U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2007–5063 

Prepared in cooperation with the Indiana Department of Environmental Management

Mercury in Precipitation in Indiana, 

January 2001–December 2003 
Cover.

Top: National Oceanic and Atmospheric Administration Photo Library (http://www.photolib.noaa.gov/noaa_products), 

Ligonier, Indiana, October 2000. (Photograph by Sam Lashley, National Weather Service Forecast Office, North Indiana) 

Bottom: National Oceanic and Atmospheric Administration Photo Library (http://www.photolib.noaa.gov/noaa_products), 

Fort Wayne, Indiana, July 1999. (Photograph by Joel Esslinger, weather watcher for National Weather Service Forecast 

Office, North Indiana) 
Mercury in Precipitation in Indiana,

January 2001–December 2003

By Martin R. Risch

Prepared in cooperation with the Indiana Department of Environmental Management

Scientific Investigations Report 2007–5063

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

Mark D. Myers, Director

U.S. Geological Survey, Reston, Virginia: 2007

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Although this report is in the public domain, permission must be secured from the individual copyright owners to 

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Suggested citation:

Risch, Martin R., 2007, Mercury in precipitation in Indiana, January 2001–December 2003: U.S. Geological Survey 

Scientific Investigations Report 2007–5063, 76 p. 
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................2

Purpose and Scope ..............................................................................................................................2

Description of the Study Area ............................................................................................................2

Mercury in the Environment.........................................................................................................................2

Mercury in Fish......................................................................................................................................2

Mercury in the Atmosphere................................................................................................................3

The Mercury Cycle ..............................................................................................................................3

Sources of Mercury .............................................................................................................................4

Mercury Monitoring in Indiana ..........................................................................................................5

Study Methods ...............................................................................................................................................6

Selection of Monitoring Locations.....................................................................................................6

Instrumentation of Monitoring Stations............................................................................................9

Collection and Analysis of Precipitation Samples ..........................................................................9

Quality Assurance...............................................................................................................................15

Data Management and Reporting....................................................................................................16

Mercury in Precipitation in Indiana..........................................................................................................18

Weekly Samples..................................................................................................................................18

Total Mercury ......................................................................................................................................19

Methylmercury....................................................................................................................................21

Geographic and Temporal Variability of Mercury in Precipitation.............................................23

Geographic Variability...............................................................................................................23

Seasonal Patterns ....................................................................................................................29

Episodes of High Mercury Deposition ...................................................................................29

Precipitation Normals ...............................................................................................................32

Summary and Conclusions.........................................................................................................................34

Acknowledgments.......................................................................................................................................34

References Cited..........................................................................................................................................35

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at 

Roush Lake monitoring station near Huntington, Indiana, 

January 2001–December 2003.....................................................................................40

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at 

Clifty Falls monitoring station near Madison, Indiana, 

January 2001–December 2003.....................................................................................49

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at 

Bloomington monitoring station near Bloomington, Indiana, 

January 2001–December 2003.....................................................................................58

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at 

Indiana Dunes monitoring station near Porter, Indiana, 

January 2001–December 2003.....................................................................................67

Appendix 2-1. Summary of laboratory quality assurance January 2001–December 2003...........76
iv

Figures

1. Schematic showing sources of mercury and mercury cycling in aquatic 

ecosystems....................................................................................................................................4

2–7. Maps showing:

2. Locations of National Atmospheric Deposition Program Mercury 

Deposition Network monitoring stations in North America, spring 2003 ...................7

3. Monitoring locations for mercury in precipitation in Indiana, 

2001–2003 ..............................................................................................................................8

4. Roush Lake monitoring station for mercury in precipitation in Indiana, 

with nearby stationary sources of mercury emissions ...............................................10

5. Clifty Falls monitoring station for mercury in precipitation in Indiana, 

with nearby stationary sources of mercury emissions ...............................................11

6. Bloomington monitoring station for mercury in precipitation in Indiana, 

with nearby stationary sources of mercury emissions ...............................................12

7. Indiana Dunes monitoring station for mercury in precipitation in Indiana, 

with nearby stationary sources of mercury emissions ...............................................13

8. Photograph of automated precipitation sampler at monitoring station for 

mercury in precipitation in Indiana..........................................................................................14

9. Diagram of automated precipitation sampler at monitoring station for mercury 

in precipitation in Indiana..........................................................................................................14

10. Photograph of recording rain gage at monitoring station for mercury in 

precipitation in Indiana..............................................................................................................15

11–13. Graphs showing:

11. Distribution of total mercury concentrations in weekly samples at four 

monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003.........................................................................................21

12. Distribution of total mercury deposition in weekly samples at four 

monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003.........................................................................................23

13. Annual total mercury deposition and annual precipitation at four 

monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003.........................................................................................24

14. Map showing National Atmospheric Deposition Program Mercury Deposition 

Network monitoring stations with annual precipitation-weighted total mercury 

concentrations in 2003 and ranges of total mercury concentrations for 

eastern North America ..............................................................................................................27

15. Map showing National Atmospheric Deposition Program Mercury Deposition 

Network monitoring stations with annual total mercury deposition in 2003 

and ranges of total mercury deposition for eastern North America..................................28

16. Graphs showing seasonal total mercury deposition and seasonal precipitation 

at four monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003..................................................................................................30

17. Graphs showing seasonal precipitation at four monitoring stations for 

mercury in precipitation in Indiana, January 2001–December 2003, with 

precipitation normals, 1971–2000.............................................................................................33
Tables

1. Stationary sources and estimated annual mercury emissions to the 

atmosphere in Indiana in 2001....................................................................................................5

2. Characteristics of monitoring stations for mercury in precipitation in Indiana.................6

3. Weekly samples at four monitoring stations for mercury in precipitation in 

Indiana, January 2001–December 2003 ..................................................................................19

4. Total mercury concentrations in weekly samples at four monitoring stations 

for mercury in precipitation in Indiana, January 2001–December 2003............................20

5. Total mercury deposition in weekly samples at four monitoring stations for 

mercury in precipitation in Indiana, January 2001–December 2003..................................22

6. Methylmercury concentrations and methylmercury deposition in weekly 

samples at four monitoring stations in Indiana, January 2001–December 2003..............25

7. Normalized total mercury deposition and volume-weighted total mercury 

concentration at four monitoring stations for mercury in precipitation in 

Indiana, January 2001–December 2003 ..................................................................................26

8. Median total mercury and methylmercury deposition and concentrations, in 

weekly samples grouped by season, at four monitoring stations for mercury 

in precipitation in Indiana, January 2001–December 2003..................................................31

9. Weekly samples with episodes of high mercury deposition at four monitoring 

stations for mercury in precipitation in Indiana, January 2001–December 2003.............31

10. Precipitation normals, 1971–2000, and annual precipitation at four monitoring 

stations for mercury in precipitation in Indiana, January 2001–December 2003.............32
vi

Conversion Factors, Datum, and Abbreviations

Multiply By To obtain

Length

inch (in.) 25.4 millimeter (mm)

millimeter (mm) 0.03937 inch (in.)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Area

acre 4,047 square meter (m2

)

square mile (mi2

) 2.590 square kilometer (km2) 

Volume

milliliter (mL) 0.06102 cubic inch (in3

)

Mass

pound, avoirdupois (lb) 0.4536 kilogram (kg) 

pound per year (lb/yr) 0.4536 kilogram per year (kg/yr)

ton, short (2,000 lb) 0.9072 megagram (Mg) 

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows:

°C = (°F - 32) / 1.8

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).

Concentration of mercury in water is given in nanogram per liter (ng/L).

Solubility of mercury in water is given in gram per liter.

Wet deposition of total mercury and methylmercury is given in nanogram per square meter 

(ng/m2) and in nanogram per square meter per inch of precipitation( ng/m2/in.).

Abbreviations

IDEM Indiana Department of Environmental Management

MDN Mercury Deposition Network

NADP National Atmospheric Deposition Program

NTN National Trends Network

QA Quality Assurance

QC Quality Control

RAPIDS Regional Air Pollutant Inventory Development System 

USGS U.S. Geological Survey
Abstract

Mercury in precipitation was monitored during 2001 

through 2003 at four locations in Indiana as part of the 

National Atmospheric Deposition Program-Mercury Deposition Network (NADP-MDN). Monitoring stations were operated at Roush Lake near Huntington, Clifty Falls State Park 

near Madison, Monroe County Regional Airport near Bloomington, and Indiana Dunes National Lakeshore near Porter. 

At these monitoring stations, precipitation amounts were 

measured and weekly samples were collected for analysis of 

total mercury and methylmercury by low-level methods. Wet 

deposition was computed with the total mercury and methylmercury concentrations and the precipitation amounts. 

In 3 years of weekly samples collected at the four monitoring stations, the volume-weighted total mercury concentration was 11.5 ng/L (nanograms per liter). As a reference for 

comparison, the total mercury concentration in 47 percent 

of the samples analyzed was greater than the Indiana waterquality standard for mercury (12 ng/L, protecting aquatic 

life) and nearly all of the concentrations exceeded the Indiana 

water-quality standards for mercury in the Great Lakes system 

(1.8 ng/L, protecting human health, and 1.3 ng/L, protecting 

wild mammals and birds). The precipitation-weighted concentrations at three of the monitoring stations in Indiana in 2003 

were in the top 40 percent of all monitoring stations in the 

NADP-MDN and the concentration at Indiana Dunes was the 

eighth highest in the NADP-MDN for 2003.

At the four monitoring stations during the study period, 

the mean weekly total mercury deposition was 243 ng/m2 

(nanograms per square meter) and mean annual total mercury 

deposition was 12,623 ng/m2. The annual mercury deposition 

at the four monitoring stations in Indiana in 2003 was in the 

top 40 percent of all monitoring stations in the NADP-MDN 

and the annual mercury deposition at the Clifty Falls station 

was the tenth highest in the NADP-MDN for 2003.

For the 3-year period, the median methylmercury concentration in weekly samples was 0.058 ng/L with a maximum of 

5.77 ng/L. Normalized methylmercury deposition was 

2.09 ng/m2 per inch of precipitation and methylmercury deposition was 0.7 percent of the total mercury deposition. The 

annual and mean weekly methylmercury deposition was highest at the Roush Lake station. Among the monitoring stations 

in the NADP-MDN with methylmercury data, methylmercury 

deposition at the monitoring stations in Indiana appeared to be 

higher than at eight stations in Wisconsin and Minnesota for 

that same time period, although methylmercury concentrations 

in Indiana were similar to or lower than those in Wisconsin 

and Minnesota.

Geographically, the weekly total mercury concentrations 

at Indiana Dunes and Clifty Falls were statistically higher than 

concentrations at Bloomington, although a statistical difference in weekly total mercury deposition was not found among 

the four monitoring stations. Annual mercury emissions from 

sources in the vicinity of Indiana Dunes and Clifty Falls in 

2001 were more than 10 times those at Bloomington, although 

other factors may help explain the differences in total mercury 

concentrations, such as the types of mercury emissions, mercury transport from sources outside Indiana, and meteorological conditions.

Mercury concentrations and deposition varied at the four 

monitoring stations during the 3-year period. Total mercury 

concentrations in weekly samples ranged from 1.54 to 77 ng/L 

and weekly mercury deposition ranged from 0.8 to 

2,456 ng/m2. Data from weekly samples exhibited seasonal 

patterns. Total mercury concentrations and deposition were 

highest in spring and summer and lowest in winter. Methylmercury concentrations were highest in winter and methylmercury deposition was highest in spring. Annual precipitation at 

the four monitoring stations was highest in 2003, exceeding 

the precipitation normals in spring and summer 2003. Annual 

mercury deposition in 2003 at the Roush Lake, Clifty Falls, 

and Indiana Dunes was as much as 41 to 67 percent higher in 

2003 than in 2001 or in 2002 at those stations. 

Total mercury deposition that was more than 10 percent 

of the mean annual deposition (1,262 ng/m2

) was recorded 

in 11 of 551 weekly samples from the study period. These 

samples contained approximately 3 inches or more of rain and 

most were collected in spring and summer 2003. The highest deposition (2,456 ng/m2

 in a sample from Roush Lake) 

was 15.7 percent of the annual deposition at that station and 

approximately 10 times the mean weekly deposition for 

Indiana. High deposition recorded in three weekly samples at 

Clifty Falls contributed 31 percent of the annual deposition at 

that station in 2003. Weekly samples with high mercury deposition may help to explain the differences in annual mercury 

deposition among the four monitoring stations in Indiana.

Mercury in Precipitation in Indiana, 

January 2001–December 2003

By Martin R. Risch
Introduction

A monitoring program for mercury in precipitation was 

operated in Indiana by the U.S. Geological Survey (USGS) in 

cooperation with the Indiana Department of Environmental 

Management (IDEM).

Purpose and Scope

This report presents and interprets mercury data from 

precipitation samples collected concurrently at four monitoring stations in Indiana, January 2001–December 2003. Data 

on total mercury and methylmercury concentrations (mass per 

unit volume of precipitation) are included with the computed 

total mercury and methylmercury wet deposition (mass 

per unit area per unit time). Quality assurance for mercury 

concentrations and precipitation measurement is described. 

Geographic variability and seasonal patterns in mercury concentrations and mercury wet deposition are examined. Annual 

mercury wet deposition is compared with episodes of high 

mercury deposition and precipitation normals.

Description of the Study Area

Indiana is 35,887 mi2 in size, 38th in geographic area in 

the Nation. The State population estimate in 2003 was 

6.2 million, 14th in the Nation; population density was 

172.7 per mi2. Children are one fourth of the total Indiana 

population1 (Indiana Business Research Center, 2004). Indiana 

has 35,673 mi of rivers, 575 publicly owned lakes and reservoirs (106,205 acres), 813,000 acres of wetlands, and 59 mi of 

Lake Michigan shoreline (Indiana Department of Environmental Management, 2004).

The climate of Indiana is continental, influenced mainly 

by eastward-moving cold polar and warm gulf-air masses. 

The low-pressure centers formed by the interaction of these 

air masses are the major sources of precipitation in Indiana. 

Spring and early summer are normally the wettest periods 

of the year, as storm systems tap moisture from the Gulf of 

Mexico and travel across Indiana. Early fall is generally the 

driest period. Seasonal patterns may vary statewide, particularly in the summer when isolated thunderstorms are common 

and during the winter when lake-effect snows fall in northern 

Indiana. Mean annual temperature in Indiana is approximately 

52°F and ranges from 49.6°F in the north to more than 54.8°F 

in the south (Purdue Applied Meteorology Group, 2005).

The statewide mean annual precipitation is 41.5 in. and 

ranges from 37 in. for northern Indiana to nearly 47 in. for 

southern Indiana. Snow fall (as liquid) accounts for 2 to 7 in. 

of the mean annual precipitation, with the greatest amounts of 

1

According to the Indiana Business Research Center (2004), children less 

than 4 years in age (0.43 million) plus children 5 to 17 years in age 

(1.17 million) total 1.6 million of the 6.2 million total Indiana population 

(25.8 percent).

snowfall in northern Indiana (Morlock and others, 2004; Purdue Applied Meteorology Group, 2005). According to Clark 

(1980), of the mean annual precipitation in Indiana, approximately 68 percent returns to the atmosphere through evapotranspiration, 24 percent enters streams and lakes through 

surface runoff, and 8 percent recharges ground water. Generally, runoff is greatest in areas of the state with steep slopes 

and relatively impermeable soils, which are characteristic of 

much of the southern third of Indiana.

Mercury in the Environment

Mercury in aquatic ecosystems is a public-health concern 

and a threat to wildlife because it accumulates and magnifies 

in aquatic food chains, making some fish unsafe to eat. Much 

of the mercury in most aquatic ecosystems comes from atmospheric deposition by precipitation and mercury emissions to 

the atmosphere from human activity have been implicated for 

most of the mercury in fish in the U.S. (U.S. Environmental 

Protection Agency, 1997a).

Mercury in Fish

Mercury—especially in the organic form, methylmercury—can affect the central nervous system of adults and 

children. An important route of exposure to methylmercury 

for some humans is eating fish caught in rivers and lakes. 

Because their nervous systems are still in development, infants 

and young children are predicted to have a greater susceptibility than adults to the detrimental effects of methylmercury 

(National Research Council, 2000). Wildlife also are threatened because mammals and birds can suffer central-nervoussystem damage from mercury in the fish they eat (Krabbenhoft 

and Wiener, 1999).

Methylmercury is produced from inorganic mercury by 

a microbial process that occurs under certain conditions in 

aquatic ecosystems. Fish living in aquatic ecosystems with low 

concentrations of inorganic mercury are known to accumulate methylmercury in their tissue (Krabbenhoft and Rickert, 

1995). Concentrations of methylmercury magnify up the food 

chain so that higher-level organisms tend to accumulate the 

highest levels of methylmercury.

Mercury has been detected in nearly all fish-tissue samples collected in Indiana since 1983 (Stahl, 1997). Concentrations of mercury in some tissue samples from fish caught in 

Indiana waters have prompted State health officials to issue 

advisories that warn about human consumption of these fish 

(Indiana State Department of Health and others, 2001, 2002, 

2003). These advisories apply statewide to certain sizes and 

species of fish and include additional warnings for specific 

streams and lakes. In 2004, mercury advisories affected 

3,033 mi of streams, 57,999 acres of lakes, and 59 mi of Great 

Lakes shoreline in the Indiana (Indiana Department of Environmental Management, 2004). Each year, some 833,000 resi  Mercury in Precipitation in Indiana, January 2001–December 2003
dent anglers 16 years and older spend 15.5 million days and 

$469 million for fishing as recreation. An estimated 286,000 

more resident anglers were 6 to 15 years old (U.S. Department 

of the Interior, 2003). Based on these numbers, fish-consumption advisories affect approximately 1 of 6 Indiana residents.2

Mercury in the Atmosphere

The forms and behavior of atmospheric mercury are complex, as explained by Schroeder and Munthe (1998), Lin and 

Pehkonen (1999), and Cohen and others (2004). Atmospheric 

mercury occurs in three forms—elemental, oxidized, and 

particulate-bound. Elemental mercury is more than 90 percent 

of the total mercury in the atmosphere. It is volatile, minimally 

water soluble3 and becomes globally distributed because it can 

last as long as 1 year in the atmosphere. Oxidized mercury can 

have a reactive gaseous form, can be a compound such as mercuric chloride, or can be dissolved in water droplets. Oxidized 

mercury makes up a few percent of the total mercury in the 

atmosphere but constitutes most of the mercury in atmospheric 

deposition. It is the most water soluble2 of the three forms and 

is more readily removed from the atmosphere than is elemental mercury. Oxidized mercury lasts 1 week or less in the 

atmosphere and generally is dispersed locally near its sources. 

Some atmospheric elemental mercury can become oxidized 

mercury and some oxidized mercury can become elemental 

mercury by reactions with other atmospheric chemicals and 

physical processes. Particulate-bound mercury is oxidized 

mercury such as mercuric oxide that is reversibly adsorbed to 

atmospheric particles (soot, dust, and ash.) Particulate-bound 

mercury constitutes a few percent of the total mercury in the 

atmosphere. It is relatively short-lived (1 to 2 weeks) and 

generally is dispersed locally near its sources. Particulatebound mercury can contribute to atmosphere deposition and 

can desorb from atmospheric particulates by chemical and 

physical processes.

Atmospheric mercury can be transported to aquatic 

or terrestrial ecosystems through wet deposition and dry 

deposition. Wet deposition of atmospheric mercury is the 

transfer of oxidized and particulate-bound mercury to the 

water and land in precipitation (rain, snow, sleet, hail, and 

fog). Mercury has been detected in precipitation throughout 

North America since monitoring began in 1996 (Sweet and 

Prestbo, 1999; National Atmospheric Deposition Program, 

2004). Often, mercury concentrations in precipitation exceed 

the water-quality criterion for a continuous freshwater 

concentration, 12 ng/L (U.S. Environmental Protection 

2

The sum of 833,000 Indiana resident anglers over 16 years in age and 

an estimated 286,000 resident anglers 6 to 15 years in age is approximately 

1 million Indiana anglers out of 6.2 million Indiana residents (Indiana Business Research Center, 2004).

3

The water solubility of elemental mercury is 49.4 x 10-6 grams per liter; the 

water solubility of oxidized mercury (as mercuric chloride, HgCl2) is 66 grams 

per liter (Schroeder and Munthe, 1998).

Agency, 1999a). Mercury wet deposition is better documented 

and better understood than mercury dry deposition, primarily 

because methods for measurement of wet deposition were 

developed earlier than those for dry deposition. 

As summarized by Grigal (2002), dry deposition of 

atmospheric mercury is a combination of oxidized mercury 

transfer onto and into vegetation, particulate-bound mercury 

transfer by gravity and air turbulence, and elemental mercury 

incorporation into foliage. Atmospheric deposition of mercury to forests is about four times that to water or open areas 

in the same geographic location because of dry deposition to 

foliage and mercury accumulation in forest leaves and needles. 

Mercury dry deposition generally is not measured directly and 

national monitoring programs to estimate dry deposition were 

still in development in 2006.

The Mercury Cycle 

Atmospheric mercury can enter lakes and streams 

directly or in stormwater runoff. Once in surface water (fig. 1), 

inorganic mercury enters a complex cycle in which one form 

can be converted to another, as explained by Krabbenhoft 

and Rickert (1995). Inorganic mercury in the water can enter 

sediments by particle settling and later can be released into the 

water by diffusion or resuspension. Mercury in the water can 

be released back to the atmosphere by volatilization and later 

can redeposit to water. Studies have shown that higher acidity 

and dissolved organic carbon levels in the water enhance the 

mobility of mercury, thus making it more likely to enter the 

food chain. The way mercury enters the food chain is not fully 

understood and probably varies among ecosystems. Studies 

have shown that bacteria that process sulfate in the environment take up inorganic mercury and metabolically convert it 

to methylmercury. The conversion of inorganic mercury to 

methylmercury is important because methylmercury is more 

toxic than inorganic mercury, and organisms require a longer 

time to eliminate methylmercury. Methylmercury-containing 

bacteria may be consumed by the next higher level in the food 

chain, or the bacteria may release the methylmercury to the 

water where it can adsorb quickly to plankton. Plankton then 

are consumed by the next level in the food chain. The concentration of methylmercury magnifies in organisms at higher 

levels in the food chain. Some methylmercury can convert 

back to inorganic mercury or enter sediments by particle settling. Many of the details of the aquatic-mercury cycle are still 

unknown, however, and are areas of active research.

Mercury in the Environment   
VOLATILIZATION and

RE-DEPOSITION

INORGANIC MERCURY

SEDIMENTATION

METHYLATION

METHYLMERCURY FOOD-CHAIN MAGNIFICATION

ATMOSPHERIC DEPOSITION 

OVERLAND RUNOFF

METHYLMERCURY

SEDIMENTATION

DE-METHYLATION

OUTFLOW POINT-SOURCE DISCHARGE STORMWATER DISCHARGE 

WET DEPOSITION

DRY DEPOSITION

GROUND-WATER DISCHARGE 

INORGANIC MERCURY METHYLMERCURY

METHYLATION

DE-METHYLATION

 DIFFUSION and

RE-SUSPENSION

Figure 1. Sources of mercury and mercury cycling in aquatic ecosystems (modified from Krabbenhoft and Rickert 1995). 

