Sando and others—Mercury and Methylmercury in Water and Bottom Sediments, Lostwood National Wildlife Refuge—Scientific Investigations Report 2007–5219

Prepared in cooperation with the North Dakota Department of Health

Mercury and Methylmercury in Water and Bottom Sediments 

of Wetlands at Lostwood National Wildlife Refuge, North 

Dakota, 2003–04

LOSTWOOD

NATIONAL

WILDLIFE

REFUGE

Fargo

BISMARCK

BURKE

MOUNTRAIL

N O R T H D A K O T A

C A N A D A

U N I T E D S T A T E S Lake Devils

RED RIVE

MISSOURI

RIVER River

Souris

BURKE CO.

MOUNTRAIL CO.

Docs

Lake

Iverson

Lake

Solon

Lake

Elbow

Lake

Rush

Lake

Iverson

Slough

Tower

Slough

Jerrys

Slough

Kittelson

Slough

Rock

Slough

Knudson

Slough

Ruddy

Slough

Upper

Thompson

Lake

Thompson Lake

Upper Lostwood

 Lake

Lower

Lostwood

Lake

School

Section

Lake

4

6

5

1

2

10

15

20 19

22

26 27

23

24

17

33

34 35

39

40

41

42

44

43

37 38 36

30

29

32

25

28

31

18

16

21

9

7

8

3

11

12 13

14

Scientific Investigations Report 2007–5219

U.S. Department of the Interior

U.S. Geological Survey Printed on recycled paper
Mercury and Methylmercury in Water and 

Bottom Sediments of Wetlands at Lostwood National Wildlife Refuge, North Dakota, 2003–04By Steven K. Sando, D.P. Krabbenhoft, Kevin M. Johnson, Robert F. Lundgren, and 

Douglas G. Emerson
U.S. Department of the Interior

DIRK KEMPTHORNE, SecretaryU.S. Geological SurveyMark D. Myers, DirectorU.S. Geological Survey, Reston, Virginia: 2007For product and ordering information:World Wide Web: http://www.usgs.gov/pubprod

Telephone: 1-888-ASK-USGSFor more information on the USGS—the Federal source for science about the Earth,its natural and living resources, natural hazards, and the environment:World Wide Web: http://www

usgs

gov
 iii

ContentsAbstract. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Description of Study Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Wetland Sampling Site Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Collection, Processing, and Analysis of Water and Bottom-Sediment Samples. . . . . . . . . . . . . . . . . . . . . . . . . 7Collection, Processing, and Analysis of Quality-Assurance/Quality-Control Samples . . . . . . . . . . . . . . . . . . 10

Climatic Conditions Prior to Sample Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Mercury and Methylmercury in Water and Bottom Sediments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Wetland Water and Bottom-Sediment Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Patterns in Occurrence of Mercury, Methylmercury, and Other Water-Quality

Properties and Constituents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Mercury Constituents in Water and Bottom-Sediment Samples and Properties

of Bottom-Sediment Samples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Water-Quality Properties and Constituents Measured at Time of Sample

Collection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Major-Ion and Selected Trace-Element Constituents in Water Samples. . . . . . . . . . . . . . . . . . . . . . . . . 20O

i

C

b

C

i

i

W

S

l

2
iv 

Figures, Continued

3. Aerial photographs showing differences in wetland inundation between 2003

and 2004 for the northern part of Lostwood National Wildlife Refuge, North Dakota. . . . . . . . . . . . . . . . 13

4. Box plots showing concentrations of selected mercury constituents in water

samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

5. Box plots showing concentrations of selected mercury constituents in bottomsediment samples and percent loss on ignition for bottom-sediment samples. . . . . . . . . . . . . . . . . . . . . .166. Box plots showing water-quality property and constituent values measured

at time of sample collection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

7. Box plots showing concentrations of dissolved solids and dissolved

sulfate in water samples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

8. Box plots showing concentrations and proportions of major ions for wetlands

sampled in both 2003 and 2004. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

9. Box plots showing concentrations of selected nonmercury trace elements

in water samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

10. Box plots showing concentrations of organic-carbon constituents in water

samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

11. Graphs showing relations between dissolved solids, dissolved organic carbon,

selected mercury constituents, and pH in the Lostwood National Wildlife Refugewetlands for 2003 and 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

12. Graphs showing relations between whole-water total mercury and dissolved

organic carbon in the Lostwood National Wildlife Refuge wetlands for 2003
 v

Conversion Factors and Datum

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)inch (in.) 25.4 millimeter (mm)foot (ft) 0.3048 meter (m)mile (mi) 1.609 kilometer (km)

Area

acre 4,047 square meter (m2)acre 0.4047 hectare (ha)acre 0.4047 square hectometer (hm2)acre 0.004047 square kilometer (km2)

Flow rate

mile per hour (mi/h) 1.609 kilometer per hour (km/h)

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows:°F = (1.8 x °C) + 32Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows:°C = (°F-32)/1.8Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83)
vi 
Mercury and Methylmercury in Water and Bottom 

Sediments of Wetlands at Lostwood National Wildlife Refuge, North Dakota, 2003–04

By Steven K. Sando, D.P. Krabbenhoft, Kevin M. Johnson, Robert F. Lundgren, and Douglas G. EmersonAbstract

Certain ecosystem types, particularly wetlands, have

environmental characteristics that can make them particularly sensitive to mercury inputs and that can result in large mercury concentrations in fish or other aquatic biota. To provide information needed to make effective management decisions to decrease human and wildlife exposure to methylmercury in northern prairie pothole wetlands, the U.S. Geological Survey, in cooperation with the North Dakota Department of Health, conducted a study to assess mercury and methylmercury con

2001). Scientific attention to the occurrence of Hg in aquatic systems has been motivated largely by concerns about effects on human health. However, aquatic food webs might be

particularly vulnerable to Hg because, unlike humans, aquatic organisms cannot modify their diet in response to advisories. Widespread Hg in aquatic food webs generally is a result of anthropogenic Hg emissions (primarily from coal combustors and waste incinerators) and long-range atmospheric transport (Fitzgerald and Watras, 1989). Thus, almost all aquatic ecosystems are potentially susceptible to Hg contamination. The seemingly incongruent relation between a diffuse, low-level source of Hg (atmospheric Hg deposition) and large Hg concen
48 ̊40' 48 ̊40'

102 ̊30'

102 ̊30'

102 ̊25'

14 13 18 17 16 15

7 8 9 106 5 4 3

31 32 33 34

30 29 28 27

21 22

3526

19 20 23

11 12

R. 92 W. R. 91 W.

T. 160 N.T. 159 N.

T. 160 N.T. 159 N.

Docs

Lake

Iverson

Lake

Solon

Lake

Elbow

Lake

Iverson

Slough

Teal

Slough

Goose Pan

Slough

Tower

Slough

Jerrys

Slough

Pauls

Slough

Merrills

Slough

Niels

Slough

Dead Dog

Slough

Hidden

Slough

Sectionline

Slough

Ruddy

Slough

Upper

Thompson

Lake

School

Section

Lake

Thompson

Lake

2 4 5 1 6

10

15

20 19

22

26 27

23

24

17

33

35 34

30

29

32

25

28

31

18

16

21

9

7 8 3

11

13 12

14

SOUTH DAKOTA

MONTANA

MINNESOTA

SASKATCHEWAN MANITOBA

Fargo BISMARCK

Estevan

Lake Devils

RED RIVER OF THE NORTH MISSOURI

RIVER

River

BURKE

Souris

MOUNTRAIL

101 ̊ 99 ̊

103 ̊ 101 ̊ 99 ̊

47 ̊ 47 ̊

97 ̊

49 ̊ 49 ̊

STUDYAREA

INDEX MAP

2 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
Description of Study Area 3

tions are similar to those in the Florida Everglades, where large MeHg concentrations in fish have been documented (Krabbenhoft, 1996). Although concentrations in the two samples indicate prairie pothole wetlands at the Refuge are Hg sensitive and efficiently transform inorganic Hg into the much more toxic MeHg, the level of bioaccumulation that is occurring, the range in MeHg concentrations among seasons, and whether the range in physical, hydrological, and chemical characteristics of the wetlands affects MeHg production are unknown.

The many tens of thousands of prairie pothole wetlands 

that exist across the northern high plains serve as a critical 

aquatic ecosystem for native and migratory wildlife in North America (Batt and others, 1989; Swanson and Duebbert, 1989). However, little information currently (2007) is available on Hg cycling, fate, and biological exposure in the wetlands. Therefore, because environmental managers and scientists need to 

make effective management decisions to decrease human and wildlife exposure to MeHg, the environments that are most prone to MeHg production need to be better defined and the limiting factors for MeHg production for each ecosystem type need to be established. To provide managers and scientists with the information needed to make effective decisions, the U.S. 

Geological Survey, in cooperation with the North Dakota Department of Health, conducted a study to assess Hg and MeHg concentrations in prairie pothole wetlands. The purpose of this report is to describe Hg and MeHg in water and bottom sediments of wetlands at the Refuge in 2003–04. The report

needlegrass, wheatgrass, grama grass, and plains muhly.

Prescribed burning and grazing are the primary management tools used on the Refuge.

The Refuge contains a 5,577-acre Wilderness Area with 

designated Class I air quality and is listed as a Globally Important Bird Area (American Bird Conservancy, 2007). Birding is 

an important public use, and avian species make up the largest and most diverse faunal group on the Refuge. Shorebirds, waterfowl, raptors, and passerines use various habitats on the Refuge during migration, and the federally threatened piping plover uses shoreline habitats on the large alkali wetlands for breeding each year.

Surface runoff and subsurface seepage from rainfall and 

snowmelt on the Refuge results in wetlands that have a large range in size, hydrologic conditions, and water quality. Variability in climate, soils, topography, geology, and hydrology 

results in substantial variability in water regimes of the wetlands. The U.S. Fish and Wildlife Service (2006) used methods described by Stewart and Kantrud (1971) and Cowardin and others (1979) to classify the wetlands at the Refuge by water regime. Results of that classification were used in this study to classify each wetland sampled in the study. The wetlands were classified on the basis of water regime as one of four major types—temporary, seasonal, semipermanent, and lake. An individual wetland might actually have characteristics of more than one water regime; however, for this study, the water regime that accounted for the largest part of the total wetland area was 
Table 1. General qualitative characteristics of wetland types.

Wetland

type

General

geomorphology

characteristics

General patterns in

ground-water/

surface-water

relations

Frequency and

duration of

inundation

Predominant

vegetation

regime

Temporary Small in surface

area andshallow

Movement of water is from

wetland into local groundwater throughout

Inundated for brief periods

during the growingseason in most years

Dense growth of grasses

and sedges throughoutthe wetland bottom

Seasonal Relatively small

in surface areaand shallow

Movement of water is from

wetland into local groundwater throughout

Inundated for extended

periods, especially earlyin the growing season,in most years

Dense growth of grasses,

sedges, cattails, and/orbulrushes throughout thewetland bottom

Semipermanent Moderately large

in surface areaand moderatelydeep

Areas where movement of

water is from wetland intolocal ground water and alsoareas where movement ofwater is from local groundwater into wetland

Inundated throughout the

growing season in mostyears and year-round insome years

Sparse growth of submergent

vegetation in open-waterareas; fringed with densegrowth of cattails andbulrushes

Lake Large in surface

area and deep

Areas where movement of

water is from wetland intolocal ground water but

Inundated year-round in

nearly all years

Sparse to dense growth of

submergent vegetation (sagopondweed and/or widgeon

4 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
Methods 5

MethodsWetland Sampling Site Selection

A stratified randomization scheme was used to select

wetland sampling sites for 2003. Initially, six wetlands within each of the four major wetland types were randomly selected for sampling to provide equal representation among the types and to provide a basis for statistical comparisons among the types. However, after the wetlands were sampled in April 2003, a determination was made that three of the wetlands that had been classified as semipermanent wetlands should have been classified as seasonal wetlands. Although the ability to make statistical comparisons was reduced because of the change, patterns of differences in water quality among the wetland types still were discernible. The 24 wetlands sampled in April 2003 consisted of 6 temporary wetlands, 9 seasonal wetlands, 3 semipermanent wetlands, and 6 lake wetlands.

In 2004, dry climatic conditions limited the ability to

randomly select wetlands for sampling. Thus, a nonrandomized scheme was developed to select wetland sampling sites for 2004. The 25 wetlands sampled in 2004 consisted of 5 previously sampled wetlands (1 temporary wetland, 1 seasonal wetland, 1 semipermanent wetland, and 2 lake wetlands) and 20 

previously unsampled wetlands (2 temporary wetlands, 9 seasonal wetlands, 7 semipermanent wetlands, and 2 lake wetlands). The five previously sampled wetlands were selected to be resampled in 2004 to provide information on interannual variability in water quality. Preliminary examination of the 2003 results indicated seasonal and semipermanent wetlands generally tended to have larger MeHg concentrations than temporary and lake wetlands (as discussed in more detail in subsequent sections of this report); therefore, seasonal and semipermanent wetlands were sampled more frequently than the other wetlands in 2004 to possibly obtain further information on Hg methylation. Also, few temporary wetlands contained adequate water for sampling in 2004.

A naming convention for individual wetland sampling 

sites was developed on the basis of wetland type, an arbitrary 

wetland identification number, the management unit containing the wetland, and the year the wetland first was sampled. Alpha codes for wetland types and management units used in the

naming convention are given in table 2. For example, sampling site SS4WLD04 is seasonal wetland (SS) number 4 (4) in the Wilderness (WLD) management unit and first was sampled in 2004 (04). Water and bottom-sediment samples were collected at 44 sampling sites (table 3, fig. 1) at the Refuge in 2003 and 2004.
6 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

Table 3. Wetland sampling sites.

