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19-074-RPT-CSWPPP-2025.01.06 (7529)Construction Stormwater General Permit Stormwater Pollution Prevention Plan (SWPPP) for Deutscher – Yelm Commercial Prepared for: The Washington State Department of Ecology Southwest Regional Office Permittee / Owner Developer Operator / Contractor Marijke Deutscher TBD TBD 15142 Berry Valley Road, Yelm, WA 98597 Certified Erosion and Sediment Control Lead (CESCL) Name Organization Contact Phone Number TBD TBD TBD SWPPP Prepared By Name Organization Contact Phone Number Ahmad Kamyab Hatton Godat Pantier, Inc. (360) 943-1599 SWPPP Preparation Date January 6, 2025 Project Construction Dates Activity / Phase Start Date End Date Permit Spring 2025 Fall 2026 P a g e | 1 Table of Contents 1 Project Information .............................................................................................................. 4 1.1 Existing Conditions ...................................................................................................... 4 1.2 Proposed Construction Activities .................................................................................. 4 2 Construction Stormwater Best Management Practices (BMPs) ........................................... 6 2.1 The 13 Elements .......................................................................................................... 6 2.1.1 Element 1: Preserve Vegetation / Mark Clearing Limits ........................................ 6 2.1.2 Element 2: Establish Construction Access ............................................................ 6 2.1.3 Element 3: Control Flow Rates ............................................................................. 7 2.1.4 Element 4: Install Sediment Controls .................................................................... 7 2.1.5 Element 5: Stabilize Soils ..................................................................................... 8 2.1.6 Element 6: Protect Slopes..................................................................................... 9 2.1.7 Element 7: Protect Drain Inlets ............................................................................. 9 2.1.8 Element 8: Stabilize Channels and Outlets ..........................................................10 2.1.9 Element 9: Control Pollutants ...............................................................................10 2.1.10 Element 10: Control Dewatering ..........................................................................12 2.1.11 Element 11: Maintain BMPs .................................................................................12 2.1.12 Element 12: Manage the Project ..........................................................................13 2.1.13 Element 13: Protect Low Impact Development (LID) BMPs .................................15 3 Pollution Prevention Team .................................................................................................16 4 Monitoring and Sampling Requirements ............................................................................17 4.1 Site Inspection ............................................................................................................17 4.2 Stormwater Quality Sampling ......................................................................................17 4.2.1 Turbidity Sampling ...............................................................................................17 4.2.2 pH Sampling ........................................................................................................19 5 Discharges to 303(d) or Total Maximum Daily Load (TMDL) Waterbodies .........................19 5.1 303(d) Listed Waterbodies ..........................................................................................19 5.2 TMDL Waterbodies .....................................................................................................19 6 Reporting and Record Keeping ..........................................................................................20 6.1 Record Keeping ..........................................................................................................20 6.1.1 Site Log Book ......................................................................................................20 6.1.2 Records Retention ...............................................................................................20 6.1.3 Updating the SWPPP ...........................................................................................20 6.2 Reporting ....................................................................................................................20 6.2.1 Discharge Monitoring Reports ..............................................................................20 6.2.2 Notification of Noncompliance ..............................................................................21 P a g e | 2 List of Tables Table 1 – pH-Modifying Sources ...............................................................................................11 Table 2 – Team Information ......................................................................................................16 Table 3 – Turbidity Sampling Method ........................................................................................17 Table 4 – pH Sampling Method .................................................................................................19 List of Appendices Appendix/Glossary A. Site Map B. BMP Detail C. Correspondence D. Site Inspection Form