220 OLYMPIC BLVD VA OUTPATIENT CLINIC 2023-02-09

I the rubble.The loose debris may contaminate stormwater. I Pollutants of concern include toxic organic compounds, hazardous wastes, high pH, heavy metals, and suspended solids. Pollutant Control Approach: Do not expose hazardous materials to stormwater. Regularly clean la II up debris that can contaminate stormwater. Protect the drainage system from dirty runoff and loose partides. Sweep paved surfaces daily. Educate employees about the need to control site activities. I Applicable Operational BMPs: . Identify, remove,and properly dispose of hazardous substances from the building before I beginning construction demolition activities that could expose them to stormwater.Such sub- stances could indude PCBs,asbestos, lead paint, mercury switches, and electronic waste. . Educate employees about the need to control site activities to prevent stormwater pollution, and also train them in spill cleanup procedures. . Keep debris containers,dumpsters, and debris piles covered. I . Place storm drain covers, or a similarly effective containment device,on all nearby drains to prevent dirty runoff and loose particles from entering the drainage system. Place the covers(or devices)at the beginning of the workday. Collect and properly dispose of the accumulated materials before removing the covers I (or devices)at the end of the workday. Use dikes, berms, or other methods to protect overland discharge paths from runoff if Istormwater drains are not present. • Sweep street gutters,sidewalks,driveways, and other paved surfaces in the immediate area of the demolition at the end of each workday. Collect and properly dispose of loose debris and Igarbage. . Lightly spray water(such as from a hydrant or water truck)throughout the site to help control I windblown fine materials such as soil,concrete dust,and paint chips. Control the amount of dust control water so that runoff from the site does not occur,yet dust control is achieved. Do not use oils for dust control. I Suggested Operational BMPs: . Construct a screen to prevent stray building materials and dust from escaping the area during demolition. Size and orient the screen to capture wind-blown materials and contain them onsite. I . Schedule demolition to take place at a dry time of the year to prevent stormwater runoff from the demolition site. I I 2019 Soormwater Management Manual for Western Washington Volume IV-Chapter 7-Page 600