Sampling

site number

(see

figure 1)

Sampling

site name

U.S. Geological Survey

identification

number

Latitude Longitude Surface area (acres) Years sampled

1 SS4WLD04 484033102261900 48°40'33" 102°26'19" 0.54 20042 SM4WLD04 484033102254900 48°40'33" 102°25'49" .95 20043 SM1THL04 484033102241500 48°40'33" 102°24'15" 2.38 20044 SS1THL03 484031102240000 48°40'31" 102°24'00" 1.37 20035 SM3WLD04 484029102265500 48°40'29" 102°26'55" 1.79 20046 SS1WLD03 484025102281800 48°40'25" 102°28'18" .17 20037 TP2WLD04 484024102270600 48°40'24" 102°27'06" .09 20048 SM2WLD04 484020102270700 48°40'20" 102°27'07" 3.13 20049 TP1WLD03 484007102291300 48°40'07" 102°29'13" .17 2003

10 SM1WLD03 483958102283400 48°39'58" 102°28'34" 3.98 200311 TP1THL03 484002102235000 48°40'02" 102°23'50" .19 200312 LK1THL03 483859102240400 48°38'59" 102°24'04" 320.08 2003, 200413 SS1TLS04 483915102252200 48°39'15" 102°25'22" 2.48 200414 SS1TWS04 483901102250600 48°39'01" 102°25'06" .78 200415 SS2WLD04 483808102290100 48°38'08" 102°29'01" 1.26 2004
Methods 7

Collection, Processing, and Analysis of Waterand Bottom-Sediment Samples

were collected using the hand grab method from about middepth in the water column. Sample bottles were rinsed three times with wetland water before final filling

Field crews wore 

36 LK1WWH03 483415102261400 48°34'15" 102°26'14" 534.75 200337 SS3KRU04 483457102280600 48°34'57" 102°28'06" .60 200438 SS1KRU03 483456102275600 48°34'56" 102°27'56" 1.45 2003, 200439 SS2KRU03 483453102273500 48°34'53" 102°27'35" .63 200340 LK1KRU03 483354102265300 48°33'54" 102°26'53" 34.07 2003, 200441 TP1WSU03 483339102261600 48°33'39" 102°26'16" .22 200342 SM1WLL04 483330102261700 48°33'30" 102°26'17" 12.65 200443 LK1ELS04 483223102271400 48°32'23" 102°27'14" 437.52 200444 SS1ELN03 483229102250400 48°32'29" 102°25'04" .29 2003

Table 3. Wetland sampling sites.—Continued

Sampling

site number

(see

figure 1)

Sampling

site name

U.S. Geological Survey

identification

number

Latitude Longitude Surface area (acres) Years sampled
8 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

Table 4. Properties and constituents for which water samples and bottom-sediment samples were analyzed.

Property or constituent Study reporting level and units

Field measurements

Depth to bottom from water surface at sampling site location 0.1 foot1Barometric pressure 1 millimeter mercury1Specific conductance 5 microsiemens per centimeter1pH 0.1 standard unit1Air temperature 0.1 degree Celsius1Water temperature 0.1 degree Celsius1Turbidity 1 formazin nephelometric unit1Dissolved oxygen 0.1 milligram per liter1

Laboratory analyses

Major ions, suspended solids, and selected trace elements

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

Hardness, total 1 milligram per liter as calcium carbonate2Calcium, dissolved 2 milligrams per liter3Magnesium, dissolved 1 milligram per liter3Sodium, dissolved 3 milligrams per liter3Percent sodium, in equivalents of major cations 1 percent2S

di

d

i

i

0

12
Methods 9

Mercury and organic carbon

(U.S.Geological Survey Wisconsin Water Science Center Mercury Laboratory, Madison, Wisconsin)

Methylmercury, water, dissolved 0.04 nanogram per liter4Methylmercury, water, suspended 0.03 nanogram per liter5Methylmercury, water, whole-water 0.04 nanogram per liter2Total mercury, water, dissolved 0.1 nanogram per liter6Total mercury, water, suspended 0.1 nanogram per liter7Total mercury, water, whole-water 0.1 nanogram per liter2Organic carbon, water, dissolved 0.01 milligram per liter8Organic carbon, water, whole-water 0.1 milligram per liter8Methylmercury, bottom sediment (methylmercury, solid, total, dry weight) 0.4 nanogram per gram5Total mercury, bottom sediment (mercury, solid, total, dry weight) 0.01 nanogram per gram7Loss on ignition, bottom sediment (loss on ignition, solids) 1 percent9

1Wilde and others, 1998.2Calculated.3North Dakota Department of Health, 2003a, 2003b.4DeWild and others, 2002.

Table 4. Properties and constituents for which water samples and bottom-sediment samples were analyzed.—Continued

Property or constituent Study reporting level and units
10 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

all organic Hg present in the water samples was assumed to be monomethylmercury because dimethylmercury is exceedingly rare and has been detected only in marine settings. Inorganic Hg concentrations in water samples were calculated by subtracting MeHg concentrations from total Hg (THg) concentrations. In this calculation, if either the MeHg or THg concentration for a given sample was less than the study reporting level (table 4), the concentration for the less-than fraction was assumed to be zero. To determine dissolved concentrations of Hg and organiccarbon constituents, water samples were passed through ultraclean, 0.7-micrometer-nominal-pore size, quartz-fiber filters in 

the processing area at the Refuge headquarters. Thus, in this report, the term dissolved with respect to Hg and organiccarbon constituents is operationally defined as that part of a 

water sample that passes through a 0.7-micrometer filter, noting that some fraction of the dissolved part is composed of filterpassing colloids. To determine suspended concentrations of Hg constituents, known volumes of sample water were passed through ultra-clean, 0.7-micrometer-nominal-pore-size, quartzfiber filters. The filter and retained suspended material were digested and the resulting solution was analyzed using methods described by Olund and others (2004) for Hg and by DeWild and others (2004) for MeHg. Mass/volume suspended concentrations of Hg constituents then were determined on the basis of the original known volume of sample water that was filtered. To determine whole-water concentrations of Hg constituents, dis

Climatic Conditions Prior to Sample Collection

Climatic conditions prior to sample collection in 2003 and 

2004 (table 5, fig. 2) differed substantially and likely affected 

the results obtained during this study. Effects of the differences on wetland inundation in the northern part of the Refuge in the springs of 2003 and 2004 are shown in figure 3. For the area of the Refuge (fig. 3), the number of inundated wetlands in 2004 was about 30 percent smaller than the number in 2003 and the total wetted surface area in 2004 was about 35 percent smaller than the total in 2003. These data indicate substantially less runoff of meltwater to the wetlands in 2004 than in 2003. Thelargest decreases between 2003 and 2004 in both the number of inundated wetlands and the total wetted surface area occurred for temporary, seasonal, and semipermanent wetlands. In the prairie pothole region, in years with little winter snowpack and dry antecedent moisture conditions, contribution of water to wetlands generally is from melting snow and ice on the wetland water surface or within the localized wetland depression, and the amount of runoff from surrounding terrestrial areas with associated flushing of soils is small (Waiser and Robarts, 2004).

The climatic data collected at a National Weather Service 

station located at Kenmare, North Dakota (about 15 miles northeast of the Refuge; fig. 3), are presented to provide additional information on climatic conditions at the Refuge during 
Table 5. Climatic conditions at Kenmare, North Dakota (located about 15 miles northeast of Lostwood National Wildlife Refuge), prior to 

sample collection in 2003 and 2004.

Time period

Mean daily air temperature

(degrees Fahrenheit)

Exceedance percentile

1

 of

mean daily air temperature

for specified time period

(based on comparison

with 1971–2000 data)

Total precipitation

(inches)

Exceedance percentile

1

 of

total precipitation for

specified time period

(based on comparison

with 1971–2000 data)

Climatic conditions

prior to samplecollection in 2003

May 1, 2002, to April 30, 2003June 1, 2002, to October 31, 2002November 1, 2002, to April 30, 2003February 1, 2003, to April 30, 2003

38.958.321.123.0

60605480

18.811.2

6.23.5

32372223

Climatic conditions

prior to samplecollection in 2004

May 1, 2003, to April 30, 2004June 1, 2003, to October 31, 2003November 1, 2003, to April 30, 2004February 1, 2004, to April 30, 2004

40.061.120.028.0

46

6

6446

16.8

8.06.11.4

54772283

Mercury and Methylmercury in Water and Bottom Sediments 11

1Exceedance percentile indicates the percentage of time the specified value is equaled or exceeded on average.
Approximate time of

sample collection in 2004

10

9

8

7

654321

Precipitation, in inches

100

9080706050403020

-20

10

-10

Temperature, in degrees Fahrenheit

0

Approximate time ofsample collection in 2003

12 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
June 13, 2003

48 ̊40'

R. 91 W. 102 ̊25'

T. 160 N.

Iverson Iverson

Lake

Iverson Iverson

Slough

Iverson Iverson

Lake

Iverson Iverson

Slough

R. 91 W. 102 ̊25'

LOSTWOOD LOSTWOOD

NATIONAL NATIONAL

WILDLIFE WILDLIFE

REFUGE 

N

SOUTH DAKOTA

NORTH DAKOTA

MONTANA

SASKATCHEWAN MANITOBA

BISMARCK

MISSOURI

RIVER

River

BURKE Souris

MOUNTRAIL

103 ̊ 101 ̊

103 ̊ 101 ̊

47 ̊

49 ̊

STUDYAREA

Mercury and Methylmercury in Water and Bottom Sediments 13
14 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

Patterns in Occurrence of Mercury, Methylmercury, and Other Water-Quality Properties and ConstituentsMercury Constituents in Water and Bottom-Sediment 

Samples and Properties of Bottom-Sediment Samples

Most MeHg, inorganic mercury, and THg in the Refuge 

wetlands was dissolved (supplement 4). Three-fourths of the water samples collected had dissolved fractions of both MeHg and THg that accounted for about 70 percent or more of the whole-water concentrations of those constituents. Hg in the

dissolved state commonly is predominant in surface waters that contain appreciable amounts of dissolved organic carbon (DOC), which is the dominant complexing agent for Hg and MeHg in most natural waters (Krabbenhoft and others, 1999; Wiener and others, 2003). Because MeHg, inorganic mercury, and THg were predominantly dissolved, dissolved and wholewater concentrations of those constituents showed similar patterns among wetland types and between years (supplement 4). Thus, although analytical results are presented for dissolved, suspended, and whole-water concentrations of MeHg, inorganic mercury, and THg, discussion summarizing differences among wetland types and between years generally is limited to whole-water concentrations that are predominantly in the dissolved state. Statistical summaries of concentrations of selected Hg constituents in water and bottom-sediment samples and per

were substantially larger in 2003 than in 2004. Hg can be extensively processed in natural aquatic systems, and all data needed 

to assess in detail various factors that might have affected differences in MeHg concentrations between years were not collected during this study. However, differences in MeHg concentrations in the wetlands between 2003 and 2004 might be attributable to one or more of several factors, including (1) substantial differences in contributions of inorganic Hg and organic carbon (the processing of which is critical to Hg methylation) to the wetlands between years; (2) substantial differences in water chemistry of the wetlands between years that affected the processing of Hg and, thus, the fate and concentrations of different 

forms of Hg in the wetlands; and (3) differences in both contributions of inorganic Hg/organic carbon and water chemistry 

between years that affected the production of MeHg in the wetlands between years.

Whole-water inorganic Hg concentrations ranged from 

0.61 ng/L for site 3 (SM1THL04) for 2004 to 11.7 ng/L for site 42 (SM1WLL04) for 2004 (supplement 4). Most whole-water inorganic Hg concentrations (the middle 80 percent) were between 1.35 and 7.79 ng/L (fig. 4). Generally, inorganic Hg concentrations in the Refuge wetlands were within ranges reported for natural aquatic systems (Krabbenhoft and others, 1999; Wiener and others, 2003). For 2003, the median wholewater inorganic Hg concentration for lake wetlands (1.41 ng/L) was less than that for temporary wetlands (3.82 ng/L) which was less than that for seasonal wetlands (5.47 ng/L) which was 
2003 2004

(6) (8) (3) (6) (3) (10) (8) (4)(6) (8) (3) (6) (3) (10) (8) (4)

2003 2004

(6) (9) (3) (6) (3) (10) (8) (4)(6) (9) (3) (6) (3) (10) (8) (4)

mercury, in nanograms per liter

0.01

0.1

1

10

100

1

10

100

Whole-water methylmercury, in nanograms per liter 0.01 0.1

1

10

100

Whole-water total mercury, in nanograms per liter

0.50.60.70.80.9

1

water methylmercury

ater total mercury

Wetland type

TP SS SM LK TP SS SM LK TP SS SM LK TP SS SM LK

Wetland type

Wetland type Wetland type

Mercury and Methylmercury in Water and Bottom Sediments 15
2003 2004

(6) (8) (3) (6) (3) (10) (8) (4)

2003 2004

0.1

1

10

(6) (9) (3) (6) (3) (10) (8) (4)

(6) (9) (3) (6) (3) (10) (8) (4)

0

0.010.020.030.040.050.060.070.080.09

0.1

Ratio of methylmercury to total mercury

5060708090

100

or bottom-sediment samples

(6) (9) (3) (6) (3) (10) (8) (4)

10

100

nanograms per gram Methylmercury, in nanograms per gram

Wetland type Wetland type

Wetland type Wetland type

TP SS SM LK TP SS SM LK TP SS SM LK TP SS SM LK

16 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
Mercury and Methylmercury in Water and Bottom Sediments 17

than in 2003, possibly indicating that less inorganic Hg was contributed to the Refuge wetlands in 2004 than in 2003.Differences in climatic conditions and runoff to the wetlands between years might have resulted in smaller contributions of new Hg to the Refuge wetlands in 2004 than in 2003. 

Whole-water THg concentrations ranged from 0.87 ng/L 

for site 3 (SM1THL04) for 2004 to 17.2 ng/L for site 38 (SS1KRU03) for 2003 (supplement 4). Most whole-water THg concentrations (the middle 80 percent) were between 1.60 and 8.71 ng/L (fig. 4). For 2003, the median whole-water THg concentration for lake wetlands (1.58 ng/L) was less than that for 

temporary wetlands (4.52 ng/L) which was less than that for semipermanent wetlands (6.99 ng/L) which was less than that for seasonal wetlands (7.92 ng/L) (fig. 4). For 2004, the median whole-water THg concentration for lake wetlands (2.37 ng/L) was less than that for semipermanent wetlands (3.95 ng/L) which was less than that for seasonal wetlands (4.52 ng/L) which was less than that for temporary wetlands (6.48 ng/L) (fig. 4). Within types, median whole-water THg concentrations were larger for 2003 than for 2004 for seasonal and semipermanent wetlands and were smaller for 2003 than for 2004 for temporary and lake wetlands. For wetlands sampled in both 2003 and 2004, whole-water THg concentrations were larger for 2003 than for 2004 for site 38 (SS1KRU03) and site 27 (SM1CNC03), were about equal for 2003 and 2004 for site 30 (TP1ASP03) and site 40 (LK1KRU03), and were smaller for 2003 than for 2004 for site 12 (LK1THL03).

which was less than that for seasonal wetlands (0.75 ng/g) (fig. 5). For 2004, the median bottom-sediment MeHg concentration for semipermanent and lake wetlands (less than 0.4 ng/g) 

was less than that for temporary wetlands (1.30 ng/g) which was less than that for seasonal wetlands (1.68 ng/g) (fig. 5). Within types, median bottom-sediment MeHg concentrations were smaller for 2003 than for 2004 for temporary and seasonal wetlands and were about equal for 2003 and 2004 for semipermanent and lake wetlands. For wetlands sampled in both 2003 and 2004, bottom-sediment MeHg concentrations were smallerfor 2003 than for 2004 for site 30 (TP1ASP03), site 38 (SS1KRU03), and site 27 (SM1CNCO3) and were about equal between 2003 and 2004 for site 40 (LK1KRU03) and site 12 (LK1THL03).

