Document Redmond_doc_3edd24110f

i All Wood Recycling STORM DRAINAGE REPORT Project Location: 8504 192nd Avenue NE Redmond, Washington 98052 Prepared For: All Wood Recycling 8504 192nd Avenue NE Redmond, Washington 98052 (206) 682-5735 Prepared By: Andrew Reaves, P.E. Site Development Associates 1724 West Marine View Dr. , Ste 140 Everett, WA 98201 (425) 486-6533 Date: February 27, 2013 (revised May 8, 2013) Project Number: 102-009-10 ---PAGE BREAK--- ii All Wood Recycling Storm Drainage Report Project Location: 8504 192nd Avenue NE Redmond, Washington 98052 Prepared For: All Wood Recycling 8504 192nd Avenue NE Redmond, Washington 98052 (206) 682-5735 Prepared By: Site Development Associates 1724 West Marine View Dr., Ste. 140 Everett, WA 98201 (425) 486-6533 Date: February 27, 2013 (Revised May 8, 2013) Project Number: 102-009-10 ---PAGE BREAK--- iii TABLE OF CONTENTS SECTION 1 – EXECUTIVE SUMMARY  Project Overview SECTION 2 – MINIMUM REQUIREMENT PREPARATION OF STORMWATER SITE PLANS  Step 1: Collect and analyze information on Existing Conditions  Step 2: Prepare Preliminary Development Layout  Step 3: Perform Off-Site (Upstream and Analysis Analysis Discussion Upstream Analysis Discussion  Step 4: Determine applicable Minimum Requirements  Step 5: Prepare a Permanent Stormwater Control Plan  Step 6: Prepare a stormwater Pollution Prevention Plan (SWPP)  Step 7: Complete the Stormwater Site Plan o Conveyance System Design Calculations SECTION 3 – MINIMUM REQUIREMENT CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN – OBJECTIVES AND APPLICABILITY  Element 1: Mark Clearing Limits  Element 2: Establish Construction Access  Element 3: Control Flow Rates  Element 4: Install Sediment controls  Element 5: Stabilize Soils  Element 6: Protect Slopes  Element 7: Protect Drain Inlets  Element 8: Stabilize Channels and Outlets  Element 9: Control Pollutants  Element 10: Control De-Watering  Element 11: Maintain BMPs  Element 12: Manage The Project SECTION 4 – MINIMUM REQUIREMENT CONTROL SOURCE POLLUTION  Source Control Narrative, Strategies  Appendix 4-A – Source Control BMPs  Appendix 4-B – Spill Control Plan SECTION 5 – MINIMUM REQUIREMENT PRESERVATION OF NATURAL DRAINAGE SYSTEMS AND OUTFALLS  Natural Drainage Course Description  Offsite Mitigation Requirements SECTION 6 – MINIMUM REQUIREMENT ON-SITE STORMWATER MANAGEMENT  Hydrological Description of On-Site Drainage Patterns  Feasibility of Infiltration  Feasibility of Dispersion ---PAGE BREAK--- iv SECTION 7 – MINIMUM REQUIREMENT RUNOFF TREATMENT  Discussion of Water Quality Treatment Design SECTION 8 – MINIMUM REQUIREMENT FLOW CONTROL  Existing Site Hydrology Synopsis  Developed Site Hydrology Synopsis  Flow Control Performance Standards  Existing Drainage Basin Exhibit  Proposed South Drainage Basin Exhibit  Proposed North Drainage Basin Exhibit  Appendix 8-A – WWHM3 Flow Control Design Calculations  Appendix 8-B – Pump Design Calculations SECTION 9 – MINIMUM REQUIREMENT WETLANDS PROTECTION SECTION 10 – MINIMUM REQUIREMENT BASIN/WATERSHED PLANNING SECTION 11 – MINIMUM REQUIREMENT #10: OPERATION AND MAINTENANCE SECTION 12 – SPECIAL REPORTS AND STUDIES  Appendix 12-A – Geotechnical Report ---PAGE BREAK--- v SECTION 1 EXECUTIVE SUMMARY ---PAGE BREAK--- vi PROJECT OVERVIEW All Wood Recycling is a wood, concrete and asphalt recycling company occupying 4.77 acres in eastern Redmond. It is an existing use and company that has been operating on the property for approximately 18 years. This report is an analysis of the existing drainage system. The site lies in the SE ¼ of Section 6, Township 25North, Range 6 East, W.M. More specifically, the project lies at 8504 192nd Avenue, NE, Redmond Washington. A vicinity map has been provided as Figure 1 of this document. The project site occupies City of Redmond County, Tax Lot #[PHONE REDACTED]. The site is covered in impervious surface, with Evans Creek bisecting the site, flowing from the SE to the NW. The topography of the site can generally be described as flat as it is on a plateau of structural fill to the north of Evans Creek placed some decades ago, at a depth of approximately 15’, and native Puget soils to the south. The slopes off of the fill plateau into the Evans Creek channel are quite step in places, at a slope of 100% at the steepest. Stormwater runoff from the project site currently flows thru a series of pipes, catch basins, and overland flow into a water quality wet vault, from the wet vault into an oil water separator, and then into a pump chamber manhole where flows are pressurized up into a 5000 gallon holding tank, then pressurized again thru a force main out of the holding tank and across the creek into a permitted class 5 injection well (infiltration trench). Proposed drainage improvements include relocation of the existing above ground tank (currently inside the 25’ natural Evans Creek buffer) to be outside the buffer. Then the pump in the above ground tank will be upsized to provide adequate pressure and flow to the proposed new bioinfiltration pond. This pond is proposed to be located on the North side of the creek in the eastern portions of the site. The pond is needed to provide enhanced treatment of the runoff from the site. The pond will infiltrate the 50 year storm from the continuous model WWHM3, and release the remainder of the flows in an overflow pipe into the adjacent wetlands. The 50 year storm is what was required by the shoreline permit approval and SEPA, with the existing basin modeled as old growth forest, type C soils. A drainage basin figure has been included as Figure 2 of this report. A flowchart of minimum requirements has been included as Figure 3 of this report. The flowchart indicates that only minimum requirements #1 through #5 are required, but due to the history and complexity of this project, and the removal of the existing infiltration system, all ten minimum requirements have been addressed. ---PAGE BREAK--- ---PAGE BREAK--- TRIBUTARY PROJECT BASIN 1.80 AC PROPOSED BIOINFILTRATION POND 0.29 AC KJM KJM 02-26-13 102-009-10 PROJECT BASIN MAP ALL WOOD RECYCLING FIG 2 ---PAGE BREAK--- Figure 2.3 – Flow Chart for Determining Requirements for Redevelopment Apply Minimum Requirement Construction Stormwater Pollution Prevention Does the project add 5,000 square feet or more of new impervious surfaces? OR Convert ¾ acres or more of native vegetation to lawn or landscaped areas? OR Convert 2.5 acres or more of native vegetation to pasture? Minimum Requirements #1 through #5 apply to the new and replaced impervious surfaces and the land disturbed. Do the new, replaced, or new plus replaced impervious surfaces total 2,000 square feet or more? OR Does the land disturbing activity total 7,000 square feet or more? Minimum Requirements #1 through #10 apply to the new impervious surfaces and the converted pervious surfaces. Does the project add 5,000 square feet or more of new impervious surfaces? Is the total of the new plus replaced impervious surfaces 5,000 square feet or more, AND does the value of the proposed improvements – including interior improvements – exceed 50% of the assessed value (or replacement value) of the existing site improvements? No additional requirements Do new impervious surfaces add 50% or more to the existing impervious surfaces within the project limits? No additional requirements Minimum Requirements #1 through #10 apply to the new and replaced impervious surfaces. Yes No Next Question Yes Yes Yes Yes Next Question No No No No Is this a road- related project? Yes No 2-10 Volume I – Minimum Technical Requirements February 2005 FIGURE 3 - MINIMUM REQUIREMENTS FLOWCHART ---PAGE BREAK--- ix SECTION 2 MINIMUM REQUIREMENT #1 PREPARATION OF STORMWATER SITE PLANS ---PAGE BREAK--- x STORMWATER SITE PLANNING PROCESS The City of Redmond has adopted the 2005 Washington State Department of Ecology Stormwater management Manual for the Puget Sound Basin as the governing design document for surface runoff control. The following is a listing of the applicable minimum “core” and “special” requirements outlined in Chapter 1 of the manual, with a brief description of how each was addressed:  Step 1: Collect and Analyze Information on Existing Conditions Stormwater runoff from the project site currently flows thru a series of pipes, catch basins, and overland flow into a water quality wet vault, from the wet vault into an oil water separator, and then into a pump chamber manhole where flows are pressurized up into a 5000 gallon holding tank, then pressurized again thru a force main out of the holding tank and across the creek into a permitted class 5 injection well (infiltration trench). The project site lies in the City of Redmond, occupying King County Tax Lot #[PHONE REDACTED]. The site is covered in impervious surface, with Evans Creek bisecting the site, flowing from the SE to the NW. The topography of the site can generally be described as flat as it is on a plateau of structural fill to the north of Evans Creek placed some decades ago, at a depth of approximately 15’, and native Puget soils to the south. The slopes off of the fill plateau into the Evans Creek channel are quite step in places, at a slope of 100% at the steepest.  Step 2: Prepare a Preliminary Development Layout Proposed drainage improvements include relocation of the existing above ground tank (currently inside the 25’ natural Evans Creek buffer) to be outside the buffer. The pump in the above ground tank will be upsized to provide adequate pressure and flow to the proposed bioinfiltration pond. This pond is proposed to be located on the North side of the creek in the eastern portions of the site. The pond is needed to provide enhanced treatment of the runoff from the site. The pond has been designed to fully infiltrate runoff, up to the 50-yr peak design flowrate, as calculated from the WWHM stormwater model. An emergency overflow structure will be provided to discharge excess flows to the adjacent wetlands.  Step 3: Perform Offsite (Upstream and Analysis There are some small upstream basins to the site that is a portion of the project frontage on 192nd. The basin is very small ac) and is shown on the basin map for the site. This upstream basin is also included into the infiltration and treatment design for the site bioinfiltration pond. The drainage course for this site is Evans Creek, which flows from the east to the west thru the middle of the site. There are associated wetlands to the north and east of the site that eventually flow into Evans Creek.  Step 4: Determine Applicable Minimum Requirements The site is draining 2.09 acres, but only disturbing approximately 14,000 s.f. This includes the areas next to the creek to be restored, and the bioinfiltration pond. Section 3 of this report, along with the attached Temporary Erosion & Sediment Control (TESC) plans will serve as the for this project. The site is in the wellhead protection area, the entire 2.09 acres will be treated and infiltrated on the site, for flowrates up to the 50-year design event. ---PAGE BREAK--- xi  Step 5: Prepare a Permanent Stormwater Control Plan Surface runoff from the site is currently collected into an underground vault with multiple treatment mechanisms. Water discharged from the vault is pumped to an above-ground storage tank, then pumped again to an underground injection well on the north side of Evans Creek. The proposed design will relocate the above-ground tank outside of the 25’ Evans Creek buffer. It will remain on-site, but will be taken off-line from the stormwater management system. The project will then install a new discharge pump at the end of the treatment vault, with sufficient capacity to convey the full 50-yr peak runoff rate. This pump will direct discharge through a 4-inch force main, directly to a new bioinfiltration pond on the north side of Evans Creek. The pond will provide enhanced treatment of stormwater runoff, and has been sized to fully infiltrate the 50-year peak design storm event.  Step 6: Prepare a Stormwater Pollution Prevention Plan Section 3 of this report, along with the attached Temporary Erosion & Sediment Control (TESC) plans are intended to serve as the for this project.  Step 7: Complete the Stormwater Site Plan The stormwater site plan will be very similar to the plan developed at the preliminary stages of the project, as outlined above in step Conveyance System The conveyance proposed for this project consists of a pump and force main, to convey runoff from the underground treatment vault to the bioinfiltration pond. The pump has been designed to convey the peak flowrate for the 50-yr design storm event. A 4-inch ductile iron force main will be installed to convey stormwater from the vault to a catch basin immediately upstream of the bioinfiltration pond. The catch basin is intended to serve as an energy break to reduce the potential for erosion in the pond. A short pipe section will convey runoff from the catch basin to the bioinfiltration facility. A hydrologic analysis for the site has been provided in Appendix 8-A of this report, and includes the design flowrates for the force main system. Pump sizing calculations have been provided in Appendix 8-B. ---PAGE BREAK--- xii SECTION 3 MINIMUM REQUIREMENT #2 CONSTRUCTION STORMWATER POLLUTION PREVENTION ---PAGE BREAK--- xiii A Stormwater Pollution Prevention Plan is required to address 12 specific pollution prevention elements per SCC 30.63A. These elements are listed and summarily addressed below, A full is included in appendix 3-A. 1. Mark Clearing Limits Clearing limits will be flagged or fenced by the contractor or project surveyor prior to commencement of construction activity. 2. Establish Construction Access The site entrance is currently paved and will act as the construction entrance for equipment and material. 3. Detain Flows The project drainage will be allowed to function as existing utilizing the injection well. When the pond is complete and stabilized, the injection well will be decommissioned.. 4. Install Sediment Controls Filter fabric fencing (silt fence) shall be installed around the perimeter of the site in order to keep sediment-laden stormwater from leaving the site. The fencing shall be inspected periodically to ensure its continued effectiveness. 5. Stabilize Soils Exposed soils shall be stabilized through mulching or hydroseeding when the not actively worked for a significant period of time. Permanent vegetation shall be established through hydroseeding once the site has reached final grade. 6. Protect Slopes The project calls for the installation of silt fences on the tops of all slopes where disturbance is proposed. 7. Protect Drain Inlets The temporary erosion and sediment control plan calls for a filter fabric sock to be installed at all nearby catch basin inlets. Filter fabric protection shall be placed in all new catch basins as they are installed. 8. Stabilize Channels and Outlets Water discharged from the sedimentation facility shall outfall onto a rip-rap splash pad or level spreader. 9. Control Pollutants All waste materials shall be disposed of in an approved location, in accordance with City of Redmond Standards. In order to reasonably prevent a contamination event (such as a fuel spill), all major vehicle maintenance shall occur off-site to the greatest extent practicable. The contractor shall provide a vehicle staging area near the entrance to the site where all fueling and maintenance activity is likely to take place. This is intended to ---PAGE BREAK--- xiv contain the area in which a contamination event is likely to take place. The contractor shall immediately contain and clean-up an area in which a contamination event occurs. The existing infiltration system shall be decommissioned per Washington State Underground Injection Control (UIC) requirements. 10. Control De-Watering No significant dewatering is expected to occur during this project. 11. Maintain BMPs All BMPs should be monitored and maintained regularly to ensure adequate operation. A TESC supervisor shall be identified at the beginning of the project to provide monitoring and direct the appropriate maintenance activity. As site conditions change, all BMPs shall be updated as necessary to maintain compliance with City standards. 