E. Construction Stormwater General Permit (CSWGP) P a g e | 3 List of Acronyms and Abbreviations Acronym / Abbreviation Explanation 303(d) Section of the Clean Water Act pertaining to Impaired Waterbodies BFO Bellingham Field Office of the Department of Ecology BMP(s) Best Management Practice(s) CESCL Certified Erosion and Sediment Control Lead CO2 Carbon Dioxide CRO Central Regional Office of the Department of Ecology CSWGP Construction Stormwater General Permit CWA Clean Water Act DMR Discharge Monitoring Report DO Dissolved Oxygen Ecology Washington State Department of Ecology EPA United States Environmental Protection Agency ERO Eastern Regional Office of the Department of Ecology ERTS Environmental Report Tracking System ESC Erosion and Sediment Control GULD General Use Level Designation NPDES National Pollutant Discharge Elimination System NTU Nephelometric Turbidity Units NWRO Northwest Regional Office of the Department of Ecology pH Power of Hydrogen RCW Revised Code of Washington SPCC Spill Prevention, Control, and Countermeasure su Standard Units SWMMEW Stormwater Management Manual for Eastern Washington SWMMWW Stormwater Management Manual for Western Washington SWPPP Stormwater Pollution Prevention Plan TESC Temporary Erosion and Sediment Control SWRO Southwest Regional Office of the Department of Ecology TMDL Total Maximum Daily Load VFO Vancouver Field Office of the Department of Ecology WAC Washington Administrative Code WSDOT Washington Department of Transportation WWHM Western Washington Hydrology Model P a g e | 4 1 Project Information Project/Site Name: Deutscher – Yelm Commercial Street/Location: 15152 Berry Valley Road City: Yelm State: WA Zip code: 98597 Subdivision: N/A Receiving waterbody: Thompson Creek 1.1 Existing Conditions Total acreage (including support activities such as off-site equipment staging yards, material storage areas, borrow areas). Total acreage: 5.36 Disturbed acreage: 2.85 Existing structures: Day Care Building Landscape topography: The site is generally flat, with slopes ranging from 1% to 3%. Drainage patterns: In the current condition stormwater runoff in undeveloped areas sheet flow on-site and infiltrate through native soils. The majority of the project surrounding areas are developed and there is no off-site stormwater runoff to the property. Existing Vegetation: The site Phase 2 area are cleared previously for construction, and it is covered with native grass. Critical Areas (wetlands, streams, high erosion risk, steep or difficult to stabilize slopes): The site is located within category I Critical Aquifer Recharge Area and is in the ten-year time of travel zone for a Group A well owned by the City of Yelm. List of known impairments for 303(d) listed or Total Maximum Daily Load (TMDL) for the receiving waterbody: N/A 1.2 Proposed Construction Activities Description of site development (example: subdivision): Commercial buildings Description of construction activities (example: site preparation, demolition, excavation): Clearing, grubbing, installation of new utilities, parking lot, stormwater facilities, and landscaping. Description of site drainage including flow from and onto adjacent properties. Must be consistent with Site Map in Appendix A: Stormwater runoff for the entire site was designed and constructed with Phase 1 “Yelm Day Care” construction. Runoff from Phase 2 roof areas will be connected to 2 infiltration trenches for 100% infiltration onsite and runoff from paved parking areas as well as sidewalks will be connected to the existing infiltration pond for 100% infiltration. Description of final stabilization (example: extent of revegetation, paving, landscaping): At project completion, the property will contain 3 commercial buildings, paved parking areas, sidewalks, landscaping areas, associated utilities. P a g e | 5 Contaminated Site Information: Proposed activities regarding contaminated soils or groundwater (example: on-site treatment system, authorized sanitary sewer discharge): N/A P a g e | 6 2 Construction Stormwater Best Management Practices (BMPs) The SWPPP is a living document reflecting current conditions and changes throughout the life of the project. These changes may be informal (i.e., hand-written notes and deletions). Update the SWPPP when the CESCL has noted a deficiency in BMPs or deviation from original design. 2.1 The 13 Elements 2.1.1 Element 1: Preserve Vegetation / Mark Clearing Limits To protect adjacent properties and to reduce the area of soil exposed during construction, the limits of construction will be clearly marked before land-disturbing activities begin. Trees that are to be preserved 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 Fence (BMP C103) Alternate BMPs for marking clearing limits are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B after the first sign that existing BMPs are ineffective or failing. 2.1.2 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 street sweeping and street cleaning shall be employed to prevent sediment from entering state waters. The specific BMPs related to establishing construction access that will be used on this project include: • Construction Road/Parking Area (BMP C107) • Existing private road will be used as construction access The contractor shall install stabilized construction entrances at the locations and per the details shown on the approved Temporary Erosion and Sediment Control Plans. Alternate BMPs for establishing construction access are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B after the first sign that existing BMPs are ineffective or failing. P a g e | 7 2.1.3 Element 3: Control Flow Rates In order to protect the properties and waterways downstream of the project site, stormwater discharges from the site will be controlled. The specific BMPs for flow control that shall be used on this project include: • Silt Fence (BMP C233) • Temporary Sediment Trap (BMP C240) Alternate flow control BMPs are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B 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 downstream erosion, or where necessary to meet local agency stormwater discharge requirements (e.g. discharge to combined sewer systems). Will you construct stormwater retention and/or detention facilities? Yes No Will you use permanent infiltration ponds or other low impact development (example: rain gardens, bio- retention, porous pavement) to control flow during construction? Yes No 2.1.4 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) • Temporary Sediment Trap (BMP C240) Install Filter Fabric Fencing/Silt Fencing at locations shown and per the details and notes on the approved Temporary Erosion and Sediment Control Plans. In addition, sediment will be removed from paved areas in and adjacent to construction work areas manually or using mechanical sweepers, as needed, to minimize tracking of sediments on vehicle tires away from the site and to minimize washoff of sediments from adjacent streets in runoff. Alternate sediment control BMPs are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will P a g e | 8 promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B after the first sign that existing BMPs are ineffective or failing. 2.1.5 Element 5: Stabilize Soils Exposed and unworked soils shall be stabilized with the application of effective BMPs to prevent erosion throughout the life of the project. The specific BMPs for soil stabilization that shall be used on this project include: • Temporary and Permanent Seeding (BMP C120) • Mulching (BMP C121) • Dust Control (BMP C140) The project site is located west of the Cascade Mountain Crest. From October 1 through April 30, no soils shall remain exposed and unworked for more than 2 days. From May 1 to September 30, no soils shall remain exposed and unworked for more than 7 days. Soils shall be stabilized at the end of the shift before a holiday or weekend if needed based on the weather forecast. These stabilization requirements apply to all soils onsite, whether at final grade or not. The local permitting authority may adjust these time limits if it can be shown that a development site’s erosion and runoff potential justifies a different standard. 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 the transportation of sediment from the construction site to receiving waters will be prevented. In general, cut and fill slopes will be stabilized as soon as possible and soil stockpiles will be temporarily covered with plastic sheeting or seeded and mulched. 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. Alternate soil stabilization BMPs are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B after the first sign that existing BMPs are ineffective or failing. West of the Cascade Mountains Crest Season Dates Number of Days Soils Can be Left Exposed During the Dry Season May 1 – September 30 7 days During the Wet Season October 1 – April 30 2 days Anticipated project dates: Start date: April 2025 End date: April 2026 Will you construct during the wet season? Yes No P a g e | 9 2.1.6 Element 6: Protect Slopes All cut and fill slopes will be designed, constructed, and protected in a manner that minimizes erosion. The following specific BMPs will be used to protect slopes for this project: • Temporary and Permanent Seeding (BMP C120) • Mulching (BMP C121) All slopes where grading occurs or where vegetation has been removed shall be seeded per the notes and details in the approved Temporary Erosion and Sediment Control Plans and in BMP C120. In no case shall soils remain unworked and unstabilized for more than 7 days during the dry season (May 1 to September 30) or more than 2 days during the wet season (October 1 to April 30). Alternate slope protection BMPs are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B after the first sign that existing BMPs are ineffective or failing. Will steep slopes be present at the site during construction? Yes No 2.1.7 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. The following inlet protection measures will be applied on this project: • Storm Drain Inlet Protection (BMP C220) o Drop Inlet Protection – Catch Basin Filters Inlet protection is the last component of a treatment train and protection of drain inlets include additional sediment and erosion control measures. Inlet protection devices will be cleaned (or removed and replaced), when sediment has filled the device by one third (1/3) or as specified by the manufacturer. Inlets will be inspected weekly at a minimum and daily during storm events. Alternate inlet protection BMPs are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B after the first sign that existing BMPs are ineffective or failing. P a g e | 10 2.1.8 Element 8: Stabilize Channels and Outlets Provide stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent stream banks, slopes, and downstream reaches, will be installed at the outlets of all conveyance systems. Where site runoff is to be conveyed in channels or discharged to a stream or some other natural discharge point, efforts will be taken to prevent downstream erosion. The specific BMPs for channel and outlet stabilization that shall be used on this project include: 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 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 downstream reaches shall be provided at the outlets of all conveyance systems. 