Bottom-sediment THg concentrations ranged from 6.77 

ng/g for site 36 (LK1WWH03) for 2003 to 99.0 ng/g for site 7 

(TP2WLD04) for 2004 (supplement 4). Most bottom-sediment THg concentrations (the middle 80 percent) were between 19.7 and 62.4 ng/g (fig. 5). For 2003, the median bottom-sediment THg concentration for lake wetlands (21.7 ng/g) was less than that for temporary wetlands (31.4 ng/g) which was less than that for seasonal wetlands (50.5 ng/g) which was less than that for semipermanent wetlands (51.2 ng/g) (fig. 5). For 2004, the median bottom-sediment THg concentration for lake wetlands (10.1 ng/g) was less than that for seasonal wetlands (40.8 ng/g) which was less than that for semipermanent wetlands (42.8 ng/g) which was less than that for temporary wetlands (71

3 
18 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

Bottom-sediment percent loss on ignition (LOI) is an 

index of the amount of organic material in bottom sediment; LOI increases with increasing concentrations of organic material. Bottom-sediment LOI values ranged from 1.3 percent for 

site 12 (LK1THL03) for 2004 to 51.0 percent for site 19 (SM2CNC04) for 2004 (supplement 4). For 2003, the median bottom-sediment LOI value for lake wetlands (10.7 percent) was less than that for temporary wetlands (17.6 percent) which was less than that for seasonal wetlands (23.5 percent) which was less than that for semipermanent wetlands (32.0 percent) (fig. 5). For 2004, the median bottom-sediment LOI value for lake wetlands (5.9 percent) was less than that for temporary wetlands (29.6 percent) which was less than that for seasonal wetlands (31.8 percent) which was less than that for semipermanent wetlands (32.5 percent) (fig. 5). Within types, medianbottom-sediment LOI values were smaller for 2003 than for 2004 for temporary, seasonal, and lake wetlands and were about equal for 2003 and 2004 for semipermanent wetlands. Forwetlands sampled in both 2003 and 2004, bottom-sedimentLOI values were larger for 2003 than for 2004 for site 30 (TP1ASP03) and site 12 (LK1THL03) and were smaller for 2003 than for 2004 for site 38 (SS1KRU03), site 27 (SM1CNC03), and site 40 (LK1KRU03).

The Refuge wetlands vary in concentrations of Hg constituents and values of bottom-sediment properties among wetland 

types and between years. Notable patterns in concentrations of Hg constituents and LOI values are as follow: (1) whole-water 

and were larger for 2003 than for 2004 for seasonal, semipermanent, and lake wetlands (fig. 6). For wetlands sampled in both 

2003 and 2004, differences in turbidity values between years were variable (supplement 2). Notable patterns in turbidity are as follow: (1) turbidity values for the Refuge wetlands generally were moderate, and (2) differences in turbidity patterns among wetland types were not substantial.

Dissolved-oxygen concentrations ranged from 1.3 milligrams per liter (mg/L) for site 38 (SS1KRU03) for 2003 to 17.5 

mg/L for site 15 (SS2WLD04) for 2004 (supplement 2). Diel variability in dissolved-oxygen concentrations within a given wetland can be substantial. Because individual wetlands were sampled at varying times of day, comparisons of dissolvedoxygen concentrations between wetlands and among wetland types might be substantially affected by sampling times. Thus, these comparisons should be considered qualitative and used with caution. Substantial overlap in the distribution of dissolved oxygen generally occurred among wetland types (fig. 6), but concentrations tended to be smallest in seasonal and semipermanent wetlands. Within types, median dissolved-oxygen concentrations generally were smaller for 2003 than for 2004. For wetlands sampled in both 2003 and 2004, dissolved-oxygen concentrations also generally were smaller for 2003 than for 2004 (supplement 2).

Patterns in dissolved-oxygen concentrations in the Refuge 

wetlands are quite variable. The wetlands are relatively shallow and subject to aeration through wind-generated turbulence. 
Wetland type

0.1

1

10

100

1,000

Turbidity, in nephelometric turbidity units

101520

, in milligrams per liter

10

100

1,000

10,000

Specific conductance, in microsiemens per centimeter

2003 2004

(6) (9) (3) (6) (3) (10) (8) (4)(6) (9) (3) (6) (3) (10) (8) (4)

2003 2004

(6) (9) (3) (6) (3) (10) (8) (4)(6) (9) (3) (6) (3) (10) (8) (4)

2030

re, in degrees Celsius

Wetland type

Wetland type Wetland type

TP SS SM LK TP SS SM LK TP SS SM LK TP SS SM LK

Mercury and Methylmercury in Water and Bottom Sediments 19
20 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

to the variability in pH in these wetland types include concentrations of organic acids, exchange of dissolved carbon dioxide between the wetland water and the atmosphere, dissolution of carbonate minerals as water interacts with geologic materials, and biological processes (including photosynthesis and respiration) that either consume or produce dissolved carbon dioxide that forms carbonic acid and lowers pH. Sulfate reduction also can affect pH by production of bicarbonate ions and consumption of hydronium ions. For environmental Hg studies, consideration of pH is important because Hg and MeHg frequently are shown to be inversely related to pH (Wiener and others, 2003), and low pH often is associated with high MeHg production rates.

Specific-conductance (an index of dissolved solids) values 

ranged from 40 microsiemens per centimeter (

μS/cm) for site 

30 (TP1ASP03) for 2003 to 38,800 

μS/cm for site 43 

(LK1ELS04) for 2004 (supplement 2). The median specificconductance value for temporary wetlands was less than that for seasonal wetlands which was less than that for semipermanent wetlands which was less than that for lake wetlands for both 2003 and 2004 (fig. 6). Within types, median specificconductance values were larger for 2003 than for 2004 for temporary wetlands and were smaller for 2003 than for 2004 for 

seasonal, semipermanent, and lake wetlands. For wetlands sampled in both 2003 and 2004, specific-conductance values were larger for 2003 than for 2004 for site 30 (TP1ASP03) and were smaller for 2003 than for 2004 for site 38 (SS1KRU03), site 27 

ature for temporary wetlands was higher than that for seasonal wetlands which was higher than those for semipermanent and lake wetlands for both 2003 and 2004 (fig. 6). Within types, water temperatures were slightly higher for 2003 than for 2004 for temporary and seasonal wetlands and were about equal for 2003 and 2004 for semipermanent and lake wetlands. For wet- lands sampled in both 2003 and 2004, water temperatures were about equal for 2003 and 2004, varying by less than about 3oC (supplement 2). Variability in water temperatures among wetland types probably reflects geomorphologic characteristics of the wet- lands. Temporary and seasonal wetlands are shallower than the other wetlands, and water temperatures increase more quickly with rising air temperatures in the spring. Semipermanent and lake wetlands are deeper than the other wetlands and have greater volumes, and water temperatures respond more slowly to rising air temperatures in the spring. Differences in water temperatures between 2003 and 2004 appear to be relatively small. Water temperature can have a substantial role in Hg envi- ronmental chemistry because high water temperatures tend to increase bacterial metabolic rates, which can result in high rates of sulfate reduction and increase Hg methylation. Notable patterns in water-quality properties and constitu- ents are as follow: (1) overlap in the distribution of dissolved oxygen generally occurred among wetland types, but concen- trations tended to be smallest in seasonal and semipermanent wetlands and generally were smaller for 2003 than for 2004 for 
2003 2004

(6) (9) (3) (6) (3) (10) (8) (4)

(6) (9) (3) (6) (3) (10) (8) (4)

10

100

1,000

10,000

1,000

10,000

Dissolved solids, in milligrams per liter

100

ligrams per liter

Wetland type Wetland type

TP SS SM LK TP SS SM LK

(4)

 EXPLANATIONBox plot Number of values Upper detached Upper adjacent 75th percentile Median 25th percentile Lower adjacent Lower detachedTemporarywetlandsSeasonalwetlands

TP

SS

SM

LK

Semipermanent wetlandsLake wetlandsStudy reporting level--Individualdata points or parts of box plotsthat plot below the study reportinglevel indicate less-than valuesthat were arbitrarily assigneda value of one-half the studyreporting levelData point--When the number ofvalues shown in parentheses isgreater than the number of datapoints shown in the graph, somedata points are underlying otherdata points

Mercury and Methylmercury in Water and Bottom Sediments 21
1,000

100

10

0.01

0.001

1

0.1

1,000

100

10

1

Concentration, in milliequivalents per liter

22 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
Mercury and Methylmercury in Water and Bottom Sediments 23

Dissolved-sulfate concentrations ranged from less than 

0.30 mg/L for site 7 (TP2WLD04) for 2004 to 21,000 mg/L for site 43 (LK1ELS04) for 2004 (supplement 3). The median

dissolved-sulfate concentrations for temporary wetlands (4.6 and 0.32 mg/L for 2003 and 2004, respectively) were less than those for seasonal wetlands (24 and 152 mg/L for 2003 and 2004, respectively) which were less than those for semipermanent wetlands (189 and 841 mg/L for 2003 and 2004, respectively) which were less than those for lake wetlands (422 and 5,200 mg/L for 2003 and 2004, respectively) (fig. 7). Within types, dissolved-sulfate concentrations generally were larger for 2003 than for 2004 for temporary wetlands and were smaller for 2003 than for 2004 for seasonal, semipermanent, and lake wetlands. For wetlands sampled in both 2003 and 2004,dissolved-sulfate concentrations were larger for 2003 than for 2004 for site 30 (TP1ASP03) and were smaller for 2003 than for 2004 for site 38 (SS1KRU03), site 27 (SM1CNC03), site 40 (LK1KRU03), and site 12 (LK1THL03). About 90 percent of the wetlands had dissolved-sulfate concentrations that exceeded 2 mg/L, which is near the concentration below which substantial sulfate reduction generally does not occur. However, only about 50 percent of the temporary wetlands had dissolvedsulfate concentrations that exceeded 2 mg/L. Adequatedissolved sulfate might be a factor that limits Hg methylation in temporary wetlands in the Refuge. Sulfate concentrations in lake wetlands generally are large, and the accumulation of large concentrations of free sulfide in pore waters of the lake wetl

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Runoff to the Refuge wetlands in 2004 probably was substantially smaller than in 2003 and resulted in smaller contributions 

of dilute atmospheric water in 2004. The decrease in dilution in 2004 might have increased effects of evaporative concentration and mineral precipitation processes, resulting in greater proportions of sulfate for most wetland types in 2004.

Patterns in dissolved-solids concentrations among wetland 

types and between years (fig. 7) are similar to those for specific conductance (fig. 6), which is an index of dissolved-solids concentration. The patterns for specific conductance and the factors 

that contribute to the patterns were discussed previously in this report.

Notable patterns in major-ion constituents for the Refuge 

wetlands are as follow: (1) dissolved-solids concentrations were smaller for temporary wetlands than for the other wetlands, were intermediate for seasonal and semipermanent wetlands, and were larger for lake wetlands than for the other wetlands for both 2003 and 2004; (2) dissolved-solids concentrations were substantially smaller for 2003 than for 2004 for all wetland types except temporary wetlands; (3) dissolved-sulfate concentrations varied among wetland types and between years in a 

manner similar to that for dissolved-solids concentrations; (4) the proportion of sulfate among major ions was larger for semipermanent and lake wetlands than for temporary and seasonal wetlands and also for 2004 than for 2003 for all wetland types except temporary wetlands; (5) sulfate concentrations in temporary wetlands generally were small and might limit sulfate 
2003 2004

(6) (9) (3) (6) (3) (10) (8) (4)

(6) (9) (3) (6) (3) (10) (8) (4)

0.1

1

10

100

Dissolved barium, in micrograms per liter

10

100

1,000

e, in micrograms per liter

Wetland type Wetland type

TP SS SM LK TP SS SM LK

(4)

 EXPLANATIONBox plot Number of values Upper detached Upper adjacent 75th percentile Median 25th percentile Lower adjacent Lower detachedTemporarywetlandsSeasonalwetlands

TP

SS

SM

LK

Semipermanent wetlandsLake wetlandsStudy reporting level--Individualdata points or parts of box plotsthat plot below the study reportinglevel indicate less-than valuesthat were arbitrarily assigneda value of one-half the studyreporting levelData point--When the number ofvalues shown in parentheses isgreater than the number of datapoints shown in the graph, somedata points are underlying otherdata points

24 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
Mercury and Methylmercury in Water and Bottom Sediments 25

Within types, median dissolved-manganese concentrations were smaller for 2003 than for 2004 for temporary and lake wetlands, were equal for 2003 and 2004 for seasonal wetlands, and were larger for 2003 than for 2004 for semipermanent wetlands. For wetlands sampled in both 2003 and 2004, dissolvedmanganese concentrations were larger for 2003 than for 2004 for site 30 (TP1ASP03) and were smaller for 2003 than for 2004 for site 38 (SS1KRU03), site 27 (SM1CNC03), site 40 (LK1KRU03), and site 12 (LK1THL03). As for barium, manganese solubility is strongly linked to oxidation-reductionprocesses, especially those involving adsorption/desorption from clays and oxide and hydroxide compounds (Hem, 1985). Oxidation-reduction processes that promote solubility ofmanganese previously have been noted to be associated with production of MeHg (Bonzongo and others, 1996). Patterns in manganese concentrations might provide information on variability in oxidation-reduction conditions at the sediment/water interface in the Refuge wetlands.

