Technical Documents

Technical Documents

Dental Amalgam Rule (40 CFR Part 441) - Information for POTW’s and Dental Dischargers

EPA promulgated 40 CFR Part 441 Effluent Limitations Guidelines and Standards for the Dental Category, on June 14, 2017 with an effective date of July 14, 2017. The new rule regulates mercury discharged in wastewater from dental facilities to a Publicly Owned Treatment Works (POTW) or municipal wastewater treatment plants (WWTP).

Existing sources are those dental dischargers in operation prior to July 14, 2017 and must submit to the Control Authority a one-time compliance report by October 12, 2020. Any dental practice that begins operation on or after July 14, 2017 is a new source and must comply with the Rule. Please see the Fact Sheet for further detail on requirements for equipment, best management practices and reporting and recording keeping and exemptions to the Rule.

For dental offices in locations with an approved pretreatment program the control authority is the POTW. Check the list of municipal pretreatment contacts in NC to determine if there is an approved pretreatment program in your location. Contact the listed pretreatment coordinator for instructions on how to submit compliance reports. Address, phone numbers and email addresses are provided.

For dental offices in locations without an approved pretreatment program the State is the control authority. Complete the One-Time Compliance Report for Dental Dischargers and submit to the State PERCS Branch.

For POTW’s, a cover letter is available to accompany the fact sheet and One-Time Compliance Report should you want to contact your dental dischargers in a survey effort. The One-Time Compliance Report is available as both a PDF and Word document.

Additional information can be found on the NC DEQ PERCS Branch website at:

Related resources:

Dental Discharge Cover Letter Dental Discharge Cover Letter Dental Certification Sample Form Dental Certification Sample Form Dental Discharge Fact Sheet