Dental Offices

Managing waste to prevent mercury pollution

A new federal rule regulating dental amalgam waste became effective July 2017. The new rule is consistent with the state-level Dental Amalgam Rule established by the Washington Department of Ecology with support from the Washington State Dental Association. The rule is designed to prevent mercury, in the form of dental amalgam, from entering wastewater, and ultimately being released into the environment. In the aquatic environment, mercury bioaccumulates in fish and shellfish; mercury is a potent neurotoxin that can cause a wide range of health issues.

This new rule requires dental offices that place or remove mercury amalgam to:

  • Operate and maintain a mercury amalgam separator
  • Document maintenance
  • Submit a one-time Compliance Report to LOTT
  • Follow Best Management Practices

Any dental office that began practice after July 14, 2017, must remove dental amalgam solids from all wastewater by using an approved mercury amalgam separator or equivalent before discharging wastewater to the Lacey, Olympia, or Tumwater sewer system. Existing dental offices must install an approved mercury amalgam separator by July 14, 2020.

Dental Amalgam Waste Guide (PDF)

One-Time Compliance Report Form (PDF)