Overview For MDC Acceptance of Wastewater From Dental Practices

Dental practices that discharge wastewater to the MDC sewer system must be in compliance with the requirements of Sections 22a-616(d) and 22a-622 of the Connecticut General Statutes (CGS) concerning the management of mercury amalgam. Dental offices are the single largest source of mercury at sewage treatment plants. The installation of amalgam separators, which catch and hold the excess amalgam waste coming from office spittoons, can further reduce discharges of mercury to wastewater. Without these separators, the excess amalgam waste will be released to the sanitary sewer system and eventually the mercury will be discharged to the environment.

The Connecticut Department of Energy and Environmental Protection (DEEP) has developed Best Management practices (BMPs) for dental practices. All dental practitioners, who store, use, or otherwise handle mercury amalgam, must comply with the state BMPs.

The BMPs require that:

  • an amalgam separator (meeting certain requirements) must be installed,
  • inspections must be performed and documented,
  • all dentists and hygienists must be properly trained to follow the BMPs, and,
  • each dental office must have information about mercury amalgam fillings and possible alternatives available to patients.

A Certification Form on which dental practitioners certify that their practice(s) or clinic(s) is in compliance with the state adopted BMPs must be submitted to DEEP.

More information on Dental BMPs can be found at: