Prepared in cooperation with Turtle Mountain Band of Chippewa Indians

Assessment of Groundwater Quality Data for the Turtle 

Mountain Indian Reservation, Rolette County, North Dakota, 

1970–2012

Data Series 732

U.S. Department of the Interior

U.S. Geological Survey

Assessment of Groundwater Quality Data 

for the Turtle Mountain Indian Reservation, 

Rolette County, North Dakota, 1970–2012

By Robert F. Lundgren and Kevin C. Vining

Prepared in cooperation with Turtle Mountain Band of Chippewa Indians

Data Series 732

U.S. Department of the Interior

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

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2013

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Suggested citation:

Lundgren, R.F. and Vining, K.C., 2013, Assessment of groundwater quality data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota: U.S. Geological Survey Data Series 732, 17 p. and supplements.
iii

Contents

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

Introduction.....................................................................................................................................................1

Purpose and Scope ..............................................................................................................................1

Previous Studies ...................................................................................................................................1

Data Sources..................................................................................................................................................4

Physical Setting of the Study Area .............................................................................................................5

Aquifers ..................................................................................................................................................5

Land Use.................................................................................................................................................5

Assessment of Groundwater Levels...........................................................................................................6

Assessment of Groundwater Quality..........................................................................................................6

Fox Hills and Hell Creek Aquifers.......................................................................................................6

Rolla Aquifer..........................................................................................................................................7

Shell Valley Aquifer ..............................................................................................................................7

Implications...................................................................................................................................................14

Summary........................................................................................................................................................14

References Cited..........................................................................................................................................14

Supplements.................................................................................................................................................17

Figures

1. Maps showing location of the Turtle Mountain Indian Reservation and

groundwater measuring wells in major aquifers and Shell Valley aquifer, 

Rolette County, North Dakota .....................................................................................................2

2. Graph showing annual water withdrawals from the Shell Valley aquifer, 

1981 through 2011 .........................................................................................................................6

3. Graphs showing annual water levels near Rolette, Thorn, and Shell Valley

production wells, 1981 through 2011 .........................................................................................7

4. Graphs showing groundwater concentrations from North Dakota State Water

Commission wells in the Shell Valley aquifer for selected constituents that

exceeded the U.S. Environmental Protection Agency secondary maximum

contaminant levels .....................................................................................................................12

5. Graphs showing groundwater concentrations from U.S. Geological Survey 

wells in the Shell Valley aquifer for selected constituents that exceeded the 

U.S. Environmental Protection Agency secondary maximum contaminant levels..........13
iv

Tables

1. Sources of groundwater-quality data avaliable, 1970 through 2012....................................4

2. Annual acreages of major crops planted in Rolette County, North Dakota, 

1997 through 2011 .........................................................................................................................5

3. Locations of North Dakota State Water Commision groundwater sampling 

wells in the Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers, Rolette 

County, North Dakota...................................................................................................................8

4. Locations of U.S. Geological Survey groundwater sampling wells in the 

Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers, Rolette County, 

North Dakota ...............................................................................................................................10

Supplements

1. Water-quality data available in the North Dakota State Water Commission 

database for the Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers, 

1970 through 2012 .......................................................................................................................17

2. Water-quality data available in the U.S. Geological Survey database for the 

Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers, 1970 through 2012.........................17

Conversion Factors and Datum

Inch/Pound to SI

Multiply By To obtain

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

acre 4,047 square meter (m2)

square foot (ft2) 929.0 square centimeter (cm2)

square foot (ft2) 0.09290 square meter (m2)

square mile (mi2) 2.590 square kilometer (km2) 

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

 °F= (1.8×°C) +32

All lake levels and elevations used in this report are referenced to the National Geodetic 

Vertical Datum (NGVD) of 1929.

Elevation, as used in this report, refers to distance above the vertical datum. 

Specific conductance is given in microsiemens per centimeter at 25 degrees Celsius (μS/cm at 

25 °C).

Concentrations of chemical constituents in water are given either in milligrams per liter (mg/L) 

or micrograms per liter (μg/L).
Assessment of Groundwater Quality Data for the Turtle 

Mountain Indian Reservation, Rolette County, North 

Dakota, 1970–2012

By Robert F. Lundgren and Kevin C. Vining

Abstract

The Turtle Mountain Indian Reservation relies on 

groundwater supplies to meet the demands of community and 

economic needs. The U.S. Geological Survey, in cooperation 

with the Turtle Mountain Band of Chippewa Indians, examined historical groundwater-level and groundwater-quality 

data for the Fox Hills, Hell Creek, Rolla, and Shell Valley 

aquifers. The two main sources of water-quality data for 

groundwater were the U.S. Geological Survey National Water 

Information System database and the North Dakota State 

Water Commission database. Data included major ions, trace 

elements, nutrients, field properties, and physical properties.

The Fox Hills and Hell Creek aquifers had few groundwater water-quality data. The lack of data limits any detailed 

assessments that can be made about these aquifers. Data for 

the Rolla aquifer exist from 1978 through 1980 only. The concentrations of some water-quality constituents exceeded the 

U.S. Environmental Protection Agency secondary maximum 

contaminant levels. No samples were analyzed for pesticides 

and hydrocarbons.

Numerous water-quality samples have been obtained 

from the Shell Valley aquifer. About one-half of the water 

samples from the Shell Valley aquifer had concentrations of 

iron, manganese, sulfate, and dissolved solids that exceeded 

the U.S. Environmental Protection Agency secondary maximum contaminant levels. Overall, the data did not indicate 

obvious patterns in concentrations.

Introduction

The Turtle Mountain Indian Reservation, located in 

northern Rolette County, North Dakota (fig. 1A), relies on 

groundwater supplies to meet the demands of community and 

economic needs. To maintain high-quality water supplies, 

monitoring of the groundwater resources is necessary. Various 

entities have monitored groundwater quality from many locations to assist reservation agencies in making decisions about 

water distribution and use. Although considerable amounts of 

groundwater-level and water-quality data have been collected, 

much of the data reside in Federal, State, and tribal databases, 

and have not been consolidated or assessed.

To assist the Turtle Mountain Indian Reservation with 

groundwater data and investigations, the U.S. Geological 

Survey (USGS), in cooperation with the Turtle Mountain Band 

of Chippewa Indians, examined historical groundwater-level 

and groundwater-quality data for the Fox Hills, Hell Creek, 

Rolla, and Shell Valley aquifers, and produced an assessment 

of the data for the reservation. Reservation agencies can use 

this assessment to determine future water-quality sampling 

needs to fulfill the reservation’s monitoring requirements and 

to extend tribal data coverage.

