back into compliance, as well as a schedule of implementation. 46 • Stormwater Pollution Prevention Plan Name, title, and signature of person conducting the site inspection; and the following statement: "I certify under penalty of law that this report is true, accurate, and complete, to the best of my knowledge and belief'. 47 • • Stormwater Pollution Prevention Plan Site Inspection Form General Information Project Name: Inspector Name: Title: CESCL # : Date: Time: Inspection Type: o After a rain event o Weekly o Turbidity/transparency benchmark exceedance o Other Weather Precipitation Since last inspection In last 24 hours Description of General Site Conditions: Inspection of BMPs Element 1: Mark Clearing 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 Element 2: Establish Construction Access BMP: Location Inspected Functioning Problem/Corrective Action YN Y N NIP 48 Stormwater Pollution Prevention Plan BMP: Location Inspected Functioning Problem/Corrective Action Y N Y N NIP Element 3: Control Flow Rates 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 4: Install Sediment Controls 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 BMP: Location Inspected Functioning Problem/Corrective Action Y N Y N NIP 49 • Stormwater Pollution Prevention Plan Element 5: Stabilize Soils 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 BMP: Location Inspected Functioning Problem/Corrective Action Y N Y N NIP Element 6: Protect Slopes 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 50 i Stormwater Pollution Prevention Plan Element 7: Protect Drain Inlets 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 8: Stabilize Channels and Outlets 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 BMP: Location Inspected Functioning Problem/Corrective Action Y N Y N NIP 51 i i Stormwater Pollution Prevention Plan Element 9: Control Pollutants 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 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 52 • 41) Stormwater Pollution Prevention Plan Stormwater Discharges From the Site Observed? Problem/Corrective Action Y N Location Turbidity Discoloration Sheen Location Turbidity Discoloration Sheen Water Quality Monitoring Was any water quality monitoring conducted? o Yes o No If water quality monitoring was conducted, record results here: If water quality monitoring indicated turbidity 250 NTU or greater; or transparency 6 cm or less, was Ecology notified by phone within 24 hrs? ❑ Yes o 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 repairs, maintenance, or installations made as a result of the inspection. Were Photos Taken? o Yes ❑ No If photos taken, describe photos below: 53 • Stormwater Pollution Prevention Plan