Amalgam Separator Rule

EPA Dental Amalgam Rule: 
Missouri DNR Implementation


In June 14, 2017, U.S. Environmental Protection Agency (EPA) finalized technology-based pretreatment standards under the Clean Water Act to reduce discharges of mercury and other metals from dental offices into municipal sewage treatment plants known as publicly owned treatment works (POTWs).

The rule became effective July 14, 2017 and compliance with the standards for most dentists is July 14, 2020. A one-time compliance report for most dentists is due October 12, 2020. Read the Dental Amalgam Rule Facts following for more complete information. 

Dental offices, which discharge mercury and other metals present in amalgam used for fillings, are a significant source of mercury discharges to POTWs; these metals are subsequently released to the environment.

The federal rule requires dental offices to comply with requirements based on the ADA recommended practices, including the use of amalgam separators. Removing mercury when it is concentrated and easy to manage, such as through low-cost amalgam separators at dental offices, is a common-sense solution to managing mercury that would otherwise be released to air, land and water. The EPA Dental Amalgam Rule website has a Frequently Asked Questions document for the Dental Office Category Rule that may be helpful.

Compliance with the federal rule will be sought by the POTW with the state-approved industrial pretreatment programs or by the Missouri Department of Natural Resources (DNR).

The following Dental Amalgam Rule Facts are provided by DNR to assist dentists to come into compliance with the Federal Dental Amalgam Rule. 


For answers to questions, contact:
Missouri Department of Natural Resources
Water Protection Program
Compliance and Enforcement Section
Phone: 800-361-4827 or 573-751-1300

D​ental Amalgam Rule Facts

  • To whom is the Dental Amalgam rule applicable?
  • What are the basic requirements of the rule?
  • Who must submit a one-time compliance report?
  • Where do I get a one-time compliance report?
  • Who is the control authority?
  • What does this rule require of POTWs?