2.1.9 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. BMPs to be implemented to control specific sources of pollutants are discussed below. Will maintenance, fueling, and/or repair of heavy equipment and vehicles occur on-site? Yes No Maintenance, fueling, and/or repair of heavy equipment and vehicles required to occur on-site shall follow the requirements listed below. If the contractor chooses to store fueling tanks or petroleum product storage containers onsite, they will amend this SWPPP to provide total volume of fuel stored onsite, the capacity of the second containment for each tank, and provide a Spill Prevention, Control, and Countermeasures (SPCC) Plan which complies with Federal regulations of the Clean Water Act (CWA). 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. • 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. Will wheel wash or tire bath system BMPs be used during construction? Yes No Will pH-modifying sources be present on-site? Yes No P a g e | 11 Table 1 – pH-Modifying Sources None Bulk cement Cement kiln dust Fly ash Other cementitious materials New concrete washing or curing waters Waste streams generated from concrete grinding and sawing Exposed aggregate processes Dewatering concrete vaults Concrete pumping and mixer washout waters Recycled concrete Recycled concrete stockpiles Other (i.e., calcium lignosulfate) [please describe: ] Demolition: • N/A 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) Concrete trucks must not be washed out onto the ground, or into storm drains, open ditches, streets, or streams. Excess concrete must not be dumped on-site, except in designated concrete washout areas with appropriate BMPs installed. Will uncontaminated water from water-only based shaft drilling for construction of building, road, and bridge foundations be infiltrated provided the wastewater is managed in a way that prohibits discharge to surface waters? Yes No Sanitary wastewater: • Portable sanitation facilities will be firmly secured, regularly maintained, and emptied when necessary. Solid Waste: • Solid waste will be stored in secure, clearly marked containers. Other: • Other BMPs will be administered as necessary to address any additional pollutant sources onsite. P a g e | 12 2.1.10 Element 10: Control Dewatering This project does not propose dewatering during construction. Should dewatering be necessary, all dewatering water from open cut excavation, tunneling, foundation work, trench, or underground vaults shall be discharged into a controlled conveyance system prior to discharge to a sediment trap or sediment pond. Channels will be stabilized per Element #8. Highly turbid dewatering water from soils known or suspected to be contaminated, or from use of construction equipment, will require additional monitoring and treatment as required for the specific pollutants based on the receiving waters into which the discharge is occurring. Such monitoring is the responsibility of the contractor. However, the dewatering of soils known to be free of contamination will trigger BMPs to trap sediment and reduce turbidity. At a minimum, geotextile fabric socks/bags/cells will be used to filter this material. Other BMPs to be used for sediment trapping and turbidity reduction include the following: • Concrete Handling (BMP C151) • Temporary Sediment Trap (BMP C240) • Use of a sedimentation bag, with outfall to a ditch or swale for small volumes of localized dewatering Alternate dewatering control BMPs are included in Appendix B 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 E). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater Permit (as provided in Appendix E), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix B after the first sign that existing BMPs are ineffective or failing. The following BMPs are to be used to control dewatering: 2.1.11 Element 11: Maintain BMPs All temporary and permanent Erosion and Sediment Control (ESC) BMPs shall be maintained and repaired as needed to ensure continued performance of their intended function. Maintenance and repair shall be conducted in accordance with each particular BMP specification (see Volume II of the SWMMWW or Chapter 7 of the SWMMEW). Visual monitoring of all BMPs installed at the site will be conducted at least once every calendar week and within 24 hours of any stormwater or non-stormwater discharge from the site. If the site becomes inactive and is temporarily stabilized, the inspection frequency may be reduced to once every calendar month. All temporary ESC BMPs shall be removed within 30 days after final site stabilization is achieved or after the temporary BMPs are no longer needed. Trapped sediment shall be stabilized on-site or removed. Disturbed soil resulting from removal of either BMPs or vegetation shall be permanently stabilized. Additionally, protection must be provided for all BMPs installed for the permanent control of stormwater from sediment and compaction. BMPs that are to remain in place following completion of construction shall be examined and restored to full operating condition. If sediment enters these BMPs during P a g e | 13 construction, the sediment shall be removed and the facility shall be returned to conditions specified in the construction documents. This element will be addressed by: • Certified Erosion and Sediment Control Lead (BMP