1. Assessment of Trends in Hg- Related Data Sets & Critical Assessment of Cause & Effect for Trends in Hg Concentrations in Florida Biota C.D. Pollman, Tetra Tech D.B. Porcella, Environmental Science & Management R. Husar, Lantern Corporation J. Husar Lantern Corporation R. Roberson, RMB Associates P. Frederick, University of Florida M. Spalding, University of Florida 13 December 2001

2. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE HOW IT ALL STARTED: Biota Trend #1 - Recent Declines in Hg in Largemouth Bass collected from the Florida Everglades. Data from T. Lange (2000).

3. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE HOW IT ALL STARTED: Biota Trend #2 - Concomitant Declines in Hg in Feathers of Everglades Great Egret Nestlings. Data from P. Frederick (2000).

4. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE HOW IT ALL STARTED: Biota Trend #3 - Comparatively Rapid Response By Aquatic Biota in Everglades Predicted to Occur in Response to Reductions in Atmospheric Loading Rates of Hg.

5. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE HOW IT ALL STARTED: Comparision of measured MSW Hg emissions (concentrations) in south Florida with the national inventory on MSW emissions compiled by Franklin and Kearney for USEPA

6. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Primary Objective BASIC PREMISE: If changes in Hg emissions and deposition have occurred, and if this in turn produces a comparatively rapid change in biota, contemporaneous trends in a number of media also should be evident, including:  trends in emissions;  trends in atmospheric chemistry and deposition; and  trends in Hg accumulation rates in recent sediments. OBJJECTIVE: Examine whether the trends in Hg concentrations in south Florida biota are significant, whether the trends (or lack thereof) are consistent with the available data on trends in Hg emissions, atmospheric deposition, and accumulation, and whether other factors need to be invoked to explain the data.

7. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Secondary Objectives Examine data pertaining to long-range transport and deposition of Hg and establish whether there have been changes in the signal to south Florida from these sources. Using E-MCM, verify through model hindcasting whether the trends in largemouth bass are consistent with our understanding of changes in atmospheric loadings of Hg in south Florida. Explore alternative hypotheses using E-MCM: For example, do other perturbations to the Everglades such as hydrologic changes and changes in sulfate loadings offer equally plausible or better explanations of the observed biotic trends.

8. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Overall Approach Test the hypothesis that recent trends in biota Hg concentrations in south Florida are a direct result of emissions reductions in the region as well. CRITICALLY ANALYZE TRENDS IN BIOTA RECONSTRUCT TRENDS IN LOCAL EMISSIONS ESTABLISH LINK BETWEEN THE TIMING AND MAGNITUDE OF EMISSIONS AND THE TIMING AND MAGNITUDE OF BIOTIC RESPONSE.

9. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Material Flows Hg Trend Reconstruction - Update Phase I work supported by FDEP and conducted March – May 2001. Developed trends in Hg emissions drivers for period 1980 – 2000. At May 10 meeting in WPB, scope expanded from analysis of emission drivers to a broader scale Hg budgeting.

10. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Material Flows Hg Trend Reconstruction - Update Independent estimate of atmospheric Hg emissions in S. Florida. Accounting for the total mercury flow in Florida (air, land and water). Re-examining, expanding and updating the national Hg budget with new data.

11. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Approach: Scaling of Development of Hg Budgets National Florida South Florida

12. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE National Hg Trends in Hg Flow Much of analysis derived from Sznopek and Goonan, 2000 which defines recent trend of the national mercury flow, including the primary production, consumption, recycling as well as mercury flow from stocks.

13. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Production – Consumption Cycle Showing Secondary Consumption

14. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE National Hg Flow Trends Apparent Hg supply includes 1  and 2  production, net imports, and government stockpile releases. 1970 – 1986: Main contributors to Hg flow were 1  mine production and imports. 1986 – 1992: Rapid decrease of apparent Hg demand caused by reductions in mercury demand for batteries, paint and fungicide industries. 1993 to present: 1  mine production negligible; 2  production (recycling) increased and stock releases were terminated.

15. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE National Hg Flow Trends

16. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE National Hg Releases to Atmosphere, 1996 From Sznopek and Goonan, 2000; USEPA, 1997.

17. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE National Hg Releases to Atmosphere, 1996 Materials flow schematics for 1996. Blue lines are atmospheric emissions from the EPA (1997) report, adding to 144 Mg/yr atmospheric emissions. The right hand portion of the schematics depicts mercury flow in goods, From Sznopek and Goonan, 2000.

18. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Hg in US Goods and Fuel, 1940 – 1995.

19. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Hg in US Goods and Fuel, 1940 – 1995. 1940-1970, consumption of Hg in consumer goods was not well characterized. In 1940 74% of Hg consumption was categorized as "Other". 1970-1990, electrical and electronic instruments category (including batteries) dominant Hg industrial use. Hg demand for consumer goods drastically reduced beginning ca. 1989. Hg consumption in consumer and industrial goods declined from  1500 Mg/yr in 1989 to  500 Mg/yr in 1995 (U.S. Bureau of Mines, 1940-1995). Hg mobilization in coal has increased since 1940, from ca. <6% of the total to ca. 20% in 1995. Mercury mobilization by petroleum products (using 5 to 50 ppb Hg concentration for crude oil) increased since 1940. Wilhelm (in press) indicates range is more likely 5 – 15 ppb.

20. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Coal in Florida

21. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Petroleum in Florida

22. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Electrical Sector On a national scale, electrical uses of Hg increased steadily between 1947 (< 200 Mg/yr and 1986 (1,000 Mg/yr). 1996 use of Hg was 78 Mg Hg use in electrical sector increased from 14% in early 1960’s to its peak in 1985 of 63% of the total United States consumption.

23. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Electrical Sector – Approach (Lighting) < 1978: U.S. Bureau of Mines (BOM) reported a single mercury consumption number for electrical uses. 1978 – Present: BOM gives inside electrical consumption, battery, switches/wiring, and lighting categories with their cumulative value representing the electrical consumption. Reconstruct Hg in lighting using U.S. Bureau of Census fluorescent and HID lamps domestic shipments. Multiply by Hg content of fluorescent lamps (0.75, 0.55, 0.30) for different time periods, and HID mercury content (0.33 and 0.25) (EPA, 1992, Benazon Environmental, 1998).

24. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Electrical Sector – Approach (Batteries) Approach I (Bureau of Mines Hg consumption data) Electrical switches with Hg not manufactured < 1960 (USEPA, 1997) Switching/wiring use > 1960 relatively stable (  100 Mg/yr) Prior to 1978: Calculate Battery Hg use: Hg battery = Hg Total Electrical – Hg switches, lighting Prior to 1960: Hg battery = Hg Total Electrical – Hg lighting

25. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Electrical Sector – Approach (Batteries) Approach II (retail battery sales) Based on work published by USEPA (1992) Use battery retail sales data from National Electrical Manufacturers Association (NEMA) for 1983-1988, and estimates for 1989, and 1992 Based on, trend was established and used to estimate sales 1967-1982 and 1993-2000, respectively. The amount of mercury battery import was assumed at 15 %.

26. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Comparison of Hg Use in Batteries – National Scale BOM data NEMA data Note: BOM data do not reflect the exports and imports of batteries.

27. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Electrical Sector - National

28. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Electrical Sector - Florida Batteries Lighting Switches/Wiring Note: Scaled from National level data by annual population.

29. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Agricultural/Fungicide Use – Approach Hg consumption in agriculture compiled and reported by Jasinski (1994) and Murphy and Aucott (1999) based on BOM Yearbook data. Hg consumption in fungicide compiled by Sharvelle (1961) and Murphy and Aucott (1999). USDA annual Agricultural Statistics provides drivers for small seed (wheat, barley, oats, rye) consumption in USA. Hg use in fungicides applied to golf courses was estimated by number of golf courses in USA (Scharff, 1970, Ross, 1979, NGF web site). Assume 80 acres/golf course treated with 43 g Hg/acre.

30. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Agricultural/Fungicide Use – Approach Golf courses routinely treated with fungicides late 1950s and 1960s. Before late 1950s, literature all suggests only affected areas were treated with much higher concentrations of fungicides. In 1970s mercury fungicides were gradually substituted with non- mercury fungicides. Hg use for foliage treatment started in 1942. Apples and pears were mainly treated with organomercury compounds. Annual acreage of apples was obtained from USDA Agricultural Statistics and 4.5 g/acre (Murphy and Aucott, 1999) was applied since middle 1940s.

31. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Agricultural/Fungicide Use – Approach Hg use for potato and vegetable seeds (tomatoes, watermelon, beets), soil treatment for cabbage and cauliflower, and flower bulbs and corms is not well documented to apportion the mercury use. Therefore, the remaining mercury (after subtracting small grain, apple, and turf use) in the 1950 and 1960 was apportioned to vegetables and others. Production of wheat, barley, oats, rye and apples is not significant in Florida. Thus, only the Vegetable and Other portion of USA Hg consumption was prorated to Florida, using vegetable acreage ratio of Florida compared to USA vegetable acreage. The golf course mercury fungicide was estimated using Florida golf course statistics (Bureau of Census, annual 1959-2000).

32. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Agricultural/Fungicide Use – Data Sources SeedHg estimateReference Wheat, barley, oats, rye0.3-0.6 g/bushelSharvelle, 1961 Apples4.5-9 g/acreMurphy and Aucott, 1999 Turf43 gr/acreSharvelle, 1961 PotatoesSeed soakingSharvelle, 1961 CabbageSoil treatmentSharvelle, 1961 Vegetables and FruitsSeed soaking, foilage treatment Sharvelle, 1961 Bulbs and cormsBulbs and corms soaking Sharvelle, 1961

33. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Agricultural/Fungicide Use - National

34. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Agricultural/Fungicide Use - Florida

35. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Paints – Approach Late 1950s organomercury compounds (principally phenylmercuric acetate) were added to the water type paints to prolong the paint's shelf life. Use the paint shipment driver and apply the estimated Hg concentration factor to paints. Information on US paint shipments obtained from U.S. Bureau of Census annual Current Industrial Reports. The historical total paint shipments were obtained from U.S. Bureau of Census, 1975.

36. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Paints – National Trend in Driver

37. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Paints – National

38. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Paints – Florida Note: Paint Hg estimate for Florida based on U.S. BOM Hg use and Florida population data. Data are subject to change as better information is obtained.

39. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Synthesis of Florida Trend in Hg Use Use US data and apportion Hg consumption to Florida. Cl 2 and caustic soda manufacturing use of Hg omitted from Florida trends, since manufacturing is external to Florida and the products do not contain Hg. “Other” category also omitted in Florida trend reconstruction. Category described in 1960 Bureau of Mines Yearbook as containing “the quantity of Hg to initiate new capacity of chlorine-caustic soda plants”. Hg in coal for Florida included upper and lower estimates. Used average of the two estimates for trend reconstruction.

40. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Synthesis of Florida Trend in Hg Use Hg in petroleum for Florida was reconstructed using Florida consumption data for petroleum products and mercury content of the particular product (Wilhelm, 2001). The mercury in paints, pharmaceutical, electrical, control, and dental uses were prorated to Florida population. The agricultural mercury was deconstructed, and only Florida specific uses were estimated.

41. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend of Hg Consumption in Florida

42. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Synthesis of Florida Trend in Hg Emissions Use coal and petroleum consumption as described previously Paint: Assume 75% is emitted to the atmosphere (Benazon Environmental, 1998). Laboratory, Electrical, Dental, and Control products: Assume disposal as municipal solid waste. In 1980 there were 500 open dumps in Florida. Open burning of waste was a common method to save landfill space (Solid Waste Management in Florida, FL DEP, 1996 p63). In 1982 one WTE was operating in Florida. In 1995 there were 13 WTE. For 1990-1998 percentage of municipal waste burned in WTE is available (Solid Waste Management in Florida, FL DEP). However, prior to 1980 percentage of municipal solid waste burned is not available. A 16% burning rate was assumed.

43. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend in Hg Emissions in Florida 1930 – 1999

44. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend in Hg Emissions in Florida 1990 – 1999

45. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Comparison of material flow-based estimates of Hg emissions with FDEP direct emissions estimates Note: FL DEP estimates of Hg emissions from municipal waste combustion facilities courtesy of Yi Zhu, FDEP.

46. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Major Florida Hg in Biota Data Sets Lange et al. (FGFWFC) largemouth bass data (n sites = 12, total n = 2001) Frederick et al. Great Egret nestling feather data (n sites = 7 sites; total n = 558; period 1994 - 2001) Zillioux et al. raccoon data

47. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Summary of Fish Data Used in Trend Analysis Data File: Task Through 2000.xls (Lange June 2001 Subsetted.xls) Data Locations: Big Lostmans Creek, East Lake Tohopekaliga, Fowlers Bluff, Indian Camp Creek-Rogers, L-35B Canal, Lake Tohopekaliga, Marsh-15, Marsh-GH, Marsh-OM, Marsh-U3, Miami Canal and L-67A, North Prong Number of Data Points: 1464 measurements of Hg in Largemouth Bass Number of Age Groups: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Period Of Time: 10/31/1988 – 03/14/2001

48. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Statistical Analysis Methods Simple Linear Regression versus Time Mann-Kendall Slope Test-of-Sign Median Slope (computed Sen Slope estimate)

49. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Mann-Kendall Slope Test-of- Sign For all j and k such that j > k where C j is the mercury concentration at time T j. If a total of n samples are collected over time, then there are n(n-1)/2 slope calculations. Sen’s slope estimator is equal the median slope from that of the n(n-1)/2 slope calculations. Mann-Kendall routine is a non-parametric test for zero slope

50. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Why Use the Mann-Kendall Routine? Standard t-test of simple linear regression is misleading when Seasonal cycles are present Data are not normally distributed Data are serially correlated The above conditions over predict the significance of the slope when the true slope is actually zero

51. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Hg Concentration Data Availability for Largemouth Bass

52. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Trend-Adjusted Results of Mann-Kendall Test-of-Sign

53. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Typical Examples of Sen’s Non-parametric Estimator of Slope (µg Hg/g/yr)

54. East Lake Tohopekaliga Data

55. Marsh-U3 Data

56. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Cocoa Beach Terra Ceia Bay Teneroc Clewiston Orange Lake Lake Griffin Lake Mary Jane Lake Kissimmee Alley North L-67 TTW Hidden St. Martins Seahorse Key JW1 Location of Frederick et al. (2001) Great Egret and White Ibis Sampling Sites  Long-term Great Egret monitoring stations, 1994 - 2000

57. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Hg Concentrations in Great Egret Nestling Feathers. Data courtesy of P Frederick (2001). N sites per year ≤ 7. Relative Hg Concentration 0.0 0.2 0.4 0.6 0.8 1.0 1.2 199219941996199820002002 Average Relative Hg Concentration Year

58. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Zillioux et al. South Florida Raccoon Hair MMHg Study - Hypotheses MMHg levels in raccoon hair have changed between museum and modern collections. Raccoon hair MMHg levels are the same when collected from different sites having the same deposition.

59. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE South Florida Raccoon Hair MMHg

60. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE South Florida Raccoon Hair MMHg Conclusions Cannot conclude that there has been a temporal change in MMHg raccoon hair levels. Strong differences between sites with relatively similar deposition. Location is more important than time: Methylation Feeding behavior Other factors do not seem important: size, life-stage, sex, other elements, analytical artifacts

61. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Study Tentative Conclusions Estimates of statewide emissions of Hg (based on materials flow) indicates a large, rapid decline in Hg releases to atmosphere, driven predominantly by reductions in electrical use and cessation of paint product use. Kendall tau test demonstrates significant declining trends LMB Hg concentrations for a number of sites across the state, but patterns are not ubiquitously observed. Canals appear to be the most consistent showing declining trends, while trends for marsh sites are not uniform. Only one site, U3, in the entire data set shows increasing trends, and only for year classes 0 to 2

62. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Study Tentative Conclusions The widespread distribution of declining trends suggests a regional factor, such as atmospheric deposition, or perhaps long-term climatic variables (e.g., changes in hydrology and concomitant effects on geochemistry. Likewise, the within region variability in trends evidenced both in the LMB and raccoon data indicate local biogeochemistry and hydrology appears to play a strong role, perhaps more than deposition. Declines may have stabilized, and limited data from one bird colony suggests perhaps an “uptick” in the trends.

63. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Project Timeline JulyAugSeptNovOctDecJanFebMarApr Jan 1, 2002 Submit 1 st Draft To FCG Feb 23, 2002 Comments Back From FCG Mar 15, 2002 Submit Final To FCG Aug 1 to Oct 31, 2001. Main Hg emission trend analysis. Submit trends to Tt. Nov 1 to Dec 31, 2001. Refine analysis. Draft Report Jul 1-31, 2001. Preliminary analysis of LMB data Oct 1 to Nov 15, 2001. Seasonal Kendall analysis of fish trends. Analyze bird data. Integrate raccoon results. Dec. 1 to Jan 1, 2002. Integrate biota and emission trend results. Prepare draft white paper

64. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Revised Project Timeline JulyAugSeptNovOctDecJanFebMarApr Materials Flow Analysis of Hg Trends. National and Florida scale Preliminary analysis of LMB data Seasonal Kendall analysis of fish trends. Meet with FDEP and submit data request Work with FDEP to try and expedite data transfer Obtain and analyze raw bird data. Integrate raccoon results. ?? Complete Regional (south Florida) analysis. Update and revise report

65. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE NADP/MDN Site Assessment of Changes in Large-Scale Hg Signal - Phase II Analysis

66. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE MDN Precipitation Depth (mm) 0 20 40 60 80 100 120 140 020406080100120140 Glass and Sorensen Precipitation Depth (mm) Precipitation Depth Comparison of Glass & Sorensen (1999) results for Ely, MN with MDN results from same site. Period of overlap is for 1/16/96 through 10/8/96 (n = 25)

67. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Comparison of Glass & Sorensen (1999) results for Ely, MN with MDN results from same site. Period of overlap is for 1/16/96 through 10/8/96 (n = 25) MDN Hg (ng/L) 0 20 40 60 80 100 120 020406080100120 Glass Hg (ng/L) Hg in Wet Deposition

68. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE 0 2,000 4,000 6,000 8,000 10,000 19901991199219931994199519961997199819992000 Hg Deposition (ng/m2-yr) Year Glass & SorensenMDN Annual Hg Deposition Rates, Ely, MN 1990 - 2000

69. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE

70. Results for ANOVA Model

71. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE Plot of ANOVA Deposition Model Residuals vs. Time for Ely, MN. Data from Glass and Sorensen (1999) and MDN. m = +0.025 p = 0.101 Residual Ln Hg Dep Time

72. DRAFT PRELIMINARY DATA SUBJECT TO CHANGE- DO NOT CITE OR QUOTE -3.00 -2.00 0.00 1.00 2.00 3.00 199019921994199619982000 Residual Ln SO4 Dep Time NADP Trend Analysis - Model Residuals vs. Time m = -0.018 p = 0.065