"Lamperti, Larry" 

<Larry.Lamperti@ci.cor

vallis.or.us> 

12/21/2007 11:25 AM 

To Group Ow-Docket@EPA 

cc

"Hanthorn, Dan" <Dan.Hanthorn@ci.corvallis.or.us>, 

"Penpraze, Tom" 

<Tom.Penpraze@ci.corvallis.or.us>, "Sinclair, 

Shane" <Shane.Sinclair@ci.corvallis.or.us>, 

<gillaspie@oracwa.org>, 

<bfletcher@oregondental.org> 

bcc

Subject Attention Docket ID No. EPA-HQ-OW-2006-0771 

 

 

December 21, 2007 

Water Docket 

Environmental Protection Agency 

Mailcode: 4203M 

1200 Pennsylvania Ave., NW 

Washington, DC 20460 

Attention Docket ID No. EPA-HQ-OW-2006-0771 

The City of Corvallis is a municipality located in the Upper Willamette 

Basin of Oregon and provides wastewater treatment to a population of 

53,165. The City of Corvallis shares EPA's commitment to a clean and 

healthy environment. More specifically, the City believes that the 

discharge of toxic pollutants should be reduced so that water quality is 

not impaired. The City also believes that mercury discharged from 

dental offices is effectively reduced through Best Management Practices 

(BMPs) that are implemented at the local level. 

In keeping with the City's Utility Division motto of "Enhancing 

Community Livability Through Improved Water Quality" the City partnered 

with the Oregon Dental Association (ODA) in 2003 to implement BMPs for 

managing dental waste, including mercury and amalgam. 

In response to EPA's request for comments regarding dental mercury, the 

City of Corvallis offers the following comments: 

1) EPA's current assumption that amalgam collected in chairside traps 

and vacuum pump filters is disposed as solid waste is not accurate. In 

Oregon many jurisdictions with approved industrial pretreatment 

programs, like Corvallis, have implemented the ODA's BMPs for amalgam. 

Compliance with the ODA's BMPs require that the amalgam be either picked 

up by a commercial recycler, or taken or mailed to a commercial 

recycler. Landfill disposal of amalgam is not acceptable to the City of 

Corvallis and the Oregon Dental Association. 

2) All forty-two (42) dentists practicing in the City of Corvallis have 

implemented the ODA's BMPs for mercury and amalgam (see attached file) 

instead of the ADA's BMPs. The cost for a dentist to recycle the 

amalgam can range from $450 - $950 per year, depending on the recycling 

service used. This cost is based on a dentist who places 50 amalgam 

fillings per month and removes 25 amalgam fillings per month. 

 <<BMP document Revised October 2007.doc>> 
3) The City believes that the implementation of BMPs is highly effective 

in reducing the daily mass load of mercury in the influent to the 

Corvallis Wastewater Reclamation Plant. By the end of 2004, 100% of 

Corvallis dentists had implemented the BMPs. The data below shows that 

the daily influent mass load has been reduced 79%. 

 Before BMPs Implemented: 

After BMPs Implemented: 

 Date Influent (lbs/Day) 

Date Influent (lbs/Day) 

 03/05/01 0.05 

03/09/04 0.02 

 03/06/01 0.08 

03/10/04 0.01 

 03/07/01 0.06 

03/11/04 0.02 

 07/16/01 0.09 

07/20/04 0.01 

 07/17/01 0.09 

07/21/04 0.02 

 07/18/01 0.09 

07/22/04 0.02 

 03/18/02 0.09 

02/23/05 0.02 

 03/19/02 0.08 

02/24/05 0.01 

 03/20/02 0.03 

02/25/05 0.01 

 07/29/02 0.18 

08/15/05 0.01 

 07/30/02 0.13 

08/16/05 0.02 

 07/31/02 0.09 

08/17/05 0.02 

 02/10/03 0.02 

03/06/06 0.01 

 02/11/03 0.01 

03/07/06 0.01 

 02/12/03 0.01 

03/08/06 0.01 

 07/28/03 0.10 

07/17/06 0.01 

 07/29/03 0.01 

07/18/06 0.02 

 07/30/03 0.02 

07/19/06 0.02 

 

02/12/07 0.01 

02/13/07 0.01 

02/14/07 0.01 

08/27/07 0.02 

08/28/07 0.01 

08/29/07 0.01 

 Average: 0.0683 lbs/Day 

Average: 0.0142 lbs/Day 
 

Percent Reduction: 79% 

4) Cost and burden to POTW: Implementing voluntary BMPs in the City of 

Corvallis involved approximately 185 hours of staff time and a total 

cost of $5000 (includes time and materials). 

5) The Corvallis Wastewater Reclamation Plant has not experienced any 

known interference or pass through problems associated with dental 

mercury discharges. 

6) The City of Corvallis has forty-two (42) dentists practicing within 

the City's jurisdiction. By the end of 2004, all forty-two dentists 

voluntarily implemented the BMPs. The City of Corvallis believes that a 

voluntary program can be very effective in reducing dental mercury 

discharges. Additionally, the 2007 Oregon Legislature passed Senate 

Bill 704 that now requires all dentists practicing in Oregon to 

implement the ODA's BMPs. Whether voluntary or not, dental BMPs are 

highly effective in reducing mercury discharges from dental offices when 

implemented at the State or local level. 

In conclusion, the City of Corvallis is the recipient of EPA's 2006 

National First Place Cleanwater Act Recognition Award for Pretreatment 

Program Excellence. Obviously, the City takes its pretreatment 

responsibilities seriously. Although not nationally recognized, many 

other Oregon pretreatment programs also share the same commitment to 

pretreatment excellence. This commitment to pretreatment excellence is 

accomplished through limited budgets. For example, the forty-two 

dentists located in Corvallis are practicing in thirty-one (31) dental 

offices. If EPA were to establish national categorical pretreatment 

standards for dental mercury discharges, the number of Significant 

Industrial Users in Corvallis would increase from 3 to 34. As a result, 

pretreatment oversight for the dental sector would significantly 

increase due to the time involved in issuing permits, and conducting 

required annual inspections and monitoring. With a pretreatment staff 

of one person and a limited budget, the City's resources would be 

unnecessarily diverted to a sector that can easily and effectively be 

regulated using BMPs implemented at the local or State level. Based on 

the evidence presented in this testimony, dental mercury discharges can 

be reduced without federal regulation. 

This concludes the City of Corvallis comments regarding EPA's request 

for comments regarding the use of BMPs for reducing dental mercury 

discharges. The City appreciates the opportunity to submit comments on 

this topic. If you have any questions or would like to discuss these 

comments, please contact me. 

Larry Lamperti 

Environmental Analyst 

City of Corvallis 

Public Works 

PO Box 1083 

Corvallis, OR 97339-1083 

Phone: 541-766-6729 x5282 

FAX: 541-766-6753 

e-mail: larry.lamperti@ci.corvallis.or.us