Michael Murray, Ph.D. National Wildlife Federation and 12 co-authors

1. Michael Murray, Ph.D. National Wildlife Federationand 12 co-authors A Framework for Monitoring the Response to Changing Mercury Releases National Water Quality Monitoring Conference San Jose, CA May 10, 2006 Developed through workshop organized by Society of Environmental Toxicology and Chemistry, September 2003

2. Fish Consumption Advisories for Mercury NOTE: This map depicts the presence and type of fish advisories issued by the states for mercury as of December 2004. Because only selected waterbodies are monitored, this map does not reflect the full extent of chemical contamination of fish tissues in each state or province. Source: U.S. EPA, National Listing of Fish Advisories

3. Source: EPA, Controlling Power Plant Emissions: Emissions Progress (EPA Web site)

4. September 2003 Workshop • Organized by Society of Environmental Toxicology and Chemistry, involving 33 mercury researchers, and funded by U.S. Environmental Protection Agency, Electric Power Research Institute and others • Rationale: • Voluntary and regulatory Hg programs continue to be implemented • No systematic, integrated national monitoring done to assess trends in Hg in various environmental compartments • Need for more information on environmental impact of specific programs (e.g. rule affecting U.S. coal-fired power plants)

5. Workshop Participants Academia • Robert P. Mason, UMCES, CBL • Michael Newman, VIMS • William W. Bowerman, Clemson University • Joanna Burger, Rutgers University • Charles Driscoll, Syracuse University • Cynthia C. Gilmour, Smithsonian Environmental Research Center • James P. Hurley, University of Wisconsin • Marc Lucotte, Univ. Quebec, Montreal • Nicola Pirrone, CNR-Institute for Atmospheric Pollution, Italy • James G. Wiener, University of Wisconsin-La Crosse • Marti F. Wolfe, California State University-Chico Industry/NGO/Other • Reed C. Harris, Tetra Tech, Inc. • Michael Murray, National Wildlife Federation • Robin J. Reash, American Electric Power • Steven S. Brown, Rohm & Haas Company • David C. Evers, BioDiversity Research Inst. • John J. Jansen, Southern Company Services, Inc. • Dennis Leonard, Detroit Edison • Leonard Levin, Electric Power Research Institute • Donald B. Porcella, Environ. Science and Management • Edward J. Zillioux, Florida Power and Light Company  Government • David P. Krabbenhoft, USGS/WRD • Tamara Saltman, EPA Clean Air Markets Div. • Michael L. Abbott, Idaho National Engineering and Env. Laboratory • Robert B. Ambrose, US EPA/ORD • Thomas D. Atkeson, FL Dept. Environ. Protection • Drew Bodaly, Freshwater Institute, Canada • O. Russell Bullock, Jr., US EPA/ORD • Dan R. Engstrom, St. Croix Watershed Res. Station • Richard A. Haeuber, US EPA Headquarters • Steven E. Lindberg, Oak Ridge National Laboratory (ret.) • John Munthe, Swedish Environ. Res. Institute • Mark Nilles, USGS • Edward Swain, Minnesota Pollution Control Agency (Bold indicates co-authors on presentation)

6. September 2003 Workshop – Approach • Format: plenary discussions and deliberation/drafting within four work groups (airsheds and watersheds, sediments/water, aquatic biota, wildlife) • General approach: • Establish criteria for Hg indicators • Use criteria to identify indicators of Hg contamination in various environmental matrices • Using indicators, develop framework that can form basis of national/continental monitoring network to assess responses to changes in Hg releases

7. Products • Overview paper in Environmental Science and Technology (Mason et al., 2005, 39(1):14A-22A) • Presentations (ICMGP, 2004; EUEC, 2005, EPA/USGS Hg Roundtable, 2005) and Congressional briefings • Book to be published by SETAC/Taylor & Francis (2006)

8. Mercury Cycling is Complex Source: Harris et al. 2006

9. Factors to Consider in Developing Hg Monitoring Network • Magnitude (or potential) of changes in Hg releases and deposition • Larger-scale spatial variability (e.g. local vs. regional vs. global sources) • Temporal variability • Source strength and its changes (e.g., different magnitude of changes in regional sources vs. global) • Differences in response time of systems (e.g., watershed soil vs. water column vs. phytoplankton vs. forage fish tissue Hg) • Factors affecting formation of methylmercury (e.g., organic carbon, redox potential, sulfate, bacterial populations), and additional factors that can alter bioaccumulation and biomagnification in aquatic food webs and exposure in wildlife

10. Criteria Used in Developing Hg Indicators • Ideal indicator characteristics: • Relevant to human health endpoints • Responsive to changes in Hg loadings • Quality historical data available • Adequate data collection infrastructure in place • Sampling and analysis is feasible • Able to adjust for confounding factors • Easily related to other components of ecosystem • Widely applicable (have broad geographic distribution) • For fauna: • Involve fauna with well known life history • Able to be measured non-invasively, or otherwise not significantly impact populations

11. Monitoring Network Structure • Envision sampling within each of approx. 10 ecoregions in U.S. (or North America) • Sampling scheme would involve cluster and intensive sites:

12. Source: EPA, Regulatory Impact Analysis for Clean Air Mercury Rule, 2005

13. Types of Hg Indicators – Airsheds, Watersheds, and Characterization in Water and Sediments Sampling frequency would range from quarterly (e.g., sediment sampling at intensive sites) to every 5-10 years (total Hg accumulation in sediments).

14. Types of Hg Indicators – Aquatic Biota and Wildlife *: Could analyze plankton to assist with mechanistic interpretations. **: Sampling tissues – generally blood, egg, fur or feathers, as appropriate; annual schedule (with sensitivity to seasonal variability).

15. Other Aspects of Monitoring Program • Need to measure relevant ancillary parameters: • Hydrological parameters, watershed characteristics • Water, sediment chemistry • Biota characteristics (e.g. age, length/weight, sex, condition) • Should take advantage of existing programs, databases to extent practical (e.g., NADP/MDN network, LTER sites, fish tissue monitoring programs) • Coupling measured data with modeling will be essential in fully understanding responses, in particular addressing mechanistic questions; also need to consider statistical issues in trend detection

16. Source: NADP/MDN Web site

17. Mercury Cycling in D-MCM Wet and dry Deposition Volatilization Outflow Hg(0) Inflow/Runoff Reduction Photodegradation Oxidation Hg(II) MeHg Settling/Resusp Diffusion Settling/Resusp Diffusion Bioaccumulation Hg(II) MeHg Burial Burial Demethylation Methylation

18. Mercury Concentrations in Florida Everglades Largemouth Bass From: Atkeson et al., 2003, Integrating Atmospheric Mercury Deposition with Aquatic Cycling in South Florida

19. Everglades: Model Projections of Impact of Load Reductions on Fish Mercury Levels From: Atkeson et al., 2003, Integrating Atmospheric Mercury Deposition with Aquatic Cycling in South Florida

20. Summary • Mercury cycling is complex, and a monitoring network must consider the many factors that affect Hg from source to receptor, with indicators chosen appropriately • A network that includes both primary monitoring data (cluster sites) and use of additional indicators (intensive sites) offers best hope of detecting responses and understanding reasons for them • Network should build on existing efforts, be started as soon as practical, and be in place for at least 15-20 years to fully capture environmental response to changes in Hg releases