The notable pattern in non-Hg trace-element constituents 

for the Refuge wetlands is that barium and manganese concentrations, which are strongly dependent on oxidation-reduction 

processes, generally were largest for seasonal and semipermanent wetlands.Organic-Carbon Constituents in Water Samples

St

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mulation sites for particulate organic matter. Among different kinds of wetlands, DOC concentrations in northern prairie wet- lands tend to be high; concentrations routinely exceed 20 mg/L and sometimes exceed 100 mg/L (Arts and others, 2000). Wet- land complexes generally have a larger ratio of littoral (that is, in or near the land/water interface) area to open-water area than most other freshwater aquatic systems. The littoral zone sup- ports emergent and submergent aquatic vegetation (with associ- ated epiphytic algae) and accounts for extremely high rates of primary productivity (Wetzel, 1992). When vegetation in or near wetlands dies in the fall (or as wetland water levels recede during summer), the dead particulate organic matter generally is deposited near the production site where it undergoes decompo- sition, producing soluble organic byproducts. In spring, surface runoff, interflow (that is, water that infiltrates the soil surface, travels generally laterally through the vadose zone, and then discharges to the surface at a point down slope), or interaction between rising water levels and previously dry wetland soils mobilizes soluble organic compounds in various stages of decomposition (Wetzel, 1992) and transports them to the wet- land water. Thus, most organic carbon entering prairie wetland water is a complex mixture of dissolved compounds that typi- cally is composed largely of humic substances with high bio- and photoreactivity (Curtis and Adams, 1995; Amon and Benner, 1996; Waiser and Robarts, 2004). As DOC resides in wetland water, it is progressively degraded by both biotic processes (Tulonen and others, 1992; 
2003 2004

(6) (9) (3) (6) (3) (10) (8) (4)

150200

, in milligrams per liter

(4)

 EXPLANATIONBox plot Number of values Upper detached Upper adjacent 75th percentile

TP

SS

SM

Temporary wetlandsSeasonal wetlandsSemipermanent wetlands

26 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refugeulating organic carbon use and DOC production. DOC also can be contributed to these wetlands by surface runoff and interflow. Because of shorter inundation times in the temporary and seasonal wetlands than in the other wetlands, less opportunity exists for biotic and abiotic processing of organic carbon in the wetland water column. Semipermanent wetlands are inundated throughout the year in some years, and lake wetlands areinundated throughout the year in nearly all years (Cowardin and others, 1979). These wetlands receive new DOC during spring melt periods and runoff events. However, organic carbon can remain in the wetland water column for relatively long periods in semipermanent wetlands and for very long periods in lake wetlands and can undergo extensive biotic and abiotic processing that can affect both the concentration and composition of 

DOC (Tulonen and others, 1992; Amon and Benner, 1996; del Giorgio and Cole, 1998; Miller, 1998; Waiser and Robarts, 2004). Thus, DOC in temporary and seasonal wetlands might be expected to consist of a larger proportion of reactive DOC than DOC in semipermanent and lake wetlands. Another factor that might contribute to differences in DOC concentrations among wetland types is that seasonal and semipermanent wetlands generally have more dense vegetation growth in and near the wetlands, which might result in greater contributions of new DOC to these wetland types during runoff periods.

DOC concentrations ranged from 8.2 mg/L for site 30 

(TP1ASP03) for 2004 to 154 mg/L for site 43 (LK1ELS04) for 2004 (supplement 4). For 2003, the median DOC concentrations for temporary and lake wetlands (22.4 and 24.5 mg/L, 
Mercury and Methylmercury in Water and Bottom Sediments 27

respectively) were less than those for seasonal and semipermanent wetlands (38.6 and 32.4 mg/L, respectively) (fig. 10). These DOC concentrations are large relative to those in most natural aquatic systems, probably demonstrating high levels of carbon use in the sediments of the Refuge wetlands. For 2004, the median DOC concentrations for temporary, seasonal, and semipermanent wetlands were similar (25.5, 28.0, and 30.0 mg/L, respectively) and were less than the median for lake wetlands (52.0 mg/L). Within types, median DOC concentrations generally were similar for 2003 and 2004 for temporary and semipermanent wetlands, were larger for 2003 than for 2004 for seasonal wetlands, and were smaller for 2003 than for 2004 for lake wetlands. For wetlands sampled in both 2003 and 2004, DOC concentrations were larger in 2003 than in 2004 for site 30 (TP1ASP03) and were smaller for 2003 than for 2004 for site 38 (SS1KRU03), site 27 (SM1CNC03), site 40 (LK1KRU03), and site 12 (LK1THL03). Temporary wetlands generally had smaller DOC concentrations than the other wetland types. For seasonal, semipermanent, and lake wetlands, DOC concentrations generally were relatively large. However, for these types, ranges within types and differences among types and between years generally were quite variable.

Notable patterns in DOC concentrations are as follow: (1) 

during the wet climatic conditions of 2003, DOC concentrations for seasonal and semipermanent wetlands were larger than those for temporary and lake wetlands; (2) DOC concentrations for seasonal wetlands generally were substantially larger for 

Hg chemistry in aquatic systems and the limited scope of this study, several assumptions were used: (1) atmospheric deposition of inorganic Hg was relatively spatially uniform throughout the Refuge during the study period; (2) differences in concentrations of MeHg among wetland types and between years 

primarily represent differences in concentrations of bioavailable inorganic Hg for methylation and/or differences in conditions that affect rates of sulfate reduction and, thus, rates of Hg methylation in the wetlands; (3) differences in concentrations of 

MeHg among wetland types and between years probably were not strongly affected by differences in rates of demethylation; and (4) differences in concentrations of Hg among wetland types and between years probably was not strongly affected by differences in rates of volatilization of dissolved gaseous Hg. Although specific data to support these assumptions were not collected during this study, the assumptions probably are reasonable. Photochemical reactions can strongly affect concentrations of MeHg through photo-demethylation reactions 

(Krabbenhoft and others, 2002) and, to a lesser degree, concentrations of inorganic Hg through photoreduction of Hg+2 to 

Hg0, which can volatilize to the atmosphere (Krabbenhoft and 

others, 1998). All of the Refuge wetlands are relatively shallow, well mixed as a result of wind-generated turbulence, and elevated in DOC. Previous studies have indicated that ultravioletlight wavelengths are most responsible for facilitating photochemical reactions that involve Hg and MeHg in surface waters 

(Krabbenhoft and others, 1998; Krabbenhoft and others, 2002). 

OC 

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28 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

the relations are illustrated by scatter plots of dissolved solids, DOC, MeHg, and THg concentrations in relation to pH for the various types of Refuge wetlands for 2003 and 2004 combined (fig. 11). LOWESS smooth lines (Cleveland and McGill, 1984; Cleveland, 1985) that show the central tendencies of the relations were used in the scatter plots to help discern the relations among the variables (Helsel and Hirsch, 1992). The smooth lines do not imply statistically significant relations. Rather, because many of the biogeochemical factors that affect the occurrence of Hg and MeHg in natural aquatic systems (including DOC processing, sulfate reduction, and Hg solubility) also affect or are affected by pH, the relatively large pH gradient that occurs across the different wetland types on the Refuge and between the 2 years of sampling provides a convenient index for examining factors that affect Hg and MeHg concentrations in the wetlands. The Refuge wetlands show a clear gradation in pH that is related to the specific wetland’s hydroperiod, such that more ephemeral wetlands generally have relatively low pH, and perennially flooded lakes generally have relatively high pH(fig. 6). Presenting relations between dissolved solids, DOC, MeHg, THg, and pH for all wetland types and both 2003 and 2004 data combined might result in an oversimplification of specific processes that could have been occurring in individual wetlands. However, some patterns that probably represent important biogeochemical processes that were likely to have occurred are evident.

In the Refuge wetlands, relatively small dissolved-solids 

For the relatively low pH (values of less than about 8 standard units) generally typical of the temporary and seasonal

wetlands, relatively large variability occurred in the relation between dissolved solids and pH. In this pH range, the primary determinants of dissolved solids and pH probably are less strongly associated. Several seasonal wetlands and a semipermanent wetland that were sampled in 2004 had relatively high pH (values ranging from 9.5 to 9.7 standard units) and relatively small dissolved-solids concentrations (ranging from 251 to935 mg/L). This group of wetlands deviates from the general relation between dissolved solids and pH among the Refuge wetlands. A possible explanation for the dissolved-solids and pH characteristics of this group of wetlands is that the water that occurred in the wetlands in 2004 was predominantly carry-over water from 2003 as opposed to new water contributed fromrunoff or recent precipitation. These conditions might be arelatively infrequent occurrence for these wetlands. Seasonal wetland sampling site SS1KRU03 (specifically labeled infigure 11), which was sampled in both 2003 and 2004 and is among the group of wetlands that deviates from the general relation, provides evidence for the possible explanation. During the wet climatic conditions of 2003, SS1KRU03 had a relatively small dissolved-solids concentration of 108 mg/L and a relatively low pH of 6.5 standard units (fig. 11

A), indicating the 

water in the wetland was predominantly of recent atmospheric origin. During the dry climatic conditions of 2004, SS1KRU03 had a dissolved-solids concentration of 442 mg/L and a pH of 9

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10

100

1,000

10,000

100,000

Dissolved solids, in milligrams per liter

A

100

arbon, in milligrams per liter B

SS1KRU03

SM1CNC03

LK1THL03

SS1KRU03 SM1CNC03

TP1ASP03

SS1KRU03

SM1CNC03

SM1CNC03

LK1KRU03

LK1KRU03

LK1THL03

LK1THL03

SS1KRU03

TP1ASP03

Mercury and Methylmercury in Water and Bottom Sediments 29
0.01

0.1

1

10

Whole-water total mercury, in nanograms per liter C

1

10

mercury, in nanograms per liter D

TP1ASP03

SS1KRU03

SM1CNC03

LK1KRU03 LK1THL03

TP1ASP03

SS1KRU03

SM1CNC03

LK1KRU03

LK1THL03

TP1ASP03

SS1KRU03

SM1CNC03

LK1THL03

SS1KRU03

SM1CNC03

30 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
Mercury and Methylmercury in Water and Bottom Sediments 31

During winter, the depressional wetlands serve as accumulation points for snowfall. In the spring, the temporary, seasonal, and semipermanent wetlands are reflooded from snowmelt and spring rains (water of recent atmospheric origin and, thus, relatively low pH), and the soils rapidly evolve from aerobic to anaerobic conditions. Following reflooding, microbial process rates increase, using abundant labile organic carbon in sediments produced during the dessication period. Organic carbon use results in the release of DOC (consisting mostly of acidic humic substances; Thurman, 1985) to surface water. Runoff from adjacent terrestrial areas also can contribute DOC to the wetlands. The new DOC contributes to relatively low pH and enhances Hg solubility through complexation with organic ligands. With time, the humic substances are progressively metabolized and/or photochemically bleached to smaller and less complex aliphatic organic carbon compounds with low reactivity (Tulonen and others, 1992; Amon and Benner, 1996; del Giorgio and Cole, 1998; Miller, 1998; Waiser and Robarts, 2004). Associated with this process is an increase in pH as a result of several processes, including metabolic and photolytic alteration of the acidic humic substances, sulfate reduction (which generates bicarbonate and consumes hydronium ions), prolonged interaction with geologic materials, and common-ion effects of evaporative concentration (Banks and others, 2004). During the progressive metabolization, some of the DOC is incorporated into biomass and some is excreted or released back into the water. At some point, the availability of the degrading 

OC f

b

i

l 

i

ll

d 

i

i

types, relatively large THg concentrations also generally were associated with relatively large DOC concentrations (fig. 12), 

further supporting the role of DOC complexation in maintaining THg in the water column. Another factor that might affect the relation between THg and DOC is contributions of new water into the wetlands during snowmelt and runoff events. Because of the contributions of new DOC from the new water, the potential for the addition of new inorganic Hg is greater than during dry periods. Hg retained in the melting snowpack and on or in dead vegetation and oxidized soils might be mobilized during inundation and runoff. Thus, similar patterns in occurrence of THg and DOC across the pH gradient might also indicate that factors that affect differences in loading of new DOC among wetland types and between years also affect differences in loading of new inorganic Hg. During dry spring conditions, such as those that occurred in 2004, contributions of both new DOC and new inorganic Hg probably are small. However, some factors contribute to variability between patterns in THg and DOC across the pH gradient. DOC concentrations associated with high pH (that is, values of more than about 9.5 standard units) tend to be similar to or larger than those associated with low pH (values of less than about 7 standard units). Conversely, THg concentrations associated with high pH tend to be smaller than those associated with low pH. These patterns might indicate the occurrence of processes that result in removal of THg from the water column at a rate that exceeds effects of evaporative concentration on DOC. These processes might include semiperma

d

i

i

i

di

d/

l

ili

i

f 

0 

h
Temporary wetlands

Semipermanent wetlands

Seasonal wetlands

SS1KRU03

SS1KRU03

TP1ASP03

TP1ASP03

2003 2004

EXPLANATION

SS1KRU03

1

10

l mercury, in nanograms per liter

0.1

1

10

0.1

LOWESS smooth lineTemporary wetlandSeasonal wetlandSemipermanent wetlandLake wetlandSampling site name(given in table 3)--Shownfor sites sampled in both2003 and 2004

32 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge
Mercury and Methylmercury in Water and Bottom Sediments 33

centrations as large as those in seasonal and semipermanent wetlands, partly because effects of drying cycles are less pronounced with less stimulation from oxidation of the sediments. Thus, although some exceptions exist, the general relation between MeHg and pH is that relatively large MeHg concentrations generally are associated with relatively low pH, and relatively small MeHg concentrations are associated with relatively high pH. Although the relation between MeHg and pH is relatively strong, pH probably does not have a direct dominant role 

in MeHg production. Rather, the interaction of several factors that occur across the pH gradient affect the resultant pattern.

Variability in dissolved-sulfate concentrations also can 

affect MeHg production. Relations between whole-water MeHg and dissolved sulfate for the various wetland types indicate the direct effects of sulfate concentrations on sulfate-reduction and Hg-methylation processes. Relations for seasonal and semipermanent wetlands (which generally had large MeHg concentrations) are shown in figure 13

A

SS1KRU03

SM1CNC03

B (Seasonal and semipermanent wetlands)

2003 2004

1

10

anograms per liter

A (Seasonal and semipermanent wetlands)

SS1KRU03

SM1CNC03

0.1

for 2003 and in figure 13

B for 
34 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

2004, and relations for temporary and lake wetlands (which generally had small MeHg concentrations) are shown in figure 13

C for 2003 and in figure 13

D for 2004. Relatively small

sulfate concentrations result in relatively low rates of sulfate reduction; thus, little MeHg is produced (Gilmour and Krabbenhoft, 2001). Relatively large sulfate concentrations can result in high rates of sulfate reduction and accumulation of free sulfide in pore waters. Highly sulfidic environments appear to inhibit MeHg production although the mechanism by which thathappens is not clear (Wiener and others, 2003). Intermediate sulfate concentrations have been shown to result in maximal MeHg production in other wetlands and stream ecosystems (Hurley and others, 1998; Krabbenhoft and others, 1999).

