1.  Great Lakes Areas of Concern  U.S. urban areas (pink shading)  Large U.S./Canadian 2005 point sources of mercury Type of Emissions Source coal-fired power plants other fuel combustion waste incineration metallurgical manufacturing & other Emissions of Mercury (kg/yr) 10-50 50-100 100–300 5-10 300–500 500–1000 1000–3500

2. Type of Emissions Source coal-fired power plants other fuel combustion waste incineration metallurgical manufacturing & other 2005 Hg Emissions (kg/yr) 10-50 100–300 50-100 5-10 300–500 500–1000 1000–3000 < 5 St. Louis River and Bay AOC Atmospheric Hg Monitoring Sites

3. Type of Emissions Source coal-fired power plants other fuel combustion waste incineration metallurgical manufacturing & other 2005 Hg Emissions (kg/yr) 10-50 100–300 50-100 5-10 300–500 500–1000 1000–3000 < 5 MN Power Boswell Hibbing Taconite US Steel Keewatin Taconite United Taconite Fairlane Plant MN Power Laskin US Steel Minntac Ispat Inland Steel Mining Minorca MURPHY OIL USA INC. SUPERIOR REFINERY Georgia Pacific

4.  Mercury Emissions, especially local and regional  “current” (2005, 2008, 2011…)  Historical (emissions in the past may have been significantly different, e.g., incinerators?)  This is the primary area that I’d need help… we have to get this right!  “Receptor” details, i.e., what points and/or areas do to have model-estimated deposition?  Watershed(s) and sub-watersheds  Lake surface  River?  Interpretation of results?  Comparison against mercury “inventory” in AOC (i.e., in sediments and soil)?  Comparison against deposition elsewhere?  Time trend of deposition?  Groundtruthing the results  MDN (Hg wet deposition) sites in the region  Ambient Hg air concentration data?  Meteorological modeling data to drive local/regional dispersion simulations  Might have to carry out initial analyses using relatively coarse data  If higher-resolution data are needed, these might have to be generated Some of the issues to think about…

5. Local mercury deposition impacts can be dramatically higher than impacts further away from the source Distance results averaged over all directions: Areas generally downwind of the source will have higher deposition fluxes than the averages shown here. Areas generally upwind will have lower fluxes.