A property with a septic system housed a dentist office for several years. The septic tank needs to be emptied but mercury has been detected in the tank. The TCLP results are low enough that it's not hazardous waste, but the total mercury levels are high enough that the local sewage treatment plant that usually accepts septic tank sludge doesn't want it. Any ideas for disposal options on this waste?
In the future, this property won't have a dentist office on it. However, other locations in the County may have dentists discharging to septic systems so we may encounter this situation again. Treatment systems to capture mercury are being installed by dentists throughout King County to reduce mercury discharges.
Thanks for any assistance you can offer.
Alice I. Chapman, PE
King County Hazardous Waste
130 Nickerson St, Suite 100
Seattle, WA 98109-1658