C160) 2.1.12 Element 12: Manage the Project The project will be managed based on the following principles: • Projects will be phased to the maximum extent practicable and seasonal work limitations will be taken into account (BMP C161) • Inspection and monitoring: o Inspection, maintenance and repair of all BMPs will occur as needed to ensure performance of their intended function. o Site inspections and monitoring will be conducted in accordance with Special Condition S4 of the CSWGP. Sampling locations are indicated on the Site Map. Sampling station(s) are located in accordance with applicable requirements of the CSWGP. • Maintain an updated SWPPP. o The SWPPP will be updated, maintained, and implemented in accordance with Special Conditions S3, S4, and S9 of the CSWGP. As site work progresses the SWPPP will be modified routinely to reflect changing site conditions. The SWPPP will be reviewed monthly to ensure the content is current. Erosion and sediment control BMPs for this project have been designed based on the following principles: • Design the project to fit the existing topography, soils, and drainage patterns. • Emphasize erosion control rather than sediment control. • Minimize the extent and duration of the area exposed. • Keep runoff velocities low. • Retain sediment on site. • Thoroughly monitor site and maintain all ESC measures. • Schedule major earthwork during the dry season. In addition, project management will incorporate the key components listed below: As this project site is located west of the Cascade Mountain Crest, the project will be managed according to the following key project components: Phasing of Construction • The construction project is being phased to the extent practicable in order to prevent soil erosion, and, to the maximum extent possible, the transport of sediment from the site during construction. • Revegetation of exposed areas and maintenance of that vegetation shall be an integral part of the clearing activities during each phase of construction, per the Scheduling BMP (C 162). P a g e | 14 • 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: o Site conditions including existing vegetative coverage, slope, soil type, and proximity to receiving waters; and o Limitations on activities and the extent of disturbed areas; and o Proposed erosion and sediment control measures. • Based on the information provided and/or local weather conditions, the local permitting authority may expand or restrict the seasonal limitation on site disturbance. • The following activities are exempt from the seasonal clearing and grading limitations: o Routine maintenance and necessary repair of erosion and sediment control BMPs; o Routine maintenance of public facilities or existing utility structures that do not expose the soil or result in the removal of the vegetative cover to soil; and o Activities where there is 100 percent infiltration of surface water runoff within the site in approved and installed erosion and sediment control facilities. Coordination with Utilities and Other Jurisdictions • Care has been taken to coordinate with utilities, other construction projects, and the local jurisdiction in preparing this SWPPP and scheduling the construction work. Inspection and Monitoring • All BMPs shall be inspected, maintained, and repaired as needed to assure continued performance of their intended function. Site inspections shall be conducted by a person who is knowledgeable in the principles and practices of erosion and sediment control. This person has the necessary skills to: o Assess the site conditions and construction activities that could impact the quality of stormwater, and o Assess the effectiveness of erosion and sediment control measures used to control the quality of stormwater discharges. • A Certified Erosion and Sediment Control Lead shall be on-site or on-call at all times. (BMP C160) • Whenever inspection and/or monitoring reveals that the BMPs identified in this SWPPP are inadequate, due to the actual discharge of or potential to discharge a significant amount of any pollutant, appropriate BMPs or design changes shall be implemented as soon as possible. Maintaining an Updated Construction SWPPP • This SWPPP shall be retained on-site or within reasonable access to the site. • The SWPPP shall be modified whenever there is a change in the design, construction, operation, or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the state. • The SWPPP shall be modified if, during inspections or investigations conducted by the owner/operator, or the applicable local or state regulatory authority, it is determined that the SWPPP is ineffective in eliminating or significantly minimizing pollutants in stormwater discharges P a g e | 15 from the site. The SWPPP shall be modified as necessary to include additional or modified BMPs designed to correct problems identified. Revisions to the SWPPP shall be completed within seven (7) days following the inspection. 