1 **Multi-state Mercury Products Campaign**
**Environmental Law and Policy Center * Mercury Polic** **y Project ***

**Natural Resources Defense Council**

**April 1, 2011**
On behalf of the Multi-state Mercury Products Campa ign 1 , the Environmental Law and Policy Center, the Mercury Policy Project, and the Natural Resources Defense Council, we respectfully submit the following comments on important elements that should be included in the U.S. Environmental Protection Agency’s (EPA’s) proposed dental facility effluent guidelines.
Unlike most pretreatment standards which specify a concentration-based limit, we anticipate a proposal requiring the use of certain equipment suc h as amalgam separators. Under these circumstances, it is vital that the proposal also i nclude a comprehensive set of best practices and operational requirements which ensure the equip ment is functioning and mercury discharges to POTWs are otherwise minimized. Towar d this end, these comments focus on the best practices and operational requirements necessa ry for an effective rule.

**Standard**
The dental facility effluent guideline should requi re an amalgam separator or equivalent technology which includes each of the following cha racteristics:

1. Certified compliant to achieve solids removal effic iency of 99% or greater for separators installed on or after the effective date of the rul e, 2. Receives all dental facility waters likely to come into contact with dental amalgam waste prior to discharge, including wastewater from chair -side water collection units, sinks, traps and drains, and
3. Sized appropriately for the dental office based on anticipated wastewater flow rate (number of chairs served, etc.).

**Required Separator Operation and Maintenance**
The following requirements should be included in th e guideline to ensure that the amalgam separator is properly operated and maintained:

1. Notification requirements. Dental facilities should be required to provide notice to the control authority that includes a certification of separator installation per manufacturer specifications and compliance with Best Management Practices (BMPs).
2. Maintenance and corrective action. The dental facil ity must:

1 The Multi-State Mercury Products Campaign works to advance policies to reduce and eliminate mercury r eleases to the environment from products. The campaign incl udes over twenty state and national environmental a nd public health advocacy groups working together to r educe and eliminate several of the largest product uses of mercury and to reduce mercury releases to the envir onment.2 a. Inspect the separator at least weekly to ensure pro per operation.
b. Maintain the separator in accordance with manufactu rer specifications. This maintenance includes changing the collection boxes or cartridges in accordance with manufacturer specifications and recycling or m anaging the spent amalgam collection boxes or cartridges in accordance with s tate or local law.

c. Periodically certify compliance with separator merc ury removal efficiency standards and maintenance requirements, and BMPs.
d. Notify the control authority within 24 hours after an alarm is triggered or there is some other indication of separator malfunction. Th e facility must undertake corrective action within 24 hours and must submit a report to the control authority that corrective action has been completed within 72 hours.

e. Disinfect separators on a regular basis as recommen ded by the vendor, using non-corrosive, non-oxidizing bio-degradable product s which will not dissolve mercury (no bleach).
3. Record-keeping requirements. The dental facility m ust maintain on its premises the following records for 5 years from the date they ar e created:

a. The manufacturer, model number, serial number, date of installation and number of chairs serviced by the amalgam separator.

b. Written or computerized logs of amalgam waste gener ated and removed from the vacuum system or plumbing.

c. Receipts, manifests, bill of lading and/or tracking number or other certified documentation from the recycler or shipping company , and receiving facility for all amalgam waste shipments.
d. Amalgam separator and chair-side trap installation, inspection and maintenance, and servicing records, including date of installati on, date of each inspection (including dates when separator alarm is triggered) , date of service of each separator or trap, date of description of routine a nd non-routine maintenance activities conducted, and corrective actions, inclu ding reason for malfunction/bypass, if found.

**BMPs Specified in Rule**
Strong BMPs are also an important element of an eff ective dental facility effluent guideline to further minimize mercury releases to wastewater tre atment systems. EPA should include, at least, the following BMPs as part of the effluent g uideline.

The dental office must NOT do any of the following:

1. Flush devices containing amalgam or amalgam waste, such as non-contact amalgam or salvaged amalgam restoration pieces, down the drain or toilet.
2. Rinse devices, including reusable traps, containing amalgam over drains or sinks.
3. Decant any radiographic fixer, water, or other liqu id, containing dental amalgam or liquid in which amalgam was stored, down the drain.
4. Rinse vacuum pump filters over drains or sinks.3

5. Use sodium hypochlorite (bleach) or other chlorine containing products or oxidizing agents that would dissolve mercury to clean or flus h vacuum or wastewater lines.
6. Dispose expended capsules down the drain or toilet.

In addition, the dental facility must do the follow ing:

1. Clean screens, traps and filters before cleaning va cuum lines. 2. Use chair-side traps to capture amalgam waste using the finest screen possible. 3. Maintain vacuum pumps, chair-side traps, and other equipment in accordance with manufacturer specifications, and recycle or manage filters and other wastes in accordance with state and local law. 4. Discontinue use of bulk (elemental) mercury and use only pre-capsulated dental amalgam. Locate any bulk or elemental mercury onsi te and recycle or manage in accordance with state and local law. 5. Establish a training program covering the requireme nts of this rule and applicable state law; the operation and maintenance of discharge con trol equipment; and proper handling, management and disposal of mercury-contai ning material and fixer-solutions. 6. Make information accessible to patients regarding t he health and environmental risks posed by mercury and the availability of non-mercur y alternatives for dental restorations. 7. When plumbing parts are removed or cleaned in the o ffice, the sludge inside the piping should be inspected for the presence of mercury ama lgam. If amalgam is present, it should be removed and managed along with other cont act amalgam waste.

Thank you for your consideration. Please feel free to contact me if you have any questions or need further information.

Sincerely,

Mae Wu Natural Resources Defense Council 1200 New York Ave., NW Washington DC 20005