Runoff Control Devices Infiltration Trench Sizing per Volume III, Section 3.1.1 of the Stormwater Management Manual for Western Washington, (DOE, 2005) A 4' x 4' x 47' infiltration trench shall be constructed to infiltrate the runoff from the roof area of the proposed house. Driveway Flow Dispersion per guidelines of BMP T5.11 of Volume 5 of the Stormwater Management Manual for Western Washington, (DOE, 2005) The runoff from the driveway shall be directed to the undisturbed natural vegetation to the North. There is adequate natural vegetation to infiltrate the runoff. f t• ■ J' t • • writ_TRATI6r\) - nENL(-{ Sf ZE F0 R Hoy S E t25 x 2 x 1,5 ' F'CR 1000 sr OF ROOF ARQA CF PEE ( 000 sF 0F ,C00F 14cr3 SF OF ROOF 1, 4`13 '' 37S Y 7 :115 CF 0P-re.s&C(' �-/ X 4 � TREc1G!-I 7447, 1-75 CF_ LJ . 7 LF OF 77eENLtj /G USC `-1 ' x y x y n� rLT-2A7 v ) EAJ61-1 � . Western Washington ology Model PROJECT PORT Project Name: 08050 trench Site Address: City Report Date : 6/3/2008 Gage Quilcene Data Start 1948/10/01 Data End 1993/09/30 Precip Scale: 1.11 PREDEVELOPED LAND USE Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres C, Forest, Steep 2.07 Impervious Land Use Acres Element Flows To: Surface Interflow Groundwater Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres C, Forest, Steep 1.931 Impervious Land Use Acres Element Flows To: Surface Interflow Groundwater MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.276281 5 year 0.401772 10 year 0.498781 25 year 0.638319 50 year 0.755327 100 year 0.884169 4 i d 4 ! III 411 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.257729 5 year 0.374793 10 year 0.465288 25 year 0.595456 50 year 0.704607 100 year 0.824799 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0. 691 0. 645 1951 0.245 0.228 1952 0.325 0.303 1953 0.236 0.221 1954 0.306 0.285 1955 0.363 0.339 1956 0.362 0.338 1957 1.225 1.143 1958 0.274 0.255 1959 0.333 0.310 1960 0.483 0.450 1961 0.327 0.305 1962 0.335 0.313 1963 0.293 0.273 1964 0.272 0.254 1965 0.215 0.201 1966 0. 132 0. 123 1967 0. 660 0. 616 1968 0.323 0.301 1969 0.272 0.254 1970 0.248 0.232 1971 0.287 0.268 1972 0.374 0.349 1973 0.323 0.302 1974 0.296 0.276 1975 0.369 0.344 1976 0.270 0.252 1977 0.338 0.316 1978 0.213 0.198 1979 0.233 0.218 1980 0.281 0.262 1981 0.237 0.221 1982 0.205 0. 192 1983 0.206 0. 193 1984 0.475 0.443 1985 0.135 0.126 1986 0.174 0.162 1987 0.282 0.263 1988 0.252 0.235 1989 0.214 0. 199 1990 0.127 0. 118 1991 0. 155 0.145 1992 0.327 0.305 1993 0.322 0.300 1994 0.204 0. 190 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 1.2254 1. 1431 2 0. 6913 0. 6449 3 0. 6600 0. 6157 4 0. 4826 0.4502 5 0.4748 0.4429 6 0.3736 0.3485 7 0.3693 0.3445 8 0.3632 0.3388 *` .` 0.3625 3382 . 