2.1.13 Element 13: Protect Low Impact Development (LID) BMPs Low Impact Development (LID) for this site includes landscape areas. Protect all completed LID BMPs from construction traffic, mark lawn/landscaping areas with High Visibility Plastic or Metal Fencing. Provide buffe zones to ensure construction activities remain off the completed LID. P a g e | 16 3 Pollution Prevention Team Table 2 – Team Information Title Name(s) Phone Number Certified Erosion and Sediment Control Lead (CESCL) TBD TBD Resident Engineer Hatton Godat Pantier – Chloe McIntyre (360) 943-1599 Emergency Ecology Contact Report-a-Spill Hotline (360) 407-6300 Emergency Permittee/ Owner Contact Marijke Deutscher (360) 402-6871 Non-Emergency Owner Contact Marijke Deutscher (360) 402-6871 Monitoring Personnel TBD TBD Ecology Regional Office Southwest Regional Office (360) 407-6300 P a g e | 17 4 Monitoring and Sampling Requirements Monitoring includes visual inspection, sampling for water quality parameters of concern, and documentation of the inspection and sampling findings in a site log book. A site log book will be maintained for all on-site construction activities and will include: • A record of the implementation of the SWPPP and other permit requirements • Site inspections • Stormwater sampling data For convenience, the inspection form and water quality monitoring forms included in this SWPPP include the required information for the site log book. This SWPPP may function as the site log book if desired, or the forms may be separated and included in a separate site log book. However, if separated, the site log book must be maintained on-site or within reasonable access to the site and be made available upon request to Ecology or the local jurisdiction. Numeric effluent limits may be required for certain discharges to 303(d) listed waterbodies. See CSWGP Special Condition S8 and Section 5 of this template. 4.1 Site Inspection Site inspections will be conducted at least once every calendar week and within 24 hours following any discharge from the site. For sites that are temporarily stabilized and inactive, the required frequency is reduced to once per calendar month. The discharge point(s) are indicated on the Site Map (see Appendix A) and in accordance with the applicable requirements of the CSWGP. 4.2 Stormwater Quality Sampling 4.2.1 Turbidity Sampling Requirements include calibrated turbidity meter or transparency tube to sample site discharges for compliance with the CSWGP. Sampling will be conducted at all discharge points at least once per calendar week. Method for sampling turbidity: Table 3 – Turbidity Sampling Method Turbidity Meter/Turbidimeter (required for disturbances 5 acres or greater in size) Transparency Tube (option for disturbances less than 1 acre and up to 5 acres in size) The benchmark for turbidity value is 25 nephelometric turbidity units (NTU) and a transparency less than 33 centimeters. If the discharge’s turbidity is 26 to 249 NTU or the transparency is less than 33 cm but equal to or greater than 6 cm, the following steps will be conducted: 1. Review the SWPPP for compliance with Special Condition S9. Make appropriate revisions within 7 days of the date the discharge exceeded the benchmark. P a g e | 18 2. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible. Address the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period. 3. Document BMP implementation and maintenance in the site log book. If the turbidity exceeds 250 NTU or the transparency is 6 cm or less at any time, the following steps will be conducted: 1. Telephone or submit an electronic report to the applicable Ecology Region’s Environmental Report Tracking System (ERTS) within 24 hours. • Southwest Region (Clallam, Clark, Cowlitz, Grays Harbor, Jefferson, Lewis, Mason, Pacific, Pierce, Skamania, Thurston, Wahkiakum,): (360) 407-6300 or http://www.ecy.wa.gov/programs/spills/forms/nerts_online/SWRO_nerts_online.html 2. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible. Address the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period 3. Document BMP implementation and maintenance in the site log book. 4. Continue to sample discharges daily until one of the following is true: • Turbidity is 25 NTU (or lower). • Transparency is 33 cm (or greater). • Compliance with the water quality limit for turbidity is achieved. o 1 - 5 NTU over background turbidity, if background is less than 50 NTU o 1% - 10% over background turbidity, if background is 50 NTU or greater • The discharge stops or is eliminated. P a g e | 19 4.2.2 pH Sampling pH monitoring is required for “Significant concrete work” (i.e., greater than 1000 cubic yards poured concrete over the life of the project). The use of recycled concrete or engineered soils (soil amendments including but not limited to Portland cement-treated base [CTB], cement kiln dust [CKD] or fly ash) also requires pH monitoring. For significant concrete work, pH sampling will start the first day concrete is poured and continue until it is cured, typically three (3) weeks after the last pour. For engineered soils and recycled concrete, pH sampling begins when engineered soils or recycled concrete are first exposed to precipitation and continues until the area is fully stabilized. If the measured pH is 8.5 or greater, the following measures will be taken: 1. Prevent high pH water from entering storm sewer systems or surface water. 2. Adjust or neutralize the high pH water to the range of 6.5 to 8.5 su using appropriate technology such as carbon dioxide (CO2) sparging (liquid or dry ice). 3. Written approval will be obtained from Ecology prior to the use of chemical treatment other than CO2 sparging or dry ice. Method for sampling pH: Table 4 – pH Sampling Method pH meter pH test kit Wide range pH indicator paper 5 Discharges to 303(d) or Total Maximum Daily Load (TMDL) Waterbodies 5.1 303(d) Listed Waterbodies Is the receiving water 303(d) (Category 5) listed for turbidity, fine sediment, phosphorus, or pH? Yes No 5.2 TMDL Waterbodies Waste Load Allocation for CWSGP discharges: N/A Discharges to TMDL receiving waterbodies will meet in-stream water quality criteria at the point of discharge.