The largest MeHg concentrations (that is, greater than 

1 ng/L) that occurred in the Refuge wetlands were associated 

with sulfate concentrations that ranged from about 5 to 280 mg/L. That range is a relatively narrow and intermediate interval at the low end of the overall range of sulfate concentrations 

in the Refuge wetlands (less than 0.30 to 21,000 mg/L). Concentrations in seasonal and semipermanent wetlands in 2003 (fig. 13

A) show the convex relation between MeHg and dissolved sulfate commonly reported in other studies (U.S. Department of Commerce, National Oceanic and Atmospheric 

Administration, National Oceanic Service, 1996; Hurley and others, 1998; Krabbenhoft and others, 1999). However, the relation is not apparent in concentrations in seasonal and semipermanent wetlands in 2004. Several seasonal and semiperma

intermediate dissolved-sulfate concentration of 14 mg/L, a relatively large DOC concentration of 46.9 mg/L, a large THg concentration of 17.2 ng/L, and a large MeHg concentration of 9.6 

ng/L. The relatively low pH, relatively small dissolved-solids concentration, and relatively large DOC concentration indicate the water in the wetland was predominantly of recent atmospheric origin and had abundant DOC with relatively high bioreactivity. The concomitant association of a large THg concentration probably indicates that processes that contributed both new DOC and new THg occurred and that substantial THg was maintained in the water column as a result of complexation with abundant DOC. The further concomitant association of a large MeHg concentration probably indicates that the abundant DOC with high bioreactivity was either being produced by or serving as a substrate for high rates of microbial activity (including sulfate reduction) and that the substantial THg was bioavailable to sulfate-reducing bacteria and was being actively methylated. The intermediate dissolved-sulfate concentration was adequate for sulfate reduction to occur but not large enough to promote excessive accumulation of free sulfide. During the dry climatic conditions of 2004, the pH value for SS1KRU03 had substantially increased to 9.7 standard units, the dissolvedsolids concentration had increased to 442 mg/L, the dissolvedsulfate concentration had increased to 213 mg/L, the DOC concentration had moderately increased to 66.9 mg/L, the THg concentration had substantially decreased to 4.3 ng/L, and the MeHg concentration had very substantially decreased to 0

38 
Summary and Conclusions 35

General water-quality characteristics of the Refuge wetlands vary substantially among wetland types and between 

years and result in notable patterns in occurrence of wholewater MeHg in the wetlands. Of the 44 wetlands sampled during this study, 11 had relatively large MeHg concentrations (that is, greater than 1 ng/L). Of these 11 wetlands, 7 were seasonal wetlands, 3 were semipermanent wetlands, and 1 was a temporary wetland. MeHg concentrations for three of the seasonal wetlands are considered very large (ranging from about5 to 10 ng/L). Seasonal and semipermanent wetlands at theRefuge generally had larger MeHg concentrations than temporary and lake wetlands. All wetland types generally had substantially larger MeHg concentrations during the wet climatic conditions of 2003 than during the dry climatic conditions of 2004. Conditions associated with the largest whole-water MeHg concentrations (greater than 1 ng/L) include THg concentrations generally greater than about 4 ng/L, pH values less than about 8 standard units in conjunction with DOC concentrations generally greater than about 20 mg/L, and intermediate sulfate concentrations (generally between about 5 and 280 mg/L). These conditions generally were more prevalent in 2003 than in 2004 and were affected by the substantial snowmelt and runoff that occurred prior to sample collection. The distinct differences in MeHg concentrations between 2003 and 2004 indicate the importance of seemingly unrelated factors (such as climate) in regulating the formation of MeHg in the environment.

ting and drying cycles, that are intrinsic to prairie pothole wet- lands, affected MeHg concentrations. This likely resulted from the stimulation of anaerobic microbial activity following reflooding of soils, particularly soils containing substantial organic carbon. Among the four wetland types considered for this study, seasonal and semipermanent wetlands generally had the largest MeHg concentrations. Lake wetlands, which do not undergo drying cycles, generally had the smallest MeHg con- centrations. Temporary wetlands, which have the greatest fre- quency and longest duration of drying cycles, had intermediate MeHg concentrations that, in part, might reflect the limited amount of time (generally just a few weeks of inundation) these systems have to produce MeHg. Regardless of wetland type, however, MeHg concentrations at the Refuge are large in rela- tion to reported concentrations for natural aquatic systems. Whole-water MeHg concentrations generally decrease with increases in pH, which generally is the relation reported in previously published Hg studies. The processing of organic carbon in soil and sediment is a major factor in regulating Hg cycling, especially MeHg production, in the environment. Dissolved organic carbon (DOC) concentrations at the Refuge are large (semipermanent and lake wetlands had DOC concen- trations that exceeded 50 milligrams per liter), indicating the importance of organic carbon substrates for anaerobic processes occurring in those wetlands. DOC is mostly a byproduct of sed- 
36 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

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contamination in Florida largemouth bass: Proceedings of the 

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d C

i

d

db

k 

f 

i

l

2

d 
Supplements 1–6
40 Mercury and Methylmercury in Water and Bottom Sediments of Wetlands, Lostwood National Wildlife Refuge

Supplement 1: Quality Assurance/Quality 

Control 

Quality-assurance/quality-control (QA/QC) samples collected during this study consisted of field-equipment blank and 

replicate samples to assess precision and accuracy of collected data. Blank samples provide information on potential effects of contamination during collection, processing, and laboratory analysis on analytical results. Replicate samples provide information on the precision or reproducibility of analytical results.Quality-Assurance/Quality-Control Data Collection

Field-equipment blank samples were collected by passing 

ultra-pure water through the collection and processing equipment used for primary environmental samples. The procedures 

used to collect and process the samples were identical to those used for the environmental samples. A field-equipment blank sample with constituent concentrations equal to or less than the study reporting level for a given constituent indicates the overall process of sample collection, processing, and laboratory analysis is not introducing substantial contamination. Sporadic, infrequent detections at concentrations near the study reporting level probably represent random contamination or instrument calibration error that is not persistent in the process and that is 

where

S is the standard deviation of the difference in

concentration between replicate analyses, and

d is the difference in concentration between each pair

of replicate analyses.

Precision also can be expressed as a relative standard deviation ( ) RSD , in percent, which is computed from the standard 

deviation and the mean concentration for each replicate pair. Expressing precision relative to a mean concentration standardizes comparison of precision among individual constituents. The RSD, in percent, is calculated according to the following equation:

RSD

S

X

= ---*100, (2)

where

RSD is the relative standard deviation,

S is the standard deviation, and

X is the mean concentration for a pair of replicate

samples.

For equations 1 and 2, censored concentrations reported as 

less than the study reporting level were arbitrarily assigned a value of one-half the study reporting level.

Q

lit

A

/Q

lit

C

t

l R

lt
Supplement 1 41

Analytical results for replicate samples are given in supplements 3 and 4, immediately following results for associated 

primary environmental samples. Statistical summaries of RSDvalues for pairs of primary environmental/replicate samples are given in supplement 6. Generally, an RSD value of 20 percent or less represents an acceptable level of precision although, for small concentrations near the limit of analytical detectability, the percent differences can be substantially larger and stillbe considered reasonable because of the limits of resolution (Taylor, 1987).

For this study, most constituents had RSD values less than 

20 percent, indicating the overall process of sample collection, processing, and analysis was producing consistent results. Many of the RSD values were near 10 percent or less. However, several constituents, including carbonate, suspended solids,dissolved aluminum, dissolved chromium, dissolved copper, dissolved iron, dissolved manganese, dissolved selenium,dissolved zinc, dissolved and suspended MeHg, and suspended THg in water samples and MeHg and THg in bottom-sediment samples, had one or more replicate pairs with RSD values greater than 20 percent.

Carbonate, dissolved chromium, dissolved copper, dissolved selenium, and dissolved MeHg each had only one replicate pair with an RSD value that exceeded 20 percent. Those 

cases generally were for concentrations near the study reporting levels. Given the acceptable precision for most of the replicate pairs and consideration of limits of resolution at small concen

porated into either the dissolved or suspended samples. At the small concentrations that suspended Hg occurred in the sam- ples, possible slight variability in the sample filtration process likely contributed to the relatively large RSD values for sus- pended Hg constituents. Given these factors, analytical results for suspended MeHg and suspended THg in water samples should be used with caution. However, the general findings of this study indicate the poor precision in the analytical results for suspended MeHg and suspended THg in water samples proba- bly did not obscure patterns in differences in concentrations of those constituents among wetland types. In general, results for replicate samples indicate the overall process of sample collec- tion, processing, and laboratory analysis provided accurate pre- cision and did not substantially bias study results. Suspended MeHg and THg in bottom-sediment samples each had one rep- licate pair with RSD values that exceeded 20 percent. Given the acceptable precision for most of the replicate pairs and consid- eration of possible additional variability in the bottom-sediment sampling process, the precision results for those constituents are considered reasonable and acceptable.
site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

water surface

at sampling

site location

(feet)

pressure

(millimeters

mercury)

conductance

(microsiemens

per

centimeter)

pH

(standard

units)

temperature

(degrees

Celsius)

temper

(degre

Celsi

2003

‘ 4 SS1THL03 4/21/2003 1620 1.1 700 151 7.7 22.0 16.9 

6 SS1WLD03 4/22/2003 1530 1.0 705 843 7.7 20.5 14.0 

9 TP1WLD03 4/22/2003 1330 .5 705 97 7.3 20.5 15.2 

10 SM1WLD03 4/22/2003 1100 .9 705 736 8.2 17.0 10.8 

11 TP1THL03 4/22/2003 0845 1.5 705 112 6.9 10.4 9.9 

12 LK1THL03 4/22/2003 0930 3.9 703 11,600 8.8 6.9 7.4 

18 SS3WDM03 4/24/2003 0830 1.1 700 359 6.8 14.6 10.3 

20 SS2WDM03 4/24/2003 1110 1.4 700 290 7.2 16.4 11.7 

22 SM1WDM03 4/24/2003 1405 1.1 700 744 7.9 24.0 14.7 

22 SM1WDM03 4/24/2003 11410 1.1 700 744 7.9 24.0 14.7 

23 TP1CNC03 4/23/2003 1050 1.9 700 3,890 7.6 20.4 11.4 

25 SS4WDM03 4/24/2003 1630 2.1 698 378 7.1 24.0 15.6 

26 SS1CNC03 4/24/2003 1120 .8 702 348 7.6 13.6 12.3 

27 SM1CNC03 4/23/2003 0900 .8 695 310 7.1 16.8 8.6 

28 LK1SEL03 4/23/2003 1100 3.3 695 298 8.0 18.6 11.9 

28 LK1SEL03 4/23/2003 11105 3.3 695 298 8.0 18.6 11.9 

30 TP1ASP03 4/22/2003 1500 .7 702 511 7.3 20.5 17.0 

31 TP1SEL03 4/23/2003 1430 1.7 695 67 7.0 23.8 16.4 

33 LK1FSC03 4/23/2003 0740 4.3 696 1,280 8.0 15.0 11.1 

34 LK1SSK03 4/24/2003 0950 2.6 702 2,090 8.4 13.2 12.6 

36 LK1WWH03 4/24/2003 0810 3.3 702 22,500 9.1 12.2 10.8 

38 SS1KRU03 4/24/2003 1440 1.0 698 217 6.5 20.4 10.2 

39 SS2KRU03 4/24/2003 1350 1.3 700 87 7.3 14.8 14.8 

40 LK1KRU03 4/22/2003 1330 5.6 704 1,150 8.3 19.8 12.3 

41 TP1WSU03 4/23/2003 1250 .9 700 166 7.8 22.8 17.0 

44 SS1ELN03 4/23/2003 1500 .7 695 109 7.8 21.7 18.1 
2004

1 SS4WLD04 4/28/2004 0800 1.6 679 355 7.1 9.2 11.5 

1 SS4WLD04 4/28/2004 10805 1.6 679 355 7.1 9.2 11.5 

2 SM4WLD04 4/28/2004 0900 .7 680 1,080 8.7 8.4 10.1 

3 SM1THL04 4/28/2004 0800 1.3 682 1,730 8.6 8.9 11.4 

5 SM3WLD04 4/28/2004 1130 .8 680 1,420 7.6 -- 12.0 

7 TP2WLD04 4/28/2004 1115 .3 682 1,080 7.9 -- 12.2 

8 SM2WLD04 4/28/2004 1015 .3 682 720 9.6 -- 12.0 

12 LK1THL03 4/28/2004 1445 1.6 687 13,500 9.1 4.2 10.5 

13 SS1TLS04 4/28/2004 1600 .7 690 743 8.3 2.3 9.1 

14 SS1TWS04 4/26/2004 1245 2.3 707 735 9.6 8.6 15.0 

15 SS2WLD04 4/27/2004 1255 .7 692 114 7.2 18.5 20.1 

16 SS3WLD04 4/27/2004 1155 .7 693 371 7.4 16.0 14.2 

16 SS3WLD04 4/27/2004 11200 .7 693 371 7.4 16.0 14.2 

17 SS1ASP04 4/27/2004 0830 .5 693 826 9.7 -- 8.2 

19 SM2CNC04 4/27/2004 1420 .7 692 2,050 8.4 18.5 18.6 

21 TP2CNC04 4/26/2004 1555 1.0 704 48 7.4 10.2 14.2 

24 SS3CNC04 4/27/2004 1500 1.3 690 143 7.7 -- 18.5 

27 SM1CNC03 4/28/2004 1430 1.3 688 4,590 8.2 -- 9.8 

29 LK1CNC04 4/28/2004 1220 3.3 683 3,210 8.5 7.0 12.4 

30 TP1ASP03 4/26/2004 1435 1.0 705 40 8.2 11.1 13.7 

32 SS1GNN04 4/27/2004 1530 .7 690 486 7.7 24.5 19.9 

35 SM1KRU04 4/27/2004 1020 2.0 693 1,380 9.0 14.4 9.8 

37 SS3KRU04 4/27/2004 0845 1.6 692 352 9.5 11.0 10.1 

38 SS1KRU03 4/27/2004 0930 .7 692 627 9.7 13.8 10.0 

40 LK1KRU03 4/28/2004 1050 2.6 -- 10,600 8.7 9.4 11.8 

42 SM1WLL04 4/28/2004 1520 .3 688 1,210 9.1 -- 7.6 

43 LK1ELS04 4/28/2004 0930 3.3 684 38,800 9.8 9.4 10.9 

1Quality-assurance/quality-control replicate sample.

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Depth to

bottom from

water surface

at sampling

site location

(feet)

Barometric

pressure

(millimeters

mercury)

Specific

conductance

(microsiemens

per

centimeter)

pH

(standard

units)

Air

temperature

(degrees

Celsius)

Wat

temper

(degre

Celsi
Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Hardness,

total,

calculated

(mg/L as

CaCO

3

)

Calcium,

dissolved

(mg/L)

Magnesium,

dissolved

(mg/L)

Sodium,

dissolved

(mg/L)

sodium,

in equivale

of major

cations

(percent

2003

4 SS1THL03 4/21/2003 1620 49 11 5.1<3.09 

6 SS1WLD03 4/22/2003 1530 350 49 56 31 15 

9 TP1WLD03 4/22/2003 1330 28 7.1 2.4 <3.0 14 

10 SM1WLD03 4/22/2003 1100 310 43 50 24 13 

11 TP1THL03 4/22/2003 0845 26 4.8 3.3<3.0 12 

12 LK1THL03 4/22/2003 0930 2,000 12 470 560 37 

18 SS3WDM03 4/24/2003 0830 140 30 16 4.76 

20 SS2WDM03 4/24/2003 1110 98 21 11 3.15 

22 SM1WDM03 4/24/2003 1405 340 75 37 168 

22 SM1WDM03 4/24/2003

11410 340 74 37 16

8 

23 TP1CNC03 4/23/2003 1050 2,200 360 330 170 14 

25 SS4WDM03 4/24/2003 1630 110 25 10<3.04 

26 SS1CNC03 4/24/2003 1120 120 31 10<3.04 

27 SM1CNC03 4/23/2003 0900 200 39 25 54 34 

28 LK1SEL03 4/23/2003 1100 140 28 16 4.66 

28 LK1SEL03 4/23/2003

11105 130 27 16 4.8

7 

30 TP1ASP03 4/22/2003 1500 290 78 24 4.93 

31 TP1SEL03 4/23/2003 1430 17 4.0 1.6<3.0 19 

33 LK1FSC03 4/23/2003 0740 480 53 84 96 28 

34 LK1SSK03 4/24/2003 0950 370 25 75 360 66 

36 LK1WWH03 4/24/2003 0810 860 6.7 200 5,500 92 

38 SS1KRU03 4/24/2003 1440 46 8.8 5.8<3.07 

39 SS2KRU03 4/24/2003 1350 20 4.4 2.2<3.0 15 

40 LK1KRU03 4/22/2003 1330 300 21 60 150 50 

41 TP1WSU03 4/23/2003 1250 56 14 4.9 7.4 19 

44 SS1ELN03 4/23/2003 1500 20 4.2 2.3<3.0 12 
2004

1 SS4WLD04 4/28/2004 0800 150 29 20 7.28 

1 SS4WLD04 4/28/2004

10805 150 28 20 7.3

8 

2 SM4WLD04 4/28/2004 0900 800 130 110 44 10 

3 SM1THL04 4/28/2004 0800 870 100 150 93 18 

5 SM3WLD04 4/28/2004 1130 56 13 5.6 3.2 9 

7 TP2WLD04 4/28/2004 1115 47 11 4.6 <3.0 10 

8 SM2WLD04 4/28/2004 1015 350 74 40 20 9 

12 LK1THL03 4/28/2004 1445 6,500 16 1,600 2,000 39 

13 SS1TLS04 4/28/2004 1600 290 53 39 22 13 

14 SS1TWS04 4/26/2004 1245 440 120 34 104 

15 SS2WLD04 4/27/2004 1255 39 8.6 4.3<3.0 10 

16 SS3WLD04 4/27/2004 1155 220 53 22 4.24 

16 SS3WLD04 4/27/2004

11200 220 54 22 4.4

4 

17 SS1ASP04 4/27/2004 0830 600 150 52 227 

19 SM2CNC04 4/27/2004 1420 1,000 140 170 110 18 

21 TP2CNC04 4/26/2004 1555 16 3.1 1.9<3.0 18 

24 SS3CNC04 4/27/2004 1500 60 14 5.9<3.08 

27 SM1CNC03 4/28/2004 1430 2,100 420 250 410 29 

29 LK1CNC04 4/28/2004 1220 930 40 200 470 51 

30 TP1ASP03 4/26/2004 1435 13 3.7 1.0<3.0 29 

32 SS1GNN04 4/27/2004 1530 200 40 24 9.78 

35 SM1KRU04 4/27/2004 1020 290 29 53 230 61 

37 SS3KRU04 4/27/2004 0845 180 44 17 4.14 

38 SS1KRU03 4/27/2004 0930 270 57 30 17 10 

40 LK1KRU03 4/28/2004 1050 460 40 86 220 49 

42 SM1WLL04 4/28/2004 1520 2,000 60 450 3,000 74 

43 LK1ELS04 4/28/2004 0930 400 5.7 94 15,000 98 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Hardness,

total,

calculated

(mg/L as

CaCO

3

)

Calcium,

dissolved

(mg/L)

Magnesium,

dissolved

(mg/L)

Sodium,

dissolved

(mg/L)

Percent

sodium,

in equivale

of major

cations

(percent
Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

neutralizing

capacity,

whole-water,

titration to

pH 4.5,

laboratory

(mg/L as

CaCO

3

)

Bicarbonate,

whole-water,

titration to

pH 4.5,

laboratory

(mg/L)

Carbonate,

whole-water,

titration to

pH 8.3,

laboratory

(mg/L)

Hydroxi

whole-wa

titration 

pH 10.4

laborato

(mg/L

2003

4 SS1THL03 4/21/2003 1620 56 68<1<1 

6 SS1WLD03 4/22/2003 1530 100 122<1<1 

9 TP1WLD03 4/22/2003 1330 38 46<1<1 

10 SM1WLD03 4/22/2003 1100 185 226<1<1 

11 TP1THL03 4/22/2003 0845 39 47<1<1 

12 LK1THL03 4/22/2003 0930 393 286 95<1 

18 SS3WDM03 4/24/2003 0830 119 145<1<1 

20 SS2WDM03 4/24/2003 1110 96 118<1<1 

22 SM1WDM03 4/24/2003 1405 182 222<1<1 

22 SM1WDM03 4/24/2003

11410 175 214

<1<1 

23 TP1CNC03 4/23/2003 1050 407 497<1<1 

25 SS4WDM03 4/24/2003 1630 47 57<1<1 

26 SS1CNC03 4/24/2003 1120 124 151<1<1 

27 SM1CNC03 4/23/2003 0900 136 166<1<1 

28 LK1SEL03 4/23/2003 1100 133 1611<1 

28 LK1SEL03 4/23/2003

11105 139 169

<1<1 

30 TP1ASP03 4/22/2003 1500 239 291<1<1 

31 TP1SEL03 4/23/2003 1430 24 29<1<1 

33 LK1FSC03 4/23/2003 0740 474 5628<1 

34 LK1SSK03 4/24/2003 0950 503 542 35<1 

36 LK1WWH03 4/24/2003 0810 1,870 2,280<1<1 

38 SS1KRU03 4/24/2003 1440 63 77<1<1 

39 SS2KRU03 4/24/2003 1350 32 39<1<1 

40 LK1KRU03 4/22/2003 1330 414 451 27<1 

41 TP1WSU03 4/23/2003 1250 72 88<1<1 

44 SS1ELN03 4/23/2003 1500 38 46<1<1 
2004

1 SS4WLD04 4/28/2004 0800 96 117<1<1 

1 SS4WLD04 4/28/2004

10805 96 117

<1<1 

2 SM4WLD04 4/28/2004 0900 112 89 23<1 

3 SM1THL04 4/28/2004 0800 208 222 16<1 

5 SM3WLD04 4/28/2004 1130 66 80<1<1 

7 TP2WLD04 4/28/2004 1115 63 77<1<1

8 SM2WLD04 4/28/2004 1015 298 187 87<1 

12 LK1THL03 4/28/2004 1445 1,230 939 280<1 

13 SS1TLS04 4/28/2004 1600 86 105<1<1 

14 SS1TWS04 4/26/2004 1245 131 90 34<1 

15 SS2WLD04 4/27/2004 1255 48 59<1<1 

16 SS3WLD04 4/27/2004 1155 112 137<1<1 

16 SS3WLD04 4/27/2004

11200 113 138

<1<1 

17 SS1ASP04 4/27/2004 0830 83 30 35<1 

19 SM2CNC04 4/27/2004 1420 191 2244<1 

21 TP2CNC04 4/26/2004 1555 37 45<1<1 

24 SS3CNC04 4/27/2004 1500 50 60<1<1 

27 SM1CNC03 4/28/2004 1430 280 320 11<1 

29 LK1CNC04 4/28/2004 1220 583 673 19<1 

30 TP1ASP03 4/26/2004 1435 18 22<1<1 

32 SS1GNN04 4/27/2004 1530 71 86<1<1 

35 SM1KRU04 4/27/2004 1020 508 521 48<1 

37 SS3KRU04 4/27/2004 0845 132 96 32<1 

38 SS1KRU03 4/27/2004 0930 121 67 40<1 

40 LK1KRU03 4/28/2004 1050 612 637 54<1 

42 SM1WLL04 4/28/2004 1520 876 752 156<1 

43 LK1ELS04 4/28/2004 0930 6,580 2,560 2,690<1 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Acid

neutralizing

capacity,

whole-water,

titration to

pH 4.5,

laboratory

(mg/L as

CaCO

3

)

Bicarbonate,

whole-water,

titration to

pH 4.5,

laboratory

(mg/L)

Carbonate,

whole-water,

titration to

pH 8.3,

laboratory

(mg/L)

Hydroxi

whole-wa

titration 

pH 10.4

laborato

(mg/L
Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Solids,

dissolved,

sum of

constituents

(mg/L)

suspended,

residue on

evaporation

at 105°C

(mg/L)

Aluminum,

dissolved (μg/L)

Antimon

dissolve

(μg/L)

2003

4 SS1THL03 4/21/2003 1620 776<50<1

6 SS1WLD03 4/22/2003 1530 545<5<50<1

9 TP1WLD03 4/22/2003 1330 50 11 80<1

10 SM1WLD03 4/22/2003 1100 445<5 60<1

11 TP1THL03 4/22/2003 0845 628 200<1

12 LK1THL03 4/22/2003 0930 4,0909<50<1 

18 SS3WDM03 4/24/2003 0830 2186<50<1

20 SS2WDM03 4/24/2003 1110 163<5 200<1

22 SM1WDM03 4/24/2003 1405 488 48 500<1

22 SM1WDM03 4/24/2003

1

1410 480 29 400<1

23 TP1CNC03 4/23/2003 1050 3,3406<50<1

25 SS4WDM03 4/24/2003 1630 222 118 200<1

26 SS1CNC03 4/24/2003 1120 185<5<50<1

27 SM1CNC03 4/23/2003 0900 4129<50<1

28 LK1SEL03 4/23/2003 1100 1538 200<1

28 LK1SEL03 4/23/2003

1

1105 157<5<50<1

30 TP1ASP03 4/22/2003 1500 3239<50<1

31 TP1SEL03 4/23/2003 1430 35<5<50<1

33 LK1FSC03 4/23/2003 0740 803<5<50<1

34 LK1SSK03 4/24/2003 0950 1,410 21 200<1

36 LK1WWH03 4/24/2003 0810 17,4006<50<1 

38 SS1KRU03 4/24/2003 1440 108 10<50<1

39 SS2KRU03 4/24/2003 1350 48<5<50<1

40 LK1KRU03 4/22/2003 1330 709 12 80<1

41 TP1WSU03 4/23/2003 1250 905<50<1

44 SS1ELN03 4/23/2003 1500 59<5<50<1
2004

1 SS4WLD04 4/28/2004 0800 212<5 100<1

1 SS4WLD04 4/28/2004

1

0805 214<5 70<1

2 SM4WLD04 4/28/2004 0900 1,260<5 80<1

3 SM1THL04 4/28/2004 0800 1,370 10<50<1

5 SM3WLD04 4/28/2004 1130 81<5<50<1

7 TP2WLD04 4/28/2004 1115 68<5 50<1

8 SM2WLD04 4/28/2004 1015 610 412 6,800<1 

12 LK1THL03 4/28/2004 1445 13,800 23 802 

13 SS1TLS04 4/28/2004 1600 4798 80<1

14 SS1TWS04 4/26/2004 1245 625 33 1,800<1 

15 SS2WLD04 4/27/2004 1255 71<5 60<1

16 SS3WLD04 4/27/2004 1155 309<5 60<1

16 SS3WLD04 4/27/2004

1

1200 3068 100<1

17 SS1ASP04 4/27/2004 0830 935 15<50<1

19 SM2CNC04 4/27/2004 1420 1,740<5<50<1

21 TP2CNC04 4/26/2004 1555 458 70<1

24 SS3CNC04 4/27/2004 1500 93<5<50<1

27 SM1CNC03 4/28/2004 1430 4,130 27 400<1 

29 LK1CNC04 4/28/2004 1220 2,480 10<50<1 

30 TP1ASP03 4/26/2004 1435 23 11 80<1

32 SS1GNN04 4/27/2004 1530 303<5<50<1

35 SM1KRU04 4/27/2004 1020 934 23 200<1

37 SS3KRU04 4/27/2004 0845 251 16 1,300<1

38 SS1KRU03 4/27/2004 0930 442 19 200<1

40 LK1KRU03 4/28/2004 1050 1,060 50 500<1

42 SM1WLL04 4/28/2004 1520 11,100 194 2,5004 

43 LK1ELS04 4/28/2004 0930 40,700 16<50<1 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Solids,

dissolved,

sum of

constituents

(mg/L)

Solids,

suspended,

residue on

evaporation

at 105°C

(mg/L)

Aluminum,

dissolved (μg/L)

Antimon

dissolve

(μg/L)
site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Beryllium,

dissolved

(μg/L)

Boron,

dissolved

(μg/L)

Cadmium,

dissolved

(μg/L)

Chromium,

dissolved

(μg/L)

Copp

disso

(μg

2003

4 SS1THL03 4/21/2003 1620 <1 60 <1 <1 <1 

6 SS1WLD03 4/22/2003 1530 <1 90 <1 <1 <1 

9 TP1WLD03 4/22/2003 1330 <1 <50 <1 <1 <1 

10 SM1WLD03 4/22/2003 1100 <1 80 <1 <1 <1 

11 TP1THL03 4/22/2003 0845 <1 50 <1 <1 <1 

12 LK1THL03 4/22/2003 0930 <1 380 <1 <1 <1 

18 SS3WDM03 4/24/2003 0830 <1 80 <1 <1 2 

20 SS2WDM03 4/24/2003 1110 <1 100 <1 <1 <1 

22 SM1WDM03 4/24/2003 1405 <1 60 <1 <1 <1 

22 SM1WDM03 4/24/2003 11410 <1 60 <1 <1 <1 

23 TP1CNC03 4/23/2003 1050 <1 310 <1 3 1 

25 SS4WDM03 4/24/2003 1630 <1 100 <1 <1 1 

26 SS1CNC03 4/24/2003 1120 <1 160 <1 <1 2 

27 SM1CNC03 4/23/2003 0900 <1 110 <1 <1 <1 

28 LK1SEL03 4/23/2003 1100 <1 90 <1 <1 <1 

28 LK1SEL03 4/23/2003 11105 <1 70 <1 3 <1 

30 TP1ASP03 4/22/2003 1500 <1 60 <1 <1 <1 

31 TP1SEL03 4/23/2003 1430 <1 60 <1 <1 <1 

33 LK1FSC03 4/23/2003 0740 <1 <50 <1 <1 <1 

34 LK1SSK03 4/24/2003 0950 <1 310 <1 <1 2 

36 LK1WWH03 4/24/2003 0810 <1 400 <1 <1 15 

38 SS1KRU03 4/24/2003 1440 <1 90 <1 <1 2 

39 SS2KRU03 4/24/2003 1350 <1 70 <1 <1 <1 

40 LK1KRU03 4/22/2003 1330 <1 170 <1 <1 <1 

41 TP1WSU03 4/23/2003 1250 <1 U <1 <1 2 

44 SS1ELN03 4/23/2003 1500 <1 60 <1 <1 <1 
2004

1 SS4WLD04 4/28/2004 0800 <1 50 <1 <1 <1 

1 SS4WLD04 4/28/2004 10805 <1 60 <1 <1 <1 

2 SM4WLD04 4/28/2004 0900 <1 60 <1 <1 2 

3 SM1THL04 4/28/2004 0800 <1 70 <1 <1 M 

5 SM3WLD04 4/28/2004 1130 <1 50 <1 <1 <1 

7 TP2WLD04 4/28/2004 1115 <1 60 <1 <1 1 

8 SM2WLD04 4/28/2004 1015 <1 70 <1 9 10 

12 LK1THL03 4/28/2004 1445 <1 1,300 <1 1 50 

13 SS1TLS04 4/28/2004 1600 <1 90 <1 <1 1 

14 SS1TWS04 4/26/2004 1245 <1 190 <1 3 3 

15 SS2WLD04 4/27/2004 1255 <1 70 <1 <1 <1 

16 SS3WLD04 4/27/2004 1155 <1 60 <1 <1 <1 

16 SS3WLD04 4/27/2004 11200 <1 60 <1 <1 1 

17 SS1ASP04 4/27/2004 0830 <1 <50 <1 <1 2 

19 SM2CNC04 4/27/2004 1420 <1 90 <1 <1 3 

21 TP2CNC04 4/26/2004 1555 <1 50 <1 <1 1 

24 SS3CNC04 4/27/2004 1500 <1 50 <1 <1 <1 

27 SM1CNC03 4/28/2004 1430 <1 260 <1 1 10 

29 LK1CNC04 4/28/2004 1220 <1 290 <1 <1 10 

30 TP1ASP03 4/26/2004 1435 <1 U <1 <1 1 

32 SS1GNN04 4/27/2004 1530 <1 70 <1 <1 1 

35 SM1KRU04 4/27/2004 1020 <1 190 <1 <1 5 

37 SS3KRU04 4/27/2004 0845 <1 110 <1 2 3 

38 SS1KRU03 4/27/2004 0930 <1 190 <1 <1 2 

40 LK1KRU03 4/28/2004 1050 <1 190 <1 1 6 

42 SM1WLL04 4/28/2004 1520 <1 1,100 <1 5 70 

43 LK1ELS04 4/28/2004 0930 <1 2,500 <1 50 590 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Beryllium,

dissolved

(μg/L)

Boron,

dissolved

(μg/L)

Cadmium,

dissolved

(μg/L)

Chromium,

dissolved

(μg/L)

Copp

disso

(μg
site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Manganese,

dissolved

(μg/L)

Nickel,

dissolved

(μg/L)

Selenium,

dissolved

(μg/L)

Silver,

dissolved

(μg/L)

2003

4 SS1THL03 4/21/2003 1620 <10 1 <1 <1 

6 SS1WLD03 4/22/2003 1530 70 2 <1 <1 

9 TP1WLD03 4/22/2003 1330 <10 <1 <1 <1 

10 SM1WLD03 4/22/2003 1100 110 2 <1 <1 

11 TP1THL03 4/22/2003 0845 <10 <1 <1 <1 

12 LK1THL03 4/22/2003 0930 <10 <1 <1 <1 

18 SS3WDM03 4/24/2003 0830 180 1 <1 <1 

20 SS2WDM03 4/24/2003 1110 40 1 <1 <1 

22 SM1WDM03 4/24/2003 1405 210 3 <1 <1 

22 SM1WDM03 4/24/2003 11410 200 3 <1 <1 

23 TP1CNC03 4/23/2003 1050 <10 11 2 <1 

25 SS4WDM03 4/24/2003 1630 40 2 <1 <1 

26 SS1CNC03 4/24/2003 1120 <10 2 <1 <1 

27 SM1CNC03 4/23/2003 0900 20 2 <1 <1 

28 LK1SEL03 4/23/2003 1100 50 1 <1 <1 

28 LK1SEL03 4/23/2003 11105 20 1 <1 <1 

30 TP1ASP03 4/22/2003 1500 20 2 2 <1 

31 TP1SEL03 4/23/2003 1430 <10 <1 <1 <1 

33 LK1FSC03 4/23/2003 0740 <10 3 <1 <1 

34 LK1SSK03 4/24/2003 0950 <10 2 1 <1 

36 LK1WWH03 4/24/2003 0810 <10 20 <1 <1 

38 SS1KRU03 4/24/2003 1440 180 <1 <1 <1 

39 SS2KRU03 4/24/2003 1350 <10 <1 <1 <1 

40 LK1KRU03 4/22/2003 1330 <10 1 <1 <1 

41 TP1WSU03 4/23/2003 1250 10 <1 <1 <1 

44 SS1ELN03 4/23/2003 1500 <10 <1 <1 <1 
2004

1 SS4WLD04 4/28/2004 0800 70 1 1 <1 

1 SS4WLD04 4/28/2004 10805 60 2 <1 <1 

2 SM4WLD04 4/28/2004 0900 60 5 3 <1 

3 SM1THL04 4/28/2004 0800 70 M 4 <1 

5 SM3WLD04 4/28/2004 1130 40 1 <1 <1 

7 TP2WLD04 4/28/2004 1115 30 1 <1 <1 

8 SM2WLD04 4/28/2004 1015 340 12 4 <1 

12 LK1THL03 4/28/2004 1445 30 3 23 <1 

13 SS1TLS04 4/28/2004 1600 40 2 5 <1 

14 SS1TWS04 4/26/2004 1245 160 7 13 <1 

15 SS2WLD04 4/27/2004 1255 30 1 1 <1 

16 SS3WLD04 4/27/2004 1155 20 2 <1 <1 

16 SS3WLD04 4/27/2004 11200 30 2 <1 <1 

17 SS1ASP04 4/27/2004 0830 20 6 5 <1 

19 SM2CNC04 4/27/2004 1420 40 5 10 <1 

21 TP2CNC04 4/26/2004 1555 20 <1 3 <1 

24 SS3CNC04 4/27/2004 1500 10 <1 6 <1 

27 SM1CNC03 4/28/2004 1430 620 16 11 <1 

29 LK1CNC04 4/28/2004 1220 50 2 8 <1 

30 TP1ASP03 4/26/2004 1435 10 <1 1 <1 

32 SS1GNN04 4/27/2004 1530 <10 2 <1 <1 

35 SM1KRU04 4/27/2004 1020 70 2 3 <1 

37 SS3KRU04 4/27/2004 0845 170 4 <1 <1 

38 SS1KRU03 4/27/2004 0930 210 5 <1 <1 

40 LK1KRU03 4/28/2004 1050 130 3 5 <1 

42 SM1WLL04 4/28/2004 1520 200 14 33 <1 

43 LK1ELS04 4/28/2004 0930 30 <1 28 <1 

1Quality-assurance/quality-control replicate sample.

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Manganese,

dissolved

(μg/L)

Nickel,

dissolved

(μg/L)

Selenium,

dissolved

(μg/L)

Silver,

dissolved

(μg/L)
site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Methylmercury,

dissolved

(ng/L)

Methylmercury,

suspended

(ng/L)

Methylmercury,

whole-water

(ng/L)

Inorgani

mercury

dissolve

(ng/L)

2003

4 SS1THL03 4/21/2003 1620 0.58 0.07 0.65 5.58 

6 SS1WLD03 4/22/2003 1530 .75 .10 .85 3.97 

9 TP1WLD03 4/22/2003 1330 .43 .05 .48 4.12 

10 SM1WLD03 4/22/2003 1100 .52 .06 .58 .86 

11 TP1THL03 4/22/2003 0845 .54 .04 .58 7.90 

12 LK1THL03 4/22/2003 0930 .14 .11 .25 .56 

18 SS3WDM03 4/24/2003 0830 5.76 .07 5.80 3.71 

20 SS2WDM03 4/24/2003 1110 E5.91 .22 E6.13 E5.29 

22 SM1WDM03 4/24/2003 1405 .86 .38 1.24 1.52 

22 SM1WDM03 4/24/2003 11410 1.07 .14 1.21 .85 

23 TP1CNC03 4/23/2003 1050 .25 .06 .31 1.42 

25 SS4WDM03 4/24/2003 1630 1.28 .05 1.33 5.14 

26 SS1CNC03 4/24/2003 1120 .44 -- -- 6.62 

27 SM1CNC03 4/23/2003 0900 E2.16 .08 E2.24 E5.23 

28 LK1SEL03 4/23/2003 1100 .18 .03 .21 .54 

28 LK1SEL03 4/23/2003 11105 .12 -- -- .68 

30 TP1ASP03 4/22/2003 1500 .90 .18 1.07 2.16 

31 TP1SEL03 4/23/2003 1430 .40 .04 .47 5.60 

33 LK1FSC03 4/23/2003 0740 .05 <.03 E.05 .72 

34 LK1SSK03 4/24/2003 0950 .21 .05 .26 .80 

36 LK1WWH03 4/24/2003 0810 .04 .03 .07 1.70 

38 SS1KRU03 4/24/2003 1440 E9.16 .40 E9.56 E5.44 

39 SS2KRU03 4/24/2003 1350 .53 .14 .67 4.79 

40 LK1KRU03 4/22/2003 1330 .10 .03 .13 .68 

41 TP1WSU03 4/23/2003 1250 .61 .07 .68 3.01 

44 SS1ELN03 4/23/2003 1500 .59 .04 .63 7.12 
2004

1 SS4WLD04 4/28/2004 0800 0.10 <0.03 E0.10 4.20 

1 SS4WLD04 4/28/2004 10805 .09 .04 .13 4.38 

2 SM4WLD04 4/28/2004 0900 .19 .03 .22 1.39 

3 SM1THL04 4/28/2004 0800 .26 <.03 E.26 .61 

5 SM3WLD04 4/28/2004 1130 1.22 .03 1.25 3.94 

7 TP2WLD04 4/28/2004 1115 .28 <.03 E.28 5.96 

8 SM2WLD04 4/28/2004 1015 .15 .30 .45 2.67 

12 LK1THL03 4/28/2004 1445 .07 .10 .17 .53 

13 SS1TLS04 4/28/2004 1600 1.62 .06 1.68 2.77 

14 SS1TWS04 4/26/2004 1245 <.04 .27 E.27 E3.84 

15 SS2WLD04 4/27/2004 1255 <.04 .11 E.11 E6.69 

16 SS3WLD04 4/27/2004 1155 1.57 .03 1.60 2.81 

16 SS3WLD04 4/27/2004 11200 1.19 .14 1.33 3.29 

17 SS1ASP04 4/27/2004 0830 .06 .04 .10 2.64 

19 SM2CNC04 4/27/2004 1420 .17 .07 .24 1.54 

21 TP2CNC04 4/26/2004 1555 .29 .08 .37 7.31 

24 SS3CNC04 4/27/2004 1500 1.19 <.03 E1.19 4.79 

27 SM1CNC03 4/28/2004 1430 .69 .21 .90 3.30 

29 LK1CNC04 4/28/2004 1220 .29 .06 .35 1.22 

30 TP1ASP03 4/26/2004 1435 .08 .03 .11 3.13 

32 SS1GNN04 4/27/2004 1530 .50 .10 .60 3.53 

35 SM1KRU04 4/27/2004 1020 .11 .06 .17 1.25 

37 SS3KRU04 4/27/2004 0845 .10 .07 .17 2.82 

38 SS1KRU03 4/27/2004 0930 .22 .16 .38 3.50 

40 LK1KRU03 4/28/2004 1050 .07 .07 .14 .73 

42 SM1WLL04 4/28/2004 1520 .06 .24 .30 2.58 

43 LK1ELS04 4/28/2004 0930 <.04 .03 <.04 E2.80 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Methylmercury,

dissolved

(ng/L)

Methylmercury,

suspended

(ng/L)

Methylmercury,

whole-water

(ng/L)

Inorgani

mercury

dissolve

(ng/L)
site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Total

mercury,

dissolved

(ng/L)

Total

mercury,

suspended

(ng/L)

Total

mercury,

whole-water

(ng/L)

whole-water

methylmercury

to whole-water

total mercury

2003

4 SS1THL03 4/21/2003 1620 6.16 0.52 6.68 0.097 

6 SS1WLD03 4/22/2003 1530 4.72 .68 5.40 .157 

9 TP1WLD03 4/22/2003 1330 4.55 .28 4.83 .099 

10 SM1WLD03 4/22/2003 1100 1.38 .50 1.88 .309 

11 TP1THL03 4/22/2003 0845 8.44 .44 8.88 .065 

12 LK1THL03 4/22/2003 0930 .70 .55 1.25 .200 

18 SS3WDM03 4/24/2003 0830 9.47 .72 10.6 .547 

20 SS2WDM03 4/24/2003 1110 11.20 .38 11.6 E.528 

22 SM1WDM03 4/24/2003 1405 2.38 E4.61 E6.99 E.180 

22 SM1WDM03 4/24/2003 11410 1.92 1.68 3.60 .336 

23 TP1CNC03 4/23/2003 1050 1.67 .45 2.12 .146 

25 SS4WDM03 4/24/2003 1630 6.42 .38 6.80 .196 

26 SS1CNC03 4/24/2003 1120 7.06 .86 7.92 -- 

27 SM1CNC03 4/23/2003 0900 7.39 .35 7.74 E.289 

28 LK1SEL03 4/23/2003 1100 .72 .59 1.31 .160 

28 LK1SEL03 4/23/2003 11105 .80 .32 1.12 -- 

30 TP1ASP03 4/22/2003 1500 3.06 1.14 4.20 .255 

31 TP1SEL03 4/23/2003 1430 6.00 1.10 6.72 .070 

33 LK1FSC03 4/23/2003 0740 .77 .23 1.00 E.060 

34 LK1SSK03 4/24/2003 0950 1.01 4.27 5.28 .049 

36 LK1WWH03 4/24/2003 0810 1.74 .98 2.71 .026 

38 SS1KRU03 4/24/2003 1440 14.60 2.57 17.2 E.556 

39 SS2KRU03 4/24/2003 1350 5.32 .41 5.73 .117 

40 LK1KRU03 4/22/2003 1330 .78 1.07 1.85 .070 

41 TP1WSU03 4/23/2003 1250 3.62 .36 3.98 .171 

44 SS1ELN03 4/23/2003 1500 7.71 .68 8.39 .075 
2004

1 SS4WLD04 4/28/2004 0800 4.30 <0.10 E4.30 E0.023 

1 SS4WLD04 4/28/2004 10805 4.47 <.10 E4.47 E.029 

2 SM4WLD04 4/28/2004 0900 1.58 <.10 E1.58 E.139 

3 SM1THL04 4/28/2004 0800 .87 <.10 E.87 E.299 

5 SM3WLD04 4/28/2004 1130 5.16 E.14 E5.30 E.236 

7 TP2WLD04 4/28/2004 1115 6.24 E.24 E6.48 E.043 

8 SM2WLD04 4/28/2004 1015 2.82 5.85 8.67 .052 

12 LK1THL03 4/28/2004 1445 .60 1.99 2.59 .066 

13 SS1TLS04 4/28/2004 1600 4.39 E.35 E4.74 E.354 

14 SS1TWS04 4/26/2004 1245 3.84 2.01 5.85 E.046 

15 SS2WLD04 4/27/2004 1255 6.69 E.54 E7.23 E.015 

16 SS3WLD04 4/27/2004 1155 4.38 E.37 E4.75 E.337 

16 SS3WLD04 4/27/2004 11200 4.48 E.26 E4.74 E.281 

17 SS1ASP04 4/27/2004 0830 2.70 E1.17 E3.87 E.026 

19 SM2CNC04 4/27/2004 1420 1.71 E.89 E2.60 E.092 

21 TP2CNC04 4/26/2004 1555 7.60 E.75 E8.35 E.044 

24 SS3CNC04 4/27/2004 1500 5.98 <.10 E5.98 E.199 

27 SM1CNC03 4/28/2004 1430 3.99 E1.31 E5.30 E.170 

29 LK1CNC04 4/28/2004 1220 1.51 E.62 E2.14 E.166 

30 TP1ASP03 4/26/2004 1435 3.21 E.68 E3.89 E.028 

32 SS1GNN04 4/27/2004 1530 4.03 <.10 E4.03 E.149 

35 SM1KRU04 4/27/2004 1020 1.36 E.24 E1.60 E.106 

37 SS3KRU04 4/27/2004 0845 2.92 E.82 E3.74 E.045 

38 SS1KRU03 4/27/2004 0930 3.72 E.57 E4.29 E.089 

40 LK1KRU03 4/28/2004 1050 .80 E1.03 E1.83 E.077 

42 SM1WLL04 4/28/2004 1520 2.64 9.37 12.0 .025 

43 LK1ELS04 4/28/2004 0930 2.80 E.72 E3.52 E.006 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Total

mercury,

dissolved

(ng/L)

Total

mercury,

suspended

(ng/L)

Total

mercury,

whole-water

(ng/L)

Ratio of

whole-water

methylmercury

to whole-water

total mercury
site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Methylmercury,

sediment

(ng/g)

Total

mercury,

sediment

(ng/g)

Ratio of

methylmercury

to total mercury,

sediment

2003

4 SS1THL03 4/21/2003 1620 0.51 53.9 0.009 

6 SS1WLD03 4/22/2003 1530 .10 30.2 .007 

9 TP1WLD03 4/22/2003 1330 .61 40.7 .015 

10 SM1WLD03 4/22/2003 1100 .08 51.2 .004 

11 TP1THL03 4/22/2003 0845 .14 34.8 .006 

12 LK1THL03 4/22/2003 0930 .05 18.2 .011 

18 SS3WDM03 4/24/2003 0830 .58 60.3 .010 

20 SS2WDM03 4/24/2003 1110 .75 48.4 .015 

22 SM1WDM03 4/24/2003 1405 1.17 60.8 .019 

22 SM1WDM03 4/24/2003

11410 1.02 68.1 .015 

23 TP1CNC03 4/23/2003 1050 .26 28.0 .007 

25 SS4WDM03 4/24/2003 1630 2.05 50.5 .041 

26 SS1CNC03 4/24/2003 1120 3.28 55.3 .059 

27 SM1CNC03 4/23/2003 0900 .25 40.8 .005 

28 LK1SEL03 4/23/2003 1100 .60 59.7 .010 

28 LK1SEL03 4/23/2003

11105 .71 47.1 .015 

30 TP1ASP03 4/22/2003 1500 1.28 73.0 .018 

31 TP1SEL03 4/23/2003 1430 .66 25.7 .026 

33 LK1FSC03 4/23/2003 0740 .53 49.9 .011 

34 LK1SSK03 4/24/2003 0950 .07 20.1 .010 

36 LK1WWH03 4/24/2003 0810 .03 6.77 .030 

38 SS1KRU03 4/24/2003 1440 1.12 38.4 .029 

39 SS2KRU03 4/24/2003 1350 .84 58.5 .014 

40 LK1KRU03 4/22/2003 1330 .08 23.3 .009 

41 TP1WSU03 4/23/2003 1250 .16 27.5 .007 

44 SS1ELN03 4/23/2003 1500 .58 35.9 .016 
2004

1 SS4WLD04 4/28/2004 0800 2.57 48.6 0.053 

1 SS4WLD04 4/28/2004 10805 4.72 64.7 .073 

2 SM4WLD04 4/28/2004 0900 <.39 59.8 .003 

3 SM1THL04 4/28/2004 0800 <.31 42.4 .005 

5 SM3WLD04 4/28/2004 1130 .34 38.8 .005 

7 TP2WLD04 4/28/2004 1115 1.30 99.0 .013 

8 SM2WLD04 4/28/2004 1015 .53 43.2 .012 

12 LK1THL03 4/28/2004 1445 <.11 8.54 .023 

13 SS1TLS04 4/28/2004 1600 1.05 38.3 .027 

14 SS1TWS04 4/26/2004 1245 <.22 22.7 .009 

15 SS2WLD04 4/27/2004 1255 .43 22.0 .020 

16 SS3WLD04 4/27/2004 1155 2.07 34.4 .060 

16 SS3WLD04 4/27/2004 11200 1.64 18.8 .087 

17 SS1ASP04 4/27/2004 0830 1.13 58.0 .019 

19 SM2CNC04 4/27/2004 1420 2.54 58.9 .043 

21 TP2CNC04 4/26/2004 1555 .46 51.2 .009 

24 SS3CNC04 4/27/2004 1500 4.16 89.4 .047 

27 SM1CNC03 4/28/2004 1430 .95 54.4 .017 

29 LK1CNC04 4/28/2004 1220 <.14 11.2 .017 

30 TP1ASP03 4/26/2004 1435 1.82 71.3 .026 

32 SS1GNN04 4/27/2004 1530 1.77 68.6 .026 

35 SM1KRU04 4/27/2004 1020 .60 41.6 .014 

37 SS3KRU04 4/27/2004 0845 1.58 41.6 .038 

38 SS1KRU03 4/27/2004 0930 3.36 40.0 .084 

40 LK1KRU03 4/28/2004 1050 .50 26.9 .019 

42 SM1WLL04 4/28/2004 1520 <.19 30.7 .007 

43 LK1ELS04 4/28/2004 0930 <.14 8.66 .023 

1Quality-assurance/quality-control replicate sample.

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Methylmercury,

sediment

(ng/g)

Total

mercury,

sediment

(ng/g)

Ratio of

methylmercury

to total mercury,

sediment
Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Methylmercury,

dissolved

(ng/L)

Methylmercury,

suspended

(ng/L)

Total

mercury,

dissolved

(ng/L)

To

mer

suspe

(ng

Mercury and organic carbon

(U.S. Geological Survey Wisconsin Water Science Center Mercury Laboratory, Madison, Wisconsin)

2003

18 SS3WDM03 4/24/2003 0825 <0.04 <0.027 0.50 0.1

33 LK1FSC03 4/23/2003 0735 <.04 <.027 .09 <.0

2004

14 SS1TWS04 4/26/2004 1250 <0.04 <0.027 0.48 <0.0

17 SS1ASP04 4/27/2004 0835 <.04 <.027 .34 <.0

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Specific

conductance,

laboratory

(μS/cm)

Calcium,

dissolved

(mg/L)

Magnesium,

dissolved

(mg/L)

Potassium,

dissolved

(mg/L)

Sodium,

dissolved

(mg/L)

AN

who

wat

titratio

pH 4

labora

(mg/L 

CaC

Inorganic properties and constituents

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 1 <2.00 <1.00 <1.00 <3.00 2 

33 LK1FSC03 4/23/2003 0735 1 <2.00 <1.00 <1.00 <3.00 2 

2004

14 SS1TWS04 4/26/2004 1250 3 <2.00 <1.00 <1.00 <3.00 5 

17 SS1ASP04 4/27/2004 0835 2 <2.00 <1.00 <1.00 <3.00 4 
detected]

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Hydroxide,

wholewater,

titration to

pH 10.4,

laboratory

(mg/L)

Sulfate,

dissolved

(mg/L)

Chloride,

dissolved

(mg/L)

Solids,

dissolved,

sum of

constituents

(mg/L)

Solids,

suspended,

residue on

evaporation

at 105°C

(mg/L)

Al

di

Inorganic properties and constituents, Continued

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 <1 1.3 <0.3 12 <5.00 

33 LK1FSC03 4/23/2003 0735 <1 1 <.3 11 <5.00 

2004

14 SS1TWS04 4/26/2004 1250 <1 0.4 <0.3 13 <5.00 

17 SS1ASP04 4/27/2004 0835 <1 <.3 <.3 12 <5.00 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Barium,

dissolved

(μg/L)

Beryllium,

dissolved

(μg/L)

Boron,

dissolved

(μg/L))

Cadmium,

dissolved

(μg/L)

Chromium,

dissolved

(μg/L)

C

di

Inorganic properties and constituents, Continued

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 <1.0 <1 U <1 <1 

33 LK1FSC03 4/23/2003 0735 <1.0 <1 <50 <1 <1 

2004

14 SS1TWS04 4/26/2004 1250 8.1 <1 <50 <1 <1 

17 SS1ASP04 4/27/2004 0835 4.2 <1 <50 <1 <1 
Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Manganese,

dissolved

(μg/L)

Nickel,

dissolved

(μg/L)

Selenium,

dissolved

(μg/L)

Silver,

dissolve

(μg/L)

Inorganic properties and constituents, Continued

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 <10 <1 <1 <1 

33 LK1FSC03 4/23/2003 0735 <10 <1 <1 <1 

2004

14 SS1TWS04 4/26/2004 1250 <10 <1 <1 <1 

17 SS1ASP04 4/27/2004 0835 <10 <1 4 <1 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Specific

conductance,

laboratory

(μS/cm)

Calcium,

dissolved

(mg/L)

Magnesium,

dissolved

(mg/L)

Potassium,

dissolved

(mg/L)

Sodium,

dissolved

(mg/L)

Inorganic properties, major ions, and suspended solids

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 1 <2.00 <1.00 <1.00 <3.00 

33 LK1FSC03 4/23/2003 0735 1 <2.00 <1.00 <1.00 <3.00 

2004

14 SS1TWS04 4/26/2004 1250 3 <2.00 <1.00 <1.00 <3.00 

17 SS1ASP04 4/27/2004 0835 2 <2.00 <1.00 <1.00 <3.00 
detected]

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Carbonate,

wholewater,

titration to

pH 8.3,

laboratory

(mg/L)

Hydroxide,

wholewater,

titration to

pH 10.4,

laboratory

(mg/L)

Sulfate,

dissolved

(mg/L)

Chloride,

dissolved

(mg/L)

Inorganic properties, major ions, and suspended solids, Continued

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 <1 <1 1.3 <0.3 

33 LK1FSC03 4/23/2003 0735 <1 <1 1.0 <.3 

2004

14 SS1TWS04 4/26/2004 1250 <1 <1 0.4 <0.3 

17 SS1ASP04 4/27/2004 0835 <1 <1 <.3 <.3 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Aluminum,

dissolved

(μg/L)

Antimony,

dissolved

(μg/L)

Arsenic,

dissolved

(μg/L)

Barium,

dissolved

(μg/L)

Trace elements

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 <50 <1 <1.0 <1.0 

33 LK1FSC03 4/23/2003 0735 <50 <1 <1.0 <1.0 

2004

14 SS1TWS04 4/26/2004 1250 <50 <1 <1.0 8.1 

17 SS1ASP04 4/27/2004 0835 <50 <1 1.3 4.2 
Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Cadmium,

dissolved

(μg/L)

Chromium,

dissolved

(μg/L)

Copper,

dissolved

(μg/L)

Iron,

dissolved

(μg/L)

Trace elements, Continued

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 <1 <1 <1 <10 

33 LK1FSC03 4/23/2003 0735 <1 <1 <1 <10 

2004

14 SS1TWS04 4/26/2004 1250 <1 <1 <1 10 

17 SS1ASP04 4/27/2004 0835 <1 <1 <1 10 

Sampling

site

number

(see

figure 1)

Sampling

site

name

Date of

sample

collection

Time of

sample

collection

Nickel,

dissolved

(μg/L)

Selenium,

dissolved

(μg/L)

Silver,

dissolved

(μg/L)

Trace elements, Continued

(North Dakota Department of Health Laboratory, Bismarck, North Dakota)

2003

18 SS3WDM03 4/24/2003 0825 <1 <1 <1 

33 LK1FSC03 4/23/2003 0735 <1 <1 <1 

2004

14 SS1TWS04 4/26/2004 1250 <1 <1 <1 

17 SS1ASP04 4/27/2004 0835 <1 4 <1 
Specific

conductance,

laboratory

Calcium,

dissolved

Magnesium,

dissolved

Potassium,

dissolved

Sodium,

dissolved

Number of replicate pairs with complete

analytical results for given parameter

4 4 4 4 4 

Median relative standard deviation,

in percent, for all replicate pairs

.7 .7 .6 .4 2.0 

Carbonate,

whole-water,

titration

to pH 8.3,

laboratory

Hydroxide,

whole-water,

titration

to pH 10.4,

laboratory

Sulfate,

dissolved

Chloride,

dissolved

Solids,

dissolved,

sum of

constituent

Number of replicate pairs with complete

analytical results for given parameter

4 4 4 4 4 

Median relative standard deviation,

in percent, for all replicate pairs

0 0 1.7 .8 .9 

Antimony,

dissolved

Arsenic,

dissolved

Barium,

dissolved

Beryllium,

dissolved

Boron,

dissolved

Number of replicate pairs with complete

analytical results for given parameter

4 4 4 4 4 

Median relative standard deviation,

in percent, for all replicate pairs

0 6.1 7.8 0 6.4 

Copper,

dissolved

Iron,

dissolved

Lead,

dissolved

Manganese,

dissolved

Nickel,

dissolved

Number of replicate pairs with complete

analytical results for given parameter

4 4 4 4 4 

Median relative standard deviation,

in percent, for all replicate pairs

0 26.2 0 19.6 9.0 
Thallium,

dissolved

Zinc,

dissolved

Methylmercury,

dissolved

Methylmercury,

suspended

Methylmercu

whole-wate

Number of replicate pairs with complete

analytical results for given parameter

4 4 4 3 3 

Median relative standard deviation,

in percent, for all replicate pairs

0 14.1 17.4 64.6 7.4 

Total

mercury,

whole-water

Organic

carbon,

dissolved

Organic

carbon,

whole-water

Methylmercury,

sediment

Total

mercury,

sediment

Number of replicate pairs with complete

analytical results for given parameter

4 4 4 4 4 

Median relative standard deviation,

in percent, for all replicate pairs

6.9 .8 1.2 14.1 18.4