10 0.3382 .3155 11 0.3354 0.3129 12 0.3326 0.3102 13 0.3271 0.3051 14 0.3266 0.3047 15 0.3252 0.3034 16 0.3234 0.3017 17 0.3230 0.3013 18 0.3216 0.3000 19 0.3055 0.2850 20 0.2961 0.2762 21 0.2928 0.2731 22 0.2871 0.2678 23 0.2825 0.2635 24 0.2808 0.2619 25 0.2738 0.2554 26 0.2725 0.2542 27 0.2718 0.2535 28 0.2697 0.2516 29 0.2522 0.2352 30 0.2482 0.2315 31 0.2445 0.2281 32 0.2372 0.2213 33 0.2365 0.2206 34 0.2333 0.2176 35 0.2154 0.2010 36 0.2136 0.1993 37 0.2127 0.1984 38 0.2064 0.1925 39 0.2053 0.1915 40 0.2035 0.1899 41 0. 1742 0.1625 42 0.1550 0.1446 43 0.1349 0. 1258 44 0.1323 0.1234 45 0.1267 0.1182 POC #1 The Facility PASSED The Facility PASSED. Flow(CFS) Predev Dev Percentage Pass/Fail 0.1381 2988 2512 84 Pass 0.1444 2685 2242 83 Pass 0.1506 2419 2001 82 Pass 0.1568 2182 1781 81 Pass 0.1631 1929 1531 79 Pass 0.1693 1714 1354 78 Pass 0.1755 1527 1195 78 Pass 0.1818 1359 1057 77 Pass 0.1880 1188 915 77 Pass 0.1942 1060 815 76 Pass 0.2005 950 698 73 Pass 0.2067 840 604 71 Pass li 0.2130 736 524 71 Pass 0.2192 632 442 69 Pass 0.2254 552 379 68 Pass 0.2317 487 326 66 Pass 0.2379 418 280 66 Pass 0.2441 355 235 66 Pass 0.2504 312 202 64 Pass 0.2566 270 161 59 Pass 0.2628 232 143 61 Pass 0.2691 195 119 61 Pass 0.2753 157 108 68 Pass 0.2815 141 90 63 Pass 0.2878 123 84 68 Pass L 47*. '002 95 58 61410 PassIII ' 0.3065 86 44 51 Pass 0.3127 74 38 51 Pass 0.3189 64 32 50 Pass 0.3252 50 30 60 Pass 0.3314 44 25 56 Pass 0.3376 35 25 71 Pass 0.3439 32 22 68 Pass 0.3501 28 19 67 Pass 0.3563 25 19 76 Pass 0.3626 25 16 64 Pass 0.3688 22 14 63 Pass 0.3750 19 12 63 Pass 0.3813 19 12 63 Pass 0.3875 17 12 70 Pass 0.3937 14 11 78 Pass 0.4000 13 11 84 Pass 0.4062 12 8 66 Pass 0.4124 12 6 50 Pass 0.4187 12 6 50 Pass 0.4249 11 6 54 Pass 0.4311 9 6 66 Pass 0.4374 7 5 71 Pass 0.4436 6 4 66 Pass 0.4499 6 4 66 Pass 0.4561 6 3 50 Pass 0.4623 6 3 50 Pass 0.4686 5 3 60 Pass 0.4748 5 3 60 Pass 0.4810 4 3 75 Pass 0.4873 3 3 100 Pass 0.4935 3 3 100 Pass 0.4997 3 3 100 Pass 0.5060 3 3 100 Pass 0.5122 3 3 100 Pass 0.5184 3 3 100 Pass 0.5247 3 3 100 Pass 0.5309 3 3 100 Pass 0.5371 3 3 100 Pass 0.5434 3 3 100 Pass 0.5496 3 3 100 Pass 0.5558 3 3 100 Pass 0.5621 3 3 100 Pass 0.5683 3 3 100 Pass 0.5745 3 3 100 Pass 0.5808 3 3 100 Pass 0.5870 3 3 100 Pass 0.5932 3 3 100 Pass 0.5995 3 3 100 Pass 0.6057 3 3 100 Pass 0. 6119 3 3 100 Pass 0. 6182 3 2 66 Pass 0.6244 3 2 66 Pass 0. 6306 3 2 66 Pass 0.6369 3 2 66 Pass 0.6431 3 2 66 Pass 0. 6493 3 1 33 Pass 0.6556 3 1 33 Pass 0.6618 2 1 50 Pass 0.6680 2 1 50 Pass 0.6743 2 1 50 Pass 0.6805 2 1 50 Pass 0.6868 2 1 50 Pass 0.6930 1 1 100 Pass 0. 