12. Manage the Project The project will begin with a pre-construction conference in which an on-site TESC supervisor shall be identified. The on-site supervisor shall monitor all TESC facilities regularly and maintain a log of inspections and improvements to demonstrate compliance with City standards. It will be important that the entire site is in conformance with City of Redmond erosion control standards at all times. The TESC supervisor shall notify Site Development Associates of any problems with the proposed erosion control elements, or if any revisions to the plan need to be made. Additional erosion control materials, such as filter fabric fencing, cover plastic, and straw bales, shall be kept on-site at all times in the event that an erosion control feature needs to be replaced or installed. ---PAGE BREAK--- xv APPENDIX 3-A STORMWATER POLLUTION PREVENTION PLAN ---PAGE BREAK--- i Stormwater Pollution Prevention Plan For All Wood Recycling Prepared For All Wood Recycling 8504 192nd Avenue NE Redmond, WA 98053 Owner Developer Operator/Contractor All Wood Recycling All Wood Recycling All Wood Recycling 8504 192nd Avenue NE 8504 192nd Avenue NE 8504 192nd Avenue NE Redmond, WA 98053 Redmond, WA 98053 Redmond, WA 98053 Project Site Location 8504 192nd Avenue NE Redmond, WA 98053 Certified Erosion and Sediment Control Lead Bill Helsley 4250486-6533 Prepared By Site Development Associates, LLC 1724 W. Marine View Dr., Suite 140 Everett, Washington 98201 Andrew Reaves, P.E. Preparation Date November 13, 2012 Approximate Project Construction Dates June 2013 November 2013 ---PAGE BREAK--- ii Contents 1.0 Introduction 1 2.0 Site Description 5 2.1 Existing Conditions 5 2.2 Proposed Construction Activities 5 3.0 Construction Stormwater BMPs 7 3.1 The 12 BMP Elements 7 3.1.1 Element #1 – Mark Clearing Limits 7 3.1.2 Element #2 – Establish Construction Access 7 3.1.3 Element #3 – Control Flow Rates 8 3.1.4 Element #4 – Install Sediment Controls 8 3.1.5 Element #5 – Stabilize Soils 10 3.1.6 Element #6 – Protect Slopes 11 3.1.7 Element #7 – Protect Drain Inlets 11 3.1.8 Element #8 – Stabilize Channels and Outlets 12 3.1.9 Element #9 – Control Pollutants 12 3.1.10 Element #10 – Control Dewatering 13 3.1.11 Element #11 – Maintain BMPs 13 3.1.12 Element #12 – Manage the Project 13 3.2 Site Specific BMPs 16 3.3 Additional Advanced BMPs 16 4.0 Construction Phasing and BMP Implementation 17 5.0 Pollution Prevention Team 19 5.1 Roles and Responsibilities 19 5.2 Team Members 20 6.0 Site Inspections and Monitoring 21 6.1 Site Inspection 21 6.1.1 Site Inspection Frequency 21 6.1.2 Site Inspection Documentation 22 6.2 Stormwater Quality Monitoring 22 6.2.1 Turbidity 22 6.2.2 pH 23 7.0 Reporting and Recordkeeping 25 7.1 Recordkeeping 25 7.1.1 Site Log Book 25 7.1.2 Records Retention 25 7.1.3 Access to Plans and Records 25 ---PAGE BREAK--- iii 7.1.4 Updating the 26 7.2 Reporting 26 7.2.1 Discharge Monitoring Reports 26 7.2.2 Notification of Noncompliance 26 7.2.3 Permit Application and Changes 26 Appendix A – Site Plans 27 Appendix B – Construction BMPs 30 Appendix C – Alternative BMPs 30 Appendix D – General Permit 33 Appendix E – Site Inspection Forms (and Site Log) 34 Appendix F – Engineering Calculations 44 Appendix A Site plans  Vicinity map  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 Appendix E Site Log and Inspection Forms Appendix F Engineering Calculations ---PAGE BREAK--- Stormwater Pollution Prevention Plan 1 1.0 Introduction This stormwater Pollution Prevention Plan has been prepared as part of the Shoreline Substantial Development Permit issued for the All Wood Recycling project in the city of Redmond, Washington. The site is located at 8504 192nd Avenue NE in Redmond Washington. The existing site is made up of 1 parcel totaling 4.77 acres. The existing parcel contains several structures, all of which are to remain, and for the purposes of stormwater, are not affected by this proposal or have any bearing on the drainage design or erosion control measures. The proposed development consists All Wood Recycling is a wood, concrete and asphalt recycling company occupying 4.77 acres in eastern Redmond. It is an existing use and company that has been operating on the property for approximately 18 years. This report is an analysis of the existing drainage system. The site lies in the SE ¼ of Section 6, Township 25North, Range 6 East, W.M. More specifically, the project lies at 8504 192nd Avenue, NE, Redmond Washington. A vicinity map has been provided as Figure 1 of this document. The project site occupies City of Redmond County, Tax Lot #[PHONE REDACTED]. The site is covered in impervious surface, with Evans Creek bisecting the site, flowing from the SE to the NW. The topography of the site can generally be described as flat as it is on a plateau of structural fill to the north of Evans Creek placed some decades ago, at a depth of approximately 15’, and native Puget soils to the south. The slopes off of the fill plateau into the Evans Creek channel are quite step in places, at a slope of 100% at the steepest. Stormwater runoff from the project site currently flows thru a series of pipes, catch basins, and overland flow into a water quality wet vault, from the wet vault into an oil water separator, and then into a pump chamber manhole where flows are pressurized up into a 5000 gallon holding tank, then pressurized again thru a force main out of the holding tank and across the creek into a permitted class 5 injection well (infiltration trench). Proposed drainage improvements include relocation of the existing above ground tank (currently inside the 25’ natural Evans Creek buffer) to be outside the buffer. Then the pump in the above ground tank will be upsized to provide adequate pressure and flow to the proposed new bioinfiltration pond. This pond is proposed to be located on the North side of the creek in the eastern portions of the site. The pond is needed to provide enhanced treatment of the runoff from the site. The pond will infiltrate 91% of the flows from the continuous model WWHM3, and release the remainder of the flows in an overflow pipe into the adjacent wetlands. The release rates will be at or below the allowable release rates, with the existing basin modeled as old growth forest, type C soils. The purpose of this 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 are to: ---PAGE BREAK--- Stormwater Pollution Prevention Plan 2 1. 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. 2. Prevent violations of surface water quality, ground water quality, or sediment management standards. 3. 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 of the outfalls. This was prepared using the Ecology Template downloaded from the Ecology website on April 13, 2007. This was prepared based on the requirements set forth in the Construction Stormwater General Permit, Stormwater Management Manual for Western Washington 2005) and in the Stormwater Management Manual for Eastern Washington (SWMMEW 2004). The report is divided into seven main sections with several appendices that include stormwater related reference materials. The topics presented in the each of the main sections are:  Section 1 – INTRODUCTION. This section provides a summary description of the project, and the organization of the document.  Section 2 – SITE DESCRIPTION. This section provides a detailed description of the existing site conditions, proposed construction activities, and calculated stormwater flow rates for existing conditions and post– construction conditions.  Section 3 – CONSTRUCTION BMPs. This section provides a detailed description of the BMPs to be implemented based on the 12 required elements of the (SWMMEW 2004).  Section 4 – CONSTRUCTION PHASING AND BMP IMPLEMENTATION. This section provides a description of the timing of the BMP implementation in relation to the project schedule.  Section 5 – POLLUTION PREVENTION TEAM. This section identifies the appropriate contact names (emergency and non-emergency), monitoring personnel, and the onsite temporary erosion and sedimentation control inspector  Section 6 – INSPECTION AND MONITORING. This section provides a description of the inspection and monitoring requirements such as the parameters of concern to be monitored, sample locations, sample ---PAGE BREAK--- Stormwater Pollution Prevention Plan 3 frequencies, and sampling methods for all stormwater discharge locations from the site.  Section 7 – RECORDKEEPING. This section describes the requirements for documentation of the BMP implementation, site inspections, monitoring results, and changes to the implementation of certain BMPs due to site factors experienced during construction. Supporting documentation and standard forms are provided in the following Appendices: Appendix A – Site plans Appendix B – Construction BMPs Appendix C – Alternative Construction BMP list Appendix D – General Permit Appendix E – Site Log and Inspection Forms Appendix F – Engineering Calculations ---PAGE BREAK--- Stormwater Pollution Prevention Plan 5 2.0 Site Description 2.1 Existing Conditions All Wood Recycling is a wood, concrete and asphalt recycling company occupying 4.77 acres in eastern Redmond. It is an existing use and company that has been operating on the property for approximately 18 years. This report is an analysis of the existing drainage system. The site lies in the SE ¼ of Section 6, Township 25North, Range 6 East, W.M. More specifically, the project lies at 8504 192nd Avenue, NE, Redmond Washington. A vicinity map has been provided as Figure 1 of this document. The project site occupies City of Redmond County, Tax Lot #[PHONE REDACTED]. The site is covered in impervious surface, with Evans Creek bisecting the site, flowing from the SE to the NW. The topography of the site can generally be described as flat as it is on a plateau of structural fill to the north of Evans Creek placed some decades ago, at a depth of approximately 15’, and native Puget soils to the south. The slopes off of the fill plateau into the Evans Creek channel are quite step in places, at a slope of 100% at the steepest. Stormwater runoff from the project site currently flows thru a series of pipes, catch basins, and overland flow into a water quality wet vault, from the wet vault into an oil water separator, and then into a pump chamber manhole where flows are pressurized up into a 5000 gallon holding tank, then pressurized again thru a force main out of the holding tank and across the creek into a permitted class 5 injection well (infiltration trench). Proposed drainage improvements include relocation of the existing above ground tank (currently inside the 25’ natural Evans Creek buffer) to be outside the buffer. Then the pump in the above ground tank will be upsized to provide adequate pressure and flow to the proposed new bioinfiltration pond. This pond is proposed to be located on the North side of the creek in the eastern portions of the site. The pond is needed to provide enhanced treatment of the runoff from the site. The pond will infiltrate 91% of the flows from the continuous model WWHM3, and release the remainder of the flows in an overflow pipe into the adjacent wetlands. The release rates will be at or below the allowable release rates, with the existing basin modeled as old growth forest, type C soils. 2.2 Proposed Construction Activities Proposed site improvements include relocation of the existing above ground tank (currently inside the 25’ natural Evans Creek buffer) to be outside the buffer. Then the pump in the above ground tank will be upsized to provide adequate pressure and flow to the proposed new bioinfiltration pond. This pond is proposed to be located on the North side of the creek in the eastern portions of the site. The pond is needed to provide enhanced treatment of the runoff from the site. The pond will infiltrate 91% of the flows from the continuous model WWHM3, and release the remainder of the flows in an overflow pipe into the adjacent wetlands. The release rates will be at or below the allowable release rates, with the existing basin modeled as old growth forest, type C soils. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 6 The site is draining 1.94 acres, but only disturbing approximately 14,000 s.f., which is the areas next to the creek to be restored, and the bioinfiltration pond. But as the site is in the wellhead protection area, the 1.94 acres will be treated and infiltrated on the site. There is a small portion of the drainage that will be released in a release structure (8.1% of the total event). But, all 10 minimum requirements apply. Construction activities will include site preparation, TESC installation, grading, excavation for the infiltration pond, removal of the impervious surfaces and retaining walls identified on the plans inside the 25’ natural buffer. A temporary sedimentation facility will be not be provided on the site, instead all water will be routed (pumped if necessary) into the site drainage system. It will then be routed to the existing wet vault and pumped into the sites existing infiltration system (injection well). Thus no sediment control system will be designed or constructed on the site. It should be noted that the abandonment of the existing injection well and the change to the new bio infiltration pond for treatment and discharge will occur after the pond is stabilized. The following summarizes details regarding site areas:  Total site area (that drains into drainage system): 1.94 acres  Percent impervious area before construction: 100 %  Percent impervious area after construction: 100 %  Disturbed area during construction: 0.32 acres  Disturbed area that is characterized as impervious access roads, staging, parking): 1.62 acres  2-year stormwater runoff peak flow prior to construction (existing): 0.074 cfs  10-year stormwater runoff peak flow prior to construction (existing): 0.127 cfs  2-year stormwater runoff peak flow during construction: 0.074 cfs  10-year stormwater runoff peak flow during construction: 0.127 cfs  2-year stormwater runoff peak flow after construction: 0.028 cfs ---PAGE BREAK--- Stormwater Pollution Prevention Plan 7  10-year stormwater runoff peak flow after construction: 0.066 cfs 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:  High Visibility Plastic or Metal Fence (BMP C103) Alternate BMPs for marking clearing limits are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix the Certified Erosion and Sediment Control Lead will initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. 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) Alternate construction access BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix the Certified Erosion and Sediment Control Lead will initiate the implementation of one or ---PAGE BREAK--- Stormwater Pollution Prevention Plan 8 more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. 3.1.3 Element #3 – Control Flow Rates In order to protect the properties and waterways 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:  The existing drainage system A temporary sedimentation facility will be not be provided on the site, instead all water will be routed (pumped if necessary) into the site drainage system. It will then be routed to the existing wet vault and pumped into the sites existing infiltration system (injection well). Thus no sediment control system will be designed or constructed on the site. It should be noted that the abandonment of the existing injection well and the change to the new bio infiltration pond for treatment and discharge will occur after the pond is stabilized. Alternate flow control BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix the Certified Erosion and Sediment Control Lead will initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. The project site is located west of the Cascade Mountain Crest. As such, the project must comply with Minimum Requirement 7 (Ecology 2005). In general, discharge rates of stormwater from the site will be controlled where increases in impervious area or soil compaction during construction could lead to erosion, or where necessary to meet local agency stormwater discharge requirements (e.g. discharge to combined sewer systems). 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) ---PAGE BREAK--- Stormwater Pollution Prevention Plan 9  Materials on Hand (BMP C150) may also be applicable Silt fence will be placed just inside of the clearing and grading limits around the entire site perimeter prior to any clearing or grading. Storm drain inlet projection will be provided at all catch basins immediately after installation. Erosion prevention and sediment control materials will be kept on the project site at all times, stockpiled and readily available. The proposed sediment ponds will be used as settling basins during construction. Alternate sediment control BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix the Certified Erosion and Sediment Control Lead will initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. 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 wash off of sediments from adjacent streets in runoff. Whenever possible, sediment laden water shall be discharged into onsite, relatively level, vegetated areas (BMP C240 paragraph 5, page 4-102). In some cases, sediment discharge in concentrated runoff can be controlled using permanent stormwater BMPs infiltration swales, ponds, trenches). Sediment loads can limit the effectiveness of some permanent stormwater BMPs, such as those used for infiltration or biofiltration; however, those BMPs designed to remove solids by settling (wet ponds or detention ponds) can be used during the construction phase. When permanent stormwater BMPs will be used to control sediment discharge during construction, the structure will be protected from excessive sedimentation with adequate erosion and sediment control BMPs. Any accumulated sediment shall be removed after construction is complete and the permanent stormwater BMP will be restabilized with vegetation per applicable design requirements once the remainder of the site has been stabilized. The following BMPs will be implemented as end-of-pipe sediment controls as required to meet permitted turbidity limits in the site discharge(s). Prior to the implementation of these technologies, sediment sources and erosion control and soil stabilization BMP efforts will be maximized to reduce the need for end-of-pipe sedimentation controls.  Temporary Sediment Pond (BMP C241)  Construction Stormwater Filtration (BMP C251) ---PAGE BREAK--- Stormwater Pollution Prevention Plan 10  Construction Stormwater Chemical Treatment (BMP C 250) (implemented only with prior written approval from Ecology). 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)  Plastic Covering (BMP C123)  Dust Control (BMP C140)  Early application of gravel base on areas to be paved Seeding will be used on disturbed areas that have reached final grade or that will remain unworked for more than thirty days. Plastic Covering will be used on the temporary stock pile areas and elsewhere on the site as needed. Dust control will be implemented as needed, to prevent it being required all roadways and driveways to be paved will receive early application of gravel base. Alternate soil stabilization BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix the Certified Erosion and Sediment Control Lead will initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. The project site is located west of the Cascade Mountain Crest. As such, no soils shall remain exposed and unworked for more than 7 days during the dry season (May 1 to September 30) and 2 days during the wet season (October 1 to April 30). Regardless of the time of year, all soils shall be stabilized at the end of the shift before a holiday or weekend if needed based on weather forecasts. In general, cut and fill slopes will be stabilized as soon as possible and soil stockpiles will be temporarily covered with plastic sheeting. 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. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 11 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:  Temporary and Permanent Seeding (BMP C120)  Interceptor Dike and Swale (BMP C200)  Check Dams (BMP C207)  Materials on Hand (BMP C150) Alternate slope protection BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix the Certified Erosion and Sediment Control Lead will initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. 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:  Gravel and Wire Drop Inlet Protection  Catch Basin Filters  Alternative BMP not included in the (2005) or SWMMEW (2004) If the BMP options listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix or if no BMPs are listed above but deemed necessary during construction, the Certified Erosion and Sediment Control Lead shall implement one or more of the alternative BMP inlet protection options listed in Appendix C. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 12 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 erosion. The specific BMPs for channel and outlet stabilization that shall be used on this project include:  Check Dams (BMP C207) Alternate channel and outlet stabilization BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix the Certified Erosion and Sediment Control Lead will initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. The project site is located west of the Cascade Mountain Crest. As such, all temporary on-site conveyance channels shall be designed, constructed, and stabilized to prevent erosion from the expected peak 10 minute velocity of flow from a Type 1A, 10-year, 24- hour recurrence interval storm for the developed condition. Alternatively, the 10-year, 1- hour peak flow rate indicated by an approved continuous runoff simulation model, increased by a factor of 1.6, shall be used. Stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent streambanks, slopes, and reaches shall be provided at the outlets of all conveyance systems. 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.  Spill prevention measures, such as drip pans, will be used when conducting maintenance and repair of vehicles or equipment. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 13  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. Concrete and grout:  Process water and slurry resulting from concrete work will be prevented from entering the waters of the State by implementing Concrete Handling measures (BMP C151). Solid Waste:  Solid waste will be stored in secure, clearly marked containers. 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 as part of this construction project. 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. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 14  Emphasize erosion control rather than sediment control.  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. 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. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 15  The following activities are exempt from the seasonal clearing and grading limitations:  Routine maintenance and necessary repair of erosion and sediment control BMPs;  Routine maintenance of public facilities or existing utility structures that do not expose the soil or result in the removal of the vegetative cover to soil; and  Activities 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 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  Assess the effectiveness of erosion and sediment control measures used to control the quality of stormwater discharges.  A Certified Erosion and Sediment Control Lead shall be on-site or on-call at all times.  Whenever inspection and/or monitoring reveals that the BMPs identified in this 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. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 16 Maintaining an Updated Construction  This shall be retained on-site or within reasonable access to the site.  The shall be modified whenever there is a change in the design, construction, operation, or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the state.  The 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 is ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site. The shall be modified as necessary to include additional or modified BMPs designed to correct problems identified. Revisions to the shall be completed within seven days following the inspection. 3.2 Site Specific BMPs Site specific BMPs are shown on the TESC Plan Sheets and Details in Appendix A. These site specific plan sheets will be updated annually. 3.3 Additional Advanced BMPs ---PAGE BREAK--- Stormwater Pollution Prevention Plan 17 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.  Estimate of Construction Start Date June 2013  Estimate of Construction End Date October 2013  Mobilize equipment on site: June 2012  Mobilize and store all ESC and soil stabilization products: June 2012  Install ESC measures: June 2012  Install stabilized construction entrance: N/A  Begin clearing and grubbing: June 2012 ---PAGE BREAK--- Stormwater Pollution Prevention Plan 19 5.0 Pollution Prevention Team 5.1 Roles and Responsibilities The pollution prevention team consists of personnel responsible for implementation of the including the following:  Certified Erosion and Sediment Control Lead (CESCL) – primary contractor contact, responsible for site inspections (BMPs, visual monitoring, sampling, 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 Ecology Contact – individual to be contacted at Ecology in case of emergency.  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 Ecology Contact – individual that is the site owner or representative of the site owner than can be contacted if required.  Monitoring Personnel – personnel responsible for conducting water quality monitoring; for most sites this person is also the Certified Erosion and Sediment Control Lead. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 20 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 Certified Erosion and Sediment Control Lead (CESCL) Bill Helsley [PHONE REDACTED] Resident Engineer Andrew Reaves [PHONE REDACTED] Emergency Ecology Contact Puget Sound Office [PHONE REDACTED] Emergency Owner Contact Andrew Reaves [PHONE REDACTED] Non-Emergency Ecology Contact Northwest Region [PHONE REDACTED] Monitoring Personnel Andrew Reaves [PHONE REDACTED] ---PAGE BREAK--- Stormwater Pollution Prevention Plan 21 6.0 Site Inspections and Monitoring Monitoring includes visual inspection, monitoring for water quality parameters of concern, and documentation of the inspection and monitoring 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 and other permit requirements;  Site inspections; and,  Stormwater quality monitoring. For convenience, the inspection form and water quality monitoring forms included in this include the required information for the site log book. This 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 Ecology or the local jurisdiction. 6.1 Site Inspection All BMPs will be inspected, maintained, and repaired as needed to assure continued performance of their intended function. The inspector will be a Certified Erosion and Sediment Control Lead (CESCL) per BMP C160. The name and contact information for the CESCL is provided in Section 5 of this 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 as soon as possible. 6.1.1 Site Inspection Frequency Site inspections will be conducted at least once a week and within 24 hours following any rainfall event which causes a discharge of stormwater from the site. For sites with temporary stabilization measures, the site inspection frequency can be reduced to once every month. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 22 6.1.2 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 document, but will be maintained on-site or within reasonable access to the site and be made available upon request to Ecology or the local jurisdiction. 6.2 Stormwater Quality Monitoring 6.2.1 Turbidity Sampling Monitoring requirements for the proposed project will include turbidity sampling to monitor site discharges for water quality compliance with the 2005 Construction Stormwater General Permit (Appendix Sampling will be conducted at all site discharge points at least once per calendar week. Turbidity monitoring will follow the analytical methodologies described in Section S4 of the 2005 Construction Stormwater General Permit (Appendix The key benchmark values that require action include 25 NTU and 250 NTU for turbidity. If the 25 NTU benchmark for turbidity is exceeded, the following steps will be conducted: 1. Ensure all BMPs specified in this are installed and functioning as intended. 2. Assess whether additional BMPs should be implemented and make revisions to the as necessary. 3. Sample the discharge location daily until the analysis results are less than 25 NTU (turbidity) or 32 cm (transparency). If the turbidity is greater than 25 NTU but less than 250 NTU for more than 3 days, additional treatment BMPs will be implemented within 24 hours of the third consecutive sample that exceeded the benchmark value. Additional treatment BMPs will include, but are not limited to, off-site treatment, infiltration, filtration and chemical treatment. If the 250 NTU benchmark for turbidity is exceeded at any time, the following steps will be conducted: 1. Notify Ecology by phone within 24 hours of analysis. 2. Continue daily sampling until the turbidity is less than 25 NTU. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 23 3. Initiate additional treatment BMPs such as off-site treatment, infiltration, filtration and chemical treatment within 24 hours of the first 250 NTU exceedance. 4. Implement additional treatment BMPs as soon as possible, but within 7 days of the first 250 NTU exceedance. 5. Describe inspection results and remedial actions that are taken in the site log book and in discharge monitoring reports. 6.2.2 pH Sampling Stormwater runoff will be monitored for pH starting on the first day of any activity that includes more than 40 yards of poured or recycled concrete, or after the application of “Engineered Soils” such as, Portland cement treated base, cement kiln dust, or fly ash. This does not include fertilizers. For concrete work, pH monitoring will start the first day concrete is poured and continue until 3 weeks after the last pour. For engineered soils, the pH monitoring period begins when engineered soils are first exposed to precipitation and continue until the area is fully stabilized. Stormwater samples will be collected daily from all points of discharge from the site and measured for pH using a calibrated pH meter, pH test kit, or wide range pH indicator paper. If the measured pH is 8.5 or greater, the following steps will be conducted: 1. Prevent the high pH water from entering storm drains or surface water. 2. Adjust or neutralize the high pH water if necessary using appropriate technology such as CO2 sparging (liquid or dry ice). 3. Contact Ecology if chemical treatment other than CO2 sparging is planned. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 25 7.0 Reporting and Recordkeeping 7.1 Recordkeeping 7.1.1 Site Log Book A site log book will be maintained for all on-site construction activities and will include:  A record of the implementation of the and other permit requirements;  Site inspections; and,  Stormwater quality monitoring. For convenience, the inspection form and water quality monitoring forms included in this include the required information for the site log book. 7.1.2 Records Retention Records of all monitoring information (site log book, inspection reports/checklists, etc.), this Stormwater Pollution Prevention Plan, and any other documentation of compliance with permit requirements will be retained during the life of the construction project and for a minimum of three years following the termination of permit coverage in accordance with permit condition S5.C. 7.1.3 Access to Plans and Records The General Permit, Notice of Authorization letter, 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 Ecology or the local jurisdiction. A copy of this will be provided to Ecology within 14 days of receipt of a written request for the from Ecology. Any other information requested by Ecology will be submitted within a reasonable time. A copy of the or access to the will be provided to the public when requested in writing in accordance with permit condition S5.G. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 26 7.1.4 Updating the In accordance with Conditions S3, S4.B, and S9.B.3 of the General Permit, this will be modified if the 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 will be modified within seven days of determination based on inspection(s) that additional or modified BMPs are necessary to correct problems identified, and an updated timeline for BMP implementation will be prepared. 7.2 Reporting 7.2.1 Discharge Monitoring Reports Discharge Monitoring Report (DMR) forms will not be submitted to Ecology because water quality sampling is not being conducted at the site. 7.2.2 Notification of Noncompliance If any of the terms and conditions of the permit are not met, and it causes a threat to human health or the environment, the following steps will be taken in accordance with permit section S5.F: 1. Ecology will be immediately notified of the failure to comply. 2. Immediate action will be taken to control the noncompliance issue and to correct the problem. If applicable, sampling and analysis of any noncompliance will be repeated immediately and the results submitted to Ecology within five days of becoming aware of the violation. 3. A detailed written report describing the noncompliance will be submitted to Ecology within five days, unless requested earlier by Ecology. In accordance with permit condition S2.A, a complete application form will be submitted to Ecology and the appropriate local jurisdiction (if applicable) to be covered by the General Permit. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 27 Appendix A – Site Plans ---PAGE BREAK--- Stormwater Pollution Prevention Plan 28 ---PAGE BREAK--- Stormwater Pollution Prevention Plan 30 Appendix B – Construction BMPs High Visibility Plastic or Metal Fence (BMP C103) Silt Fence (BMP C233) Storm Drain Inlet Protection (BMP C220) Materials on Hand (BMP C150) may also be applicable Detention Pond Or Vault Temporary and Permanent Seeding (BMP C120) Plastic Covering (BMP C123) Topsoiling (BMP C125) Dust Control (BMP C140) Early application of gravel base on areas to be paved Temporary and Permanent Seeding (BMP C120) Interceptor Dike and Swale (BMP C200) Check Dams (BMP C207) Materials on Hand (BMP C150) Grass-Lined Channels (BMP C201) Check Dams (BMP C207) Appendix C – Alternative BMPs ---PAGE BREAK--- Stormwater Pollution Prevention Plan 31 The following includes a list of possible alternative BMPs for each of the 12 elements not described in the main text. This list can be referenced in the event a BMP for a specific element is not functioning as designed and an alternative BMP needs to be implemented. Element #1 - Mark Clearing Limits High Visibility Plastic or Metal Fence (BMP C103) Element #2 - Establish Construction Access Wheel Wash (BMP C106) Element #3 - Control Flow Rates Alternative BMP not included in the (2005) Element #4 - Install Sediment Controls Straw Bale Barrier (BMP C230) Vegetated Strip (BMP C234) Materials on Hand (BMP C150) Advanced BMPs: Element #5 - Stabilize Soils Dust Control (BMP C140) Topsoiling (BMP C125) Sodding (BMP C124) Element #6 - Protect Slopes Straw Wattles (BMP C235) Grass-Lined Channels (BMP C201) Element #8 - Stabilize Channels and Outlets Level Spreader (BMP C206) ---PAGE BREAK--- Stormwater Pollution Prevention Plan 32 Element #10 - Control Dewatering There will be no dewatering as part of this project. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 33 Appendix D – General Permit ---PAGE BREAK--- Stormwater Pollution Prevention Plan 34 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 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 r 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 and the NPDES permit. 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. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 35 i. 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”. When the site inspection indicates that the site is not in compliance with any terms and conditions of the NPDES permit, the Permittee shall take immediate action(s) to: stop, contain, and clean up the unauthorized discharges, or otherwise stop the noncompliance; correct the problem(s); implement appropriate Best Management Practices (BMPs), and/or conduct maintenance of existing BMPs; and achieve compliance with all applicable standards and permit conditions. In addition, if the noncompliance causes a threat to human health or the environment, the Permittee shall comply with the Noncompliance Notification requirements in Special Condition S5.F of the permit. ---PAGE BREAK--- Stormwater Pollution Prevention Plan 36 Site Inspection Form General Information Project Name: Inspector Name: Title: CESCL # : Date: Time: Inspection Type: □ After a rain event □ Weekly □ Turbidity/transparency benchmark exceedance □ 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 Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 2: Establish Construction Access BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP ---PAGE BREAK--- Stormwater Pollution Prevention Plan 37 BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 3: Control Flow Rates BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 4: Install Sediment Controls BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP ---PAGE BREAK--- Stormwater Pollution Prevention Plan 38 BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP ---PAGE BREAK--- Stormwater Pollution Prevention Plan 39 Element 5: Stabilize Soils BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 6: Protect Slopes BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP ---PAGE BREAK--- Stormwater Pollution Prevention Plan 40 BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 7: Protect Drain Inlets BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 8: Stabilize Channels and Outlets BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP ---PAGE BREAK--- Stormwater Pollution Prevention Plan 41 BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 9: Control Pollutants BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Element 10: Control Dewatering BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP ---PAGE BREAK--- Stormwater Pollution Prevention Plan 42 BMP: Location Inspected Functionin g Problem/Corrective Action Y N Y N NIP Stormwater Discharges From the Site Observed? Problem/Corrective Action Y N Location Turbidity Discoloration Sheen Location Turbidity Discoloration Sheen ---PAGE BREAK--- Stormwater Pollution Prevention Plan 43 Water Quality Monitoring Was any water quality monitoring conducted? □ Yes □ 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 □ 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? □ Yes □ No If photos taken, describe photos below: ---PAGE BREAK--- Stormwater Pollution Prevention Plan 44 Appendix F – Engineering Calculations ---PAGE BREAK--- Stormwater Pollution Prevention Plan 45 SECTION 8.6 TESC CALCULATIONS ---PAGE BREAK--- Stormwater Pollution Prevention Plan 46 Basin A – This basin is located on the northwestern portion of the site and will contain 1.37 acres. Flow will travel in a westerly direction in a proposed interceptor swale and discharge into proposed sediment trap which will discharge treated stormwater into the adjacent on site wetland. Basin A Steps 1. Obtain the sediment trap volume (2 year/24 hour developed storm). Vol2yr/ 24hr = 0.07 Ac-ft = 3,050 cf (see attached tables) 2. Determine the Average Surface Area (SA) required to provide 3,050 cf of storage The detention vault will be used for desiment storage, Vault SA = 20’ X 64, storage depth is 6.25’ as the orifice will be blocked Thus volume is 20 x 64 x 6.25 = 8,000 s.f. Thus, the detention vault would provide adequate temporary storage with the bottom orifice blocked. Basin B – This basin is located on the southern portion of the site and will contain approximately 5.35 acres. Flow will travel to the west and discharge into proposed sediment pond which will discharge treated stormwater into the adjacent on site wetland. Basin D Steps 1. Obtain the sediment trap volume (10 year/24 hour developed storm). Vol10yr/ 24hr = 0.45 Ac-ft = 19,600 cf (see attached tables) 2. Determine the Average Surface Area (SA) required to provide 19,600 cf of storage (Assuming 8’ depth, which is the depth of the permanent pond) SA = 2,450 SF = 55’ X 44’, Permanent pond dimensions are 79’ X 68’ 3’ of sediment storage is required, 4’ of sediment storage is provided. The pond with top dimensions of 79’ x 68’ will provide adequate temporary storage. Basin C – This basin is located on the southern portion of the site and will contain approximately 5.42 acres. Flow will travel to the west and discharge into proposed sediment pond which will discharge treated stormwater into the adjacent on site wetland. Basin D Steps 1. Obtain the sediment trap volume (10 year/24 hour developed storm). Vol10yr/ 24hr = 0.45 Ac-ft = 19,600 cf (see attached tables) 2. Determine the Average Surface Area (SA) required to provide 19,600 cf of storage (Assuming 8’ depth, which is the depth of the permanent pond) SA = 2,450 SF = 55’ X 44’, Permanent pond dimensions are 79’ X 68’ 3’ of sediment storage is required, 4’ of sediment storage is provided. The pond with top dimensions of 79’ x 68’ will provide adequate temporary storage. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 4 MINIMUM REQUIREMENT #3 SOURCE CONTROL OF POLLUTION ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SOURCE CONTROL The project proposes a number of source control BMPs, due to the current site use. These source control recommendations are provided in Appendix 4-A. A spill control plan has also been prepared for the project, which is provided in Appendix 4-B. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report APPENDIX 4-A SOURCE CONTROL BMPS ---PAGE BREAK--- BMPs for Dust Control at Disturbed Land Areas and Unpaved Roadways and Parking Lots Description of Pollutant Sources: Dust can cause air and water pollution problems particularly at demolition sites and in arid areas where reduced rainfall exposes soil particles to transport by air. Pollutant Control Approach: Minimize dust generation and apply environmentally friendly and government approved dust suppressant chemicals, if necessary. Applicable Operational BMPs: x Sprinkle or wet down soil or dust with water as long as it does not result in a wastewater discharge. x Use only local and/or state government approved dust suppressant chemicals such as those listed in Ecology Publication #96-433, “Techniques for Dust Prevention and Suppression.” x Avoid excessive and repeated applications of dust suppressant chemicals. Time the application of dust suppressants to avoid or minimize their wash-off by rainfall or human activity such as irrigation. x Apply stormwater containment to prevent the conveyance of stormwater TSS into storm drains or receiving waters. x The use of motor oil for dust control is prohibited. Care should be taken when using lignin derivatives and other high BOD chemicals in excavations or areas easily accessible to surface water or ground water. x Consult with the Ecology Regional Office in your area on discharge permit requirements if the dust suppression process results in a wastewater discharge to the ground, ground water, storm drain, or surface water. Recommended Additional Operational BMPs for Roadways and Other Trafficked Areas: x Consider limiting use of off-road recreational vehicles on dust generating land. x Consider paving unpaved permanent roads and other trafficked areas at municipal, commercial, and industrial areas. x Consider paving or stabilizing shoulders of paved roads with gravel, vegetation, or local government approved chemicals. x Encourage use of alternate paved routes, if available. x Vacuum or wet sweep fine dirt and skid control materials from paved roads soon after winter weather ends or when needed. x Consider using traction sand that is pre-washed to reduce dust emissions. 2-16 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- Additional Recommended Operational BMPs for Dust Generating Areas: x Prepare a dust control plan. Helpful references include: Control of Open Fugitive Dust Sources (EPA-450/3-88-088), and Fugitive Dust Background Document and Technical Information Document for Best Available Control Measures (EPA-450/2-92-004) x Limit exposure of soil (dust source) as much as feasible. x Stabilize dust-generating soil by growing and maintaining vegetation, mulching, topsoiling, and/or applying stone, sand, or gravel. x Apply windbreaks in the soil such as trees, board fences, tarp curtains, bales of hay, etc. x Cover dust-generating piles with wind-impervious fabric, or equivalent material. February 2005 Volume IV - Source Control BMPs 2-17 ---PAGE BREAK--- BMPs for Fueling At Dedicated Stations Description of Pollutant Sources: A fueling station is a facility dedicated to the transfer of fuels from a stationary pumping station to mobile vehicles or equipment. It includes above or under-ground fuel storage facilities. In addition to general service gas stations, fueling may also occur at 24-hour convenience stores, construction sites, warehouses, car washes, manufacturing establishments, port facilities, and businesses with fleet vehicles. Typically, stormwater contamination at fueling stations is caused by leaks/spills of fuels, lube oils, radiator coolants, and vehicle washwater. Pollutant Control Approach: New or substantially remodeled* fueling stations must be constructed on an impervious concrete pad under a roof to keep out rainfall and stormwater run-on. A treatment BMP must be used for contaminated stormwater and wastewaters in the fueling containment area. * Substantial remodeling includes replacing the canopy, or relocating or adding one or more fuel dispensers in such a way that the Portland cement concrete (or equivalent) paving in the fueling area is modified. For new or substantially remodeled Fueling Stations: Applicable Operational BMPs: x Prepare an emergency spill response and cleanup plan (per BMPs for Spills of Oil and Hazardous Substances) and have designated trained person(s) available either on site or on call at all times to and properly implement that plan and immediately cleanup all spills. Keep suitable cleanup materials, such as dry adsorbent materials, on site to allow prompt cleanup of a spill. x Train employees on the proper use of fuel dispensers. Post signs in accordance with the Uniform Fire Code (UFC). Post “No Topping Off” signs (topping off gas tanks causes spillage and vents gas fumes to the air). Make sure that the automatic shutoff on the fuel nozzle is functioning properly. x The person conducting the fuel transfer must be present at the fueling pump during fuel transfer, particularly at unattended or self-serve stations. x Keep drained oil filters in a suitable container or drum. Applicable Structural Source Control BMPs: x Design the fueling island to control spills (dead-end sump or spill control separator in compliance with the UFC), and to treat collected stormwater and/or wastewater to required levels. Slope the concrete containment pad around the fueling island toward drains; either trench drains, catch basins and/or a dead-end sump. The slope of the drains shall not be less than 1 percent (Section 7901.8 of the UFC). Drains to February 2005 Volume IV - Source Control BMPs 2-19 ---PAGE BREAK--- treatment shall have a shutoff valve, which must be closed in the event of a spill. The spill control sump must be sized in compliance with Section 7901.8 of the UFC; or x Design the fueling island as a spill containment pad with a sill or berm raised to a minimum of four inches (Section 7901.8 of the UFC) to prevent the runoff of spilled liquids and to prevent run-on of stormwater from the surrounding area. Raised sills are not required at the open-grate trenches that connect to an approved drainage-control system. x The fueling pad must be paved with Portland cement concrete, or equivalent. Asphalt is not considered an equivalent material. x The fueling island must have a roof or canopy to prevent the direct entry of precipitation onto the spill containment pad (see Figure 2.1). The roof or canopy should, at a minimum, cover the spill containment pad (within the grade break or fuel dispensing area) and preferably extend several additional feet to reduce the introduction of windblown rain. Convey all roof drains to storm drains outside the fueling containment area. Figure 2.1 – Covered Fuel Island x Stormwater collected on the fuel island containment pad must be conveyed to a sanitary sewer system, if approved by the sanitary authority; or to an approved treatment system such as an oil/water separator and a basic treatment BMP. (Basic treatment BMPs are listed in Volume V and include media filters and biofilters) Discharges from treatment systems to storm drains or surface water or to the ground must not display ongoing or recurring visible sheen and must not contain greater than a significant amount of oil and grease. 2-20 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- x Alternatively, stormwater collected on the fuel island containment pad may be collected and held for proper off site disposal. x Conveyance of any fuel-contaminated stormwater to a sanitary sewer must be approved by the local sewer authority and must comply with pretreatment regulations (WAC 173-216-060). These regulations prohibit discharges that could "cause fire or explosion. An explosive or flammable mixture is defined under state and federal pretreatment regulations, based on a flash point determination of the mixture. If contaminated stormwater is determined not to be explosive, then it could be conveyed to a sanitary sewer system. x Transfer the fuel from the delivery tank trucks to the fuel storage tank in impervious contained areas and ensure that appropriate overflow protection is used. Alternatively, cover nearby storm drains during the filling process and use drip pans under all hose connections. Additional BMP for Vehicles 10 feet in height or greater A roof or canopy may not be practicable at fueling stations that regularly fuel vehicles that are 10 feet in height or greater, particularly at industrial or WSDOT sites. At those types of fueling facilities, the following BMPs apply, as well as the applicable BMPs and fire prevention (UFC requirements) of this BMP for fueling stations: x If a roof or canopy is impractical the concrete fueling pad must be equipped with emergency spill control, which includes a shutoff valve for the drainage from the fueling area. The valve must be closed in the event of a spill. An electronically actuated valve is preferred to minimize the time lapse between spill and containment. Spills must be cleaned up and disposed off-site in accordance with BMPs for Spills of Oil and Hazardous Substances. x The valve may be opened to convey contaminated stormwater to a sanitary sewer, if approved by the sewer authority, or to oil removal treatment such as an API or CP oil/water separator, catchbasin insert, or equivalent treatment, and then to a basic treatment BMP. Discharges from treatment systems to storm drains or surface water or to the ground must not display ongoing or recurring visible sheen and must not contain greater than a significant amount of oil and grease. An explosive or flammable mixture is defined under state and federal pretreatment regulations, based on a flash point determination of the mixture. If contaminated stormwater is determined not to be explosive or) then it could be conveyed to a sanitary sewer system. February 2005 Volume IV - Source Control BMPs 2-21 ---PAGE BREAK--- BMPs for Loading and Unloading Areas for Liquid or Solid Material Description of Pollutant Sources: Loading/unloading of liquid and solid materials at industrial and commercial facilities are typically conducted at shipping and receiving, outside storage, fueling areas, etc. Materials transferred can include products, raw materials, intermediate products, waste materials, fuels, scrap metals, etc. Leaks and spills of fuels, oils, powders, organics, heavy metals, salts, acids, alkalis, etc. during transfer are potential causes of stormwater contamination. Spills from hydraulic line breaks are a common problem at loading docks. Pollutant Control Approach: Cover and contain the loading/ unloading area where necessary to prevent run-on of stormwater and runoff of contaminated stormwater. Applicable Operational BMPs: At All Loading/ Unloading Areas: x A significant amount of debris can accumulate at outside, uncovered loading/unloading areas. Sweep these surfaces frequently to remove material that could otherwise be washed off by stormwater. Sweep outside areas that are covered for a period of time by containers, logs, or other material after the areas are cleared. x Place drip pans, or other appropriate temporary containment device, at locations where leaks or spills may occur such as hose connections, hose reels and filler nozzles. Drip pans shall always be used when making and breaking connections (see Figure 2.2). Check loading/ unloading equipment such as valves, pumps, flanges, and connections regularly for leaks and repair as needed. Figure 2.2 – Drip Pan February 2005 Volume IV - Source Control BMPs 2-29 ---PAGE BREAK--- At Tanker Truck and Rail Transfer Areas to Above/Below-ground Storage Tanks: x To minimize the risk of accidental spillage, prepare an "Operations Plan" that describes procedures for loading/unloading. Train the employees, especially fork lift operators, in its execution and post it or otherwise have it readily available to employees. x Report spills of reportable quantities to Ecology (refer to Section 2.1 for telephone numbers of Ecology Regional Offices). x Prepare and implement an Emergency Spill Cleanup Plan for the facility (BMP Spills of Oil and Hazardous Substances) which includes the following BMPs:  Ensure the clean up of liquid/solid spills in the loading/ unloading area immediately, if a significant spill occurs, and, upon completion of the loading/unloading activity, or, at the end of the working day.  Retain and maintain an appropriate oil spill cleanup kit on-site for rapid cleanup of material spills. (See BMP Spills of Oil and Hazardous Substances).  Ensure that an employee trained in spill containment and cleanup is present during loading/unloading. At Rail Transfer Areas to Above/below-ground Storage Tanks: Install a drip pan system as illustrated (see Figure 2.3) within the rails to collect spills/leaks from tank cars and hose connections, hose reels, and filler nozzles. Figure 2.3 – Drip Pan Within Rails 2-30 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- Loading/Unloading from/to Marine Vessels: Facilities and procedures for the loading or unloading of petroleum products must comply with Coast Guard requirements specified in Appendix IV-D R.5. Transfer of Small Quantities from Tanks and Containers: Refer to BMPs Storage of Liquids in Permanent Above-Ground Tanks, and Storage of Liquid, Food Waste, or Dangerous Waste Containers, for requirements on the transfer of small quantities from tanks and containers, respectively. Applicable Structural Source Control BMPs: At All Loading/ Unloading Areas: x Consistent with Uniform Fire Code requirements (Appendix IV-D R.2) and to the extent practicable, conduct unloading or loading of solids and liquids in a manufacturing building, under a roof, or lean-to, or other appropriate cover. x Berm, dike, and/or slope the loading/unloading area to prevent run-on of stormwater and to prevent the runoff or loss of any spilled material from the area. x Large loading areas frequently are not curbed along the shoreline. As a result, stormwater passes directly off the paved surface into surface water. Place curbs along the edge, or slope the edge such that the stormwater can flow to an internal storm drain system that leads to an approved treatment BMP. x Pave and slope loading/unloading areas to prevent the pooling of water. The use of catch basins and drain lines within the interior of the paved area must be minimized as they will frequently be covered by material, or they should be placed in designated “alleyways” that are not covered by material, containers or equipment. Recommended Structural Source Control BMP: For the transfer of pollutant liquids in areas that cannot contain a catastrophic spill, install an automatic shutoff system in case of unanticipated off-loading interruption (e.g. coupling break, hose rupture, overfill, etc.). At Loading and Unloading Docks: x Install/maintain overhangs, or door skirts that enclose the trailer end (see Figures 2.4 and 2.5) to prevent contact with rainwater. x Design the loading/unloading area with berms, sloping, etc. to prevent the run-on of stormwater. x Retain on-site the necessary materials for rapid cleanup of spills. February 2005 Volume IV - Source Control BMPs 2-31 ---PAGE BREAK--- Volume IV - Source Control BMPs February 2005 Figure 2.4 – Loading Dock with Door Skirt Figure 2.5 – Loading Dock with Overhang At Tanker Truck Transfer Areas to Above/Below-Ground Storage Tanks: x Pave the area on which the transfer takes place. If any transferred liquid, such as gasoline, is reactive with asphalt pave the area with Portland cement concrete. x Slope, berm, or dike the transfer area to a dead-end sump, spill containment sump, a spill control (SC) oil/water separator, or other spill control device. The minimum spill retention time should be 15 minutes at the greater flow rate of the highest fuel dispenser nozzle through-put rate, or the peak flow rate of the 6-month, 24-hour storm event over the surface of the containment pad, whichever is greater. The volume of the spill containment sump should be a minimum of 50 gallons with an adequate grit sedimentation volume. 