1. Testing for Mercury in Plant Effluent Gary Grey HydroQual, Inc.

2. The Mercury Sampling Debate NJDEPs stated purpose for the effluent sampling requirement: Evaluate the effect of the Dental Amalgam Rule on the release of mercury to the environment. Evaluate the effect of the Dental Amalgam Rule on the release of mercury to the environment. DEPs intent is to look at POTW effluent mercury concentrations before and after dentists comply with the Amalgam Rule. DEPs intent is to look at POTW effluent mercury concentrations before and after dentists comply with the Amalgam Rule. It is not DEPs intent to use this data to establish effluent limits. It is not DEPs intent to use this data to establish effluent limits. AEA position on the effluent sampling requirement: POTWs remove mercury and may mask some of the effectivness of Amalgam Rule compliance. POTWs remove mercury and may mask some of the effectivness of Amalgam Rule compliance. POTW influent sampling would be more appropriate for evaluating the effect of the Rule. POTW influent sampling would be more appropriate for evaluating the effect of the Rule. Low level sampling is sensitive to contamination Low level sampling is sensitive to contamination DEP response: Requirement remains as effluent sampling but DEP will welcome influent sampling as well. Requirement remains as effluent sampling but DEP will welcome influent sampling as well.

3. EPA Method 1631E Sample MDL (ng/L) Clean Blanks 0.05 to 0.2 Effluent 1 to 50 Influent 50 to 500 Current NJ WQ standard = 50 ng/L FW 51 ng/L SE/SC NY DEC WQ standard = 0.26 ng/L or MDL (wildlife based criterion) EPA DW MCL = 2,000 ng/L

4. Many Cautions on Contamination

5. Buried in the Method 1631E Protocol is a Statement that Clean Methods Sampling Is Required NJDEP is requiring grab samples

6. Two person sampling team – Clean Hands and Dirty Hands Two person sampling team – Clean Hands and Dirty Hands Segregates diry operations from clean operations. Segregates diry operations from clean operations. Clean Hands handles the sample bottle, collects the sample and returns the bottle to the inner sample bag. Clean Hands handles the sample bottle, collects the sample and returns the bottle to the inner sample bag. We have seen blank detections of 0.2 to 0.4 ng/L in a clean laboratory setting. We have seen blank detections of 0.2 to 0.4 ng/L in a clean laboratory setting. Wisconsin DNR has helpful information posted on their website: http://www.dnr.state.wi.us/org/water/wm/ww/mercury/mercury.htm Wisconsin DNR has helpful information posted on their website: http://www.dnr.state.wi.us/org/water/wm/ww/mercury/mercury.htm http://www.dnr.state.wi.us/org/water/wm/ww/mercury/mercury.htm NJDEP will be posting mercury sampling Q&A and guidance in their website NJDEP will be posting mercury sampling Q&A and guidance in their website Method 1669 Clean Sampling Method

7. Labs Running Method 1631 E Lab NameLocationPhone # MDL (ng/L)Cost ($) Northern Lake ServiceCrandon, WI(715) 478-27770.1396 North Shore Analytical, Inc.Duluth, MN(218) 729-46580.1105 PACE AnalyticalGreen Bay, WI(920) 469-24360.1680 Columbia Analytical ServicesRochester, NY(585) 288-53800.285 Test AmericaNorth Canton, OH(330) 966-92810.12100 Frontier GeoservicesSeattle, WA(206) 622-69600.2105 Battelle Marine SciencesSequim, WA(360) 681-3650-- Brooks Rand LTDSeattle, WA(206) 632-62060.1575 Lancaster LaboratoriesLancaster, PA(717) 656-23000.2110 S-F AnalyticalMilwaukee, WI(800) 300-6700597

8. Mercury Sources Affecting POTWs Ask Hypo suppliers for metals assay

9. In-plant Sources of Mercury

10. Wisconsin POTW Monitoring Results (used to trigger Mercury Management Plans if > 12 ng/L)

11. NY/NJ Harbor Data

12. Summary Make sure the lab is: Make sure the lab is: Certified for Method 1631E Certified for Method 1631E Can achieve an MDL < 1 ng/L Can achieve an MDL < 1 ng/L Will provide sample bottles and Hg-free blank water Will provide sample bottles and Hg-free blank water Low level mercury sampling MUST be a separate effort to itself and not combined with other sampling efforts. Low level mercury sampling MUST be a separate effort to itself and not combined with other sampling efforts. Use dedicated and clean sampling equipment Use dedicated and clean sampling equipment USE CLEAN METHOD SAMPLING USE CLEAN METHOD SAMPLING Collect grab samples and field blanks Collect grab samples and field blanks Expect plant effluent results at 1 to 50 ng/L. Expect plant effluent results at 1 to 50 ng/L. Influent sampling should be conducted as well. Influent sampling should be conducted as well. NJDEP will be posting Q&A regarding the mercury sampling program as well as some guidance on sampling methods. NJDEP will be posting Q&A regarding the mercury sampling program as well as some guidance on sampling methods.