• U.S. EPA Dental Amalgam Rule

    On July 14, 2017, the U.S. EPA promulgated the Dental Effluent Guidelines to reduce discharges of mercury from dental offices into publicly owned treatment works (POTW) (e.g., public sewer system). The Dental Office Category regulation can be found in 40 CFR Part 441. EPA expects compliance with this final rule will annually reduce the discharge of mercury by 5.1 tons as well as 5.3 tons of other metals found in waste dental amalgam to POTWs. Additional information can be found on the U.S. EPA Website.

    What is a Dental Discharger?

    Dental discharger means a facility where the practice of dentistry is performed, including, but not limited to, institutions, permanent or temporary offices, clinics, home offices, and facilities owned and operated by Federal, state or local governments, that discharges wastewater to a POTW.

    Who is Exempted from this New Rule?

    All dental dischargers, with the exception of the dental specialties listed below, must comply with the rule. This rule does not apply to dental dischargers that exclusively practice one or more of the following dental specialties:

    • Oral pathology
    • Oral and maxillofacial radiology
    • Oral and maxillofacial surgery
    • Orthodontics
    • Periodontics
    • Prosthodontics
    • Existing Dental Offices

    • Dental offices that did not have an amalgam separator installed before July 14, 2017, must have a separator that meets the requirements of the rule in service by July 14, 2020.

    • Existing amalgam separators placed in service before July, 14, 2017 may be operated for their lifetime or ten years, whichever comes first.

    • When a separator needs replacement, or the ten-year period has ended and the separator does not meet the standard of the final rule, a dental office must replace it with one that meets the requirements of the final rule.
    • New Dental Offices

      The compliance date for new dental offices ("new sources") is the effective date of the rule: July 14, 2017.

      Best Management Practices

      Dental dischargers regulated under the Dental Amalgam Rule must implement the following EPA Best Management Practices:

    • Waste amalgam including, but not limited to, dental amalgam from chair-side traps, screens, vacuum pump filters, dental tools, cuspidors, or collection devices, must not be discharged to a POTW (e.g., municipal sewage system).

    • Dental unit water lines, chair-side traps, and vacuum lines that discharge amalgam process wastewater to a publicly owned treatment works (e.g., municipal sewage system) must not be cleaned with oxidizing or acidic cleaners, including but not limited to bleach, chlorine, iodine and peroxide that have a pH lower than 6 or greater than 8 (i.e. cleaners that may increase the dissolution of mercury).
    • Reporting Requirements

      Existing and new sources must submit a One-Time Compliance Report to MSD. New sources must submit the completed One-Time Compliance Report Form within 90 days following the introduction of wastewater to the POTW. For existing sources, the One-Time Compliance Report Form must be submitted to MSD no later than October 12, 2020, or 90 days after a transfer of ownership. Download the report form...

      Emergency Amalgam Placement/Removal Standards

      Dental dischargers that place or remove amalgam in limited emergency or unplanned, unanticipated circumstances are not required to install amalgam separators or follow the EPA Best Management Practices. The completed One-Time Compliance Report Form must be submitted to MSD no later than October 12, 2020, or 90 days after a transfer of ownership. Download the report form...

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