Sources of Mercury 

Sources of atmospheric mercury can be emissions from 

human activity or natural processes. Emissions from human 

activity come from stationary sources, such as coal combustion, waste incineration, steel mills, metal smelting, and 

refining, and from mobile sources (Seigneur and others, 2004; 

Schroeder and Munthe, 1998). Some mercury in aquatic 

ecosystems comes from point-source discharges of industrial 

and municipal wastewater and stormwater. Natural processes 

that cause mercury emissions are wildfires, volcanoes, and 

geothermal sources, plus re-emission or evasion from soil, 

vegetation, and water bodies (Schroeder and Munthe, 1998). 

Atmospheric deposition can contribute mercury directly to 

lakes and streams.

Information regarding stationary sources and estimated 

annual mercury emissions to the atmosphere was summarized 

from the 2001 Regional Air Pollutant Inventory Development 

System (RAPIDS) data for Indiana (Indiana Department of 

Environmental Management, Office of Planning and Assessment, 2004, written commun.). The 2001 RAPIDS data 

include emissions reported by the owner or operator of the 

stationary source. Emissions from electric-power plants were 

calculated with an emission factor (for the type of coal and 

type of electric-power plant) multiplied by the amount of coal 

used as fuel. 

 Mercury in Precipitation in Indiana, January 2001–December 2003
An estimated total of at least 7,487 lb of mercury were 

released to the atmosphere from stationary sources in Indiana 

in 2001. These sources were mostly electric-power plants, 

foundries, and steel mills (table 1). The 22 individual stationary sources with the highest annual mercury emissions for 

Indiana (more than 100 lb) included 14 electric-power plants, 

1 foundry, 1 coke oven, 3 cement facilities, 2 hospitals, and 

1 refinery.

Coal-fueled electric-power plants account for 94 percent 

of Indiana’s power generation (Indiana Department of Commerce, 2002). Indiana’s power plants rank eighth in the nation 

for electricity sales and Indiana is a net exporter of electricity. 

These power plants consume nearly 59 million tons of coal 

per year. In 2001, approximately 38 million tons of coal were 

produced in Indiana. Most of this coal was used by electric 

utilities in the State. In Indiana and the surrounding states of 

Ohio, Kentucky, Illinois, and Michigan, 115 coal-fueled electric-power plants emitted nearly 26,400 pounds of mercury in 

2000 (U.S. Environmental Protection Agency, 2004). 

Mercury Monitoring in Indiana

Prior to 2001, few data were available that provided 

information about the atmospheric deposition of mercury in 

Indiana, partly because the scientific methods to reliably measure mercury in precipitation were relatively new (U.S. Environmental Protection Agency, 1997a) and partly because 

a national mercury-monitoring network was relatively new

(Sweet and Prestbo, 1999). Also, prior to 2001, most of the 

atmospheric deposition of mercury was believed to be from 

precipitation (U.S. Environmental Protection Agency, 1997a) 

and accepted methods for monitoring dry deposition had not 

been developed.

The IDEM Mercury Work Group was organized in 1999 

as a team of managers and technical personnel from IDEM’s 

programs for planning and assessment, air quality, water quality, land quality, and pollution prevention. The IDEM Mercury 

Work Group, with scientists from the USGS, determined that 

the geographic distribution and trends in the atmospheric 

deposition of mercury could not be quantified in Indiana without a monitoring program. In 2000, mercury in precipitation 

(which causes mercury wet deposition) was selected for the 

initial study in Indiana because reliable methods for sampling 

and analysis were available through a national network. The 

USGS implemented the monitoring program for mercury in 

precipitation in Indiana (hereafter in this report, the “monitoring program”), starting in late 2000, in cooperation with the 

IDEM Office of Air Quality and Office of Water Quality. 

The monitoring program is part of the Mercury Deposition Network (MDN) that was started in 1996 and coordinated through the National Atmospheric Deposition Program 

(NADP). The NADP is a consortium of federal agencies 

(including the USGS), state agencies, academic institutions, 

tribal governments, and private organizations in the United 

States and the environmental agencies in Canada. For more 

than 25 years, NADP has provided consistent, accurate, quality-assured atmospheric-deposition data about acid rain to 

researchers, policy makers, and the general public (National 

Atmospheric Deposition Program, 2004).

Table 1. Stationary sources and estimated annual mercury emissions to the atmosphere in Indiana in 2001. 

Category

Pounds of 

mercury 

emissionsa

Number of 

emission 

sourcesa

Percentage of 

all mercury 

emissions from 

stationary 

sources in 

Indianaa

Range of annual

emission rates 

per source

(pounds)a

Electric-power plants 4,565 33 61 0.13 – 942

Foundries and steel mills (including coke ovens) 1,170 22 15.6 .02 – 720

Cement and gypsum production facilities 729 9 9.7 .21 – 240

Industries, manufacturing, and petroleum refineries 611 43 8.2 .01 – 237

Hospitals and medical-waste incinerators 377 18 5.0 .01 – 215

Paving and asphalt plants 27 18 .4 .01 – 14

Natural gas pipeline operations 8 10 .1 .07 – 3

a

Number of emission sources and annual mercury emissions from 2001 Regional Air Pollutant Inventory Development System for Indiana (Indiana 

Department of Environmental Management, Office of Planning and Assessment, 2004, written commun.), and includes only the sources that reported 

mercury emissions for the 2001 inventory.

Mercury in the Environment 
Objectives of the monitoring program that were identified 

by the IDEM Mercury Work Group apply to mercury concentrations in precipitation and to mercury wet deposition.

Obtain baseline information before and after 

implementation of regulatory controls on mercury 

emissions.

Determine if the geographic distribution of mercury is uniform or if local emissions sources have 

an effect.

Observe seasonal or annual trends in mercury.

Obtain mercury data that can be compared with 

that of other states.

The mercury-monitoring data for 2001 through 2003 in 

this report constitute a baseline of information for comparison with future data in Indiana and the NADP-MDN data 

from other states. Emissions controls for air pollutants such 

as nitrogen oxides, sulfur dioxides, ozone, fine particulates, 

and mercury will be required at some mercury-emissions 

sources through implementation of Federal and State rules 

under authority of the Clean Air Act, particularly the Clean 

Air Interstate Rule (Code of Federal Regulations, 2005a) 

and the Clean Air Mercury Rule (Code of Federal Regulations, 2005b). A long-term, consistent monitoring program 

for mercury in precipitation in Indiana has the capability of 

detecting changes in mercury concentrations in precipitation 

and mercury wet deposition that may result from the emissions 

controls required by these rules.

Study Methods

The monitoring program in Indiana is part of a large-scale 

network in North America that has a uniformity in procedures 

•

•

•

•

and instrumentation which makes the data inter-comparable. 

The monitoring locations in Indiana were selected by the 

IDEM Mercury Work Group and are described in this section. 

Precipitation was sampled, measured, and analyzed for mercury at these locations, using the techniques that are explained 

in this section. The approach for quality-assurance, management, and reporting of the data from the monitoring program 

are presented as well.

Selection of Monitoring Locations

Four locations in Indiana were used by the USGS and 

IDEM for the monitoring program, 2001–2003, and are part of 

the NADP-MDN. As of January 2001, there were 42 NADPMDN monitoring locations in North America; this number 

grew to 79 by spring 2003 (fig. 2). Locations in the NADPMDN are regionally representative and are not intended to 

evaluate the atmospheric mercury associated with a specific 

emissions source. The monitoring locations in Indiana met the 

NADP-MDN siting criteria. The criteria include restrictions 

for minimum separation distances of 1,640 ft from combustion 

sources and highways and 328 ft from metal-working facilities, roads, waterways, runways, parking lots, maintenance 

yards, and fuel storage. The monitoring equipment at a location must be separated from nearby trees, buildings, towers, or 

structures by a distance greater than twice their height.

The four locations for the monitoring program were 

selected by the IDEM Mercury Work Group (fig. 3). Two 

existing NADP monitoring locations and two new locations 

were chosen to represent four geographic regions and four 

major watersheds (table 2). 

Table 2. Characteristics of monitoring stations for mercury in precipitation in Indiana.

[NADP, National Atmospheric Deposition Program]

Abbreviated

station name

Station

number

Latitude / longitude

(degrees, minutes, 

seconds)

Geographic region Major

watersheda

Land-use

setting

Normal

annual

precipitation 

(inches)b

2001 annual

mercury 

emissions

(pounds)c

Roush Laked IN20 40o50’24” / 85o27’50” Northeastern Indiana Wabash River Rural 37.21 252

Clifty Falls IN21 38o

45’42” / 85o25’12” Southeastern Indiana; 

Ohio River Valley

Ohio River Suburban 44.97 1,628

Bloomington IN28 39o

08’46” / 86o36’48” South-Central Indiana White River Suburban 46.79 141

Indiana Dunesd IN34 41o

37’55” / 87o05’16” Northwestern Indiana; 

Lake Michigan shore

Lake Michigan Suburban 38.56 1,878

a

Watershed boundaries are shown in figure 3.

b

Normal is for 1971 through 2000 (Purdue Applied Meterorology Group, 2005).

c

Annual mercury emissions from stationary sources within 31 miles of the monitoring station were based on the 2001 Regional Air Pollutant Inventory System 

for Indiana (Indiana Department of Environmental Management, written commun., 2004) and the 2000 Emissions and Generation Resource Integrated Database 

(U.S. Environmental Protection Agency, 2004) for sources on the Kentucky-Indiana border.

d

Location of National Atmospheric Program National Trends Network monitoring station.

 Mercury in Precipitation in Indiana, January 2001–December 2003
Figure 2. Locations of National Atmospheric Deposition Program Mercury Deposition Network monitoring stations in North America, spring 2003 (modified from 

National Atmospheric Deposition Program, 2004). 

Study Methods 
Lake Michigan Watershed

Ohio River Watershed

Wabash River Watershed

White River Watershed

LAGRANGE STEUBEN

ELKHART ST JOSEPH

LAKE PORTER

LA PORTE

NOBLE DE KALB

MARSHALL

KOSCIUSKO STARKE

WHITLEY

ALLEN

JASPER

NEWTON

PULASKI FULTON

WABASH HUNTINGTON

MIAMI

ADAMS

WELLS

WHITE CASS

BENTON CARROLL

GRANT JAY BLACK

FORD HOWARD

TIPPECANOE WARREN

CLINTON TIPTON

DELAWARE

MADISON

FOUNTAIN

RANDOLPH

MONTGOMERY HAMILTON BOONE

VERMILLION

HENRY

WAYNE

HANCOCK

PARKE MARION HENDRICKS

PUTNAM FAYETTE

RUSH

UNION

SHELBY MORGAN JOHNSON

VIGO CLAY

FRANKLIN

OWEN DECATUR MONROE BROWN BARTHOLEMEW

RIPLEY

DEARBORN

SULLIVAN

JENNINGS

GREENE

JACKSON OHIO

LAWRENCE JEFFERSON SWITZERLAND

KNOX DAVIES MARTIN SCOTT

WASHINGTON

ORANGE

CLARK

PIKE

GIBSON

DUBOIS CRAWWFORD

HARRISON

FLOYD

WARRICK PERRY

POSEY SPENCER VANDERBURGH

Lake Michigan

Roush Lake

 Indiana Dunes

Bloomington

Clifty Falls

EXPLANATION

Monitoring station

National Atmospheric Deposition

Program Mercury Deposition 

Network station number

 Indiana Dunes

IN34

IN34

IN20

IN28

IN21

Monitoring station name

Figure 3. Monitoring locations for mercury in precipitation in Indiana, 2001–2003. 

 Mercury in Precipitation in Indiana, January 2001–December 2003
Four monitoring stations for mercury in precipitation in 

Indiana (hereafter in this report, “monitoring station” or “four 

monitoring stations”) were established in late 2000–early 2001 

at: Roush Lake in Huntington County, Clifty Falls in Jefferson 

County, Bloomington in Monroe County, and Indiana Dunes 

in Porter County.

The Roush Lake monitoring station is collocated with 

a station of the NADP National Trends Network (NTN) for 

acid-rain monitoring. It is south of Huntington and more than 

12 mi from any stationary sources of more than 0.1 lb/yr of 

mercury emissions to the atmosphere (fig. 4). The Roush Lake 

location was selected because of its rural setting and isolation 

from sources of high annual mercury emissions. The Clifty 

Falls monitoring station is near Madison, less than 2.5 mi from 

a coal-fueled electric-power plant in Indiana and within 19 mi 

of two coal-fueled electric-power plants in Kentucky (fig. 5). 

The Clifty Falls location was selected because of its high 

annual precipitation for Indiana and its position in the Ohio 

River Watershed northeast and southwest from sources of 

high annual mercury emissions. The Bloomington monitoring 

station is more than 4.3 mi from two small (less than 5 lb/yr) 

stationary sources of mercury emissions to the atmosphere 

(fig. 6). The Bloomington location was selected because of its 

high annual precipitation for Indiana and its potential position 

downwind from sources of high annual mercury emissions in 

southwestern Indiana. The Indiana Dunes monitoring station 

is collocated with an NTN station of the NADP. It is near 

Porter, less than 2.5 mi from a coal-fueled electric-power plant 

and within 31 mi of at least 30 stationary sources of mercury 

emissions to the atmosphere (fig. 7). The Indiana Dunes location was selected because of the proximity to Lake Michigan 

and its tributaries that have fish-consumption advisories for 

mercury.

Instrumentation of Monitoring Stations

The four monitoring stations in Indiana were instrumented the same as other monitoring stations in the NADPMDN—with an automated precipitation sampler and a 

recording rain gage. The automated precipitation sampler was 

an Aerochem Metrics Model 301, modified with an insulated 

sample-storage enclosure and internal heating and ventilation 

to operate year round (fig. 8). A conductivity-grid sensor on 

the sampler activated a motor when precipitation was falling. 

The motor opened a retractable lid over a chimney that held 

a sampling train supported on an adjustable stand (fig. 9). 

Sampling supplies were prepared and quality assured at the 

NADP-MDN laboratory. The pre-cleaned sampling train 

consisted of a glass funnel connected by a glass capillary tube 

to a pre-weighed and tared 2,000-mL glass sample bottle. 

The sample bottle contained 20 mL of 1-percent high-purity 

hydrochloric acid as a preservative. When the sampler lid was 

open and the funnel of the sampling train was exposed, liquid 

precipitation falling into the funnel was collected in the bottle. 

In cold weather, a thermostat-controlled heater in the insulated 

enclosure caused heated air to rise around the glass funnel 

in the chimney to melt frozen precipitation in the funnel. A 

heated pad beneath the conductivity-grid sensor dried the grid 

when precipitation ceased, activating the motor to close the 

retractable lid and seal the chimney. 

Precipitation was measured with a Belfort model 5-780 

universal, weighing-bucket, recording rain gage (fig. 10). 

Cumulative precipitation was recorded as a continuous pen 

trace on a paper chart mounted on a revolving drum controlled 

by a mechanical clock. Openings and closings of the sampler 

were marked on the chart with an event-recorder pen activated 

by an electric pulse from the sampler. A funnel inside the 

rain-gage chimney served as a lid that minimized evaporation 

of precipitation in hot weather. In cold weather, the funnel was 

removed and antifreeze was added to the bucket to promote 

retention and melting of frozen precipitation. 

The Belfort 5-780 rain gage was evaluated in a 26-week 

field study in 1999 at the USGS Hydrologic Instrumentation Facility in Bay St. Louis, Miss., (Gordon, 2003) during 

which precipitation greater than 0.01 in. occurred each week. 

Accuracy of two Belfort 5-780 rain gages was measured as 

a -0.01-in. median relative difference to a National Weather 

Service stick-type gage, a difference that was not statistically 

significant. Precision of the two Belfort 5-780 rain gages was 

measured as 0.00-in. median relative difference, which was 

not statistically significant.

Collection and Analysis of Precipitation 

Samples

The sampling train (funnel, bottle, and capillary tube) 

was exchanged every Tuesday, following a uniform procedure (Longley and Brunette, 2003) and a schedule used at all 

NADP-MDN stations. Therefore, a weekly sample may have 

contained a single precipitation event4

 or it may have been a 

composite of two or more precipitation events. Weekly precipitation samples were analyzed by the NADP-MDN laboratory, Frontier Geosciences, Inc., in Seattle, Wash., to maintain 

consistency and comparability of results. Other descriptions 

of the sampling, analytical, and quality-assurance procedures 

are in Lindberg and Vermette (1995), Vermette and others 

(1995), Sweet and Prestbo (1999), and Lehmann and Bowersox (2003). 

4

In this report, single precipitation events are defined as those separated by 

a break of 8 hours or more in precipitation accumulation.

Study Methods 
ALLEN

JAY

MIAMI

GRANT

WELLS

WABASH

ADAMS

KOSCIUSKO WHITLEY

HUNTINGTON

HOWARD BLACKFORD

Roush Lake 

(IN20)

Huntington

Roush Lake 

(IN20)

86°0' 85°0'

40°30'

41°0'

Circle indicates the location of a stationary mercury-emissions source, based on data

from the 2001 Regional Air Pollutant Inventory System for Indiana (Indiana Department 

of Environmental Management Office of Air Quality, written commun., January 2004). 

Annual mercury emissions (in pounds) for each source are in a range indicated by the 

size of the circle, according to the following scale:

0.1 to 10 10.1 to 50 50.1 to 100

100.1 to 200 greater than 200

Monitoring station with National Atmospheric Deposition 

Program Mercury Deposition Network station number

EXPLANATION

Base from U.S. Geological Survey digital data 1:100,000, 1983. 

Universal Transverse Mercator projection, zone 16, NAD 83 0 5 15 KILOMETERS

0 5 10 15 MILES

10

Figure 4. Roush Lake monitoring station for mercury in precipitation in Indiana, with nearby stationary sources of 

mercury emissions. 

10 Mercury in Precipitation in Indiana, January 2001–December 2003
Circle indicates the location of a stationary mercury-emissions 

source, based on data from the 2001 Regional Air Pollutant 

Inventory System for Indiana (Indiana Department of Environmental 

Management Office of Air Quality, written commun., January 2004);

Kentucky data from the 2000 Emissions and Generation Resource

Integrated Database (U.S. Environmental Protection Agency, 2004).

Annual mercury emissions (in pounds) for each source are in a 

range indicated by the size of the circle, according to the 

following scale:

0.1 to 10 10.1 to 50 50.1 to 100

100.1 to 200 greater than 200

RIPLEY

CLARK

JENNINGS

JACKSON

JEFFERSON

SCOTT

DEARBORN BARTHOLOMEW

FLOYD

OHIO

SWITZERLAND

Clifty Falls 

(IN21)

INDIANA

KENTUCKY

WASHINGTON

Clifty Falls 

(IN21)

Madison

86°0' 85°0'

38°30'

39°0'

Base from U.S. Geological Survey digital data 1:100,000, 1983. 

Universal Transverse Mercator projection, zone 16, NAD 83 0 5 15 KILOMETERS

0 5 10 15 MILES

10

Monitoring station with National Atmospheric 

Deposition Program Mercury Deposition Network 

station number

EXPLANATION

Figure 5. Clifty Falls monitoring station for mercury in precipitation in Indiana, with nearby stationary sources of 

mercury emissions. 

Study Methods 11
CLAY

GREENE

OWEN

MONROE

MORGAN

JACKSON

BROWN

DAVIESS

LAWRENCE

MARTIN

PUTNAM

JOHNSON

WASHINGTON

BARTHOLOMEW

KNOX

Bloomington

(IN28)

87°0' 86°0'

39°0'

39°30'

0 5 15 KILOMETERS

0 5 10 15 MILES

10

EXPLANATION

Base from U.S. Geological Survey digital data 1:100,000, 1983. 

Universal Transverse Mercator projection, zone 16, NAD 83 

Monitoring station with National Atmospheric Deposition 

Program Mercury Deposition Network station number

Circle indicates the location of a stationary mercury-emissions source, based on data

from the 2001 Regional Air Pollutant Inventory System for Indiana (Indiana Department 

of Environmental Management Office of Air Quality, written commun., January 2004). 

Annual mercury emissions (in pounds) for each source are in a range indicated by the 

size of the circle, according to the following scale:

0.1 to 10 10.1 to 50 50.1 to 100

100.1 to 200 greater than 200

Bloomington

(IN28)

Bloomington

Figure 6. Bloomington monitoring station for mercury in precipitation in Indiana, with nearby stationary sources of mercury 

emissions. 

12 Mercury in Precipitation in Indiana, January 2001–December 2003
Study Methods 13

Figure 7. Indiana Dunes monitoring station for mercury in precipitation in Indiana, with nearby stationary sources of mercury 

emissions. 

LAKE

PORTER

LA PORTE

STARKE

JASPER

ST JOSEPH

Indiana Dunes 

(IN34)

Lake Michigan

ILLINOIS

INDIANA

EXPLANATION

Base from U.S. Geological Survey digital data 1:100,000, 1983.

Universal Transverse Mercator projection, zone 16, NAD 83

0 5 15 KILOMETERS

0 5 10 15 MILES

10

Monitoring station with National Atmospheric Deposition 

Program Mercury Deposition Network station number

Circle indicates the location of a stationary mercury-emissions source, based on data

from the 2001 Regional Air Pollutant Inventory System for Indiana (Indiana Department 

of Environmental Management Office of Air Quality, written commun., January 2004). 

Annual mercury emissions (in pounds) for each source are in a range indicated by the 

size of the circle, according to the following scale:

0.1 to 10 10.1 to 50 50.1 to 100

100.1 to 200 greater than 200

Indiana Dunes 

(IN34)

Porter

87°30' 86°30'

41°30'

41°15'
Thermostats

for fan and heater

Heater

Cooling fan

and vent

Insulated enclosure

Filtered air inlet

Glass sample bottle

Glass capillary tube

Glass funnel

Mercury sampling train:

Mercury sampler chimney

Support for

retracted lid

Retractable lid and Teflon-covered

fiberglass-cloth sealing pad

Adjustable stand

Conductivity-grid sensor

Motor and controller

for retractable lid

Second sampler chimney

Figure 8. Automated precipitation 

sampler at monitoring station for 

mercury in precipitation in Indiana. 

Figure 9. Diagram of automated precipitation sampler at monitoring station for mercury in precipitation in Indiana 

(modified from Lindberg and Vermette, 1995). 

14  Mercury in Precipitation in Indiana, January 2001–December 2003
A monitoring station was serviced by the same field 

personnel each week, who used a kit of sampling supplies 

prepared by the NADP-MDN laboratory. Field personnel wore 

new, powder-free vinyl gloves when removing the exposed 

sampling train. The bottle was capped, inspected, bagged, and 

placed in a shipping container with the used funnel and capillary tube. New gloves were worn to assemble and install a new 

sampling train in the sampler. A new paper chart was installed 

on the rain gage and sample information was recorded on the 

paper field form. The sampling train, rain-gage chart, and field 

form were shipped to the NADP-MDN laboratory. The USGS 

retained copies of the charts and forms.

At the NADP-MDN laboratory, the sample bottle was 

weighed and the sample volume determined. An aliquot was 

obtained from the sample bottle for analysis of total mercury. 

If more than 0.08 in. of precipitation (equivalent to 25 mL) 

was in the sample bottle, a separate aliquot was obtained for 

analysis of methylmercury. 

Total mercury was analyzed by Method 1631 (U.S. Environmental Protection Agency, 1999b), a low-level method with 

a detection limit at the NADP-MDN laboratory of 0.05 ng/L. 

In this method, total mercury was separated from the water 

by oxidation with bromium chloride and reduction with 

tin chloride, followed by thermal desorption and dual gold trap 

amalgamation. Mercury then was quantified by cold vapor 

atomic fluorescence spectrometry. 

Methylmercury was analyzed by Method 1630 

(U.S. Environmental Protection Agency, 1997b), a low-level 

method with a detection limit at the NADP-MDN laboratory 

of 0.002 ng/L. In this method, methylmercury was separated 

from the water by distillation and aqueous ethylation, followed 

by thermal desorption and dual gold trap amalgamation. 

Methylmercury then was quantified by cold vapor atomic 

fluorescence spectrometry. 

Quality Assurance

Quality assurance (QA) was implemented through routine 

procedures, routine computations, on-site audits and calibration checks, field and laboratory quality-control data, and a 

data-review sequence. Programs and procedures for QA of 

network operations, laboratory services, and data management 

for the NADP-MDN are described in a comprehensive quality 

management plan (Lehmann and Bowersox, 2003). For the 

monitoring program in Indiana, QA was provided for the rain 

gage, precipitation sampler, field procedures, monitoring station, laboratory analysis, and monitoring data. 

Rain gage QA included quarterly field calibration checks, 

the computed capture efficiency for each sample, comparisons 

with alternate rain gages, a third-party audit of the rain gage, 

and routine maintenance procedures. Each quarter, a set of 

calibrated weights were used to check the accuracy of the rain 

gage at each station. The NADP-MDN laboratory provided 

reminders and instructions each quarter. Field personnel made 

a chart of the calibration check and submitted it to the laboratory. If the calibration check had identified an inaccurate gage, 

field personnel would have recalibrated the gage. 

Capture efficiency was computed for each sample as 

the ratio of the precipitation amount in the sample bottle 

compared to precipitation amount recorded by the rain gage. 

Capture efficiency was reported with the preliminary analytical data each quarter as a measure of whether a rain-gage 

malfunction was causing greater than 100-percent capture. If 

a rain gage malfunction had been indicated with the capture 

efficiency, field personnel would have been inspected and corrected the gage. 

Alternate rain gages were available for the monitoring 

stations: a standard stick gage at Roush Lake and Clifty Falls, 

a recording rain gage at Bloomington and Indiana Dunes. Data 

from the alternate gage was compared each week against data 

from the Belfort recording rain gage as a quality-assurance 

check. If a Belfort rain-gage malfunction had been indicated, 

field personnel would have inspected and corrected the gage. 

At least every 3 years, a third party audit is performed 

at each station, contracted for the NADP-MDN by the 

U.S. Environmental Protection Agency. The four stations in 

Indiana were audited by ATS, Inc., in May 2003. A rain-gage 

calibration check and inspection were part of this audit. 

Figure 10. Recording rain gage at monitoring station for 

mercury in precipitation in Indiana. 

Study Methods 15
The audits gave satisfactory ratings of the four rain gages in 

Indiana. If any rain-gage problems had been identified with 

the audit, they would have been corrected at that time. 

Last, the NADP-MDN laboratory provided seasonal 

reminders and instructions for summer and winter maintenance of the rain gage, along with instructions for periodic 

cleaning of the internal mechanism of the rain gage. The maintenance and cleaning of the rain gage helped assure accurate 

and consistent precipitation data.

Precipitation sampler QA included inspection of the 

event recorder pen trace, the computed capture efficiency, 

and a third-party audit. The event-recorder pen trace on the 

rain-gage chart was inspected weekly to determine whether 

the precipitation sampler opened during precipitation only. If 

the precipitation sampler malfunctioned, based on the event 

recorder, a troubleshooting procedure was used to correct 

and test the sampler before the following week’s sample. The 

computed capture efficiency for each sample (the ratio of the 

precipitation amount in the sample bottle compared to precipitation amount recorded by the rain gage) was used to evaluate 

the function of the precipitation sampler. Repeated capture 

efficiency less than 75 percent would have indicated that the 

sampler needed to be inspected and a malfunction corrected. 

Quantitative evaluations of the precipitation sampler sensor, 

motor, seal, height, and orientation were completed during the 

third-party audit in May 2003. The audits gave satisfactory ratings of the four precipitation samplers in Indiana.

Field procedures QA included a third-party audit and 

standard operating procedures (Longley and Brunette, 2003). 

During the third-party audit in May 2003, all of the routine 

field procedures for a weekly sample were witnessed by the 

audit team who evaluated compliance with the written standard operating procedures. Written reports of the audits were 

provided and discussed with USGS personnel and filed with 

the NADP-MDN Program Office. The audits gave satisfactory 

ratings of field procedures in Indiana.

Monitoring station QA included an on-site inspection by 

personnel from the NADP Program Office. At least once during 2001–2003, the location, configuration, and installation of 

the precipitation sampler and the rain gage were checked for 

compliance with the NADP-MDN siting criteria. Data from 

the inspections are available from an on-line archive 

(http://nadp.sws.uiuc.edu/nadpdata/mdnsites.asp).

Laboratory analysis QA included field and laboratory 

quality-control data. Field quality-control data were obtained 

from 15 field bottle blanks. The preservative was analyzed 

for total mercury when the event recorder documented that 

the sampler did not open the entire week and there was no 

recorded precipitation. Mercury was not detected in these 

15 samples, indicating a pattern of sample bottle preparation 

and sample handling that did not introduce mercury contamination (appendixes 1-1 through 1-4).

The following laboratory quality-control data were used 

to assure laboratory analyses of total mercury concentrations 

were within control limits: correlation coefficients of calibration standards, percent recoveries of standard reference 

materials, relative percent differences of duplicate samples, 

percent recoveries of matrix-spike samples, relative percent 

differences of matrix-spike duplicate samples, concentrations 

in reagent blanks, and concentrations in laboratory bottle 

blanks. Laboratory quality-control samples (appendix 2-1) 

were analyzed at a rate of 4 for every 10 precipitation samples. 

If trace amounts of total mercury were detected in laboratory 

bottle blank samples, the quarterly mean of the bottle blanks 

was subtracted as a blank correction in calculation of the 

sample concentration.

Monitoring data QA included a multi-step data-review 

sequence. The daily and weekly precipitation amounts were 

computed from the rain-gage chart by field personnel and 

recorded on the field-data form. At the NADP-MDN laboratory, the precipitation amounts were reviewed and entered into 

preliminary data. Once each quarter, the laboratory sent the 

preliminary data to the USGS for verification of precipitation, 

mercury concentration, and mercury wet deposition values, 

along with information recorded on the field-data forms. After 

the preliminary data were revised and verified by the NADPMDN laboratory, the data were sent to the NADP-MDN Program Office for review and verification before being finalized 

and posted in the NADP-MDN on-line archive 

(http://nadp.sws.uiuc.edu/nadpdata/mdnsites.asp).

Data Management and Reporting

The following information was recorded on the field-data 

form for each weekly sample at a monitoring station: 

starting and ending dates and times of the sampling period (typically Tuesday through Tuesday); 

type of precipitation (rain, snow, or mixed rain 

and snow) each day;

type of sample (wet, dry, trace, or quality control); 

amount of precipitation each day (in.), including 

zero or trace (<0.01 in.) amounts; and

comments on equipment and field activities.

The following data were reported by the NADP-MDN 

laboratory for each weekly sample at a monitoring station:

precipitation (mm and in.) in the rain gage; 

precipitation (mm and in.) in the sample bottle; 

sample volume (mL) in the sample bottle;

total mercury concentration (ng/L) in the sample;

methylmercury concentration (ng/L) in the 

sample;

total mercury wet deposition (ng/m2

), a computed 

value; 

•

•

•

•

•

•

•

•

•

•

•

16  Mercury in Precipitation in Indiana, January 2001–December 2003
methylmercury wet deposition (ng/m2

), a computed value;

data-quality rating and associated qualifier codes; 

and

comments from the NADP-MDN laboratory.

Four types of weekly samples were reported. 

Wet-deposition sample—more than 0.01 in. of 

precipitation was recorded by the rain gage or 

more than 10 mL of precipitation were collected 

in the sample bottle. 

Trace sample—the event recorder on the rain gage 

indicated the precipitation sampler opened 1 or 

more times; or 1.5 to 10 mL of precipitation were 

collected in the sample bottle; a mercury concentration was not reported.

Dry sample—the event recorder on the rain gage 

indicated the sampler did not open; less than 

0.01 in. of precipitation was recorded by the rain 

gage or less than 1.5 mL of precipitation in the 

sample bottle; a mercury concentration was not 

reported. 

Quality-control (QC) sample—the event recorder 

on the rain gage indicated the sampler did not 

open; less than 0.01 in. of precipitation was 

recorded by the rain gage. The preservative in the 

sample bottle was analyzed and a mercury concentration was reported for a field bottle blank.

Wet deposition of mercury (hereafter in the report “mercury deposition”) was a mass per unit area per week computed 

with the weekly sample concentration, weekly precipitation 

amount from the rain gage, and equation 1: 

(1)

where

D = mercury deposition, in ng/m2,

C = mercury concentration, in ng/L, 

and

P = precipitation amount from the rain gage, 

in mm.

Units in equation 1 were converted with equation 2:

(2)

Precipitation amount for the weekly sample normally was 

measured with the rain gage at the monitoring station. If the 

precipitation sampler worked properly but the rain-gage data 

•

•

•

•

•

•

•

were missing or were incomplete, deposition was computed 

with the precipitation amount in the sample bottle in place 

of the rain gage. An alternate rain-gage amount was used, if 

available, to determine if the amount in the sample bottle was 

representative. 

Estimated deposition was computed if the sample concentration was missing and the rain gage measured the weekly 

precipitation. The sample concentration was missing if the 

precipitation sampler did not work properly (as indicated by 

the event recorder on the rain gage) or if there was a laboratory 

error. Estimated deposition was computed with equation 1 and 

the seasonal volume-weighted concentration in place of the 

missing sample concentration. The seasonal volume-weighted 

concentration was computed as the sum of the weekly volume-weighted concentrations during the 13-week season. 

The weekly volume-weighted concentration was computed 

with equation 3 and excludes trace, dry, and QC samples and 

samples that were missing a concentration.

(3)

where

WC = weekly volume-weighted concentration, 

in ng/L,

C = weekly concentration, in ng/L,

S = weekly sample volume, in mL, 

and

T = sum of weekly sample volumes (during 

13-week seasonal period), in mL.

Data for precipitation, sample volume, mercury concentration, and mercury deposition are grouped by season 

(quarter), based on the reporting schedule of the NADP-MDN 

laboratory. The seasons are 13 weeks each and are standardized as winter (January, February, and March), spring (April, 

May, and June), summer (July, August, September), and fall 

(October, November, December). 

Data-quality rating codes for each sample were assigned 

by the NADP-MDN laboratory:

A—no field or laboratory problems, data quality 

acceptable for summary statistics;

B—minor field or laboratory problems, data quality acceptable for summary statistics; or

C—field or laboratory problems, data quality 

suspect.

Samples with an A rating or B rating were included automatically among the data summarized in this report. Samples 

received a B rating if debris was visible in the sample, if the 

sample was low volume (1.5–10 mL), if the sample bottle had 

a small leak during transport, if the precipitation amount in the 

sample bottle rather than the rain gage was used to calculate 

deposition, or if sample information was missing or incomplete. 

•

•

•

D = C * P

WC = C * (S / T)

Study Methods 17

ng

L mm ngL

L

cm

cm

m mm m

mm

ng

m

* * , *

, , * * ,

=

=

1 000

1 000 000

1 000

3

3

3 2
Samples received a C rating for precipitation-sampler or 

rain-gage malfunction, an error in sample handling, or a laboratory error. Samples with a C rating5

 were included among 

the data summarized in this report if one of the following 

conditions was documented for the sample. 

The sampler did not open during some or all precipitation events, the rain gage worked correctly, and 

mercury deposition was estimated. 

The sample concentration was not reported because 

of a laboratory error, the rain gage worked correctly, 

and mercury deposition was estimated. 

The sampler had a malfunction or repair but worked 

properly during every precipitation event, the rain 

gage worked correctly, the sample amount was 

more than 80 percent of the rain gage precipitation 

amount, and the total mercury concentration and 

deposition were reported. 

Preliminary methylmercury concentrations and data-quality ratings were reported annually by the NADP-MDN laboratory to the USGS. After verification review by the USGS and 

any needed corrections by the laboratory, methylmercury 

deposition was computed with the final precipitation data from 

the NADP-MDN on-line archive, the final methylmercury 

concentrations, and equation (1). Any sample with less than 

0.08 in. precipitation had insufficient volume for a portion to 

be split for methylmercury analysis; total mercury analysis 

was given priority for small-volume samples. Other small-volume samples may have had insufficient volume for a methylmercury analysis to be completed. Methylmercury deposition 

was not computed for samples in which methylmercury was 

not detected, and methylmercury deposition was not estimated 

for any sample that had insufficient volume for methylmercury 

analysis. 

For this report, the final weekly sample data for the 

four monitoring stations (appendixes 1-1 through 1-4) were 

obtained from the NADP-MDN on-line archive and from 

the weekly field forms. Summary values were computed 

with those weekly data for three time periods: the 3-year 

study period, 2001–2003 (called a 3-year value), a 1-year 

period (called an annual value), or a 13-week period (called 

a seasonal value). The summary values were computed for 

individual monitoring stations and all four monitoring stations, 

and may include statistical descriptions of mean, median6

, 

minimum, maximum, or standard deviation. In this report, the 

summary values are:

5

Approximately 7 percent of the wet-deposition samples in this report have 

a C rating (appendixes 1-1 through 1-4). Total mercury deposition was derived 

from the precipitation in all of these samples, mostly as estimated deposition.

6

Median is the value that separates the rank-ordered data into two parts (for 

example, half of the concentrations are greater than the median and half of the 

concentrations are less than the median).

•

•

•

volume-weighted concentration, in ng/L, for total 

mercury—a sum of weekly volume-weighted 

concentration values;

cumulative deposition, in ng/m2 —a sum of 

weekly deposition values;

cumulative precipitation7, in in.—a sum of weekly 

precipitation values;

normalized deposition, in ng/m2/in.—cumulative 

deposition divided by cumulative precipitation

Mercury in Precipitation in Indiana

This section provides summary tables about the weekly 

samples, concentrations of total mercury and methylmercury, 

and deposition of total mercury and methylmercury for each 

monitoring station. Weekly values are compared with box 

plots, and annual values are presented in bar graphs. The variability of total mercury and methylmercury concentrations and 

deposition in Indiana and its relation to the NADP-MDN is 

examined statistically and presented in maps and bar graphs.

Weekly Samples

Weekly samples were attempted when sampling trains 

were installed at the four monitoring stations each week. 

Either wet-deposition samples were collected (rain, snow, or 

mixed rain and snow) or weekly samples without wet deposition were reported (trace, dry, or QC samples). During the 

3-year period, 626 sampling trains were installed and 551 wetdeposition samples were collected (88 percent of total); 

75 samples did not have wet deposition (table 3). Generally, 

the same number of sampling trains were installed at each station during the 3-year period (155 to 157), but the number of 

wet-deposition samples ranged from 131 to 143 samples. 

Overall, 78 percent of the wet-deposition samples were 

rain; the remainder were snow or mixed rain and snow. Monitoring stations at Indiana Dunes and Roush Lake in northern 

Indiana had at least 50 percent more snow and mixed rain and 

snow samples than the monitoring stations at Clifty Falls and 

Bloomington in southern Indiana. The number of precipitation events per sample were determined by visual inspection 

of the rain-gage charts for the wet-deposition samples. For 

purposes of this discussion, precipitation events are separated 

by a break of 8 hours or more in precipitation accumulation. 

For the 3-year period, weekly samples contained a mean of 

two events. The greatest number of weekly samples contained 

one event (206 samples), followed by two events (172 samples), three events (124 samples), and four to five events 

(49 samples).

7

Inches are used for precipitation amounts in this report because inches 

are a common unit for precipitation amounts in weather reports.

•

•

•

•

18  Mercury in Precipitation in Indiana, January 2001–December 2003
Table 3. Weekly samples at four monitoring stations for mercury in precipitation in Indiana, January 2001–

December 2003. 

[QC, quality-control]

Station name Year

Number of

sampling

trains

installeda 

Number of

wet-deposition

samples

Number of 

trace, dry, 

and QC

samples

Number 

of rain 

samples

Number of 

snow

samples

Number

of mixed

rain and snow

samples

Roush Lake 2001 52 46 6 38 2 6

2002 52 48 4 33 5 10

2003 53 49 4 33 8 8

3 years 157 143 14 104 15 24

Clifty Falls 2001b 50 44 6 39 0 5

2002 52 45 7 39 3 3

2003 53 51 2 41 4 6

3 years 155 140 15 119 7 14

Bloomington 2001 52 44 8 37 3 4

2002 52 43 9 37 3 3

2003 53 44 9 33 5 6

3 years 157 131 26 107 11 13

Indiana Dunes 2001 52 46 6 38 1 7

2002 52 43 9 31 6 6

2003 53 48 5 32 13 3

3 years 157 137 20 101 20 16

Four stations 3-year total 626 551 75 431 53 67

a

Weekly samples were attempted by installing a sampling train. 

b

Does not include 2 weeks prior to the start of monitoring in January 2001. 

The rain gages at the four monitoring stations operated 

reliably during the 3-year period. Of the 551 wet-deposition samples, the precipitation amount from 96 percent was 

determined with the rain-gage measurement. For the remaining samples, the precipitation amount was determined from 

the sample bottle. The precipitation samplers also operated 

reliably during the 3-year period; precipitation-sampler malfunction made estimated deposition necessary for 6 percent of 

wet-deposition samples.

Total Mercury

A total mercury concentration was determined by laboratory analysis of 517 of the 551 wet-deposition samples from 

the four monitoring stations during the 3-year period; for 34 of 

the 551 wet-deposition samples, the seasonal volume-weighted 

concentration was computed in place of a missing concentration. The volume-weighted total mercury concentration in 

the 517 weekly samples was 11.5 ng/L (table 4). Half the 

weekly concentrations were less than 11.2 ng/L (fig. 11); all 

concentrations ranged from a minimum of 1.54 ng/L in three 

samples at Indiana Dunes in November 2002, January 2003, 

and July 2003 (appendix 1-4) to a maximum of 77 ng/L in one 

sample at Bloomington in September 2002 (appendix 1-3).

The highest concentrations were in 13 samples with total 

mercury greater than 35 ng/L. These 13 concentrations were 

associated with precipitation less than 0.25 in. and deposition 

less than 243 ng/m2 (the mean weekly deposition for Indiana). 

Mercury in Precipitation in Indiana 19
Table 4. Total mercury concentrations in weekly samples at four monitoring 

stations for mercury in precipitation in Indiana, January 2001–December 2003. 

[ng/L, nanogram per liter; 3-year medians may not compute from annual values due to rounding]

Station name Year

Median total 

mercury 

concentration 

(ng/L)

Volumeweighted 

total mercury 

concentration 

(ng/L)

Number 

of samples 

analyzed for 

total mercury

Roush Lake 2001 11.4 11.8 44

2002 10.1 11.4 42

2003 11.0 11.3 47

3 years 11.2 11.4 133

Clifty Falls 2001 11.2 12.5 43

2002 13.4 11.7 44

2003 12.6 13.2 51

3 years 12.3 12.4 138

Bloomington 2001 10.9 10.2 44

2002 9.8 11.0 35

2003 10.2 9.7 42

3 years 10.1 10.3 121

Indiana Dunes 2001 12.7 12.1 43

2002 11.3 12.9 38

2003 14.1 14.7 44

3 years 12.7 13.2 125

Four stations 3 years 11.2 11.5 517

Total mercury concentrations generally were higher in samples 

with small amounts of precipitation rather than samples with 

large amounts of precipitation. All of the 25 samples with 

3 in. or more precipitation had less than 22 ng/L total mercury, 

while 86 percent of the 371 samples with 1 in. or less precipitation had more than 22 ng/L total mercury.

Samples with precipitation as rain had a mean concentration of 14.2 ng/L, which was higher than the mean concentration in snow (9.4 ng/L) or mixed rain and snow (9.7 ng/L). 

Also, mean total mercury deposition from rain (325 ng/m2) 

was seven times that for snow (45.9 ng/m2

) and two times that 

for mixed rain and snow (154 ng/m2). The mean precipitation 

amount for rain samples was 1.1 in., compared with 0.3 in. for 

snow, which explains the higher mercury deposition from rain.

As a reference, 47 percent of the total mercury concentrations determined by the laboratory (241 of 517) were greater 

than the 12 ng/L Indiana water-quality standard8

. The highest 

number of samples with mercury concentrations greater than 

12 ng/L was recorded at Clifty Falls (71 of 138; 51 percent) 

and Indiana Dunes (68 of 125; 54 percent). Nearly all of the 

total mercury concentrations (515 of 517) were greater than 

the Indiana water-quality standards for the Great Lakes system9

.

8

For water in Indiana, the chronic aquatic criterion for mercury is 12 ng/L to 

protect aquatic life from chronic toxic effects (Indiana Administrative Code, 

2005). 

9

For water in Indiana in the Great Lakes system, the water-quality criterion 

for mercury (including methylmercury) is 1.8 ng/L to protect human health 

from adverse noncancer effects that may result from consumption of aquatic 

organisms. Water-quality criterion for mercury (including methylmercury) is 

1.3 ng/L to protect avian and mammalian wildlife populations from adverse 

effects which may result from consumption of aquatic organisms (Indiana 

Administrative Code, 2005). 

20 Mercury in Precipitation in Indiana, January 2001–December 2003
Roush Lake Clifty Falls Bloomington Indiana Dunes

0

20

40

60

80

TOTAL MERCURY CONCENTRATION, 

IN NANOGRAMS PER LITER

50

70

30

10

75th percentile

25th percentile

Median

(50th percentile)

(133) Number of

Value more than

1.5 times the

interquartile range

weekly samples

EXPLANATION (133) (138) (121) (125)

(Box height is the 

interquartile range.

Whisker includes values

within 1.5 times the

interquartile range)

Figure 11. Distribution of total mercury concentrations in weekly samples at four monitoring stations for mercury in precipitation in 

Indiana, January 2001–December 2003. 

The mean weekly total mercury deposition at the four 

monitoring stations during the 3-year period, including weeks 

with no precipitation, was 243 ng/m2 and the mean annual total 

mercury deposition was 12,623 ng/m2 (table 5). Weekly total 

mercury deposition ranged from a minimum of 0.8 ng/m2 at 

Indiana Dunes in November 2002 to a maximum of 

2,456 ng/m2 at Roush Lake in July 2003. In the 551 wetdeposition samples, mean total mercury was 275 ng/m2

 with a 

standard deviation of 327 ng/m2. Box plots of the distributions 

of the weekly deposition illustrate that half the values at the 

four monitoring stations were equal to or less than a median 

of 170 ng/m2; the 90th percentile was skewed to nearly 

1,000 ng/m2 and outliers were as high as 2,456 ng/m2 (fig. 12). A further discussion of the variability of weekly total mercury 

deposition is in the Episodes of High Mercury Deposition section of this report. The highest annual total mercury deposition 

but not the highest annual precipitation every year, 2001–2003, 

was at Clifty Falls (fig. 13 and table 5). Annual total mercury 

deposition at the four monitoring stations varied during the 3-

year period, related closely to annual precipitation (fig. 13). A 

further discussion of the relation of precipitation to deposition 

is in the Precipitation Normals section of this report. 

Methylmercury

Of the 551 wet-deposition samples, 485 samples were 

analyzed for methylmercury. Of those, a methylmercury concentration was reported for 457 samples (94 percent); methylmercury wet deposition was computed for those samples. For 

13 of the 457 samples, a precipitation-sampler malfunction or 

laboratory error required the methylmercury deposition to be 

estimated with the precipitation amount, the seasonal volume-weighted methylmercury concentration, and equation 1.

The median methylmercury concentration in weekly samples 

at the four monitoring stations during the 3-year period was 

0.058 ng/L (table 6). 

At the four monitoring stations during the 3-year period, 

mean weekly methylmercury deposition was 1.70 ng/m2, 

normalized methylmercury deposition was 2.09 ng/m2/in., and 

methylmercury deposition was 0.7 percent of total mercury 

deposition. The highest weekly methylmercury concentration 

(5.77 ng/L) and deposition (136 ng/m2) were in a 0.93-in. rain 

sample at Roush Lake in August 2002 (appendix 1-1). In this 

sample, methylmercury deposition was 17.5 percent of total 

mercury deposition. For the 3-year period, the annual, normalized, and mean weekly methylmercury deposition was highest 

at the Roush Lake station (table 6). 

Mercury in Precipitation in Indiana 21
Table 5. Total mercury deposition in weekly samples at four monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003.

[ng/m2, nanogram per square meter; ng/m2/in., nanogram per square meter per inch; cumulative values in parentheses used for calculations; 

3-year means may not compute from annual values due to rounding]

Station name Year

Annual

precipitation

(in.)

Annual

total mercury

depositiona

(ng/m2)

Normalized

total mercury

depositionb

(ng/m2/in.)

Mean weekly

total mercury

depositionc

(ng/m2)

Mean 

total mercury

deposition

per sampled

Roush Lake 2001 41.1 12,218 297 235 266

2002 31.2 9,326 299 179 194

2003 55.5 15,596 281 294 318

3 years (127.8) (37,140) 291 237 260

Clifty Falls 2001 39.1 12,407 317 248 282

2002 49.9 14,801 297 285 322

2003 52.6 17,473 332 330 349

3 years (141.6) (44,681) 316 288 319

Bloomington 2001 46.1 11,984 260 230 272

2002 45.9 12,568 274 242 292

2003 47.9 11,684 244 220 272

3 years (139.9) (36,236) 259 232 277

Indiana Dunes 2001 35.6 10,926 307 210 232

2002 29.8 9,337 313 180 217

2003 35.7 13,155 368 248 280

3 years (101.1) (33,418) 331 213 244

Four stations Mean 42.5 12,623e 297f 243g 275h

Four stations Minimum 29.8 9,337 244 179 194

Four stations Maximum 55.5 17,473 368 330 349

a

Includes samples with estimated total mercury deposition.

b

Computed as annual or cumulative total mercury deposition divided by annual or cumulative precipitation.

c

Computed as annual or cumulative total mercury deposition divided by number of sampling trains installed (table 3).

d

Computed as annual or cumulative total mercury deposition divided by number of wet-deposition samples (table 3).

e

Mean computed as 3-year cumulative mercury deposition at four stations (151,475 ng/m2) divided by 3 years at four stations.

f

Computed as 3-year cumulative mercury deposition at four stations (151,475 ng/m2) divided by 3-year cumulative precipitation at four 

stations (510 inches).

g

Computed as 3-year cumulative mercury deposition at four stations (151,475 ng/m2) divided by 52 weeks per year for 3 years at four 

stations.

h

Computed as 3-year cumulative mercury deposition at four stations (151,475 ng/m2) divided by 3-year total number of wet-deposition 

samples at four stations (551 samples, table 3). 

22 Mercury in Precipitation in Indiana, January 2001–December 2003
0

500

1,000

1,500

2,000

2,500

Roush Lake Clifty Falls Bloomington Indiana Dunes

TOTAL MERCURY DEPOSITION, 

IN NANOGRAMS PER SQUARE METER PER WEEK

(143) (140) (131) (137)

75th percentile

25th percentile

Median

(50th percentile)

(143) Number of

Value more than

1.5 times the

interquartile range

weekly samples

EXPLANATION

(Box height is the 

interquartile range.

Whisker includes values

within 1.5 times the

interquartile range)

Figure 12. Distribution of total mercury deposition in weekly samples at four monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003. 

Geographic and Temporal Variability of Mercury 

in Precipitation

Geographic variability of mercury in precipitation was 

examined through statistical analysis of total mercury and 

methylmercury concentrations and deposition at the four 

monitoring stations in Indiana. Total mercury concentrations and deposition also were compared with the two nearby 

NADP-MDN monitoring stations in Illinois and Wisconsin, 

and with the entire NADP-MDN. Methylmercury concentrations and deposition in Indiana were compared with data from 

eight NADP-MDN monitoring stations in Wisconsin and Minnesota. Temporal variability of total mercury and methylmercury concentrations and deposition was evaluated for seasonal 

patterns, episodes of high mercury deposition, and the relation 

to precipitation normals.

Geographic Variability

Weekly total mercury deposition and total mercury 

concentrations in weekly samples, 2001–2003, were examined statistically to determine whether there was a difference 

among the four monitoring stations. Weekly total mercury 

deposition was not different (Kruskal-Wallis rank-sum test)10, 

whether estimated deposition values were included (p= 0.151) 

or excluded (p = 0.39). Total mercury concentrations were 

different (Kruskal-Wallis rank-sum test, p= 0.012). Concentrations at Indiana Dunes (median 12.7 ng/L, table 4) were 

higher than those at Bloomington (median 10.1 ng/L, table 4), 

based on a multiple-stage test with Kruskal-Wallis statistic11, 

p = 0.002. Concentrations at Clifty Falls (median 12.3 ng/L, 

table 4) also were higher than those at Bloomington (multiplestage test with Kruskal-Wallis statistic, p = 0.010). 

10The Kruskal-Wallis rank-sum test (Helsel and Hirsch, 1995) is a non-parametric procedure used to evaluate if the distributions of the data from more 

than two stations or years were different. A significance level of 0.05 or less 

was used to accept a statistical difference in the distributions of the data. The 

p-value is the significance attained by the data—the smaller the p-value, the 

more believable the statistical difference.

11The multiple-stage test with Kruskal-Wallis statistic (Helsel and Hirsch, 

1995) is a non-parametric procedure used to evaluate in succession each of the 

two possible comparisons between the four monitoring stations or (later in this 

section of the report, the four seasons.) In this statistical analysis, a significance level of 0.05 or less was used to accept a statistical difference in the 

distributions. The p-value is the significance level attained by the data—the 

smaller the p-value, the more believable the statistical difference. Median values were used to identify which station or season was higher when two were 

compared and statistically different. 

Mercury in Precipitation in Indiana 23
0

5,000

10,000

15,000

0

5,000

10,000

15,000

5,000

10,000

15,000

ROUSH LAKE CLIFTY FALLS

BLOOMINGTON

2001 2002 2003 2001 2002 2003

2001 2002 2003

TOTAL MERCURY DEPOSITION,

IN NANOGRAMS PER SQUARE METER

0

0

10

20

30

40

50

0

10

20

30

40

50

ANNUAL PRECIPITATION, INCHES

0

10

20

30

40

50

ROUSH LAKE (IN20)

CLIFTY FALLS (IN21)

BLOOMINGTON (IN28) 

INDIANA DUNES (IN34)

TOTAL MERCURY DEPOSITION

ANNUAL PRECIPITATION

TOTAL MERCURY DEPOSITION,

IN NANOGRAMS PER SQUARE METER

ANNUAL PRECIPITATION, INCHES

EXPLANATION

TOTAL MERCURY DEPOSITION,

IN NANOGRAMS PER SQUARE METER

ANNUAL PRECIPITATION, INCHES

TOTAL MERCURY DEPOSITION,

IN NANOGRAMS PER SQUARE METER 5,000

10,000

15,000

INDIANA DUNES

2001 2002 2003

0 0

10

20

30

40

50

ANNUAL PRECIPITATION, INCHES

0

5,000

10,000

15,000

2001 2002 2003

TOTAL MERCURY DEPOSITION,

IN NANOGRAMS PER SQUARE METER

Figure 13. Annual total mercury deposition and annual precipitation at four monitoring stations for mercury in precipitation in 

Indiana, January 2001–December 2003. 

24  Mercury in Precipitation in Indiana, January 2001–December 2003
Table 6. Methylmercury concentrations and methylmercury deposition in weekly samples at four monitoring stations in Indiana, 

January 2001–December 2003. 

[ng/L, nanogram per liter; ng/m2, nanogram per square meter; ng/m2/in., nanogram per square meter per inch; cumulative values in parentheses used for 

calculations; 3-year means may not compute from annual values due to rounding]

Station name Year

Median

methylmercury

concentration

(ng/L)

Annual

methylmercury

depositiona

(ng/m2

)

Normalized

methylmercury

depositionb

(ng/m2/in.)

Mean

weekly

methylmercury

depositionc

(ng/m2)

Methylmercury

deposition

percentage

of total 

mercury

depositiond

Number of

samples

with methylmercury

concentration 

reported

Number of 

samples

analyzed

for 

methylmercurye

Roush Lake 2001 0.035 44.5 1.08 0.86 0.4 39 43

2002 .077 260.0 8.33 5.00 2.8 38 42

2003 .079 144.4 2.60 2.72 .9 43 43

3 years .066 (448.9) 3.51 2.86 1.2 120 128

Clifty Falls 2001 .048 35.4 .91 .68 .3 32 43

2002 .046 122.6 2.46 2.36 .8 38 38

2003 .073 90.4 1.72 1.71 .5 46 46

3 years .059 (248.4) 1.75 1.58 .6 116 127

Bloomington 2001 .038 29.7 .64 .57 .2 36 40

2002 .037 54.1 1.18 1.04 .4 36 36

2003 .069 77.3 1.61 1.46 .7 37 37

3 years .051 (161.1) 1.15 1.03 .4 109 113

Indiana Dunes 2001 .040 37.6 1.06 .72 .3 40 43

2002 .057 33.8 1.13 .65 .4 35 37

2003 .080 137.4 3.85 2.59 1.0 37 37

3 years .059 (208.8) 2.07 1.33 .6 112 117

Four stations 3 years .058 (1,067.2) 2.09 1.70 .7 457 485

a

Includes 13 samples with estimated methylmercury deposition.

b

Computed as annual or cumulative methylmercury deposition divided by annual or cumulative precipitation.

c

Computed as annual or cumulative methylmercury deposition divided by number of sampling trains installed.

d

Computed as annual or cumulative methylmercury deposition divided by annual or cumulative total mercury deposition (table 5), expressed 

as percentage.

e

Non-detections of methylmercury are the difference between the samples analyzed and the samples with a concentration reported. 

Mercury in Precipitation in Indiana 25
The annual mercury emissions in the vicinity of Indiana 

Dunes and Clifty Falls were more than 10 times the annual 

mercury emissions in the vicinity of Bloomington, based on 

2001 RAPIDS data for Indiana (table 2). Other factors such as 

the types of mercury emissions, long-range mercury transport 

from sources outside Indiana, and meteorological conditions 

also may help explain the differences in the mercury concentrations. Statistically significant differences in weekly total 

mercury concentrations were not identified among the other 

stations. Weekly methylmercury deposition and methylmercury concentrations were not statistically different among the 

four monitoring stations, 2001–2003 (Kruskal-Wallis ranksum test, p = 0.242 and p = 0.239, respectively).

The four monitoring stations can be ranked by the 3-year 

normalized total mercury deposition and the 3-year volume-weighted total mercury concentration (table 7). Use of 

normalized deposition and volume-weighted concentrations 

tends to remove differences caused by variability in precipitation amounts and sample volumes collected at each station. 

(Calculations of normalized deposition and volume-weighted 

concentration are described in the Data Management and 

Reporting section of this report.) The rankings on this basis 

are similar to the statistical differences in concentration in 

weekly samples, with Indiana Dunes and Clifty Falls the highest and Bloomington the lowest.

for Indiana were compared with the NADP-MDN summaries 

for eastern North America. The highest range of annual precipitation-weighted total mercury concentrations was 14.0 to 

16.7 ng/L (fig. 14). The most numerous concentrations in that 

range were in Florida (15.5–15.4 ng/L), followed by the Lake 

Michigan area (14.7 and 16.7 ng/L). The 14.7 ng/L concentration at Indiana Dunes was the eighth highest of all monitoring 

stations in the NADP-MDN in 2003. Concentrations at the 

monitoring stations in Indiana (with the exception of Bloomington) were in the top 40 percent of all NADP-MDN monitoring stations in 2003.

The highest range of annual total mercury deposition was 

16,000 to 28,500 ng/m2

 in the Gulf Coast states of Louisiana, 

Mississippi, Alabama, Florida, and Georgia (fig. 15). The 

17,200 ng/m2 deposition at Clifty Falls was in the range of the 

Gulf Coast states and was the tenth highest of all NADP-MDN 

monitoring stations in 2003. Annual mercury deposition at the 

four monitoring stations in Indiana was in the top 40 percent 

of annual deposition at all NADP-MDN monitoring stations in 

2003.

Methylmercury deposition and concentrations at the four 

monitoring stations in Indiana, 2001–2003, were compared 

with methylmercury data from the NADP-MDN that were 

available for this time period. Methylmercury data from 

four NADP-MDN monitoring stations in Wisconsin (WI08, 

WI09, WI36, and WI99) and four NADP-MDN monitoring 

stations in Minnesota (MN16, MN18, MN23, and MN27) 

were from monthly composites of weekly samples (Robert 

Brunette, NADP-MDN Laboratory, written commun., 2005). 

The composite samples were analyzed for methylmercury, and 

deposition was computed with the sum of the precipitation 

amount for the samples in each composite. The statewide 

volume-weighted concentration was 0.080 ng/L in Indiana, 

compared with 0.117 ng/L in Wisconsin and 0.089 ng/L 

in Minnesota. The statewide precipitation was higher in 

Indiana than in Minnesota and Wisconsin, which made 

methylmercury deposition in Indiana higher; however, 

methylmercury deposition in Indiana was higher in two 

other ways. Normalized statewide methylmercury deposition 

was estimated at 2.09 ng/m2

/in. for Indiana, compared 

with 1.03 ng/m2/in. for Wisconsin and 0.906 ng/m2/in. for 

Minnesota. Methylmercury was 0.7 percent of total mercury 

deposition in Indiana, compared with 0.3 percent in Wisconsin 

and 0.4 percent in Minnesota. 

Hall and others (2005) reported a mean methylmercury 

concentration of approximately 0.10 ng/L in 424 samples 

collected at 5 sites in the Great Lakes Region, 1997–2003, 

with most samples not exceeding 0.30 ng/L. Methylmercury 

was generally less than 1 percent of total mercury at these 

five sites. Overall, methylmercury deposition in Indiana, 

2001–2003, appeared to be higher than in Wisconsin or 

Minnesota. Methylmercury concentrations in precipitation 

in Indiana were similar to or lower than those in Wisconsin, 

Minnesota, or the five sites in the Great Lakes Region.

Table 7. Normalized total mercury deposition and 

volume-weighted total mercury concentration at four 

monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003. 

[ng/m2/in., nanogram per square meter per inch of precipitation; ng/L, 

nanogram per liter]

Statewide 

rank 

Station

name

Normalized 

total mercury 

deposition 

(ng/m2

/in.)

Volumeweighted 

total mercury

concentration 

(ng/L)

1 Indiana Dunes 331 13.2

2 Clifty Falls 316 12.4

3 Roush Lake 291 11.4

4 Bloomington 259 10.3

The annual precipitation-weighted total mercury concentrations12 and annual total mercury deposition during 2003 

were summarized for the NADP-MDN (National Atmospheric 

Deposition Program, 2004) and for illustration, the 2003 data 

12Precipitation-weighted concentration is similar to the volume-weighted 

concentration defined in the Data Management and Reporting section of this 

report. The weekly precipitation-weighted concentration is the product of the 

weekly total mercury concentration and the ratio of the weekly precipitation 

to the annual precipitation. The annual precipitation-weighted concentration is 

the sum of the weekly precipitation weighted concentrations.

26  Mercury in Precipitation in Indiana, January 2001–December 2003
Range of total mercury concentrations

in precipitation, in nanograms per liter

EXPLANATION

National Atmospheric Deposition ProgramMercury Deposition Network monitoring station and annual precipitation-weighted concentration, in nanograms per liter

14.7

Less than 44 to 5.996 to 7.998 to 9.9910 to 11.9912 to 13.9914 to 15.9916 to 17.99Greater than 18

Figure 14. National Atmospheric Deposition Program Mercury Deposition Network monitoring stations with annual precipitation-weighted total mercury concentrations in 2003 and ranges of total mercury concentrations for eastern North America (modified from National Atmospheric Deposition Program, 2004). 

Mercury in Precipitation in Indiana 27
Range of annual total mercury deposition, 

in nanograms per square meter

EXPLANATION

National Atmospheric Deposition Program Mercury Deposition Network monitoring station and annual total mercury deposition in 2003, in nanograms per square meter

Less than 4,0004,000 to 5,9996,000 to 7,9998,000 to 9,99910,000 to 11,99912,000 to 13,99914,000 to 15,99916,000 to 17,999Greater than 18,000

4,700

7,200 6,000 6,400

7,200

7,200

9,400 8,000

8,800 6,000

11,600 7,600 10,500

11,600

12,600

12,100

10,800 10,600

13,200

13,200

11,200

14,000

12,700

14,900

19,300

28,500

17,800

26,800

19,400

17,700 13,000

26,800

16,100

24,600

18,000

11,700

17,200 11,600

9,400

15,300

13,200 9,300

8,500 8,400

5,800 7,100

4,900

7,700

5,900

7,800

7,700

5,900

14,600

13,500

12,100

9,500 7,300

4,000

5,100

2,200

13,200

4,300

6,000

6,900

3,600

Figure 15. National Atmospheric Deposition Program Mercury Deposition Network monitoring stations with annual total mercury deposition in 2003 and ranges of total mercury deposition for eastern North America (modified from National Atmospheric Deposition Program, 2004). 

28  Mercury in Precipitation in Indiana, January 2001–December 2003
Seasonal Patterns 

Total mercury deposition and concentrations exhibited 

seasonal patterns and a statistical difference when grouped 

by season (Kruskal-Wallis rank-sum test, p < 0.001 and 

p < 0.001, respectively). Winter mercury deposition was 

significantly lower than that for spring, summer, and fall 

(multiple-stage test with Kruskal-Wallis statistic, p < 0.001, 

p < 0.001, and p = 0.003). Fall mercury deposition was significantly lower than that for spring and summer (p < 0.001 and 

p = 0.006, respectively). Spring and summer mercury deposition were not significantly different (p = 0.117). A bar graph 

of seasonal total mercury deposition (fig. 16) illustrates the 

seasonal patterns at the four monitoring stations, 2001–2003, 

and the close relation to seasonal precipitation. 

Total mercury concentrations in spring and summer were 

significantly higher than concentrations in fall and winter 

(p < 0.001). Concentrations were not significantly different 

between winter and fall (p = 0.166) or between spring and 

summer (p = 0.808). Median values provide a scale of the 

differences in total mercury deposition and total mercury 

concentrations grouped by season (table 8). Seasonal patterns 

for total mercury deposition and concentrations that were 

similar to those in Indiana have been reported in other states, 

as summarized for 10 studies in Downs and others (1998), for 

the upper Midwest by Glass and Sorensen (1999), for Pennsylvania by Lynch and others (2005), and for Maryland by Mason 

and others (2000).

Methylmercury deposition and concentrations exhibited 

different seasonal patterns than did those for total mercury, 

and showed a statistical difference when grouped by season 

(Kruskal-Wallis rank-sum test, p = 0.025 and p = 0.001, 

respectively). Methylmercury deposition was statistically 

higher in spring than in winter, summer, and fall (multiplestage test with Kruskal-Wallis statistic, p = 0. 001, p = 0.002, 

and p = 0.006, respectively). Methylmercury concentrations 

in winter were statistically higher than in summer and fall 

(p = 0.028 and p = 0.022), and methylmercury concentrations 

in spring were higher than in summer and fall (p = 0.043 and 

p = 0.034). Median values provide a scale of the differences in 

methylmercury deposition and methylmercury concentrations 

grouped by season (table 8). 

Episodes of High Mercury Deposition 

Eleven weekly samples recorded episodes of high mercury deposition (table 9). For purposes of this discussion: precipitation events are separated by a break of 8 hours or more in 

precipitation accumulation; an episode is one or more precipitation events collected in a weekly sample; and high mercury 

deposition is more than 1,262 ng/m2

 (which is 10 percent of 

12,623 ng/m2

, the mean annual mercury deposition at the four 

monitoring stations, 2001–2003). Mercury deposition in these 

11 samples was 5 to 10 times the mean weekly deposition for 

Indiana (243 ng/m2). Most of the samples contained approximately 3 in. or more of rain from two or more precipitation 

events. Seven of the 11 samples were collected in spring and 

summer 2003. 

Weekly samples with episodes of high mercury deposition were recorded at all four monitoring stations. The greatest 

number (5 samples) was at Clifty Falls. The sample with the 

highest mercury deposition (2,456 ng/m2 at Roush Lake, July 

2003) was 15.7 percent of the annual mercury deposition that 

year. At Clifty Falls in May, July, August, and September 

2003, three samples with episodes of high mercury deposition 

contributed 31 percent of the annual deposition. Six samples 

showed high mercury deposition at more than one station in 

the same week—Indiana Dunes and Clifty Falls, May 7–14, 

2002; Roush Lake and Clifty Falls, May 6–13, 2003; and 

Bloomington and Clifty Falls, July 8–15, 2003. Among these 

three pairs of samples, concentrations differed by less than 

10 ng/L, indicating precipitation amount probably was more 

important than concentration in episodes of high mercury 

deposition.

Mercury concentrations in the 11 samples with high mercury deposition ranged from 10.5 to 22.4 ng/L, but were not 

the highest mercury concentrations recorded in Indiana, 

2001–2003. The sample with the highest mercury concentration that had the highest mercury deposition was at Clifty 

Falls, May 13–21, 2002. That sample contained 0.79 in. rain 

from one precipitation event, a 51.7 ng/L mercury concentration, and 1,036.8 ng/m2 mercury deposition, which was 

7 percent of the annual deposition (appendix 1-2). Other investigators have reported high mercury concentrations in highintensity or in short-duration precipitation events (for example, 

Downs and others, 1998; Mason and others, 1997).

Weekly samples with episodes of high mercury deposition were not unique to Indiana. In a study of patterns of mercury deposition at NADP-MDN stations in northeastern North 

America, 1996–2002, Vanarsdale and others (2005) reported 

episodes13 of high mercury deposition occurred networkwide, with some stations recording more episodes than others. 

In that study, it was shown that the greater the number of 

episodes of high mercury deposition14 at a station, the greater 

their contribution to annual deposition. For Indiana, this relation could mean that although weekly mercury deposition was 

not statistically different among the four monitoring stations, 

2001–2003, episodes of high mercury deposition may help to 

explain the differences in annual mercury deposition among 

the stations. For example, Clifty Falls had the highest annual 

mercury deposition every year, 2001–2003, and the most episodes of high mercury deposition.

13Episodes were called “periods” by Vanarsdale and others (2005).

14High mercury deposition was called “enhanced mercury deposition” by 

Vanarsdale and others (2005).

Mercury in Precipitation in Indiana 29
0

1000

2000

3000

4000

5000

6000

7000

8000

0

5

10

15

20

25

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

SEASONAL PRECIPITATION, 

IN INCHES

SEASONAL TOTAL MERCURY DEPOSITION,

IN NANOGRAMS PER SQUARE METER

WINTER

SPRING

SUMMER

FALL

EXPLANATION

ROUSH LAKE

WINTER (January, February, March)

SPRING (April, May, June)

SUMMER (July, August, September)

FALL (October, November, December)

CLIFTY FALLS 

BLOOMINGTON

INDIANA DUNES

SEASONS

2001

WINTER

SPRING

SUMMER

FALL

WINTER

SPRING

SUMMER

FALL

2002 2003

WINTER

SPRING

SUMMER

FALL

WINTER

SPRING

SUMMER

FALL

WINTER

SPRING

SUMMER

FALL

2001 2002 2003

Figure 16. Seasonal total mercury deposition and seasonal precipitation at four monitoring stations for 

mercury in precipitation in Indiana, January 2001–December 2003. 

30 Mercury in Precipitation in Indiana, January 2001–December 2003
Table 8. Median total mercury and methylmercury deposition and concentrations, in weekly samples grouped by season, 

at four monitoring stations for mercury in precipitation in Indiana, January 2001–December 2003. 

[ng/m2, nanogram per square meter; ng/L, nanogram per liter]

Season

Median

total mercury

deposition

(ng/m2

)

Median

total mercury 

concentration

(ng/L)

Median

methylmercury 

deposition

(ng/m2

)

Median

methylmercury 

concentration

(ng/L)

Winter (January, February, March) 48.4 9.16 0.500 0.071

Spring (April, May, June) 273 15.1 1.06 .069

Summer (July, August, September) 184 14.5 .510 .047

Fall (October, November, December) 102 7.71 .660 .052

Table 9. Weekly samples with episodes of high mercury deposition at four monitoring stations for mercury in precipitation in 

Indiana, January 2001–December 2003. 

[ng/m2, nanogram per square meter; ng/L, nanogram per liter]

Station name Sample time period

Total mercury

deposition 

(ng/m2

)

Percentage of

annual mercury

depositiona

Total mercury

concentration

(ng/L)

Weekly

precipitation

(inches)

Number of

precipitation

eventsb

Roush Lake July 1–8, 2003 2,456.1 15.7 11.0 8.78 4

Clifty Falls July 8–15, 2003 2,042.9 11.7 22.4 3.59 3

Clifty Falls August 26–September 2, 2003 1,765.7 10.1 10.6 6.53 5

Roush Lake May 6–13, 2003 1,753.9 11.2 12.5 5.53 5

Clifty Falls December 11–18, 2001 1,702.7 13.7 22.3 3.00 3

Clifty Falls May 6–13, 2003 1,604.6 9.20 21.3 2.96 3

Indiana Dunes October 9–16, 2001 1,491.7 13.7 11.1 5.30 4

Bloomington July 8–15, 2003 1,464.6 12.5 12.5 4.61 2

Indiana Dunes May 7–14, 2002 1,458.2 15.6 13.4 4.27 2

Indiana Dunes July 15–22, 2003 1,293.1 9.80 17.3 2.94 2

Clifty Falls May 7–14, 2002 1,266.3 8.60 10.5 4.75 3

a

Percentage of annual mercury deposition is for the station listed.

b

In this report, precipitation events are separated by a break of 8 hours or more in precipitation accumulation. 

Mercury in Precipitation in Indiana 31
Precipitation Normals

Monthly precipitation amounts measured at the four 

monitoring stations, January 2001–December 2003, were compared with monthly precipitation normals, 1971–2000, for four 

of the nine climate divisions in Indiana where the monitoring 

stations were located (Purdue Applied Meteorology Group, 

2005). The monthly precipitation amounts at the monitoring 

stations and the precipitation normals were grouped by season 

and graphed (fig. 17). The graphs generally illustrate that 

winter precipitation, 2001–2003 was below normal; summer 

precipitation during 2002 was below normal; spring-summer 

precipitation during 2003 was above normal. These comparisons are consistent with annual precipitation amounts at the 

four monitoring stations that generally were higher in 2003 

than 2001 and 2002 (table 10). 

Annual total mercury deposition combined from the 

four monitoring stations was 26 percent higher in 2003 than 

in 2002 and 22 percent higher in 2003 than in 2001. The 

differences were as much as 67 percent (Roush Lake, 2003 

and 2002) and 41 percent (Indiana Dunes, 2003 and 2002; 

Clifty Falls, 2003 and 2001); the yearly difference at Bloomington was less than 7 percent. Annual differences in the 

mercury deposition may be explained by departures from 

precipitation normals, which reinforce the benefit of a longterm record for mercury monitoring. Data from two monitoring stations provide examples of annual precipitation that was 

higher than normal. These data corresponded with the highest 

annual mercury deposition. First, Roush Lake had 55.5 in. 

of annual precipitation in 2003—49.2 percent higher than 

the normal for that climate division. Annual total mercury 

deposition at Roush Lake was 67 percent higher in 2003 than 

in 2002 and 28 percent higher in 2003 than in 2001. Mean 

weekly total mercury deposition at Roush Lake was highest in 

2003. Second, Clifty Falls had 52.6 in. of annual precipitation 

in 2003—117 percent higher than the normal for that climate 

division. Annual total mercury deposition at Clifty Falls was 

18 percent higher in 2003 than in 2002 and 41 percent higher 

in 2003 than in 2001. Mean weekly total mercury deposition at 

Clifty Falls was highest in 2003.

Table 10. Precipitation normals, 1971–2000, and annual precipitation at four monitoring stations for mercury in precipitation in Indiana, 

January 2001–December 2003.

[NE, northeast; SE, southeast; SC, south central; NW, northwest]

Station name Climate 

division

Precipitation

normal,

1971–2000

(in.)a

Annual

precipitation

in 2001

(in.)

Ratio of

annual 

precipitation 

to

precipitation

normal

(percent)

Annual

precipitation

in 2002

(in.)

Ratio of

annual 

precipitation 

to

precipitation

normal

(percent)

Annual

precipitation

in 2003

(in.)

Ratio of

annual 

precipitation 

to

precipitation

normal

(percent)

Roush Lake NE 37.21 41.1 110.5 31.2 83.8 55.5 149.2

Clifty Falls SE 44.97 40.7 90.5 49.9 111.0 52.6 117.0

Bloomington SC 46.79 46.1 98.5 45.9 98.1 47.9 102.4

Indiana Dunes NW 38.56 35.6 92.3 29.8 77.3 35.7 92.6

a

Purdue Applied Meteorology Group, 2005. 

32 Mercury in Precipitation in Indiana, January 2001–December 2003
EXPLANATION WINTER (January, February, March)

SPRING (April, May, June)

0

5

10

15

20

25

SEASONAL

 PRECIPITATION, IN INCHES

WINTER SPRING SUMMER FALL

200120022003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

Roush Lake

0

5

10

15

20

25

SEASONAL

 PRECIPITATION, IN INCHES

WINTER SPRING SUMMER FALL

200120022003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

Clifty Falls

0

5

10

15

20

25

SEASONAL

 PRECIPITATION, IN INCHES

WINTER SPRING SUMMER FALL

200120022003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

Bloomington

0

5

10

15

20

25

SEASONAL

 PRECIPITATION, IN INCHES

WINTER SPRING SUMMER FALL

20012002

2003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

200120022003

NORMAL

Indiana Dunes

SUMMER (July, August, September)

FALL (October, November, December)

Figure 17. Seasonal precipitation at four monitoring stations for mercury in precipitation in 

Indiana, January 2001–December 2003, with precipitation normals, 1971–2000. 

Mercury in Precipitation in Indiana 33
Summary and Conclusions

Atmospheric mercury is transported to aquatic ecosystems by precipitation. Fish living in aquatic ecosystems 

with low concentrations of inorganic mercury are known to 

accumulate levels of methylmercury in their tissue that pose 

a health risk to humans and wildlife that eat these fish. Prior 

to 2001, few data were available that provided information 

about the atmospheric deposition of mercury in Indiana. 

The U.S. Geological Survey, in cooperation with the Indiana Department of Environmental Management, operated a 

monitoring program for mercury in precipitation in Indiana, 

2001–2003.

The monitoring program in Indiana was part of the 

National Atmospheric Deposition Program-Mercury Deposition Network (NADP-MDN), which had 79 monitoring stations throughout North America in 2003. The monitoring stations in Indiana were located at Roush Lake near Huntington, 

Clifty Falls near Madison, Bloomington, and Indiana Dunes 

near Porter. Precipitation was measured and weekly samples 

were analyzed for total mercury and methylmercury by methods achieving detection limits as small as 0.05 ng/L for total 

mercury and 0.002 ng/L for methylmercury. Total mercury and 

methylmercury deposition was computed with the mercury 

concentrations and the precipitation amounts. 

The volume-weighted total mercury concentration measured in 517 weekly samples collected in Indiana, 2001–2003, 

was 11.5 ng/L (nanograms per liter). As a reference, total 

mercury concentrations exceeded the 12 ng/L Indiana waterquality standard in 47 percent of the samples and exceeded 

the 1.3 ng/L Indiana water-quality standard for the Great 

Lakes System in 99 percent of the samples. Weekly total 

mercury concentrations at Indiana Dunes and Clifty Falls were 

statistically higher than at Bloomington, as were the values 

of the 3-year volume-weighted total mercury concentration 

and 3-year normalized total mercury deposition. The annual 

mercury emissions in the vicinity of Indiana Dunes and Clifty 

Falls in 2001 were more than 10 times the annual mercury 

emissions in the vicinity of Bloomington (although mercuryemission types, mercury from sources outside Indiana, and 

meteorological conditions also may help explain the differences).

The 3-year normalized total mercury deposition computed for 551 weekly samples in Indiana was 297 nanograms 

per square meter per inch of precipitation. When the four 

monitoring stations are ranked by the 3-year normalized total 

mercury deposition and the 3-year volume-weighted total 

mercury concentration, Indiana Dunes and Clifty Falls ranked 

highest and Bloomington ranked lowest of the four monitoring stations. Among all the NADP-MDN stations in 2003, the 

annual mercury deposition at Clifty Falls was in the highest 

range and the precipitation-weighted total mercury concentration at Indiana Dunes in 2003 was in the highest range.

Methylmercury, the form of mercury that accumulates 

and concentrates in aquatic food chains, was detected in 

94 percent of samples analyzed. The mean methylmercury 

deposition was 0.7 percent of total mercury deposition in 

all samples. Methylmercury deposition in Indiana for 2001 

through 2003 was higher than methylmercury deposition 

reported at eight NADP-MDN stations in Wisconsin and Minnesota for the same time period.

Eleven of the 551 weekly wet-deposition samples in Indiana recorded episodes of high mercury deposition in which 

at least 10 percent of the statewide mean annual mercury 

deposition was contributed by a single sample. Most recorded 

episodes were in spring and summer 2003. Weekly samples 

with episodes of high mercury deposition are not unique to 

Indiana. Although weekly mercury deposition was not statistically different among the four monitoring stations, 2001–2003, 

episodes of high mercury deposition may contribute to the differences in annual mercury deposition among the stations. For 

example, Clifty Falls had the highest annual mercury deposition and the most episodes of high mercury deposition.

Differences in annual mercury deposition may be 

explained by departures from precipitation normals, which 

reinforce the benefit of a long-term record. Data from Roush 

Lake and Clifty Falls in 2003 provide examples of annual precipitation that was higher than normal and that corresponded 

with the highest annual mercury deposition at these stations. 

The monitoring program for mercury in precipitation in 

Indiana, 2001–2003, revealed information about total mercury 

and methylmercury concentrations, mercury wet deposition, 

and how they differed geographically and temporally. The data 

in this report constitute a baseline of information for comparison with future data in Indiana and with NADP-MDN data 

from other states. A long-term, consistent monitoring program 

for mercury in precipitation in Indiana has the capability of 

detecting changes that may result from emission controls 

required by Federal and State rules after 2003.

Acknowledgments

Robert (“Bob”) Brunette, director of the Mercury Deposition Network Laboratory at Frontier Geosciences, Inc., provided extensive oversight and contributed to the reporting and 

quality control of the mercury analytical data presented in the 

appendixes. Mark Nilles, Atmospheric Deposition Program 

Manager for the U.S. Geological Survey, was instrumental 

in the development and operation of the monitoring network 

in Indiana. The author acknowledges the contributions of the 

Indiana Department of Environmental Management Mercury 

Work Group for the objectives of the monitoring program and 

the locations of the monitoring stations; Paula Smith (former Assistant Commissioner for Planning and Assessment) 

chaired the Work Group. Cooperation and assistance from the 

34  Mercury in Precipitation in Indiana, January 2001–December 2003
managers and personnel at the sites of the monitoring stations has been essential: the National Park Service at Indiana 

Dunes National Lakeshore, the Indiana Department of Natural 

Resources at Roush Lake and Clifty Falls State Park, and the 

Monroe County Airport Authority at Bloomington. Kathleen 

Fowler of the U.S. Geological Survey operated the Bloomington monitoring station and verified the data in this report. Bret 

Robinson of the U.S. Geological Survey helped establish the 

monitoring stations in Indiana. Clyde Sweet with the National 

Atmospheric Deposition Program coordinated equipment and 

logistics for the monitoring stations. The author extends his 

gratitude to all the individuals involved with the monitoring 

program for mercury in precipitation in Indiana.

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Office of Air Quality Planning and Standards and Office of 

Research and Development, EPA452/R-97-003, 95 p.

U.S. Environmental Protection Agency, 1997b, Method 

1630—Methylmercury in water by distillation, aqueous ethylation, purge and trap, and cold vapor atomic fluorescence 

spectrometry (CVFAS), Draft: Office of Water, Region 1, 

01A00007846.

U.S. Environmental Protection Agency, 1999a, Mercury 

update—Impact on fish advisories: Office of Water, 

Fact Sheet EPA-823-F-99-016.

U.S. Environmental Protection Agency, 1999b, Method 1631, 

Revision B—Mercury in water by oxidation, purge and trap, 

and cold vapor atomic fluorescence spectrometry: Office of 

Water, EPA 821-R-99-012 and subsequent revisions.

U.S. Environmental Protection Agency, 2004, E-GRID 

Emissions and generation resource integrated database: 

accessed January 2004, at 

http://www.epa.gov/airmarkets/egrid/index.html

36  Mercury in Precipitation in Indiana, January 2001–December 2003
Vanarsdale, Alan, Weiss, Jeri, Keeler, Gerald, Miller, Eric, 

Boulet, Gille, Brulotte, Reynald, and Poissant, Laurier, 

2005, Patterns of mercury deposition and concentration in 

northeastern North America (1996–2002): Ecotoxicology, 

v. 14, p. 37–52.

Vermette, Stephen, Lindberg, Steven, and Bloom, Nicolas, 

1995, Field tests for a regional mercury deposition network—Sampling design and preliminary test results: Atmospheric Environment, v. 29, p. 1,247–1,251. 

References Cited 37
This page is intentionally blank.
Appendixes 1-1 through 2-1 
Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003. 

[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

01/02/2001 2.54 0.10 (69.2) W Snow 2 C [8.8] 22.37 Low vol Low vol -- Precipitation from

NTN record; estimateddeposition.

01/09/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

01/16/2001 1.27 .05 5.2 W Mixed 1 B 33.27 42.25 Low vol Low vol -- No comment.01/23/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

01/30/2001 16.0 .63 192.7 W Mixed 3 B 12.96 207.4 0.106 1.694 0.8 No comment.02/6/2001 5.08 .20 57.8 W Mixed 4 B 4.38 22.29 .181 .920 4.1 No comment.02/13/2001 27.81 1.09 329.7 W Rain 1 B 7.87 219.08 .007 .198 .1 No comment.02/20/2001 14.16 .56 174.8 W Rain 1 B 8.08 114.53 .080 1.128 1.0 No comment.02/27/2001 25.4 1.0 304.5 W Rain 2 B 10.25 260.47 .035 .900 .3 No comment.03/6/2001 .13 .01 (.8) T Trace snow 0 B -- 0 Low vol Low vol -- No comment.

03/13/2001 4.57 .18 58.6 W Mixed 3 B 6.85 31.32 .076 .350 1.1 No comment.03/20/2001 10.92 .43 131.5 W Mixed 1 B 4.87 53.27 <.014 0 -- MHg not detected.03/27/2001 .51 .02 (.8) W Snow 1 C [8.8] 4.49 Low vol Low vol -- Low volume sample; 

estimated deposition.

04/3/2001 4.06 .16 49.3 W Rain 1 B 3.68 14.95 .065 .264 1.8 No comment.04/11/2001 6.16 .24 85.0 W Rain 3 B 44.77 275.8 .074 .459 .2 No comment.04/17/2001 42.57 1.68 510.0 W Mixed 1 B 19.59 834.14 .012 .528 .1 Use bottle catch

42.57 mm to computedeposition.

40 Mercury in Precipitation in Indiana, January 2001–December 2003 
04/24/2001 13.72 0.54 202.7 W Rain 4 B 33.25 456.07 0.115 1.583 .3 No comment.

05/1/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

05/8/2001 4.89 .19 57.3 W Rain 3 B 25.10 122.72 .088 .430 .4 No comment.05/15/2001 9.91 .39 126.1 W Rain 1 B 11.50 113.99 .432 4.282 3.8 No comment.05/22/2001 44.45 1.75 402.5 W Rain 4 B 8.81 391.60 .072 3.225 .8 No comment.05/29/2001 26.67 1.05 361.8 W Rain 5 B 9.93 265.01 .017 .451 .2 No comment.06/05/2001 23.88 .94 316.4 W Rain 3 B 15.76 376.47 .034 .821 .2 No comment.06/12/2001 60.71 2.39 756.6 W Rain 3 B 13.97 848.30 .003 .175 0 No comment.06/19/2001 21.34 .84 241.4 W Rain 1 B 9.69 206.78 .017 .357 .2 No comment.06/26/2001 20.32 .80 266.0 W Rain 3 B 16.50 335.34 .019 .384 .1 No comment.07/3/2001 3.81 .15 48.5 W Rain 3 B 27.41 104.44 .035 .135 .1 No comment.07/10/2001 62.99 2.48 757.5 W Rain 2 B 14.98 944.18 .070 4.409 .5 No comment.07/17/2001 5.84 .23 64.2 W Rain 1 B 15.24 89.06 <.016 0 -- MHg not detected.07/24/2001 10.67 .42 136.6 W Rain 2 B 13.15 140.38 .017 .177 .1 No comment.07/31/2001 34.8 1.37 410.3 W Rain 2 B 33.28 1,158.07 .026 .889 .1 No comment.08/7/2001 0 0 (2.8) D Dry 0 B -- 0 -- 0 -- No comment.08/14/2001 10.92 .43 132.8 W Rain 1 B 11.76 128.51 .008 .083 .1 No comment.08/21/2001 24.26 .96 276.6 W Rain 2 B 11.23 272.57 .080 1.945 .7 No comment.08/28/2001 85.09 3.35 1,071.9 W Rain 2 B 11.33 964.06 .057 4.853 .5 No comment.09/04/2001 2.79 .11 32.6 W Rain 1 B 39.16 109.42 <.021 0 -- MHg not detected

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-1  41
09/11/2001 52.75 2.08 632.0 W Rain 3 B 13.89 733.00 0.014 0.717 0.1 Use bottle catch

52.75 mm to compute 

deposition.

09/18/2001 9.4 .37 108.6 W Rain 2 B 22.72 213.56 .011 .1 0 No comment.09/25/2001 36.07 1.42 443.4 W Rain 2 B 6.34 228.95 .016 .579 .3 No comment.10/02/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank 

sample; no Hg detected.

10/09/2001 34.54 1.36 424.2 W Rain 2 B 4.42 152.96 .028 .953 .6 No comment.10/16/2001 112.52 4.43 1,349.7 W Rain 5 B 4.82 542.80 .026 2.981 .5 No comment.10/23/2001 32.51 1.28 390.1 W Rain 4 B 9.84 320.04 .027 .892 .3 No comment.10/30/2001 22.1 .87 210.9 W Rain 1 B 8.88 196.40 .029 .631 .3 No comment.11/06/2001 8.89 .35 107.1 W Rain 1 B 20.19 179.56 .036 .319 .2 No comment.11/13/2001 2.29 .09 20.1 W Rain 3 B 2.49 5.69 <.014 0 -- MHg not detected.11/20/2001 1.78 .07 10.1 W Rain 3 B 22.54 40.08 .180 .321 .8 No comment.11/27/2001 10.16 .40 116.6 W Rain 2 B 6.63 67.39 .014 .144 .2 No comment.12/04/2001 33.02 1.3 405.1 W Rain 2 B 5.93 196.10 .042 1.394 .7 No comment.12/11/2001 .63 .02 9.0 W Rain 2 B 14.02 8.90 .226 .142 1.6 No comment.12/18/2001 54.1 2.13 637.5 W Rain 3 B 3.57 193.63 .068 3.678 1.9 No comment.12/25/2001 3.94 .16 31.1 W Rain 1 B 2.34 9.23 .253 .996 1.8 No comment.01/01/2002 .51 .02 0 W Snow 1 C [6.8] 3.47 Low vol Low vol -- Low volume sample; 

estimated deposition.

01/08/2002 3.81 .15 23.8 W Snow 1 B 1.61 6.14 <.007 0 -- MHg not detected.

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

42 Mercury in Precipitation in Indiana, January 2001–December 2003 
01/15/2002 2.79 0.11 23.2 W Mixed 2 B 8.85 24.73 0.583 1.628 6.6 No comment.

01/22/2002 1.27 .05 0 W Snow 1 C [6.8] 8.64 Low vol Low vol -- Low volume sample; 

estimated deposition.

01/29/2002 2.03 .08 12.1 W Mixed 1 B 15.15 30.79 <.007 0 -- MHg not detected02/05/2002 80.01 3.15 1,000.4 W Rain 1 B 6.24 499.26 .022 1.762 .4 No comment.02/12/2002 4.32 .17 48.6 W Rain 1 B 6.08 26.27 <.089 0 -- MHg not detected.02/19/2002 5.59 .22 69.2 W Mixed 2 B 8.55 47.77 Low vol Low vol -- No comment.02/26/2002 35.05 1.38 418.4 W Mixed 3 B 7.06 247.46 .033 1.158 .5 No comment.03/05/2002 17.02 .67 161.1 W Rain 2 B 2.84 48.33 .017 .290 .6 No comment.03/12/2002 18.29 .72 205.8 W Mixed 2 B 7.26 132.86 .038 .696 .5 No comment.03/19/2002 3.3 .13 41.8 W Rain 1 B 14.71 48.57 .082 .271 .6 No comment.03/26/2002 20.07 .79 85.9 W Mixed 2 B 12.34 247.69 .113 2.270 .9 No comment.04/02/2002 27.18 1.07 293.5 W Rain 3 B 8.92 242.53 .035 .959 .4 No comment.04/09/2002 29.72 1.17 (393.8) W Rain 3 C [15.5] 461.00 [.36] 10.707 2.3 Estimated THg and

MHg deposition.

04/16/2002 10.16 .40 117.9 W Rain 1 B 9.50 96.54 .003 .026 0 No comment.04/23/2002 12.02 .47 144.0 W Rain 1 B 23.20 278.93 .133 1.604 .6 Use bottle catch 

12.02 mm to compute deposition.

04/30/2002 29.97 1.18 363.6 W Rain 2 C 9.64 289.10 .364 10.907 3.8 Sampler lid stuck part

way for one rain; norain missed; use forsummary.

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-1  43
05/07/2002 7.37 0.29 98.5 W Rain 2 C 18.50 136.32 0.164 1.208 0.9 Loose part on sampler

repaired; no rainmissed; use forsummary.

5/14/20020 47.24 1.86 (632.2) W Rain 3 C [15.5] 732.76 [.36] 17.019 2.3 Estimated THg and

MHg deposition.

05/21/2002 9.91 .39 122.5 W Rain 2 B 10.49 103.99 Low vol Low vol -- No comment.05/28/2002 45.97 1.81 534.4 W Rain 2 B 20.31 933.82 1.132 52.083 5.6 No comment.06/04/2002 3.30 .13 45.9 W Rain 3 B 18.46 60.96 <.002 0 -- MHg not detected.06/11/2002 29.21 1.15 344.0 W Rain 1 B 18.2 531.76 .05 1.466 .3 No comment.06/18/2002 19.05 .75 242.1 W Rain 4 B 16.45 313.52 .122 2.322 .7 No comment.06/25/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

07/02/2002 .51 .02 7.7 W Rain 1 B 5.91 3.00 .122 .062 2.1 No comment.07/09/2002 5.84 .23 61.0 W Rain 2 B 17.53 102.45 .089 .521 .5 No comment.07/16/2002 17.27 .68 205.0 W Rain 1 B 14.75 254.88 .167 2.885 1.1 No comment.07/23/2002 9.65 .38 108.5 W Rain 1 B 12.36 119.32 .046 .448 .4 No comment.07/30/2002 37.59 1.48 442.7 W Rain 3 B 5.99 225.32 .038 1.427 .6 No comment.08/06/2002 1.52 .06 10.2 W Rain 1 B 71.05 108.28 .146 .222 .2 No comment.08/13/2002 2.29 .09 (23.2) W Rain 1 C [15.1] 34.6 .425 .974 2.8 Laboratory error;

estimated THgdeposition.

08/20/2002 39.37 1.55 467.1 W Rain 3 B 14.61 575.35 .072 2.843 .5 No comment.08/27/2002 23.62 .93 299.2 W Rain 1 B 33.04 780.56 5.767 136.328 17.5 No comment.

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

44  Mercury in Precipitation in Indiana, January 2001–December 2003 
09/03/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

09/10/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

09/17/2002 1.52 0.06 21.3 W Rain 1 B 13.56 20.66 0.091 0.139 0.7 No comment.09/24/2002 33.02 1.3 397.6 W Rain 1 B 11.94 394.55 .017 .569 .1 No comment.10/01/2002 20.32 .8 238.6 W Rain 1 A 17.68 359.25 .017 .341 .1 No comment.10/08/2002 14.73 .58 170.6 W Rain 2 A 8.45 124.46 .024 .355 .3 No comment.10/15/2002 1.27 .05 (2.4) W Rain 1 B [7.5] 9.40 Low vol Low vol -- Low volume sample;

estimated deposition.

10/22/2002 9.40 .37 103.2 W Rain 1 B 11.54 108.48 .119 1.119 1.0 No comment.10/29/2002 17.02 .67 217.8 W Mixed 1 A 2.89 49.21 .051 .870 1.8 No comment.11/05/2002 10.41 .41 137.0 W Rain 2 A 4.87 50.78 .05 .522 1.0 No comment.11/12/2002 41.15 1.62 476.5 W Rain 2 A 5.06 208.45 .028 1.171 .6 No comment.11/19/2002 9.91 .39 79.4 W Mixed 2 B 5.78 57.27 .092 .914 1.6 No comment.11/26/2002 6.35 .25 70.8 W Mixed 2 A 5.12 32.51 .113 .716 2.2 No comment.12/3/2002 3.30 .13 19.4 W Snow 3 A 6.08 20.08 .030 .099 .5 No comment.12/10/2002 0 0 0 D QC 0 B <0.05 0 -- 0 -- Field bottle blank

sample; no Hg detected.

12/17/2002 .51 .02 3.3 W Snow 1 B 15.41 7.83 Low vol Low vol -- No comment.12/24/2002 19.56 .77 237.2 W Mixed 3 A 6.43 125.77 .055 1.072 .9 No comment.12/31/2002 22.10 .87 201.6 W Mixed 2 A 6.46 142.75 .041 .904 .6 No comment.01/07/2003 20.32 .80 188.1 W Snow 3 A 8.57 174.20 .059 1.208 .7 No comment.01/14/2003 .51 .02 2.5 W Snow 3 B 9.52 4.84 Low vol Low vol -- No comment.

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-1  45
01/21/2003 1.78 0.07 0 W Snow 2 C [9.2] 16.39 Low vol Low vol -- Low volume sample; 

estimated deposition.

01/28/2003 3.30 .13 11.7 W Snow 1 A 3.97 13.11 0.253 0.837 6.4 No comment.02/04/2003 17.02 .67 164.0 W Mixed 3 A 7.12 121.32 .045 .759 .6 No comment.02/11/2003 3.30 .13 0 W Snow 3 C [9.2] 30.38 Low vol Low vol -- Low volume sample; 

estimated deposition.

02/18/2003 10.92 .43 91.0 W Snow 2 A 3.00 32.81 .079 .860 2.6 No comment.02/25/2003 27.94 1.1 161.6 W Mixed 3 A 4.27 119.33 .151 4.220 3.5 No comment.03/04/2003 2.29 .09 12.8 W Snow 2 B 6.39 14.61 .304 .696 4.8 No comment.03/11/2003 6.10 .24 48.2 W Snow 3 A 17.66 107.67 .136 .827 .8 No comment.03/18/2003 2.54 .10 17.8 W Mixed 1 A 37.55 95.39 Low vol Low vol -- No comment.03/25/2003 25.15 .99 305.8 W Rain 2 B 14.45 363.56 .120 3.012 .8 No comment.04/1/2003 26.67 1.05 334.8 W Rain 3 B 6.31 168.31 .072 1.932 1.1 No comment.04/08/2003 61.47 2.42 782.6 W Rain 2 B 9.19 565.32 Low vol Low vol -- No comment.04/15/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.

04/22/2003 3.30 .13 20.0 W Rain 5 A 13.46 44.45 .124 .411 .9 No comment.04/29/2003 8.38 .33 105.9 W Rain 2 B 19.22 161.15 .543 4.555 2.8 No comment.05/06/2003 64.13 2.52 800.9 W Rain 4 A 13.16 728.87 .085 5.455 .7 Data combined for 

05/01/2003 and 05/06/2003 samples from field audit.

05/13/2003 140.43 5.53 1,682.5 W Rain 5 B 12.49 1,753.95 .052 7.351 .4 Use bottle catch

140.43 mm to compute deposition.

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

46  Mercury in Precipitation in Indiana, January 2001–December 2003 
05/20/2003 26.16 1.03 311.8 W Rain 2 B 10.43 273.05 0.112 2.929 1.1 No comment.

05/27/2003 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.06/03/2003 25.15 .99 299.9 W Rain 3 A 21.38 537.77 .348 8.771 1.6 No comment.06/10/2003 7.37 .29 93.9 W Rain 2 A 19.36 142.60 .066 .487 .3 No comment.06/17/2003 81.03 3.19 963.2 W Rain 3 B 7.79 631.35 .067 5.395 .9 No comment.06/24/2003 .13 .01 8.6 T Trace rain 0 B -- 0 -- 0 -- No comment.07/01/2003 16.26 .64 196.6 W Rain 3 A 15.38 250.13 .189 3.081 1.2 No comment.07/08/2003 222.9 8.78 2,670.6 W Rain 4 B 11.01 2,456.13 .206 45.859 1.9 Use bottle catch

222.9 mm to computedeposition.

07/15/2003 26.67 1.05 321.0 W Rain 2 B 19.13 510.35 .106 2.835 .6 No comment.07/22/2003 20.83 .82 254.3 W Rain 1 A 16.99 353.93 .150 3.131 .9 No comment.07/29/2003 11.94 .47 142.9 W Rain 2 A 14.49 173.05 .176 2.101 1.2 No comment.08/05/2003 72.64 2.86 895.5 W Rain 4 A 11.73 852.40 .179 12.997 1.5 No comment.08/12/2003 6.86 .27 85.9 W Rain 1 A 24.23 166.23 .029 .201 .1 No comment.08/19/2003 1.52 .06 12.7 W Rain 1 A 25.15 38.33 Low vol Low vol -- No comment.08/26/2003 16.76 .66 200.1 W Rain 1 B 15.7 263.32 .059 .988 .4 No comment.09/02/2003 115.82 4.56 1,372.0 W Rain 2 B 5.79 670.85 .043 5.018 .7 No comment.09/09/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.09/16/2003 17.27 .68 214.6 W Rain 2 A 13.55 234.08 .013 .229 .1 No comment.09/23/2003 44.45 1.75 522.1 W Rain 1 B 14.58 648.25 .062 2.752 .4 No comment.09/30/2003 65.79 2.59 844.0 W Rain 3 A 13.27 873.37 .029 1.878 .20 No comment.

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-1  47
10/07/2003 5.59 0.22 57.1 W Rain 1 A 8.23 45.99 0.119 0.666 1.4 No comment.

10/14/2003 13.97 .55 176.2 W Rain 1 A 9.89 138.20 .063 .879 .6 No comment.10/21/2003 3.56 .14 39.2 W Rain 2 A 9.99 35.52 .069 .247 .7 No comment.10/28/2003 14.99 .59 176.6 W Rain 3 A 34.75 520.8 .122 1.83 .4 No comment.11/04/2003 8.38 .33 102.0 W Rain 2 B 7.48 62.76 .042 .352 .6 No comment.11/11/2003 6.10 .24 57.6 W Rain 2 A 16.64 101.46 .058 .355 .3 No comment.11/18/2003 13.97 .55 148.1 W Rain 3 A 20.02 279.72 .037 .519 .2 No comment.11/25/2003 29.46 1.16 344.3 W Mixed 2 A 8.28 244.08 .018 .536 .2 No comment.12/02/2003 11.94 .47 139.8 W Rain 2 A 4.19 50.06 .143 1.705 3.4 No comment.12/09/2003 17.78 .70 196.4 W Mixed 1 A 4.12 73.28 .041 .734 1.0 No comment.12/16/2003 17.78 .70 189.3 W Mixed 3 A 5.15 91.60 .057 1.012 1.1 No comment.12/23/2003 23.37 .92 264.9 W Mixed 2 B 4.83 112.91 .100 2.335 2.1 No comment.12/30/2003 16.51 .65 188.1 W Rain 3 B 6.43 106.25 .093 1.535 1.4 No comment.

Appendix 1-1. Weekly precipitation, total mercury, and methylmercury at Roush Lake monitoring station near Huntington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive]

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

48  Mercury in Precipitation in Indiana, January 2001–December 2003 
Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003. 

[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

01/02/2001 -- -- -- -- -- -- -- -- -- -- -- -- Sampler and rain

gage not operating.

01/09/2001 -- -- -- -- -- -- -- -- -- -- -- -- Sampler and rain

gage not operating.

01/16/2001 0.76 0.03 13.7 W Rain 3 B 17.54 13.36 0.375 0.285 2.1 No comment.01/23/2001 6.86 .27 88.5 W Mixed 3 B 4.76 32.65 .234 1.607 4.9 No comment.01/30/2001 16.57 .65 256.6 W Mixed 4 B 8.02 132.94 .048 .803 .6 No comment.02/06/2001 6.22 .24 94.5 W Mixed 3 B 7.84 48.82 .230 1.431 2.9 No comment.02/13/2001 21.08 .83 315.3 W Rain 2 B 4.13 87.19 .012 .246 .3 No comment.02/20/2001 18.29 .72 244.8 W Rain 5 B 16.96 310.31 .059 1.078 .3 No comment.02/27/2001 20.95 .82 291.9 W Rain 2 B 14.04 294.20 Low vol Low vol -- No comment.03/06/2001 10.16 .40 162.3 W Mixed 1 B 13.07 132.82 .08 .818 .6 No comment.03/13/2001 6.60 .26 99.0 W Rain 1 B 7.26 47.97 .105 .696 1.5 No comment.03/20/2001 4.32 .17 78.4 W Rain 1 B 29.44 127.12 .145 .627 .5 No comment.03/27/2001 1.27 .05 25.9 W Rain 1 B 10.23 13.00 .039 .050 .4 No comment.4/03/2001 5.08 .20 70.5 W Rain 2 B 11.93 60.61 <.009 0 -- MHg not detected.04/11/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank

sample; no Hgdetected.

04/17/2001 10.99 .43 174.9 W Mixed 3 B 28.43 312.34 .280 3.076 1.0 No comment.04/24/2001 12.32 .49 193.3 W Rain 2 B 20.71 255.17 .188 2.315 .9 No comment.05/1/2001 0 0 (2.5) D Dry 0 B -- 0 -- 0 -- No comment.

Appendix 1-2  49
05/08/2001 27.69 1.09 379.5 W Rain 3 B 22.71 628.94 0.075 2.088 0.3 No comment.

05/15/2001 24.64 .97 324.7 W Rain 1 B 6.86 169.21 .022 .551 .3 No comment.05/22/2001 33.08 1.30 492.4 W Rain 3 B 7.83 259.30 .032 1.074 .4 No comment.05/29/2001 21.72 .86 307.9 W Rain 4 B 9.44 205.09 .012 .253 .1 No comment.06/05/2001 22.61 .89 306.4 W Rain 4 B 19.75 446.58 <.016 0 -- MHg not detected06/12/2001 9.78 .39 14.1 W Rain 1 B 18.17 177.75 <.016 0 -- MHg not detected06/19/2001 15.24 .60 232.8 W Rain 1 B 15.67 238.94 <.016 0 -- MHg not detected06/26/2001 7.55 .30 90.4 W Rain 3 B 29.51 222.71 <.016 0 -- Use bottle catch

7.55 mm tocomputedeposition; MHgnot detected.

070/3/2001 12.95 .51 149.1 W Rain 3 B 13.00 168.42 <.016 0 -- MHg not detected07/10/2001 64.52 2.54 824.8 W Rain 3 B 16.84 1,086.57 .035 2.277 .2 No comment.07/17/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank

sample; no Hgdetected.

7/24/2001 33.53 1.32 467.8 W Rain 2 B 21.16 709.68 .025 .852 .1 No comment.7/31/2001 31.75 1.25 434.8 W Rain 2 B 3.74 118.74 .028 .875 .7 No comment.8/7/2001 5.21 .21 80.6 W Rain 2 B 9.14 47.61 <.021 0 -- MHg not detected.8/14/2001 3.30 .13 50.0 W Rain 1 B 11.05 36.51 <.021 0 -- MHg not detected.8/21/2001 42.16 1.66 544.6 W Rain 2 B 5.46 230.30 .054 2.274 1.0 No comment.8/28/2001 15.24 .60 224.8 W Rain 2 B 12.27 186.99 .059 .896 .5 No comment.9/4/2001 9.91 .39 145.7 W Rain 1 B 13.02 129.05 <.019 0 -- MHg not detected.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

50 Mercury in Precipitation in Indiana, January 2001–December 2003 
9/11/2001 55.37 2.18 715.9 W Rain 3 B 10.32 571.60 <0.019 0 -- MHg not detected.

9/18/2001 1.27 .05 28.0 W Rain 1 B 11.21 14.23 .470 .597 4.2 No comment.9/25/2001 36.32 1.43 499.4 W Rain 2 B 7.63 277.17 .009 .332 .1 No comment.10/2/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank

sample; no Hgdetected.

10/9/2001 24.64 .97 317.9 W Rain 1 B 2.75 67.95 <.019 0 -- MHg not detected10/16/2001 75.18 2.96 907.6 W Rain 3 B 12.89 969.64 .014 1.019 .1 No comment.10/23/2001 56.64 2.23 720.2 W Rain 1 B 8.38 474.94 .003 .174 0 No comment.10/30/2001 12.19 .48 0 W Rain 1 C [12.1] 147.61 [.029] .354 .2 Estimated THg and

MHg deposition.

11/06/2001 0 0 (2.2) D Dry 0 B -- 0 -- 0 -- No comment.

11/13/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

11/20/2001 9.35 .37 112.0 W Rain 1 B 5.94 55.55 .031 .289 .5 Use bottle catch 

9.35 mm tocomputedeposition.

11/27/2001 22.86 .90 302.0 W Rain 2 B 11.83 270.61 .014 .323 .1 No comment.12/04/2001 62.23 2.45 787.3 W Rain 1 B 10.00 622.3 .027 1.666 .3 No comment.12/11/2001 21.59 .85 293.6 W Rain 2 B 6.82 147.24 .090 1.934 1.3 No comment.12/18/2001 76.20 3.00 943.7 W Rain 3 B 22.34 1,702.68 .017 1.332 .1 No comment.12/25/2001 17.78 .70 256.4 W Rain 1 B 8.72 155.05 .183 3.256 2.1 No comment.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-2  51
01/01/2002 0.88 0.03 (10.5) W Mixed 3 C [11.66] 10.27 [0.034] 0.030 0.3 Estimated deposition

with bottle catch

0.88 mm.

01/08/2002 7.35 .29 88.1 W Snow 2 B 4.37 32.19 .058 .427 1.3 Use bottle catch

7.35 mm tocomputedeposition.

01/15/2002 0 0 ( 6) D Dry . 0 B -- 0 -- 0 -- No comment.

01/22/2002 1.27 .05 33.6 W Snow 1 B 4.11 5.23 .080 .102 1.9 No comment.01/29/2002 24.13 .95 323.0 W Rain 1 B 7.94 191.61 .020 .483 .3 No comment.02/05/2002 40.01 1.58 511.5 W Rain 2 B 6.33 253.27 Low vol Low vol -- No comment.02/12/2002 6.03 .24 70.1 W Rain 1 B 9.17 55.34 Low vol Low vol -- No comment.02/19/2002 0 0 0 D Dry 0 C -- 0 -- 0 -- Rain gage clock

stopped; alternaterain gages recordedzero precipitation.

02/26/2002 28.50 1.12 341.4 W Mixed 3 B 13.15 374.90 .071 2.025 .5 Use bottle catch

28.5 mm to computedeposition.

03/05/2002 16.00 .63 220.8 W Rain 1 B 13.08 209.30 .002 .032 0 No comment.03/12/2002 12.83 .51 163.1 W Rain 1 B 30.97 397.34 .037 .475 .1 No comment.03/19/2002 52.07 2.05 658.0 W Rain 3 B 14.41 750.79 .019 .990 .1 No comment.03/26/2002 29.21 1.15 383.1 W Rain 1 B 9.62 281.26 .098 2.865 1.0 No comment.04/02/2002 .51 .02 12.5 W Rain 2 B 66.5 33.78 .135 .069 .2 No comment.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

52 Mercury in Precipitation in Indiana, January 2001–December 2003 
040/9/2002 8.26 0.33 139.1 W Rain 2 B 15.07 124.42 0.021 0.170 0.1 No comment.

04/16/2002 30.04 1.18 391.2 W Rain 2 B 9.26 278.37 .017 .521 .2 No comment.04/23/2002 82.80 3.26 1,063.3 W Rain 3 B 10.47 867.70 .029 2.406 .3 No comment.04/30/2002 51.31 2.02 646.5 W Rain 2 B 10.53 540.58 .076 3.886 .7 No comment.05/07/2002 52.83 2.08 695.6 W Rain 4 B 17.66 933.06 .089 4.710 .5 No comment.05/14/2002 120.65 4.75 1,545.8 W Rain 3 B 10.49 1,266.34 .142 17.183 1.4 No comment.05/21/2002 20.07 .79 255.9 W Rain 1 B 51.67 1,036.81 2.71 54.433 5.3 No comment.05/28/2002 25.15 .99 305.4 W Rain 2 B 15.74 396.02 .053 1.344 .3 No comment.06/04/2002 6.10 .24 91.4 W Rain 2 B 21.25 129.59 .005 .033 0 No comment.06/11/2002 30.23 1.19 387.9 W Rain 1 B 13.71 414.54 .433 13.097 3.2 No comment.06/18/2002 26.16 1.03 381.1 W Rain 3 B 15.41 403.15 .069 1.811 .4 No comment.06/25/2002 29.72 1.17 371.6 W Rain 1 B 15.19 451.50 .011 .332 .1 No comment.070/2/2002 21.34 .84 258.8 W Rain 1 B 13.70 292.36 .042 .897 .3 No comment.070/9/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.07/16/2002 24.38 .96 355 W Rain 2 B 14.81 361.20 .046 1.116 .3 No comment.07/23/2002 46.48 1.83 643.2 W Rain 4 B 17.75 825.42 Low vol Low vol -- No comment.07/30/2002 4.06 .16 63.1 W Rain 2 B 19.84 80.62 Low vol Low vol -- No comment.08/06/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

08/13/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

08/20/2002 37.72 1.49 490.4 W Rain 2 B 6.46 243.92 .042 1.591 .7 No comment.08/27/2002 2.29 .09 24.4 W Rain 1 B 26.36 60.26 .075 .172 .3 No comment.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-2  53
090/3/2002 2.29 0.09 23.5 W Rain 4 B 31.37 71.73 Low vol Low vol -- No comment.

09/10/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

09/17/2002 16.51 .65 216.5 W Rain 1 B 16.37 270.31 Low vol Low vol -- No comment.09/24/2002 13.72 .54 180.9 W Rain 2 B 30.20 414.22 Low vol Low vol -- No comment.10/01/2002 171.32 6.74 2,287.7 W Rain 1 A 2.25 385.47 0.011 1.888 0.5 No comment.10/08/2002 11.18 .44 152.6 W Rain 1 B 13.96 156.02 .005 .053 0 No comment.10/15/2002 8.89 .35 118.6 W Rain 1 B 2.10 18.66 .020 .174 .9 No comment.10/22/2002 8.00 .31 110.9 W Rain 1 A 25.55 204.42 .087 .696 .3 No comment.10/29/2002 50.8 2.00 644.3 W Rain 3 A 12.27 623.77 .002 .105 0 No comment.11/05/2002 .76 .03 25.8 W Rain 1 B 17.80 13.52 .058 .044 .3 Use bottle catch

0.76 mm to computedeposition.

11/12/2002 54.02 2.13 647.2 W Rain 3 B 11.17 603.54 .011 .607 .1 Use bottle catch

54.02 mm to computedeposition.

11/19/2002 4.78 .19 53.8 W Rain 2 A 6.59 31.36 .183 .874 2.8 No comment.11/26/2002 7.87 .31 105.0 W Rain 1 A 4.49 35.37 .177 1.392 3.9 No comment.12/03/2002 0 0 (.9)

D Dry 0 B -- 0 -- 0 -- No comment.

12/10/2002 6.99 .28 66.4 W Snow 1 A 5.38 37.62 .015 .108 .3 No comment.12/17/2002 27.81 1.09 342.5 W Mixed 3 B 6.51 181.20 .133 3.706 2.0 No comment.12/24/2002 44.45 1.75 607.0 W Rain 2 A 1.19 453.12 .038 1.709 .4 No comment.12/31/2002 22.35 .88 311.7 W Rain 2 A 7.78 174.07 .076 1.695 1.0 No comment.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

54  Mercury in Precipitation in Indiana, January 2001–December 2003 
01/07/2003 40.77 1.61 530 W Mixed 2 A 4.82 196.86 0.103 4.187 2.1 No comment.

01/14/2003 .38 .01 7.5 W Snow 1 B 1.10 3.85 Low vol Low vol -- Low volume sample.01/21/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.

01/28/2003 .70 .03 8.4 W Snow 1 B 2.94 14.68 .025 .017 .1 Use bottle catch

0.7mm to computedeposition.

02/04/2003 11.30 .44 152.2 W Mixed 3 B 4.51 5.98 .084 .949 1.9 No comment.02/11/2003 7.28 .29 87.2 W Snow 3 B 5.65 41.14 .044 .322 .8 Use bottle catch

7.28 mm tocomputedeposition.

02/18/2003 33.53 1.32 321.9 W Mixed 2 B 9.84 33.18 .167 5.593 1.7 No comment.02/25/2003 37.97 1.49 431.0 W Mixed 5 B 15.61 592.83 .032 1.222 .2 No comment.03/04/2003 .89 .04 12.0 W Snow 3 A 14.62 13.0 .273 .243 1.9 No comment.03/11/2003 1.27 .05 23.3 W Rain 2 A 13.17 16.73 Low vol Low vol -- No comment.03/18/2003 7.87 .31 123.4 W Rain 2 A 16.06 126.51 Low vol Low vol -- No comment.03/25/2003 11.43 .45 161.5 W Rain 2 B 17.47 199.69 .078 .890 .4 No comment.04/01/2003 19.3 .76 280.2 W Rain 2 A 7.88 152.28 .086 1.662 1.1 No comment.04/08/2003 22.23 .88 286.5 W Rain 2 B 1.79 239.94 .046 1.021 .4 No comment.04/15/2003 .64 .03 16.1 W Rain 1 A 23.76 15.09 .315 .202 1.3 No comment.04/22/2003 52.2 2.06 659.4 W Rain 3 B 15.42 805.19 .070 3.639 .5 No comment.04/29/2003 24.89 .98 324.2 W Rain 3 B 12.12 301.79 .155 3.860 1.3 No comment.05/06/2003 58.17 2.29 684.1 W Rain 1 B 13.8 802.69 .090 5.254 .7 No comment.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-2  55
05/13/2003 75.18 2.96 952.3 W Rain 3 B 21.34 1,604.65 0.088 6.644 0.4 No comment.

05/20/2003 54.48 2.14 637.8 W Rain 4 B 11.28 615.05 .063 3.440 .6 No comment.05/27/2003 3.05 .12 39.8 W Rain 1 A 12.57 38.32 .212 .648 1.7 No comment.06/03/2003 27.43 1.08 324.2 W Rain 2 B 16.41 45.15 .199 5.451 1.2 No comment.06/10/2003 5.08 .20 58.1 W Rain 3 B 18.46 93.80 .006 .031 0 No comment.06/17/2003 36.83 1.45 469.4 W Rain 3 A 16.98 625.66 .050 1.851 .3 No comment.06/24/2003 4.83 .19 52.6 W Rain 1 A 6.15 29.70 .215 1.041 3.5 No comment.07/1/2003 29.46 1.16 373.5 W Rain 1 B 7.33 216.03 .028 .816 .4 No comment.07/08/2003 13.46 .53 164.4 W Rain 1 B 24.06 323.89 .046 .620 .2 No comment.07/15/2003 91.19 3.59 1,148.4 W Rain 3 B 22.4 2,042.93 .051 4.635 .2 No comment.07/22/2003 42.67 1.68 528.2 W Rain 2 B 12.56 536.04 .088 3.738 .7 No comment.07/29/2003 82.80 3.26 994.5 W Rain 2 B 9.68 802.20 .081 6.739 .8 No comment.08/05/2003 9.65 .38 132.2 W Rain 2 B 18.78 181.30 .060 .578 .3 No comment.08/12/2003 28.19 1.11 363.5 W Rain 3 B 23.93 674.76 .047 1.328 .2 No comment.08/19/2003 .13 .01 0 T Trace rain 0 A -- 0 -- 0 -- No comment.08/26/2003 1.78 .07 15.1 W Rain 1 B 3.29 53.85 Low vol Low vol

No comment.

09/02/2003 165.74 6.53 2,345.3 W Rain 5 A 1.65 1,765.74 .023 3.766 .2 No comment.09/09/2003 11.68 .46 134.9 W Rain 1 A 5.62 65.69 .001 .006 0 No comment.09/16/2003 7.37 .29 91.5 W Rain 1 B 19.28 142.03 .061 .448 .3 No comment.09/23/2003 35.31 1.39 408.6 W Rain 1 A 15.31 54.74 .013 .468 .1 No comment.09/30/2003 16.89 .66 202.3 W Rain 2 B 16.94 286.25 .039 .666 .2 No comment.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

56  Mercury in Precipitation in Indiana, January 2001–December 2003 
10/07/2003 6.10 0.24 90.5 W Rain 2 A 9.05 55.21 0.145 0.887 1.6 No comment.

10/14/2003 21.34 .84 262.2 W Rain 2 B 5.16 11.24 .033 .703 .6 No comment.10/21/2003 2.54 .10 19.1 W Rain 1 A 3.03 76.29 .218 .555 .7 No comment.10/28/2003 26.67 1.05 329.3 W Rain 1 B 32.57 868.85 .065 1.728 .2 No comment.11/04/2003 3.30 .13 47.4 W Rain 3 A 4.01 13.24 .180 .596 4.5 No comment.11/11/2003 35.56 1.40 428.7 W Rain 2 A 11.42 406.13 .048 1.702 .4 No comment.11/18/2003 10.90 .43 130.6 W Rain 2 B 5.15 56.22 .312 3.400 6.0 Use bottle catch

10.9 mm tocomputedeposition.

11/25/2003 36.57 1.44 438.1 W Rain 2 B 4.88 178.77 .009 .346 .2 Use bottle catch

36.57 mm tocomputedeposition.

12/02/2003 31.75 1.25 391.1 W Rain 1 A 3.36 106.74 .101 3.201 3.0 No comment.12/09/2003 9.40 .37 88.3 W Rain 1 A 13.06 122.73 .103 .971 .8 No comment.12/16/2003 23.11 .91 258.6 W Mixed 2 A 5.35 123.70 .053 1.219 1.0 No comment.12/23/2003 10.16 .40 104.8 W Mixed 4 A 8.91 9.57 .141 1.437 1.6 No comment.12/30/2003 22.61 .89 300.1 W Rain 2 A 4.32 97.86 Low vol Low vol -- No comment.

Appendix 1-2. Weekly precipitation, total mercury, and methylmercury at Clifty Falls monitoring station near Madison, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-2  57
58  Mercury in Precipitation in Indiana, January 2001–December 2003 Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003. [mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] Date sample removed Precipi- tation (mm) Precipi- tation (in.) Sample volume (mL) Sample type Precipi- tation type Wet depo- sition events Data- quality rating Total mercury concen- tration (ng/L) Total mercury deposition (ng/m2) Methyl- mercury concen- tration (ng/L) Methyl- mercury deposition (ng/m2) Ratio methyl- mercury to total mercury (percent) Comments 01/02/2001 0.89 0.04 7.9 W Snow 1 B 15.09 13.42 0.87 0.77 5.8 No comment. 01/09/2001 0 0 0 D QC 0 B -- 0 -- 0 -- Field bottle blank; no Hg detected. 01/16/2001 1.52 .06 5.1 W Snow 1 B 1.97 16.73 Low vol Low vol -- No comment. 01/23/2001 1.02 .04 2.7 W Snow 1 B 7.37 7.49 Low vol Low vol -- No comment. 01/30/2001 23.94 .94 230.0 W Mixed 4 B 7.79 186.60 .102 2.44 1.3 No comment. 02/06/2001 9.52 .37 118.0 W Mixed 5 B 6.96 66.35 .15 1.43 2.2 No comment. 02/13/2001 26.67 1.05 306.9 W Rain 2 B 3.69 98.57 <.012 0 -- MHg not detected.

02/20/2001 5.46 .21 72.5 W Rain 4 B 6.13 33.49 .062 .34 1.0 No comment.02/27/2001 21.46 .84 238.4 W Mixed 1 B 6.31 135.60 .016 .34 .3 No comment.03/06/2001 .38 .01 2.3 W Mixed 1 B 26.91 1.25 Low vol Low vol -- No comment.03/13/2001 4.57 .18 57.6 W Rain 1 B 1.98 5.20 .041 .19 .4 No comment.03/20/2001 6.35 .25 9.2 W Rain 1 A 4.88 31.03 .057 .36 1.2 No comment.03/27/2001 .38 .01 5.9 W Rain 1 B 23.50 8.95 Low vol Low vol -- No comment.04/03/2001 6.54 .26 76.0 W Rain 2 B 7.24 47.36 .092 .6 1.3 No comment.04/10/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

04/17/2001 35.37 1.39 423.8 W Rain 4 B 21.20 75.09 .03 1.06 .1 Use bottle catch

35.37 mm tocompute deposition.

04/24/2001 1.59 .42 69.0 W Rain 3 B 15.09 159.85 <.009 0 -- MHg not detected.

05/1/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.
Appendix 1-3  59

05/08/2001 11.37 0.45 128.0 W Rain 1 B 1.83 123.09 0.057 0.64 0.5 No comment.05/15/2001 5.08 .20 55.0 W Rain 1 B 18.18 92.37 .094 .48 .5 No comment.05/22/2001 3.16 1.19 355.5 W Rain 4 B 9.06 273.41 .036 1.07 .4 No comment.05/29/2001 32.77 1.29 406.6 W Rain 3 B 1.23 335.19 .008 .27 .1 No comment.06/05/2001 54.48 2.14 697.4 W Rain 4 B 16.94 922.94 .02 1.10 .1 No comment.06/12/2001 18.42 .73 21.2 W Rain 1 B 15.07 277.62 .019 .35 .1 No comment.06/19/2001 17.40 .69 191.8 W Rain 1 B 9.40 163.67 .003 .05 0 No comment.06/26/2001 25.91 1.02 32.1 W Rain 2 B 16.03 415.35 .048 1.24 .3 No comment.07/03/2001 13.27 .52 147.5 W Rain 2 B 11.38 151.11 .01 .14 .1 No comment.07/10/2001 104.65 4.12 1,245.4 W Rain 4 B 11.25 1,178.02 .011 1.20 .1 No comment.07/17/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

07/24/2001 32.96 1.30 39.7 W Rain 3 B 24.33 802.07 .028 .91 .1 No comment.07/31/2001 122.43 4.82 124.6 W Rain 4 B 9.43 1,155.23 .007 .82 .1 No comment.08/07/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

08/14/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.08/21/2001 23.88 .94 289.3 W Rain 2 B 12.11 289.13 .041 .98 .3 No comment.08/28/2001 36.58 1.44 417.0 W Rain 2 B 13.93 509.65 .079 2.90 .6 No comment.09/04/2001 19.56 .77 225.8 W Rain 1 B 11.06 216.48 .029 .56 .3 No comment.09/11/2001 51.05 2.01 56.3 W Rain 2 B 15.38 785.31 <.019 0 -- MHg not detected.

09/18/2001 5.33 .21 64.8 W Rain 1 B 14.90 79.50 <.019 0 -- MHg not detected.

09/25/2001 26.42 1.04 302.7 W Rain 2 B 9.53 251.79 .028 .74 .3 No comment.

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments
6

0 Mercury in Precipitation in Indiana, January 2001–December 2003 10/02/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment. 10/09/2001 15.24 .60 186.2 W Rain 1 B 5.19 79.12 0.005 .07 0.1 No comment. 10/16/2001 103.38 4.07 1,258.5 W Rain 4 B 5.92 612.30 .003 .31 .1 No comment. 10/23/2001 1.27 .05 13.9 W Rain 2 B 13.12 16.67 .244 .31 1.9 No comment. 10/30/2001 71.37 2.81 874.6 W Rain 2 B 8.76 625.80 .004 .26 0 No comment. 11/6/2001 2.03 .08 25.4 W Rain 1 B 27.60 56.09 .219 .45 .8 No comment. 11/13/2001 .25 .01 1.4 T Trace rain 0 B -- 0 Low vol Low vol -- No comment. 11/20/2001 4.45 .18 48.0 W Rain 1 B 13.30 59.14 .159 .71 1.2 No comment. 11/27/2001 38.10 1.50 482.1 W Rain 2 B 5.02 191.37 .009 .35 .2 No comment.

12/04/2001 48.01 1.89 589.1 W Rain 3 B 4.02 192.98 .051 2.44 1.3 No comment.12/11/2001 7.87 .31 93.2 W Rain 1 B 9.46 74.52 .054 .42 .6 No comment.12/18/2001 88.01 3.46 993.6 W Rain 3 B 4.53 399.12 .031 2.72 .7 No comment.12/24/2001 3.91 .15 49.0 W Rain 1 B 9.89 38.69 .158 .62 1.6 No comment.12/31/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

01/08/2002 4.83 .19 47.7 W Snow 1 B 3.31 16.01 .103 .50 3.1 No comment.01/15/2002 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

01/22/2002 1.27 .05 8.9 W Snow 1 B 3.37 4.28 .335 .43 9.9 No comment.01/28/2002 13.59 .54 165.6 W Rain 1 B 5.86 79.63 .026 .35 .4 No comment.02/05/2002 56.39 2.22 0 W Rain 1 C [5.95] 355.77 Low vol Low vol -- Estimated THg

deposition.

02/12/2002 6.60 .26 71.5 W Rain 1 B 3.40 22.47 .087 .57 2.6 No comment.

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments
Appendix 1-3  6

1

02/19/2002 0.25 0.01 1.9 W Rain 1 B 47.03 11.94 Low vol Low vol -- Low volume sample.02/26/2002 28.32 1.11 (334.0) W Mixed 2 C {9.18} 26.17 [0.036] 1.02 0.4 Estimated THg and

MHg deposition withrain-gage amountand subsampleconcentration.

03/05/2002 14.73 .58 167.4 W Rain 1 B 2.90 42.73 .089 1.31 3.1 No comment.03/12/2002 29.21 1.15 (166.7) W Rain 2 C 7.91 231.22 [.028] .82 .4 Estimated THg and

MHg deposition withrain gage-amountand subsampleconcentration.

03/19/2002 14.48 .57 182.9 W Rain 3 B 12.57 181.98 .040 .58 .3 No comment.03/26/2002 48.77 1.92 622.2 W Mixed 3 B 1.04 489.63 .052 2.54 .5 No comment.04/02/2002 4.83 .19 (36.8) W Rain 2 C [10.86] 52.49 [.059] .29 .5 Estimated THg and

MHg deposition.

04/09/2002 28.45 1.12 (337.5) W Rain 2 C [10.86] 309.20 [.059] 1.68 .5 Estimated THg and

MHg deposition.

04/16/2002 48.39 1.91 603.6 W Rain 2 C 7.91 382.98 .026 1.28 .3 Sampler open two dry

days; repaired andOK for rains; use for summary.

04/23/2002 38.10 1.50 450.0 W Rain 1 B 1.71 408.16 .011 .42 .1 No comment.04/29/2002 52.83 2.08 594.1 W Rain 2 B 1.17 537.35 .078 4.13 .8 No comment.05/07/2002 63.25 2.49 717.9 W Rain 3 B 16.85 1,066.07 .176 11.17 1.0 No comment.05/14/2002 107.19 4.22 1,258.0 W Rain 2 B 9.18 984.09 .026 2.78 .30 No comment.

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments
6

2 Mercury in Precipitation in Indiana, January 2001–December 2003 05/21/2002 1.16 0.40 104.6 W Rain 2 B 9.75 99.13 0.028 0.28 0.3 No comment. 05/28/2002 20.00 .79 207.4 W Rain 2 B 13.81 276.42 .041 .81 .3 No comment. 06/04/2002 6.86 .27 68.9 W Rain 3 B 15.94 109.35 .003 .02 0 No comment. 06/11/2002 56.13 2.21 626.6 W Rain 1 B 1.64 597.26 .080 4.49 .8 No comment. 06/18/2002 54.10 2.13 622.9 W Rain 3 B 9.87 534.20 .037 1.99 .4 No comment. 06/25/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment. 07/02/2002 25.78 1.01 319.3 W Rain 2 B 1.86 280 .017 .43 .2 No comment. 07/09/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment. 07/16/2002 22.35 .88 249.2 W Rain 1 B 2.30 453.94 .144 3.21 .7 No comment.

07/23/2002 41.40 1.63 489.5 W Rain 2 B 25.83 1,069.41 .055 2.29 .2 No comment.07/30/2002 12.45 .49 14.2 W Rain 2 B 13.71 17.74 .016 .2 .1 No comment.08/06/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.08/13/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.08/20/2002 32.51 1.28 401.7 W Rain 4 B 11.10 361.01 .020 .67 .2 No comment.08/27/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.09/03/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.09/10/2002 1.27 .05 4.1 W Rain 1 B 76.96 97.74 Low vol Low vol -- No comment.09/17/2002 22.10 .87 242.8 W Rain 1 B 18.21 402.53 .004 .08 0 No comment.09/24/2002 59.69 2.35 (661.9) W Rain 3 C [17.48] 1,044.15 [.043] 2.57 .25 Estimated THg and

MHg deposition.

10/01/2002 32.51 1.28 234.1 W Rain 1 B 7.83 254.55 .001 .04 .0 No comment.

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments
Appendix 1-3  6

3

10/08/2002 21.59 0.85 254.9 W Rain 1 A 4.79 103.61 0.006 0.13 0.1 Data combined for 

10/05/2002 and10/08/2002 samples

from field audit.

10/15/2002 .51 .02 5.8 W Rain 2 B 5.91 3.00 Low vol Low vol -- Low volume sample.10/22/2002 15.11 .59 166.0 W Rain 1 B 7.64 115.44 .038 .57 .5 No comment.10/29/2002 57.66 2.27 (455.4) W Rain 1 C [6.90} 398.15 [.031] 1.79 .4 Estimated THg and

MHg deposition.

11/05/2002 11.18 .44 148.1 W Rain 3 B 8.78 98.22 .023 .26 .3 No comment.11/12/2002 25.91 1.02 295.2 W Rain 2 B 9.75 252.62 Low vol Low vol -- No comment.11/18/2002 1.27 .05 9.0 W Rain 1 B 4.41 5.61 Low vol Low vol -- No comment.11/26/2002 13.08 .51 134.5 W Rain 2 A 2.52 33.01 .066 .86 2.6 No comment.12/03/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

12/10/2002 3.81 .15 (3.6) W Snow 1 C [6.90] 26.31 Low vol Low vol -- Estimated THg

deposition.

12/17/2002 18.42 .73 131.8 W Mixed 3 B 7.29 134.30 .061 1.13 .8 No comment.12/24/2002 37.72 1.49 447.0 W Rain 3 A 6.12 231.14 .064 2.43 1.0 No comment.12/31/2002 23.11 .91 235.8 W Mixed 3 A 9.29 214.72 .051 1.18 .5 No comment.01/07/2003 15.75 .62 206.0 W Mixed 2 A 4.17 65.70 .123 1.93 2.9 No comment.01/14/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.

01/21/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.01/28/2003 1.27 .05 0 W Snow 1 C [6.45] 8.20 Low vol Low vol -- Low volume sample;

estimated THgdeposition.

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments
64  Mercury in Precipitation in Indiana, January 2001–December 2003 02/04/2003 1.03 0.39 105.0 W Snow 2 A 4.43 44.52 0.045 0.45 1.0 No comment. 02/11/2003 6.10 .24 11.2 W Snow 2 A 5.73 34.96 .079 .48 1.4 No comment. 02/18/2003 25.91 1.02 204.2 W Mixed 3 B 1.17 263.66 .179 4.65 1.8 No comment. 02/25/2003 28.45 1.12 312.6 W Snow 5 B 2.18 62.21 .112 3.19 5.1 No comment. 03/04/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment. 03/11/2003 7.62 .30 22.0 W Snow 2 A 9.15 69.77 Low vol Low vol -- No comment. 03/18/2003 12.45 .49 63.0 W Rain 1 A 16.71 208.02 Low vol Low vol -- No comment. 03/25/2003 14.22 .56 (16.7) W Rain 1 C {4.13} 58.77 {.186} 2.64 4.5 Low capture; estimated THg and MHg deposition with raingage amount and

subsampleconcentration.

04/01/2003 29.21 1.15 217.9 W Rain 2 A 3.64 106.50 .055 1.60 1.5 No comment.04/08/2003 11.56 .46 133.2 W Rain 2 A 13.59 157.10 .131 1.51 1.0 No comment.04/15/2003 .25 .01 1.2 T Trace rain 0 B -- 0 -- 0 -- No comment.

04/22/2003 39.62 1.56 343.7 W Rain 2 A 8.38 332.04 .057 2.28 .7 No comment.04/29/2003 43.69 1.72 527.9 W Rain 2 B 1.95 478.42 .097 4.26 .9 No comment.05/06/2003 64.52 2.54 725.1 W Rain 2 B 12.70 819.35 .035 2.28 .3 No comment.05/13/2003 43.43 1.71 51.2 W Rain 5 B 11.53 501.05 .069 3 .6 No comment.05/20/2003 18.54 .73 217.9 W Rain 3 A 15.64 289.99 .059 1.09 .4 No comment.05/27/2003 0 0 0 D QC 0 A <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

06/03/2003 25.91 1.02 29.6 W Rain 3 A 16.00 414.65 .211 5.46 1.3 No comment.

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments
Appendix 1-3  65

06/10/2003 1.27 0.05 12.2 W Rain 2 A 17.78 22.58 -- 0 -- No comment.06/17/2003 97.79 3.85 1,248.3 W Rain 4 B 5.35 523.37 0.032 3.10 0.6 No comment.06/24/2003 9.65 .38 116.2 W Rain 1 A 5.47 52.85 .120 1.16 2.2 No comment.07/01/2003 0.51 0.02 9.4 W Rain 1 B 16.99 8.63 Low vol Low vol -- Low volume sample.07/08/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.

07/15/2003 117.09 4.61 1,384.7 W Rain 2 B 12.50 1,464.61 .037 4.35 .3 No comment.07/22/2003 81.79 3.22 93.5 W Rain 3 A 14.89 1,218.15 .125 1.25 .8 No comment.07/29/2003 2.57 .81 229.9 W Rain 1 B 13.94 286.86 .121 2.49 .9 No comment.08/05/2003 6.35 .25 69.9 W Rain 1 A 17.75 112.76 .135 .86 .8 No comment.08/12/2003 1.02 .04 11.9 W Rain 1 A 24.97 25.37 Low vol Low vol -- No comment.08/19/2003 .13 .01 .3 T Trace rain 0 B -- 0 -- 0 -- No comment.

08/26/2003 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

09/02/2003 136.65 5.38 1,641.6 W Rain 3 A 7.14 976.24 .013 1.83 .2 No comment.09/09/2003 .25 .01 0 T Trace rain 0 B -- 0 -- 0 -- No comment.

09/16/2003 1.27 .05 9.2 W Rain 2 B 9.58 12.16 .336 .43 3.5 No comment.09/23/2003 26.67 1.05 331.1 W Rain 1 A 1.08 268.96 .058 1.55 .6 No comment.09/30/2003 28.70 1.13 319.1 W Rain 2 A 1.37 297.64 .027 .78 .3 No comment.10/07/2003 1.52 .06 9.6 W Rain 1 B 32.37 49.33 .223 .34 .7 No comment.10/14/2003 3.99 1.22 36.5 W Rain 1 A 5.66 175.57 .039 1.21 .7 No comment.10/21/2003 5.84 .23 71.8 W Rain 1 A 12.12 7.85 .079 .46 .7 No comment.10/28/2003 17.65 .69 190.0 W Rain 1 A 11.27 198.96 .120 2.12 1.1 No comment.

Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wet

deposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments
66  Mercury in Precipitation in Indiana, January 2001–December 2003 11/04/2003 1.80 0.43 131.2 W Rain 2 B 8.95 96.71 0.018 0.20 0.2 No comment. 11/11/2003 6.10 .24 59.5 W Rain 3 A 17.15 104.58 .045 .28 .3 No comment. 11/18/2003 42.55 1.68 431.5 W Rain 3 B 1.42 443.61 .045 1.91 .4 No comment. 11/26/2003 4.89 1.61 369.1 W Rain 2 B 5.04 206.47 .019 .80 .4 No comment. 12/02/2003 53.59 2.11 566.1 W Rain 2 A 11.61 622.65 .065 3.48 .6 No comment. 12/09/2003 7.37 .29 24.9 W Mixed 1 A 2.58 19.01 .109 .80 4.2 No comment. 12/16/2003 19.81 .78 143.6 W Mixed 3 A 7.25 143.71 .062 1.22 .8 No comment. 12/23/2003 16.00 .63 137.8 W Mixed 3 A 6.14 98.38 .105 1.68 1.7 No comment. 12/30/2003 11.18 .44 91.7 W Rain 1 A 4.88 54.62 Low vol Low vol -- No comment. Appendix 1-3. Weekly precipitation, total mercury, and methylmercury at Bloomington monitoring station near Bloomington, Indiana, January 2001–December 2003.—Continued [mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; braces, concentration from a subsample of weekly precipitation sample; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] Date sample removed Precipi- tation (mm) Precipi- tation (in.) Sample volume (mL) Sample type Precipi- tation type Wet depo- sition events Data- quality rating Total mercury concen- tration (ng/L) Total mercury deposition (ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments
Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003. 

[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

1/1/2001 17.97 0.71 44.1 W Snow 2 B 8.89 159.87 0.071 1.28 0.8 No comment.1/9/2001 1.78 .07 122.4 W Mixed 1 C [1.1] 17.99 Low vol Low vol Estimated THg

deposition.

1/16/2001 3.11 .12 42.5 W Mixed 1 B 2.44 7.60 .241 .75 9.9 No comment.

1/23/2001 .25 .01 .1 T Trace mixed 0 B -- 0 -- 0 -- No comment.

1/30/2001 16.51 .65 204.9 W Mixed 4 B 9.67 159.68 .202 3.34 2.1 No comment.2/6/2001 8.38 .33 38.2 W Mixed 5 B 9.74 81.70 .126 1.06 1.3 No comment.2/13/2001 26.67 1.05 323.8 W Mixed 1 B 11.48 306.38 .005 .13 0 No comment.2/20/2001 3.81 .15 45.8 W Rain 2 B 1.98 41.84 .058 .22 .5 No comment.

2/27/2001 51.31 2.02 539.3 W Rain 1 B 7.04 361.41 .040 2.05 .6 No comment.3/6/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

3/13/2001 6.35 .25 96.7 W Mixed 3 B 17.08 108.51 .214 1.36 1.3 No comment.3/20/2001 11.43 .45 158.3 W Mixed 2 B 16.06 183.60 .030 .34 .2 No comment.3/27/2001 .51 .02 4.0 W Rain 1 B 29.57 15.02 Low vol Low vol -- Use bottle catch

0.51 mm tocomputedeposition.

4/3/2001 4.57 .18 53.0 W Rain 1 B 2.24 92.56 .171 .78 .8 No comment.

4/10/2001 18.29 .72 245.1 W Rain 3 B 27.79 508.29 .040 .74 .1 No comment.4/17/2001 21.08 .83 274.0 W Rain 2 B 15.45 325.84 .035 .74 .2 No comment.4/24/2001 13.40 .53 20.4 W Rain 4 B 22.05 295.47 .079 1.05 .4 No comment.5/1/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

Appendix 1-4  67
5/8/2001 4.32 0.17 0 W Rain 3 C [16.4] 7.90 [0.062] 0.27 0.4 Estimated THg and

MHg deposition.

5/15/2001 29.97 1.18 333.7 W Rain 3 B 17.26 517.43 .114 3.43 .7 No comment.5/22/2001 6.4 .25 76.7 W Rain 1 B 31.50 201.70 .085 .54 .3 Use bottle catch

6.4 mm to computedeposition.

5/29/2001 39.62 1.56 546.8 W Rain 4 B 8.53 338.11 .054 2.14 .6 No comment.

6/5/2001 2.32 .80 259.6 W Rain 3 B 17.50 355.68 .047 .96 .3 No comment.6/12/2001 4.64 1.60 498.0 W Rain 3 B 13.90 565.18 .048 1.94 .3 No comment.6/19/2001 .13 .01 1.7 T Trace rain 0 B -- 0 -- 0 -- No comment.

6/26/2001 12.7 .50 0 W Rain 1 C [16.4] 208.43 [.062] .79 .4 Estimated THg and

MHg deposition.

7/3/2001 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

7/10/2001 39.37 1.55 462.3 W Rain 4 B 19.79 779.36 .067 2.63 .3 No comment.

7/17/2001 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

7/24/2001 8.89 .35 119.3 W Rain 3 B 19.81 176.11 <.021 0 -- MHg not detected.

7/31/2001 8.89 .35 121.2 W Rain 1 B 9.99 88.85 .022 .19 .2 No comment.8/8/2001 8.89 .35 97.3 W Rain 1 B 13.16 117.04 .009 .08 .1 No comment.8/14/2001 11.43 .45 131.4 W Rain 1 B 2.92 239.14 .019 .22 .1 No comment.8/21/2001 29.97 1.18 344.5 W Rain 3 B 13.90 416.88 .030 .90 .2 No comment.8/28/2001 51.05 2.01 652.4 W Rain 4 B 7.64 39.20 .027 1.39 .4 No comment.9/4/2001 3.05 .12 28.0 W Rain 1 B 15.34 46.76 .199 .61 1.3 No comment.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

68  Mercury in Precipitation in Indiana, January 2001–December 2003
9/11/2001 14.48 0.57 151.5 W Rain 3 B 16.78 243.04 0.007 0.11 0 No comment.

9/18/2001 1.16 .40 115.7 W Rain 2 B 2.97 213.05 <.019 0 -- MHg not detected.9/25/2001 33.78 1.33 411.2 W Rain 5 B 9.24 312.31 .037 1.24 .4 No comment.10/2/2001 4.32 .17 59.9 W Rain 3 B 5.37 23.21 .010 .04 .2 No comment.10/9/2001 55.88 2.20 671.9 W Rain 1 B 5.99 334.83 .034 1.89 .6 No comment.10/16/2001 134.62 5.30 1,593.5 W Rain 4 B 11.08 1,491.72 .004 .58 0 No comment.10/23/2001 16.51 .65 183.0 W Rain 1 B 14.19 234.32 .016 .26 .1 No comment.10/30/2001 11.94 .47 136.5 W Rain 1 B 6.46 77.13 .012 .14 .2 No comment.11/6/2001 21.59 .85 27.8 W Rain 1 B 12.91 278.85 .015 .33 .1 No comment.11/13/2001 1.27 .05 16.7 W Rain 1 B 12.70 16.13 <.002 0 -- MHg not detected.11/20/2001 16.38 .64 184.9 W Rain 3 B 1.85 177.78 .004 .06 0 No comment.11/27/2001 12.64 .50 177.9 W Rain 1 B 7.11 89.96 .010 .13 .1 No comment.12/4/2001 18.16 .71 216.2 W Rain 1 B 3.66 66.57 .081 1.48 2.2 No comment.12/11/2001 1.90 .07 16.8 W Rain 1 B 1.81 2.60 .281 .53 2.6 No comment.12/18/2001 2.95 .82 232.9 W Rain 3 B 6.01 126.12 Low vol Low vol -- No comment.12/26/2001 7.80 .31 93.5 W Rain 3 B 5.54 43.23 .108 .84 1.9 Use bottle catch

7.8 mm to computedeposition.

1/2/2002 1.78 .07 (1.0) W Snow 3 C [7.1] 12.65 Low vol Low vol -- Low volume sample;

estimated THgdeposition.

1/8/2002 5.08 .2 45.8 W Snow 2 B 4.97 25.27 .060 .31 1.2 No comment.1/15/2002 .13 .01 4.7 T Trace snow 0 B -- 0 -- 0 -- No comment.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-4  69
1/22/2002 3.05 0.12 35.7 W Mixed 2 B 5.16 15.75 0.071 0.22 1.4 No comment.

1/29/2002 1.27 .05 11.3 W Snow 1 B 8.48 1.78 Low vol Low vol -- No comment.2/5/2002 44.96 1.77 527.6 W Mixed 1 B 3.78 17.07 <.022 0 -- MHg not detected.2/12/2002 .25 .01 2.4 W Snow 1 B 19.42 4.93 Low vol Low vol -- No comment.2/19/2002 4.32 .17 52.2 W Rain 2 B 13.12 56.65 .034 .15 .3 No comment.2/26/2002 21.08 .83 213.0 W Mixed 3 B 6.24 131.57 .073 1.54 1.2 No comment.3/5/2002 3.48 1.20 297.8 W Snow 1 B 5.17 157.70 .032 .98 .6 No comment.3/12/2002 12.70 .50 174.0 W Rain 1 B 17.59 223.41 <.022 0 -- MHg not detected.3/19/2002 .25 .01 .7 T Trace rain 0 B -- 0 -- 0 -- No comment.

3/26/2002 12.19 .48 95.9 W Mixed 4 B 12.36 15.69 .023 .28 .2 No comment.4/2/2002 24.13 .95 282.4 W Mixed 2 B 25.47 614.66 .178 4.29 .7 No comment.4/9/2002 34.54 1.36 0 W Rain 1 C [16.1] 21.91 .037 1.29 5.9 Alternate rain gage

data; estimateddeposition.

4/16/2002 0.25 0.01 0.1 T Trace rain 0 B -- 0 -- 0 -- No comment.

4/23/2002 38.10 1.50 46.1 W Rain 2 B 23.76 905.40 .090 3.45 .4 No comment.4/30/2002 2.32 .80 225.1 W Rain 2 B 8.18 166.35 .098 1.99 1.2 No comment.5/7/2002 9.65 .38 126.5 W Rain 2 B 23.24 224.33 .077 .75 .3 No comment.5/14/2002 108.46 4.27 1,336.7 W Rain 2 B 13.44 1,458.21 .023 2.53 .2 Alternate rain-gage

data used tocomputedeposition.

5/21/2002 12.70 .50 148.5 W Rain 1 B 10.39 132.01 .034 .43 .3 No comment.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

70 Mercury in Precipitation in Indiana, January 2001–December 2003
5/28/2002 17.78 0.70 217.9 W Rain 1 B 8.25 146.68 0.066 1.17 0.8 No comment.

6/4/2002 3.81 .15 56.7 W Rain 1 B 23.88 91.01 .239 .91 1.0 No comment.6/11/2002 3.30 .13 (35.3) W Rain 2 C [16.1] 53.17 .080 .26 .5 Estimated THg

deposition.

6/18/2002 6.35 .25 94.6 W Rain 3 B 18.82 119.51 .008 .05 0 No comment.6/25/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

7/3/2002 46.15 1.82 552.9 W Rain 3 B 15.14 699.08 .117 5.38 .8 Use bottle catch

46.15 mm tocomputedeposition.

7/9/2002 7.11 .28 27.4 W Rain 1 B 33.36 237.3 Low vol Low vol -- No comment.

7/16/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

7/23/2002 3.81 .15 (42.5) W Rain 1 C [14.3] 54.52 [.044] .17 .3 Estimated THg and

MHg deposition.

7/30/2002 15.49 .61 144.4 W Rain 4 B 8.20 127.08 .010 .15 .1 Alternate rain-gage

data used tocomputedeposition.

8/6/2002 7.11 .28 85.3 W Rain 2 B 16.74 119.09 .031 .22 .2 No comment.

8/13/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

8/20/2002 37.85 1.49 (438.3) W Rain 3 C [14.3] 541.66 Low vol Low vol -- Estimated THg

deposition.

8/28/2002 45.21 1.78 543.9 W Rain 2 B 2.77 939.18 .013 .59 .1 No comment.

9/3/2002 4.45 .18 33.9 W Rain 1 B 11.12 49.44 .080 .36 .7 No comment.9/10/2002 0 0 0 D Dry 0 B -- 0 -- 0 -- No comment.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-4  71
9/17/2002 1.27 0.05 12.1 W Rain 1 B 12.31 15.63 0.386 0.49 3.1 No comment.

9/24/2002 43.18 1.70 542.7 W Rain 3 B 7.38 319.05 .005 .20 .1 No comment.10/1/2002 5.84 .23 71.8 W Rain 1 A 35.41 206.91 .034 .20 .1 No comment.10/8/2002 26.67 1.05 309.8 W Rain 2 B 6.39 17.42 .009 .24 .1 No comment.10/15/2002 5.08 .20 62.8 W Rain 1 B 8.34 42.39 .054 .27 .6 No comment.10/22/2002 2.03 .08 33.2 W Rain 2 A 13.25 26.92 .151 .31 1.1 No comment.10/29/2002 5.08 .2 51.2 W Rain 1 B 11.54 58.62 .086 .44 .7 No comment.11/5/2002 .51 .02 5.4 W Rain 2 B 1.54 .78 Low vol Low vol -- No comment.11/12/2002 25.91 1.02 307.4 W Rain 2 B 8.88 23.08 .035 .91 .4 No comment.11/19/2002 7.37 .29 88.3 W Rain 3 B 4.83 35.61 .116 .85 2.4 Use bottle catch

7.37 mm tocomputedeposition.

11/26/2002 9.40 .37 91.3 W Mixed 2 B 5.54 52.12 .117 1.10 2.1 No comment.12/3/2002 4.83 .19 53.2 W Snow 3 B 7.24 34.95 .053 .26 .7 No comment.12/10/2002 0.13 0.01 0.3 T Trace snow 0 B -- 0 -- 0 -- No comment.

12/17/2002 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.

12/24/2002 35.56 1.4 416.3 W Rain 1 B 13.59 483.29 .030 1.07 .2 No comment.

12/31/2002 11.94 .47 109.5 W Snow 1 A 3.28 39.16 .028 .34 .9 No comment.1/7/2003 3.81 .15 2.7 W Snow 2 A 4.97 156.09 <.002 0 -- MHg not detected.1/14/2003 2.54 .10 27.4 W Snow 1 A 5.61 14.26 <.002 0 -- MHg not detected.1/21/2003 16.51 .65 141.5 W Snow 1 A 5.05 83.49 .0520 .86 1.0 No comment.1/28/2003 4.57 .18 2.5 W Snow 3 A 1.54 48.20 .266 1.22 2.5 No comment.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

72 Mercury in Precipitation in Indiana, January 2001–December 2003
2/4/2003 13.97 0.55 149.6 W Snow 3 B 6.76 94.50 Low vol Low vol -- No comment.

2/11/2003 1.02 .04 [1.4] W Snow 2 C [12.2] 12.45 Low vol Low vol -- Low volume sample;

estimateddeposition.

2/18/2003 2.03 .08 18.5 W Snow 1 A 2.03 4.71 0.040 0.08 0.2 No comment.2/25/2003 1.27 .05 4.6 W Snow 1 B 8.64 1.97 Low vol Low vol -- No comment.3/4/2003 1.78 .07 11.4 W Snow 2 A 1.56 18.79 Low vol Low vol -- No comment.3/11/2003 16.51 .65 159.8 W Snow 2 B 12.21 201.62 .085 1.34 .7 No comment.3/18/2003 3.81 .15 44.7 W Rain 1 B 35.53 135.38 Low vol Low vol -- No comment.

3/25/2003 8.89 .35 117.0 W Rain 3 B 22.98 204.32 Low vol Low vol -- No comment.4/1/2003 4.57 .18 70.0 W Rain 4 A 13.98 63.91 .270 1.23 1.9 No comment.4/8/2003 56.39 2.22 672.0 W Rain 3 B 11.76 663.63 .031 1.77 .3 No comment.4/15/2003 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

4/22/2003 11.43 .45 151.7 W Rain 3 B 15.30 174.98 .118 1.35 .8 No comment.

4/28/2003 0 0 0 D QC 0 B <.05 0 -- 0 -- Field bottle blank;

no Hg detected.

5/6/2003 66.80 2.63 735.3 W Rain 3 B 15.42 103.08 .064 4.31 .4 No comment.5/13/2003 64.26 2.53 829.6 W Rain 4 B 16.87 1,084.29 .101 6.48 .6 No comment.5/20/2003 13.46 .53 165.4 W Rain 2 B 16.91 227.69 .080 1.08 .5 No comment.5/27/2003 .25 .01 2.7 W Rain 1 B 37.60 9.55 Low vol Low vol -- No comment.6/3/2003 36.83 1.45 43.9 W Rain 3 B 19.00 70.10 .364 13.41 1.9 No comment.6/10/2003 5.33 .21 7.4 W Rain 2 B 47.48 253.29 1.137 6.06 2.4 No comment.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-4  73
6/18/2003 8.13 0.32 92.6 W Rain 1 B 17.00 138.21 0.077 0.63 0.5 No comment.

6/24/2003 17.78 .70 195.9 W Rain 1 B 11.20 199.24 .114 2.02 1.0 No comment.7/1/2003 2.07 .79 (13.3) W Rain 2 C [16.8] 337.43 [.281] 5.64 1.7 Alternate rain-gage

data; estimatedTHg and MHgdeposition.

7/9/2003 55.12 2.17 721.7 W Rain 4 B 18.22 1,004.58 .059 3.27 .3 No comment.7/15/2003 19.56 .77 213.1 W Rain 2 B 27.10 53.1 .135 2.65 .5 No comment.7/22/2003 74.68 2.94 905.9 W Rain 2 A 17.31 1,293.09 .119 8.88 .7 No comment.7/29/2003 38.10 1.50 457.4 W Rain 1 B 1.54 401.76 1.352 51.56 12.8 Largest MHg

concentration andMHg depositionand MHg/THgratio in 3 years,2001–2003.

8/5/2003 12.70 .50 139.8 W Rain 3 B 29.29 371.98 .047 .6 .2 Alternate rain gage

data used to computedeposition

8/12/2003 1.02 .04 11.7 W Rain 1 A 28.02 28.47 Low vol Low vol -- No comment.

8/19/2003 0 0 0 D Dry 0 A -- 0 -- 0 -- No comment.

8/26/2003 .13 .01 1.8 T Trace rain 0 B -- 0 -- 0 -- No comment.

9/2/2003 56.39 2.22 68.3 W Rain 2 B 12.7 716.12 .149 8.39 1.2 No comment.9/9/2003 0 0 0 D Dry 0 B 0 0 -- No comment.

9/16/2003 7.87 .31 0 W Rain 1 C [16.8] 132.31 Low vol Low vol -- Low volume sample;

estimateddeposition.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2

)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2

)

Ratio

methylmercury

to total

mercury

(percent)

Comments

74  Mercury in Precipitation in Indiana, January 2001–December 2003
9/23/2003 12.45 0.49 143.1 W Rain 1 A 18.34 228.32 0.092 1.14 0.5 No comment.

9/30/2003 18.29 .72 (192.1) W Rain 3 C [1.9] 199.51 [.054] .99 .5 Estimated THg and

MHg deposition.

10/7/2003 5.33 .21 62.0 W Rain 1 A 6.71 35.83 .099 .53 1.5 No comment.

10/14/2003 2.57 .81 406.5 W Rain 2 C 12.27 252.56 .070 1.45 .6 Sampler lid cycled

briefly on 4 daysverified as dry; usefor summary.

10/21/2003 24.64 .97 87.6 W Rain 1 A 4.78 117.77 .102 2.5 2.1 No comment.

10/28/2003 17.53 .69 20.6 W Rain 2 B 23.64 414.45 .130 2.28 .5 No comment.11/4/2003 34.04 1.34 432.0 W Rain 3 B 12.81 436.27 .029 1.00 .2 No comment.

11/12/2003 2.32 .80 24.1 W Rain 2 B 14.28 29.31 .032 .66 .2 No comment.11/18/2003 19.56 .77 21.1 W Rain 2 A 16.39 32.71 .005 .10 0 No comment.11/25/2003 35.81 1.41 463.8 W Rain 2 B 4.26 152.74 .029 1.05 .7 No comment.12/2/2003 .25 .01 3.8 W Snow 1 B 15.01 3.81 Low vol Low vol -- Low volume sample.12/9/2003 14.99 .59 206.6 W Mixed 1 A 4.91 73.64 .103 1.54 2.1 No comment.12/16/2003 15.24 .60 187.5 W Mixed 1 A 6.24 95.23 .061 .93 1.0 No comment.12/23/2003 3.56 .14 12.5 W Mixed 3 A 11.90 42.32 .028 .10 .2 No comment.12/30/2003 5.84 .23 52.0 W Snow 2 A 12.18 71.17 Low vol Low vol -- No comment.

Appendix 1-4. Weekly precipitation, total mercury, and methylmercury at Indiana Dunes monitoring station near Porter, Indiana, January 2001–December 2003.—Continued[mm, millimeter; in., inch; mL, milliliter; ng/L, nanogram per liter; ng/m2, nanogram per square meter; W, wet deposition; D, Dry sample; T, trace sample; QC, quality-control sample; parentheses, sample

volume not included in volume-weighted concentration; brackets, volume-weighted concentration for estimated deposition; Low vol, Low volume insufficient for methylmercury analysis; <, less than detection limit listed; --, no analysis; NTN, National Trends Network; Hg, mercury; MHg, methylmercury; THg, total mercury; significant digits in this table are consistent with raw data from National Atmospheric Deposition Program Mercury Deposition Network on-line data archive] 

Date 

sample

 removed

Precipitation

(mm)

Precipitation

(in.)

Sample

volume 

(mL)

Sample

type

Precipitation

type

Wetdeposition

events

Dataquality

 rating

 Total

mercuryconcentration

(ng/L)

Total

mercury

deposition

(ng/m2)

Methylmercury

concentration

 (ng/L)

Methylmercury

deposition

(ng/m2)

Ratio

methylmercury

to total

mercury

(percent)

Comments

Appendix 1-4  75
76  Mercury in Precipitation in Indiana, January 2001–December 2003 Appendix 2-1. Summary of laboratory quality-control sample data for analysis of total mercury concentrations, January 2001–December 2003. [std.dev., standard deviation; ng, nanogram] Calibration standards correlation coefficient Standard reference material percent recovery Duplicate sample relative percent difference Matrix-spike / matrix-spike duplicate percent recovery Laboratory bottle blank mercury concentration (ng/bottle) Year Quarter Mean Std. dev. Samples Mean Std. dev. Samples Mean Std. dev. Samples Mean Std. dev. Samples Mean Std. dev. Samples 2001 1st 0.99787 0.00598 25 99.1 8.7 74 5.6 6.1 74 95.0 17.3 74 0.018 0.019 10 2nd .99886 .00116 27 97.3 7.2 78 4.5 5.5 78 101.2 14.3 78 .015 .007 13 3rd .99892 .00123 26 91.1 3.0 75 5.2 6.0 75 100.0 14.7 75 .054 .065 9 4th .99929 .00077 35 93.3 3.4 50 5.7 6.3 100 101.6 11.7 100 .048 .033 22 2002 1st .99930 .00055 28 93.6 4.2 81 5.6 6.2 91 98.7 9.1 81 .028 .011 10 2nd .99890 .00131 20 93.6 9.2 66 5.8 4.8 60 98.8 8.9 60 .034 .018 21 3rd .99960 .00034 31 94.0 3.2 93 3.3 3.5 93 99.2 5.2 93 .085 .096 14 4th .99979 .00017 37 88.9 2.2 78 4.0 4.1 108 101.1 4.8 108 .063 .071 21

2003 1st .99860 .00696 28 98.2 2.6 56 4.0 7.8 84 99.4 10.3 84 .057 .162 23

2nd .99974 .00031 35 95.8 2.6 70 2.4 6.7 105 97.1 10.5 105 .025 .015 183rd .99961 .00045 38 94.4 3.7 56 3.9 3.7 113 101.2 10.6 109 .030 .022 274th .99973 .00028 37 95.0 2.8 74 4.0 6.1 111 99.0 14.4 110 .020 .007 15

Martin R. Risch—Mercury in Precipitation in Indiana, January 2001–December 2003—Scientific Investigations Report 2007-5063