Heavy metals and cyanide
King County local limits are set for heavy metals and cyanide, listed below. The metal limits are for total metals, not dissolved metals. If a company discharges less than 5,000 gallons of wastewater per day, the company must comply only with the instantaneous limits.
Daily Average Maximum
|*Cyanide amenable to chlorination, not total cyanide|
About heavy metals
Heavy metals pass through the sewage treatment plant into the treated effluent released to Puget Sound or through the biosolids used to improve soils. These limits are established to protect these resources.