6992 1 1 100 Pass 0.7055 1 1 100 Pass 0.7117 1 1 100 Pass 0.7179 1 1 100 Pass 0.7242 1 1 100 Pass 0.7304 1 1 100 Pass n '7ZFti 1 1 inn Dmco F E-4114. / 29 1 1 100 Pass 0.7491 1 1 100� Pass • 0.7553 1 1 100 Pass Water Quality BMP Flow and Volume for POC 1. On-line facility volume: 0 acre-feet On-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. Off-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. This program and accompanying documentation is provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions and the Washington State Department of Ecology disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions and/or the Washington State Department of Ecology be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions or the Washington State Department of Ecology has been advised of the possibility of such damages. ff Ili! g /III gggg g gg 1i Ø !l. tit!f l n Y 1 o 1A as ease ease@BEaa as Nit - e .Q eR �e '� �aFaF1„_. m li u_ U 18 >� " - o Rl al el ml x° AI" el" la 7° ° 8 Si€ O S9 3 9m Q Egz11,1 $am " a F 4o z y y� W y$ c�ZZ P ¢n33� ygygaa _ m� gn 7 � L7 m s d a g e II l Q OS °.,st1,1 00 0.2m0$ _ ° E s 8 = g I y �3 p 99 0 99 `d 99 1 y 4 i F - i �r 'Shy 02. EKW1�01. 3,0.- _ i9 `S Ili IIIUIIIIIII p E8N vilig= gsm $ qpu a m Spp�ySyS��e igI¢ Iblil WO J 6i 539€ Y�i s f11EEE1iis g II s gAg g" - tr I�y� pp LI. ° CCC L1 o r� YIgy §WO § ! 1 w E01 1 C 4 11 4 cc 8 O o n ,, i .� 5 ds H6 < < 0 Le 0 Ce '� o $ ' fip O grci " O fq s 11 Lg 41 g ° R �� 0 F 0 to y li mh i F. LLP '7aP aPN ; i li ; r p ° ili'to ..- to E t tl 12 " 1 1 2'2 g i 00 0 o r a r r g 0 P Z$ .2181 I #Y OO wm u Nwi Ls Q ," 9r -4 RgW a V ron n n z8 ' O 1-4E i/n E-�ddEN-it° 'i < __I d 0)6 g � E' a 3" L.�o :gg d eg '� « & }� � pp p n m e s 5 W g . a{a{" �k owi g 6 ;6 l Q 1 0 v Uo m O I Bi n O w ri o o O it cal E m 0 w m z vD wi ix - w O o m en w CD X~ 2 N S~0 .., w in W CC o O �- J0 2 I- a-'� L. J U) ! n ' ___.1 QW N =U' a Q a I _ W 00 �' � ' C m oz Z Ca Z • m � � LL m __Ia _-_a I- ce O ao c .B/L ra 1 Ale Pz I LI C-S 1.Y/01-z 1 AC 8-.s lac O z 1 2/1.vs1 AC►Z I AnhL / W E xli�1.-r in 1--\ I y ZL VACJ 4 \ 4 19 ao I(o)1no-o wioI) N (seo iroso© ¢ 0,,....:, N, -eeo N 7 N, N ^ N I en IM If��7i,'er.I gg111,1\ �6'n��IL�ll�i-1►Ls (eA s A-A .Lll o-1I !! J 1►� . F I _it I. Z wl-� L JQL!!..tk DiilJlix � / e t� a Lll In �� Js s g 4 Y¢" © $4 8Ler1e.B000010LL / • y- —} _ I-N t E - • I (8C m Nil Ill 1 l.1N.!1. 1 - • lly 3 4. - 7, , .N " I1 a a ®• _4"o S II L111 1 i61 0 g J. I'Vk 'v' ' I - ' "-.;I,II II iJLrSL �� � III —4- ° QkN —mo; k O oW• ? " SN30NV /M180f 3 , I .L-.LIId P a � z r,L r81 e o / n„ 66 O • El' / •4I I aA —�N O �� 4C 1y� � I ZL B-,H ONRatle:..lo no Moo 1 1? q ,,, k 'O°AO istoraoadalxz b was :01, '% O �_ 2/s-zL CG � I naY h ---1 . � IIILI IT O L2 1 ,; k'6 \ II, R LWmxuI 7Z Ifl.b/ NI 1S \-i MN . L/L 0-.r / flICPCy hy I, k P(-1-_-11 Ny 4Ia id Sig - J F4 Oab O _ Ny4 J•1\ l K 1 - i %* i I . Z , 3 S_ 0 LL § l_ O yW ^ I�.TJms�L,m LC zit2/Ls t. W -I • rlcj c N i yy iKZ0 'Val* © (0lC1O F- I;., gE 'ow to III 8 r b �a kg 1 11 feg i A•A0 / 2JLY,Y ' .n6 /AL/CL o-t/ARB-z" A141 We "XI01-z' .MI OVAL .0-.1, ' A-ze I- Y N f 4 P 4 4 4 W ; 4 ; 4 ; 4 N '� g g yj! 4 t 1p i q�q (t pt t• t [�iy u� lihili E il ii gSBa � E'°Ep q ik � _s 6„P t4 g 7 q 9 9 ` 9 9 tp IIIb i E 2 g k11tH : d y19 W Q, I! i a Sg . w =3 py 1.2- 81 g§e9"g--- • Q -K �u ° C �u OZ �u a 8� p 4 j W 2 z a l •N p LL $ 8 z 2 31 X i- €f i l.:1£m u a 0 o§ $ � 5 & lig ° tAggilS l ' o a s - RLL Z 2111=`E i� ��..81 ,i F;w. 0 4 u u u z o t , A ° ; 2 n n m cWi W tIy. 1 r� „s E �4 e" p° < < < .1 m N N ii £E m •T3 O Oy: 4Eg PE 3` s ° ob' oo > _ 11§c q 8q zozu $ $ $ $ QQ $ $ $ m 8d < N3 �` .: $ annnnr � � ?.qillfr1s yslzitiEG�W°- N . ., Y !O Tc 2 i � J F7 ill" im�'c'E u= 8B � � C1 1 1.0 o fl54AL O r i I C-) g 5 °�4 W cJ ° R a !g 6 CD Y \ I-- r- 4 0 in J I \ \ AL.,," . ..•� a) ? r f h , U oi 4 ^F it . .:,O 4 8O Agillik N N '1y J Itrifariali I oy 1 All L-.11 \ .01 oW 0 1 ;!i Q/� � °o m U)a \ Y § ...unini ,„, Oi I \ to CC 0 a 7§ °° :g 0SI w 0 A 0 —g Qss .wi o-.0 _ 0 .v1 o-s1 Q z AIX Si, .9451 L-.s1 N A N h 111I aX eh J� g '` Nfn C � en w _ Z § a ow O 's » UN . w l N 4 0 0 L J 0 g, ` NIW A Qw \ A_____ m •kz' • GI O .o-.lr / L.0 .i .fin 0-.I u\ a ° k k • m m a w 1 a $ ^q k k ��.ms .vie-s1 .m ran ` ttms \ P \ LOOK Idol do 3003 \ I gE a � o t3 a �m �N d ,— k �: m k .7 Li b 4 U H 1 4 T 2 \ I�zwe 1 '-+—o---- . k \ +v N Q R e.� ®® : ` IOZW9I 0 l h8'zn o SMO.o 1 r.1 < o _� Na k Iiiir----- d M' 2 8 b; �o \ �\ \ ` \ / m\ \ ` i « 11OO1i 14O1dO 3003 n ` ` L Z S k O O a $ 1 1 § LL , i Kr X ;-. a w § , AlI �j .0..LC i u / .l-,L .. w „8/9 ti-,Ol cc oa co m 0 C.. IY O CO C1 0 O F- O Q O cp , ,_: d ...— •-- __---.,) '..,'--:i 1 f�,� 1 All /11 .� N co AVE/lir 6",6 LO J CC `� , io o q . —Ill c\I ,t//0-,/ D =- cn z c. 411) „ , ,.... .. , , N. „9l/l l E 8/9 0-,Zl o „Z/l L/ / {i „8/5 Z-,9l ... \ 1,--144 \ \ lir-g4 NwsiwycAL/"N'Akw4I''. , '''''''' #1:IMAN \ my • 4 fat : wit at `° �'.1 ---7). -11r—'. i A.. — zn sk- al 17 8/9 8-• ,9 .01. 8-,L iv co `_ ® 0 !� y / ,- L w � „9l/6 Z-,O l "' !�—/ n9-,8 w 1:2 bto - ^ oZ , YI--- Z4 �, c4@p i - 000 ��ZZti I-- m rp LO / 44 0 PP O A \ W � ,'I p w -� `4 I ;I Q. � 1 co Q N ��� ,;(� ,- }._. \ \ x LU lg gLLec O p a — 0 0,8 dN d . s.a � E O � NW '• 0� /t-- CO N 0— .0-,o =6 ( J O „O1.LL W •v� „9 /6 8-,S l Q Z D -O i O- Z co o 00 2 LI- OIli >o r' J N2.1 a CV m r+r. at .8/9 Z-,9 l 01 iv .O L \ it d` Q6 M� H J CV V" r r `° to _i m w o M Z II O 4,1 L11 ` o O (-_,2 _ r U inU) Q ' w U) _,,. _ in 0voa 'NM w H Y n !r „0-,Z = a 0cc LL o alf.0 R la it 8Lu e ! 