2-32 ---PAGE BREAK--- BMPs for Log Sorting and Handling Description of Pollutant Sources: Log yards are paved or unpaved areas where logs are transferred, sorted, debarked, cut, and stored to prepare them for shipment or for the production of dimensional lumber, plywood, chips, poles, or other products. Log yards are generally maintained at sawmills, shipping ports, and pulp mills. Typical pollutants include oil and grease, BOD, settleable solids, total suspended solids (including soil), high and low pH, heavy metals, pesticides, wood-based debris, and leachate. The following are pollutant sources: x Log storage, rollout, sorting, scaling, and cutting areas x Log and liquid loading areas x Log sprinkling x Debarking, bark bin and conveyor areas x Bark, ash, sawdust and wood debris piles, and other solid wastes x Metal salvage areas x Truck, rail, ship, stacker, and loader access areas x Log trucks, stackers, loaders, forklifts, and other heavy equipment x Maintenance shops and parking areas x Cleaning areas for vehicles, parts, and equipment x Storage and handling areas for hydraulic oils, lubricants, fuels, paints, liquid wastes, and other liquid materials x Pesticide usage for log preservation and surface protection x Application of herbicides for weed control x Contaminated soil resulting from leaks or spills of fluids Ecology’s Baseline General Permit Requirements: Industries with log yards are required to obtain coverage under the baseline general permit for discharges of stormwater associated with industrial activities to surface water. The permit requires preparation and on-site retention of Stormwater Pollution Prevention Plans The must identify operational, source control, erosion and sediment control and, if necessary, treatment BMPs. Required and recommended operational, source control, and treatment BMPs are presented in detail in Ecology’s Guidance Document: ”Industrial Stormwater General Permit Implementation Manual for Log Yards, Publication # 04-10-031. It is recommended that all log yard facilities obtain a copy of this document. February 2005 Volume IV - Source Control BMPs 2-33 ---PAGE BREAK--- BMPs for Maintenance and Repair of Vehicles and Equipment Description of Pollutant Sources: Pollutant sources include parts/vehicle cleaning, spills/leaks of fuel and other liquids, replacement of liquids, outdoor storage of batteries/liquids/parts, and vehicle parking. Pollutant Control Approach: Control of leaks and spills of fluids using good housekeeping and cover and containment BMPs. Applicable Operational BMPs: x Inspect for leaks all incoming vehicles, parts, and equipment stored temporarily outside. x Use drip pans or containers under parts or vehicles that drip or that are likely to drip liquids, such as during dismantling of liquid containing parts or removal or transfer of liquids. x Remove batteries and liquids from vehicles and equipment in designated areas designed to prevent stormwater contamination. Store cracked batteries in a covered non-leaking secondary containment system. x Empty oil and fuel filters before disposal. Provide for proper disposal of waste oil and fuel. x Do not pour/convey washwater, liquid waste, or other pollutant into storm drains or to surface water. Check with the local sanitary sewer authority for approval to convey to a sanitary sewer. x Do not connect maintenance and repair shop floor drains to storm drains or to surface water. To allow for snowmelt during the winter a drainage trench with a sump for particulate collection can be installed and used only for draining the snowmelt and not for discharging any vehicular or shop pollutants. Applicable Structural Source Control BMPs: x Conduct all maintenance and repair of vehicles and equipment in a building, or other covered impervious containment area that is sloped to prevent run-on of uncontaminated stormwater and runoff of contaminated stormwater. x The maintenance of refrigeration engines in refrigerated trailers may be conducted in the parking area with due caution to avoid the release of engine or refrigeration fluids to storm drains or surface water. x Park large mobile equipment, such as log stackers, in a designated contained area. For additional applicable BMPs refer to the following BMPs: Fueling at Dedicated Stations; Washing and Steam Cleaning Vehicle/Equipment/Building Structures; Loading and Unloading Areas for Liquid or Solid Material; Storage of Liquids in Permanent Above-Ground Tanks; Storage of Liquid, Food Waste, or Dangerous Waste Containers; 2-34 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- Storage or Transfer (Outside) of Solid Raw Materials, By-Products, or Finished Products; Spills of Oil and Hazardous Substances; Illicit Connections to Storm Drains; and other BMPs provided in this chapter. Applicable Treatment BMPs: Contaminated stormwater runoff from vehicle staging and maintenance areas must be conveyed to a sanitary sewer, if allowed by the local sewer authority, or to an API or CP oil and water separator followed by a basic treatment BMP (See Volume applicable filter, or other equivalent oil treatment system. Note that a treatment BMP is applicable for contaminated stormwater. Recommended Additional Operational BMPs: x Consider storing damaged vehicles inside a building or other covered containment, until all liquids are removed. Remove liquids from vehicles retired for scrap. x Clean parts with aqueous detergent based solutions or non-chlorinated solvents such as kerosene or high flash mineral spirits, and/or use wire brushing or sand blasting whenever practicable. Avoid using toxic liquid cleaners such as methylene chloride, 1,1,1-trichloroethane, trichloroethylene or similar chlorinated solvents. Choose cleaning agents that can be recycled. x Inspect all BMPs regularly, particularly after a significant storm. Identify and correct deficiencies to ensure that the BMPs are functioning as intended. x Avoid hosing down work areas. Use dry methods for cleaning leaked fluids. x Recycle greases, used oil, oil filters, antifreeze, cleaning solutions, automotive batteries, hydraulic fluids, transmission fluids, and engine oils (see Appendix IV-C). x Do not mix dissimilar or incompatible waste liquids stored for recycling. February 2005 Volume IV - Source Control BMPs 2-35 ---PAGE BREAK--- BMPs for Maintenance of Stormwater Drainage and Treatment Systems Description of Pollutant Sources: Facilities include roadside catch basins on arterials and within residential areas, conveyance systems, detention facilities such as ponds and vaults, oil and water separators, biofilters, settling basins, infiltration systems, and all other types of stormwater treatment systems presented in Volume V. Roadside catch basins can remove from 5 to 15 percent of the pollutants present in stormwater. When catch basins are about 60 percent full of sediment, they cease removing sediments. Oil and grease, hydrocarbons, debris, heavy metals, sediments and contaminated water are found in catch basins, oil and water separators, settling basins, etc. Pollutant Control Approach: Provide maintenance and cleaning of debris, sediments, and oil from stormwater collection, conveyance, and treatment systems to obtain proper operation. Applicable Operational BMPs: Maintain stormwater treatment facilities according to the O & M procedures presented in Section 4.6 of Volume V in addition to the following BMPs: x Inspect and clean treatment BMPs, conveyance systems, and catch basins as needed, and determine whether improvements in O & M are needed. x repair any deterioration threatening the structural integrity of the facilities. These include replacement of clean-out gates, catch basin lids, and rock in emergency spillways. x Ensure that storm sewer capacities are not exceeded and that heavy sediment discharges to the sewer system are prevented. x Regularly remove debris and sludge from BMPs used for peak-rate control, treatment, etc. and discharge to a sanitary sewer if approved by the sewer authority, or truck to a local or state government approved disposal site. x Clean catch basins when the depth of deposits reaches 60 percent of the sump depth as measured from the bottom of basin to the invert of the lowest pipe into or out of the basin. However, in no case should there be less than six inches clearance from the debris surface to the invert of the lowest pipe. Some catch basins (for example, WSDOT Type 1L basins) may have as little as 12 inches sediment storage below the invert. These catch basins will need more frequent inspection and cleaning to prevent scouring. Where these catch basins are part of a stormwater collection and treatment system, the system owner/operator may choose to concentrate maintenance efforts on control devices as part of a systems approach. 2-40 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- x Clean woody debris in a catch basin as frequently as needed to ensure proper operation of the catchbasin. x Post warning signs; “Dump No Waste - Drains to Ground Water,” “Streams,” “Lakes,” or emboss on or adjacent to all storm drain inlets where practical. x Disposal of sediments and liquids from the catch basins must comply with “Recommendations for Management of Street Wastes” described in Appendix IV-G of this volume. Additional Applicable BMPs: Select additional applicable BMPs from this chapter depending on the pollutant sources and activities conducted at the facility. Those BMPs include: x BMPs for Soil Erosion and Sediment Control at Industrial Sites x BMPs for Storage of Liquid, Food Waste, or Dangerous Waste Containers x BMPs for Spills of Oil and Hazardous Substances x BMPs for Illicit Connections to Storm Drains x BMPs for Urban Streets. February 2005 Volume IV - Source Control BMPs 2-41 ---PAGE BREAK--- BMPs for Manufacturing Activities - Outside Description of Pollutant Sources: Manufacturing pollutant sources include outside process areas, stack emissions, and areas where manufacturing activity has taken place in the past and significant pollutant materials remain and are exposed to stormwater. Pollution Control Approach: Cover and contain outside manufacturing and prevent stormwater run-on and contamination, where feasible. Applicable Operational BMP: x Sweep paved areas regularly, as needed, to prevent contamination of stormwater. Applicable Structural Source Control BMPs: x Alter the activity by eliminating or minimizing the contamination of stormwater. x Enclose the activity (see Figure 2.6): If possible, enclose the manufacturing activity in a building. x Cover the activity and connect floor drains to a sanitary sewer, if approved by the local sewer authority. Berm or slope the floor as needed to prevent drainage of pollutants to outside areas. (Figure 2.7) x Isolate and segregate pollutants as feasible. Convey the segregated pollutants to a sanitary sewer, process treatment or a dead-end sump depending on available methods and applicable permit requirements. Figure 2.6 – Enclose the Activity Figure 2.7 – Cover the Activity 2-42 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- fire department need not be covered. Potential spill/leak conveyance surfaces must be impervious and in good repair.  Placement of a drip pan, or an absorbent pad under each fueling location prior to and during all dispensing operations. The pan (must be liquid tight) and the absorbent pad must have a capacity of 5 gallons. Spills retained in the drip pan or the pad need not be reported.  The handling and operation of fuel transfer hoses and nozzle, drip pan(s), and absorbent pads as needed to prevent spills/leaks of fuel from reaching the ground, storm drains, and receiving waters.  Not extending the fueling hoses across a traffic lane without fluorescent traffic cones, or equivalent devices, conspicuously placed so that all traffic is blocked from crossing the fuel hose.  Removing the fill nozzle and cessation of filling when the automatic shut-off valve engages. Do not allow automatic shutoff fueling nozzles to be locked in the open position.  Not “topping off” the fuel receiving equipment x Provide the driver/operator of the fueling vehicle with:  Adequate flashlights or other mobile lighting to view fill openings with poor accessibility. Consult with local fire department for additional lighting requirements.  Two-way communication with his/her home base. x Train the driver/operator annually in spill prevention and cleanup measures and emergency procedures. Make all employees aware of the significant liability associated with fuel spills. x The fueling operating procedures should be properly signed and dated by the responsible manager, distributed to the operators, retained in the organization files, and made available in the event an authorized government agency requests a review. x Ensure that the local fire department (911) and the appropriate regional office of the Department of Ecology are immediately notified in the event of any spill entering the surface or ground waters. Establish a “call down list” to ensure the rapid and proper notification of management and government officials should any significant amount of product be lost off-site. Keep the list in a protected but readily accessible location in the mobile fueling truck. The “call down list” should also pre-identify spill response contractors available in the area to ensure the rapid removal of significant product spillage into the environment. 2-44 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- x Maintain a minimum of the following spill clean-up materials in all fueling vehicles, that are readily available for use:  Non-water absorbents capable of absorbing 15 gallons of diesel fuel;  A storm drain plug or cover kit;  A non-water absorbent containment boom of a minimum 10 feet in length with a 12-gallon absorbent capacity;  A non-metallic shovel; and,  Two, five-gallon buckets with lids. x Use automatic shutoff nozzles for dispensing the fuel. Replace automatic shut-off nozzles as recommended by the manufacturer. x Maintain and replace equipment on fueling vehicles, particularly hoses and nozzles, at established intervals to prevent failures. Applicable Structural Source Control BMPs: Include the following fuel transfer site components: x Automatic fuel transfer shut-off nozzles; and, x An adequate lighting system at the filling point. February 2005 Volume IV - Source Control BMPs 2-45 ---PAGE BREAK--- BMPs for Parking and Storage of Vehicles and Equipment Description of Pollutant Sources: Public and commercial parking lots such as retail store, fleet vehicle (including rent-a-car lots and car dealerships), equipment sale and rental parking lots, and parking lot driveways, can be sources of toxic hydrocarbons and other organic compounds, oils and greases, metals, and suspended solids caused by the parked vehicles. Pollutant Control Approach: If the parking lot is a high-use site as defined below, provide appropriate oil removal equipment for the contaminated stormwater runoff. Applicable Operational BMPs: x If washing of a parking lot is conducted, discharge the washwater to a sanitary sewer, if allowed by the local sewer authority, or other approved wastewater treatment system, or collect it for off-site disposal. x Do not hose down the area to a storm drain or to a receiving water. Sweep parking lots, storage areas, and driveways, regularly to collect dirt, waste, and debris. Applicable Treatment BMPs: An oil removal system such as an API or CP oil and water separator, catch basin filter, or equivalent BMP, approved by the local jurisdiction, is applicable for parking lots meeting the threshold vehicle traffic intensity level of a high-use site. Vehicle High-Use Sites Establishments subject to a vehicle high-use intensity have been determined to be significant sources of oil contamination of stormwater. Examples of potential high use areas include customer parking lots at fast food stores, grocery stores, taverns, restaurants, large shopping malls, discount warehouse stores, quick-lube shops, and banks. If the PGIS for a high-use site exceeds 5,000 square feet in a threshold discharge area, and oil control BMP from the Oil Control Menu is necessary. A high-use site at a commercial or industrial establishment has one of the following characteristics: (Gaus/King County, 1994) x Is subject to an expected average daily vehicle traffic (ADT) count equal to or greater than 100 vehicles per 1,000 square feet of gross building area: or x Is subject to storage of a fleet of 25 or more diesel vehicles that are over 10 tons gross weight (trucks, buses, trains, heavy equipment, etc.). 2-48 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- BMPs for Railroad Yards Description of Pollutant Sources: Pollutant sources can include drips/leaks of vehicle fluids onto the railroad bed, human waste disposal, litter, locomotive/railcar/equipment cleaning areas, fueling areas, outside material storage areas, the erosion and loss of soil particles from the railroad bed, maintenance and repair activities at railroad terminals, switching yards, and maintenance yards, and herbicides used for vegetation management. Waste materials can include waste oil, solvents, degreasers, antifreeze solutions, radiator flush, acids, brake fluids, soiled rags, oil filters, sulfuric acid and battery sludges, and machine chips with residual machining oil and toxic fluids/solids lost during transit. Potential pollutants include oil and grease, TSS, BOD, organics, pesticides, and metals. Pollutant Control Approach: Apply good housekeeping and preventive maintenance practices to control leaks and spills of liquids in railroad yard areas. Applicable Operational and Structural Source Control BMPs: x Implement the applicable BMPs in this chapter depending on the pollutant generating activities/sources at a railroad yard facility. x Do not allow discharge to outside areas from toilets while a train is in transit. Pumpout facilities should be used to service these units. x Use drip pans at hose/pipe connections during liquid transfer and other leak-prone areas. x During maintenance do not discard debris or waste liquids along the tracks or in railroad yards. Applicable Treatment BMPs: In areas subjected to leaks/spills of oils or other chemicals convey the contaminated stormwater to appropriate treatment such as a sanitary sewer, if approved by the appropriate sewer authority, or, to a CP or API oil/water separator for floating oils, or other treatment, as approved by the local jurisdiction. February 2005 Volume IV - Source Control BMPs 2-49 ---PAGE BREAK--- Description of Pollutant Sources: Industrial activities on soil areas; exposed and disturbed soils; steep grading; etc. can be sources of sediments that can contaminate stormwater runoff. BMPs for Soil Erosion and Sediment Control at Industrial Sites Pollutant Control Approach: Limit the exposure of erodible soil, stabilize or cover erodible soil where necessary to prevent erosion, and/or provide treatment for stormwater contaminated with TSS caused by eroded soil. Applicable BMPs: Cover Practice Options: x Vegetative cover such as grass, trees, shrubs, on erodible soil areas; or, x Covering with mats such as clear plastic, jute, fiber; and/or, x Preservation of natural vegetation including grass, trees, shrubs, and vines, Structural Practice Options: Vegetated swale, dike, silt fence, check dam, gravel filter berm, sedimentation basin, and proper grading. (For design information refer to Volume II, “Standards and Specifications for BMPs”). 