Dental dischargers (DD) subject to § Part 441, and who place or remove dental amalgam.

Reporting

Those dental offices that discharge to a POTW, hereafter dental dischargers (DD), to whom the rule is applicable (see below) must submit a one-time compliance report (OTCR). OTCR must be signed and certified by a responsible corporate officer, a general partner or proprietor if the DD is a partnership or sole proprietorship, or a duly authorized representative in accordance with the requirements of 40 CFR § 403.12(l). Additional reporting requirements can be found at § 441.50(a). Compliance dates are as follows:

• DD (under any ownership) defined as “existing source” that is discharging into POTW prior to July 14, 2017, must be in compliance with the standards by July 14, 2020, and submit an OTCR certifying such no later than October 12, 2020, or 90 days after a transfer of ownership.
• DD defined as “new source” whose first discharge to a POTW occurs after July 14, 2017, must be in compliance with the standards immediately and submit an OTCR certifying such within 90 days after first discharge to a POTW.

Installation of Amalgam Separators or Equivalent Device

Dental offices that place and/or remove amalgam are required to install an amalgam separator or an equivalent device. All amalgam separators installed after June 14, 2017, shall be sized to accommodate the maximum discharge rate of amalgam process wastewater and be compliant with 1) the American National Standards Institute (ANSI) American National Standard/American Dental Association (ADA) Specification 108 for Amalgam Separators (2009) with Technical Addendum (2011), 2) or the International Organization for Standardization (ISO) 11143 Standard (2008), or 3) subsequent versions so long as that version requires amalgam separators to achieve at least a 95 percent removal efficiency. Compliance with the 95 percent removal efficiency must be assessed by a laboratory that meets the requirements in § 441.30(a)(1)(i).

To determine whether your amalgam separators is compliant with ISO 11143 ANSI/ADA Standard No. 108, check your model at this website. 

All amalgam separators installed on or prior to July 14, 2017, shall be replaced with an amalgam separator that meets these requirements by July 14, 2027, or when the amalgam separator breaks down, whichever comes first.

Record Keeping

As long as the DD is in operation, or until ownership is transferred, the DD must maintain the OTCR and make it available for inspection in either physical or electronic form. DD or an agent or representative of the DD must document separator maintenance and make available for inspection in either physical or electronic form, for a minimum of three years, the following:

• Documentation of the date, person(s) conducting the inspection, and results of each inspection of the amalgam separator(s) or equivalent device(s), and a summary of follow-up actions, if needed.
• Documentation of amalgam retaining container or equivalent container replacement (including the date, as applicable).
• Documentation of all dates that collected dental amalgam is picked up or shipped for proper disposal in accordance with § 261.5(g)(3), and the name of the permitted or licensed treatment, storage or disposal facility receiving the amalgam retaining containers.
• Documentation of any repair or replacement of an amalgam separator or equivalent device, including the date, person(s) making the repair or replacement, and a description of the repair or replacement (including make and model).
• The manufacturer's operating manual for the current device.

Best Management Practices

DD must comply with two best management practices as specified in § 441.30(b) or § 441.40.

1. Waste amalgam including, but not limited to, dental amalgam from chair-side traps, screens, vacuum pump filters, dental tools, cuspidors and collection devices, must not be discharged to a POTW (for example, municipal sewage system).
2. Dental unit water lines, chair-side traps and vacuum lines that discharge amalgam process wastewater to a POTW 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 (in other words, cleaners that may increase the dissolution of mercury).

Some DDs are not required to submit this report. This rule does not apply to mobile units, offices which do not discharge to a POTW, or offices where the practice of dentistry consists only of the following dental specialties: Oral pathology; oral and maxillofacial radiology; oral and maxillofacial surgery; orthodontics; periodontics; or prosthodontics. A DD subject to § Part 441, but (1) it does not place dental amalgam and (2) it does not remove amalgam, except in limited emergency or unplanned and unanticipated circumstances. (See § Part 441, which defines limited emergency circumstances as occurring from once a quarter to 96 times a year).

No action is required from offices which are exempt from this rule. See the applicability section (§ 441.10) to determine if your facility must submit an OTCR.

Most municipalities that have a state-approved pretreatment program will have their own OTCR form which the DD can fill out and send to the state-approved pretreatment facility. Contact the pretreatment facility to request an OTCR form. The Missouri Department of Natural Resources’ OTCR form is available online.

The Sample One-time Compliance Report that can be modified by POTWs with an approved pretreatment program can be download at EPA website.

The term “control authority” refers to a POTW (defined in § 403.3(q)) with a state-approved pretreatment program. Your control authority may be your wastewater utility if it has a state-approved pretreatment program. The following is the current list of municipalities that have a state-approved pretreatment program. 

State Approved Pretreatment Programs

If your wastewater utility does not have such a program, your control authority may be the Missouri Department of Natural Resources. First, determine the name of the wastewater utility to which your facility discharges wastewater. This may not be the city in which your facility operates. The billing address of the wastewater utility may indicate the wastewater utility to which your facility discharges wastewater. If your billing information does not provide that information, please contact your city’s public works department.

For assistance in determining your control authority, contact the Missouri Department of Natural Resources’ industrial pretreatment coordinator (see contact information at the top of the webpage).​

POTWs with an approved pretreatment program must communicate with regulated facilities, enforce this rule and develop, distribute and collect the OTCR. This rule does not recognize dental dischargers as Significant Industrial Users or Categorical Industrial Users, as defined in § 403; therefore, POTWs are not required to conduct monitoring, issue permits to, or inspect dental offices. However, the rule recognizes the approved pretreatment program’s discretionary authority to enforce more stringent activities than what is required in the rule. A POTW may need to conduct surveillance activities to identify occasional and continuing non-compliance.

POTWs are not required to report on dental users in their pretreatment annual reports, maintain a database, or report to EPA. Electronic tracking of some components of the OTCR reports may be useful regarding transfer of ownership.

For POTWs without an approved pretreatment program, no action is required by this rule.