1- co 5ib- x nriea f Y °j. #f , , a 'tt....... .if �i# ��y � 1��i C 1 e ti 12/4 nl '�C t .M1 i S,� '�fs,':' .. �,. ,,,61,,, ' y p M", .,,,„,! �� r , J}r terr „" r` ', Ndu,,,,, �F: S,R+Y ,�. '3ra • 131f31/101432001A0N32 '1IV113 431V210d2I03N1 SfOL6 HO '003MS0 3 HV7 '4 „lso-t>. (o9r xve �'.�IOSO—Ltti (09C) :3NONd S3iVIDOSS� 300141 21d MS lLZ£ toQ •- ,.6�1 ,� 'Q1,Z9C96 VM S3130NY 1210d DI10 �3 $In07 V2830 $ HLtdJ t13114S 'IS N19 1S113 IOC :1N3110 p °3 ? _.-_S Gv>tN ml N.I, O R N cam, �- nW J � II \ O 2 0 `b.,41:1 2 � M W`6°wVld 1011 1\10D NOISO1I3 (INV HaLVWI 1110LS oto ci- � ., c ►- h _' Z w< w w l IOIOZIOL ON 73321Vd - SIfO7 V21830 '2 H1 dV0 SOd NV J7d 311S :3 u co o E —. U A CD r • co �. �;*410 Q o t�_ r ti_w AEI F': '14441--------1:91:1- cd) W -III Z ?T. i z o — J F mII a0 JF o 3 O� • a aWaL� 2I cn p0. WWWW pOwdrS-�. m 304 w lQ cc NJ d < w mrT.., waaawxa §(7)a a lb o Cr) I II !�h, a 11 1 Wei/ 1 rt \ w • I I I • '��''ei OP 446/4 m I I I ,, .,. o I co I 114 I W °O7s4104 aol�� le 0I I Jhj1f J w • • ?!a! lots III 11111 11111 7---,,,„ _„„„ 1 ... � _ „„,,II,II ,� I, III ( � �F 3ne'O�— z�W=H `3N97'`s) N{J�.1 O w J y U Q' `Jo 4,0, W 3 p N U<U LI, W m 3,„ wX ZZ F <p En X 41 LA Naw 3S3H'3�yS a.Ov doN�wrn \ ?mp - ao <<orn �J I 0F61 / f 1 `t`.q • ,-(--) ,_,------ I , • 44 \.�.J� 1 ZO�QWZ I �- ,\ 1.w\ • ypW� �' X O. < • N • I / // '/�\ 'tzF O I �� it x p • • O = •• w w o x Ec°mp0�� " 2 a i• .I tr zE2U I �- x <0 `:• . . Za00F3w p a U< •A►.r; .•' �%5 FO I r--_- -.-------- .— 1.1 n K !�" 1- F I-z _f `' ...mom d �� UOeU0 I �� + ?,.;„it„.. ;, , O O C9 U .. • p yI U O dr.«.:„mid. b,.. 1'rr N"rctv''le y �}�tal • yyd._}.�rs.�S':!!.Y., X 3 0_ ] ✓ �' Ybr�, Yi'rsFryfa<'IS°Ir �� r 'S aFk:47-Yr idrra'dr�.i � XV)< / 1/4 • • '6,'!- I <z w V1 p< 1 O U ' I a T;r ,,ayy, €Y�✓ 1� .�+t , h7 a w eto, v t� i t, o- 4 w W Cr r "C� �{i y` �+rrM F P Y 1'l, r t d' �3 ti 4, S i 5i N R Q. J ! .fs' "� of r J,if ^F4 !a E! �F r7 : w. 1 fr' e ill 0< y�y�J V a, r� +n, , +{ i'+ ) 4M1Mt'" {SJ . `',r'` "t_>15r° F b o-1P''r'f1 f' t+✓'S 1 .. '3 'l 4 'try � Nlt" " "L�iy t. 4 1 t6 cd A* 1, } '�}'�"[, { 1' 1 Y}'` 6 t r :4, V-A- rr...k . 1 5.. t 'Ta fir S r•�1.." .;;Tw'Q� d? _ �r ,� W I r f .��,N P. ,, x.{' )i t ! tI 4 � r r�„`44'k?t, y� 4ry y a. \ 7. o "'1yr t• j q I a Y4 tk r v y• r C •S..I �, �+ CC fit/ p< • e {, �; f I Ays,; w Y F k -1111 / < iv 2 Cr Oq — ptr J I „ Z IrL O� ��- il � � _ _�� 1 l ---1 . ,Ao _ — J � 7 tea} I h I OH 37') \ '� / OJ W °"M.... , /,1 ,,,Ft. .d.\ T y S `y'�?�',""' �'r m r wc, 3!Y a AC Z I , Y } t +Pk r' x ir't"5,#ft 4!W�'�4 u z 001E « tK lve Lai a w W‹z t �� ", �����.dds` w —1 N p W 1 aApa +�,w�r;k.ri ix ZI w^ I:Y �µ rro✓�cwi rtw1 P.w., r EL z T�y !1y a . ., • . <0f= ( I. �� ,'gip ,_ �3 1 L / t. Zp w p U 1; I y='> odoa a3dld )yu .2 II ': I..Ls IOW