2-52 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- BMPs for Spills of Oil and Hazardous Substances Description of Pollutant Sources: Owners or operators of facilities engaged in drilling, producing, gathering, storing, processing, transferring, distributing, refining or consuming oil and/or oil products are required by Federal Law to have a Spill Prevention and Control Plan if the storage capacity of the facility, which is not buried, is 1,320 gallons or more of oil, or any single container with a capacity in excess of 660 gallons and which, due to their location, could reasonably be expected to discharge oil in harmful quantities, as defined in 40 CFR Part 110, into or upon the navigable waters of the United States or adjoining shorelines {40 CFR 112.1 Onshore and offshore facilities, which, due to their location, could not reasonably be expected to discharge oil into or upon the navigable waters of the United States or adjoining shorelines are exempt from these regulations {40 CFR 112.1(1)(i)}. Owners of businesses that produce Dangerous Wastes are also required by State Law to have a spill control plan. These businesses should refer to Appendix IV-D R.6. The federal definition of oil is oil of any kind or any form, including, but not limited to petroleum, fuel oil, sludge, oil refuse, and oil mixed with wastes other than dredged spoil. Pollutant Control Approach: Maintain, update, and implement an oil spill prevention/cleanup plan. Applicable Operational BMPs: The businesses and public agencies identified in Appendix IV-A that are required to prepare and implement an Emergency Spill Cleanup Plan shall implement the following: x Prepare an Emergency Spill Control Plan (SCP), which includes:  A description of the facility including the owner's name and address;  The nature of the activity at the facility;  The general types of chemicals used or stored at the facility;  A site plan showing the location of storage areas for chemicals, the locations of storm drains, the areas draining to them, and the location and description of any devices to stop spills from leaving the site such as positive control valves;  Cleanup procedures;  Notification procedures to be used in the event of a spill, such as notifying key personnel. Agencies such as Ecology, local fire department, Washington State Patrol, and the local Sewer Authority, shall be notified;  The name of the designated person with overall spill cleanup and notification responsibility; February 2005 Volume IV - Source Control BMPs 2-53 ---PAGE BREAK--- x Train key personnel in the implementation of the Emergency SCP. Prepare a summary of the plan and post it at appropriate points in the building, identifying the spill cleanup coordinators, location of cleanup kits, and phone numbers of regulatory agencies to be contacted in the event of a spill; x Update the SCP regularly; x Immediately notify Ecology and the local Sewer Authority if a spill may reach sanitary or storm sewers, ground water, or surface water, in accordance with federal and Ecology spill reporting requirements; x Immediately clean up spills. Do not use emulsifiers for cleanup unless an appropriate disposal method for the resulting oily wastewater is implemented. Absorbent material shall not be washed down a floor drain or storm sewer; and, x Locate emergency spill containment and cleanup kit(s) in high potential spill areas. The contents of the kit shall be appropriate for the type and quantities of chemical liquids stored at the facility. Recommended Additional Operational BMP: Spill kits should include appropriately lined drums, absorbent pads, and granular or powdered materials for neutralizing acids or alkaline liquids where applicable. In fueling areas: absorbent should be packaged in small bags for easy use and small drums should be available for storage of absorbent and/or used absorbent. Spill kits should be deployed in a manner that allows rapid access and use by employees. 2-54 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- BMPs for Storage of Liquid, Food Waste, or Dangerous Waste Containers Description of Pollutant Sources: Steel and plastic drums with volumetric capacities of 55 gallons or less are typically used at industrial facilities for container storage of liquids and powders. The BMPs specified below apply to container(s) located outside a building used for temporary storage of accumulated food wastes, vegetable or animal grease, used oil, liquid feedstock or cleaning chemical, or Dangerous Wastes (liquid or solid) unless the business is permitted by Ecology to store the wastes (Appendix IV-D R.4). Leaks and spills of pollutant materials during handling and storage are the primary sources of pollutants. Oil and grease, acid/alkali pH, BOD, COD are potential pollutant constituents. Pollutant Control Approach: Store containers in impervious containment under a roof or other appropriate cover, or in a building. For roll-containers (for example, dumpsters) that are picked up directly by the collection truck, a filet can be placed on both sides of the curb to facilitate moving the dumpster. If a storage area is to be used on-site for less than 30 days, a portable temporary secondary system like that shown in Figure 2.8 can be used in lieu of a permanent system as described above. Figure 2.8 – Secondary Containment System Applicable Operational BMPs: x Place tight-fitting lids on all containers. x Place drip pans beneath all mounted container taps and at all potential drip and spill locations during filling and unloading of containers. x Inspect container storage areas regularly for corrosion, structural failure, spills, leaks, overfills, and failure of piping systems. Check containers daily for leaks/spills. Replace containers, and replace and tighten bungs in drums as needed. x Businesses accumulating Dangerous Wastes that do not contain free liquids need only to store these wastes in a sloped designated area with February 2005 Volume IV - Source Control BMPs 2-55 ---PAGE BREAK--- the containers elevated or otherwise protected from storm water run- on. x Drums stored in an area where unauthorized persons may gain access must be secured in a manner that prevents accidental spillage, pilferage, or any unauthorized use (see Figure 2.9). Figure 2.9 – Locking System for Drum Lid x If the material is a Dangerous Waste, the business owner must comply with any additional Ecology requirements as specified in Appendix IV-D R.3. x Storage of reactive, ignitable, or flammable liquids must comply with the Uniform Fire Code (Appendix IV-D R.2). x Cover dumpsters, or keep them under cover such as a lean-to, to prevent the entry of stormwater. Replace or repair leaking garbage dumpsters. x Drain dumpsters and/or dumpster pads to sanitary sewer. Keep dumpster lids closed. Install waterproof liners. Applicable Structural Source Control BMPs: x Keep containers with Dangerous Waste, food waste, or other potential pollutant liquids inside a building unless this is impracticable due to site constraints or Uniform Fire Code requirements. x Store containers in a designated area, which is covered, bermed or diked, paved and impervious in order to contain leaks and spills (see Figure 2.10). The secondary containment shall be sloped to drain into a dead-end sump for the collection of leaks and small spills. x For liquid wastes, surround the containers with a dike as illustrated in Figure 2.10. The dike must be of sufficient height to provide a volume of either 10 percent of the total enclosed container volume or 110 percent of the volume contained in the largest container, whichever is greater, or, if a single container, 110 percent of the volume of that container. 2-56 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- Figure 2.10 – Covered and Bermed Containment Area x Where material is temporarily stored in drums, a containment system can be used as illustrated, in lieu of the above system (see Figure 2.8). x Place containers mounted for direct removal of a liquid chemical for use by employees inside a containment area as described above. Use a drip pan during liquid transfer (see Figure 2.11). Figure 2.11 – Mounted Container - with drip pan Applicable Treatment BMP: x For contaminated stormwater in the containment area, connect the sump outlet to a sanitary sewer, if approved by the local Sewer Authority, or to appropriate treatment such as an API or CP oil/water separator, catch basin filter or other appropriate system (see Volume Equip the sump outlet with a normally closed valve to prevent the release of spilled or leaked liquids, especially flammables (compliance with Fire Codes), and dangerous liquids. This valve may be opened only for the conveyance of contaminated stormwater to treatment. Note that a treatment BMP is applicable for contaminated stormwater from drum storage areas. x Another option for discharge of contaminated stormwater is to pump it from a dead-end sump or catchment to a tank truck or other appropriate vehicle for off-site treatment and/or disposal. February 2005 Volume IV - Source Control BMPs 2-57 ---PAGE BREAK--- BMPs for Storage of Liquids in Permanent Above-ground Tanks Description of Pollutant Sources: Above-ground tanks containing liquids (excluding uncontaminated water) may be equipped with a valved drain, vent, pump, and bottom hose connection. They may be heated with steam heat exchangers equipped with steam traps. Leaks and spills can occur at connections and during liquid transfer. Oil and grease, organics, acids, alkalis, and heavy metals in tank water and condensate drainage can also cause stormwater contamination at storage tanks. Pollutant Control Approach: Install secondary containment or a double- walled tank. Slope the containment area to a drain with a sump. Stormwater collected in the containment area may need to be discharged to treatment such as an API or CP oil/water separator, or equivalent BMP. Add safeguards against accidental releases including protective guards around tanks to protect against vehicle or forklift damage, and tagging valves to reduce human error. Tank water and condensate discharges are process wastewater that may need an NPDES Permit. Applicable Operational BMPs: x Inspect the tank containment areas regularly to identify problem components such as fittings, pipe connections, and valves, for leaks/spills, cracks, corrosion, etc. x Place adequately sized drip pans beneath all mounted taps and drip/spill locations during filling/unloading of tanks. Valved drain tubing may be needed in mounted drip pans. x Sweep and clean the tank storage area regularly, if paved. x Replace or repair tanks that are leaking, corroded, or otherwise deteriorating. x All installations shall comply with the Uniform Fire Code (Appendix IV-D R.2) and the National Electric Code. Applicable Structural Source Control BMPs: x Locate permanent tanks in impervious (Portland cement concrete or equivalent) secondary containment surrounded by dikes as illustrated in Figure 2.12, or UL Approved double-walled. The dike must be of sufficient height to provide a containment volume of either 10 percent of the total enclosed tank volume or 110 percent of the volume contained in the largest tank, whichever is greater, or, if a single tank, 110 percent of the volume of that tank. x Slope the secondary containment to drain to a dead-end sump (optional), or equivalent, for the collection of small spills. x Include a tank overfill protection system to minimize the risk of spillage during loading. 2-58 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- Figure 2.12 – Above-ground Tank Storage Applicable Treatment BMPs: x If the tank containment area is uncovered, equip the outlet from the spill-containment sump with a shutoff valve, which is normally closed and may be opened, manually or automatically, only to convey contaminated stormwater to approved treatment or disposal, or to convey uncontaminated stormwater to a storm drain. Evidence of contamination can include the presence of visible sheen, color, or turbidity in the runoff, or existing or historical operational problems at the facility. Simple pH measurements with litmus or pH paper can be used for areas subject to acid or alkaline contamination. Note the applicable treatment BMP for stormwater from petroleum tank farms. x At petroleum tank farms, convey stormwater contaminated with floating oil or debris in the contained area through an API or CP-type oil/water separator (Volume V, Treatment BMPs), or other approved treatment prior to discharge to storm drain or surface water. February 2005 Volume IV - Source Control BMPs 2-59 ---PAGE BREAK--- BMPs for Storage or Transfer (Outside) of Solid Raw Materials, By-Products, or Finished Products Description of Pollutant Sources: Solid raw materials, by-products, or products such as gravel, sand, salts, topsoil, compost, logs, sawdust, wood chips, lumber and other building materials, concrete, and metal products sometimes are typically stored outside in large piles, stacks, etc. at commercial or industrial establishments. Contact of outside bulk materials with stormwater can cause leachate, and erosion of the stored materials. Contaminants include TSS, BOD, organics, and dissolved salts (sodium, calcium, and magnesium chloride, etc). Pollutant Control Approach: Provide impervious containment with berms, dikes, etc. and/or cover to prevent run-on and discharge of leachate pollutant(s) and TSS. Applicable Operational BMP: Do not hose down the contained stockpile area to a storm drain or a conveyance to a storm drain or to a receiving water. Applicable Structural Source Control BMP Options: Choose one or more of the source control BMP options listed below for stockpiles greater than 5 cubic yards of erodible or water soluble materials such as soil, road deicing salts, compost, unwashed sand and gravel, sawdust, etc. Also included are outside storage areas for solid materials such as logs, bark, lumber, metal products, etc. x Store in a building or paved and bermed covered area as shown in Figure 2.13, or; Figure 2.13 – Covered Storage Area for Bulk Solids (include berm if needed) x Place temporary plastic sheeting (polyethylene, polypropylene, hypalon, or equivalent) over the material as illustrated (see Figure 2.14), or; 2-60 Volume IV - Source Control BMPs February 2005 ---PAGE BREAK--- Figure 2.14 – Material Covered with Plastic Sheeting x Pave the area and install a stormwater drainage system. Place curbs or berms along the perimeter of the area to prevent the run-on of unconta- minated stormwater and to collect and convey runoff to treatment. Slope the paved area in a manner that minimizes the contact between stormwater pooling) and leachable materials in compost, logs, bark, wood chips, etc. x For large stockpiles that cannot be covered, implement containment practices at the perimeter of the site and at any catch basins as needed to prevent erosion and discharge of the stockpiled material offsite or to a storm drain. Ensure that contaminated stormwater is not discharged directly to catch basins without conveying through a treatment BMP. Applicable Treatment BMP: Convey contaminated stormwater from the stockpile area to a wet pond, wet vault, settling basin, media filter, or other appropriate treatment system depending on the contamination. Recommended Additional Operational BMPs: x Maintain drainage areas in and around storage of solid materials with a minimum slope of 1.5 percent to prevent pooling and minimize leachate formation. Areas should be sloped to drain stormwater to the perimeter where it can be collected, or to internal drainage “alleyways” where material is not stockpiled. x Sweep paved storage areas regularly for collection and disposal of loose solid materials. x If and when feasible, collect and recycle water-soluble materials (leachates) to the stockpile. x Stock cleanup materials, such as brooms, dustpans, and vacuum sweepers near the storage area. February 2005 Volume IV - Source Control BMPs 2-61 ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report APPENDIX 4-B SPILL CONTROL PLAN ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 5 MINIMUM REQUIREMENT #4 PRESERVATION OF NATURAL DRAINAGE SYSTEMS AND OUTFALLS ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report NATURAL DRAINAGE COURSE DESCRIPTION The natural drainage course for the entire site is to drain directly to Evans Creek and the adjacent wetland. With this in mind, the entire site is considered to be within a single threshold discharge area. We are proposing treating flows from a high intensity use site to “enhanced treatment” standards and percolate flows into the ground after treatment. The facility is designed to infiltrate the full 50-year design storm event without overtopping. Flowrates above this rate will discharge to the nearby wetlands through an emergency overflow structure. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 6 MINIMUM REQUIREMENT #5 ON-SITE STORMWATER MANAGEMENT ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Existing Site Hydrology Stormwater runoff from the project site currently flows thru a series of pipes, catch basins, and overland flow into an underground wetvault for treatment. The vault discharges to a structure with a down-turned elbow to provide additional oil-water separation, then into a pump chamber manhole where flows are pressurized up into a 5000 gallon holding tank. A second pump discharges from the holding tank to the existing 1.5-inch force main, which crosses the creek into a permitted class-5 injection well (infiltration trench). Developed Site Hydrology The proposed drainage improvements will relocate the existing above-ground tank outside of the 25’ Evans Creek buffer. The tank will also be taken off-line, and a new pump will be installed inside the underground treatment vault, with capacity to convey the peak 50-year design flowrate. The pump will discharge to a 4-inch ductile iron force main, which will convey runoff to a new bioinfiltration pond on the north side of Evans Creek. The pond will provide enhanced treatment, and is designed to infiltrate the full 50-year design storm. Performance Standards Flow Control and Stormwater Quality elements are subject to the requirements of the 2005 Washington State Department of Ecology Stormwater Management Manual for the Puget Sound Basin. WWHM3 Continuous Stormwater Modeling software was used to calculate tributary flowrates for pump sizing and pond detention volume ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 7 MINIMUM REQUIREMENT #6 RUNOFF TREATMENT ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report PROJECT RUNOFF TREATMENT DESIGN OVERVIEW The existing project site includes an underground wetvault, which utilizes several flow control elbows and oil booms. As has been discussed with the City of Redmond, this system is not conventional so is very difficult to provide calculations justifying its functional ability. It is also noteworthy that oil/water separation systems are designed based on droplet size and viscosity. Pollutants on this site consist of diesel fuel, lubricating oil, hydraulic fluids, etc., all in very low concentrations and all with varying characteristics. Infiltration is feasible at the project site, and will be utilized to be consistent with the Treatment Facility Selection Flow Chart in the 2005 DOE Stormwater Management Manual for Western Washington. The project proposes a bioinfiltration facility of the existing underground vault, which is designed to accommodate the full 50-year design storm event. This will allow the existing vault to serve as a pre- settling basin and oil-water separation device. In addition to the pre-settling and oil/water separation benefits, the existing vault will provide a flow control benefit, by introducing a lag in travel time between the tributary basin and detention facility. Additional discussion of this benefit is provided in Section 8. INFILTRATION/DETENTION SYSTEM PERFORMANCE CRITERIA Per the 2005 DOE manual, section 3.3.4: The proposed infiltration facility has been designed to infiltrate the full 50-yr design storm, which exceeds the required performance criteria. With this in mind, calculation of the minimum required treatment flows was not necessary. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 8 MINIMUM REQUIREMENT #7 FLOW CONTROL ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Existing Site Hydrology Stormwater runoff from the project site currently flows thru a series of pipes, catch basins, and overland flow into an underground wet vault for treatment. From the wet vault, water continues into an oil water separator, and then into a pump chamber manhole where flows are pressurized up into a 5000 gallon holding tank, then pressurized again thru a force main out of the holding tank and across the creek into a permitted class 5 injection well (infiltration trench). Developed Site Hydrology Proposed drainage improvements include relocation of the existing above ground tank (currently inside the 25’ natural Evans Creek buffer) to be outside the buffer. The tank will remain connected to the underground vault, to draw water for use by the property owner, but will be taken off-line from the stormwater conveyance system. A new pump will be installed in the chamber of the existing vault. This pump will discharge to a new 4-inch ductile iron force main which will convey runoff north of Evans Creek, to a new bioinfiltration pond. The pond is intended to provide enhanced treatment in addition to a flow control benefit. The pond has been designed to detain and infiltrate the full 50-year design storm event. The storm drainage model used for the bioinfiltration pond design does not account for the proposed pump, since the pump could eventually be replaced in the future. This also provides a conservative estimate of system performance, because it does not take advantage of the lag in travel time that occurs as the existing vault is filled up and pumped out. The sizing calculations for the pond were performed using the open pond node in WWHM 3, with the infiltration feature activated. The pond design is done using a long term infiltration rate of 1.0 inches per hour, and a safety factor of 2, this infiltration rate corresponds to the DOE rate for 6” of topsoil in the pond. Pond sizing calculations are provided in Appendix 8-A. The proposed pump has been sized to convey the full 50-year peak design flowrate. Design calculations for the pump have been included in Appendix 8-B. Performance Standards Flow Control and Stormwater Quality elements are subject to the requirements of the 2005 Washington State Department of Ecology Stormwater Management Manual for the Puget Sound Basin. The modeling software used for both water quality treatment design flows and volumes, and detention volume calculations and release rates is version 3.0 of the WWHM3 Continuous Stormwater Modeling Software. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report APPENDIX 8-A FLOW CONTROL DESIGN CALCULATIONS ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Existing Site Conditions Developed Site Conditions ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Stage/Storage/Discharge Calculations The table below provides a tabulation of the bioinfiltration pond characteristics used for flow control design. The data in the table is derived as follows: Column 1: Contour Elevation – Measured at the bottom of the pond at each 0.5-ft interval Column 2: Contour Area – Measured from AutoCAD design drawing Column 3: Contour Area – Converted from sq. ft. to acres for WWHM input Column 4: Incremental Volume – Volume between previous contour area and current contour area Column 5: Cumulative Volume – Total storage volume below the current contour Column 6: Discharge Rate – Calculated discharge rate through overflow riser, using the overflow Spillway design equations provided in the DOE and King County stormwater manuals. Column 7: Infiltration Rate – Area of the pond floor multiplied by the design infiltration rate (0.5 in/hr) Contour Contour Contour Incremental Cumulative Discharge Infiltration Elevation Area Area Volume Volume Rate Rate (ft) (ft2) (ac) (ac-ft) (ac-ft) (cfs) (cfs) 60.8 7,404 0.17 0.00 0.00 0 0.09 61.0 7,625 0.18 0.04 0.04 0 0.09 61.5 8,180 0.19 0.09 0.13 0 0.09 62.0 8,753 0.20 0.10 0.23 0 0.09 62.5 9,343 0.21 0.10 0.33 0 0.09 63.0 9,950 0.23 0.11 0.44 0 0.09 63.5 10,574 0.24 0.12 0.56 0 0.09 64.0 11,215 0.26 0.13 0.69 13.77 0.09 64.5 11,868 0.27 0.13 0.82 38.96 0.09 ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Western Washington Hydrology Model PROJECT REPORT Project Name: All Wood Site Address: City : Redmond Report Date : 2/26/2013 Gage : Seatac Data Start : 1948/10/01 Data End : 1998/09/30 Precip Scale: 1.00 WWHM3 Version: PREDEVELOPED LAND USE Name : Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres C, Forest, Flat 2.09 Impervious Land Use Acres Element Flows To: Surface Interflow Groundwater MITIGATED LAND USE Name : Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres Impervious Land Use Acres ROADS FLAT 1.8 POND 0.29 Element Flows To: Surface Interflow Groundwater SSD Table 1, SSD Table 1, ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Name : SSD Table 1 Depth: 3.7ft. Element Flows To: Outlet 1 Outlet 2 SSD Table Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Infilt(cfs) 0.000 0.170 0.000 0.000 0.090 0.200 0.180 0.040 0.000 0.090 0.700 0.190 0.130 0.000 0.090 1.200 0.200 0.230 0.000 0.090 1.700 0.210 0.330 0.000 0.090 2.200 0.230 0.440 0.000 0.090 2.700 0.240 0.560 0.000 0.090 3.200 0.260 0.690 13.77 0.090 3.700 0.270 0.820 38.96 0.090 ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.0526 5 year 0.081507 10 year 0.097171 25 year 0.113092 50 year 0.122545 100 year 0.130313 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.560544 5 year 0.682941 10 year 0.762176 25 year 0.861155 50 year 0.934444 100 year 1.007591 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.060 [PHONE REDACTED] 0.103 0.000 1952 0.131 0.000 1953 0.040 0.000 1954 0.031 0.000 1955 0.046 0.000 1956 0.081 0.000 1957 0.066 0.000 1958 0.051 0.000 1959 0.057 0.000 1960 0.047 0.000 ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report 1961 0.081 0.000 1962 0.048 0.000 1963 0.028 0.000 1964 0.038 0.000 1965 0.047 0.000 1966 0.035 0.000 1967 0.036 0.000 1968 0.078 0.000 1969 0.048 0.000 1970 0.047 0.000 1971 0.036 0.000 1972 0.034 0.000 1973 0.095 0.000 1974 0.043 0.000 1975 0.045 0.000 1976 0.065 0.000 1977 0.043 0.000 1978 0.004 0.000 1979 0.036 0.000 1980 0.022 0.000 1981 0.064 0.000 1982 0.034 0.000 1983 0.059 0.000 1984 0.058 0.000 1985 0.037 0.000 1986 0.020 0.000 1987 0.102 0.000 1988 0.085 0.000 1989 0.031 0.000 1990 0.020 0.000 1991 0.135 0.000 1992 0.119 0.122 1993 0.039 0.000 1994 0.045 0.000 1995 0.011 0.000 1996 0.064 0.000 1997 0.124 0.000 1998 0.114 0.355 1999 0.023 0.000 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.1347 735.6720 2 0.1314 0.3550 3 0.1236 0.1225 4 0.1190 0.0000 5 0.1142 0.0000 6 0.1032 0.0000 7 0.1016 0.0000 8 0.0955 0.0000 9 0.0848 0.0000 10 0.0814 0.0000 11 0.0806 0.0000 12 0.0777 0.0000 13 0.0662 0.0000 14 0.0651 0.0000 ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report 15 0.0637 0.0000 16 0.0636 0.0000 17 0.0602 0.0000 18 0.0593 0.0000 19 0.0577 0.0000 20 0.0569 0.0000 21 0.0509 0.0000 22 0.0477 0.0000 23 0.0475 0.0000 24 0.0475 0.0000 25 0.0471 0.0000 26 0.0470 0.0000 27 0.0459 0.0000 28 0.0454 0.0000 29 0.0448 0.0000 30 0.0434 0.0000 31 0.0426 0.0000 32 0.0404 0.0000 33 0.0387 0.0000 34 0.0376 0.0000 35 0.0371 0.0000 36 0.0365 0.0000 37 0.0360 0.0000 38 0.0357 0.0000 39 0.0350 0.0000 40 0.0343 0.0000 41 0.0337 0.0000 42 0.0312 0.0000 43 0.0310 0.0000 44 0.0279 0.0000 45 0.0233 0.0000 46 0.0220 0.0000 47 0.0201 0.0000 48 0.0197 0.0000 49 0.0113 0.0000 50 0.0043 0.0000 POC #1 The Facility PASSED. Flow(CFS) Predev Dev Percentage Pass/Fail 0.0263 3892 15 0 Pass 0.0273 3599 15 0 Pass 0.0282 3365 12 0 Pass 0.0292 3145 12 0 Pass 0.0302 2933 12 0 Pass 0.0312 2733 12 0 Pass 0.0321 2560 12 0 Pass 0.0331 2390 12 0 Pass 0.0341 2226 12 0 Pass 0.0350 2085 12 0 Pass 0.0360 1959 12 0 Pass 0.0370 1849 12 0 Pass 0.0380 1746 12 0 Pass 0.0389 1658 12 0 Pass ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report 0.0399 1568 12 0 Pass 0.0409 1473 12 0 Pass 0.0419 1390 12 0 Pass 0.0428 1308 12 0 Pass 0.0438 1245 12 0 Pass 0.0448 1183 12 1 Pass 0.0457 1113 12 1 Pass 0.0467 1056 12 1 Pass 0.0477 1008 12 1 Pass 0.0487 949 12 1 Pass 0.0496 912 12 1 Pass 0.0506 874 12 1 Pass 0.0516 825 12 1 Pass 0.0525 782 12 1 Pass 0.0535 751 12 1 Pass 0.0545 715 12 1 Pass 0.0555 681 12 1 Pass 0.0564 658 12 1 Pass 0.0574 622 12 1 Pass 0.0584 602 12 1 Pass 0.0594 571 12 2 Pass 0.0603 549 12 2 Pass 0.0613 521 12 2 Pass 0.0623 492 12 2 Pass 0.0632 468 12 2 Pass 0.0642 443 12 2 Pass 0.0652 423 12 2 Pass 0.0662 402 12 2 Pass 0.0671 383 12 3 Pass 0.0681 365 12 3 Pass 0.0691 350 12 3 Pass 0.0700 338 12 3 Pass 0.0710 318 12 3 Pass 0.0720 302 12 3 Pass 0.0730 283 12 4 Pass 0.0739 275 12 4 Pass 0.0749 259 12 4 Pass 0.0759 244 12 4 Pass 0.0769 234 12 5 Pass 0.0778 222 12 5 Pass 0.0788 212 12 5 Pass 0.0798 204 12 5 Pass 0.0807 198 12 6 Pass 0.0817 187 12 6 Pass 0.0827 183 12 6 Pass 0.0837 177 12 6 Pass 0.0846 168 12 7 Pass 0.0856 161 12 7 Pass 0.0866 155 12 7 Pass 0.0875 154 12 7 Pass 0.0885 149 12 8 Pass 0.0895 143 12 8 Pass 0.0905 137 12 8 Pass 0.0914 131 12 9 Pass 0.0924 124 12 9 Pass 0.0934 119 12 10 Pass 0.0944 110 11 10 Pass ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report 0.0953 106 11 10 Pass 0.0963 102 11 10 Pass 0.0973 92 11 11 Pass 0.0982 86 11 12 Pass 0.0992 82 11 13 Pass 0.1002 71 11 15 Pass 0.1012 67 11 16 Pass 0.1021 63 11 17 Pass 0.1031 58 11 18 Pass 0.1041 54 9 16 Pass 0.1050 50 9 18 Pass 0.1060 48 9 18 Pass 0.1070 46 9 19 Pass 0.1080 43 9 20 Pass 0.1089 37 9 24 Pass 0.1099 34 9 26 Pass 0.1109 32 9 28 Pass 0.1119 27 9 33 Pass 0.1128 25 9 36 Pass 0.1138 23 9 39 Pass 0.1148 20 9 45 Pass 0.1157 19 9 47 Pass 0.1167 18 9 50 Pass 0.1177 18 9 50 Pass 0.1187 15 9 60 Pass 0.1196 13 9 69 Pass 0.1206 13 9 69 Pass 0.1216 10 9 90 Pass 0.1225 10 8 80 Pass Water Quality BMP Flow and Volume for POC 1. On-line facility volume: 0.0739 acre-feet On-line facility target flow: 0.01 cfs. Adjusted for 15 min: 0.2675 cfs. Off-line facility target flow: 0.1816 cfs. Adjusted for 15 min: 0.2052 cfs. Perlnd and Changes No changes have been made. 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. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report The following flow frequency table has been copied and pasted from WWHM to compare the pre- developed flowrates to the discharge rates from the bioinfiltration pond. The pre-developed flows are reported in the “0501” column, and the discharge rates from the proposed pond are reported in the “0801” column. The purpose of this table is to verify that the pond can infiltrate the full 50-year design storm event. Flow Frequency Flow(CFS) 0501 0801 2 Year = 0.0526 0.0000 5 Year = 0.0815 0.0000 10 Year = 0.0972 0.0000 25 Year = 0.1131 0.0000 50 Year = 0.1225 0.0000 100 Year = 0.1303 0.0000 Note that the discharge rates for all storm events are reported as 0.0000 cfs. This column does not include infiltration, only flows that are discharged through the overflow riser. The absence of any flow through the overflow riser indicates that all stormwater is infiltrated. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report APPENDIX 8-B PUMP SIZING CALCULATIONS ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Design Flowrate Design Flowrate = 0.86 cfs [50-yr peak flow, per WWHM Calculation] 386 gpm [50-yr peak flow, converted to gpm] Static Head Start Elevation (Z1) = 51.50 ft [Elevation at bottom of vault] End Elevation (Z2) = 62.70 ft [Maximum water surface elevation of pond] Static Head (hS) = 11.20 ft [Calculated, Z2 - Z1] Friction Head (Using Hazen-Williams Equation for Head Loss in Pipes) Pipe Diameter = 4 in [Force main diameter, per plan] Pipe Length = 566 ft [Force main length, per plan] Friction Coef (Ch) = 120 [Hazen-Williams Coef. for small-diam pipe] Pipe Area = 0.26 ft [Cross-sectional area of pipe, A = pD2/4] Flow Velocity = 3.28 ft [Full-flow pipe velocity, V = Q/A] Friction Head (hf) = 7.92 ft Fitting/Transition Head Fitting Qty Kb hL 90° Bend 0 0.35 0.00 ft 45° Bend 5 0.1 0.00 ft Total Transition Head = 0.00 ft Total Dynamic Head Static Head = 11.20 [from above] Friction Head = 7.92 [from above] Transition Head = 0.00 [from above] Total Dynamic Head = 19.12 ft ---PAGE BREAK--- C O N T R A C T O R P U M P S & G E N E R A T O R S Electric Submersible Pumps • Engine Driven Pumps • Generators • Accessories BUILT FOR WORK w w w . t s u r u m i p u m p . c o m ---PAGE BREAK--- 13 Electric Submersible Pumps 6 3 5 4 7 2 1 Designed to withstand the most demanding conditions found in the construction, aggregate and mining markets. Tsurumi KTZ Series dewatering pump easily converts between high head and high volume performance with a simple change of impeller and wear plate. Wide range of sizes for any job. KTZ Series Features Circle Thermal Motor Protector: Protects against, overheating over amperage & run-dry. Anti-Wicking Block: Prevents water incursion due to capillary wicking, should the power cable be damaged or the end submerged. Oil Lifter: Lubrication of the seal faces down to 1/3 of normal oil level and extends seal life by ten times—uses no additional power. Dual Inside Mechanical Seal with Silicon Carbide Faces: Provides longer operational life of any seal available. Lip Seal Protector: Protects mechanical seal from abrasive particles. High Chrome Iron Semi-Open Impeller: Resists wear by abrasive particles. Field Adjustable/Replaceable, Ductile Iron Wear Plate: Resists wear by abrasive particles, and is easily adjusted to maintain pump performance. 1 2 3 4 5 6 7 KTZ THREE PHASE DEWATERING PUMPS 60Hz 2 Pole 2-15HP Capacity (gal/min) Total Head (ft) Certified by Intertek Testing Service to UL and CSA standards for submersible construction pumps. ---PAGE BREAK--- 25 Electric Submersible Pumps Specifications KTZ21.5 KTZ22.2 KTZ23.7 KTZ31.5 KTZ32.2 KTZ33.7 KTZ35.5 KTZ43.7 KTZ45.5 KTZ47.5 KTZ411 KTZ67.5 KTZ611 Max. Capacity (GPM) 106 132 143 180 203 219 260 386 428 349 377 549 645 Max. Head (ft.) 75 100 115 47 67 102 125 61 79 137 167 102 107 Solid Diameter (inches) Impeller Type Impeller Material Casing Material Wear Plate Material Shaft Seal - Type / Material Seal Lubricant - Type Seal Lubricant - Amount (ounces) 25.0 25.0 40.6 25.0 25.0 40.6 37.2 40.6 37.2 25.7 25.7 25.7 25.7 Seal Protection Discharge Connection Motor Output (hp) 2 3 5 2 3 5 7.5 5 7.5 10 15 10 15 Phase Voltage Amperage - Rated Current 6.2-6.0/ 3.1/2.3 9.4-9.0/ 4.5/3.5 15.0-13.6/ 6.8/5.3 6.2-6.0/ 3.1/2.3 9.4-9.0/ 4.5/3.5 15.0-13.6/ 6.8/5.3 21.0-20.0/ 10.0/7.9 15.0-13.6/ 6.8/5.3 21.0-20.0/ 10.0/7.9 28.8-26.6/ 13.3/10.4 40.0-37.6/ 18.6/14.9 28.8-26.6/ 13.3/10.4 40.0-37.6/ 18.6/14.9 Amperage - Starting Current 44/22/16 46/38/28 120/60/43 44/22/16 46/38/28 120/60/43 170/85/62 120/60/43 170/85/62 236/118/ 85 310/155/ 120 236/118/ 85 310/155/ 120 Type Bearings Insulation Class Motor Protection (Built-In) Plug Configuration (Nema) Cable - #of Conductors x AWG 4Cx16AWG 4Cx16AWG 4Cx14AWG 4Cx16AWG 4Cx16AWG 4Cx14AWG 4Cx12AWG 4Cx14AWG 4Cx12AWG 4Cx10AWG 4Cx8AWG 4Cx10AWG 4Cx8AWG Standard Cable Length (ft.) Max. Cable Length (ft.) 130 (230V) 610 (460V) 670 (575V) 90 (230V) 400 (460V) 440 (575V) 90 (230V) 450 (460V) 460 (575V) 130 (230V) 610 (460V) 670 (575V) 90 (230V) 400 (460V) 440 (575V) 90 (230V) 450 (460V) 460 (575V) 110 (230V) 540 (460V) 590 (575V) 90 (230V) 450 (460V) 460 (575V) 110 (230V) 540 (460V) 590 (575V) 130 (230V) 650 (460V) 690 (575V) 130 (230V) 650 (460V) 690 (575V) 130 (230V) 650 (460V) 690 (575V) 130 (230V) 650 (460V) 690 (575V) Recommended Generator Capacity 8800 12400 19100 8800 12400 19100 27600 19100 27600 38300 53700 38300 53700 Optional Float Switch Diameter (inches) 9 1/4 9 1/4 11 1/8 9 1/4 9 1/4 11 1/8 12 1/16 11 1/8 12 1/16 13 14 11/16 13 14 11/16 Height (inches) 21 9/16 22 3/8 25 1/16 21 9/16 22 3/8 25 1/16 27 1/16 25 1/16 27 1/16 28 1/8 31 3/4 28 1/8 or 30 11/16 31 3/4 or 30 3/16 Continuous Running Water Level (in.) 4 3/4 4 3/4 5 7/8 4 3/4 4 3/4 5 7/8 5 7/8 5 7/8 5 7/8 7 1/2 7 1/2 7 1/2 7 1/2 Pump Weight (lbs.) 66 75 139 66 75 139 181 139 181 231 293 236 300 Cast Iron F Circle Thermal Protector No Plug Water Resistant Pumps 5/16 13/16 50 Ductile Cast Iron Double inside mechanical seal with Silicon Carbide SAE 10W/20W or Turbine Oil (ISO VG32) Lip Seal and Oil Lifter (Oil Lifter is patented by Tsurumi Pump) Double shielded, permanentary lubricated Continuous duty, Air filled, 3600RPM, 60Hz 208-230 / 460 / 575 4" NPT Coupling is optional) Three Semi-Open High Chrome DIMENSION N/A FLUID PUMP MOTOR 2" NPT Coupling 3" NPT Coupling 4" NPT Coupling KTZ Series ---PAGE BREAK--- 31 Available for the HS2.4S, the Residue Kit allows pumping of residual water down to 0.4 inches. The Sand Kit can be added to the NK Series to suspend sand and prevent sand lock. Sand Kit Model: K15-SK Control Panels For NK, KTZ, LH, and LHW Series MANUAL CONTROL PANEL INCLUDES: • Manual Simplex Operation. • Nema 4X, Lockable Fiberglass Enclosure. • IEC Contactor. • Hand/Off Selector Switch. • UL Listed. • Cable Grips In Control Panel. AUTOMATIC