Purpose and Scope

The purpose of this report is to present an assessment 

of groundwater data for the Fox Hills, Hell Creek, Rolla, and 

Shell Valley aquifers in northern Rolette County, North Dakota 

and especially in the vicinity of the Turtle Mountain Indian 

Reservation for 1970 through 2012. This report presents data 

from available Federal, State, and tribal sources that include 

groundwater-quality data, and annual water-level data and 

annual withdrawals from the Shell Valley aquifer.

Previous Studies

Searches through Federal, State, and tribal records for 

previous investigation studies or groundwater modeling in 

Rolette County revealed earlier studies by the USGS. In 

1975, a study was done by the USGS in cooperation with the 

U.S. Public Health Service to locate a suitable groundwater 

supply for the city of Belcourt, North Dakota (Randich, 1975). 

An investigation of groundwater resources in Rolette County 

was made cooperatively by the USGS, North Dakota State 

Water Commission (NDSWC), North Dakota Geological 

Survey, and the Water Management Districts of Bottineau and 

Rolette Counties (Randich and Kuzniar, 1984). The results of 

the three-part investigation consist of an interpretative report 

describing the geology of the study area, a compilation of the 
2 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

Belcourt

Lake

Long

Lake

Upsilon

Lake

Willow

Lake

Island

Lake

Long

Lake

Carpenter

Lake

Mylo

Rolla

Rolette

St. John

Dunseith

Belcourt

ROLETTE COUNTY

W

*See fig. 1B for well information olf Cre ek

Ox Creek

Willow

Creek

Big

Coulee

TURTLE MOUNTAIN

INDIAN RESERVATION

96

93

94

95

87

88

89

91

92

90

84

83

86

82

81

85

1

4

3

2

14

13

12

11

5

6

7

8

9

10

A

EXPLANATION

Rolla aquifer

Shell Valley aquifer

Aquifers—Other

USGS well 

North Dakota State Water

Commission well 

Production well

Cities

Hell Creek and Fox Hills

aquifers

85

5

Base from U.S. Geological Survey digital data, 1983 

Universal Transverse Mercator projection, Zone 14 N 

0 2 4 8 MILES

0 4 8 KILOMETERS 2

99°40’ 100° 49°

48°40’

NORTH DAKOTA

ROLETTE

COUNTY

Figure 1. Location of the Turtle Mountain Indian Reservation and groundwater measuring wells in A, major aquifers 

and B, Shell Valley aquifer, Rolette County, North Dakota.
Introduction 3

B

Rolette

80

79

78

76 77 75 74 73

72

71

70

69

67 68

66

65 64

63

62 61

59 60

58 57

5556 54

53

52 51

50 49

48

47

46

45

44

43

42

41

40 39

38

37

35 36

34

33

32

31 30

29

28

27

26

25 24 23 22

21 20

19

18

16

15

162

129 125 126

127

128

156 133

134

135 137 143

144

145

148 146 147 149

157 150

152

153

158

155 159

99

112

97

115

98

117

103

102

119

122 116

103

120 121

123 105

104

106 107

109 108

110

124

111

132

131

138 160

136

118

101

114

113

160

17

161

Wolf

Creek

Ox

Creek

TURTLE MOUNTAIN

INDIAN RESERVATION

Rolette

Thorn

Shell Valley

130

139

141142

151

EXPLANATION

Shell Valley aquifer

Aquifer—Other

USGS well 

North Dakota State Water

Commission well 

Production well

Cities

101

24

Base from U.S. Geological Survey digital data, 1983 

Universal Transverse Mercator projection, Zone 14 N 

0 1 2 MILES

0 1 2 KILOMETERS

48°45’

48°40’

100° 99°50’

Figure 1. Location of the Turtle Mountain Indian Reservation and groundwater measuring wells in A, major aquifers 

and B, Shell Valley aquifer, Rolette County, North Dakota.—Continued
4 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

geologic and hydrologic data (Kuznair and Randich, 1982), 

and an interpretative report describing groundwater resources 

(Randich and Kuzniar, 1984).

In 1995, a study was done by the USGS in cooperation 

with the Turtle Mountain Band of Chippewa Indians that 

examined groundwater and surface-water sources to determine 

the quality of the water in the Shell Valley aquifer (Strobel, 

1997). Samples were collected and analyzed for major ions, 

selected trace metals, agricultural chemicals, and selected 

hydrocarbons. Agricultural chemicals were not detected in 

water samples from the aquifer; however, the study indicated 

the presence of hydrocarbons in the Shell Valley aquifer and 

in the surface water near the aquifer. In 1997, an additional 

study was done by the USGS to determine the occurrence, 

distribution, and concentration of hydrocarbons in and near the 

Shell Valley aquifer (Berkas, 1999). Using the enzyme-linked 

immunoassay method, analyses of the 1997 water samples 

indicated the presence of polynuclear aromatic hydrocarbons 

(PAH), polychlorinated biphenyls (PCB), and pentachlorophenol (PCP) in the study area. Because hydrocarbons were 

detected, selected samples were analyzed using the gas chromatography (GC) method to detect individual compounds and 

determine the concentrations of those compounds. Concentrations for all compounds detected using the GC method were 

less than the minimum reporting levels for each constituent 

(Berkas, 1999).

Data Sources

The two main sources of water-quality data for groundwater were the databases of the USGS National Water Information System (NWIS) database and the NDSWC database 

(table 1). The USGS collected data occasionally from 1978 

through 1998, but no data were collected again until 2012. 

The NDSWC collected water-quality data for groundwater about once every 5 years from 1974 through 2008, and 

measured monthly water levels. The purpose of the NDSWC 

general sampling is to provide historical water-quality data 

for water appropriations, and the water levels are for withdrawal permits. Water-quality data used for this assessment 

are available from the USGS NWIS database (U.S. Geological 

Survey, 2012) and the NDSWC database (North Dakota State 

Water Commission, 2012). Water-quality data for groundwater 

samples collected in the study area from 1970 through 2012 

and available from NDSWC and USGS NWIS databases are 

listed in supplements 1 and 2, respectively. Data included 

major ions, trace elements, nutrients, field properties and 

physical properties.

Some water-quality data were collected by the North 

Dakota Department of Health (NDDH) and the Turtle Mountain Tribe. The NDDH sampled selected groundwater wells in 

the Shell Valley aquifer from 1992 through 2011. The purpose 

Table 1. Sources of groundwater-quality data avaliable, 1970 through 2012.

[MI, major ions; TM, trace metals; Other, field and laboratory measurements; P, pesticides; H, hydrocarbons]

Aquifer Number

of wells

Number 

of samples 

collected

Periods of

record Types of data

North Dakota State Water Commission database

Shell Valley 66 180 1974, 1977–81, 1983, 1985, 1986, 1988, 1995, 1997, 1998, 

2002–04, 2007 

MI, TM, nitrate, other, water levels

Rolla 10 10 1978, 1979 and 1980 MI, TM, nitrate, other, water levels

Fox Hills 2 2 1978 and 1997 MI, TM, nitrate, other, water levels

Hell Creek 2 2 1978 and 1997 MI, TM, nitrate, other, water levels

U.S. Geological Survey database

Shell Valley 68 101 1988, 1995, 1997, 1998, 2012 MI, TM, nitrate, other, P1, H1

Rolla 13 14 1978, 1979 and 1980 MI, TM, nitrate, other

Fox Hills 3 3 1978 and 1997 MI, TM, nitrate, other

Hell Creek 5 5 1978 and 1997 MI, TM, nitrate, other

North Dakota Department of Health (proprietary data)

Shell Valley 20 80 1992–20112 MI, TM, nitrate, other

1

Pesticides and hydrocarbon data are published in Strobel (1995) and Berkas (1999).

2

About 20 groundwater wells were sampled 4 times or about every 5 years from 1992 through 2011.
Physical Setting of the Study Area 5

of the NDDH ambient sampling is to monitor water-quality 

data primarily for effects of agriculture practices. About 

20 private groundwater wells were sampled 4 times or about 

every 5 years during the 20-year period for major ions, selected 

trace elements, nitrate, pesticides, field properties, and physical properties. The NDDH produces internal reports using the 

data and those data are considered proprietary and not available for publication. The Turtle Mountain Tribe Public Utilities Commission collects treated water samples on a monthly 

basis from their water distribution system that blends water 

from three groundwater production wells, known as the Shell 

Valley, Rolette, and Thorn wells (fig. 1A). These water samples 

are analyzed for contaminants including microbial, inorganic 

and organic chemical contaminants, as required by the U.S. 

Environmental Protection Agency (USEPA). Because the water 

samples collected by the Turtle Mountain Tribe Public Utilities 

Commission were not collected directly from Shell Valley aquifer sampling wells, results from those water-quality analyses 

were not included in this assessment of groundwater quality.

Physical Setting of the Study Area

The Turtle Mountain Indian Reservation covers about 

72 square miles in north-central North Dakota). The topography of the reservation is predominately rolling hills, and the 

land surface is covered mostly with forests and small lakes 

in the northern part of the reservation. The southern part of 

the reservation is low rolling hills with land areas cleared for 

agriculture (North Dakota Studies, 2012).

Aquifers

The major aquifers located under or near to the Turtle 

Mountain Indian Reservation are the Fox Hills and Hell Creek 

aquifers, which are composed of bedrock materials; and 

the Rolla and Shell Valley aquifers, which are composed of 

glacial-drift materials (Randich and Kuzniar, 1984). The Fox 

Hills sandstones of the Fox Hills and Hell Creek aquifers are 

about 35 to 100 feet below land surface, and the water-bearing 

beds of the aquifers vary from about 2 to 83 feet thick (Randich and Kuzniar, 1984). The Rolla and Shell Valley aquifers 

are about 0 to 35 feet below land surface, and the waterbearing beds of the aquifers vary from about 2 to 86 feet thick 

(Randich and Kuzniar, 1984). Other small, undifferentiated 

aquifers exist under Rolette County, but these aquifers are not 

discussed in this report.

Water from the Rolla and Shell Valley aquifers is the 

major supply for the city of Rolla, North Dakota, and for the 

Turtle Mountain Indian Reservation, respectively (Randich 

and Kuzniar, 1984). Water from the Shell Valley aquifer also 

is used for the irrigation of crops in the southern portion of 

the reservation and elsewhere in Rolette County. Observations 

during visits to the reservation indicate that several lakes are 

situated in the vicinity of the aquifers. Occasionally, these 

lakes may act as recharge locations for the Rolla and Shell 

Valley aquifers. Wolf Creek, which flows near agricultural 

lands in the southern part of the reservation, has been identified as a potential source of recharge to the Shell Valley aquifer during periods of runoff (Randich and Kuzniar, 1984).

Land Use

Land use on the Turtle Mountain Indian Reservation is 

mostly recreational, with some agricultural interests especially in the southern part of the reservation (North Dakota 

Studies, 2012). Agricultural lands on the reservation are used 

for crop production or for pasture. Crop statistics for Rolette 

County, North Dakota, were accessed from the U.S. Department of Agriculture National Agriculture Statistics Service 

(U.S. Department of Agriculture, 2012). A 15-year history 

of crops grown in Rolette County shows a predominance 

of wheat production, with increased production of canola 

since 1999 (table 2). Although data on the use of agricultural 

chemicals (fertilizers, herbicides, and pesticides) for production of these crops were not available, the types and quantities 

of chemicals used on particular crops could be inferred from 

published materials about crop-production practices (North 

Dakota State University, 2012).

Table 2. Annual acreages of major crops planted 

in Rolette County, North Dakota, 1997 through 2011.

[Data obtained from http://quickstats.nass.usda.gov/; --, no 

data]

Year

Hard red 

spring and 

winter wheat

Canola

Barley 

and 

oats

Other1

1997 130,000 -- 82,500 14,100

1998 99,800 -- 69,000 22,200

1999 35,500 14,000 37,500 15,300

2000 97,800 52,500 49,400 26,300

2001 85,500 47,500 44,000 28,100

2002 89,500 50,600 56,000 39,500

2003 88,900 49,500 52,500 36,900

2004 81,000 34,500 38,000 16,100

2005 89,500 47,500 29,500 33,300

2006 106,900 42,500 22,500 19,500

2007 106,700 46,800 41,700 17,100

2008 110,800 46,600 50,000 40,100

2009 112,400 46,400 32,400 32,630

2010 105,600 63,700 25,000 39,240

2011 84,600 37,400 12,600 25,640

1

Consists of corn, flax, soybeans, and sunflowers.
6 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

Assessment of Groundwater Levels

Groundwater levels were obtained from NDSWC that 

provided monthly water levels in the Shell Valley aquifer from 

1981 through 2011. The levels from NDSWC groundwater 

wells were measured by the USGS and referenced to NDSWC 

measurement point elevations. Levels from groundwater wells 

located nearest to the Shell Valley, Thorn and Rolette production wells were selected, and levels from the last month of 

each year were used to estimate the annual water levels from 

the Shell Valley aquifer.

Water levels in the Shell Valley aquifer often fluctuate 

by several feet annually in response to natural processes and 

to municipal and irrigation pumping, although water-level 

recovery was noted during periods with no pumping activity (Randich and Kuzniar, 1984). Annual water withdrawals 

from the Shell Valley aquifer for 1981 through 2011 show a 

relatively steady increase from 1981 through 2006 (fig. 2). 

Aquifer water levels tended to decrease during the period of 

increased withdrawals, but from 1999 to 2011, water levels 

mostly increased or stabilized (fig. 3).

Assessment of Groundwater Quality

Groundwater-quality data were obtained from several 

groundwater sampling wells in Rolette County (tables 3 

and 4). Groundwater sampling wells discussed in this report 

were located in the Fox Hills, Hell Creek, Rolla, and Shell 

Valley aquifers only. Sample concentrations also were compared to USEPA drinking water maximum contaminate levels 

(MCL) and secondary maximum contaminate level (SMCL) 

(U.S. Environmental Protection Agency, 2012). An MCL 

refers to the highest level or concentration that is allowed 

in drinking water for protection of health and is an enforceable standard. An SMCL is a nonenforceable guideline and 

addresses either cosmetic or aesthetic effects. Water concentrations above a SMCL may result in tooth or skin discoloration 

or taste, odor, or color issues.

Fox Hills and Hell Creek Aquifers

Very few groundwater samples have been obtained from 

the Fox Hills and Hell Creek aquifers (supplements 1 and 2). 

0

200

400

600

800

1,000

1,200

1,400

1,600

1,800

2,000

1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011

Withdrawals, in acre-feet

Year

Figure 2. Annual water withdrawals from the Shell Valley aquifer, 1981 through 2011.
Assessment of Groundwater Quality 7

1,710

1,715

1,720

1,725

1,730

1,735

1/1/19811/1/19831/1/19851/1/19871/1/19891/1/19911/1/19931/1/19951/1/19971/1/19991/1/20011/1/20031/1/20051/1/20071/1/20091/1/2011

Shell Valley production well

Water-level elevation above mean sea level, in feet Water-level elevation above mean sea level, in feet 1,575

1,580

1,585

1,590

1,595

1,600

1,605

1,610

1/1/19811/1/19831/1/19851/1/19871/1/19891/1/19911/1/19931/1/19951/1/19971/1/19991/1/20011/1/20031/1/20051/1/20071/1/20091/1/2011

Thorn production well

1,604

1,606

1,608

1,610

1,612

1,614

1,616

1,618

1/1/19811/1/19831/1/19851/1/19871/1/19891/1/19911/1/19931/1/19951/1/19971/1/19991/1/20011/1/20031/1/20051/1/20071/1/20091/1/2011

Rolette production well

Water-level elevation above mean sea level, in feet

Year

Year

Year

Figure 3. Annual water levels near Rolette, Thorn, and Shell Valley 

production wells, 1981 through 2011.

No samples have been obtained since 1997 (Berkas, 1999). 

Data from 1997 indicate somewhat greater concentrations of 

calcium, magnesium, and sulfate than the data from 1978. In 

addition, no information about pesticides and hydrocarbons 

exist in the datasets. The scarcity of data from the Fox Hills 

and Hell Creek aquifers limits any reasonable assessments that 

can be made about the aquifers, however all concentrations of 

manganese, sulfate, and dissolved solids exceeded the USEPA 

SMCL.

Rolla Aquifer

Although more groundwater samples have been obtained 

from the Rolla aquifer than from the Fox Hills and Hell Creek 

aquifers, data for the Rolla aquifer exist only for the period 

1978 through 1980 (supplements 1 and 2). The concentrations 

of iron, manganese, sulfate and dissolved solids in most of the 

samples obtained exceeded the USEPA SMCL (U.S. Environmental Protection Agency, 2012). Also, no samples were 

analyzed for pesticides and hydrocarbons. The limited period 

of time during which water-quality samples were collected 

from the Rolla aquifer precludes attempts to discuss possible 

patterns in water-quality constituents.

Shell Valley Aquifer

Numerous water-quality samples were obtained from 

the Shell Valley aquifer (supplements 1 and 2; fig. 4). The 

NDSWC groundwater well 160-072-02CBC (well 28 on 

fig. 1B) had consistently large values for specific conductivity, 

magnesium, potassium, sodium, bicarbonate, sulfate, chloride, 

and dissolved solids for the five samples collected from 1981 

through 2007 (supplement 1). Groundwater well 160-072-

02CBC (well 28 on fig. 1B) is located between two wetlands 

and the groundwater at that well may be affected influenced 

by surface-water interaction. About one-half of the NDSWC 

water-quality samples from the Shell Valley aquifer had concentrations of iron, manganese, sulfate, and dissolved solids 

that exceeded the USEPA SMCL (U.S. Environmental Protection Agency, 2012; fig. 4). Except for the few water-quality 

samples obtained during the special studies in 1995 and 1997 

(Strobel, 1997; Berkas, 1999), no samples were analyzed for 

pesticides and hydrocarbons. The USGS water-quality samples 

from the Shell Valley aquifer also had concentrations of iron, 

manganese, sulfate, and dissolved solids that exceeded the 

USEPA secondary maximum contaminant levels (U.S. Environmental Protection Agency, 2012; fig. 5) Overall, the data 

from the Shell Valley aquifer did not indicate any obvious 

patterns in water-quality constituent concentrations.

Two water-quality samples, one obtained in 1995 from 

USGS groundwater well 160-071-24DDD (well 107 on 

fig. 1B) and another sample obtained in 2012 from USGS 

groundwater well 161-072-35CDC (well 160 on fig. 1B), indicated arsenic concentrations greater than 30 micrograms per 

liter (supplement 2). These two samples were the only ones 
8 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

Table 3. Locations of North Dakota State Water Commision groundwater sampling wells 

in the Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers, Rolette County, North Dakota.

Well

number

(fig. 1)

Aquifer Site name Latitude, 

decimal degrees

Lonitude, 

decimal degrees

1 Fox Hills 163-073-11CCC1 48.951118 -100.094355

2 Fox Hills 163-073-11CCC1 48.951118 -100.094355

3 Hell Creek 163-073-11CCC2 48.951118 -100.094355

4 Hell Creek 163-073-11CCC2 48.951118 -100.094355

5 Rolla 162-069-11BBB 48.876723 -99.568226

6 Rolla 162-069-17ADB 48.858761 -99.617635

7 Rolla 162-069-17DCA 48.851522 -99.620382

8 Rolla 162-069-20ABA 48.847892 -99.620348

9 Rolla 162-069-20DDD1 48.835132 -99.614808

10 Rolla 162-069-20DDD2 48.835132 -99.614808

11 Rolla 163-069-02BBB 48.977950 -99.568324

12 Rolla 163-069-15AAA 48.948938 -99.571001

13 Rolla 163-069-26DDD 48.907270 -99.548839

14 Rolla 164-069-28DDD 48.993768 -99.593090

15 Shell Valley 160-071-05BAA 48.717664 -99.853987

16 Shell Valley 160-071-07AAA 48.703430 -99.864797

17 Shell Valley 160-071-07BBC 48.701605 -99.882961

18 Shell Valley 160-071-07BCC 48.697980 -99.882954

19 Shell Valley 160-071-16BBB 48.688967 -99.840183

20 Shell Valley 160-071-19DDD 48.661846 -99.864887

21 Shell Valley 160-071-21CCB 48.663597 -99.840240

22 Shell Valley 160-071-22DDD 48.661676 -99.799083

23 Shell Valley 160-071-24DDD 48.661703 -99.755465

24 Shell Valley 160-071-26AAA 48.659863 -99.777329

25 Shell Valley 160-071-28AAA 48.659982 -99.821059

26 Shell Valley 160-071-29ADD 48.654571 -99.843055

27 Shell Valley 160-072-02AAA 48.717648 -99.907480

28 Shell Valley 160-072-02CBC 48.708838 -99.926626

29 Shell Valley 160-072-03BBB1 48.717749 -99.948501

30 Shell Valley 160-072-03BBC 48.715966 -99.948499

31 Shell Valley 160-072-05ADD 48.712431 -99.973020

32 Shell Valley 160-072-12AAB 48.703485 -99.888344

33 Shell Valley 160-072-12DAD 48.694424 -99.885612

34 Shell Valley 160-072-12DDD 48.690816 -99.885609

35 Shell Valley 160-072-13CCC 48.676413 -99.904896

36 Shell Valley 160-072-13DDD 48.676310 -99.885842

37 Shell Valley 160-072-24CCB 48.663706 -99.904967

38 Shell Valley 161-071-03BCC2 48.799213 -99.852847

39 Shell Valley 161-071-03CDD4 48.792029 -99.844619
Assessment of Groundwater Quality 9

Table 3. Locations of North Dakota State Water Commision groundwater sampling 

wells in the Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers, Rolette County, North 

Dakota.—Continued

Well

number

(fig. 1)

Aquifer Site name Latitude, 

decimal degrees

Lonitude, 

decimal degrees

40 Shell Valley 161-071-04CCC 48.791937 -99.874838

41 Shell Valley 161-071-07DDD 48.777416 -99.899589

42 Shell Valley 161-071-08BCB 48.786528 -99.896868

43 Shell Valley 161-071-08CBB 48.782862 -99.896865

44 Shell Valley 161-071-08CCB 48.779202 -99.896862

45 Shell Valley 161-071-08DCD 48.777351 -99.883093

46 Shell Valley 161-071-09AAD1 48.788330 -99.855632

47 Shell Valley 161-071-09AAD2 48.788330 -99.855632

48 Shell Valley 161-071-09ADD 48.784690 -99.855640

49 Shell Valley 161-071-09CCC 48.777368 -99.874852

50 Shell Valley 161-071-09D 48.780167 -99.859779

51 Shell Valley 161-071-10BAA 48.790221 -99.844613

52 Shell Valley 161-071-10BBA 48.790191 -99.850115

53 Shell Valley 161-071-10BBB 48.790181 -99.852873

54 Shell Valley 161-071-15BBA 48.775669 -99.850235

55 Shell Valley 161-071-16AAB 48.775653 -99.858430

56 Shell Valley 161-071-16AAB1 48.775653 -99.858430

57 Shell Valley 161-071-16AAD 48.773836 -99.855696

58 Shell Valley 161-071-16BCC 48.770180 -99.874856

59 Shell Valley 161-071-16CCD 48.762966 -99.872133

60 Shell Valley 161-071-16CDD 48.762947 -99.866651

61 Shell Valley 161-071-21CCC1 48.748431 -99.875014

62 Shell Valley 161-071-21CCC2 48.748431 -99.875014

63 Shell Valley 161-071-22BBB 48.761069 -99.853132

64 Shell Valley 161-071-28BAB 48.746593 -99.869460

65 Shell Valley 161-071-29AAB 48.746646 -99.880433

66 Shell Valley 161-071-29DAD 48.737601 -99.877642

67 Shell Valley 161-071-32DCC 48.719428 -99.885780

68 Shell Valley 161-071-33CDD 48.719513 -99.866613

69 Shell Valley 161-071-34DDD 48.719440 -99.833751

70 Shell Valley 161-072-01DDD 48.792107 -99.921345

71 Shell Valley 161-072-02BBB 48.804759 -99.962423

72 Shell Valley 161-072-34ADB 48.728556 -99.967965

73 Shell Valley 161-072-35CCC 48.719466 -99.962539

74 Shell Valley 161-072-35CCD 48.719478 -99.959798

75 Shell Valley 161-072-35CDC 48.719501 -99.957053

76 Shell Valley 161-072-35CDD 48.719513 -99.954304

77 Shell Valley 161-072-35DCC 48.719542 -99.951550

78 Shell Valley 162-071-36CBC2 48.809937 -99.808876

79 Shell Valley 161-071-16DCD1 48.762805 -99.861609

80 Shell Valley 161-071-16DCD1 48.762805 -99.861609
10 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

Table 4. Locations of U.S. Geological Survey (USGS) groundwater sampling wells in the Fox Hills, Hell 

Creek, Rolla, and Shell Valley aquifers, Rolette County, North Dakota.

Well

number

(fig. 1)

Aquifer

USGS well 

identification 

number

Site name Latitude, 

decimal degrees

Longitude, 

decimal degrees

81 Fox Hills 485659099570501 163-072-14ABB 48.949726 -99.951796

82 Fox Hills 485707100053701 163-073-11CCC1 48.951949 -100.094018

83 Hell Creek 485027099450401 162-070-20DBA 48.840838 -99.751536

84 Hell Creek 485330100100301 162-073-06ABA 48.891670 -100.167910

85 Hell Creek 484955100030801 162-073-25AAD 48.831946 -100.052634

86 Hell Creek 485707100053702 163-073-11CCC2 48.951949 -100.094018

87 Rolla 485237099340601 162-069-11BBB 48.876951 -99.568754

88 Rolla 485131099370301 162-069-17ADB1 48.858617 -99.617922

89 Rolla 485105099371301 162-069-17DCA 48.851395 -99.620700

90 Rolla 485052099371302 162-069-20ABA2 48.847783 -99.620700

91 Rolla 485007099365301 162-069-20DDD1 48.835283 -99.615145

92 Rolla 485007099365302 162-069-20DDD2 48.835283 -99.615145

93 Rolla 485844099340501 163-069-02BBB 48.978897 -99.568472

94 Rolla 485659099341501 163-069-15AAA 48.949730 -99.571251

95 Rolla 485429099324701 163-069-25CCC 48.908063 -99.546808

96 Rolla 485944099353501 164-069-28DDD 48.995564 -99.593472

97 Shell Valley 484304099511301 160-071-05BAA 48.717778 -99.854034

98 Shell Valley 484217099502901 160-071-05DDD 48.704723 -99.841812

99 Shell Valley 484307099514801 160-071-06AAA 48.718612 -99.863756

100 Shell Valley 484212099515301 160-071-07AAA 48.703334 -99.865144

101 Shell Valley 484205099530101 160-071-07BBC 48.701389 -99.884032

102 Shell Valley 484152099530101 160-071-07BCC 48.697778 -99.884032

103 Shell Valley 484119099502401 160-071-16BBB1 48.688611 -99.840423

104 Shell Valley 483942099515301 160-071-19DDD 48.661666 -99.865143

105 Shell Valley 483948099502401 160-071-21CCB 48.663333 -99.840422

106 Shell Valley 483942099475801 160-071-22DDD 48.661666 -99.799868

107 Shell Valley 483941099452101 160-071-24DDD 48.661389 -99.756259

108 Shell Valley 483935099463901 160-071-26AAA 48.659722 -99.777925

109 Shell Valley 483935099491601 160-071-28AAA1 48.659722 -99.821534

110 Shell Valley 483916099503401 160-071-29ADD 48.654444 -99.843199

111 Shell Valley 483755099514801 160-071-31DDD 48.631943 -99.863754

112 Shell Valley 484304099542901 160-072-02AAA 48.717778 -99.908476

113 Shell Valley 484304099565501 160-072-03BBB1 48.717778 -99.949029

114 Shell Valley 484258099565501 160-072-03BBC 48.716111 -99.949029

115 Shell Valley 484245099582301 160-072-05ADD 48.712500 -99.973472

116 Shell Valley 484124099554001 160-072-10DDD 48.690000 -99.928196

117 Shell Valley 484212099532101 160-072-12AAB 48.703333 -99.889587

118 Shell Valley 484139099531101 160-072-12DAD 48.694167 -99.886810

119 Shell Valley 484126099531101 160-072-12DDD 48.690555 -99.886810

120 Shell Valley 484034099541901 160-072-13CCC1 48.676111 -99.905697
Assessment of Groundwater Quality 11

Table 4. Locations of U.S. Geological Survey (USGS) groundwater sampling wells in the Fox Hills, Hell 

Creek, Rolla, and Shell Valley aquifers, Rolette County, North Dakota.—Continued

Well

number

(fig. 1)

Aquifer

USGS well 

identification 

number

Site name Latitude, 

decimal degrees

Longitude, 

decimal degrees

121 Shell Valley 484034099531101 160-072-13DDD 48.676111 -99.886809

122 Shell Valley 484124099565701 160-072-15BBB 48.689999 -99.949584

123 Shell Valley 483948099541901 160-072-24CCB 48.663333 -99.905697

124 Shell Valley 483847099530301 160-072-36AAA 48.646388 -99.884586

125 Shell Valley 484757099494201 161-071-02BCD 48.799169 -99.828756

126 Shell Valley 484757099493201 161-071-02BDC 48.799169 -99.825978

127 Shell Valley 484750099495102 161-071-02CBB2 48.797225 -99.831256

128 Shell Valley 484744099495101 161-071-02CBC1 48.795558 -99.831256

129 Shell Valley 484757099511002 161-071-03BCC2 48.799169 -99.853199

130 Shell Valley 484731099510001 161-071-03CCD 48.791947 -99.850422

131 Shell Valley 484731099505001 161-071-03CDC1 48.791947 -99.847644

132 Shell Valley 484731099504104 161-071-03CDD4 48.791947 -99.845144

133 Shell Valley 484731099522901 161-071-04CCC 48.791946 -99.875142

134 Shell Valley 484728099535301 161-071-07AAAA 48.791113 -99.898474

135 Shell Valley 484639099535701 161-071-07DDD1 48.777501 -99.899586

136 Shell Valley 484712099534701 161-071-08BCB1 48.786668 -99.896808

137 Shell Valley 484639099525801 161-071-08DCD 48.777502 -99.883198

138 Shell Valley 484639099522901 161-071-09CCC 48.777502 -99.875143

139 Shell Valley 484724099511001 161-071-10BBB 48.790002 -99.853199

140 Shell Valley 484632099510001 161-071-15BBA 48.775558 -99.850422

141 Shell Valley 484632099513001 161-071-16AAB1 48.775557 -99.858755

142 Shell Valley 484632099513002 161-071-16AAB2 48.775557 -99.858755

143 Shell Valley 484632099514001 161-071-16ABA 48.775557 -99.861533

144 Shell Valley 484613099522901 161-071-16BCC 48.770279 -99.875144

145 Shell Valley 484547099521901 161-071-16CCD 48.763057 -99.872366

146 Shell Valley 484547099515901 161-071-16CDD 48.763057 -99.866811

147 Shell Valley 484547099514001 161-071-16DCD1 48.763057 -99.861534

148 Shell Valley 484542099523401 161-071-20AAA 48.761668 -99.876533

149 Shell Valley 484540099511001 161-071-22BBB 48.761113 -99.853201

150 Shell Valley 484452099511301 161-071-22CCC2 48.747779 -99.854035

151 Shell Valley 484448099520901 161-071-28BAB 48.746668 -99.869589

152 Shell Valley 484448099524801 161-071-29AAB 48.746668 -99.880422

153 Shell Valley 484416099523901 161-071-29DAD 48.737779 -99.877922

154 Shell Valley 481311099525801 161-071-32DCC 48.219723 -99.883188

155 Shell Valley 484311099515901 161-071-33CDD 48.719723 -99.866811

156 Shell Valley 484731099551601 161-072-01DDD 48.791946 -99.921529

157 Shell Valley 484455099574401 161-072-23CCC 48.748611 -99.962640

158 Shell Valley 484343099580301 161-072-34ADB 48.728611 -99.967917

159 Shell Valley 484310099573401 161-072-35CCD 48.719444 -99.959862

160 Shell Valley 484310099572401 161-072-35CDC 48.719444 -99.957084

161 Shell Valley 484310099563501 161-072-35DDD 48.719444 -99.943474

162 Shell Valley 484838099483101 162-071-36CBC1 48.810559 -99.809034

163 Shell Valley 484838099483102 162-071-36CBC2 48.810559 -99.809034
12 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

0

200

400

600

800

1,000

Sulfate, in milligrams per liter

0

10

20

30

Iron, in milligrams per liter

0

2

4

6

8

10

Manganese, in milligrams per liter

0

500

1,000

1,500

2,000

Dissolved solids, in milligrams per liter

Five values occurred in excess of 25,000 milligrams per liter (not shown)

U.S. Environmental Protection Agency secondary maximum contaminant level (250 milligrams per liter)

U.S. Environmental Protection Agency secondary maximum contaminant level (0.3 milligrams per liter)

U.S. Environmental Protection Agency secondary maximum contaminant level (0.05 milligrams per liter)

Five values occurred in excess of 37,000 milligrams per liter (not shown)

U.S. Environmental Protection Agency secondary maximum contaminant level (500 milligrams per liter)

10/1/19706/27/19733/23/1976

12/18/1978

9/13/1981

6/9/19843/6/1987

11/30/1989

8/26/19925/23/19952/16/1998

11/12/2000

8/9/20035/5/2006

1/29/2009

10/1/19706/27/19733/23/1976

12/18/1978

9/13/1981

6/9/1984

3/6/1987

11/30/1989

8/26/19925/23/19952/16/1998

11/12/2000

8/9/2003

5/5/2006

1/29/2009

10/1/1970

6/27/19733/23/1976

12/18/1978

9/13/1981

6/9/19843/6/1987

11/30/1989

8/26/1992

5/23/1995

2/16/1998

11/12/2000

8/9/2003

5/5/2006

1/29/2009

10/1/19706/27/19733/23/1976

12/18/1978

9/13/1981

6/9/19843/6/1987

11/30/1989

8/26/19925/23/19952/16/1998

11/12/2000

8/9/2003

5/5/2006

1/29/2009

Figure 4. Groundwater concentrations from North Dakota State Water Commission wells in the Shell 

Valley aquifer for selected constituents that exceeded the U.S. Environmental Protection Agency secondary 

maximum contaminant levels.
Assessment of Groundwater Quality 13

0

200

400

600

800

1,000

1,200

Sulfate, in milligrams per liter

U.S. Environmental Protection Agency secondary maximum contaminant level (250 milligrams per liter) 

U.S. Environmental Protection Agency secondary maximum contaminant level (500 milligrams per liter) 

U.S. Environmental Protection Agency secondary maximum contaminant level (0.3 milligrams per liter), reported here as 300 micrograms per liter 

U.S. Environmental Protection Agency secondary maximum contaminant level (0.5 milligrams per liter), reported here as 50 micrograms per liter 

0

2,000

4,000

6,000

8,000

10,000

12,000

Iron, in milligrams per liter

0

200

400

600

800

1,000

1,200

Manganese, in milligrams per liter

0

500

1,000

1,500

2,000

2,500

Dissolved solids, in milligrams per liter

10/1/1970

12/9/19722/17/19754/27/1977

7/6/1979

9/13/1981

11/22/1983

1/30/1986

4/9/1988

6/18/19908/26/199211/4/19941/12/19973/23/1999

5/31/2001

8/9/2003

10/17/12005

12/26/2007

3/5/2010

5/13/2012

10/1/1970

12/9/19722/17/19754/27/1977

7/6/1979

9/13/1981

11/22/1983

1/30/1986

4/9/1988

6/18/1990

8/26/1992

11/4/1994

1/12/1997

3/23/1999

5/31/2001

8/9/2003

10/17/12005

12/26/2007

3/5/2010

5/13/2012

10/1/1970

12/9/19722/17/19754/27/1977

7/6/1979

9/13/1981

11/22/1983

1/30/1986

4/9/1988

6/18/19908/26/1992

11/4/19941/12/1997

3/23/1999

5/31/2001

8/9/2003

10/17/12005

12/26/2007

3/5/2010

5/13/2012

10/1/1970

12/9/19722/17/1975

4/27/1977

7/6/1979

9/13/1981

11/22/1983

1/30/1986

4/9/1988

6/18/19908/26/199211/4/19941/12/1997

3/23/1999

5/31/2001

8/9/2003

10/17/12005

12/26/2007

3/5/2010

5/13/2012

Figure 5. Groundwater concentrations from U.S. Geological Survey wells in the Shell Valley aquifer for selected 

constituents that exceeded the U.S. Environmental Protection Agency secondary maximum contaminant levels.
14 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

in the USGS database that had arsenic concentrations greater 

than the standard limit for drinking water (10 micrograms 

per liter). Comparisons of the USGS samples with samples 

from nearby NDSWC groundwater wells could not be made 

because samples collected by the NDSWC were not analyzed 

for arsenic (supplement 1). However, USGS groundwater well 

161-072-35CDC (well 160 on fig. 1B) also had an arsenic 

concentration of 2 micrograms per liter, suggesting that the 

arsenic concentration is not always high and other factors may 

be affecting he concentration of arsenic in this well.

Implications

Water-quality data for the Fox Hills, Hell Creek, Rolla, 

and Shell Valley aquifers are collected by various agencies for 

different studies and objectives. Data are collected for specific 

studies and on-going sampling programs. Water samples are 

collected from public groundwater observation wells and from 

private groundwater wells for selected constituents to meet 

agency objectives.

The Turtle Mountain Tribe may consider coordinating 

with Federal and State agencies that have sampling efforts and 

data to perform future assessments of groundwater quality. 

The results of the coordination may provide an efficient sampling program, and the design of a long-term and consistent 

strategy for groundwater sampling that may be advantageous 

for monitoring aquifer water quality. The types of water-quality data (major ions, metals, pesticides, hydrocarbons, and so 

on) collected in the future may be revised to provide missing 

information needed for current or future activities in or near 

the Shell Valley aquifer. These data also may be beneficial to 

other tribal, Federal, and State interests. The usefulness of the 

data may be enhanced while maintaining or perhaps reducing sampling costs. A modified or coordinated sampling plan 

could provide data from which patterns may be identified in 

relation to changes in climate and use or both.

Summary

The Turtle Mountain Indian Reservation relies on 

groundwater supplies to meet the demands of community and 

economic needs. The U.S. Geological Survey, in cooperation 

with the Turtle Mountain Band of Chippewa Indians, examined historical groundwater-level and groundwater-quality 

data for the Fox Hills, Hell Creek, Rolla, and Shell Valley 

aquifers, and produced an assessment of the data for the reservation. Water from the Rolla and Shell Valley aquifers is the 

major supply for the city of Rolla, North Dakota, and for the 

Turtle Mountain Indian Reservation, respectively.

Water levels in the Shell Valley aquifer often fluctuate 

by several feet annually in response to natural processes and 

to municipal and irrigation pumping, although water-level 

recovery was noted during periods with no pumping activity. 

Aquifer water levels tended to decrease during the period of 

increased withdrawals, but from 1999 to 2011, water levels 

mostly increased or stabilized.

The two main sources of water-quality data for groundwater were the databases of the U.S. Geological Survey and 

the North Dakota State Water Commission. Data included 

major ions, trac e elements, nutrients, field properties, and 

physical properties. The North Dakota State Water Commission collected water-quality data for groundwater about once 

every 5 years from 1974 through 2008. The North Dakota 

Department of Health sampled selected groundwater wells 

in the Shell Valley aquifer from 1992 through 2011 for major 

ions, selected trace elements, nitrate, field properties, and 

physical properties; however, those data are considered proprietary and not available for publication. The Turtle Mountain Tribe Public Utilities Commission collects treated water 

samples on a monthly basis from their water distribution system, but because the water samples were not collected directly 

from Shell Valley aquifer sampling wells, those data were not 

included in the assessment of groundwater quality.

The Fox Hills and Hell Creek aquifers had very few 

groundwater samples obtained. The lack of data limits any 

reasonable assessments that can be made about these aquifers. 

The concentrations for sulfate, manganese, and dissolved 

solids all exceeded the U.S. Environmental Protection Agency 

secondary maximum contaminate level. Data for the Rolla 

aquifer only exist for the period 1978 through 1980. The 

concentrations of manganese, sulfate, and dissolved solids 

exceeded the U.S. Environmental Protection Agency secondary maximum contaminate level. No samples were analyzed 

for pesticides and hydrocarbons.

Numerous water-quality samples have been obtained 

from the Shell Valley aquifer. The North Dakota State Water 

Commission groundwater well 160-072-02CBC (well 28 on 

fig. 1B) had consistently large values for specific conductivity, 

magnesium, potassium, sodium, bicarbonate, sulfate chloride, 

and dissolved solids for the five samples collected from 1981 

through 2007. About one-half of the water-quality samples 

from the Shell Valley aquifer had concentrations of iron, 

manganese, sulfate, and dissolved solids that exceeded the 

U.S. Environmental Protection Agency secondary maximum 

contaminate level. Overall, the data from the Shell Valley 

aquifer did not indicate obvious patterns in concentrations.

References Cited

Berkas, W.R., 1999, Occurrence, distribution, and concentration of hydrocarbons in and near the Shell Valley Aquifer, 

North Dakota: U.S. Geological Survey Open-File Report 

99–194, 20 p.
References Cited 15

Kuzniar, R.L., and Randich, P.G., 1982, Ground-water data 

for Bottineau and Rolette Counties, North Dakota: North 

Dakota Geological Survey Bulletin 78, part II, and North 

Dakota State Water Commission County Ground-Water 

Studies 35, part II, 742 p.

North Dakota State University, 2012, Educational materials, 

crop production: accessed November 5, 2012, at http://www.

ag.ndsu.edu/pubs/crop_production.htm.

North Dakota Studies, 2012, The history and the culture of 

the Turtle Mountain band of Chippewa—Demographics: 

accessed August 30, 2012, at http://www.ndstudies.org/

resources/IndianStudies/turtlemountain/demographics_

land.html.

North Dakota State Water Commission, 2012, Water in North 

Dakota: accessed December 10, 2012, at (http://www.swc.

state.nd.us/4dlink2/4dcgi/wellsearchform/Map%20and%20

Data%20Resources.

Randich, P.G., 1975, Ground-water availability in the Belcourt 

area, Rolette County, North Dakota : Geological Survey 

Open-File Report 75–104, 36 p.

Randich, P.G., and Kuzniar, R.L., 1984, Ground-water 

resources of Bottineau and Rolette Counties, North Dakota: 

North Dakota Geological Survey Bulletin 78, part III, and 

North Dakota State Water Commission County GroundWater Studies 35, part III, 41 p.

Strobel, M.L., 1997, Hydrogeology and water quality of 

the Shell Valley aquifer, Rolette County, North Dakota: 

U.S. Geological Survey Water-Resources Investigations 

Report 97–4291, 25 p.

U.S. Geological Survey, 2012, National Water Information 

System (NWISWeb): U.S. Geological Survey database, 

accessed December 10, 2012, at http://waterdata.usgs.gov/

nd/nwis/.

U.S. Department of Agriculture, 2012, National agriculture 

statistics service quick stats: accessed July 18, 2012, at 

http://quickstats.nass.usda.gov/.

U.S. Environmental Protection Agency, 2012, 2012 Edition 

of the Drinking Water Standards and Health Advisories: 

accessed October 15, 2012, at http://water.epa.gov/action/

advisories/drinking/upload/dwstandards2012.pdf.
16 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012
Supplements 17

Supplements

Supplement 1. Water-quality data available in the North Dakota State Water Commission database 

for the Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers, 1970 through 2012. The Excel file may be 

downloaded from http://pubs.usgs.gov/ds/732.downloads/supplement_1.xlsx.

Supplement 2. Water-quality data available in the U.S. Geological Survey database for the Fox Hills, 

Hell Creek, Rolla, and Shell Valley aquifers, 1970 through 2012. The Excel file may be downloaded 

from http://pubs.usgs.gov/ds/732.downloads/supplement_2.xlsx.
18 Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012

Publishing support provided by: 

Rolla Publishing Service Center 

For more information concerning this publication, contact:

Director, USGS North Dakota Water Science Center

821 East Interstate Avenue

Bismarck, North Dakota 58503

(701) 250–7400

Or visit the North Dakota Water Science Center Web site at: 

http://nd.water.usgs.gov/

Lundgren and Vining—Assessment of Groundwater Quality Data for the Turtle Mountain Indian Reservation, Rolette County, North Dakota, 1970–2012—DS 732