This industrial facility is responsible for comprehensive waste handling and environmental services. The project site consists of 2.6 acres. For this site, SoundEarth provides stormwater support to effectively manage the requirements outlined in their Ecology issued National Pollution Discharge Elimination System (NPDES) Industrial Stormwater General Permit (ISGP). Services include quarterly sampling, additional sampling, monthly monitoring, semi-monthly monitoring, composing and submitting quarterly reports and annual reports, corrective actions, designing, coordinating and overseeing construction of the advanced treatment system.
This facility has undergone changes since SoundEarth started providing stormwater consultant support to ensure they stay in compliance with their ISGP. Stormwater was routed to the northeastern side of the facility via pumps and conveyance lines, it passed through an oil/water separator that was installed, to Baker Tanks for stormwater settling and detention before either being used for dewatering or discharging offsite from Outfall A. After installation of the Advanced Treatment System (ATS) in 2017, the Baker Tanks were removed and a chitosan-enhanced sand filtration advanced treatment system was installed on the west side of the shop building. Two Baker Tanks, a 3-pod sand filter, and a control unit allows the stormwater to receive adequate treatment before being discharged from Outfall A. As part of the ATS construction, a trench drain was installed just west of the stormwater vault to intercept any process water discharging form the MERF. Process water is conveyed from the trench drain to an oil/water separator and into a manhole that connects into the City of Seattle sewage system.