Dental Facilities

The Environmental Protection Agency (EPA) is promulgating technology-based pretreatment standards under the Clean Water Act to reduce discharges of mercury from dental offices into publicly owned treatment works (POTW).  The Dental Office Category regulation is codified under 40 CFR Part 441 which was effective on July 14, 2017

Dental facilities that discharge wastewater into a POTW are subject to this rule.  However, there are some exceptions.  Dental dischargers that do not place dental amalgam, and do not remove dental amalgam except in limited emergency or unplanned, unanticipated circumstances are exempt from any further requirements as long as they certify as such in a one-time compliance report to the District.

Dental dischargers that exclusively practice one or more of the following specialties are not subject to any of the rule’s requirements, including submission of a one-time compliance report to the District:

  • Oral pathology
  • Oral and maxillofacial radiology
  • Oral and maxillofacial surgery
  • Orthodontics
  • Periodontics
  • Prosthodontics

Additionally, mobile units are not subject to any of the rule’s requirements, including submission of a one-time compliance report to the District. A mobile unit is a specialized mobile self-contained van, trailer, or equipment used in providing dentistry services at multiple locations.

Dental facilities that do not discharge their amalgam process wastewater into a POTW are also not subject to any of the rule’s requirements, including submission of a one-time compliance report to the District. For example, dental facilities that discharge amalgam process wastewater into a septic system are not subject to this rule

The requirements for dental dischargers subject to the rule are detailed in the rule.  Here, they are summarized as follows:

  • Ensure the removal of dental amalgam solids from all amalgam process wastewater via amalgam separator(s) or equivalent device(s) that meet the standard of the final rule. See § 441.30(a) (1-2) for an existing source and § 441.40 for a new source.
  • Implementation of two best management practices. See § 441.30(b) for an existing source and § 441.40 for a new source.
  • Comply with reporting requirements. See § 441.50(a).
  • Maintain and make available for inspection certain records documenting compliance. See § 441.50(b).

For additional information please visit:

https://www.epa.gov/eg/dental-effluent-guidelines

https://www.epa.gov/sites/production/files/2017-12/documents/dental-office-category_frequent-questions_nov-2017.pdf