8920 EVERGREEN WAY THE RESERVE 2025-07-25

CITY OF EVERETT STORMWATER MANAGEMENT MANUAL sewer,authorization must be obtained from the City's Industrial Pretreatment Program at(425) 257-8874. 7. If a holding tank is used for storage of washwater,the contents must be pumped out before it is full and disposed of appropriately to a sanitary sewer or wastewater treatment system. 8. A cover must be placed over a designated wash area to keep rain from falling on dirty equipment and producing contaminated runoff. A1.3 Washing, Pressure Washing, and Steam Cleaning of Vehicles, Equipment, or Building Structures Description of Pollutant Sources: Vehicles,aircraft,vessels,carpets,industrial equipment,and large buildings may be commercially cleaned with low or high pressure water or steam. This includes frequent "charity"car washes at gas stations and commercial parking lots. The cleaning can include hand washing,scrubbing,sanding, etc. Washwater from cleaning activities can contain oil and grease, suspended solids,heavy metals, soluble organics, soaps,and detergents that can contaminate stormwater. Pollutant Control Approach: The preferred approach is to cover and/or contain the cleaning activity,or conduct the activity inside a building,in order to prevent the pollution of stormwater. Washwater must be conveyed to a sanitary sewer after approval by the City's Industrial Pretreatment Program,temporarily stored before proper disposal,or recycled—with no discharge to a storm drain or surface water unless an NPDES permit is obtained from Ecology for the discharge. Washwater may be discharged to the ground after proper treatment in accordance with Ecology guidance WQ-R-95-56, "Vehicle and Equipment Washwater Discharges,"June 1995 (Revised 9/2007). The quality of any discharge to the ground after proper treatment must comply with Ecology's Ground Water Quality Standards,Chapter 173-200 WAC. Contact the Ecology Northwest Regional Office for an NPDES permit application for discharge of washwater to surface water or to a storm drain after onsite treatment. Wash water from residential applications which meet the Ecology guidance for small dischargers may discharge to a landscaped or grassy area where the washwater will soak into the ground and/or evaporate. Required BMPs Vehicle/equipment washing should be performed in one of the following locations: 1. At a commercial washing facility in which the washing occurs in an enclosure and drains to the sanitary sewer,or 2. In a building constructed specifically for washing of vehicles and equipment,which drains to a sanitary sewer. If vehicle/equipment washing must be conducted outdoors,it shall occur in a designated wash area with the following features: 1. The area shall be paved,preferably with Portland cement,and shall be constructed as a spill containment pad to prevent the run-on of stormwater from adjacent areas. The spill containment area shall be sloped so that washwater is collected in a containment pad drain system with perimeter drains,trench drains,or catchment drains. The containment pad shall be sized to extend out a minimum of four feet on all sides of the vehicles and/or equipment being washed. 2. A Portland cement spill containment pad is required for steam cleaning activities. 3. The washwater shall be conveyed to a sump(like a grit separator)and then to the sanitary sewer, or other appropriate wastewater treatment or recycle system.An NPDES permit may be required for any washwater discharge to a storm drain or receiving water after treatment. Contact the Ecology Northwest Regional Office for NPDES permit requirements. Volume IV—Source Control 3-6