EPA amalgam separator rule: what every office that touches amalgam has to have, keep and file

What it says#

In June 2017 the EPA added dental offices to its effluent guidelines as their own category, 40 CFR Part 441. The point is mercury: amalgam scrap that goes down a chairside drain ends up at the municipal treatment plant, and the rule keeps it out of the sewer at the office.

Three things are required of an office the rule covers.

First, an amalgam separator on every line that carries amalgam process wastewater, certified to either ANSI/ADA Specification 108 (2009, with the 2011 addendum) or ISO 11143 (2008), with at least 95 percent removal efficiency, sized for the office's maximum discharge rate. It has to be inspected the way the manufacturer's manual says, the retaining unit replaced on the manufacturer's schedule or when it reaches the fill level the manual specifies, whichever comes first, and a separator that stops working has to be repaired or replaced as soon as possible and no later than 10 business days after the problem is discovered. A separator installed before June 14, 2017 counts until it is replaced or until June 14, 2027, whichever comes first.

Second, two best management practices. Waste amalgam from traps, screens, vacuum filters, instruments, cuspidors or collection devices must not be discharged to the sewer. And dental unit water lines, chairside traps and vacuum lines that carry amalgam wastewater must not be cleaned with oxidizing or acidic cleaners that have a pH lower than 6 or greater than 8; the rule names bleach, chlorine, iodine and peroxide.

Third, paperwork. A One-Time Compliance Report goes to the Control Authority, which is the local sewer utility in most of the country and the state agency in a few states. Existing offices had to file it by October 12, 2020. A new office files within 90 days of first discharging wastewater. A new owner files a fresh one within 90 days of the transfer. The report names the facility, its owners and operators, the number of chairs and how many can have amalgam present, the separator's make, model and installation year, and certifies that the equipment meets the standard and the two practices are in place.

Who it applies to#

Any dental discharger that sends amalgam process wastewater to a publicly owned treatment works. The rule does not apply to offices that exclusively practice oral pathology, oral and maxillofacial radiology, oral and maxillofacial surgery, orthodontics, periodontics or prosthodontics, to mobile units, or to an office that collects all of its amalgam wastewater for hauling to a centralized treatment facility instead of draining it.

An office that does not place amalgam and does not remove it except in limited emergency or unplanned, unanticipated circumstances can certify that to the Control Authority in the One-Time Compliance Report and is then exempt from everything else. Most general practices remove old amalgam routinely, so most general practices are not in that group.

The compliance dates are fixed: existing sources by July 14, 2020, and any new source from July 14, 2017 onward as of its first discharge.

What changed#

Before 2017 there was no federal requirement. About a dozen states and a number of cities had their own separator mandates, and the ADA had best-practice guidance, but an office in most of the country could legally run amalgam scrap into the drain. The federal rule made the separator, the two drain practices and the report universal, and turned the local sewer authority into the inspector.

Where the source is#

The EPA's Dental Effluent Guidelines page is the plain-language home for the rule, its fact sheets and the list of Control Authorities by state. The rule itself is 40 CFR Part 441, published in the Federal Register on June 14, 2017 at 82 FR 27176; the section numbers above (441.10 applicability, 441.30 standards, 441.50 reporting) are where each requirement lives. The link opens the EPA page.