CONTROL PANEL INCLUDES: • Automatic or Manual Simplex Operation. • Nema 4X, Lockable Fiberglass Enclosure. • IEC Rated Magnetic Contactor. • Hand/Off Auto Selector Switch. • UL Listed. • Includes 20 Ft. Mechanical Float Switches. • Cable Grips In Control Panel. Inverter Panels are available for LHW and KTZ series Single Phase operation. Residue Kit Model: HS-RK Wheel Kit & Lifting Bail For All Generators, Gas Engine Pumps: Wheel Kit PGWK-200 / PGWK-11K and Lifting Bail PGLB-1 Heavy-duty and easy to install our wheel kits and lifting bails fit all of Tsurumi Generators. Wheel Kit PGWK-200 for TPG3 Series Generator & Gas Engine Pumps Wheel Kit PGWK-11K for TPG-11000HDXE Lifting Bail PGLB-1 ---PAGE BREAK--- Anti-Wicking Cable Entrance: Maximum protection against water incursion through the cable entry. • Molded Cable Boot or Cable Protection Tube - extends cable bending radius, prevents abrading, and reduces fatigue. • Cable Gland - provides 360 degree compression of cable boot, protection tube or cable bush for a water tight fit. • Anti-Wicking Block - window cuts on conductor insulation expose strands to molded rubber or epoxy to prove water wicking through the strands and entering the motor providing protection even if the cable insulation is cut. Circle Thermal Protector (CTP) - for pumps with 1-10HP : 3-Pole protector connects to each winding of the motor and reacts to excessive heat and amperage. Automatic reset at safe temperature to restart the motor. No motor protection circuit required in starter or control panel. Dual Inside, Silicon Carbide Mechanical Seals: Isolation of mechanical seals in an oil chamber provides a clean, non-corrosive and abrasion free lubricating environment to prevent spring failure due to corrosion or abrasion and bottom seal failure due to loss of cooling during dry-run conditions. AIR AIR OIL OIL ROTATION Oil Flow Oil Flow Oil Lifter (Patented): Tsurumi’s exclusive Oil Lifter encloses the mechanical seal and uses the centrifugal force generated by the rotating shaft and seal to pump oil to the upper seal faces. Upper and lower seal faces are positively lubricated even when extremely low oil levels exist, as experienced after long periods of extended operation. V-Ring: V-Ring is mounted at the top of the impeller and is brought in close contact to the bottom of the mechanical seal by the internal pressure of the pump casing. This V-Ring acts as a dust seal to prevent fine abrasive particles in the pumping fluid from reaching the mechanical seal. High-Performance Motor: Dry type, squirrel-cage, induction motor, housed in a watertight casing, conforms to either insulation class B or E, or F. In both of these classes, all standard pumps can be used in ambient temperature up to 104°F (40°C). SUPERIOR DESIGN & TECHNOLOGY For Sales, Service, and Specifications, call: Your Dealer TSURUMI (AMERICA), INC. 1625 Fullerton Court Glendale Heights, IL 60139 Tel: 1-[PHONE REDACTED] (Toll-Free) 1-[PHONE REDACTED] Fax: 1-[PHONE REDACTED] 1-888-TSURUMI (878-7864) MAY12 TSURUMI (AMERICA), INC. WEST 6216 West 9790 South West Jordan, UT 84081 Tel: 1-[PHONE REDACTED] (Toll-Free) 1-[PHONE REDACTED] Fax: 1-[PHONE REDACTED] Visit our website: www.tsurumipump.com ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 9 MINIMUM REQUIREMENT #8 WETLANDS PROTECTION ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report PROJECT OVERVIEW We are hydrating the wetlands as they are being hydrated now, and consistent with the conditions of the Shoreline Permit. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 10 MINIMUM REQUIREMENT #9 BASIN/WATERSHED PLANNING ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report BASIN/WATERSHED PLANNING We are hydrating the wetlands as they are being hydrated now, and consistent with the conditions of the Shoreline Permit. There are no other applicable basin/watershed plans for the project. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 11 MINIMUM REQUIREMENT #10 OPERATION AND MAINTENANCE ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Operation and Maintenance Section: ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Maintenance Component Defect Conditions When Maintenance Is Needed Results Expected When Maintenance Is Performed Beaver Dams Dam results in change or function of the facility. Facility is returned to design function. (Coordinate trapping of beavers and removal of dams with appropriate permitting agencies) Insects When insects such as wasps and hornets interfere with maintenance activities. Insects destroyed or removed from site. Apply insecticides in compliance with adopted IPM policies Tree Growth and Hazard Trees Tree growth does not allow maintenance access or interferes with maintenance activity slope mowing, silt removal, vactoring, or equipment movements). If trees are not interfering with access or maintenance, do not remove If dead, diseased, or dying trees are identified (Use a certified Arborist to determine health of tree or removal requirements) Trees do not hinder maintenance activities. Harvested trees should be recycled into mulch or other beneficial uses alders for firewood). Remove hazard Trees Side Slopes of Pond Erosion Eroded damage over 2 inches deep where cause of damage is still present or where there is potential for continued erosion. Any erosion observed on a compacted berm embankment. Slopes should be stabilized using appropriate erosion control measure(s); e.g., rock reinforcement, planting of grass, compaction. If erosion is occurring on compacted berms a licensed civil engineer should be consulted to resolve source of erosion. Storage Area Sediment Accumulated sediment that exceeds 10% of the designed pond depth unless otherwise specified or affects inletting or outletting condition of the facility. Sediment cleaned out to designed pond shape and depth; pond reseeded if necessary to control erosion. Liner (If Applicable) Liner is visible and has more than three 1/4-inch holes in it. Liner repaired or replaced. Liner is fully covered. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Maintenance Component Defect Conditions When Maintenance Is Needed Results Expected When Maintenance Is Performed Pond Berms (Dikes) Settlements Any part of berm which has settled 4 inches lower than the design elevation. If settlement is apparent, measure berm to determine amount of settlement. Settling can be an indication of more severe problems with the berm or outlet works. A licensed civil engineer should be consulted to determine the source of the settlement. Dike is built back to the design elevation. Piping Discernable water flow through pond berm. Ongoing erosion with potential for erosion to continue. (Recommend a Goethechnical engineer be called in to inspect and evaluate condition and recommend repair of condition. Piping eliminated. Erosion potential resolved. Emergency Overflow/ Spillway and Berms over 4 feet in height. Tree Growth Tree growth on emergency spillways creates blockage problems and may cause failure of the berm due to uncontrolled overtopping. Tree growth on berms over 4 feet in height may lead to piping through the berm which could lead to failure of the berm. Trees should be removed. If root system is small (base less than 4 inches) the root system may be left in place. Otherwise the roots should be removed and the berm restored. A licensed civil engineer should be consulted for proper berm/spillway restoration. Piping Discernable water flow through pond berm. Ongoing erosion with potential for erosion to continue. (Recommend a Goethechnical engineer be called in to inspect and evaluate condition and recommend repair of condition. Piping eliminated. Erosion potential resolved. Emergency Overflow/ Spillway Emergency Overflow/ Spillway Only one layer of rock exists above native soil in area five square feet or larger, or any exposure of native soil at the top of out flow path of spillway. (Rip-rap on inside slopes need not be replaced.) Rocks and pad depth are restored to design standards. Erosion See “Side Slopes of Pond” No. 4 – Control Structure/Flow Restrictor Maintenance Component Defect Condition When Maintenance is Needed Results Expected When Maintenance is Performed General Trash and Debris (Includes Sediment) Material exceeds 25% of sump depth or 1 foot below orifice plate. Control structure orifice is not blocked. All trash and debris removed. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Structural Damage Structure is not securely attached to manhole wall. Structure securely attached to wall and outlet pipe. Structure is not in upright position (allow up to 10% from plumb). Structure in correct position. Connections to outlet pipe are not watertight and show signs of rust. Connections to outlet pipe are water tight; structure repaired or replaced and works as designed. Any holes--other than designed holes--in the structure. Structure has no holes other than designed holes. Cleanout Gate Damaged or Missing Cleanout gate is not watertight or is missing. Gate is watertight and works as designed. Gate cannot be moved up and down by one maintenance person. Gate moves up and down easily and is watertight. Chain/rod leading to gate is missing or damaged. Chain is in place and works as designed. Gate is rusted over 50% of its surface area. Gate is repaired or replaced to meet design standards. Orifice Plate Damaged or Missing Control device is not working properly due to missing, out of place, or bent orifice plate. Plate is in place and works as designed. Obstructions Any trash, debris, sediment, or vegetation blocking the plate. Plate is free of all obstructions and works as designed. Overflow Pipe Obstructions Any trash or debris blocking (or having the potential of blocking) the overflow pipe. Pipe is free of all obstructions and works as designed. Manhole See “Closed Detention Systems” (No. See “Closed Detention Systems” (No. See “Closed Detention Systems” (No. Catch Basin See “Catch Basins” (No. See “Catch Basins” (No. See “Catch Basins” (No. No. 5 – Catch Basins Maintenance Component Defect Conditions When Maintenance is Needed Results Expected When Maintenance is performed General Trash & Debris Trash or debris which is located immediately in front of the catch basin opening or is blocking inletting capacity of the basin by more than 10%. No Trash or debris located immediately in front of catch basin or on grate opening. Trash or debris (in the basin) that exceeds 60 percent of the sump depth as measured from the bottom of basin to invert of the lowest pipe into or out of the basin, but in no case less than a minimum of six inches clearance from the debris surface to the invert of the lowest pipe. No trash or debris in the catch basin. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Trash or debris in any inlet or outlet pipe blocking more than 1/3 of its height. Inlet and outlet pipes free of trash or debris. Dead animals or vegetation that could generate odors that could cause complaints or dangerous gases methane). No dead animals or vegetation present within the catch basin. Sediment Sediment (in the basin) that exceeds 60 percent of the sump depth as measured from the bottom of basin to invert of the lowest pipe into or out of the basin, but in no case less than a minimum of 6 inches clearance from the sediment surface to the invert of the lowest pipe. No sediment in the catch basin Structure Damage to Frame and/or Top Slab Top slab has holes larger than 2 square inches or cracks wider than 1/4 inch (Intent is to make sure no material is running into basin). Top slab is free of holes and cracks. Frame not sitting flush on top slab, i.e., separation of more than 3/4 inch of the frame from the top slab. Frame not securely attached Frame is sitting flush on the riser rings or top slab and firmly attached. Fractures or Cracks in Basin Walls/ Bottom Maintenance person judges that structure is unsound. Basin replaced or repaired to design standards. Grout fillet has separated or cracked wider than 1/2 inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. Pipe is regrouted and secure at basin wall. Settlement/ Misalignment If failure of basin has created a safety, function, or design problem. Basin replaced or repaired to design standards. Vegetation Vegetation growing across and blocking more than 10% of the basin opening. No vegetation blocking opening to basin. Vegetation growing in inlet/outlet pipe joints that is more than six inches tall and less than six inches apart. No vegetation or root growth present. ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Maintenance Component Defect Conditions When Maintenance is Needed Results Expected When Maintenance is performed Contamination and Pollution See "Detention Ponds" (No. No pollution present. Catch Basin Cover Cover Not in Place Cover is missing or only partially in place. Any open catch basin requires maintenance. Catch basin cover is closed Locking Mechanism Not Working Mechanism cannot be opened by one maintenance person with proper tools. Bolts into frame have less than 1/2 inch of thread. Mechanism opens with proper tools. Cover Difficult to Remove One maintenance person cannot remove lid after applying normal lifting pressure. (Intent is keep cover from sealing off access to maintenance.) Cover can be removed by one maintenance person. Ladder Ladder Rungs Unsafe Ladder is unsafe due to missing rungs, not securely attached to basin wall, misalignment, rust, cracks, or sharp edges. Ladder meets design standards and allows maintenance person safe access. Metal Grates (If Applicable) Grate opening Unsafe Grate with opening wider than 7/8 inch. Grate opening meets design standards. Trash and Debris Trash and debris that is blocking more than 20% of grate surface inletting capacity. Grate free of trash and debris. Damaged or Missing. Grate missing or broken member(s) of the grate. Grate is in place and meets design standards. Maintenance Components Defect Condition When Maintenance is Needed Results Expected When Maintenance is Performed General Trash and Debris Trash or debris that is plugging more than 20% of the openings in the barrier. Barrier cleared to design flow capacity. Metal Damaged/ Missing Bars. Bars are bent out of shape more than 3 inches. Bars in place with no bends more than 3/4 inch. Bars are missing or entire barrier missing. Bars in place according to design. Bars are loose and rust is causing 50% deterioration to any part of barrier. Barrier replaced or repaired to design standards. Inlet/Outlet Pipe Debris barrier missing or not attached to pipe Barrier firmly attached to pipe No. 5 – Catch Basins ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Maintenance Component Defect Conditions When Maintenance Is Needed Results Expected When Maintenance Is Performed General Trash & Debris See "Detention Ponds" (No. See "Detention Ponds" (No. Poisonous/Noxious Vegetation See "Detention Ponds" (No. See "Detention Ponds" (No. Contaminants and Pollution See "Detention Ponds" (No. See "Detention Ponds" (No. Rodent Holes See "Detention Ponds" (No. See "Detention Ponds" (No. 1) Storage Area Sediment Water ponding in infiltration pond after rainfall ceases and appropriate time allowed for infiltration. (A percolation test pit or test of facility indicates facility is only working at 90% of its designed capabilities. If two inches or more sediment is present, remove). Sediment is removed and/or facility is cleaned so that infiltration system works according to design. Filter Bags (if applicable) Filled with Sediment and Debris Sediment and debris fill bag more than 1/2 full. Filter bag is replaced or system is redesigned. Rock Filters Sediment and Debris By visual inspection, little or no water flows through filter during heavy rain storms. Gravel in rock filter is replaced. Side Slopes of Pond Erosion See "Detention Ponds" (No. See "Detention Ponds" (No. Emergency Overflow Spillway and Berms over 4 feet in height. Tree Growth See "Detention Ponds" (No. See "Detention Ponds" (No. Piping See "Detention Ponds" (No. See "Detention Ponds" (No. Emergency Overflow Spillway Rock Missing See "Detention Ponds" (No. See "Detention Ponds" (No. Erosion See "Detention Ponds" (No. See "Detention Ponds" (No. Pre-settling Ponds and Vaults Facility or sump filled with Sediment and/or debris 6" or designed sediment trap depth of sediment. Sediment is removed. No. 2 – Infiltration ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report Maintenance Component Defect Condition When Maintenance is Needed Results Expected When Maintenance is Performed General Trash/Debris Accumulation Trash and debris accumulated in vault, pipe or inlet/outlet (includes floatables and non- floatables). Remove trash and debris from vault. Sediment Accumulation in Vault Sediment accumulation in vault bottom exceeds the depth of the sediment zone plus 6-inches. Remove sediment from vault. Damaged Pipes Inlet/outlet piping damaged or broken and in need of repair. Pipe repaired and/or replaced. Access Cover Damaged/Not Working Cover cannot be opened or removed, especially by one person. Pipe repaired or replaced to proper working specifications. Ventilation Ventilation area blocked or plugged. Blocking material removed or cleared from ventilation area. A specified % of the vault surface area must provide ventilation to the vault interior (see design specifications). Vault Structure Damage - Includes Cracks in Walls Bottom, Damage to Frame and/or Top Slab Maintenance/inspection personnel determine that the vault is not structurally sound. Vault replaced or repairs made so that vault meets design specifications and is structurally sound. Cracks wider than 1/2-inch at the joint of any inlet/outlet pipe or evidence of soil particles entering through the cracks. Vault repaired so that no cracks exist wider than 1/4-inch at the joint of the inlet/outlet pipe. Baffles Baffles corroding, cracking, warping and/or showing signs of failure as determined by maintenance/inspection staff. Baffles repaired or replaced to specifications. Access Ladder Damage Ladder is corroded or deteriorated, not functioning properly, not attached to structure wall, missing rungs, has cracks and/or misaligned. Confined space warning sign missing. Ladder replaced or repaired to specifications, and is safe to use as determined by inspection personnel. Replace sign warning of confined space entry requirements. Ladder and entry notification complies with OSHA standards. No. 12 – Wetvaults ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report SECTION 12 SPECIAL REPORTS AND STUDIES ---PAGE BREAK--- Stormwater Pollution Prevention Plan All Wood Recycling Technical Information Report APPENDIX 12-A GEOTECHNICAL REPORT ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK---