a .1...
1. =55...
.. 2

v2.3 2'
. :3 .1 .135:
1.. ’5

.2};
4.55

y»;2.3.§.;¢.$h:.l
.5 . 5?qu .23;
, 21.....12 2:2:
2:. ‘ $3,

:J:II:; :3:
al v (Kiri: ‘

93+ 4......

iii: 3
I...‘

‘ 5‘“

rain

 

TYLIBRARIES

ll“

 

 

l

 

 

 

 

 

 

 

 

 

WWWWWNWWW

31293010

This is to certify that the

dissertation entitled
Identification of an Isotopic and Hydrochemical

Anomaly in the Discharge Area of the Fox Hills
Aquifer, South—Central North Dakota:
Evidence for Pleistocene Subglacial Recharge?

presented by

Catherine Anne Carlson

has been accepted towards fulfillment
of the requirements for

Ph-D- mgmehiGeological Sciences

 

MSUL: an Affirmative Anion/Equal Opportunity Institulion 0-12771

 

 

 
    
   

  

LIERARY
Michigan State
University

PLACE IN RETURN BOX to remove this checkout from your record.
TO AVOID FINES rotum on or before date duo.

DATE DUE DATE DUE DATE DUE

 

MSU Is An Affirmative Action/Equal Opportunity Institution
cfldmmuno-DJ

 

 

 

 

IDENTIFICATION OF AN ISOTOPIC AND HYDROCHEMICAL ANOMALY IN
THE DISCHARGE AREA OF THE FOX HILLS AQUIFER,
SOUTH—CENTRAL NORTH DAKOTA:

EVIDENCE FOR PLEISTOCENE SUBGLACIAL RECHARGE?

By

Catherine Anne Carlson

A DISSERTATION

Submitted to
Michigan State University
in partial fullfiliment of the requirements
for the degree of

DOCTOR OF PHILOSOPHY

Department of Geological Sciences

1994

 

 

ABSTRACT
IDENTIFICATION OF AN ISOTOPIC AND HYDROCHEMICAL ANOMALY IN
THE DISCHARGE AREA OF THE FOX HILLS AQUIFER,
SOUTH—CENTRAL NORTH DAKOTA:
EVIDENCE FOR PLEISTOCENE SUBGLACIAL RECHARGE?
By

Catherine Anne Carlson

Various researchers have suggested that groundwater flow patterns of
certain aquifers may have been altered during the Pleistocene because glacial
ice blocked the aquifers’ regional discharge areas and subglacial water was
available for recharge. In particular, it has been suggested that the Northern
Great Plains Aquifer System (NGPAS) may have experienced changes in its flow
system, including temporary recharge of meltwater in the discharge area, when
Pleistocene glaciers overrode the regional discharge area. The Fox Hills aquifer
is the stratigraphically highest regional aquifer in the NGPAS and, therefore, is
the aquifer most likely to be influenced by glaciation. Hydrogeologic,
hydrogeochemical, isotopic, and modeling approaches were combined to
investigate the effect of glaciation on the Fox Hills aquifer.

Sodium—bicarbonate-sulfate type water in the discharge area of the Fox
Hills aquifer of south—central North Dakota is a water chemistry anomaly, since
upgradient water is of the sodium—bicarbonate-chloride type. The chloride
distribution in the aquifer suggests that a freshwater source contributed about

90% of the present water in the discharge area. It is unlikely that local recharge

 

 

under present climatic conditions could explain this increase in water volume.
Water chemistry data indicate that leakage from the underlying high-chloride
Dakota aquifer is not the source of the freshwater recharge. Stable isotope data
suggest that water in the discharge area was precipitated in a cooler (than
modern) climate, such as was prevalent during the Pleistocene. D—excess
values suggest that at least two paleowaters are present in the discharge area-
a low-chloride, high d-excess water and a high-chloride, low d-excess water.
The low-chloride, high d-excess water is coincident with the water chemistry
anomaly. Two ice sheet margins, each representing a number of pulses, have
been documented in the study area. It is speculated that the discharge area was
temporarily recharged with local precipitation during the Pleistocene due to the
hydraulic gradient imposed by an overriding ice sheet. Stable isotope data
suggest that proglacial lakes were not significant sources of water to the

discharge area.

 

Copyright by
CATHERINE ANNE CARLSON
1994

 

In Memory of Emma K. Lange

 

ACKNOWLEDGMENTS

This dissertation would not have been possible without the support and
guidance of Grahame J. Larson--committee chair, advisor, mentor, and friend. I
deeply appreciate his advice, encouragement, professional assistanCe, and his
generosity with his time and knowledge. I gratefully acknowledge my committee
members who each made unique and necessary contributions to this work:
Grahame J. Larson, Roger B. Wallace, Nancy 0. Jannik (Winona State
University), Nathaniel E. Ostrom, James A. Clark (Calvin College), and Duncan
Sibley (defense substitute).

Financial support for this research was generously provided by NASA
Space Grant Fellowship, North Dakota Space Grant College, University of North
Dakota; Lucille Drake Pringle Endowed Fellowship, Department of Geological
Sciences, Michigan State University; Association of Ground Water Scientists
and Engineers Graduate Student Research Fellowship; Grant-in—Aid of
Research, Sigma Xi, The Scientific Research Society; and College of Natural
Science Graduate Continuing Fellowship, Michigan State University.

l extend heartfelt thanks to Claire Carlson and Diane Smith, whose love

sustained me during this adventure.

\‘i

 

TABLE OF CONTENTS

LIST OF TABLES ................................................................................................. xi
LIST OF FIGURES ............................................................................................. xii
INTRODUCTION .................................................................................................. 1
Statement of the Problem ............................ . .............................................. 1

The Test Aquifer ......................................................................................... 2
Investigative Techniques ............................................................................ 3
Geology ............................................................................................ 3
Hydrogeology ................................................................................... 3
Hydrogeochemistry ........... . ............................................................... 5

Stable Isotopes ................................................................................. 5
Paleohydrologic Responses ............................................................. 5

Potential Significance ................................................................................. 6
CHAPTER 1: GEOLOGY ...................................................................................... 7
Literature Review ........................................................................................ 7

The Williston Basin: Formation and Structure .................................. 7

Subsurface Stratigraphy ................................................................... 9
Hydrostratigraphic Units ................................................................. 12

Glacial History ................................................................................ 14

vii

 

 

Data Analysis and Interpretation .............................................................. 20
Fox Hills Formation Subcrop Map .................................................. 20

Fox Hills Formation Sandstone. (Aquifer) lsopach Map .................. 20
Extent of Glacial Deposits ............................................................... 23
Summary ................................................................................................... 23
CHAPTER 2: HYDROGEOLOGY ....................................................................... 28
Literature Review ...................................................................................... 28
Dakota Aquifer ................................................................................ 28

Fox Hills Aquifer ............................................................................. 29

Hell Creek Aquifers ......................................................................... 33
Glacial Deposit Aquifers ................................................................. 34

Data Analysis and Interpretation .............................................................. 35
Conceptual Physical System .......................................................... 35
Mathematical Statement ................................................................. 35
Parameter Values ........................................................................... 37

2-D Finite Difference Model ............................................................ 40
Simulation Results .......................................................................... 4O
Interpretation .................................................................................. 42
Summary ................................................................................................... 44
CHAPTER 3: HYDROGEOCHEMISTRY ............................................................ 46
Literature Review ...................................................................................... 46
Fox Hills Aquifer ............................................................................. 46

viii

 

 

Dakota Aquifer ................................................................................ 47
Data Analysis and Interpretation .............................................................. 48
Graphical Analysis .......................................................................... 48
Hydrochemical Facies .................................................................... 50
Chloride Distribution ....................................................................... 52
Average Linear Velocity from 36CI ................................................... 55
Summary ................................................................................................... 56
CHAPTER 4: STABLE ISOTOPE HYDROLOGY ............................................... 59
Literature Review ...................................................................................... 59
Atmospheric Waters ....................................................................... 59
Lake Waters ................................................................................ 60
Ice and Snow .................................................................................. 61
Ground Water ................................................................................. 61
Paleowaters .................................................................................... 62
Data Collection ......................................................................................... 63
Data Analysis and Interpretation .............................................................. 65
Summary ................................................................................................... 75
CHAPTER 5. POSSIBLE PALEOHYDROLOGIC RESPONSES TO
PLEISTOCENE GLACIATION ...................................................... 77
Literature Review ...................................................................................... 77
Glacial Meltwater Recharge Hypothesis ......................................... 77
Hydrology of Glaciers ..................................................................... 79
Data Analysis and Interpretation .............................................................. 83
ix

 

Simulation 1: present conditions ..................................................... 84

Simulation 2: Lake McKenzie ......................................................... 84

Simulation 3: blocked discharge area ............................................. 87

Simulation 4: subglacial recharge ................................................... 91
Interpretation ................................................................................ 101

Summary ................................................................................................. 101
SUMMARY AND CONCLUSIONS .................................................................... 104
Upgradient Aquifer Water ....................................................................... 104

Local Precipitation/Recharge .................................................................. 104

Local Precipitation during the Pleisotocene ........................................... 105
Leakage from Proglacial Lakes .............................................................. 106
Leakage from Adjacent Aquifers ............................................................. 107

Basal Meltwater ...................................................................................... 107
Conclusion and Recommendation .......................................................... 108
Appendix A. Geologic data ............................................................................... 1 10
Appendix B. Hydrogeologic data ...................................................................... 117
Appendix C. Hydrogeochemical data ................................................................ 122
Appendix D. Isotope data ................................................................................. 130
Appendix E. Paleohydrologic modeling data .................................................... 131
LIST OF REFERENCES ................................................................................... 147

.\'

 

 

LIST OF TABLES

Table 1. Stable isotope data from the discharge area of the Fox Hills aquifer... 72

Table 2. Estimation of subglacial recharge rates ................................................ 99
Table 3. Geologic data derived from drill logs .................................................. 110
Table 4. Water-level data for the Fox Hills aquifer ........................................... 117
Table 5. Input data for simulation of water levels in the Fox Hills aquifer ........ 118
Table 6. Hydrochemistry data for the Fox Hills aquifer ..................................... 122
Table 7. Isotopic analyses of collected water samples ..................................... 130
Table 8. Input data for simulation of water levels in the Fox Hills aquifer ........ 131
Table 9. Lake McKenzie simulation input data ................................................. 135

Table 10. Input data for simulation of Verone ice sheet blocking

the discharge area ....................................................................... 139
Table 11. Input data for simulation of Verone ice sheet recharging
the discharge area ....................................................................... 143
xi

 

 

 

 

LIST OF FIGURES

Figure 1. Location of study area in North Dakota ................................................. 4

Figure 2. Location and extent of the Williston basin (adapted from
Gerhard et al., 1982; Gerhard and Anderson, 1988) ......................... 8

Figure 3. Stratigraphic column for the Williston basin (adapted from
Carlson, 1982) ................................................................................. 11

Figure 4. Generalized bedrock geologic map of North Dakota
(Bluemle, 1988) ............................................................................... 15

Figure 5. Regional glacial history (Bluemle, 1984): a) pre—glacial drainage,
b) limits of Dunn and Verone glaciations ......................................... 16

Figure 5 (cont). 0) limit of Napoleon glaciation, d) limit of Phase D glaciation... 17

Figure 6. Subcrop map of the Fox Hills Formation ............................................. 21
Figure 7. Major glacial aquifers of the study area (adapted from

Randich, 1979; Ackerman, 1980) .................................................... 22
Figure 8. Fox Hills Formation sandstone thickness map .................................... 24
Figure 9. Extent of glacial deposits in the study area ......................................... 25

Figure 10. Fox Hills aquifer water levels in southwestern North Dakota

(adapted from Lobmeyer, 1985) ...................................................... 31
Figure 11. Conceptual model of the Fox Hills aquifer ......................................... 36
Figure 12. Water—level map of the Fox Hills aquifer ........................................... 38
Figure 13. Transmissivity map of the Fox Hills aquifer ....................................... 39

Figure 14. Finite-difference grid used for simulation of the Fox Hills aquifer ..... 41

xii

 

 

 

 

Figure 15.’

Figure 16.

Figure 17.

Figure 18.
Figure 19.
Figure 20.

Figure 21.

Figure 22.
Figure 23.
Figure 24.

Figure 25.

Figure 26.
Figure 27.
Figure 28.

Figure 29.

Figure 30.

Figure 31.

Figure 32.

 

Simulated water levels in the Fox Hills aquifer .................................. 43

Piper diagram of Fox Hills aquifer water in southwestern

North Dakota .................................................................................... 49
Hydrochemical facies map of the Fox Hills aquifer in

southwestern North Dakota ............................................................. 51
Chloride distribution in the Fox Hills aquifer ...................................... 54
Location of stable isotope water samples .......................................... 64
ZED-8180 relationship of the Fox Hills aquifer water samples .............. 66

Deuterium excess-5‘80 relationship of the Fox Hills aquifer

water samples .................................................................................. 68
80-8180 relationship by d-excess groupings ...................................... 69
Deuterium-excess values plotted with the chloride distribution ......... 7O
Mixing line of modern and paleowater ............................................... 74

Inferred groundwater flow directions during Pleistocene glaciation

(Downey, 1986) ............................................................................... 80
Schematic diagram of glacier hydrology (Lawson, 1993) .................. 82
Finite-difference grid for Fox Hills aquifer simulation ........................ 85
Simulated water levels in the Fox Hills aquifer .................................. 86

F mite-difference grid for simulating the influence of
proglacial Lake McKenzie ................................................................ 88

Simulated water levels, taking into account Lake McKenzie ............. 89

F mite-difference grid for simulation of the Verone ice sheet

partially blocking the discharge area ............................................... 90
Simulated water levels, taking into account the partially
blocked discharge area ................................................................... 92
xiii

Figure 33. Schematic diagram of a glacier advancing over an escarpment

(after Bluemle, 1977) ....................................................................... 93
Figure 34. Linked cavity drainage system (Kamb, 1977): a) map view,

b) cross-section ............................................................................... 94
Figure 35. Modified transmissivity distribution .................................................... 95

Figure 36. Finite-difference grid for simulation of the Verone ice sheet
contributing recharge ....................................................................... 97

Figure 37. Simulated water levels, taking into account recharge from
the Verone ice sheet ...................................................................... 100

xiv

 

 

 

INTRODUCTION

Statement of the Problem

Various researchers have suggested that groundwater flow patterns of
certain aquifers may have been altered during the Pleistocene because glacial
ice blocked the aquifers’ regional discharge areas, subglacial meltwater was
available for recharge, and adjacent geologic materials were compressed under
the weight of overriding ice sheets. Ice sheets tend to move toward
topographically low areas, which often are regional discharge areas.
Groundwater discharge becomes blocked by the overriding ice sheet, resulting
in altered and possibly reversed groundwater flow patterns; hence, temporary
recharge of an aquifer may occur in the discharge area if a hydrologic
connection between subglacial water and ground water is established.

The purpose of this study is to investigate the response of a regional
aquifer system to Pleistocene glaciation and, in particular, the possibility of
temporary recharge in the discharge area. This investigation involves identifying
potential water sources for the discharge area of a regional aquifer as a set of
multiple-working hypotheses. The potential sources/multipIe-working
hypotheses are:

a) upgradient aquifer water
b) local precipitation/recharge
c) local precipitation during the Pleistocene

d) leakage from proglacial lakes

1

 

 

 

2

e) leakage from adjacent aquifers/aquitards

f) subglacial meltwater
or a combination of (a) through (f). Each working hypothesis will be tested in
this study as a means of identifying the source(s) of the water in the discharge

area.

The Test Aquifer

Prior to choosing a regional aquifer with which to investigate the
paleohydrological response Of continental glaciation, criteria for choosing an
aquifer are outlined in terms of the characteristics of an ”ideal" test aquifer.
First, an ideal test aquifer should have support in the literature for the possibility
of glacial influences during the Pleistocene. Second, it should be of regional
extent, with a discharge area that has been overridden, ideally, by a single
glacial advance while the main portion of the aquifer remained ice free. Third, it
should crop out in the discharge area, thereby allowing a direct hydrologic
connection between the subglacial water and the aquifer. Fourth, the water
chemistry should exhibit the presence of a separate freshwater body in the
discharge area, representing the recharged glacial meltwater.

Because the Fox Hills aquifer of south-central North Dakota meets the
above criteria, it is uniquely suited for this investigation. The Fox Hills aquifer is
part of the Northern Great Plains Aquifer System (NGPAS) and Downey (1986)
suggests that groundwater flow patterns may have been altered in the system
due to Pleistocene glaciation. He also suggests that the regional discharge area
of the system may have been temporarily recharged with meltwater—-the first
criterion. Since the Fox Hills aquifer is the stratigraphically highest regional

aquifer in the system, it is also the aquifer most likely to be influenced by

 

3

glaciation in this region. Although, two glacial advances (rather than one) have
been documented in the Fox Hills aquifer discharge area in south-central North
Dakota, the second criterion is met, though not completely. These ice sheets
covered only the discharge area, allowing normal flow patterns to continue in the
main portion of the aquifer. The Fox Hills aquifer also meets the third criterion,
because the aquifer crops out in its discharge area in south-central North
Dakota. Furthermore, the water chemistry in the discharge area is not
representative of the upgradient water chemistry—the fourth criterion.

The study area is located in south-central North Dakota, west of the
Missouri River, and includes Sioux, Grant, and Morton counties (Figure 1).
Information for Emmons County (east of the Missouri River and adjacent to
Sioux County) and Carson County, South Dakota (south of Sioux County) are

included where it aids understanding of the hydrogeologic system.

Investigative Techniques

Hydrogeologic, hydrogeochemical, isotopic and modeling approaches are
combined to investigate the effect of glaciation on the Fox Hills aquifer.

Geology. The geologic investigation presented in Chapter 1 sets the
stage for subsequent investigative techniques and includes (1) mapping the Fox
Hills Formation subcrop, (2) mapping the sandstone thickness of the Fox Hills
Formation, and (3) estimating the extent of glacial deposits using drill logs.

Hydrogeology. The hydrogeologic investigation presented in Chapter 2
includes (1) mapping the water-levels in the Fox Hills aquifer, (2) mapping the
distribution of aquifer transmissivity, and (3) simulating present flow conditions in

Sioux, Grant, and Morton counties using a 2-dimensional finite difference

 

 

- - -' -.-'=..i.l~qt"=-.;-:u.-.Jc need

"I ' '2‘”. . _. l . - \-

 

.90me 562 5 meta >38 “6 c0283 9 930E

wI<O wv_(4

    
 

<w>><x<x<m
wx<4

 

 

 

5

groundwater flow model to assess possible recharge to the discharge area.
Hypotheses (b) and (e) are tested in Chapter 2.

Hydrogeochemistry. The hydrogeochemical investigation is presented in
Chapter 3 and includes (1) graphically analyzing water chemistry data using the
Piper trilinear diagram method, (2) mapping the hydrochemical facies distribution
in southwestern North Dakota and discussing the chemical evolution of the water
types, (3) mapping the chloride distribution in southwestern North Dakota and
discussing possible origins for different zones, and (4) calculating average linear
velocity from 36Cl data. Hypotheses (a), (b) and (e) are tested in Chapter 3.

Stable Isotopes. The stable isotope investigation presented In Chapter 4
includes ( 1) plotting the groundwater data on a 60—6180 graph and comparing
their distribution with the North American and local (Oakes, North Dakota)
meteoric water lines to assess the influence of fractionating processes (e.g.,
evaporation), (2) calculating the deuterium excess of the samples to indicate the
presence of paleowaters in the discharge area, (3) plotting the deuterium—excess
values on the chloride distribution map to indicate the geographical distribution
of different recharge waters, and (4) calculating the mean annual air temperature
of the samples to indicate past climatic conditions. Hypotheses (b) through (d),
and (f) are tested in Chapter 4.

Paleohydrologic Responses. Investigation of the paleohydrologic
responses of the Fox Hills aquifer to Pleistocene glaciation is presented in
Chapter 5 and includes (1) simulating the influence of proglacial lakes on the
flow regime in Sioux, Morton, and Grant counties using a 2-dimensional finite
difference groundwater flow model, (2) simulating the hydrologic response of the
Fox Hills aquifer to a discharge area partially blocked by glacial ice, (3)
estimating the amount of leakage that could have occurred beneath the

Laurentide ice sheet in Sioux and Morton counties, and (4) simulating the

 

 

 

6

hydrologic response of the Fox Hills aquifer to recharge under the glacial ice.

Hypotheses (c), (d), and (f) are addressed in Chapter 5.

Potential Significance

The results of this study have the potential to increase our understanding
of the influence of continental glaciation on groundwater flow patterns and to
explain water chemistry anomalies in some aquifers. Continental ice sheets
extended over much of the northern hemisphere during the Pleistocene and may
have significantly altered groundwater flow paths and recharge locations of
regional bedrock aquifers at several locations. Thus, present conceptual models
of groundwater flow systems that do not take Into account the potential influence
of ice sheets may result in misinterpretation of a system's dynamics and poor

prediction of its future behavior.

 

 

 

 

CHAPTER 1: GEOLOGY

Literature Review

Since the Fox Hills aquifer is situated in the Williston basin, the basin's
formation and structure are discussed. In addition, the basin's subsurface
stratigraphy is outlined to provide a framework for understanding the
hydrostratigraphy of the upper units. Near-surface hydrostratigraphic units and
the area's glacial history are then presented as a basis for all further
discussions.

The Williston Basin: Formation and Structure. The Williston basin is a
Phanerozoic sedimentary basin that extends across North Dakota, South
Dakota, eastern Montana, southern Saskatchewan, and southwestern Manitoba
(Figure 2). The center of the 130,000 km2 basin is located in northwestern North
Dakota, where sediment thickness is approximately 5 km (Anna, 1986). Initial
subsidence of the basin occurred by Early Ordovician and was apparently
unrelated to tectonic activity in North America (LeFever et al., 1987), although
this is not generally agreed on (Gerhard et al., 1982). The basin may have
originated as a craton—margin or a continental-shelf basin changing to an
intracratonic basin in response to the Cordilleran orogen and crustal accretion to
the west (Gerhard and Anderson, 1988). The eastern boundary of the basin, or
hingeline, coincides with the boundary between the Churchill (Trans-Hudson)
and Superior provinces (Gerhard and Anderson, 1988). Figure 2 shows the
Sioux Arch, Black Hills Uplift, Cedar Creek Anticline, and Bowdoin Dome,
bounding structures of the Williston basin (Gerhard and Anderson, 1988).

Thomas (1974, 1979) studied the regularity of surface lineaments in the

Williston basin. He mapped lineaments using both surface and subsurface data

7

 

 

Alberta saSkatCherwan

Manitoba

Williston
Basin

Minnesota

Montana

Creek
Anticline

Nebraska

0 100 200 miles

I—’—r—l—r——"

0 100 200 kilometers

Figure 2. Location and extent Of the Williston basin

(adapted from Gerhard et al., 1982; Gerhard and Anderson, 1988).

 

 

 

 

9

and identified two main directions of lineament trends—NE and NW. Thomas
interpreted the lineaments as representing zones of weakness bounding
Precambrian basement blocks. Recent work has indicated that two
perpendicular sets of lineaments are imprinted on the Rocky Mountains and
adjacent parts of the Great Plains. The main system trends N30-40W/N50—60E
and a secondary system trends N5—15E/N75-85W (Maughan and Perry, 1986).
Gerhard et al. (1982) suggest that the basement blocks in the central Rockies,
the Black Hills, and the Williston basin were formed by left-lateral shearing along
the Fromberg and Colorado-Wyoming lineaments (shear zones; Figure 2).
These authors also suggest that subsequent stresses from orogenic activity of
the North American plate produced periodic vertical motion along basement
zones of weakness.

This recurrent movement of the basement blocks throughout the
Phanerozoic Eon influenced sedimentation in the basin (Shurr, 1979; Anna,
1986) by controlling the physical characteristics of sediment and facies
distribution. Recurrent movement of basement blocks also deformed overlying
sediments by faulting and folding. Movement occurred primarily along the
NE/NW system of lineaments, but the ME system also produced important
Laramide structures (Maughan and Perry, 1986).

Subsurface Stratigraphy. Crystalline rocks of Precambrian age form the
basement in the Williston basin. The basin lies between the Superior and
Wyoming provinces of Archean age. The Superior province belonged to a
subducting plate during early Proterozoic convergence, and the Wyoming
province belonged to the overriding plate (Hoffman, 1989). The Trans-Hudson
orogen between the two provinces consists of juvenile Proterozoic crust

including island arcs and obducted oceanic crust (Hoffman, 1989).

 

 

 

 

10

The sedimentary rocks of the Williston basin depict a history of repeated
marine transgressions and regressions. The North American sedimentary-rock
record has been divided into six cratonic sequences, with each sequence
representing a major transgressive-regressive cycle bounded by craton-wide
unconformities (Sloss, 1963). All six sequences (Sauk, Tippecanoe, Kaskaskia,
Absaroka, Zuni, and Tejas) are present in the Williston basin (Figure 3).

The Sauk Sequence is represented by the Deadwood Formation of Upper
‘ Cambrian to Lower Ordovician age formed during a marine transgression from
the west. The onlap depositional sequence consists of a basal sandstone
overlain by shale and carbonate and an upper sandstone (Carlson, 1982; 1983;
Bluemle, 1984).

A second marine transgression is recorded by the Tippecanoe Sequence
of Middle Ordovician to Silurian age. The Williston basin began to be a slightly
negative (topographically) area over which an extensive epicontinental sea
invaded from the south and east. Initially clastics (Winnipeg Group) were
deposited, followed by carbonates and minor amounts of evaporites and shales
(Carlson, 1982; 1983; Bluemle, 1984).

The Kaskaskia Sequence consists of shallow-water carbonates and thin
shales deposited by a transgressive sea from the north and west during
Devonian time, and fine-grained clastics (Baaken Formation), carbonates and
evaporites (Madison Group), and clastics and carbonates (Big Snowy Group)
deposited in a second transgressive sea during Mississippian time (Carlson,
1982; 1983; Bluemle, 1984).

Deposits from an early Pennsylvanian transgression marks the beginning
of the Absaroka Sequence. Clastics, carbonates, and evaporites were

deposited through Triassic time (Carlson, 1982; 1983; Bluemle, 1984).

 

 

 

ll

 
 
   

' FORMATION
I'm-

   
  

 
   

 

   
    
     

   
       

   
  

   

9 "III "II"
3 III-_
9 .ummr z
u sinsnmzll
U EIIEIIIII
~=ammIIII
Inn-III
-I'IT!|I'T::-
§§Enmllll
CRETACEOUS S‘W
80%
-URA$SI(‘
=IIIII|IlllIlIIllllllllIllllllll III-Ill|l|||lll|llllllllllllllllllllll
_muN I Ilzmlllll
“W0“ 3-;
g-lnmIIIII
ummmmwmmmmwwwwmwmm
mm-
“mmmw Emmi-II
EEEEEI-
lmanIIl
KASKASKIA m
ImmnanI
“WW
9 IzmnIIII
.3 mm:-
§ _ llllllllllllllllllllllllllllllll IllllllllllllllllllIllllIlllIIIlIlIl
(
‘ IMMEDI-
MOUNTAIN
nmwoc
omevrcux 25m
géifiéiiii
i-o
Iwwmmmwmmmmmmummwm
m

I'KI‘.1 ANItKIAN “I I. K\

 

      
 

    

  
 

 

FORMATION MEMBER

 

 
 

W/m
7!! mill/III]—
'I’ft'l'ffz'l/I/I/A—
“flatm—
sew—

' «5:-

[at
—

 
   
    
   

 
   
   
 

    

fitt’eiréastl - €33.22:

  

    

Figure 3. Stratigraphic column for the Williston basin

(adapted from Carlson, 1982).

 

 

 

12

The Zuni Sequence consists primarily of clastics. A marine transgression
from the west deposited redbeds, evaporites, and carbonates during Middle
Jurassic time. Following a Late Jurassic-Early Cretaceous regression, Early
Cretaceous seas invaded, resulting in the non-marine to marine lnyan Kara
Formation. Thick deposits of marine shale formed before the sea regressed,
leaving behind the fine sands of the marine Fox Hills Formation and non~marine
Hell Creek Formation, and the lignite-bearing Fort Union Group (Carlson, 1982;
1983; Bluemle, 1984).

The Tejas Sequence consists largely of fluvial, lacustrine, and glacial
deposits. No marine deposits are found in North Dakota that belong to this
sequence (Carlson, 1982; 1983; Bluemle, 1984).

Hydrostratigraphic Units. The Lower Cretaceous lnyan Kara Group
(Figure 3) comprises a regional aquifer (Dakota aquifer) that is found at depths
from 670 m (2,200 ft) in southeastern Emmons County to 1490 m (4,900 ft) in
northwestern Morton County. The lnyan Kara consists of sandstone (15 to 53 m
thick; 50 to 175 ft thick) and shale, and is of variable thickness. The lower unit,
the Lakota Formation, is comprised of non-marine sandstones and mudstones,
which are overlain by marine shale (Fuson Formation) and marine sandstone
and shale (Fall River Formation). The contact between the lnyan Kara and Skull
Creek Formations is gradational. The Skull Creek Formation is a marine shale,
23 to 84 m (75 to 275 ft) thick (Armstrong, 1978; Carlson, 1982, 1983; Bluemle,
1984; Downey, 1986).

The Newcastle Formation consists of a muddy sandstone with localized
zones of clean sandstone up to 18 m (60 ft) thick. This formation is absent in
parts of Sioux, Morton, and Grant counties. In Emmons County the Newcastle
Formation contains very fine grained sandstone (Carlson, 1982, 1983; Bluemle,

1984).

 

 

 

13

The remaining Cretaceous sediments below the Fox Hills Formation
(Figure 3) consist of marine shales, some of which are calcareous and/or contain
bentonitic beds. These marine formations include the Mowry, Belle Fourche,
Greenhom, Carlile, Niobrara, and Pierre formations, collectively ranging from
488 to 838 m (1,600 to 2,750 ft) in thickness (Carlson, 1982, 1983; Bluemle,
1984).

The Pierre Formation crops out in southeastern Sioux County and
southwestern Emmons County, as well as, subcrops along preglacial and
interglacial valleys. It consists of dark-gray to black siliceous shale, siltstone,
and thin layers of bentonite. The formation is generally considered
impermeable; however, locally the Pierre Formation yields water from shallow
(about 1 m) fracture zones (Armstrong, 1978; Carlson, 1982, 1983; Bluemle,
1984).

The Upper Cretaceous Fox Hills Formation is a marine-to brackish-water
deposit of sandstone and shale, variously subdivided into three or four
members. For the purpose of this study a four-member division will be used
following Carlson (1983; Figure 3). The lowest member is the Trail City which
consists of silty to sandy shale that conformably overlies the Pierre Formation
with a gradational contact. The Trail City Member is only a meter (few ft) thick.
The Timber Lake Member is predominantly sandstone that thins westward from
about 53 to 15 m (175 to 50 ft). The Bullhead Member consists of interbedded
sand and shale generally 30 m (100 ft) thick. The Colgate Member consists of a
well indurated white sandstone up to 18 m (60 ft) thick (Carlson, 1982, 1983;
Bluemle, 1984).

The Fox Hills Formation crops out along the Cannonball River in
southeastern Morton County, throughout much of central Emmons County, and

in eastern Sioux County. It also subcrops in most of the remainder of Emmons

 

 

 

 

14

County. The formation is absent in parts of central and southeastern Emmons
County and southeastern Sioux County, where it has been eroded (Figure 4).
The formation dips to the northwest and reaches depths in excess of 457 m
(1500 ft) in northwest Morton County. The Fox Hills aquifer is comprised of the
Colgate Member in Sioux, Morton, and Grant counties and the Colgate and
Timber Lake members in Emmons County (Armstrong, 1978; Randich, 1979;
Ackerman, 1980; Carlson, 1982, 1983; Bluemle, 1984).

The Late Cretaceous Hell Creek Formation conformably and gradationally
overlies the Fox Hills Formation. It is generally accepted that the Pierre, Fox
Hills, and Hell Creek formations were deposited concurrently. The Pierre
represents a deeper water marine environment, the Fox Hills a transitional
environment, and the Hell Creek a continental environment. The Hell Creek
Formation consists of sandstone, siltstone, mudstone, carbonaceous shale, and
lignite. Although the Hell Creek Formation is predominantly a non-marine
deposit, a thin marine tongue of the formation occurs in Sioux, Morton, and
western Emmons counties. The sandstones typically contain bentonitic beds
less than 2 m (6 ft) thick that occur in the upper section of the formation. The
formation is present in western Emmons County and on some butte tops in
central Emmons County. It also crops out in central Sioux County, eastern Grant
County, and southeastern Morton County. The formation dips to the northwest
and reaches a depth of nearly 366 m (1200 ft) in northwest Morton County. The
sandstone units, which serve as local aquifers, are generally not laterally
extensive (Ackerman, 1980; Carlson, 1982, 1983; Bluemle, 1984).

Glacial History. Prior to Pleistocene glaciation, south-central North
Dakota’s land surface was drained to the northeast by the ancestral Cannonball
River system (Figure 5a; Bluemle, 1984). When glacial ice advanced from the

northeast, this drainage was blocked and diverted southward along the margin of

 

 

 

15

.8me .oEmEmv 90me 562 so amE 0506mm x0868 nouficmcoo .v 939m

859. 21.5255... um I
9.09. 252.55.: c D

mzucz 0.55:: _ ”—

:o:x=:CL nit-U ex D

5:555. 55:22 5. D
Eta—=5“. 2Z5 ax D :csfiEc... 351:1. E. D
=c:..E._cn_ £3. 5.“. E D cc:§.:c.._ zap—5250 u._ D
.5:E:_:.._ quU=u .2 D cozeEEL 2.5m a: D

2.”... mku. m30ub<

3:209

_
llIIrII.

.mm .m 732:.

:iieuc Sufi m£fl< .ecacuv=< .= >965
3?...“ 12.8133 :51: £32

2535 .n. 5.2
.3
59:3 :50: do “is. 05380 595%. 35:52.5

SSS—SE {SU .553: a... D
:EEEE; 2.2: ZEEum 5 B
5:25.... 3:; 53:0 u... D

c:o.0 5...: 2...? >.._ D

2“.— _m>m >11. . 2....

«no.
mm as Z v3.2.2.3! 2

 

 

 

 

16

MERCER

MORTON

NORTH DAKOTA
SOUTH DAKOTA

RA/
NORTH DAKOTA

SOUTH DAKOTA

 

Figure 5. Regional glacial history (Bluemle, 1984):
a) pre—glacial drainage, b) limits of Dunn and Verone glaciations

 

 

 

l7

STUTSMAN

LOGAN

”Mm
NQBIH DAKOTA
SOUTH DAKOTA

I
In. ‘ ucpnsn u
CORSCN (

MERCER

 

Figure 5 (con’t). 0) limit of Napoleon glaciation, d) limit of Phase D glaciation.

 

 

17

STUTSMAN

“km
NORTH DAKOTA

l‘,C PNER Cl

MERCER

NORTH DAKOTA
SOUTH DAKOTA

 

Figure 5 (con’t). C) limit of Napoleon glaciation, d) limit of Phase D glaciation.

 

 

 

18

the glacier. The oldest recognized ice margin in North Dakota has been
designated the Dunn Ice Margin (Figure 5b, dotted line) and may represent
several glacial advances that are collectively called the Dunn Glaciation or
Phase A (Clayton, 1969; Clayton and Moran, 1982; Bluemle, 1984). The Dunn
Glaciation is presumed to be pre-Wisconsinan in age and to have had a
northeastern source (Clayton and Moran, 1982; Bluemle, 1984).

The second recognizable ice margin in south-central North Dakota is
designated the Verone Ice Margin (Figure 5b). It had a northern source and may
be either late pre-Wisconsinan or Early Wisconsinan in age (Clayton and Moran,
1982; Bluemle, 1984). The Verone Glaciation may represent a composite of
several glacial pulses (Bluemle, 1984). Drainage from Montana, Wyoming,
Alberta, and Saskatchewan was diverted southeastward through a major trench,
the Killdeer-Shields Diversion Channel. This trench, situated along the Verone
lce Margin, joined the Missouri River 25 km (14 miles) north of the South Dakota
border either following the modern Missouri River or continuing southeastward
along the Cat Tail Creek Channel (Figure 5b; Clayton and Moran, 1982;
Bluemle, 1984). interbedded lake and fluvial sediments indicate the formation of
proglacial lakes during the Verone Glaciation, also known as Phase B (Clayton
and Moran, 1982; Bluemle, 1984).

Following the Verone Glaciation, a long period of erosion occurred that
removed much of the glacial sediment and resulted in the re-establishment of a
northeastward drainage system along the ancestral Cannonball River (Bluemle,
1984). The next documented glacial advance, the Napoleon Glaciation or
Phase C, most likely occurred during Early Wisconsinan time (though it could
have occurred pre—Wisconsinan or Late Wisconsinan) and had a northern
source (Clayton and Moran, 1982; Bluemle, 1984). The Napoleon lce Margin

generally coincides with the Missouri River in south-central North Dakota (Figure

 

 

 

19

5c), crossing the river in southeastern Morton County. Bickley (1972) suggests
that the Napoleon ice was clean, producing thin deposits. Westward drainage
east of the Missouri River was probably established at this time, although
subsequent glaciations enhanced it (Bluemle, 1984).

Following the retreat of the Napoleon Glaciation, a long period of erosion
occurred that removed most of the glacial sediment and exposed bedrock over
much of Emmons County (Bluemle, 1984). The first recognizable Late
VWsconsinan ice margin in North Dakota (Phase D) is dated at 25 ka to 20 ka
(Clayton and Moran, 1982). The ice sheet was most likely in its wasting stage
when it reached south-central North Dakota, as it split into two lobes (Figure 5d)
on encountering a gentle topographic high in Logan and McIntosh counties
(Bluemle, 1984). Drainage was probably first diverted southeastward along the
Strasburg Channel until it was blocked by the advancing ice sheet, resulting in a
proglacial lake, Lake McKenzie (Bluemle, 1984). Another glacial lake formed
when ice blocked the Missouri River in north-central South Dakota (Bickley,
1972). Lake Standing Rock may have occupied southeastern Sioux and
southwestern Emmons Counties during Late Wisconsinan time (Bluemle, 1984).

Clayton and Moran (1982) have suggested the following ages for the first
four recognized glacial events in North Dakota: Dunn Glaciation, pre-
Wisconsinan; Verone Glaciation, late pre-Wisconsinan to Early Wisconsinan;
Napolean Glaciation, pre-Wisconsinan, Early Wisconsinan, or Late
Wisconsinan; and Phase D, Late Wisconsinan, 25 ka to 20 ka years ago. These
ages may be compared to the ages of four periods of loess deposition in the
Missouri and Mississippi river valleys recently identified by Forman et al. (1992)
using thermoluminescence and 14C. Periods of loess deposition have been

associated with advances of the Laurentide Ice Sheet into the headwaters of the

 

 

20

Missouri and Mississippi rivers (Johnson and Follmer, 1989) and may span all or
part of a glacial/deglacial cycle (Ruhe, 1983).

The four periods of loess deposition are ca. 135:20 ka (lllinoian), 85-70
ka (Early Wisconsinan), 45-30 ka (Middle Wisconsinan), and 25-12 ka (Late
Wisconsinan). The inferred ages of glaciation parallel the deglaciation record Of
the Laurentide Ice Sheet determined from chronologic and stratigraphic studies
in the Hudson Bay Lowlands (Forman et al., 1992). Four periods of deglaciation
culminating at ca. 130, 64, 35, and 8 ka have been identified. Although the ages
of the inferred Laurentide glaciations cannot be applied to the North Dakota

glacial events without further study, they do provide a frame of reference.

Data Analysis and Interpretation

Fox Hills Formation Subcrop Mag. Lithologic logs for 294 test holes
drilled in Sioux, Grant, and Morton counties by the North Dakota State Water
Commission (Randich, 1975; Ackerman, 1977) were examined to prepare a
subcrop map of the Fox Hills Formation. The resulting map (Figure 6; Appendix
A) shows the Fox Hills Formation subcropping further west than is suggested by
published geologic maps of the area (Carlson, 1982; 1983). The Fox Hills
Formation subcrops along ancestral bedrock valleys buried by glacial deposits
and identified by the glacial aquifers which occupy them. The Shields, Little
Heart, Elm Creek, and St. James glacial aquifers (Figure 7) directly overlie the
Fox Hills Formation in Sioux, Grant, and Morton counties.

Fox Hills Formation Sandstone (Aguifer) lsopach Mag. Lithologic logs for
42 test holes drilled by the North Dakota State Water Commission in Sioux,
Grant, Morton counties (Randich, 1975; Ackerman, 1977) were examined to

prepare a sandstone isopach map of the Fox Hills Formation. Many of the test

 

21

EXPLANATION

  
  
  
 
  
 

D Fox Hills Fm subcrop
Fox Hills Fm absent

SYMBOLS (boreholes)
A Fox Hills Fm overlain

A 0 Fox Hills Fm subcrops
’ ' + Fox Hills Fm absent

0 3 6 12 leiIes
p—q—q—y—a—Fd
o 5 lo 15 20 25kllomeleu

Figure 6. Subcrop map of the Fox Hills Formation.

 

 

22

 

O 3 6 12 IBmiles
b—h—fi—FJFFd
O 5 10 I5 20 25kilomelers

Figure 7. Major glacial aquifers of the study area
(adapted from Randich, 1979; Ackerman, 1980).

 

 

23

holes have qualitative geophysical logs (primarily potential and resistance) that
aided in identifying and determining the thickness of permeable sandstone units
(Appendix A). A map was produced using the drill log data as input to SURFER,
a contouring program. The kriging method was used to calculate sandstone
thicknesses for a 26 x 26 grid covering the three county study area. The
resulting map is shown as Figure 8. Sandstone thicknesses range from O to
41.8 m.

Extent of Glacial Deposits. Lithologic logs for 294 test holes drilled in
Sioux, Grant, and Morton counties by the North Dakota State Water Commission
(Randich, 1975; Ackerman, 1977) were examined to determine the extent of
glacial deposits in the study area. The resulting map (Figure 9; Appendix A)
shows that glacial deposits occur west Of the Killdeer-Shields Diversion Channel
(Verone Glaciation) in southeastern Sioux and Grant counties. These western
deposits are attributed to the Dunn Glaciation based on location. The remainder
of the glacial deposits in Sioux and Grant counties were deposited during the
Dunn and Verone Glaciations and Phase D (Lake Standing Rock sediments),
while those in Morton County were deposited during the Dunn, Verone, and

Napolean glaciations and Phase D (Lake McKenzie sediments).

Summary

The Upper Cretaceous Fox Hills aquifer is situated in the Williston basin,
a Phanerozoic sedimentary basin that extends across North Dakota, South
Dakota, eastern Montana, southern Saskatchewan, and southwestern Manitoba.
The Fox Hills Formation is a marine—to brackish—water deposit of sandstone and
shale. lt crops out along the Cannonball River valley in southeastern Morton

County and along the Missouri River

 

 

24

 

C|:6m SD

0 3 6 12 lemiles
hip—1W
0 5 1015 20 25kilomelers

Figure 8. Fox Hills Formation sandstone thickness map.

 

 

25

   
 
  
  

  

EXPLANATION

 

3' \.'° .‘T'°°°' '°7"°
~ O‘.°o'°o'

  

OO'Q.|“." ..‘ . . .)
-.

g.

[‘12] extent of glacial deposits
determined from drill logs

  

a
0
- t
\
u
‘

SYMBOLS (boreholes)

   
 

glacial deposits present
glacial deposits absent

0 3 6 l2 leiIes
o 5 10 I5 20 25kilomelers

Figure 9. Extent of glacial deposits in the study area.

 

 

 

26

valley in eastern Sioux and western Emmons counties. The formation is absent
in parts of southeastern Sioux and western Emmons counties, where it has been
eroded.

The first regional aquifer below the Fox Hills Formation occurs in the
Lower Cretaceous lnyan Kara Group (Dakota aquifer). Conformably underlying
the Fox Hills Formation is the Pierre Formation, which is generally considered
impermeable. The Late Cretaceous Hell Creek Formation conformably overlies
the Fox Hills Formation. Its sandstone units serve as local aquifers that are
generally not laterally extensive.

Four glacial advances are recognized in south-central North Dakota. The
Dunn and Verone glaciations crossed the present Missouri River overriding
outcrops of the Fox Hills Formation in Emmons, Sioux, and Morton counties.
The Napoleon Glaciation extended across the present Missouri River in
southeastern Morton County overriding outcr0ps of the Fox Hills Formation in
Emmons County. The Late Wisconsinan, Phase D, glaciation overrode outcrops
of the Fox Hills Formation in south-central Emmons county and blocked the
Strasburg Channel forming Lake McKenzie, which covered Fox Hills Formation
outcrops in Morton, Sioux, and Emmons counties. A southern ice advance
across the Missouri River trench formed Lake Standing Rock, inundating
outcrops of the Fox Hills Formation in Sioux and Emmons Counties.

Lithologic logs for 294 test holes drilled in Sioux, Grant, and Morton
counties by the North Dakota State Water Commission were examined to
prepare a subcrop map of the Fox Hills Formation and to determine the extent of
glacial deposits in the study area. The Fox Hills Formation subcrops along
ancestral bedrock valleys buried by glacial deposits and extends further west
than is suggested by published geologic maps of the area. Lithologic logs for 42

test holes drilled by the North Dakota State Water Commission in Sioux, Grant,

 

27

Morton counties were examined to prepare a sandstone isopach map of the Fox

Hills Formation.

 

 

 

CHAPTER 2: HYDROGEOLOGY

Literature Review

The hydrogeology of the Fox Hills aquifer and adjacent aquifers will be
reviewed. The underlying Dakota aquifer will be discussed first, then the Fox
Hills aquifer, and finally the overlying Hell Creek aquifers and glacial deposit
aquifers.

Dakota Aguifer. The water—bearing sandstones of the lnyan Kara Group
form the lower part of the Dakota aquifer. The hydraulic conductivity and
transmissivity of the lnyan Kara ranges from 6 to 18 mid and 500 to 1200 mm,
respectively, in south-central North Dakota (Butler, 1984). The porosity of the
lnyan Kara sandstones vary from 30 to 35 percent in eastern North Dakota to
less than 20 percent basinward. The potentiometric surface of the lower Dakota
aquifer shows a potential high is located in south-central North Dakota, with
head values ranging from 549 to 671 m (1800 to 2200 ft).

The Newcastle Formation forms the upper part of the Dakota aquifer in
eastern North Dakota. Distribution of the Newcastle Formation is erratic in
Sioux, Grant, and Morton counties (Carlson, 1982; 1983). Where present,
sandstones may be up to 18 m (60 ft) thick. In Emmons County, the Newcastle
sandstones are very fine grained, resulting in low yields (Armstrong, 1978).

A three-dimensional flow model of the Dakota aquifer in North Dakota
indicates that leakage into and out of the Dakota is necessary to achieve a
reasonable simulation Of observed head values (Butler, 1984). Butler’s flow
model indicates leakage into the Dakota aquifer through the upper confining
layer occurs in the western third of the state, while the model indicates leakage

out of the aquifer through the upper confining layer for the eastern two-thirds.
28

 

9--

29

The modeled vertical hydraulic conductivity for the upper confining layer varied
from 1.5 x 10-10 to 2.4 x 10‘8 mls, with the lower value predominating in the lower
Missouri River valley of south-central North Dakota. The vertical hydraulic
conductivity of the confining layer in south-central North Dakota is six orders of
magnitude smaller than the hydraulic conductivity of the Dakota aquifer. The
model simulated heads within a standard deviation of 15 m. In south-central
North Dakota, calculated head values differed from observed heads by up to 15
m along the Missouri River to as much as 55 m just west of the river.

Bredehoeft, et al. (1983) used four different conceptual models to
simulate groundwater flow in the Dakota aquifer in South Dakota. The results of
their simulations indicate that prior to development most of the recharge to and
discharge from the Dakota aquifer occurred as leakage through confining layers.
The hydraulic conductivity Of the Dakota aquifer was assigned as 1.7 mld. All
models yielded similar values for the vertical hydraulic conductivity of the
overlying confining layer-~15 x 10'11 and 6.1 x 10-11 m/s. These values are
within one order of magnitude of the vertical hydraulic conductivity value
determined by Butler (1984) from the North Dakota model. The steady—state
upward leakage through the confining layer was calculated to vary from 0 to <1.5
x 10'11 m/s (<0.47 mm/yr) in north—central South Dakota. The hydraulic
conductivity values for the upper confining layer computed by the regional flow
models were significantly higher than those determined from in situ and
laboratory tests, suggesting that much of the flow through the confining layer
occurs as fracture flow (Bredehoeft, et al., 1983).

Fox Hills Aguifer. In eastern Montana and western North Dakota, the
sandstones of the Fox Hills and lower Hell Creek formations form a continuous
sandstone sequence that has been termed the Fox Hills-basal Hell Creek

aquifer (Thorstenson et al., 1979). In south-central North Dakota, the

 

30

sandstones of the Fox Hills and Hell Creek formations are separated by siltstone
and bentonitic shale and are thus treated as separate aquifers (Ackerman,
1980). The hydraulic conductivity of the Fox Hills aquifer varies widely with core
sample values ranging from 3.6 x 105 to 33 m/d (Randich, 1979; Ackerman,
1980). The geometric mean of ten samples in Morton County was 0.20 m/d
(Ackerman, 1980). The mean for Sioux and Grant counties was 0.57 mld
(Randich, 1979). Hydraulic conductivity values determined from flow and
recovery tests in Mercer and Oliver counties (north of Morton County) range
from <0.04 to 4.8 m/d with a mean of 0.6 m/d (Croft and Wesolowski, 1970).

Transmissivities calculated from slug tests in Sioux and Grant counties
range from 1.7 to 12.5 m2ld with a mean of 5.2 mzld (Randich, 1979).
Transmissivities estimated from sandstone thickness and hydraulic conductivity
values for Emmons and Morton counties range from 2 to 40 m2ld (Armstrong,
1978; Ackerman, 1980). Porosity values range from 35 to 53 percent in Sioux,
Grant, and Morton counties (Randich, 1979; Ackerman, 1980).

The Fox Hills aquifer is recharged along the Cedar Creek anticline in
southeastern Montana and southwestern North Dakota where the aquifer crops
out, and by leakage from overlying aquifers in southwestern North Dakota.
Groundwater flow is generally to the east and northeast (Figure 10). Two
regional discharge areas occur in western North Dakota. The Missouri River
valley is the main regional sink for the Fox Hills and overlying aquifers (Downey,
1986). The
Little Missouri River valley also serves as a regional discharge area, although of
lesser regional extent (Hamilton, 1970).

The main discharge area occurs along the Missouri and Cannonball river
valleys in Sioux and Morton counties, where the Fox Hills aquifer crops out and

contributes discharge to surface flow (Randich, 1979; Ackerman, 1980).

 

 

 

 

 

32

Discharge also occurs by upward leakage into overlying aquifers along the
Missouri and Knife river valleys in Dunn, McKenzie, Mercer, and Oliver counties
(Croft, 1973; Klausing, 1979b; Croft, 1985b; Lobmeyer, 1985). East of the
Missouri River, groundwater in the Fox Hills aquifer flows westward (Figure 10)
toward the Missouri River/Lake Oahe (Lake Oahe lies behind Oahe Dam on the
Missouri River and extends from the North Dakota/South Dakota border to just
south of Bismarck).

In Morton County, groundwater flow in the Fox Hills aquifer is primarily
lateral, with little water gained or lost via interaquifer leakage (Ackerman, 1980).
Flow is generally to the east except along the Cannonball River where it
deviates south toward the river. In the southeastern corner of the county, glacial
drift aquifers directly overlie the Fox Hills aquifer. Head differences in these
units indicate a general trend toward upward discharge into the glacial deposits
from the Fox Hills aquifer (Ackerman, 1980).

Groundwater flow in the Fox Hills aquifer in Sioux and Grant counties is
primarily northeasterly except along the Cannonball River, where groundwater
discharges to the river. In areas where the Fox Hills and Hell Creek aquifers are
separated by less than 20 m of bentonitic shale or siltstone, the water levels in
the Hell Creek aquifers are generally about 3 m higher than those in the Fox
Hills aquifer (Randich, 1979). In areas where thicker units separate the aquifers,
the water levels in the Fox Hills aquifer are generally 15 to 30 m below those in
the perched and semiperched Hell Creek aquifers, indicating that the Fox Hills
aquifer probably receives some recharge from the overlying Hell Creek aquifers
(Randich, 1979). However, low annual precipitation (40 cm) and high potential
evaporation (90 cm) results in a low rate of recharge, with most occurring from

March to early June (Howells, 1982).

 

33

In Emmons County, the Fox Hills Formation has been severely eroded
south of Beaver Creek, limiting the aquifer to the Timber Lake Member. North of
Beaver Creek, both the Timber Lake and Colgate members may be present and
yield water to wells if saturated (Armstrong, 1978). Recharge to the Fox Hills
aquifer occurs primarily from infiltration of precipitation and snowmelt.
Groundwater generally flows to low-lying areas and eventually to Lake Oahe.
Discharge also moves laterally into valley deposits (Armstrong, 1978).

Hell Creek Aguifers. In western North Dakota a sandstone unit at the
base of the Hell Creek Formation is in hydraulic connection with the Fox Hills
aquifer forming the Fox Hills-basal Hell Creek aquifer. However, in south-central
North Dakota, 8 to 27 m of siltstone and bentonitic shale separate the
sandstones of the Hell Creek and Fox Hills formations. In this region, sandstone
beds in the Hell Creek Formation are generally discontinuous and not laterally
extensive (Randich, 1979; Ackerman, 1980).

The hydraulic conductivity of core samples from the Hell Creek aquifers in
Grant and Sioux counties average 5.5 x 10(5 m/d (Randich, 1979) and in Morton
County 0.2 m/d (Ackerman, 1980). Transmissivities determined from slug tests
in Sioux and Grant counties range from 1.4 to 7.3 mm with an average of 3.2
mm. Porosities range from 25 to 47 percent in Grant, Sioux, and Morton
counties (Randich, 1979; Ackerman, 1980).

Groundwater movement in the Hell Creek aquifers of Morton County is
generally lateral and to the east (Ackerman, 1980). Discharge occurs in the
valleys of the Heart, Cannonball, and Missouri rivers and as leakage into glacial-
drift aquifers (Ackerman, 1980). In Grant and Sioux counties, groundwater
generally flows toward the northeast except along the outcrop where the flow
mimics the surface topography (Randich, 1979). Water levels in the lower

sandstones are generally within 3 m of the water levels in the Fox Hills aquifer,

 

 

 

34

while stratigraphically higher sandstones may have water levels 15 to 30 m
above those in the Fox Hills aquifer (Randich, 1979). Thick sequences of silty
and clayey material separate the more permeable beds, restricting recharge. In
a climate where potential evaporation greatly exceeds precipitation, perched and
semiperched water tables form, resulting in large differences in water levels of
the adjacent aquifers (Howells, 1982). The Hell Creek Formation is generally
unsaturated in Emmons County (Armstrong, 1978).

Glacial Deposit Aguifers. The most important glacial deposit aquifers in
Sioux, Morton, and Grant counties are associated with buried bedrock valleys.
The principal aquifers in the study area are the Shields Aquifer and the Little
Heart Aquifer (Figure 7).

The Shields Aquifer occupies the southern extent of the Killdeer—Shields
Diversion Channel, which coincides with the Verone ice—margin southwest of the
Missouri River (Randich, 1979; Ackerman, 1980; Bluemle, 1984). The aquifer
consists of several sand and gravel beds, with the most permeable materials
along the central axis of the buried valley and at the valley bottom (Randich,
1979; Ackerman, 1980). Recharge enters the aquifer from hydraulically
connected adjacent aquifers and as infiltration of precipitation. The aquifer
discharges to streams, Lake Oahe, and an adjacent glacial aquifer.

The Little Heart aquifer occupies both a buried-valley system and a
glacial lake basin (Ackerman, 1980). The aquifer material consists of sand and
gravel beds, with the most permeable material along the axis of the valleys and
near the valley bottoms. Recharge enters the aquifer from adjacent aquifers and
as infiltration of precipitation and stream water. The aquifer discharges to small

streams, Lake Oahe, and the Missouri River.

 

 

35

Data Analysis and Interpretation

A finite difference groundwater flow model was used to simulate present
flow conditions in Sioux, Grant, and Morton counties.

Conceptual Physical System. The Fox Hills aquifer is comprised of two
sandstone members that dip northwestvvard toward the center of the Williston
Basin. Along the Missouri and Cannonball river valleys in Sioux, Grant, and
Morton counties the Fox Hills Formation subcrops beneath glacial and alluvial
deposits (Figure 4). Along the Missouri River valley in Emmons County, the
formation is eroded isolating the Fox Hills aquifer in the study area from the
aquifer in Emmons County. The Fox Hills aquifer is confined by the underlying
marine Pierre Formation and overlying siltstone and bentonitic shale units of the
Hell Creek Formation and glacial till.

The conceptual model of the Fox Hills aquifer in the study area is shown
in Figure 11. Essentially horizontal flow is assumed to occur in the aquifer with
possible recharge/discharge occurring along the upper and lower boundaries.
Thus, vertical components of flow are considered negligible. The aquifer is
modelled in two dimensions in the horizontal plane. Prescribed head boundaries
are assigned to all four model boundaries. This allows water to enter and leave
the modelled region by throughflow. Any additional gains or losses to the
system are attributed to recharge or discharge through the upper or lower

boundaries.

Mathematical Statement. The governing partial differential equation for
the conceptual model is
d(T dh/ dx)/ dx + d(T dh/ dy)/ dy + R = 0,
where T is the transmissivity,

h is the head in the aquifer,

 

 

36

Missouri
River
Valley

(sink)

Fox

 

Figure 11. Conceptual model of the Fox Hills aquifer.

37

R is a source/sink term, and

x,y refer to the location in the horizontal plane.

This equation describes horizontal flow in a 2-D, confined, heterogeneous,
isotropic aquifer with a sink/source under steady-state conditions. The
prescribed head boundaries are described as

N: hix.y,,,) = h,,(x.y,_,>,

S: h(x,y,,,) = h...(x.y,.,),

E1 h(X,,,,y) = h,,,,(X,_,,Y),

W: h(X,,,.Y) = h,,,(x,,,,y).
where hm refers to water levels for the specified grid nodes on a contour map of
present water levels in the Fox Hills aquifer.

Parameter Values. Maps of the water-level distribution and the
distribution of transmissivity values were constructed for use in the simulation.

A map of the water levels in the Fox Hills aquifer of Sioux, Grant, and
Morton counties was constructed using published water-level data from 44 wells
(Croft, 1970; Trapp, 1971; Randich, 1975; Ackerman, 1977; Appendix B) and the
contouring computer program SURFER. The kriging method was used to
calculate water-levels for a 26 x 26 grid covering the three county study area.
The resulting map (Figure 12) shows the general flow direction to be toward the
east. Bending equipotential lines along the Cannonball River/Cedar Creek and
Heart River valleys indicate discharge from the Fox Hills aquifer is occurring in
these regions.

Transmissivity values (T=Kb) were estimated using the sandstone
thicknesses (b), determined from 42 drill logs (Chapter 1), and a constant
hydraulic conductivity value (K) Of 0.57 m/d. The 42 calculated transmissivity
values were then contoured with SURF ER using the kriging method for the same

26 x 26 grid as above. The resulting map is shown as Figure 13.

 

 

38

 

0 3 6 12 18miles
h—Q—I.——.,—L,—,—d
0 5 IO I5 20 25kilomclers

Figure 12. Water-level map of the Fox Hills aquifer.

 

 

39

 

Cl=4m2/d

O 8 6 12 IBmiles
)——§—~—,—.¢.—.,_¢
o 5 10l5 20 25kilometers

Figure 13. Transmissivity map of the Fox Hills aquifer.

 

 

40

2—D Finite Difference Model. A 2-D lADl finite difference computer code,
SAM4 (Kinzelbach, 1986), was used for the simulation. This code uses the
iterative alternating implicit procedure which combines equation solving and
iterative procedures. SAM4 requires essentially horizontal flow in the model
aquifer and allows for cell specific recharge and discharge. The Fox Hills
aquifer was modeled as a steady-state (8:0) confined aquifer on a 26 x 22 grid
system (Dx= Dy) that coincides with the lower 22 rows of the water-level and
transmissivity maps presented above (Figure 14). Prescribed head boundaries
were used on all sides of the model area. The upper boundary of the grid
follows an east-west streamline. The water-level grid (map) was used to assign
the prescribed and "initial" heads for each cell; the transmissivity grid (map) to
assign transmissivity values. An iteration error limit of 0.05 m was chosen.
Recharge/discharge was used to calibrate the model to the present water-level
grid map by trial and error.

Simulation Results. The first simulation was run without any recharge or
discharge to the system. Simulated water levels were much higher (20-30 m)
than observed levels, indicating that water is discharged from the Fox Hills
aquifer in the modeled region. The Cannonball and Missouri river valleys, where
the Fox Hills Formation crops out, are considered to be the
major discharge areas for the aquifer (Randich, 1979; Ackerman, 1980).
Attempts to simulate the observed water levels by discharging water along the
Fox Hills Formation subcrop were unsatisfactory, indicating that discharge must
occur over a larger region. Extending the discharge area westward along the
Cannonball River/Cedar Creek valley improved the simulation.

Groundwater flow in the Fox Hills aquifer in Morton County is considered
to be lateral with only small amounts of leakage into or out of the aquifer

(Ackerman, 1980). However, the water-level map indicates that discharge is

 

41

o prescribed head cell
0 discharge cell

         

  

IIIIIIIIIF “IIIIIII
IIIIIIIIIIfi

IIIIIIIMIIIIIIIK}

'J
u

IIIIIII
IIIflIII

I

I

I

I

I

I

I

I

I

E
IIIIIIIIIIIIIflIII
IIIIIIIIIIIIIQIII
IIIIIIIIfiIIIEmIII
IIIIIIIIHIIIIIIII
IIIIIIIIHIIIIIIII-

IIIIIIIIHIIIIIII

  
 

IIHIIIIII
IIflIIIIII
IIHIIIIII
IIflIIIIII
III! IIIII
IIMIMII II
IIHIIIIIIIIIIIIIIIIIIIIIII w

IIBIHEHuuuuuuuuuuuuunuuuufl w

5km O 3 6 I2 IBmiIes
)—§—~——,—.r.,—._r
o 5 IO 15 2O 25kilomelers

EIIIIIIIIIIMIII

IIIIIIIIIIIIIIII
IIIIIIIEIEEEIHIII

IIIIIIIIIIIIII

I
I.
”II

4

a

   
 
   

IIIIIIIIIIIIIIII
IIIIIIIIIIIIIIII
IIIIIIIIIIIIIIII

I
I
I
I
I
I

 

unis
It——<

Figure 14. Finite—difference grid used for simulation of the Fox Hills aquifer.

 

42

occurring along the Heart River valley (Figures 10 and 12). These differences
may be reconciled if the Fox Hills aquifer is in hydraulic connection with Hell
Creek aquifers in the Heart River valley. The Heart River valley is a major
discharge area for the Hell Creek aquifers (Ackerman, 1980). The possibility of
a hydraulic connection between the two aquifer systems is recognized in the
literature (Ackerman, 1980). Modeling discharge along the Heart River valley
improved the overall simulation.

A satisfactory simulation of present water levels in the Fox Hills aquifer
was obtained (Figure 15) when water was discharged from the aquifer at a
constant rate of 0.5 mm/yr along the Cannonball River/Cedar Creek valley, the
Heart River valley, and the Missouri River valley (where the Fox Hills Formation
crops out).

No recharge was introduced to the system. The mean deviation from the
present water levels for the 438 variable head cells was 1.3 m, i.e. the simulated
water levels were 1.3 m higher than the observed values. The standard
deviation (spread around the mean) was 4.9 m.

Interpretation. The Fox Hills aquifer water-level map shows that the
discharge area of Sioux and Morton counties should receive its water from
upgradient in the aquifer via throughflow and that discharge from the aquifer
occurs along the Missouri, Cannonball, and Heart river valleys. Water-levels in
the aquifer were satisfactorily simulated assuming water is discharged at a rate
of 0.5 mm/yr in the 3 major river valleys. The simulation results support the
hypothsis, suggested in the literature, that only minimal recharge enters the
aquifer in the discharge area. Water—levels in the aquifer were simulated with a

mean and standard deviation of 1.3 m and 4.9 m, respectively, without adding

recharge to the system.

 

 

43

 

SD
CIIIOm

0 3 6 12 thiles

0 5 1015 20 25kilometers

Figure 15. Simulated water levels in the Fox Hills aquifer.

 

 

44

The hydrogeologic investigation supports hypothesis (a), i.e., upgradient
aquifer water is a source of water for the discharge area of the Fox Hills aquifer.
Hypothesis (b), i.e., local precipitation is a potential source of water to the
discharge area, is not supported by the steady-state, 2-D simulation. This is
consistent with Howells (1982) assessment that a low rate of recharge results
because of the combination of low annual precipitation and high potential
evaporation. Hypothesis (9), i.e., leakage from adjacent hydrologic units into the
discharge area, is also not supported by the steady-state, 2-D simulation.
Although Randich (1979) observed that in some areas of Morton County the
water levels in the Fox Hills aquifer are generally 15 to 30 m below those in the
Hell Creek aquifers and suggested that the Fox Hills aquifer probably receives
some recharge from the overlying Hell Creek aquifers, Howells (1982) noted that
thick sequences of silty and clayey material separate the more permeable beds
in Sioux and Corson counties, restricting recharge. Thus the simulation results,

i.e., minimal recharge to the system, are consistent with Howells assessment.

Summary

The Fox Hills aquifer is recharged along the Cedar Creek anticline in
southeastern Montana and southwestern North Dakota where the aquifer crops
out, and by leakage from overlying aquifers in southwestern North Dakota.
Groundwater flow is generally to the east and northeast with the main discharge
area along the Missouri and Cannonball rivers in Sioux and Morton counties.
East of the Missouri River, groundwater in the Fox Hills aquifer flows westward
toward the Missouri River/Lake Oahe. Low annual precipitation and high

potential evaporation results in a low rate of recharge, with most occurring from

March to early June.

 

 

 

45

A 2-dimensional finite difference groundwater flow model was used to
simulate present flow conditions in Sioux, Grant, and Morton counties. Maps of
the water-level distribution and the distribution of transmissivity values were
constructed for use in the simulation. The water-level map shows the general
flow direction to be toward the east. Bending equipotential lines along the
Cannonball River/Cedar Creek and Heart River valleys indicate discharge from
the Fox Hills aquifer is occurring in these regions. A satisfactory simulation of
present water levels in the Fox Hills aquifer was obtained using Kinzelbach's
(1986) 2-D IADI finite difference model when water was discharged from the
aquifer at a constant rate of 0.5 mm/yr along the Cannonball River/Cedar Creek
valley, the Heart River valley, and the Missouri River valley (where the Fox Hills
Formation crops out). The mean deviation from the present water levels for the
438 variable head cells was 1.3 m. The standard deviation (the spread around
the mean) was 4.9 m. The simulation results suggest that only minimal recharge
enters the aquifer in the discharge area.

The hydrogeologic investigation supports hypothesis (a), that upgradient
water is the source of water in the discharge area of the Fox Hills aquifer in
Sioux, Grant, and Morton counties. Hypotheses (b) and (e), local
precipitation/recharge and leakage from adjacent aquifers, are not supported by
the hydrogeologic investigation. These results are consistent with Howells
(1982) assessment that a low rate of recharge results because of the
combination of low annual precipitation and high potential evaporation and that

thick sequences of silty and clayey material separate the more permeable beds,

restricting recharge.

 

CHAPTER 3: HYDROGEOCHEMISTRY

Literature Review

Previous studies of the water chemistry of the Fox Hills aquifer will be
reviewed, followed by a discussion of the water chemistry of the Dakota aquifer.

Fox Hills Aguifer. Several studies have been conducted on the water
chemistry of the Fox Hills aquifer (Groenewold et al., 1979; Thorstenson et al.,
1979). Thorstenson et al. examined the hydrochemistry of the Fox Hills aquifer
in southwestern North Dakota and northwestern South Dakota. They found that
the water chemistry changes significantly downgradient in the aquifer. For
example, in the recharge area, the water contains primarily sodium, bicarbonate,
and sulfate ions and traces of H28 and CH4. Downgradient, the water chemistry
changes to contain primarily sodium, bicarbonate, and chloride ions, and more
CH4 is present. They also found that helium concentrations in the discharge
area increased several orders of magnitude above atmospheric saturation
levels. Thorstenson et al. concluded that most of the chemistry changes
described above could be explained reasonably by processes occurring within
the aquifer (i.e., sulfate reduction in the presence of lignite resulting in pyrite
formation) and Ca-MglNa exchange. The authors attributed the downgradient
increases in chloride and helium to leakage from the Pierre Formation or
underlying formations. Using available hydrodynamic data, they estimated that
the water in the aquifer was moving at a rate of 0.85 m/yr with the water in the
discharge area approximately 250 ka.

Groenewold et al. (1979) studied the hydrochemistry of the Fox Hills
aquifer in southwestern North Dakota and also concluded that sulfate reduction

in the presence of lignite and Ca—MglNa exchange were responsible for the

46

 

 

47

downgradient change In water chemistry. However, they noted that lignite is
rare in the aquifer, limiting the reaction. They suggest that sulfate reduction in
the aquifer may be controlled by the rate of diffusion into the aquifer of dissolved
organic matter from the overlying confining layer or by the rate of sulfate
diffusing out of the aquifer into the sulfate—deficient confining layer. Groenewold
et al. attributed the downgradient increases in chloride concentration to diffusion
from the Pierre Formation. In addition to studying the geochemistry,
Groenewold et al. determined 14C ages for waters from 6 locations, which
ranged from <10 ka to 27 ka. The oldest ages were determined for wells in
Dunn County (Figure 10), which they interpreted as indicating that the water in
the Fox Hills aquifer west of the Missouri River is generally younger than 30 ka
(however, Dunn County is bisected by a N-S groundwater divide, and it is likely
that downward leakage of relatively recent water may have occurred in this
area). They concluded that since no glacial advances have extended west of
the Missouri River in the last 30 ka, the effects of glaciation on the chemical
evolution of water presently in the Fox Hills aquifer would be minimal. They also
analyzed two samples for 5'80 from wells in Dunn County that produced values
of -17 and -17.4, but provided no explanation for the light values.

Chlorine-36/Cl ratios for seven water samples from the Fox Hills aquifer in
southwestern North Dakota have been reported by Davis and Bentley (1982)
and Bentley et al. (1986). Since the ratios tend to decrease rapidly along the
flow path from 258 x 10'15 to 7 x 10'15 as chloride concentrations increase,
Bentley et al. (1986) have suggested that upward leakage from the Dakota
aquifer (Newcastle Formation) may be replacing the water in the Fox Hills
aquifer.

Dakota Aguifer. The upper part of the Dakota aquifer (Newcastle

Formation) in North Dakota yields sodium chloride type water with chloride

 

48

concentrations in the range of 5,000 mglL (Howells, 1982; Peter, 1984). The
lower part of the Dakota aquifer (lnyan Kara) in south-central North Dakota
yields saline to very saline water. Howells (1982) observed a pronounced
chemistry change in Corson County, SD (directly south of Sioux County). He
noted that near the Missouri River, the aquifer yielded sodium-calcium-
magnesium-chloride-sulfate type water with a total dissolved solids (TDS)
content of 2,500 mglL. Ten miles west of the river, the TDS content is greater
than 5,000 mglL and the water is of the sodium—chloride type. Twenty miles west
of the river, the TDS content is greater than 10,000 mg/L. In Emmons County,
east of the Missouri River, the lower part of the Dakota aquifer yields sodium—

sulfate type water (Armstrong, 1978).

Data Analysis and Interpretation

Graphical Analysis. Major ion chemistry data were obtained for 248 wells
in the Fox Hills aquifer of southwestern North Dakota from published county
reports (Croft, 1970; Trapp, 1971; Croft, 1974; Randich, 1975; Ackerman, 1977;
Klausing, 1979a; Anna, 1980; Croft, 1985a). The data were converted to
percent equivalents per million (% epm) and plotted on a Piper trilinear diagram
(Zaporczec, 1972; Figure 16; Appendix C).

Sodium is the dominant cation throughout the aquifer comprising over
90% epm of the cations in 236 of the 248 samples. Two samples having <90%
epm sodium were from wells in western Bowman County, where the Fox Hills
Formation crops out in the recharge area. Ten additional samples with <90%
epm sodium were from wells in Sioux, Morton, and Grant counties, at or near the

formation subcrop in the discharge area.

 

 

 

 

49

100

      
 

60 40

Ca Zone2

Figure 16. Piper diagram of Fox Hills aquifer water in
southwestern North Dakota.

 

 

50

The anion chemistry data were more variable. When plotted, the data fell
within four distinct zones on the Piper anion triangle (Figure 16). The majority of
the samples (52%) fell in zone lll, representing bicarbonate-chloride and
chloride-bicarbonate chemistries (>90% epm). The next largest group of
samples (38%) fell in zone I, representing bicarbonate-sulfate and sulfate-
bicarbonate chemistries (>90% epm). Only 6% of the samples fell in zone IV
(bicarbonate-sulfate-chloride) and 4% in zone II (bicarbonate, >90% epm).

Hydrochemical Facies. The distribution of anion facies in southwestern
North Dakota is shown in Figure 17. Zone I type waters occur along the
recharge area west of the Little Missouri River valley and within the Little
Missouri River valley discharge area. Zone I type waters also occur along the
Missouri River discharge area in Sioux, Morton, and Grant Counties, primarily
where the Fox Hills Formation crops out. Zone III type waters dominate the
remainder of the area with zone IV type waters fringing the zone l-zone Ill
contact. Zone ll type waters occur locally and may represent areas of significant
downward leakage from overlying aquifers.

Recharge to the Fox Hills aquifer in southwest North Dakota occurs as
leakage from the overlying Hell Creek-lower Ludlow aquifer. The Hell Creek
Formation contains beds Of lignite which serve as an energy source for sulfate-
reducing bacteria (Anna, 1981 ). Sulfate reduction in the Fox Hills aquifer may be
controlled by the rate of diffusion of dissolved organic matter from the overlying
confining layer (Groenewold et al. 1979). Consequently, sulfate concentrations
in the Fox Hills aquifer decrease in the downgradient direction. Paralleling the
sulfate decrease is an increase in chloride concentrations, possibly due to
diffusion from the Pierre Formation (as discussed below). The result of these
processes is a shift from a sodium-bicarbonate-sulfate type water (zone I) to a

sodium—bicarbonate-chloride type water (zone III) in the downgradient direction.

 

 

EXPLANATION

e 360: data '

200“

CI:

51

  
      

 

  

EMMONS

 

 

52

Sodium-bicarbonate-sulfate type water in the Fox Hills aquifer in Sioux,
Morton, and Grant counties is a water chemistry anomaly because upgradient
waters are of the sodium-bicarbonate—chloride type. Since sulfate reduction is
an irreversible process and precipitation of chloride minerals is unlikely in the
Fox Hills aquifer, the data indicate that this water is derived from a source other
than the upgradient water. Groenewold et al. (1979) attribute the sodium-
bicarbonate-sulfate type water in south—central North Dakota to a recharge area
in north-central South Dakota; however, the areal extent of zone I type waters
exceeds the influence of this local groundwater high. Bentley et al. (1986) have
suggested that upward leakage from the Dakota aquifer may be replacing the
water in the Fox Hills aquifer. This hypothesis does not hold for the anomalous
water in Sioux, Morton, and Grant counties because the Dakota aquifer yields
sodium-chloride type water in south-central North Dakota west of the Missouri
River. The shape of the sodium-bicarbonate-sulfate type anomaly is similar to
that of the Fox Hills Formation subcrop, suggesting that the freshwater entered
the Fox Hills aquifer along the formation subcrop.

Chloride Distribution. Chloride concentrations in the Fox Hills aquifer
generally increase from the recharge area along the Cedar Creek Anticline
toward the Missouri River discharge area. Formations overlying the Fox Hills
aquifer are generally of non-marine origin, and any chloride minerals formed
during the deposition of the Fox Hills Formation (littoral) should be flushed out of
the aquifer (Thorstenson et al., 1979). Thus, the marine Pierre Formation or
underlying formations are the logical source of chloride. Thorstenson et al.
(1979) and Groenewold et al. (1979) both suggest that the chloride
concentration increases in the Fox Hills aquifer are due to input from the Pierre
Formation, while Bentley et al. (1986) suggest that Dakota aquifer water is

leaking into and replacing the Fox Hills aquifer water. In southwestern North

 

 

53

Dakota, the hydraulic head in the Dakota aquifer is generally lower than that in
the Fox Hills aquifer. Thus, upward leakage from the Dakota aquifer does not
occur throughout most of the region and the increase in chloride concentrations
in the Fox Hills aquifer cannot be attributed to leakage from the Dakota aquifer.
The observed chloride concentrations in the main body of the Fox Hills aquifer
are best explained as input from the Pierre Formation.

Figure 18 is a map of the Fox Hills aquifer chloride distribution in south-
central North Dakota. A low—chloride (<1 meq/L) zone occurs just west of the
Missouri River, principally in the Fox Hills Formation subcrop/outcrop area. This
low-chloride zone coincides with the sodium-bicarbonate—sulfate type water
anomaly identified in Sioux, Grant, and Morton counties. The chloride
concentrations can therefore be used to estimate the relative volume of
freshwater input to the discharge area. To dilute the upgradient water (>9 meq/L
CI) to <1 meq/L Cl would require approximately 9 parts freshwater to 1 part
upgradient water. In the southeastern corner Of Grant County, the chloride
concentrations drop from >6 meq/L to < 1 meq/L in a 6 km stretch along the
groundwater flow path. In order to bring about this decrease in chloride
concentration (by mixing with fresh water), a 500% increase in the volume of
water would be required as the water moves downgradient through this region.
Such an increase in the water volume would require recharge on the order of 4.3
to 8.5 mm/yr, only in the narrow band with chloride concentrations in the range
of 1 to 6 meq/L. Neither the literature or water-level maps of the aquifer suggest
any unusual conditions that are restricted to this region. It is unlikely that local
recharge under present climatic conditions could explain this increase in water
volume. A climatic regime capable of providing large volumes of recharge to the

discharge area, as opposed to a narrow band in the discharge area, occurred

 

 

54

EXPLANATION
A sample location

chloride concentration

CORSON

 

0 3 6 t2 18miles
H—q—dg—q—l
0 5 to 15 20 25kllomelers

Figure 18. Chloride distribution in the Fox Hills aquifer.

 

 

55

during the Pleistocene when ice sheets advanced west of the Missouri River
valley (Chapter 5).

Chloride concentrations are relatively constant in the low-chloride zone
suggesting a near constant residence time for the water as chloride
concentration would normally increase with age due to diffusion from the Pierre
Formation. A rapid recharge event would be necessary to explain the observed
narrow range of concentrations in the low-chloride zone. Recharge induced by
an overriding ice sheet during the Pleistocene could account for the Observed
chloride distribution.

Average Linear Velocity from 36Cl. Chloride generally lacks sources and

sinks in shallow groundwater systems due to its high solubility and minimal
geochemical interaction. This, along with a half-life of 3.01 x 105 a, makes 36Cl
ideally suited for dating old (50 ka to 1 Ma) ground water (Bentley et al., 1986).
To calculate the age of ground water using 36Cl, the initial 36Cl concentration of
the water and the secular equilibrium 36CI/Cl ratio for the aquifer must be known.
The secular equilibrium ratio may be determined from field data, provided
secular equilibrium has been reached in a distal portion of the aquifer or the
secular equilibrium ratio may be calculated using chemical and hydrologic data.
Bentley et al. (1986) calculated a typical ratio for ground water in a sandstone
aquifer of 4.7 x 10'”. The initial 36Cl/CI ratio may be estimated using field data
from the recharge area or from a published map for the United States. If
chloride concentrations increase along the flow path, the additional source of
chloride must be accounted for in the calculation of the 36Cl age. For the case of
cross-aquifer leakage or diffusion of salt from aquitards, the following equation is
employed (Bentley et al., 1986):

= — t" In [c 0,;1 (R - R...) (R0 - Rser‘j
where I» is the 36Cl decay constant (2.3 x 10‘6 a“)

 

 

 

56

C is the measured chloride concentration
Co is the initial chloride concentration

R is the measured 36Cl ratio

R0 is the initial ratio, and

R5,. is the secular equilibrium ratio.

The travel time from the recharge area to the Missouri River discharge
area was estimated using published 3‘SCl/Cl ratios for the Fox Hills aquifer (Davis
and Bentley, 1982), the associated chloride concentrations (Croft, 1974;
Ackerman, 1977), and a secular equilibrium ratio of 4.7 x 10'15. Two wells
approximately 206 km apart and along a flow line (Figure 17) have ratios of 258
x 10‘15 and 10.2 x 10'15 and concentrations of 36 and 560 mg/L, respectively.
The calculated travel time is 450k years, yielding an average linear velocity of
0.43 m/yr. This velocity is close to Thorstenson et al.'s (1979) estimate Of 0.85
m/yr. Groenewold et al. (1979) report an age of 15 to 20 ka for the upgradient

well based on 1“C. Thus, the age of the water at the downgradient well is about

465 ka.

Summary

Groenewold et al. (1979) and Thorstenson et al. (1979) studied the
hydrochemistry of the Fox Hills aquifer in southwestern North Dakota and
observed that water in the recharge area contains primarily sodium, bicarbonate,
and sulfate ions, while downgradient water contains primarily sodium,
bicarbonate, and chloride ions. They concluded that sulfate reduction in the
presence of lignite and Ca-Mg/Na exchange were occurring in the aquifer. The
authors attributed the downgradient increases in chloride to leakage from the

Pierre Formation or underlying formations. Bentley et al. (1986) have suggested

57

that the increase in chloride concentrations is due to upward leakage from the
Dakota aquifer (Newcastle Formation), which may be replacing the water in the
Fox Hills aquifer.

Major ion chemistry data were obtained for 248 wells in the Fox Hills
aquifer of southwestern North Dakota from published county reports. Sodium is
the dominant cation throughout the aquifer comprising over 90% epm of the
cations in 236 of the 248 samples. The anion chemistry data were more
variable. Bicarbonate-sulfate and sulfate-bicarbonate (>90% epm) type waters
occur in the recharge area along the North Dakota-Montana border and in the
discharge area west of the Missouri River in Sioux, Morton, and Grant Counties
(primarily where the Fox Hills Formation crops out). Bicarbonate-chloride and
chloride-bicarbonate (>90% epm) type waters dominate the remainder of the
area. Sulfate reduction and chloride diffusion explain the shift from a sodium—
bicarbonate—sulfate type water to a sodium-bicarbonate-chloride type water in
the downgradient direction. However, sodium-bicarbonate-sulfate type water in
the Fox Hills aquifer in Sioux, Morton, and Grant counties is a water chemistry
anomaly suggesting that freshwater recharged the aquifer in it the discharge
area. Leakage from the underlying Dakota aquifer cannot explain the
anomalous water chemistry in the Fox Hills aquifer because the Dakota aquifer
yields sodium-chloride type water in south—central North Dakota west of the
Missouri River. The shape of the sodium-bicarbonate-sulfate type anomaly is
similar to that of the Fox Hills Formation subcrop, suggesting that the freshwater
entered the Fox Hills aquifer along the formation subcrop.

A low-chloride (<1 meq/L) zone occurs just west of the Missouri River,
principally in the Fox Hills Formation subcrop/outcrop area. This low-chloride
zone coincides with the sodium-bicarbonate-sulfate type water anomaly

identified in Sioux, Grant, and Morton counties. To dilute the upgradient water

 

 

58

(>9 meq/L CI) to <1 meqlL Cl would require approximately 9 parts freshwater to
1 part upgradient water. In the southeastern corner of Grant County, where the
chloride concentrations drop from >6 meq/L to < 1 meq/L in a 6 km stretch along
the groundwater flow path, a 500% increase in the volume of water would be
required as the water moves downgradient through this region. Such an
Increase in the water volume would require recharge on the order of 4.3 to 8.5
mm/yr, only in the narrow band with chloride concentrations in the range of 1 to
6 meqlL. Neither the literature or water-level maps of the aquifer suggest any
unusual conditions that are restricted to this region. It is unlikely that local
recharge under present climatic conditions could explain this increase in water
volume.

Chloride concentrations are relatively constant in the low—chloride zone
suggesting a near constant residence time for the water as chloride
concentration would normally increase with age due to diffusion from the Pierre
Formation. A rapid recharge event would be necessary to explain the observed
narrow range of concentrations in the low-chloride zone.

The travel time from the recharge area to the Missouri River discharge
area was estimated using published 36Cl/Cl ratios for the Fox Hills aquifer, the
associated chloride, and a secular equilibrium ratio of 4.7 x 1045. The calculated
travel time is 450k years, yielding an average linear velocity Of 0.43 m/yr.

The hydrogeochemical investigation does not support hypothesis (a), that
upgradient aquifer water is a significant source of the water in the discharge
area of the Fox Hills aquifer in Sioux, Grant, and Morton counties. In addition,
hypotheses (b) and (e), local precipitation/recharge and leakage from adjacent
aquifers, are not supported by the hydrochemical investigation and this is

consistent with the results of the hydrogeological investigation (Chapter 2).

 

 

CHAPTER 4: STABLE ISOTOPE HYDROLOGY

Literature Review

Stable isotopes of hydrogen and oxygen are useful tracers in
hydrogeological investigations. Incorporated into the water molecules
themselves, the stable isotopes, deuterium (D) and oxygen-18 (‘80), are
generally considered conservative in low-temperature environments (IAEA,
1983).

Isotopic concentrations of water samples are compared to an
internationally agreed upon standard, Standard Mean Ocean Water (SMOW),
and expressed as the deviations (d per mil) from SMOW (IAEA, 1983):

5 per mil = (Reample/RSMOW ‘ 1) 103
where R is the ratio of the rare to common isotope. Positive 6 values indicate
excess with respect to the standard; negative values, depletion.

Atmospheric Waters. Craig (1961) found that the 6180 and OD values in
precipitation and fresh waters generally plot along a straight line (SD = 8 8180 +
10). This line is referred to as the global meteoric waterline. The International
Atomic Energy Agency (IAEA), in association with the World Meteorological
Organization, established a worldwide network of 144 stations to survey
hydrogen and oxygen isotope concentrations in precipitation. The relationship
between 6180 and 8D for these stations (SD = (8.08 :I: 0.8) 6130 + (9.57 :t 0.62)) is
similar to the global meteoric water line of Craig (1961; Yurtsever and Gat,
1981). The isotope composition for continental stations in North America is
described by the relationship (Yurtsever and Gat, 1981):

SD = (7.95 i 0.22) 8180 + (6.03 i 3.08).

59

 

 

60

A recent study by the North Dakota State Water Commission determined the
following local meteoric water line for Oakes, North Dakota (approximately 200
km east of the study area) based on 19 precipitation samples collected from
April 2, 1989 to April 16, 1990 (Shaver, personal communication):

SD = (7.83 i 0.38) 8180 + (6.99 :t 5.53).
This local meteoric water line for North Dakota is similar to the North America
continental meteoric water line.

Dansgaard (1964) related the degree of depletion to geographic and
climatological parameters such as latitude, altitude, distance from the coast, the
amount of precipitation, and temperature. Temperature was found to be the
major parameter determining the isotopic composition of precipitation, which is
expressed by the following empirical equations (Dansgaard, 1964):

6180 = 0.695 Ta — 13.6 per mil, and

SD = 5.6 T3 - 100 per mil,

where T,1 is the local mean annual air temperature.
Dansgaard's (1964) conclusion was supported by a subsequent study (Yurtsever
and Get, 1981) that was conducted on a larger sample data base and employed
multiple linear regression techniques. Yurtsever and Gat show that the mean
isotopic composition of precipitation is described primarily by average monthly
temperature. Correlation to other geographical parameters was found to be not
significant. Although Yurtsever and Gat assert that these findings reflect the
situation on a global scale, these authors also indicate that the amount effect or
evaporation effect may be important factors on a regional scale (Yurtsever and
Get, 1981).

Lake Waters. Lakes, as well as other surface waters, are subject to
evaporation even with short exposure time. This evaporation results in an

enrichment of the isotope content of the water body (Fontes, 1980) and a

 

 

61

diversion of the data from the meteoric water line. The 8180-8D relationship for
evaporating water bodies is linear with a slope less than 8, generally 2 to 5
(Fontes, 1980). Hwang (1982) collected surface water samples from 14 sloughs
in Oliver County, North Dakota (approximately 75 km north of the study area)
during the period from 1978 to 1980. The 8180-8D relationship for these
samples is:

SD = 5.55 8180 - 26.45,
clearly showing that evaporation is affecting the stable isotope composition of
the slough waters.

Ice and Snow. The d-values of local snow and rain falling on an ice sheet
reflect the local temperature and altitude effect. Snowmelt and rain, with
relatively high d—values, percolating through lighter snow and ice causes a
homogenization of the D and 180 contents for long residence times, with a
general increase in the d-value of the solid phase (Moser and Stichler, 1980;
Arnason, 1981). Oxygen—isotope profiles of deep ice cores from polar ice sheets
can provide information on paleoclimates. Dansgaard and Tauber (1969)
estimated the mean 8‘50 content of the Laurentide ice sheet to be —30 per mil
based on the location of the ice sheet divide, altitude effect, and a cooler
climate. Neglecting isotopic enrichment, the expected 6‘30 content of subglacial
meltwater would be about -30 per mil.

Ground Water. The stable isotope content of ground water is generally
expected to reflect the average local climatic condition of the aquifer's recharge
area (Fontes, 1981). Preferential seasonal recharge gives more relative weight
to recharge waters of cold or humid periods. This has been observed for the
Oakes aquifer (Shaver, personal communication) of North Dakota
(approximately 200 km east of the study area), where the average 6180 value of

29 water samples (-12.9) is similar to the weighted mean precipitation for

 

 

62

November through mid-June (-12.7). Snowmelt and spring rain are assumed to
be the source of recharge to the Oakes aquifer (Shaver, personal
communication). High evaporation rates in an aquifer’s recharge area also
affect the isotopic composition of groundwater. The New Rockford aquifer,
Wells County, North Dakota exhibits a {SD-6180 relationship of

6D = 6.1 8180 - 24.5,
based on 26 groundwater samples (Patch and Knell, 1988) indicating that
evaporation of precipitation/surface water occured prior to recharge.

The climate dependence of the isotopic composition of groundwater
results in a relatively constant stable isotope content within an aquifer.
Variations within an aquifer may occur due to isotope exchange with the aquifer
matrix, mixing of waters of different origins, and large climatic changes (Gat,
1981). Water and aquifer materials are generally in isotopic disequilibrium.
Isotope exchange moves the system toward equilibrium. Only oxygen isotopes
are affected by this process, since the hydrogen content of geologic materials is
generally too low to induce significant isotope exchange (Panichi and
Gonfiantini, 1981). The extent of oxygen isotope exchange depends on (1) the
relative proportions of oxygen in the water aquifer matrix, (2) the initial 180
contents, (3) the specific water—mineral fractionation factors, and (4) the time and
surface of contact. This exchange process usually is negligible at normal
temperatures due to the temperature dependence of water-mineral fractionation
factors (Panichi and Gonfiantini, 1981).

Paleowaters. Atmospheric waters precipitated in the past, generally over
10,000 years ago, are referred to as paleowaters. Paleowaters, such as
Pleistocene waters associated with glacial events, often originated in a different

climatic regime. These climate changes are recorded in the stable isotope

 

 

63

composition of the ground water. Paleoclimate signatures may be assigned
based on differences in 8180 and 8D, deuterium excess, or both (Fontes, 1980).

Deuterium excess is defined by Dansgaard (1964) as

d a 8D - 8 8180.

Merlivat and Jouzel (1979) determined that the deuterium excess, or d-excess, is
primarily a function of the initial relative humidity (h) over the area of vapor
production. They calculated d-excess values of ocean-derived vapor for various
relative humidities, e.g., for h = 0.8, d = 10.7, and for h = 0.9, d = 5.4. A
continuous d-excess profile obtained from an East Antarctic ice core shows d-
excess values 4.5 per mil lower for the coldest part of the last ice age (circa 18
ka) than for the past 7.5 ka (Jouzel et al., 1982). This shift in d~excess is
attributed to a change in relative humidity over the source area for Antarctic
precipitation (Jouzel et al., 1982). Jouzel et al. (1982) also observed an

apparent time-lag of 2,500 yr for 180 following the decrease in d~excess.

Data Collection

Eleven water samples were collected from North Dakota State Water
Commission (NDSWC) wells in Sioux, Grant, and Morton counties for 1‘30 and D
analyses (Figure 19). The samples were collected from the screened interval
without prior purging. Robin and Gilham (1987) have suggested that depth-
discrete sampling without prior purging may, in some cases, be preferrable.
They found that a continual flow of ground water through the screened interval
can be maintained indicating that water in the screened interval would be
representative of the natural ground water. Kearl et al. (1992) observed
horizontal laminar flow in the screened interval in the same direction as local

groundwater flow using a borescope, supporting Robin and Gilham's results and

 

 

 

0 3 6 l2 leiles
W
0 5 IO 15 20 25kilomelers

Figure 19. Location of stable isotope water samples.

 

 

65

indicating that water in the overlying casing does not mix with the water in the
screen. Kearl et al. conclude that diffusion of gases into or out of the ground
water is the only mechanism that could influence water chemistry in the
screened interval. The thickness of the diffusive boundary layer is calculated
using (Kearl et al., 1992):
8 ~ 2(DABt)‘/=
where 6 is the diffusive boundary layer
DAB is the binary diffusivity coefficient of
gas A in solute B; 1045 cm2/sec, and
t is time, taken as the diameter of the borehole
divided by the groundwater flow velocity.
The maximum thickness of the diffusive boundary layer for a 3.175 cm well with
a wellbore flow velocity of 0.43 m/yr (average linear velocity for the Fox Hills
aquifer) is 9.65 cm. The well screens in the NDSWC wells are generally 2 to 7.4
m long, allowing samples to be taken well below the bottom of the casing; that is,
in fresh formation water and, therefore, without fear of drawing stagnant water
into the sampler. No artificial filter packs have been used in these monitoring

wells that might influence the chemistry of the water in the screened interval.

Data Analysis and Interpretation

The water samples were analyzed at the Environmental Isotope
Laboratory, University of Waterloo. The data are plotted on a 5180—6D graph
(see Figure 20) and a best-fit line was determined with slope 8.58 and intercept
15.2 (correlation coefficient = 0.9158). The slope and intercept are considerably

greater than the values estimated for meteoric waters in North America

66

—60

-65 del D = 8.58 del 0-18 + 15.20

correlation coeff. = 0.957
-70 goodness of fit = 0.916

—75
-80
—85
-90
-95
—100
—105
-110
—115

‘120 n=11

F-test: 98
— 5
12 mgnMCantat25%leva
—130

—18 -16 —14 —12 -10

del 0—18

del

 

Figure 20. 60-8180 relationship of the Fox Hills aquifer water samples.

 

 

67

(7.95:t0.22 and 6.03zt3.08, respectively) and at Oakes, North Dakota (7.831038
and 6991553, respectively). A plot of d-excess versus 5‘°o (Figure 21) shows
that the samples fall within three distinct groupings defined by d—excess values
of approximately 4, 7.5, and 10. However, the 8‘80 values show no correlation
with d-excess. This suggests that three paleowaters are present in the study
area that were precipitated under similar climatic conditions. Replotting the data
on 8180-60 graphs according to the d-excess groupings (Figure 22) produces
slopes between 7.92 and 8.06 and intercepts between 4.91 and 9.57, with
correlation coefficients of 0.9977 to 0.9998 (significant at the 2.5% level, based
on F-tests). These values are consistent with both the North American meteoric
waterline and the local (Oakes, North Dakota) meteoric waterline. The slopes
indicate that the ground waters are of meteoric origin and unaffected by
fractionating processes. Thus, evaporation prior to recharge (e.g. proglacial
lakes) is not indicated by the stable isotope data.

Plotting d-excess values on a map of the chloride distribution (Figure 23)
shows that all but one of the samples with d—excess values in the 7.5 and 10
groupings fall within the low-chloride zone identified in Chapter 3. All but one of
the samples outside the low—chloride zone have d-excess values around 4. This
suggests that two different paleowaters are present in the discharge area-~a
low-chloride, high d-excess water and a high-chloride, low d-excess water. The
t test was used to test whether the means of the two waters are the same
(Davis, 1986). The results (t=1.88 with 9 degrees of freedom) indicate that the
two waters are different at the 10% significance level (a=0.10). Equality of
variances, a requirement for the t test, was confirmed by the F test (1.31 for 4/5
degrees of freedom). One sample in the high chloride zone along the Missouri

River has a d-excess value of 10.1; one sample in the low chloride zone has a d-

 

 

 

68

—1O

—11

—12

—13

—14

0-18

-15

dd

—16
~17
—18
—19

—20
O 1 2 3 4 5 6 7 8 9 1O 11 12

D—excess

Figure 21. Deuterium excess-6‘80 relationship of the Fox Hills
aquifer water samples.

 

 

69

d—oxcoss = 4
n=5

F-test: 655

significant at 2.5% level

del D = 8.06 del 0—18 + 4.91
correlation coeff. = 0.9977
goodness of fit = 0.9954

d-excess — 7.5
n=3

F-test: 3167
significant at 2.5% level

del D = 7.92 del 0-18 + 6.41
correlation coeff. = 0.9977

goodness of fit = 0.9954

d—excess = 10
n=3

F-test: 2219

significant at 2.5% level

del D = 7.96 del 0-18 + 9.57
correlation coeff. = 0.9998
goodness of fit = 0.9996

 

—18 —15 -14 —12 -10
del 0—18

Figure 22. (SD—8‘80 relationship by d-excess groupings.

 

 

 

70

 

0 3 6 12 18miles
p—fi—y—q—H—q—i
O 5 1015 20 25kilometers

Figure 23. Deuterium-excess values plotted with the chloride distribution.

 

 

71

excess value of 4. As noted above, the d—excess values for the water in the low-
chloride zone fall into two grouping, one around 7.5 and the other around 10.
One could speculate that this suggests that more than one recharge event
provided the low-chloride water in the discharge area, although at this time there
is insufficient data to test the hypothesis.

The expected values of 8180 and SD for precipitation in Sioux and Morton
counties were calculated using mean annual temperature and Dansgaard's
(1964) temperature equations. For a mean annual temperature of 62°C (Fort
Yates, Sioux County), 8180 and SD would be -9.3 and -65.3 per mil, respectively.
These values are consistent with the stable isotope distribution map for North
America (Drever, 1982).

The groundwater samples collected from the Fox Hills aquifer are
considerably lighter than modern precipitation, indicating that recharge occurred
under cooler climatic conditions. However, the samples are not as light as
would be expected for glacial ice. Mean annual temperature of each sample
was calculated using Dansgaard's (1964) temperature equation and the
respective 6‘80 values (see Table 1). The sample temperatures were 6.9 to
99°C cooler (-16.1 to -14.1 6180) than modern precipitation (-9.3 8180) for all but
one sample, which yielded a temperature 4°C cooler (-12.3 8180) than modern.
It was collected at a location where the Fox Hills subcrops below a glacial valley
aquifer that receives its recharge via infiltration and Hell Creek aquifer
discharge. Water levels in the Fox Hills and the glacial aquifer are
within a meter of each other. Two explanations for this isotopic value are
offered: mixing of aquifer waters and preferential seasonal recharge.

First, waters may be mixing between the Fox Hills and glacial aquifers.
To test the mixing hypothesis, the isotopic composition for modern precipitation

was plotted on a 8180—50 graph along with the Fox Hills aquifer values (Figure

 

 

72
Table 1. Stable isotope data from the discharge area of the Fox Hills aquifer.

m
-mm11mlm-I-l_l
-_
-146 I-1089 -14I

~15 34
-15 08 _i—:_Ilml
.

133N 083W 12ADA1 -12. 28

133N 085W

134N 082W 36000 -15.4

 

 

 

 

135N1083W 32CBB1 -15.69 .

136N 079W 05CCC 44.09 -102.6
136N 081W 07DDC1 -15.43 ' -115.9
138N 081W 09ABB1 —15.02 -116.8

 

 

 

 

l __l __.i
Recorted del 018 and del D values maybe averaoe of 2 relicates

Raw data is in Ao oendix D 1* 1 l
Temerature determined from: Tem = 13.6 - del O-18 [0.695
delta Temperature determined from: delta Temp = 6.2 - Temp l
Deuterium excess determined from: D-excess = del D ~ 8 del O-18

 

 

 

 

 

73

24). The resulting best—fit line could represent a mixing line, supporting the
conjecture that light water in the Fox Hills aquifer may have been mixed with
heavier glacial aquifer water.

A second explanation for the -12.3 (8180) sample is that the Fox Hills
aquifer is receiving seasonal recharge (late winter through spring) via the glacial
aquifer. The 6180 value of -12.3 is similar to that observed for the Oakes
(glacial) aquifer (-12.9), which receives seasonal recharge (Shaver, personal
communication). Assuming the —12.3 8180 to be modern recharge, the Fox Hills
aquifer water samples exhibit temperatures 2.6 to 56°C cooler than modern.

A global circulation model and energy balance model have been used to
simulate temperature changes over the past 18,000 years (Hyde et al., 1989).
These models suggest that the mean annual temperature at 43°N latitude was
about 4 to 7.5°C cooler than modern during the last glacial maximum 18,000
years ago. Earlier glacial advances may have occurred under similar
climatic conditions. Thus the Fox Hills aquifer water isotopic composition may
represent recharge during the Pleistocene when ice sheets advanced into the
aquifer's discharge area.

The meltwater from Pleistocene subglacial ice would be expected to have
8180 values of around -30 per mil, as stated above. The observed 5'50 values
are considerably heavier than this. The average 8180 value for the samples,
excluding the sample that may represent modern preferential recharge, is -15.1.
Mixing of two waters with end points of -12.3, for local precipitation recharge,
and -30, for subglacial ice meltwater, would produce a water with 8180 = —15.1 for
an 84% and 16% contribution, respectively. If the 6180 value of the local
precipitation recharge was lower than -12.3 during the Pleistocene, an even

smaller contribution would come from subglacial meltwater.

 

 

 

74

del D = 8.22 del 0-18 + 10.78
correlation coeff. = 0.9998
goodness of fit = 0.9995

n=4
F-test: 4140
significant at 2.5% level

 

—18 —17 —16 —15 —14 —13 —12 —11 —1O —9
del 0—18

Figure 24. Mixing line of modern and paleowater.

 

 

 

75

Summary

Stable isotopes of hydrogen and oxygen are useful tracers in
hydrogeological investigations because they are generally considered
conservative in low-temperature environments. The stable isotope content of
ground water is generally expected to reflect the average local climatic condition
of the aquifer's recharge area. Paleowaters may be identified based on
differences in 6150 and SD, deuterium excess, or both.

Eleven water samples were collected from North Dakota State Water
Commission wells in Sioux, Grant, and Morton counties for 18O and D analyses.
The samples fall within three distinct groupings defined by d—excess values of
approximately 4, 7.5, and 10. However, the 6180 values show no correlation with
d-excess suggesting that, although three paleowaters are present in the study
area, they were precipitated under similar climatic conditions. The slopes of the
8180—8D graphs, plotted according to the d-excess groupings, are consistent with
both the North American meteoric water line and the local (Oakes, North Dakota)
meteoric water line. The slopes indicate that the ground waters are of meteoric
origin and unaffected by fractionating processes. Thus, evaporation prior to
recharge (e.g. proglacial lakes) is not indicated by the stable isotope data.

Two different paleowaters are present in the discharge area--a Iow-
chloride, high d-excess (7.5 and 10) water and a high-chloride, low d—excess (4)
water. All samples outside the low—chloride zone have d-excess values about 4,
suggesting a single source for these waters. The d-excess values for the water
in the low—chloride zone fall into two grouping, one around 7.5 and the other
around 10, possibly related to more than one recharge event.

Calculated temperatures for the samples using 8180 were 6.9 to 99°C

cooler (-16.1 to -14.1 6‘80) than modern precipitation (-9.3 8180) for all but one

76

sample, which yielded a temperature 4°C cooler (-12.3 6180) than modern.
Assuming the -12.3 8180 sample to be modern recharge, the Fox Hills aquifer
water samples exhibit temperatures 2.6 to 56°C cooler than modern.

A global circulation model and energy balance model suggest that the mean
annual temperature at 43°N latitude was about 4 to 75°C cooler than modern
during the last glacial maximum 18,000 years ago. Earlier glacial advances may
have occurred under similar climatic conditions.

The stable isotope investigation supports hypothesis (c), that the water in
the discharge area of the Fox Hills aquifer in Sioux, Grant, and Morton counties
is derived from local precipitation recharged during the Pleistocene. Hypotheses
(b) and (e), local precipitation/recharge and leakage from adjacent aquifers, are
not supported by the isotope data and this is consistent with the results of the
hydrogeological and hydrogeochemical investigations. In addition, hypothesis
(d) and (f), leakage from proglacial lakes and subglacial meltwater as the major
source of the anomalous water body, are not supported by the stable isotope

investigation.

 

 

CHAPTER 5: POSSIBLE PALEOHYDROLOGIC RESPONSES TO
PLEISTOCENE GLACIATION

Literature Review

Various researchers have suggested that groundwater flow patterns in
certain aquifers may have been altered during the Pleistocene because glacial
ice blocked their regional discharge areas, glacial meltwater was available for
recharge, and some geologic materials were compressed under the weight of
overriding ice sheets. The development of the glacial meltwater recharge
hypothesis is discussed below. An examination of the hydrology of glaciers is
then presented to expand the meltwater hypothesis to include snowmelt and rain

transported via the englacial drainage system.

Glacial Meltwater Recharge Hypothesis. One of the earliest

presentations of the glacial meltwater recharge hypothesis is the glacial-artesian
model proposed by McGinnis (1968) to explain the origin of Mississippi Valley-
type zinc—lead deposits. He notes that since ice sheets tend to move toward
topographically low areas they also tend to override and block regional
groundwater discharge areas. McGinnis suggests that a hydrologic connection
between the base of the ice sheet and groundwater in the discharge area might
develop, resulting in altered groundwater flow patterns and recharge of the
aquifer with meltwater.

Early studies, such as McGinnis's, attempted to explain groundwater
chemistry anomalies. Gilkeson et al. (1981) studied the hydrochemistry of the
Cambrian-Ordovician aquifer in northeastern Illinois and identified an
anomalously high enrichment of 348. They postulate that the anomalous water

was glacial basal meltwater injected into the aquifer due to the pressures

77

 

 

 

78

induced by the glacial ice overburden. Siegel (1983) also examined the problem
of anomalous water chemistry in the Cambrian-Ordovician aquifer, though on a
larger, regional scale. He presents a simple numerical model of glacial recharge
to the aquifer system that indicates flow paths could be reversed due to
glaciation. Filley and Parizek (1983) and Filley (1985) extended Siegel's work
by investigating the potential impact of the Wisconsinan Lake Michigan Lobe on
the Cambrian-Ordovician aquifer and two adjacent aquifers in northern Illinois
using a more sophisticated numerical model. The results of their model indicate
that rates and directions of groundwater flow may have been significantly
altered. During glacial advance, groundwater flow was reversed locally resulting
in the convergence of waters of consolidation (forced out of adjacent shale units)
with waters transported from the upgradient recharge area. During ice sheet
equilibrium, basal glacial water percolated into the groundwater system. Their
results supported Gilkeson et al.'s explanation of the anomalous water.

Recently, Siegel (1991) investigated a water chemistry anomaly in the
Cambrian-Ordovician aquifer of Iowa. He suggests that the anomalous water
body entered the deep aquifer as vertical recharge of subglacial meltwater from
the Wisconsinan Des Moines Lobe.

Recent studies have focused on the relationship of subglacial deformation
and subglacial discharge as a means of determining glacier properties. Mooers
(1990) presents a numerical model of the ice-margin thermal regime of the Rainy
Lobe in Minnesota. He calculates that subglacial meltwater production
exceeded the amount that could refreeze to the base of the ice sheet. Tunnel
valleys and eskers, which would indicate the presence of subglacial streams, are
rare along the portion of the ice margin studied by Mooers (1990). Thus, Moors
concludes that the excess water entered a subglacial aquifer as recharge and

then discharged beyond the ice margin. Another significant contribution is that

 

 

 

79

of Boulton and Dobbie (1993). They develop a theory of subglacial
consolidation that addresses the discharge of excess meltwater (i.e., through
channels, as a thin film, and/or by groundwater flow). Boulton and Dobbie
indicate that the subglacial drainage pathway is determined by the permeability
of the underlying geologic material and the water potential gradient. If the
glacier overlies an aquifer of high permeability and a water potential below that
of the ice, all the meltwater will enter the aquifer. They suggest that many such
aquifers have been overridden by Pleistocene ice sheets. However, if the
glacier overlies a less permeable material, at least some of the meltwater will
pond on the surface of the substratum and discharge by channel flow or sheet
flow. They applied the theory to both one-dimensional and two-dimensional
cases of subglacial groundwater flow depending on whether the ice sheet was
separated from the aquifer by a low permeability zone (e.g. till) or directly
overrode the aquifer, respectively. Boulton and Dobbie satisfactorily tested the
theory (both models) using data from field sites in The Netherlands and England.

As noted in the Introduction, the literature supports the possibility that the
Fox Hills aquifer was influenced by Pleistocene glaciation. In the USGS
Regional Aquifer System Analysis (RASA) report on the hydrogeology of the
NGPAS, Downey (1986) suggests the possibility of meltwater recharge and
altered groundwater flow patterns due to glaciation. He notes that during
Pleistocene glaciation, the regional discharge area along, and east of, the
Missouri River was covered by glacial ice that may have blocked discharge and
redirected flow to the southeast (Figure 25). In addition, meltwater at the base
of the glacier would have had significant potential for downward migration, i.e.,
temporary recharge may have occurred in the discharge area.

Hydrology of Glaciers. The studies presented thus far have assumed that

the glacial meltwater recharge is derived from melting at the base of the ice

 

 

80

EXPLANATION
7////A mat-um meg m

Limit pi Laurentide
ice at114,500 years 8. P.

/

--,’———-

 

° ‘00 200 MILES

l—rfi—H—I—J

° '00 zoomouerm

Figure 25. Inferred groundwater flow directions during Pleistocene glaciation
(Downey, 1986).

 

 

 

81

sheet. Surface water, however, is the most important source of water in
temperate glaciers (Shreve, 1972; Paterson, 1981). Paterson (1981) identifies
various sources for the water at a glacier bed (Figure 26), including surface
meltwater, rain, basal meltwater (geothermal and frictional), and meltwater from
heat of deformation. Surface meltwater, produced by ablation processes, and
rain commonly contribute several meters per unit area per year. Geothermal
heat typically melts about 6 mm of ice from the base of the ice, as does frictional
heat if the sliding velocity is about 20 m/a. Heat of deformation within the glacier
contributes a small amount of water.

During the melt season, water associated with temperate glaciers is
drained by a system that includes superglacial, englacial, and subglacial parts
(Shreve, 1972). The superglacial drainage follows surface channels, similar to a
river system, that eventually empty into moulins (vertical channels and cracks in
the ice) and crevasses that are part of the englacial system. Shreve (1972) has
likened the flow of water in the englacial system, which reaches from the ice
surface to its bed, to that of groundwater flow through karst terrain. Via the
englacial system, surface meltwater and rain may be transported to the glacier
base (Figure 26).

Water at the base of a glacier (subglacial) may be discharged as
sheetflow along the glacier’s bed, flow in channels or linked cavities along the
bed, groundwater flow through subglacial materials, or a combination of these
(Kamb, 1987; Boulton and Dobbie, 1993). The character and geometry of the
subglacial materials determine the rate of groundwater recharge. Where low
permeability material, such as till, overlies a highly permeable aquifer, water
drains vertically downward through the aquitard and into the aquifer. Flow in the

aquifer is assumed to be horizontal toward the glacier toe. If the aquitard

 

 

 

82

Emwzm
36390;.

atom
BEEF

      

.893 6826.5 328v? Looma B Edema:U oszocom .om 930E

.053 3:32.

:33 §>m0

cozsooam 38335

9338
\

Af 224 58398 $58

8:390 8.023%

  

mzaucoo

_m_om_ocm a
V mcwmm;

             

_
mBmoEonE *
:32“. .

ocoN
» 4 8:833 .235

flmccmco SEEEE
8_ _m_om_amaaw

8:23.85

oc__EE coszBma
2%:

goESocm

ucszcowmzom

‘ll'
83 co:m_n< $3 co:m_:E:8<

 

 

83

pinches out at the glacier terminus, the water will be discharged into the

proglacial zone (Boulton and Dobbie, 1993).

Data Analysis and Interpretation

Modeling the response of an aquifer to Pleistocene glaciation is a
speculative endeavor because of our limited knowledge of both the pre-
glaciation aquifer system and the ice sheet configuration and hydraulics.
Assumptions must be made that will dire—ctly influence the outcome of the
simulation. Thus, attempts at simulating an aquifers response to glaciation can
only indicate the feasibility of various postulated ways in which the aquifer could
have behaved under the specified conditions. The results of the simulations do
not provide quantitative information on the physical/conceptual system.

With these limitations in mind, the hydrologic responses of the Fox Hills
aquifer to glaciation-related stresses were simulated using a 2-D finite difference
model, SAM4 (Kinzelbach, 1986), with an iteration error limit of 0.05 m. The
simulations were first attempted assuming transient conditions; however, it
became clear that the system reached equilibrium in a short time, 150-200
years. Since glacial episodes probably occurred on the order of a few thousand
years, steady-state conditions were assumed for subsequent simulations. The
governing equation and model grid are the same as those presented in Chapter
2, as are the assigned transmissivity and initial water—level values. A new set of
boundary conditions are imposed on the model as discussed below. Four
simulations were conducted. First, the model was run with new boundary
conditions and without any additional stresses to test the validity of using the
new boundary conditions. Second, Lake McKenzie was added as a constant

head feature. Third, the discharge area was reduced in areal extent to mimic the

 

 

84

affect of the Verone ice sheet blocking discharge. Fourth, recharge was
assigned to grid nodes where the Fox Hills Formation subcrop was overridden
by the Verone ice sheet.

Simulation 1: present conditions. The present water-level distribution in
the Fox Hills aquifer was simulated using prescribed head boundaries on the
west and south edges of the modeled area, as before, but with no flow
boundaries along the north and east edges of the modeled area (Figure 27).
The northern boundary falls along a streamline and thus may be modeled as a
no flow boundary. The eastern boundary falls along the Missouri River. As
stated in Chapter 2 and shown in Figure 4, the Fox Hills Formation is eroded
away along much of the Missouri River valley and, as the main discharge area
for the aquifer, the Missouri River valley represents a hydrologic barrier. Thus
the eastern boundary may be modeled as a no flow boundary. Discharge nodes
were assigned as in the model in Chapter 2. The only difference between the
two simulations is the north and east boundary conditions. The simulated head
distribution (Figure 28) is similar to the observed head distribution. Groundwater
movement is generally eastward toward the Missouri River valley with deviations
toward the Cannonball and
Heart rivers valleys. The new boundary conditions are thus considered
acceptable for the following simulations of stressed conditions.

Simulation 2: Lake McKenzie. The first recognizable Late Wisconsin
glacial advance in North Dakota was most likely in its wasting stage when it
reached the south—central portion of the state (Bluemle, 1984). Drainage was
probably diverted southeastward along the Strasburg Channel until it was
blocked by the advancing ice sheet, resulting in proglacial Lake McKenzie
(Bluemle, 1984). In this simulation, it is assumed that Lake McKenzie is in direct

communication with the Fox Hills aquifer, so that the maximum affect of the lake

 

85

I prescribed head cell
a no flow cell

 

FBI-Ilia...-
{fill-III‘EQIIII

L_

O 3 6 12 18miles
p—y—q—Fdfird
O 5 10 15 20 25kilomolars

Figure 27. Finite-difference grid for Fox Hills aquifer simulation.

 

 

86

        
    

m.
v
0‘

“1 "
\ ӎ.

  

‘Iljlltj;

Tm

     

Figure 28. Simulated water levels in the Fox Hills aquifer.

 

87

on groundwater flow will be considered. Lake McKenzie was modeled by
assigning constant head values to subcrop nodes within the lake boundary
(Figure 29). A lake level of 549 m was assumed based on the present surface
elevation along the postulated lake boundary. Discharge nodes were assigned
as in simulation 1 with the exception that no discharge nodes were located within
the lake boundary. The resulting head distribution (Figure 30) shows the water
levels in the aquifer to be approximately 20 In higher than present conditions,
however, groundwater flow is still toward the east. Any recharge to the aquifer
from Lake McKenzie would be transported eastward toward the Missouri River
valley where it would be discharged from the aquifer. Thus, leakage from Lake
McKenzie can not explain the anomalous water chemistry in the study area.

Simulation 3: blocked discharge area. The age of the Verone glaciation is
unknown, but has been inferred to be late pre-Wisconsin or Early Wisconsin
(>65,000 a). Calculations of ice thickness (based on Mathews, 1974; Table 2)
suggest that the ice sheet was less than 150 m thick in the study area and
generally less than 100 m thick over the the present Fox Hills subcrop, with an
ice overburden pressure less than 91 m equivalent water (ice thickness x 10l11)
at the land surface. As water levels in the aquifer’s recharge area in
southwestern North Dakota are z300 m (1000 ft) higher than those postulated in
the Verone ice sheet, the affect of the overridding glacier on flow in the aquifer
should be localized.

The potential postulated for the ice sheet is greater than the water levels
presently observed in the aquifer in the study area. Inferring similar aquifer
water levels for the past, groundwater discharge would most likely have been
blocked by the ice in the discharge area in North Dakota and diverted southward
to the unobstructed discharge area in South Dakota. In this simulation,

discharge only occurs from nodes along the Cannonball and Missouri river

 

 

87

on groundwater flow will be considered. Lake McKenzie was modeled by
assigning constant head values to subcrop nodes within the lake boundary
(Figure 29). A lake level of 549 m was assumed based on the present surface
elevation along the postulated lake boundary. Discharge nodes were assigned
as in simulation 1 with the exception that no discharge nodes were located within
the lake boundary. The resulting head distribution (Figure 30) shows the water
levels in the aquifer to be approximately 20 m higher than present conditions,
however, groundwater flow is still toward the east. Any recharge to the aquifer
from Lake McKenzie would be transported eastward toward the Missouri River
valley where it would be discharged from the aquifer. Thus, leakage from Lake
McKenzie can not explain the anomalous water chemistry in the study area.

Simulation 3: blocked discharge area. The age of the Verone glaciation is
unknown, but has been inferred to be late pre—Wisconsin or Early Wisconsin
(>65,000 a). Calculations of ice thickness (based on Mathews, 1974; Table 2)
suggest that the ice sheet was less than 150 m thick in the study area and
generally less than 100 m thick over the the present Fox Hills subcrop, with an
ice overburden pressure less than 91 m equivalent water (ice thickness x 10/11)
at the land surface. As water levels in the aquifer’s recharge area in
southwestern North Dakota are s300 m (1000 ft) higher than those postulated in
the Verone ice sheet, the affect of the overridding glacier on flow in the aquifer
should be localized.

The potential postulated for the ice sheet is greater than the water levels
presently observed in the aquifer in the study area. Inferring similar aquifer
water levels for the past, groundwater discharge would most likely have been
blocked by the ice in the discharge area in North Dakota and diverted southward
to the unobstructed discharge area in South Dakota. In this simulation,

discharge only occurs from nodes along the Cannonball and Missouri river

 

88

- prescribed head cell
0 no flow cell
1,. o discharge cell

   

  
 

‘I

   
     
  
 

  
  
       

IIIIIIIIIIIIEIIIIIiK QIIEII
IIIIIIIIIIIIIEEIEEQ Wfl/Afl
IIIIIIIIIIIIIIRQIIIVQJZWI
IIIIIIIIIIIIIMHIIII Ill/IL“.
GEE.IHIIIIIIIEIIIIIIfiflfl/lmumm
IIIIImIIIIIIEIIIIIIII'QQZQ
"IIIIIIIIE=MMIIIIIIIIIfi9Q
IflIIIIIIIEIIIMIIIIIIIIIMfiZ
IflIIIIIIIIIIIMIIIIIIIIIMQ/
IMIIIIIIIIIIIMIIII IIIEWufl
IHIIIIIIIIIIIMIIII/ I99; 9“
IHIIIIIIIIIIIEEEEIQQDf””‘k
IHIIIIIIIIIIIIIHHflflllflflflflZ
IEIIIIIIIIIIIIIIE? IIHIBQE
flIflIIIIIIIIIIIIIfi'
flIflIIIIIIIIIIIIflI
flIflIIIIIIIIIflflEII
IIflIIIIIIIIIPEIII
IIIEEZIIIIIEEIIIII

  

o 3 6 '12 Iemiies
W
o 5 1015 20 25kilomolors

Figure 29. Finite-difference grid for simulating the influence of
proglacial Lake McKenzie.

 

 

w

CORSON

 

0 3 6 12 18miles
H—H—fi—v—l
o 5 1015 20 25kilomelers

Figure 30. Simulated water levels, taking into account Lake McKenzie.

 

 

 

90

. I prescribed head cell
0 no flow cell
1, o discharge cell

 

DAIREHIIM

IIIEfiIIESIBQK
flIflIIIIIIIIIIIIIflflflflflhwlflfl
IIflIIIIIIIIIIIIfiIIIIflIEW ufifl
IIflIIIIIIIIIIBJIIIIIIIIQQI
IIflIIIIIIIIHEflIIIIIIIIEfiII
IIEEflIIIIIIEIIIIIIIIIIHQII
IIIEMIIEEEIIIIIIIIIIIIIhfiI

0 3 6 12 18min:
WW
0 5 1015 20 25kllomclor|

Figure 31. F mite-difference grid for simulation of the Verone ice sheet partially
blocking the discharge area.

91

valleys south of the Verone Ice Margin (Figure 31). The simulated head
distribution (Figure 32) shows groundwater flow diverted to the south toward the
unobstructed discharge area in south-central North Dakota and north-central
South Dakota. This is consistent with Downey’s (1986) hypothesis that
groundwater flow would have been diverted to the southeast during the
Pleisotocene when the regional discharge areas were blocked by glacial ice.

Simulation 4: subglacial recharge. Large volumes of snowmelt and rain
would have been transported to the subglacial system of the Verone ice sheet
via the englacial system. This water would have had the potential to move
downward into the underlying aquifer. Two possible hydrologic scenarios are
postulated. The first assumes the water at the ice-bed contact to be unconfined;
the second confined/pressurized.

Scenario a: As the Verone ice sheet advanced up the Missouri Slope and
associated escarpments, it may have become compressed with resultant
shearing in the ice, similar to the Late Wisconsin Lostwood ice advance that
overrode the Missouri escarpment (Moran et al., 1976). Debris beneath the ice
would have been carried to the ice surface along shear planes in the glacier as it
moved onto uplands (Figure 33). As the stagnant ice melted, glacial sediment
would have accumulated on top of the ice insulating the ice so that it took
thousands of years to melt. During this time, the stagnant ice would have
behaved as an unconfined aquifer. Rain and snowmelt would infiltrate into the
fractured ice each year from spring through fall, establishing a water table of
local meteoric water. A potential for downward water movement would have
existed. Recharge of the underlying Fox Hills aquifer through the glacial debris
may have occurred for thousands of years.

Scenario b: As the Verone ice sheet advanced over the Missouri Slope,

cavities would have formed in the ice at the ice—bed interface (Figure 34).

 

W

 

CORSON

0 3 6 12 18miles
p—y—.I,_,_.~_,—I
0 5 1015 20 25kllomelers

Figure 32. Simulated water levels, taking into account the partially
blocked discharge area.

 

 

 

93

\ \ (
\ \Sragnant Ice
\

\

 

Figure 33. Schematic diagram of a glacier advancing over an escarpment
(after Bluemle, 1977).

 

94

Bedrock

 

Figure 34. Linked cavity drainage system (Kamb, 1977): a) map view,
b) cross-section.

 

 

95

 

CI:4m2/d

O 3 6 12 IBmllos
p—q—Pfifi
o 5 1015 20 25kllomelor:

Figure 35. Modified transmissivity distribution.

 

 

 

96

During late spring through fall, snowmelt and rain moving from the ice surface
through the englacial system would have entered the cavity system. In such a
system, numerous small cavities are linked by orifices that restrict flow and
induce water storage (Kamb, 1987). Increasing volumes of water from the
surface results in increased water pressures in the cavity system. Water
pressures in the cavity system are generally considered to be slightly less than
the overburden pressure (Kamb, 1987). During winter, water in the linked cavity
system would continue to be under pressure, although without a renewable
water source (similar to a falling head permeameter). A potential for downward
water movement through the glacial sediment at the bed would have existed.
Recharge of the underlying Fox Hills aquifer may have occurred for the duration
of the ice coverage. If the linked cavity system became unstable (i.e., too much
available water), a conduit system would develop from the enlargement of the
cavities. In this case, water would move quickly through the system with a low
hydraulic head. Then as discharge declined in fall, the conduit system would
close leaving the linked cavity system from late fall through spring.

Thus it is feasible that snowmelt and rain recharged the Fox Hills aquifer
in its discharge area during the Verone glaciation. This hypothesis is tested by
the fourth simulation.

It is assumed that the Verone Ice Margin was stable for a sufficient period
of time such that steady-state conditions apply. It is also assumed that the Fox
Hills Formation has been eroded along the Missouri River subcrop area since
the Verone glaciation. For this reason, the sandstone thickness used in the
model was modified along the subcrop such that the minimum thickness is 21 m
(Figure 35) and the minimum transmissivity 12 m2/d (0.57 m/d x 21 m).
Previously identified discharge cells (simulation 3) were assigned a value of .5

mm/yr. Recharge cells were determined by identifying the subcrop discharge

 

97

I prescribed head cell
ono flow cell
odischarge cell
A recharge cell

 

IIIIBUEERmflN
IIIIILflflIPWUN
EEEEIflfimflEIHW
IIIIEAIEEIH“

IIEAIIDWEIQ

IIIIIIIIIII
EEEEEIEIIII
IIIIIIEIIII
IIIIIIEIIII
IIIfiIIIIIII
IIIHIIIIIIB
MIIIIIIIIIIIIIIIIKI

I
F
I
I
I
I
I
I
I
I

EEIIIIIIIIIIIIIEQEI

snags!-
IImama-suEIlIlIIIIIIlaahnI

0 3 6 12 18miles
)—~_~_I_.i1_,_i
O 5 1015 20 25kilomolers

Figure 36. Finite-difference grid for simulation of the Verone ice sheet
contributing recharge.

 

 

 

98

cells from the original simulation (Chapter 2) that would be overridden by the
Verone ice sheet (Figure 36). Recharge was varied within specified limits (Table
2) to produce an acceptable water level distribution within the aquifer. An
acceptable water-level distribution was defined as water levels in the aquifer
less than the ice overburden pressure water equivalent head so that recharge
rather than discharge would occur. The recharge values were constrained by
the thickness of the ice and the inferred hydrogeologic system.

Ice thickness was calculated for nodes using Mathews (1974) equation
(Table 2). Heads associated with the ice were calculated for ice overburden
pressure water equivalent (maximum gradient; confined, linked cavity system)
and 50% ice thickness (minimum gradient; unconfined, stagnant system). A
level ground surface of 550 m was assumed based on the present upland
surface elevation in the study area adjacent to the Missouri and Cannonball river
valleys. A hydraulic conductivity of 1045 m/d was assigned for the glacial till
capping the aquifer assuming the till was derived from shale and siltstone. The
thickness of the glacial till was estimated to be 30 m. Recharge values of 1.0
and 1.4 mm/yr were calculated (Table 2) and were used to constrain the
possible recharge values input to the model.

Recharge of 1.4 mm/yr was too large to produce acceptable heads in the
aquifer. The water levels in the aquifer beneath the recharge nodes were higher
than the ice overburden water equivalent head. Recharge of 1.0 mm/yr did
produce acceptable heads in the aquifer. The resulting head distribution (Figure
37) shows mounding of the water levels (below the ice overburden water
equivalent head) in the aquifer beneath the overridden subcrop. A temporary
groundwater divide separates ambient groundwater flow from the west and the
newly recharged water in the east. No attempt was made to fit the eastern flow

regime to the chloride distribution as that would imply that the simulation results

 

 

 

    

E on \ 2:... wow

 

 
 

wwocxoit
--iii|liim%im E UquwioflgimwwieflgxViulWWwIUOE_:28 wwumcoom

 

3:03:50 2356 c .6 w_ .cEccoo .8! .EEsmwm

 

 

 

     

l ll lilllllwllli

99

It:

I

Eomm “a _m>o_ w_ 8326 ocsouiolumfi cozmoc_._QE_m co wwwmmioe E conm>m_o .06;

H BNEWQmmm 2m Iotsdm m___I xou c. mc.o_um>o_m 6am;

 

  

 

$05.25 02 x wd ”mic 39.93030 A392 63%. .EEV 02 5 .mth3 Imam; comm

wwoconuMB x 920.5. ”mm Imam.:o._ww 390; I28». .wammcoflmmmJUm Iofizfldcusego mo.

3558150: 85235.8 x mg #83 3252 332.2 38.8.8 mmocxgsog

 

 

  

   

 

£992 0.0. omocw> IQ kuszwo cammcflrcot boa—3&0

 

 

 

 

 

camcoom 23: ._o cos—gem. Ioum>>

 

 

 

 

 

     

 

 

 

I926 8_ c. 2.5: .2“;

 

     

wmmconH oo. 5.82 So: oocflmfi

 

.86. @9398 @0233 do coszzmm .N 9an

 

 

 

100

 

0 3 6 12 thiles
H—l,._,_.~——J
O 5 IO 15 20 25kilomelers

Figure 37. Simulated water levels, taking into account recharge from
the Verone ice sheet.

 

 

 

[01

provide quantitative information on the physical system. As stated above, the
simulation merely shows that temporary recharge in the discharge area during
glaciation is feasible. A more detailed model, with better defined northern and
southern boundaries and ice sheet configuration, may allow for such “fitting” in
the future. Though speculative, recharge of the Fox Hills aquifer by snowmelt
and rain input under an ice sheet (2 ice sheets are known to have overridden the
study area, only one was simulated) is presently the best explanation for the
observed chemistry anomaly.

lntergretation. The above simulations show that partially blocking the
discharge area of a regional aquifer could alter groundwater flow patterns as
suggested in the literature. Temporary recharge in the blocked discharge area
would provide fresh meltwater to the system. In some cases, this recharge might
result in mounding of freshwater in the discharge area and, consequently, the
formation of a temporary groundwater divide separating the ambient upgradient
water from the newly recharged meltwater. Proglacial Lake McKenzie
apparently would not have influenced the flow regime sufficiently to divert
groundwater flow to the southeast or to input fresh water in the aquifer

upgradient of the lake.

Summary

Various researchers have suggested that groundwater flow patterns in
certain aquifers may have been altered during the Pleistocene because glacial
ice blocked some regional discharge areas, subglacial meltwater was available
for recharge, and some geologic materials were compressed under the weight of
overriding ice sheets. Ice sheets tend to move toward topographically low areas,

which are often regional discharge areas. Groundwater discharge becomes

 

 

102

blocked by the overriding ice sheet, resulting in altered groundwater flow
patterns. If the glacier overlies an aquifer of high permeability with a water
potential below that of the ice, all the meltwater would enter the aquifer,
whereas, if the glacier overlies a less permeable material, at least some of the
meltwater will pond on the surface of the substratum and discharge by channel
flow or sheet flow.

Water at a glacier bed has various sources, including surface meltwater
(produced by ablation processes), rain, basal meltwater, and meltwater from
heat of deformation. Surface meltwater, combined with rain, however, is the
most important source of water in temperate glaciers. During the melt season,
surface meltwater and rain may be transported to the glacier base via the
englacial system. Water at the base of a glacier (subglacial) may be discharged
as sheetflow along the glacier‘s bed, flow in channels or linked cavities along the
bed, groundwater flow through subglacial materials, or a combination of these.
The character and geometry of the subglacial materials determine the rate of
groundwater recharge. Flow in the aquifer is assumed to be horizontal toward
the glacier toe.

A 2-dimensional finite difference groundwater flow model was used to
simulate the response of the Fox Hills aquifer to continental glaciation as a
means of assessing the feasibility of the glacial meltwater hypothesis.
Compression of shale units was not considered. As stated above, modeling the
response of an aquifer to Pleistocene glaciation is a speculative endeavor
because of limited knowledge of both the preglaciation aquifer system and the
ice sheet configuration and hydraulics. The Fox Hills simulations merely show
that temporary recharge in the discharge area during glaciation is feasible.

The simulations suggest that (1) proglacial Lake McKenzie probably would not

have influenced the flow regime sufficiently to divert groundwater flow to the

 

 

103

southeast or to input fresh water in the aquifer upgradient of the lake, (2)
partially blocking the discharge area of the Fox Hills aquifer could alter
groundwater flow patterns as suggested in the literature and (3) temporary
recharge in the blocked discharge area could result in mounding of freshwater in
the discharge area and, consequently, the formation of a temporary groundwater
divide separating the ambient upgradient water from the newly recharged
meltwater. Though speculative, recharge of the Fox Hills aquifer by snowmelt
and rain input under an ice sheet (two ice sheets are known to have overridden
the study area, only one was simulated) is presently the best explanation for the

observed chemistry anomaly.

 

 

 

SUMMARY AND CONCLUSIONS

Six working hypotheses/potential water sources were tested using
hydrogeologic, hydrochemical, and stable isotopic methods. The results of
these investigative techniques will be discussed with respect to each of the

potential sources. The overall conclusion and recommendation follow.

Upgradient Aquifer Water

The water-level maps of Lobmeyer (1979) and this study show that the

water in the discharge area of the Fox Hills aquifer should be ambient
upgradient water transported from the aquifer’s recharge area along the North
Dakota-Montana border. However, the hydrochemical facies and the chloride
distribution maps show that a separate water body is present in the discharge
area and that this water could not have been derived from upgradient aquifer
water. Thus, water in the discharge area does not have upgradient water as a

significant source.

Local Precipitation/Recharge

The hydrochemical data indicate that the water in the discharge area is
much lower in chloride than upgradient water, suggesting that mixing with
freshwater has occurred. The chloride distribution in the aquifer suggests that
the fresh water source contributed about 90% of the present water in the
discharge area. In the southeastern corner of Grant County, the chloride
concentrations drop from >6 meq/L to <1 meq/L in a 6 km stretch along the

groundwater flow path. in order to bring about this decrease in the chloride

104

 

 

 

 

105

concentration (by mixing with fresh water), a 500% increase in the volume of
water would be required as the water moves downgradient through this region.
Such an increase in the water volume would require recharge on the order of 4.3
to 8.5 mm/yr, only in a narrow, 6 km, stretch of aquifer. Neither the literature nor
the water-level maps of the aquifer suggest any unusual conditions that are
restricted to this region. Thus, it is unlikely that local recharge under present
climatic conditions could explain this increase in water volume. in addition,
mean annual air temperatures calculated from the stable isotope data indicate
that the water in the discharge area was precipitated in a cooler climate than
modern. Thus, dilution with local precipitation does not explain the chemistry
anomaly and modern local precipitation is not considered a significant source of

water to the discharge area.

Local Precipitation during the Pleistocene

The hydrochemical and stable isotope data indicate that at least two
paleowaters are present in the discharge area—a low-chloride, high d—excess
water and a high—chloride, low d-excess water. Assuming that the 42.35180
sample represents modern recharge, the Fox Hills aquifer water samples exhibit
temperatures 2.6 to 5.6 C cooler than modern. This suggests that the water in
the discharge area was recharged during a cooler climatic condition, such as
was prevalent during Pleistocene glaciation. A global circulation model and an
energy balance model suggest that the mean annual temperature at 43 N
latitude was about 4 to 7.5 C cooler than modern during the last glacial
maximum 18,000 years ago. Earlier glacial advances may have occurred under
similar climatic conditions. The possibility that local precipitation during the

Pleistocene may have been the main source of recharge to the Fox Hills

 

 

 

106

discharge area is dependent on identifying a feasible recharge mechanismuone
that is not operating today.

One can speculate that local precipitation falling on the ablation zone of a
temperate ice sheet would be transported via the englacial system to the ice-bed
contact. A significant potential for downward migration of this subglacial water
would exist. If the ice sheet overrode permeable material, some of the
subglacial water would discharge into the aquifer. The results of the simulation
of the Verone glaciation, though speculative, support this hypothesis. Water
levels in the Fox Hills aquifer where recharge occurred were raised sufficiently to
produce a mounding affect with a resultant temporary groundwater divide
separating ambient upgradient water from the newly recharged fresh water.
Although the hydrochemistry and stable isotope data strongly indicate that a
paleowater was recharged to the Fox Hills aquifer during cooler climatic

conditions than modern, the mechanism of recharge is speculative.

Leakage from Proglacial Lakes

The presence of proglacial lakes would provide a significant potential for
downward migration of water, and proglacial lakes are known to have existed in
the study area during glacial advances. Lakes are subject to evaporation even
with short exposure time; however, the stable isotope data indicate that minimal
evaporation occurred prior to recharge. Thus, proglacial lakes are not
considered a significant source of water to the discharge area. Although
speculative, simulation of the Fox Hills aquifer with Lake McKenzie as a constant
head feature supports this interpretation by showing that groundwater flow

directions would not be significantly altered by the presence of the lake and that

107

any recharge from the lake would be transported eastward to the Missouri River

valley discharge area.

Leakage from Adjacent Aquifers

The water levels in the Dakota aquifer (the first aquifer below the Fox Hills
aquifer) in south-central North Dakota are higher than those in the Fox Hills
aquifer, indicating a potential for leakage into the Fox Hills aquifer. However,
based on hydrochemistry data, leakage from the Dakota aquifer into the Fox
Hills aquifer would be expected to increase, not decrease, the chloride
concentrations in the discharge area. Thus, leakage from the Dakota aquifer
does not explain the low-chloride anomaly. The water levels in the overlying
Hell Creek aquifers generally are higher than those in the Fox Hills aquifer,
indicating a potential for leakage into the Fox Hills aquifer. However, the
discontinuous sandstone beds within the Hell Creek Formation are typically
perched or semiperched aquifers where downward migration of water is
restricted. Thus, leakage from adjacent aquifers is not considered a significant

source of recharge to the discharge area.

Basal Meltwater

Basal meltwater input under the glacier through the Fox Hills Formation
subcrop would provide both a source and a feasible mechanism for temporary
recharge in the discharge area of the Fox Hills aquifer. The subcrop is known to
have been overridden by two glacial advances, the Dunn and Verone

Glaciations, each of which may have consisted of more than one pulse. The

 

 

108
stable isotope values however, are heavier than expected for glacial ice.

Assuming that the observed 8180 values in the discharge area (average = -15.1)
are the result of mixing modern local recharge (-12.3) and subglacial meltwater
(-30), 84% of the 18O is contributed by the modern local recharge and 16% by
basal meltwater. If the 8130 value of the local precipitation recharge was lower
than -12.3 during the Pleistocene, an even smaller contribution would come from
basal meltwater. Thus, basal meltwater is not the sole or main source of
recharge to the aquifer. This is to be expected as surface meltwater, consisting
of snowmelt and rain, is the most important source of water in temperate
glaciers. Water at the bed of a glacier is thus primarily surface meltwater with

smaller amounts of basal meltwater.

Conclusion and Recommendation

The results of this investigation point to only one main source for the
anomalous water body in the discharge area of the Fox Hills aquifer in south-
central North Dakota: local precipitation recharged during the Pleistocene. It is
speculated that local precipitation was recharged in the discharge area due to
the hydraulic gradient imposed by an overriding ice sheet.

Further testing of this hypothesis is advisable. Dating water in the Fox
Hills aquifer along a flowline from recharge to discharge area would provide

considerable insight into the dynamics of the aquifer system. Dating water from

 

 

 

109
the anomalous water body in the discharge area would provide time constraints

on the recharge events and thereby further test the feasibility of the glacial

meltwater recharge hypothesis proposed here.

 

APPENDICES

110

Appendix A. Geologic data.

Table 3. Geologic data derived from drill logs.

Location W Glacial De oosits
mum
---___—

4521 129N -23 ddd resent 24.4

4520 129N 81W 01 bab subcro resent 21.3
810510 bbb overlain absent

4490 129N 87W 10 bbc overlain absent
4525 129N 88W 05 ddd overlain absent
8081 Fl30N 79W 19 ccb I absent oresent

8077 130N -03 abb absent resent

8080 130N 80W 23 ddd absent resent
8082 130N 80W 26 baa | subcrop present
8083 130N 82W 36 bbc . overlain absent
4522130N 83W 36 aaa l‘overiain absent

 

 

 

 

 

 

4523 130N 84W 31 aaa

absent

 

4489 130N184W 36 aba

overlain absent

 

new 64 bbb

l
l
overlain 1
.1

overlain absent

 

8097 130N 85W 17 add

absent

 

4488 130N 85W 17 daa

overlain
overlain

absent

 

4524 130M 86W T28 ccc
4492 130N 89W 32 dda

l
T
1

absent
absent

overlain
overlain

 

8075.131N 80W 06 bed
8642 131N 80W 16 ddd

subcrop
absent

present
present

 

 

 

8079 131M 80W 33 baa
8641j_131N 81W 01 dad
8076j1§_1N 81W 01 dda

451 131N 82W+18dcd

absent present

subcrop fli present '

present
absent

subcrop

overlain

 

2;

4413131NL83W 11 bab

4410 131N “84W 02 aaa
32 aaa

L
80941131 N 85W
32 daa

i

L
jf

l

l

 

overlain
overlain 7L
overlain 1
overlain

ppesent
absent
absent
absent

 

l
30 aaa

overlain . absent

 

80951131 N 185W
452611 31 N 89W
8640 132N 180W 16 000

subcpgp ' present

 

80741132N 80W {27 ddd .

l

overlain
subcrop

present
present

 

8073 132N-sow jss abb
_4418*132N,81W 29pbbb
4419.132N 81W130 aac

 

 

subcrop
subcrop

present
present

 

subcrop absent

 

4421*132N 1{81w jso cdc

4420 132N 81W [30 dbb ‘

subcrop present

 

_4415*132N 82W [09 ddd

4416 132Nj82W i1OCbb '

,4417 132st2w i10cbc

1

absent
present
present

overlain
subcrop
subcrop

l

 

 

 

8084 132N I82W l10 cdd

 

overlain absent

 

 

 

 

 

111
Table 3 (cont’d).

   
   
 

_1mmm_-
m-nm—_
---———
mm

       
    

mm:
mm
subcror> present
resent
MW

  
 
    

8087 132N 83W 36 ccc subcro- resent

8648 132N 84W 01 ccd overlain oresent
4406 j132N 84W "01 daa subcro- resent

   
 
  
  
  

  
   

  
   

 

  
  

 

 

 

   
  

 
     
 

    
  
  

8645|132N l84W 01 ddc subcrop present
4398 132N r84W 06 ccc overlain present
overlain absent

     

8
=132N 84W 12 baa

subcrop

 

    

 

    
   

 

 
  

 

4407 4132N [84W 12 ccd l subcrop I present
4518 *_1_32N i84W 16 daa 4| overlain : absent
4408 132N 84W 25 bab I overlain ' absent
8104 132N 87W 26 ccb overlain absent

   
 

 

  

4491 132N
4528132N 88W 04 cbb

      
    
  
 
 

    
   
   
   

   
  

  
  
 
   

 

 

 

 

   

overlain absent
8635l133N 79W subc_rpp present
8068 133N 79W subcro oresent

  
 
 
 

8072 133N 79W overlain
8636 133N 79W 11 baa I subcro.
8639 133N 79W 29 aba subcrop

 

       
 

 

  

present

 

 

    

 

  

806E51133Ni80W 01 ddd l subcrgp i present
80701133Nl80W |12ddd l subcrgp | msent
8071 ,133Nl80w 13 dda 7 subcrop ir present

 

 

 

     

 

      

 

 

 

   
  

 

 

 

 

 

   
  
  
 

 

   

 

   

8644T133N180W 131- ccd T subcrpp l mient
8653-1133N I83W J05 dcc j overlain absent
43991133N {83W |07 ccb l subcrop J present
86521133N 83W 08 bbb I subcrop present
86551133N 83W 12 ada { subcrgp J present
8654—1133N 83W I.14 bbb subclpp present
44001133N 83W .17 cbbT subcrop pfesent
_44O14133N 83W t:17 daa . subcrop : present 7
4403|133N183W ,21 aaa overlain present
74402|133N 83W j21abb l subcrop present ..
4404j133stsw j28 aab J subcrop 7 present
74405|1p33N 83W 28 dcd subcrop present
I

overlain
subcro-

8649l133N 83W L33 ddc

present
8650 r1 33N 84W

. resent

  
 

 

  

 

01 dcc

     

 

 

 

112
Table 3 (cont’d).

   
   
 

—E§IIEIIEI_-
---
--03 dad I overlain resent

-133N 85w absent
absent
133N absent
1 N 79W 29ddd subcrop present
resent
-134N 79W resent
--m resent

8637|134N 79W 32 dad I subcro- uresent

8928134N-32ddd subcro

8634 134N (79w 34 cbb subcrop
8638|134N 80W {35 ada subcrop

8085134N 82W 36 cdc j overlain

8086 134N 82W 36 dcd overlain
4517134N 85W 03 bcc l overlain absent

8098T1_34N ,85W 06 bcc overlain absent
4516 134N 85W 21 bab overlain absent

 
 

 
   
     
     
 

 
         
   

  

     
 

  
 
    

   

 

 

   
 
  

 

  
 
  
  

  

 

    
   
  
    
   
   
    
   
 
   
  

 

   
 
   

    
  
  
      
   
 
    

   
 
    
 
 
  

  

 

 

 

 

   
    
  
 
  

4493 134N overlain absent
8102 135N 86W 07 ddd overlain absent
4515 135N overlain absent

4514135N 86W 26 bbb - overlain absent

 

 

 

89W overlain absent
90w 23 bbb overlain absent
05 abb overlain o resent

8099 136N 85W 08 ddd + overlain present

   

 

   

 

8100l136N 85W T09 bcd overlain present

,

     
  

   
 

      
 

    

    

 

 

   

    
 

 

 

   

 

   

 

   

 

   

 

 

 

 

    
 

 

   

 

   

 

    
  
    
 

 

 

   
 

    

 

  

 

4512 136N 87W 07 ddd overlain absent
44L8§fl36N 87Vl_136 abd ' overlain
4513‘136N 88W 13 aaa , overlain
4485|137N 88W 21 ddc , overlain
4511—1937N WJQQ aba overlain absent
4510;137N 'LQOW 30 aac T overlain absent
4569 133Nl82W 05 dba j subcrg) present
45721134N ifs—w 07 bob 4 subcrop , present
92961lT34N 79w 417 adb , subcrop 'j present
9295|134N 79W I20 aab l absent i present
4571'134N180W l16daa I subcrop I present
9292'134NFOW 17 ccb ‘ overlain j present
“92931134N 80W L19 daa ‘ subflp j present
9294l134N Isow 30 ccc , subcrop j present
89941134N 80W J23 baa l subcro ' present
8993j134N 80W :23 bab k subcrop L present
8995|134N481W 24 add subcrpp present
89901134N 81W 25 dab subcro oresent

 

       

113
Table 3 (cont’d).

W
----_—
mm
mm

4565 134N 83W [17 ccc overlain I resent
overlain resent
26 bba overlain . resent

4567 134N 83W 32 aaa overlain present
4562 134N 84W |01 cdc overlain i present
4563 134N 84W 03 add overlain i resent

4564134N 84w iiddd

       
   
     
   
   
     
 

 
     
    

 

   

 

 

      
      
     

     
     

 

    

 
 
 
    
 

 

   
 
  
   

 

 

 

 

 
  
 

 

 

—84W I13 bbc l overlain present
8968,134N 84W ,13cbb overlain uresent
8969 134N 84W ‘24 bbb overlain present
47691 135N179W i10aab i overlain 1 absent

135N|80W 30 aab l overlain 1 present
4135N7I:80W 33 dda i subcrop T present

-135N 80W L3_6 aaa j overlain { absent

l

  
 
 

4-576i135N 81W 102 ccd
8-997 1-35N 81W 03 cbb7i
4577 _3SN 81W 11 aba—i

9289135N 81W 11ddd
9291135N81W12cdd
81W 14830

9328 135N 81W (24 ddd

overlain . resent
overlain present

overlain resent7
overlain present
overlain i present
overlain ‘ o resent

overlain present

    
 
       
 

    
  
   
   

 

   
   

  

 

  
       
  

 

   
  
  

  
    
  
  

 

 

 

   

 

 

   

 

   
 

 

     

 

      

 

 
    

 

    
 

 

      
      

 

 

 

    
 

 

 

 

      
 

    

  
    

 

 

 

8987l135N 82W 15 aaa overlain absent
8986 135N 82W 22 bcb overlain i present
4560 13511782W 730 cbb J overlain L prese ent
4559 135N 83W 520 ccb overlain present
4768 135N 83W7,32 cbb overlain present
4556[135N784w 04 dcc__l_ overlain i present 7
89781135N Lg4w 09 ccd overlain 7 present 7
8977i135N 84W T15 bba overlain present
8971 135Ni84W ,16aaa overlain i present 7
8982135NL84W j_16aad ‘ overlain ‘ present
8972|135N 84W 16 abb overlain 7 7 present
4557 135NT84W 21 ddd i overlain i 7 present '
4558135Nj84W '26 daa 71 overlain 77‘ present 7
8962j135Nj84W 36 dcd overlain 7 i7 7 present777
8963135N|84W 36 dda j overlain fl 7 present
4770 136N+79W 105 ccc J7 overlain 77' 7 absent
4590(136N 81W 1'06 bbb a overlain : present 7 77
9286 136N 81W 07 aaa subcrop 77 present7777 7
4591 136N 81W 07 bbb overlain oresent

 

 

     

 

 

 

114
Table 3 (cont’d).

—W Glacial De- sits

m-nm_—

---—_
4771 136N 81W 07 ddc overlain resent

16 bbb
136N 16 cdd subcrOo ~resent

3
9288i136N|81W 21 ccd l subcrOo resent
4579 136N 31 abb resent
582

-82W 04 aaa
N

   
       
   
    

E

 
    

  
        
            

     
   
 
 
 
  

 

4586 136N 83W 01 ccc overlain

  
 
 

 

   
 

 

present
4553 136N 20 dba overlain absent
4554l136N |84W 30 daa i overlain i7 absent

 

 

a over aln resent
4555136N 84W 31 dd | ' 11 p

9011 137N 80W 08 cdc overlain
16 dbb overlain

 

 

90101137N180W
9007i137N i81W 1o baa l overlain p
9006 137N 81W 16 aaa—1 overlain present

9329137N 81W 21 aca overlain
9383 137N 81W 28 ccd overlain
4589 137N 81w 131 ddd overlain
9284'137N 81W 32 baa‘i overlain

7

 

  
 

  

 

   

 

 

     

 

  

 

   
 

 

   

 

  
 
 

 

 
  

 

 

 

    

 

     
  

 

 

    

 

    
    

 

 

     

 

     

 

   

 

 

 

 

   

 

 

 

   

 

   

 

   

 

   

 

 

   

 

 

   

 

 

 

    
 

137N 81W 32 bbb overlain p present
9003 137N 82W 20 daa overlain resent
9002 4137N 82W 21 ccc—jr overlain i ppresent
4585 137N 82W p32 dcc * overlain I present
4584i137N |82W 33 dcc overlain 1 present
458—_3+7T137N 82W 35 ccc T— overlain present
4581 137N 82W 36 ddd overlain present
4763i137N 83W % cdd i overlain 1 present
45_52j137Nl§3W}0_7 bba t overlain + absent
4587 137N 83W 24 dda overlain ; pre_7sent

.7" . l
4551 l137N 85W 06 ccd 7+ overlain L present
9304i137N |85W 17 cdb overlain 4 present
475217137Ni86w 103 aad i overlain J present
4757 137N4§7W 12 cda i overlain 7 present
2908 138N |80W 06 bcc overlain absent
29091138N |8OW730 ccc ’ overlain J absent :7
47501138N i81W 09 abb 4 overlain absent
7 90147138N181W J12 dab , overlain present 7

9012 138N 81W 124 dcd overlain present
90091138N [81W 35 aba overlain present
9008 i1 38Nj81W 35 baa 1 overlain ' present
9004 I138N [82W [15 ddd overlain present 7
90051138N 82w 125 ddc ‘ overlain r .resent

     

 

 

 

 

Table 3 (cont’d).

 
 
 

115

 

 

overlain

—W Glacial De 08's
III-m—

l
4761 138NT84w 27 ccc

absent

    

 

4762 85W 26 odd

46491138N|86W 11 acc

 

 

4657 138N 86W 11 ddb

overlain
overlain
overlain
overlain

.l__
|

absent
_prpsent
. resent
. resent

ii

 
     
     

 

      
   

 

 

    

     
  

     

 

13 ccc 1 overlain [gent
4650 138N 86W I14 abc | overlain resent
resent
86W 17 ddc overlain 1 _present
18 dcd overlain . resent
4544 138N 86W 20 bab overlain . present

        
   

   

 

45451138N 86W 20 bbb overlain ' resent
i

4550|138N|86W 35 bbc | overlain present
4543,138N 87W 03 dbb , overlain resent

4766'139N 81w oeaaa

     

 

      

   

 

 

 
    
   
 
   

9326139N 81W 25 cbb | overlain present
9015139N 81w 36 ccd i overlain % present

90121139“! 82W 25 bbd .
4751 '139N 83W 12 dba overlain present
4764i139N 83W 28 dad I overlain + present
4760 139N 84W 27 bbc overlain absent
46431139N 85W 18 dcfir overlain '7 present
4641 139N 85W 18 dcd overlain __j7_ _present
4652l139N 85W 21 bac overlain resent
4653 139N 85W 22 bcb overlain resent

overlain . resent

  
    
 

  
  
 

 

  
 
 
  
    
     
   

   
  
 

  

 

    

 

   

 

 

   
 
 
 
 
  
 

 

   

     
     
 

  
 

   

   

   

 

   

 

   

 

 
    

 

   

4651 1139N [85W 130 aab overlain absent
4659 139N486W 22 ccd L overlain pppsent
46601139NL86W 22 ccd ' overlain present
46487139N 86W 25 ddb L overlain present
4661 139N 86W [27 baa overlain 1 present

   

 

     

4658139Ni§6WJ27 bab overlain present
4655;139N 86W 134 acd J overlain present
4654 j139N L876W 34 adc overlain present
4647.139N 86W 35 bda overlain present

 

 

 

    
 
 
  
 
 
 
    
 
  
    

   
   
  
 
     
    
  
  
  
 

 

 

 

 

 

 

 

 

l 1
present
1
present
,

.1

l

l

4644 139Nl86W ,35 cbc overlain l
1 present

I

4756139N 87w 23 bbb overlain ,l
7 9298 139N188W 08 ccc overlain 1 present

|

l

l

l

 

4645r139N 86W 1'35 ccc j overlain
4755 139N 87W 16 cdb l overlain present
7 4 present
79331p139N l88W 106 ddd overlain

4540‘139N188W 15 ccc i overlain present 7 7

 

 

 

 

 

4541p139Ni88Wfi25 bad i overlain present
74539 139N 88W 128 dda 1 overlain present
4538 139N 88W 31 bbc overlain present

 

 

139N [88W ‘34 bcc l resent

4753 overlain

           

 

 

 

 

116
Table 3 (cont’d).

—W Glacial DeoslS
mum——

--
4535 139N 89W 08 ddc overlain resent

8956 139N 89W 71728 daa overlain p_re_s_ent
8957 139N 89W {28 dba overlain resent

8961 139N 33 ddd overlain present

9016 140N 81W 06 ccc overlain present

   
   
    

 

    
     
     
      
   
   
    
    
 
     
      
  
 
  

  
     
   
   
   

  
  
    
  
 
   

   
   
   
   
  
    
  
     

 

 

9017 140M 81W 18 abd overlain resent
9327|140N i82W 01 dad overlain resent

     
  
 
  
    

overlain

4765 MON 16 aaa

_present

 

 

 

   
     
   
  
  
  

4759 MON _35 ccc overlain pr_esent
4758l140N 85W 18 bbc I overlain present

 

464ol140N 85w 725 bbc overlain resent
140N 85W £25 bob 1 overlain j present

140N 88W 16 adb1 overlain—j present
4536140Nl89W—'15dcc j overlain l present

4537 140M 89W 136 add overlain‘JI resent
9297 140N 90W 1180bc p overlain_*7

present
4532 140N 90W 21 bbb overlain
140N 90W 21 bcb overlain

 

     

 
   
  

 

  
  

 

  

 

   
 

. resent

    

 

 

 

 

msent
140N 90W 32 bdd overlain present
4533 140N 90W 34 aaa overlain resent

          

 

 

117
Appendix B. Hydrogeologic data.

Table 4. Water-level data for the Fox Hills aquifer.

   
   
 

Water Elevation
mm

Hettin 2 er 8- Stark counties
132N 091W 28000 2179 664.2
091W 11000 2082 634.6

Mercer & Oliver counties
140N 085W
14m 1ch
141N 089W 20GB
09 C
0908
141N 090W 19CCD 2076 632.8

 
   
 

 

      

  

GI
01
701
U

N-fi
on
mag
8c»
to?
ink!

or
N
.‘9 .
l

7
204

  
  
   

.5
E
Z
a:
E
(a)

   

 

 

Grant & Sioux counties

129N 080W 23000 1859 566.6
129N 081W . OlBAB 1778 541.9
129N 087W 1 10880 1975 602.0

130N 082W 36880 1878 572.4
130N 083W _lfifl 553.2

130N 084W 36AM 1900 579.1
130N 085W 170M 1888 575.5

a
16000 1783 543.5
30AM 2073 631.9
132N 160M 1827 556.9

133N 080W 13DDA 1674 510.2

133N 080W 310001 1703 EE-
133N ,_oaaw [12A0A1j:1765 j 538.0

   

 

     
    
 

 

 
 
     

08
08

g;

   

     
 

  

 

133N pasw 12AAO 1837 559.9
134N_I 082W 36000 1677 511.1
134N 085W |218ABtj 1923 586.1
135N l 090w l2386l31 1 637.3
137N l‘oetiw 21000 605.3

Morton Cou

135N 079w 10AAB1
135N 063w 320881
136N io79w osccc
136N 081W 070001 _, 1760 . 536.4
136N 1081w 16000 L 1766 538.3
136N 082W 070001 1778 541.9
137N 083W 060001 1774 540.7
137N [986w 03AA01 T 1868 569.4
138N ioa1w 09.481317 1699 1 517.9
139N ‘081W 0480A2 1738 ‘ 529.7
139N 1081w 109491741 1739 L 529.7
139N 083W 12DBA1 l 1776 (
139N 088W 348001 1962L
140N joesw 103000
140N 090w 117ACB
140N 090w 2008.41

 

 

  

  
  
 

  
   
 
  

 

      

 

 

 

 

 

      
 

 

   

 

   

 

 

   

.sze_a_—..

 

 

   

 

       

 

   

 

 

    
  

  
  
   
   

 

.l__.._.

 

 

1822 1
2034 1
2095

 

 
  
   

 

 

         

118

new
mom
mom
nor.
«on
com
mmv
0m¢
«av
«on
mom
«on
n.3,
mfln
Nfln
own
nmn
mnn
nvn
men
000
000

Nfln
«cm
000
new
con
Gov
00¢
0m?
wmv
don
won
000
«Hm
ban
NNn
run
«50
ovm
0vn
mmm.
O00
n00

Nfim
0H0
hon
mom
Hon
00v
00v
now
now
N00
«60
hon
«Hm
0.20.
«an
0N0
vnn
own
hem
0mm.
#00
00n

0am
mam
04.0
won
000
non
non
von
non
mon
000
000
Nan
ban
nun
awn
vnm
ovm
nvm
000
#00
>00

0H0
man
man
«an
Nam
nan
VHO
an
Nam
0H0
mom
can
nHm
01-.
34.0
onm
0mm
flvn
nvn
own
.30
000

NNn
0H0
0H0
ham
mfim
nNm
5N0
an
man
man
Nfim
Hflm
0."...
Hum
0N0
nnm
mnm
mvm
own
000
N00
000

ram
awn
mam
«N0
mun
Hnn
mnn
nnn
0N0
0N0
van
Nam
an
nun
awn
nnn
an
N00
900
000
000
M00.

onn
0N0
mum
0N0
own
man
mnn
ban
nnn
6N0
0N0
03.
«N0
awn
nmn
mum
nvn
man
N00
>00
Q00
Ohm

mmm
Nfln
OHM
Hnn
vmn
0mm
va
an
ovn
0mm
«mm
«mm
«mm
nmn
mmn
mvn
02...
«00.
vnm
v00
Ohm
th

ovm
hnm
mnm
man
man
«in.
nvm
hem
mvm
own
now:
mvn
Nvm
nvm
own
awn
«mm
000
000
Ohm
fibm
04.0

men
.30
«mm
mnm
ovm
nvn
mvn
mmn
000
bur.
N00
000
mvn
onn
nmn
0mm
H00.
000
rpm
050
firm
can

nvn
:0
fivm
«#0
:0
mvn
#00
000
N00
N00
000
000
000
90.0
man
N00
000
Nhn
>50
«mm
H00
N00

mvm
mvm
mvm
men
0mm
mmn
com
000
Q00
«00
«.00.
00m
000
M00
000
000
Ohm
nhm
2.0
H00
n00
000

v0.0
«00
38:0
nmn
«.00
H0m
000
2.0
050
ohm
mp0
2.0
mwm
050
«ha
Mbn
chm
mhm
ohm
man
«mm
man

500
man
000
«00
non
000
th
hbm
N00
000
ram
mom
arm
mp0
2.0
mhn
2.0
000
N00
000
Nmm
ram

00m
00m
000
000
awn
vrm
mhm
mom
hmn
Hum
.30
men
«.00
0mm
nun
mom
0.00
000
bmm
Nam
#00
N00

nbn
firm
mum
firm
0hm
own
van
mmn
Nam
nan
0mm
0mm
van
mam
nan
mam
nan
cam
man
man
«00
mo0

000
omm
own
awn
cam
#0....
Hum
nan
man
000
N00
N00
H00
H00
H00
H00
H00
mam
now
000
Ha0
0H0

000
hmm
mmm
awn
Nmn
man
man
H00
v00
«.00
000
000
mo0
a00
«00
moo
0H0
Nfi0
nd0
0H0
0N0
MNO

0mm
vmm
mam
ban
mom
N00
000
000
.20
ma0
mfiu
0H0
0H0
hH0
haw
ha0
0H0
«N0
0N0
0N0
on0
NMO

m00
m00
v00
000
>00
0H0
mam
0fi0
ma0
HNO
NNO
VNO
0N0
0N0
0N0
0N0
0N0
on0
mM0
000
mn0
ov0

nH0
NHO
MHO
VHO
0d0
0H0
HNO
VNO
0N0
m~0
OM0
NMO
MMO
vm0
MMO
MMO
vm0
mm0
«v0
0V0
hv0
wv0

NNO
.nN0
HNO
NNO
0N0
5N0
«N0
Nm0
WMO
>M0
mm0
OV0
Hv0
Mw0
mvw
mv0
:0
bv0
000
mmo
mm0
000

mm0
mN0
mN0
.nM0
nmw
mn0
mm0
ov0
M¢0
mv0
hvm
mv0
000
N00
mn0
mn0
mn0
000
>00
96.0
000
H00

0M0
nm0
5mm”
mm0
H00
«50
0V0
mv0
H00
mm0
000
500
mm0
H00
v00
N00
H00
N00
M00
000
>00
m00

 

mfl0
.20
vv0
0V0
¢v0
«n0
«m0
000
000
000
N00
v00
000
000
m00
m00
m00
000
Q00
:0
Mb0
0>0

.AEV amE 657563 E0: Emu _m>m_¢9m>>

.Lotscm m___I xou 9: E m_m>m_ 50m; ”.0 cozmSEB Le Emu SQE .m 058.

119

0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0

0.0
0.0
0.0
0.0
0.0
0.0
0.0
H.0
0.0

0.0
0.0
0.0
0.0
0.0
0.0
m.nH
n.NH
0.0
0.0
h.0
«.0
H.n
v.0
0.0
h.v
0.0
0.0
v.H
h.h

0.0
0.0
0.0
0.0
0.0
0.0
m.mH
n.nfi
v.md
0.0
n.m
0.v
v.0
h.h
m.h
v.v
0.0
«.0
0.n

0.0
0.0
0.0
0.0
0.0
0.0“
n.0H
0.0H
n.0d
”.mH
h.HH
#.0H
fl.HH
0.0H
«.5
N.N
H.N
n.v
0.0

 

0.0

0.0

F.0N
N.HN
n.0N
0.0a
h.mH
0.0m
0.NN
N.aa
m.nd
m.vH
5.06
m.flfi
n.0H
m.h

0.5

n.0H
0.nfl

0.0fi n.Na 0.nH
H.NH n.va «.mfl v.0H
v.0fi 0.HH H.nH 0.0a b.nH v.0fi

0.NH
n.0H
H.VN
0.nN
n.dN
0.0H
«.0fi
0.0H
0.0a
0.0a
0.bfl
n.0H
N.0H
0.0H
b.0H
0.VH
N.VH
0.0a
0.0H
0.0a
m.hH
b.0H

0.0a
v.mfi
m.mN
0.flN
0.0m
0.0H
H.5H
b.0H
n.0H
«.0H
H.0H
n.0H
fi.hfi
h.hH
n.0a
0.0a
n.0H
0.0H
0.6a
H.hd
0.0a
N.0fl

0.0H
0.0a
n.HN
r.fiN
h.ma
n.0H
d.VH
h.MH
N.nd
N.nH
N.VH
m.mH
v.5H
0.0H
0.0N
0.NN
m.flN
H.0fi
m.MH
0.nH
«.mfl
0.0a

0.0a
0.0H
v.0N
0.HN
v.0a
N.0H
v.ma
h.HH
fi.OH
0.0

m.NH
0.0H
n.>H
N.mH
0.0N
0.dN
F.0N
H.0H
N.nH
v.VH
m.va
n.0fi

«.mH
h.hd
H.0N
0.dN
N.0N
0.5H
0.wH
v.HH
0.0

v.5

b.HH
0.0a
v.hH
«.mH
N.0N
v.0N
0.0“
H.0H
0.5a
m.nH
n.0d
N.ma

0.nH
o.rH
n.0H
h.HN
0.0N
N.hH
0.vfi
0.NH
N.aH
m.HH
n.MH
n.0d
0.hH
n.0fl
n.0H
0.mH
m.mH
n.5H
0.0H
«.0H
m.mH
«.ma

fi.vH
F.0fi
N.hH
n.0fi
¢.hH
n.0d
m.va
H.0H
N.VH
0.0a
v.hH
”.ma
n.0fl
0.0H
0.5a
H.5fi
b.0H
v.0H
H.0H
0.0H
H.0H
m.vH

«.mH
m.MH
m.¢H
0.0a
m.va
0.1a
m.Vfl
0.0a
n.0fi
b.0H
m.HN
H.0N
N.0H
0.0H
v.0a
0.0d
G.vn
0.mH
H.0H
0.VH
n.7H
v.vH

N.Nfi
H.NH
m.fifi
b.HH
0.NH
0.NH
0.nH
d.mH
o.hH
m.mfl
v.fiN
0.0H
H.bH
m.vH
b.NH
H.NH
n.NH
m.ma
O.VH
o.VH
m.nfi
0.MH

0.aH
m.0H
0.0H
0.0

0.0

m.dH
H.mH
h.vH
0.0H
b.0H
m.mH
m.mH
m.ma
H.Nfl
m.m

0.0

N.0H
0.flH
m.NH
0.nH
o.nH
o.mH

>.HH
o.ad
0.0

0.0

v.0

m.fia
0.Mfi
m.va
0.0H
H.0H
0.0H
v.5a
w.va
n.0H
v.0

«.0

0.0

N.ofl
V.fiH
o.aH
o.Nd
m.NH

m.NH
H.NH
0.fiH
m.HH
H.NH
v.ma
m.VH
0.0H
N.hH
n.0H
b.0fi
m.hH
0.0H
N.Nd
0.0

v.h

0.0

0.0

m.0H
H.flH
V.flfl
0.Ha

0.MH
h.mn
o.va
n.vH
v.nd
N.0H
0.0H
0.hH
v.0n
N.mH
n.0d
N.mH
1.0a
n.0H
m.NH
v.0H
m.m

0.0

«.0fl
n.0H
0.0H
N.HH

m.<H
n.0fi
n.0a
v.hH
0.0H
H.mH
d.ma
0.0H
0.0H
n.0N
0.0N
0.0m
N.0N
0.0H
v.0H
b.Nfi
N.Hfi
v.0H
H.0H
N.0H
n.0H
0.0d

0.0a
0.0H
0.0H
v.md
m.HN
N.HN
0.0N
0.0N
o.fiN
n.HN
0.fiN
m.HN
b.0N
0.0a
0.0H
N.vfi
v.NH
0.HH
H.0H
0.0a
0.0H
0.0H

m.0fi
h.hH
m.0a
H.0N
N.HN
0.dN
h.HN
>.fl~
w.flN
o.NN
N.NN
m.NN
0.0N
N.ma
a.bfl
H.0H
N.MH
h.ad
m.0fi
N.0H
0.0H
0.0H

v.5fl
«.md
«.mH
N.ON
o.HN
v.flN
0.NN
0.NN
a.NN
N.NN
N.NN
0.HN
b.0N
N.mH
v.hfi
h.mH
0.VH
m.Na
v.HH
0.0H
m.o«
m.0H

h.hH
0.0a
m.mfi
H.0N
b.0N
H.HN
0.NN
0.NN
a.NN
H.NN
m.flN
m.aN
m.0N
H.0H
0.bH
fi.0H
0.vH
n.mH
v.NH
m.HH
m.fifl
n.HH

0.5a
0.0a
H.mH
0.0a
n.0N
0.HN
m.HN
O.NN
0.NN
m.fiN
¢.HN
m.0N
0.0N
0.0a
0.5«
v.0H
N.mfl
0.0a
O.MH
m.NH
N.NH
O.NH

0.PH
0.0H
m.mH
«.mfl
0.mH
v.HN
h.fiN
m.HN
m.HN
0.HN
O.HN
0.0N
m.mH
0.0fi
h.hfi
0.0H
0.0a
b.VH
0.MH
N.MH
0.Na
0.NH

.AENEV qu 33628800 80: mm2m> b..>_mm_.Emcm:.

.8583 m 853

120

000000

ONflH
ONNN
ONNH
ONflH
ONHH
ONHd
ONNH
ONNH
ONflfi
ounfl
0

o

ONMH
ONMH 0

ouud o

ONNH ONfiH owfld

OOOOOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOOO

 

o ONNH ONMH ONMH ONflH ONNa ONNH CNN“ ONHH ouua ONHH ONHH ONNH ONHH ONNH ONMH ONNH ONWH ONNH ONMH ONNH
c ONHfl o o 0 0 o o 0 0 0 0 0 o o 0 o o 0 0 ONNH
ONMfi 0 0 ONMH
ONMH 0 ONMH
ONNfl ONMa
ONNH
ONNH
ONMH
ONNH
ONMfl
ONMH
ONMH
ommfi
ONflH
ONMH
omwa
ONMH
ONNH

000000
N
M
H
O

OOOOOOOOOOOOOOOOO
0000000000

0
N
N
N

ONMH
O ONNfl
0 0 ONNH
o 0 0 0 0 0 o 0 0 0 0 o o 0 0 o o 0 o O 0 O 0NN«
ONNH ONNH ONNH ONNa ONHH ONHH ONNH ONNH ONMd ONHH ONHH ONMH ONMH ONNd ONMa ommfl ONNH ONNH ONNH ONNH 0mm“ ONMH ONNfi

O

O
OOOOOOOOOOOOOOOOOO

000000000000000
000000000000000
OOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOODOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOCOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO
OOOOOOOOOOOOOOOOOO

.38 085-059.? 0 o 53:82 nmmcfimntomma 0cm 0 omm C mm:_m> 32655

.8883 m 280

Table 5 (cont’d).

Discharge from the Fox Hills aquifer (mm/yr).

-.5

-.5

121

 

122

 

           

8.0 00+ 0000000FHP0N00FES000
03403100.? 0.01.0

     

 

 

                

 

 

 

 

                                   

     

 

 

 

 

 

 

   

 

 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ll 3.: 00.0 8.0 00
$0 H9 0. F0 NF 0.01.0 00. 0F 000 00.0 00 F.
F00. 0N. F_0N,FF-.00.0 00.: 00.0 ENN 1F..F 1 .
3.0 :0 00.NF 8.0 0N.0N 00.0 5.0 00F 0..N 13029
211.|0 00.0 1000 0FNF1000 00.: 00.0 00.0 0N .F.F1 (0810.
a 8.0 0 F00 0F NlNl|.0l 00.0L0N. 00 NF 00.0 00.FN 00.0 Cb 0.0 mwF- F802
Efivom EiNfio 00.013.F 00...F_NONF 3.0 N0.0F0N.010F.0 NF
ago 00 00.0 0F0_00. NF .000 00 0F1N0.0.FF.0 F
I: I: 0N 0.00 0.. 00.0 8.841 3.0 20
E0 0.2. 00.0 00.0 N0.FN 0F. 0 F00 . . F0818
i0.0 0N.0N 38 00.10089 00.01000 . ,. . . .0000N1
amigo: N00 00.0N 0F. 01 NF.0 . . . . . . . <00.FN
figs; 00.0. R0 0F.FF. 00.0.0N0F FN.0 00.0 1 . . . <<<wN
EEFS 00. 0102.0 N0. ...F. 00.0 8.2 NF.0 0F.0 . . m 1803
Emma-00.0 3.0 0N0 00.0 00. 0F 00.0 2.8 2.0g . . . _ 000.3
EE N00 £0 00.0 00.0 N00 .00 3.2 00.0 00.0 . .
EESF 00.0 00.0 0.N0 Nvl01F 00.0 0N.NN 0N.01Fm.0
EENH 00.0 0N0 0. 0111F. FF 3.0 03000.0 :0
MHI§0NJ01 N00 F1010 000 00.: 00.10 3.: 00.0 20
i F0.0N 00.0 0101.0 0N0 B. FF .000 2.: 8.0 :0
IFO. 0N 20 N00 03 00.0 0N. FF .000 00.: 80000.0
“RIF F.F.N saga; 00.0 3.0 00.0 00'. FF 00.0 8.2 0N0 00.0
IN; Emu-E000 3F 0F..F 00.0 0012 00.0 30F 00.0 :0 . . . 3.000:
Egan 00.N 00F 00.0 312 00.0 0.0.: 9.0 :0 . . . .3000:
EESN 00F 0F..N 00.0 00.NF 00.0 9.: 00.0 NF.0 . . . 1 00.02
Egog 3.0 _F.F.0 00.0 N0.F.I11F 00.0 2.8 2.0 NF.0 . . .. . Ko.<0F
GENE—EH 00.0 _30 00.0 000111.000 00.2 00.0 FN.0 .0.0F . . . . . 1000NF
aggigm 00F 00.N BF 00.NF 00I0JN0F N00 0N0 00 . . . 08.3.
Inlll - 1.
I I'll

 

 

 

 

 

 

 

 

 

 

 

 

30.1 ._.

 

mEo_u>_:.o_=__>_ E330. .35 .o. 2:22;... 0:52 E 5.555050

.55 3. 2:81.52 5 :EEEoocou

.5233 051 x0“. 9: 02 San $280693: .0 9an

Emu _mo_Emcoowmo0U>I .0 30:890.

 

123

  

SEE? 0F0 0.00 00 N01
gal 00.0 “00 0|.00 30 00.0
a“: mun-N 00 0&0; 000

FON0 F.N.N N00 30 0.00 30 00.0
.000 X: 00 0.0M1F0N.F 000 No.0 w1F.101 1000110100N 1W100
Emu-0001103 F..N0 FNO N00 00.0 00.0 00.0 FN.0 0.00 00.0F1 1010.0

3.0 00.01 010.0 0101|1.0F.

0|101H01 000 2.2 3.0
+1.00..0F00000

00.0 00 0F

     
   

00.0 NNF 0| FN 10...: NF NF0 10011010 ..oooNN0. F500 20:
000 00F F.F. 0 00: 0.F 000 0.0 0.F 058 2000 03

..III l 411 Ill

00 F0N 0F. 0 00: 0010001. 00 01.N 1<<00F 200m. 203

1. IJ A11l

9.0 30 On 0_. 005 ON N00 00110N110mowo .530 2031

00 0 000F -..10NN F00 .1010.F. 00: 2000 201F..1F
FF N 00NF1110 3000

 

             
                     

 

01 .1 II.

M 1 -
0 0. N1 00.000 |2F08 R013
0

         

   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                               

 

 

 

0F..NF 00.0 0.00 F1N1b 0.00 8.0 30 N00 00.10 001.10 10101.0N11 00.0 0| ..... 1011111002 110101002 .1F.-1011N. .000N0 2000 0:
3.2 E00 00 0.00 0010 000 00.0 0N0 0N0 N1.00F113. 0.F 1011100: 0..F1.000.0_F111F1..N 0080;208:003
NO0N 00.0 3.0 FN.0 0.00 000 R01- . . 100.0 00. 0N 00 0 000F .0.N 00010.F F.0 (08012000 203
2.3 00.0 0.00 2.0 0.00 30 E1 - 0 1. 3:1 0HF 3N.F0|..N..N10<00N E08120:
FF..FN 00.0 0.00 E000 00.0 00.0 000100.10 001101.01F..01F Bl p . 00: 0.3130 m1F 1F.1.0 F1110000N 30001203
E000 E000 000010.00 00.0 3.0 F0.N 00.N 0010101010? 091 F.F .40FFF10F 0F0.N0 .N1 .923. 2,000 203
EFNO E000 2.0 0.00 00.0 2.0. 3.0 00.F 00.0 0h0N 010. 0 0%F 030001 N .N1.0 <<<F.F 30001203
I000 N. 0.00 FN.0 0.00 30 00.0 .F. 80 00.0 00.2 0.0 MN 00: 0.F «0017.01.00 No.82 2,000 203
E80 00.0 0.F0 FN.0 0.00 01? N00 00.N L00.010101.0N 021 0 1 000F 10.N 000 F1 .F....0. 01<O1NF 300Fm12013
0.00N F00 00.0 010010|F0 F00 0N0 0F.0 - mm 0100 .01 010. mm. 10.01101 00: 10F 000.0.001F0N0<mF1.01>>30120F.F
F0.0N 2.0 00.0 0.00 80 F.00 00 010101- 301.30 00.01 1010le 10011101 ..00N.F 00.000100 .101N 000001.. 500120.31

00.3 00.0. 0110|0 F..F0 0N0 F00 0N0 0F.0 . 3.2 00.0 0 ..0 8: 0.1F 0N0 0.0 N 00000 20010 200.311

 

1
1
|

i

 

1..1FI1 . 0 I... 111 1111 2

 

 

 

 

 

 

 

 

 

 

   

 

F0 2 F00- 00.011100011NM01H0101000 01010 1 8. ...FN 10001011100 00.0100 10.001 1.000091303mpk@m
0 .0F 00.0 00.10 0.0 .N1m0 0.00 F00 .1000 :11. 10F -0 110000110010. N00 N0 100 1010000 1330 1210000
00 FN 00.0 00.0 E F|N0 Mg 3.0 9.0 1101.1011110011110MFF100060070101 10181000300000:
5.: FNW1000 0.3 100001000 00.0 000 10011.01 1000+ -1F1.0 000100.100- unnKDNlNEmgbmwF.
00.0N 00.0 1NN|F1.J.1|-.0M0|mM01|NN0N.00 F0 0 100 00: N10010 00.1.01- 1 000.1010 3.010.201?
00.2 mm; 140.011.0120 90 0.00 F0.N 03 10.01112 1.000101 0.F 30100110001..10000N11>>F00.zN1F...F1
E008 00.0 0.0010000 0.00101F.F .F0.F. 00N 1.101 1.00 1.10.0000 0.0 NN 0000N 2000 E:

1 40001010101310: 3130.058 00.0.00.

 

I 1.11. 1 11 .11.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

30 F000 .Ir 3. 1:00 10F L000 0.00900 .1010 1110000N4 E081 2N10F
0F.0 N0.0N 1 00N 00.110100 1F. .00. 00101.0 10000030212100
E0000 1 00N1 0m -1N.001- F.F F300F10N 1.300.008.2000-
E0000 0.0N 13110001 .F 1.180101010th 01010.0: 2.31.. .zN101F.
Emmw. 0N0 00 .001F1 0 1000 1101.500... NF 1F1+ 00.0100. 208 170N001
00.0 0|0. 0|F 1.1-.100F 101111000111 1.011me 3101.101 1Fbflw0p130100..z.N10.F.
F.N.0 F|0 00 .00F 0 1:00.01 00.0103 0F 1N101 10100130131000.21F10F.
E30401! 00 111F001. 10 100.100.3100. 10F. 1.2000. 209 0:10..
mun-001% . NF.N..MF. 1.0100 W.F.00F.| N0..0.F 0000.0 309 32
E00. 0N. 00N 00 1000 11. 03.00.101.001 .boKmWKME. EMF.
EIFNS 000 0N0 _|0.0 F0 800: 30oF zF0F

 

 

 

 

 

 

 

 

 

 

 

 

0o E
03.4 00. 0:00... ____.>. c. cofibcoucou %

  
 

25.023.00.52 E8000. .23 0o . 35.02:. 05.5. c. cozubcoucoo

.8083 0 0.000

 

124

 

 

 

 

                                               

 

 

 

 

     

 

 

        

 

 

 

 

 

 

 

 

 

 

I0I0 0.00 00 0.00 00N .0-N11- 000. 1.0-01.00011011010111 bmmmF10001§b0wF1
E0! .0N 0F. .01u0l01I10 2.0 0.00 N0110 . . . . . . . . 00N .00. 000111: 000100101N01000F1.10>N0F1.-200-F1
E00800? 0.00 10N0 000 0011.0 . . . . . . 0FN LM0110.00110.F 0F010111N.F 1-000000 SN01F1200-F1
HflIOFON N0.0 P00 NNO N00 F00 . . . . . . 10NN 00 000-1. 0.F 0N.0 0101100 (0000_->>N01F_200F

N0. 00 NN.0 0.F0 NF.0 0.00 F0.|0 FN 00N 00N 1-0F0 0.0.0N0 0.101100 <000N 120911700100
F0.” 00 F0 80 N00 00.0 00 00N1-.01011000110310001? 1<<00F0>>001F1 200F-
00.0 00.0|N 0.F0 2.0 0.100 0N0 0N 0FN1FNFN 000 1001000 0.011N.F1 -8000. 2FN10F112m0.F1
00.N 00. 0|0 F0101 F00 0F 000 FN1.000 0F 000.1F.F1.01.0 0030:0081 20101F
00.0 0|N. N0 00b 00101.P F0 .00N 100 -10N0 LC 1000 00.0010. 0<0NF >>00F1.200F
0F.F 0I0. 0N 0.00 0m00 00 00N 1F0 .000 0.F.0N000FH001100009 >>N0F.120.0F1
IF0NI111F 0.0m1 0F 01F11N-01-110100-11F00100010-.111101.01 101000010. 0008-1201010
it. 0N mgII 0N 100: . N0 10001- .111.F 000100 1010- 010000. 10>.F0F12010F
300$ F.00l 0F .10: F0. 00011100 90101.0 10F 1<-oo0N11>>F0F1-12-010F
"FIN100I1-0|00 0N 000 N0 -000-0 -0.-010000 101.0 -.000NF, F509 001010.0-

00.0N110.00 . . 010 000.3 209 202

 

 

 

|
I
1
I
I

+1 I. II. | 1|

00v 0.0 01.0 mo<0N >>mo_. 20010-

N
N
O
N
N
3
C)
('7
'0
I
«3|
10— v—J
O
0
v
ID
40

fi0ll00IN F00 0|.INW1 0N.01F.00

 

 

 

   

 

 

 

 

 

00.N 00.0N 00.0 0.00 0N0 0.00 0F 0NN FF..1L0N0 “10180000110011 1003001002120?
00.0 00.0N 20 01.00 0N0 F.00 NN .0NN .00 -1000 .0F 0010 0.0 N.F 00901202 200F
N0.0 N00N 00.0IN.00 0N0 0.00 0N 0NN F0 000 .0.L0F0F010.1-010-1 0002120012021
N0.0F 8.3 00.0 WM 2.0 0.00 00 00F 0010000 0.F 0N0F .F1.N 118021 ENS-201001
00.0 00.0N 00.0|.0.00 0N0 0.00 . 0N 0NN FF. 0: 1.0.3000 0010013FF-1>>N0F.1200F

0
00%NN100 0N00 0.0 000 0.0 0101-6099308 200F

11|1I11|1|I|1|1 l I III . 1.11

0F 00N10NN 1000 N.Lo0m-.N111F.N1 0000Fr§3F12010F
001F100 000 NN0 Q0 000 0. F.N1<<00F.1>>00F2010F

III 01

F
00 0NN 00N .0: 0.F10N0 0.F 0N 1010101001280 2012

000 0.0 .01.F (4081.1 F508. 2.010F-
000F0N10F $0000 E09 202
000 0.N F0 F00100N §3F 202

001.0 0.0 0N (<03 309120100

ESFN 00.0F N001 00.0 N00
@009 00.0 F||0.01-0F.0 F00
0N.0N 00.I0 . 0|.0110 1.000 .

F0 0|N

0MI00. 0N

 

 

 

  

 

V0—

202 00 00|0

I
|
4
luv. m‘oq‘m.

 

0160-1040010
0
f0
10
.1—
m

 

 

 

 

 

 

«>0 mngNrs

“.N. “Z".

00— oocov'
..

 

 

 

 

 

 

mm 000 lrm 1. 1 |1._.F. Nmo1<0F 0303 1209

0N1 0100 m 000 0.0-1101.0 UO1IOOn 2.69 2000

- F0 110F0110 800001 01F 1 00001 200 0120100

on 000 1N. .100010N1F10N 1(100Nm 2600 209

N00 N0 H7001 F 000 0.F UN 0008 3000 .209

I 000 0425;020:300 ago—1w d mmc__1__m| $0.3) 1:001:00
I 111- 0111 -11.

1 0 1.00311. 1w1.m|000 m.©1101..w1100<mm 2,0001 1Zm1F0F.

 

 

0. N (00.00 12010.01

 

 

 

 

 

 

050001

        

0.0

 

 

 

 

 

 

 

 

 

 

 

00:20:: . 05:2 «coo-Fem 023 E. 35.02:. 0:52 .0 co_§0coucoo

 

._23 0o. wEEF _____2 E cozabcuucou

.6083 0 0.000

125

 

 

 

     

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  

_ «£2. :80 c300. 253.22
I - - - 1 - .. J --.F -..-.- -.-J

38 2.0. 34. 3° N3 MmmmFFm@MFWBWEMFHN. -.«mmwpmemmmmfi
NNFN B...” mmN LF...FN...F.WN.o 08 ..F.N.-.08r-w..w-omm .m...F mm <83 2E3 2m?
3.2 93 .mvN 51% Rd 3.8 F: onF MN 3 o..F._rmN- E3950 .fimIF
.I-I._ll|. ._.. - -.-- 4.59. ..mmmhb mozcsoo {Sakai—Ego:
mflmewflgm : . , . - .-.”.3 meH-MHW3d...HmFM ....mmmmNiflNdmemFyF.
Emma 93 3.-.m%1-N.lole.p:.owF .wolowm- ENOFEHF
EEWQVZ 1.8 ..mNm .NF 03.3 3 .FommFPwN 38F 23F.
SNF a; 8.” MN” mom -.-.F-.o$.m.o-mw.F m2: EmLo 23F.
m3 oIFdN N3. .8 3m .0F 8F. mo 3 933. EmoLF 23F
3.0 8.3 8.0 .NF. 0mm m.F-.omF..m.-..FN.-.N o<<me>FNoFE$F
3.0 g 8e ..GN .03 .3 SF. No Me 859 >>N.oF 28F
NN.o Flap 3.3 0N.- 08F --.N Em C -.th .momvlo->>NoszNvF
E38 3% FFF. ..DNm -.m. 108 met; (moon 3:: 2N3
a; NF...FN 3N .NF. 103---.N on-N..o 0.F 5053;20:2er
ENQFN a: .N.v :02 o .03 m6 .FNN: .momFNisFoF 2F:
amok 8.0 o loam.--.N..-.JoSLo--..o-- mga. ZFoF szF
NS 8.2 Nam .03 -moF. ..F-N .on.F.F mF A033 252 zwi.
8. an 8N .mF 9%. BF 081.3. ...: 38mm..- 38F 23F
oFlmm 3 3+ on HmNF--W.m-.Rm MF: m.F- F088. 38F 23F
oF.m EN». 03 .3 swimmmF 8me FN. -WmfimmeamoFfizO:
mm.» 3.3 8.3 NN 93--.: no .N . 10%? 33: 28F
EB. Nn 8F. 8.1.08 H. F ..GF --mo<N.F. 33F, zowF
3 3 “NW . on.-. o: . 1 INN. ..F...N.- . oooNo 38F. 28F
MM.” Flo. .oIN mg 3 am...“ 00.NF -9R3. FsNoF. 28:
m3 03F a; 8102.... no .N.F Fmo<NN.F>>moF..zONF
fiolm. FN .9413 .8 - 02.... a. no .mN -.<o$NH.->>NoF. .20.:
m2. ..NN .08 -_I. .m.F.-.N..m mmmoN, 38F 23F
on o: o. .N.- -ooéN_ ENE we:
on 08.- 3.0%; .aoqNN. ENE. 20.:
mm 8.3 . 3F .F.o-. .omoNN >>NoF zme
..... 3.1.20 fimN 8b? >>N.o.F -.zpF...F
8 .93 N3 .NF (oo.oF_>>NoF.zSF
.R .08- S 3. 8.0.09 ENE 29.:
.F.....o mF 2.03 52-2.06.
Fm . .F 28m 269 203

8m m . F

 

 

 

 

 

 

 

 

 

 

 

 

 

   

2:253: . o_==>_ «canton.

 

.23 .6. 35323.25: 5 coFEEoucoo

 

3:... ._o. mEE.==E E cozubcoucoo

6.603 m 2an

 

 

 

126

E80 NN.0 N010
F10.-.0 .000 vl.01lll0
F3. FllNH ..00m. 01N1l0

N0.N0 WP 21F. 08
0N0 00!].0 0.2

mNn 0.mm mFd no.0 3.5

0F.N .F..-$.01 FN.0 00.0 morn

 

 

<0.VN_ >>0|00.-

 

FF.0 NN.0 £in

 

mno _ond 00.0

 

00.0 .000 nnfim

00.0NF F5000.-

«00.0.0 230

nun-FD >>mmol

 

 

93 P00

00. 0 n.2-

 

 

.0100

 

.00 0|:.0N

0.00 nv. 0

 

 

 

.0F N..; F0

NO
NV
00

0.5

(D
O
O

0|0..0 WIS
b|0..0 03

00.0 0 NF

0 0
F 0
0.0-Lg

NJNlo-N-l-l
00.

00.0 0.0x. 3.0 0.00 8.0

$5 8.0

 

:0 03.
«.00 3F

 

 

 

0 F0 0.00 0m.0

0N0 N..-”ME

 

 

 

0 F0 mdm FN.0

 

no
9°.
00

Nos

 

mF.0 0.0I0 nmd

 

 

a)
N

0.3
m.0m

F0.0F 3.0 2.0 0.3.

3.0 mdlo 00.0
FN.0 N00

 

 

 

NF.0 N..0||.0

 

 

0N0 0. 0b

 

00.0.

 

2.0 0.00
3.0 0.00

 

0F.0 0.0M
0F. 01 0.00

III]!

|..0|.wm F.F.0

631:5 ojm
F F F.

 

 

EM
3P

i ('1

 

 

ESP 0F..N N.N0
E30 0F.F 0.F0

to...
mldm
0|.. ma

 

 

«001qu

J

|
|
l

,—

l

Fl,-

 

«0009-3000 --.
.NmoooN, 200: EX

 

 

 

Eco—«3: . 2.52 E02»...

 

 

 

to“ In
'1".

82.3 ESF
<00: -FsNoF

 

 

 

 

 

 

 

 

 

 

 

.33 ._u. 3Co_u>_:.o_=_s_ c. cozflfioocco

N WWW-‘32
FFFF

 

 

 

.65 ._o. «EEFEE c. ceanhcoocoo

 

 

U.m<mF_ >>NoF
(.OomQ 2600

 

6.0080 0 9an

 

 

 

 

127

 

00.? 09.0 N013 8.0 0FNF
. 8.0.2.3 000 . -..B0INF. .

8.0 39 RF --0N0 - . , ----.00 N889 2:00
89 .

58.0 00F . . . . . 00NF-. . . .683 58.

3F 2.30mi . . . 00F. . . . .088 >200

E0000“ 3. . . . . . . . .. . 000- . . .. .6020. 2:00

. . . N0.FN 00.0 . .08 . .

-. 1 . F0./3% F520-
.00SN0F-n FN.0 . . .0FNF- coon-M00 >008 202

F

000 . I..---.--b€lN .- . .. EmoNn 3804 23F
. . m-zbngm- .. bob-3 2E

. . . .0 .0.00 0.F . ... -6013000

03 0F 00: 0 80. . N0<<0F;>0F0

9v ...-i-.. 1...... 4 ..... -1]..|

0n . 0FFF-N.0 000. F-msFoF. 2,03

l-l .IL.

00N 08 .0F 0N0 . . 00.3.00, 03.0w

.-- .- F

8: .W-N .0F0 . m .- 8.0009 2:00

 

 

 

 

 

 

 

 

 

r

00N 0.1.0303 E0 3300... 2:00

...000. ix.” .08 “FF- F0300. 2:00

1-.11l11-_ I WI....4 l-..- .l.‘

000 .0.N 0000 3. ..N.0 33% 2:00

anF _N 000m N.F m.v D<mNFU >>N0

- .-.TIKIAVI IJ II -F....- I .-| ...I- .I...|

00FF “0.F 08 0F 3 «0.03, 332%

..|-vi 1.1. a. -. - . \. ...:

00.: .N “000:3. F0000N. >>N0..

.I .l ... ..|...... l .

02F E .03 0.F. ...2FNO

- -. .F.-: . .-- .l l

“02F ..N . 0030” 3wa

 

 

 

 

 

 

 

 

 

n---fia..c...§§§ga ._ .

|..[|.11 ( .4

 

 

mg..- . ..0F0F . . . . 800N 3000.. 2:;
000 N03. . . .002 -_..“ .. www.8- 300-9
M00 «ma-MN J B02 +N . ..o.m.€F-I>§00, -
00.0fin.0-NJM0.0_FF..0. N0F.,0..F.-. .0F-FF -_ . . 3.. monompgmmoFENF
00.0-.0F.m.N-.N0.0tF...0.00mm-.- 000.F. , . n .. <000N F5000. 0F.
00.0.000N-W0F000N0. F0N-.F.N . . .

00.0-00300.0 0N.0 Swag . . . q (003 2,000, 203

 

--| -.. .......|'.-J- . .- -.

 

 

 

 

0.00000, F550. 20:
00.0 3.3.30 NN.0 3N.0.0 - . - , . .. . w«wN-N....F,.>.00.00.20.-.F..F.

. . +F0.0.FN.EF0..0.2.0 3:3. . .03. F089 23F.
00.0 . . 3.0W0.F.N,0F.0_NF.0 00;N --- . . 002. 2009 23F
20 . . 0N.0 FON N00 0N.0 FNF 0N - . 1,303, Emma-RE
00.0 . . 0N.0 SN 06 . . oooi..>>mmo, 23:.
com m . ._.

35.33.25: «canton. .33 ._0. 35.03:. 05.2 E cofibcvucoo .50.... .0. mEEm =52 E cozfiacuocoo %

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6.0080 0 0.03

128

 

    

     

 

 

    
  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2:203: . 0:52 0:830

 

   

 

 

 

 

 

  

083 ._o. «Eu—azsééi :_ coca-00:34.80

       
 

 

 

 

.55 3. 2:5. 0:02 5 cafitcoucou

 

 

.0-00 00m- ..-! 00.0 .000 0.0 00-0.4...- 0.0.0 .0.-0. 4.440.050.0001:0000.0..000.0.44,.z.000-
40.0-00.040 0200 00 00010 0000000101 00..0.0.400..4000-40-10._0. 0.6.00.0.-.30004-20-0-4
4.00.0. 0.. 00.0. 00.0-4.000400. 4.0.0. 00.00.00-280 20.0.0.

00.0-.00 . 000 .400 40.00.040-00 0400-00-00,...gfl00000-0

...4000. m--- 000 m0-.0-.m- .0809 24000.20?

.0 00 .000 00 -- 4.0.0090. .00 -.0-0000m >000lo4- 200-0

.0 0.0-.00.--. 0. - 4.00 .00 4.0.0 008000-3009 200-0

. . 4000 4.0 ... 4.004004000- 400 .0009. 2.40004 2000

44.00- .0.-- . 4,000.0: 00 020000300. 20.00
. - .00 .000-.400 .4000...0...0.0-0--- 0%000-0>.m00 04.0.00.
00«0-..00.0.-.0.0.-0... 00.0-.0000 04.0 4.000 0.0 000- .0. 4000.-.-..0040mw00000. -..-04.000.40-300. V0040
. . . 00. 04.000. 000 00.0w..-4.0m.4. 04.00.00.400- 400.3000, 24000420.?
04:00 .- .N--4000 .00 4.00.. ..-m«<00->>00.04 20004
0.0.0.0. 4100-4000100.- -0-0-. 0400.00.00.00. 00.0-0.

00.0--04...0.40|-04. NF.0-0 00.000.049.000 204m

000- 4.000 4000.00 0.0 .5800 B000 2000

.000- 0.0. 0 4.00.0. 0.0 0.0 050004-300 4200.0
000 4w 49.0 ad 0N.-0- -<m<om4->>vmo 2000.

- . . 040.00 0.0 -fifirfig 0000-0

0004000 0.0 - 04000000040018.0004 30000-2000

0.00 00m 00.04100 00.-. . .004 000 0.F-0.0.0- .0<-000.. 050.0044 2.000

00.00 0.0.04 00.0. 0.0.-- . ...-.000--400-4000.0m- 000 .0p®0.-.e000%0.0
. -000... 000. -000 4000 00 0.0. 000.00,.20000-20-00-

...i 44. .0-.. - Unmwr «1.060050% mmamsoo EEdezofi

4

..... 40.0 04.4 00000.4, 0. 0 000-000- 4.0...0. 10.000.0-44000000-70000
-400. +0.. 0.000 4.004.000 0.0 .00 090-0-0- 450004-2000

0.0 0- 005000-100 00.N-0.0.0.0 400.04 0.0 .0.-N 00000.4 4.50004 ...203

. ..4000 000. 000 0.0 00 30000 40 40004400 -.0..0 080.00. 1.450.000.4202
00.018.04.980 00.00. 00.0 00.0 00.04.}. 03:00.00 0-. .1000 0. 0 00. 0.400810... 050004- 200.0
00.000.00-000 00.004000 0.0.0 0.00. 0.0 0010000 400 40004400 0.40 .000/000.. 2004.10.00
00.0-0000 00.0 00.00 00.0 00.0 000 .000-4.0. 000-0 4mfl-0IJ44040040M0 .0 . .000-00.4. 2400.04 20.0.0.
I000. 0000.000 00 00 00.0800 00040.0 0.0.- .40000 40.0 4000 00 .0...0. -080: 2400.00.20?
I000. 0.0.00.- ..0.0.0 00. 0.00-0.406 00.0 00.0 0.0.0.0...- .800- 40 0-0. 4000 0..0- 0! 000004 3.0.0.0 2.00.0
00.0 00.0N-€0.00 00 00.04000 00.00400 .0--M800- 0 .4000 000 .00 03000430007004.0000
00.0 4:00.000 00.B4.00.0 00.0 0.0M: - 0-1.0000 0.0 4000.00 .00 “2000.00-30004-2000.
400.04- 00.0.0430 . 00.0000 000 W0. “MN-30000 400-60000 0.0...0.00<000..4,>0.mo0.20-00
coo 8.? mod con-40.0 on: J 44000 0.0 Om «(0000 >>omo 2000

a 30 SUE-00.55:

00.4084 0 04000

129

 

96 8.8 8.0 99.- 9.5 98 m3. 9..N NN.0 5.12980 NONI
. . . 93 _NoNN8 8N..NNN0N 8° 8.N.I mNNNovaNN

II'. .NI IIII.

aII .

IIIIII4 IIIII

IIII II, . II|.II.||

..| .I. .INN. .. IINi I IA! IL..-) .

N

 

3:25;: . o==2 Eoflom

.Namd mmN 0N.:

NNI.oI 0NN mIoKN 000 mp. NN mmonNmOIo omNINoN New

.33 .0. 3:22;: . "._.—:2 c_ cozfiu—Nuwcou

.N.ooom|.N.N .Qoo.oN..IOON.N.NON
.NIIIN.o NN.NN NN..o N3. NmN _mNo. 8.052 8.0NoN

--- NINNNNNMNN 8N NN ..NNIISONN .N.: N
3N 3.0 -8..NI N.N.NN modmNNN NN.NNIN NF.0 em 39. NN “NW9;

..m I .-II... I

va moN NNN...

...IIII. II.IIII.

.. ..I. I ... III. ..I INIIIINIWN...
N N.

3. . 39: N9 ..NN. oINmNN

I1 I .LI.|I.. I. HI! II.

N
B o on. o awdflmolo .Immldm ..oINIoINmNIo. olvm.N.oI.N.iw-. NNowNN. ..NIIN..NImmmNN. . -

IIIIIIII II 1 I...

N..--.SmNmN NNm
oxvoN No 68:

.33 ._o. mEm... ..I____s_ E csfitcmocou

<<<wm.. >>mmom ZomN

Ommom >>Nmo Zom N

..II .I II...I|IIINI.I I

TEES .3353

.00on Ema. ZNNN

..NmmmmN >>omo meN

08% 2,89 2me

80mm... 3mg ZNNIN

IN<mmNN 2,89 3.?
m

 

6963 o 993

 

 

 

130
Appendix D. Isotope data.

Table 7. Isotopic analyses of collected water samples.

  
 

——EEII
—mmm
—_——-
__—_—

      
      

130N 082W 3688C 413.2
_—

-15.08 -116.6
-14.33 -110.3

130N 085W 17DAA
133N O80W 31 0001

 
 

 

 

 

133N 083W 12ADA1
133N 085W -16.14 423.7
I 4262
135N Lossw I32CBB1 45.69 421.2
422.3

   

136N 079W . 05CCC -14.09 -102.6
136N 081W I07DDC1 -15.43 -115.9

138N 081W 09ABB1 -15.03 -116.8
—15.01

   
  

      

 

   

Anal ical Error. 0.2 aer mil O-18‘ 1.0 oer mil D

 

131

new
con
non
non
non
oon
Gav
mmv
mmv
Non
mom
mom
man
can
NNn
mun
mnn
mnm
mvn
mvn
0mm
mmn

«.3
non
man
nor.
con
omv
@av
wmv
can.
Hon
¢om
mom
Nan
ban
NNm
hum
vmn
ovm
own
mmm
con
awn

NHn
can
#00
non
Hon
mmv
omv
hmv
mmv
«or.
van
hon
Han
OHM
NNn
mun
can
Own
hvn
0mm
vwm
mom

oHn
nan
OHm
mom.
can
now.
non
eon
mom
mom
mom
mom
Nan
ban
nun
awn
an
own
mwn
mnm
vwn
hwn

mHn
nHm
nan
NHn
Nam
mun
van
MHn
«am.
can
mom
can
man
man
van
can
unn
va
mvm
onn
Hun
our.

Nun
wnm
me
N..—um
adm
nNn
bun
VNm
man
man
Nam
._...nn
mam
flNn
awn
nnn
anm
mwm
onn
mmm
«on
wwm

hNn
Hum
0..“
Hum
man
«mm
mum
nnn
own
cum
van
Nfln
ham
mum
mNn
mnm
Nvm
Nnm
vom
wum
won
mum

onn
mwm
nun
uum
0mm
mmn
onn
hnn
man
bun
own
man
NNn
mNm
mnn
mmm
nvn
mmm
an
hon
mmm
Ohm

Dmm
Nnm
onm
Hnn
can
mnm
New
Nvm
Ovm
0mm
Nmn
Hnn
Nmn
mnm
mnm
flvn
own
vmm
«mm
«mm
Ohm
me

Own
hmn
nnm
nnn
mnn
Hum
nvm
hvm
avm
uvn
fivn
Nfln
Nvm
Mvm
mvm
mum
vmm
own
nwm
ohm
Mhm
mum

mwn
Hem.
mmm
mmn
Ovm
mvn
awn
nnn
0mm
bwm
Nmm
own
new:
0mm
mnn
own
New
mom
bhn
mhm
bhm
0mm

mvm
vvn
nvn
Nvm
vvm
mfln
vmn
mun
Nun
Nwm
mmn
wmn
nan
hmm
mmn
Nun
mum
th
hhm
Hon
Ham
wmm

mvm
mvm
mvm
mvn
omn
nnn
own
new
mom
mom
bun
can
own
Mwn
mom
mwn
Ohm
firm
hhn
awn
mam
mam.

vmm
vmn
vmm
nnn
bmm
.nmn
con
.nbm
mhm
urn
arm
arm
awn
Ohm
me
nhn
whn
whm
mbn
nwm
mmm
mmm

mmm
mnn
00m
Hon
non
mom
me
hhm
Nam
00m
hmm
mum
mhn
whm
ohm
arm
arm
own
«0“
mom
Nam
ham

Dem
mwn
mom
own
mom
«Rn
ohm
nmn
hmm
«mm
Hon
mom
ban
man
man
man
man
owm
hmn
Nam
ham
Now

mrm
mrn
nth
mrn
urn
own
van
mmm
Nam
man
man
man
¢mn
man
man.
man
man
vmm
mmm
mmm
vow
moo

0mm
can
own
Ham
can
ham
Ham
mmm
man
000
Now
Now
How
How
Now
How
How
now
now
now
.ndw
wfiw

mmn
me
mmm
mmn
Nan
man
man
How
wow
bow
wow
moo
«00
new
«00
now
0.3
Nam
mHo
can
own
mam

mom
vmn
mmm
ham
man
Now
now
mew
Haw
Mao
mam
mac
0.3
5.3
haw
ham
mam
NNw
mNo
mNo
one
wa

mom
mom
«00
wow
how
0H0
Maw
ado
me
NNW
NNm
va
me
me
mum
me
mum
onw
MMm
mmm
mmo
ovu

mam
NHm
man
«a;
0am
mam
Hum
«.Nm
wNm
aNo
omw
Nmo
mmm
«no
mmo
mmw
vmo
mmo
vvw
mvw
bvw
mvm

Nun
HNW
HNw
mac
me
5N0
mNo
Nmo
mMo
bmo
mmO
ovu
va
me
mvo
five
vvw
hvm
omo
mmw
mmo
mmo

me
mum
me
Hmw
mmm
mmw
mnw
ovw
fivw
mVo
bvw
mvw
one
mmo
mmw
mnm
mnw
mmw
hme
mmw
owe
awe

vmw
mmw
hnw
mmw
va
vvw
wow
wow
wa
nmw
mnw
hmw
mmo
.nuw
«mo
Nwo
wa
New
Mom
mww
hww
mww

 

won
five
vvw
wvw
mvw
«no
:3
mmw
mmw
own
Now
«we
wow
mum
mmw
mww
mmc
mww
mom
2%
lew
who

.EN 88: 699

.6933 2:: x0“. 9: E mNm>mN $ng No CONNmNJENw ._oN Emu 59: .m 292.

6ch chva0E 052063861 .mN x6593.

132

000000

n.nH
n.NH
m.m
m.m

OOOOOOOOOOOOOOOOOOO

H
D

5.5

00000

o
«.mH
n.WH
v.nH
m.m
n.m
o.v
v.u
h.h
m.h
¢.v
0.0
«.0
o.m

0000

o
m.wH
n.mH
0.0H
m.wfl
m.mH
6.HH
v.0H
H.Ha
m.0H
v.h
N.N
H.N
m.w
o.m

 

o

o
b.0N
N.HN
n.0N
m.md
h.mH
0.0N
w.NN
N.mH
m.mH
n.vH
h.¢fi
m.nH
n.0H
n.h
m.h
n.0a
w.mH

o.o« m.NH m.nH
o.m N.NH m.§H N.ma v.wH
.OH w.HH d.na o.nH h.md «.0a

a.Nfi
n.mfi
H.VN
o.MN
n.HN
m.mH
«.mH
m.aH
m.mH
c.0fi
o.hH
n.wd
N.0H
m.mH
h.vfi
o.va
N.¢fi
o.nH
o.mH
o.ma
n.5fi
5.0H

w.mH
v.mH
m.MN
o.nN
0.0N
m.mH
H.hfi
h.oH
n.0H
N.UH
H.oH
m.wfi
H.5H
h.bH
m.cH
0.0H
M.MH
0.6a
0.6a
H.bH
w.wH
N.0H

m.vd
o.mfl
m.HN
h.HN
h.aH
n.0H
H.VH
h.nH
«.ma
N.nH
N.VH
m.na
v.5a
«.mH
w.ON
w.NN
m.HN
H.wa
«.ma
m.nH
N.MH
u.nH

o.mH
0.0H
v.0N
o.HN
§.mH
N.0H
v.nH
h.Hfl
H.0H
a.m

n.NH
o.mH
n.5fl
N.mH
0.0N
o.flN
b.0N
a.mH
N.mH
v.va
m.VH
m.ma

«.ma
F.FN
d.ON
0.HN
N.ON
O.>H
o.¢H
v.HH
o.m

<.h

h.HH
o.mH
v.hH
N.¢H
N.0N
v.0N
n.mH
H.mfi
0.5H
m.nH
m.md
«.mH

o.mH
0.FH
m.md
h.HN
n.0N
N.hH
0.vH
u.NH
N.aH
n.HH
m.fla
n.0H
0.FH
m.md
m.mH
o.mH
m.mH
n.hfi
m.wa
fi.wH
n.ma
«.mu

n.VN
b.mfl
N.ha
n.mH
m.hH
n.0N
m.va
H.VH
N.VH
m.nH
¢.hfl
n.0H
m.wfl
o.wH
w.hH
H.hH
h.wH
v.wH
d.wH
n.nH
H.mH
m.VH

«.mH
m.MH
m.VH
m.¢H
m.va
m.va
n.vH
o.mfi
n.0H
b.mH
fl.aN
H.0N
«.mH
0.0H
v.mH
a.va
m.vH
o.nH
N.nH
m.vd
n.va
v.vfl

«.NH
H.Nfi
m.Hfi
b.HH
o.NH
Q.Na
0.mH
H.mH
0.5H
m.mH
¢.HN
w.mfi
fl.hH
n.VH
h.NH
fi.NH
m.NH
n.MN
o.eH
o.va
m.nfi
w.MH

w.fifi
m.o«
0.0H
m.m

o.m

m.HH
H.MH
h.va
m.oa
b.0H
m.mH
m.mH
n.mH
H.NH
m.m

m.w

N.OH
m.HH
m.NH
o.ma
o.nH
o.m~

b.HH
o.HH
m.m

m.m

v.m

m.HH
0.0H
n.vs
m.mfi
H.mH
m.mH
v.ha
m.va
n.0fi
v.m

v.w

u.m

N.OH
v.flfl
m.afi
o.NH
m.NH

m.NH
H.NH
w.fiH
m.dH
H.NH
v.MH
m.vH
w.md
N.bH
m.wfl
b.0d
m.hH
m.mH
N.NH
o.m

¢.b

w.m

o.m

n.0H
H.HH
v.HH
m.dH

w.MH
b.nH
o.va
n.vH
v.mH
N.wH
m.ofl
w.bd
v.wH
N.mH
m.mH
N.mH
v.mH
m.ma
m.Nfi
v.0H
m.m

m.m

N.OH
m.oa
m.oa
N.HH

m.VH
n.mH
m.WH
v.5H
$.0H
fl.MH
H.0H
v.mH
w.mH
n.0N
0.0N
w.ON
N.ON
a.mfi
v.na
h.Na
N.~H
v.0H
H.0fi
N.OH
n.0H
a.o«

o.wH
m.wH
o.mH
«.mH
n.HN
N.HN
m.0N
w.ON
o.NN
m.fiN
0.NN
m.HN
5.0N
o.mfi
w.wd
N.VH
¢.NH
o.HH
N.OH
0.0H
v.0H
m.oH

m.wH
F.FH
«.mfl
H.0N
N.HN
0.HN
h.HN
h.HN
m.HN
o.NN
N.NN
m.NN
m.ON
«.ma
«.FH
fi.mH
N.nH
h.Ha
n.0H
N.OH
n.0a
w.OH

v.hH
N.mfi
N.mH
N.ON
o.HN
v.aN
o.NN
o.NN
H.NN
N.NN
N.NN
m.HN
b.0N
N.Md
«.FH
h.mH
O.VN
m.NH
v.HH
a.OH
0.0H
m.oa

>.hfi
u.ma
m.mfi
H.0N
b.0N
H.HN
o.NN
o.NN
H.NN
d.NN
m.HN
m.HN
n.0N
H.mH
w.bd
H.uH
w.va
m.ma
v.Nfl
m.HH
m.«a
m.Hfl

0.FH
w.mH
H.mH
m.mH
m.ON
w.HN
m.NN
O.NN
O.NN
m.flN
v.HN
m.0N
0.0N
o.mH
m.bH
¢.wH
N.ma
o.efl
o.nH
m.Na
«.NH
O.NH

m.hH
n.0H
m.mH
v.¢H
m.mfi
v.HN
h.HN
w.HN
m.HN
w.HN
o.HN
w.ON
m.md
m.mH
F.FH
o.wfi
m.mH
h.Vd
©.MH
N.MH
m.NH
w.NH

.NENEN mm:_m> >NN>NmmNEmcSN

.8953 m 993

Table 8 (cont’d).

O = variable—head cell).

prescribed-head boundary;

ty values (1 E20 =

M

Storat

1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220

1220

0
O
0

1220
1220
1220
1220
1220

0
0
O
0
0

1220

1220
1220
1220
1220
1220
1220

0
0
0

133

0
0
O
0
0
O
0
0
0
O

1220
1220

1220

1220
1220

1220

1220

1220

 

 

 

 

 

Table 8 (cont’d).

Discharge from the Fox Hills aquifer (mm/yr).

134

 

Table 8 (cont’d).

Discharge from the Fox Hills aquifer (mm/yr).

134

135

 

mom
mom
mom
non
Non
can
now
omv
mvn
mvn
mvn
mvn
mvm
mvn
mvm
mvm
nnm
mmm
mvm
mvm.
wmn
chm

Nam
mom
com
non
oom
mmv
omv
one.
mvn
mvn
mvn
ovn
mvm
mvm
men
th
vnm
ovm
uvm
nmn
own
Hum

«an
0.?“
non
non
«on
mmv
omv
fio¢
mov
mvn
mvm
hon
HHm.
man
Nun
mNm
vmm
ovm
bvm
0mm
«um
nun

on
nHm
can
mom
mom
now.
now
won
new
mom
mam
mvn
Nan
ham
nwm
mNm
vmn
ovm
mvm
nmm
vmm
ham

wdm
nfim
NHn
NHn
«an
NHm
van
man
Nam
can
own
mvm
nan
mHm
van
0mm
wmm
Hem
nvn
0mm
awn
com

«NM
0.8
mam
ban
mam.
Mum
hum
vun
mam.
mam
men
new.
man
«Nu
mum
nnm
mmm
mvm
0mm
nnm
Nam
09...

hmn
HNm
mum
awn
mum
Hmm
mmn
nnm
uNm
omm
awn
mvn
ham
MNm
mum
mmm
Nvm
«mm
vow
own
won
mwm

0mm
our.
mun
uNn
onm
mnn
mnm
hnm
nnn
hum
ONn
mvm
avn
own
mmm
mmm
m¢m
nmn
Nwm
hmm
mwm
Ohm

nnm
Nmm
own
«an
me
mmm
«en
New
ovm
wnm
Nmm
Hnm
Nnn
nnm
mmm
nvm
mvn
vmm.
vmn
vow.
Ohm
th

ovn
hnm
mnm
mnm
0mm
.nvm
nvm
bfin
mvm
uvm
nvn
an
Nvm
nvm
own
mvm
vmm
Own
mwm
ohm
firm
urn

flvm
:Vm
mnm
mmm
ovm
mwm
mvm
nmm
0mm
5mm
Nmm
our:
«3...
0mm
nmn
mum
Hem
mum
hbm
afim
rpm
own

mvm
v3...
nvm
Nvm
vvn
mvm.
vmm
mnm
Nwm
Nam.
mmm
wnn
mmn
hnn
mmn
«on
man
th
bbm
Ham
Ham
Nmm

mvm
mvn
awn
mvm
onm
mnm
own
mum
mwm
Gum
bum
Own
com
Mum
mwn
mwm.
Ohm
firm
hhm
Han
man
wmm

vmn
vmn
vmn
mnn
hmm
Hmm
own
firm
nbm
mhn
mhm
firm
mom
Ohm
Nun
fibn
chm
nhn
mhm
mam
awn
mmm

mmn
mmm
own
Hon
Mom
mom
Nhn
hhn
«an
own
hon
mam
mhm
mbm
mhn
mhn
mhm
0mm
Non
won
«an
ban

won
mom
wmm
wan
awn
vrn
whm
nmm
bum
Ham
Nam
man
hmn
won
man
man
mmm
mmm
ham
Nan
ham
New

mhm
firm
firm.
nbm
Ohm
own
van
mmm
Nam
man
0mm
0mm
vmm
man
man
man
man
«an
mmm
mmm
vow
mow

can
can
own
Ham
«.wm
hmm
Ham
nmn
mam
oow
Now
New
How
How
Now
How
Now
new
mom
woo
flaw
mac

mom
ban
0mm
«on
man
mmm
mmm
How
vow
new
mom
«Om
mew
mow
mow
aom
oaw
Nam
mam
0H0
ONw
nwm

mom
van
mam
ham
man
Now
now
mow
Ham
Mao
mflw
mam
wHw
haw
N..;
wa
mam
aNo
mum
me
omm
NMu

new
moo
vow
wow
how
0.3
_35
93
mfiw
HNw
NNm
va
mum
me
mNo
me
wNw
onw
me
0mm
mnw
oww

mam
Nfim
”Hm
vaw
mam
mam
Hum
va
0N0
me
0mm
wa
nnw
vmd
mmm
mummy
one
mmw
vvw
mvw
hvw
mfiw

«No
HNm
HNo
6N0
mwo
>Nw
mNm
wa
mmw
PMo
mmw
ovm
va
mvu
mvw
mvo
vvw
hqw
0mm
mmw
mmw
mmo

va
mum
me
.nmu
mmw
mmw
0mm
0N6
fivw
mvw
hvm
mvw
0mm
Nno
mmw
and
mmw
nmw
5mm
mmw
00w
flow

vmw
mmw
>mw
mnw
fivw
wvw
mvw
mvw
Hmo
mmm
mmo
hmw
mmc
ma
:5
New
.89
Nwm
mom
mww
F00
mmm

mmm
NN.0
vvw
eve
mvw
wa
vmm
wmw
mmw
omw
Nwo
vww
mew
mew
moo
mew
moo
mww
mmw
._..bw
mwo
whm

.95 866: .699

.98 N39,: coNNw_3E_m 9936.2 33 .m 9ka

136

OOOOOOOOOOOOOOOOOOO
In
I“

r1
'0

b.h

00000

O
«.mfl
m.nfi
v.na
n.m
n.n
o.¢
v.0
h.»
m.h
v.v
0.0
H.o
o.n

0000

o
n.mH
n.mH
m.wH
m.mH
m.nfi
h.dH
v.0H
N.Hfl
0.0H
¢.>
N.N
H.N
n.v
o.w

 

o

o
b.0N
N.HN
n.0N
m.mH
h.mH
0.0N
Q.NN
N.¢fi
o.na
n.wn
h.Vfi
m.flH
n.0H
n.h
m.h
n.0H
o.ma

o.oH n.Nfi «.mfi
m.m H.NH n.vH «.mfl 9.0N
.0“ c.Ha H.MH o.nH h.nH v.0d

m.NH
n.mfl
d.VN
o.nN
n.HN
m.mH
«.mfl
n.mH
0.0H
n.0fi
o.hd
n.wH
N.0H
m.ma
h.Vd
O.VH
N.VH
w.mH
o.md
m.mH
n.hfl
h.wa

u.ma
v.ma
m.n~
o.nN
m.ON
n.mH
H.hfi
b.0H
m.uH
N.ua
H.wH
m.wH
H.hfl
F.FH
n.0H
”.mfi
m.mH
o.mH
0.FH
«.FN
0.0a
N.wH

m.vfi
o.mH
m.HN
b.HN
h.nd
n.0H
H.vH
h.nd
N.MH
N.flH
N.vH
o.mfl
v.bH
«.mfi
0.0N
0.NN
m.HN
«.mH
m.nd
m.ma
N.nH
o.m«

o.nH
o.wH
v.0N
O.HN
v.mH
N.ufi
v.nH
h.dH
H.0H
m.o

n.NH
o.mH
n.hH
«.mH
n.0N
0.HN
b.0N
H.ma
«.mH
v.va
m.vd
m.ma

N.na
F.FH
H.0N
w.HN
N.ON
0.F“
o.va
v.HH
m.w

v.5

b.HH
o.nH
<.bH
N.oH
N.ON
v.0N
m.nH
H.mH
o.PH
o.md
n.nH
N.nH

o.nH
o.hH
n.mfi
h.HN
m.ON
N.hH
w.vd
O.Na
N.HH
n.Ha
m.MH
n.0H
m.bH
m.mn
n.mH
o.aH
m.wa
m.ba
n.0a
H.uH
m.mH
N.mH

m.va
h.nfl
N.hH
n.md
m.hH
m.wH
m.va
H.VH
N.VH
m.ma
«.FN
n.wH
n.0fi
o.mH
m.hfi
a.ha
h.oH
v.wH
H.0H
n.ma
a.md
m.VH

N.na
m.ma
m.va
a.va
m.¢H
w.vfi
m.VH
o.nH
m.wfi
h.mH
m.fiN
H.0N
«.mH
v.0d
v.mH
m.va
w.vd
o.mH
H.mfl
m.vfi
n.vH
v.va

«.NH
H.Nfl
m.HH
h.HH
o.Na
m.NH
m.mfi
H.nH
0.FH
m.MH
«.NN
m.mH
H.hH
n.VH
h.NH
H.NN
n.NH
m.nH
o.va
0.0H
m.ma
w.ma

m.HH
0.0H
0.0H
m.m

w.m

n.HH
H.na
b.VH
m.ua
h.mfi
m.mH
0.0“
n.nH
a.Nfi
n.m

m.m

N.OH
0.HH
w.NH
o.nH
o.mH
O.MH

h.fifl
o.Hfi
m.m

m.m

v.m

n.HH
O.MH
m.va
w.wH
H.mH
n.mH
v.5H
m.vH
n.0H
v.n

¢.m

0.0

N.OH
<.HH
m.HH
o.NH
m.NH

m.NH
H.NH
m.flH
m.HH
H.NH
v.mH
n.va
o.mfi
N.hH
n.wH
b.mH
a.bH
a.na
«.NH
0.0

v.n

w.m

w.m

n.0H
H.NH
«.dfi
m.Ha

m.MH
h.MH
o.vH
n.¢a
¢.nH
N.0H
0.0H
0.FH
v.mH
«.mH
m.mH
N.mH
v.mH
m.wH
m.NH
v.0H
m.m

m.m

N.OH
m.OH
m.oa
«.NN

m.va
m.mH
n.wH
v.hH
m.wH
H.md
H.mH
v.md
m.ma
n.0N
0.0N
w.ON
N.ON
m.mH
v.0a
b.NH
N.HH
v.0d
d.oa
N.OH
m.OH
«.0H

0.6a
m.wH
o.mH
¢.mH
m.HN
N.HN
n.0N
0.0N
o.flN
m.fiN
w.aN
n.HN
b.0N
o.mfl
w.WH
N.VH
«.NH
o.HN
fi.OH
0.0H
v.0H
m.0H

m.wa
b.5a
«.mH
6.0N
N.HN
0.NN
h.HN
>.HN
m.HN
O.NN
N.NN
m.NN
m.ON
N.m~
H.5H
H.mH
«.ma
h.HH
m.oH
N.OH
n.0fl
m.OH

v.>H
N.mH
«.mH
N.ON
o.HN
v.HN
O.NN
o.NN
H.NN
N.NN
N.NN
m.HN
b.0N
N.md
¢.bH
h.mfi
0.9H
m.Nfl
v.HH
m.OH
w.OH
m.oa

F.FH
w.mH
m.mH
H.0N
b.0N
H.HN
O.NN
o.NN
a.NN
fl.NN
m.dN
n.HN
n.0N
H.mH
w.bH
H.wd
o.va
m.mH
«.NH
m.NH
m.aH
m.Ha

w.hH
w.ma
H.mH
m.mH
n.0N
m.HN
m.aN
o.NN
O.NN
m.dN
v.HN
m.0N
0.0N
o.ma
w.hfi
v.0a
N.m~
O.VN
o.mH
n.NH
N.NH
O.NH

w.h~
m.mH
m.mH
v.mH
m.mH
v.fiN
b.HN
m.HN
®.fiN
0.HN
o.fiN
0.0N
w.MH
m.ma
F.FH
v.0fl
m.mfl
h.va
w.md
N.MH
m.NH
w.NH

.NUNNEN mm3Nm> @2823me

.6953 m 633

 

 

Table 9 (cont’d).

variable—head cell).

prescribed—head boundary, 0 =

Storativity values (1 E20

1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220 1220

0
0
0
0
0
0
0
0
0
0
0

1220
1220
1220
1220

1220

1220
1220
1220
1220

0
0
0
0
0
0

0 1220
0 1220
0 1220

0
0

0 1220 1220 1220 1220 1220

O 1220 0

O
0

1220
1220
1220

0 1220 1220 1220 1220 1220 1220

O

137

0 1220

O 1220 1220
0

0
0

0
0

1220
1220
1220
1220

0
0
0
0
0
0
0

1220

1220
1220
1220
1220

0

 

 

 

 

 

Table 9 (cont’d).

Discharge from the Fox Hills aquifer (mm/yr).

138

 

139

 

«on
com
mom
non
Non
oon
mme
mmv
mmv
Non
mom
«on
nHm
mHn
Nun
mum
nmn
mnm
mvm
mvm
emn
0mm

Nam
mom
eon
mom
con
Gav
emv
emv
oav
«on
2we“...
mom
Nan
ham
Nun
hNn
vnm
ovn
evm
new
oen
Hem

man
can
how
new
Hon
mmv
eav
hmv
mmv
Non
«on
how
Hfim
eHn
Nun
0N0
«mm
ovm
hem
emm
wen
men

eHm
MHm
One
eon
eon
non
non
vom
new.
mom
eon
mom
«Hm
ban
mNm
own
vnn
own
men
men
ven
her,

man
man
an
Nan
Nam
nan
van
nan
«Hm
can
mom
can
Minn
use
fun
one
one
How
five
one
Hem
een

NNm
mam
eHn
ban
«Hm
mun
rum
VNn
mam
nHm
Ndm
fiHn
nan
HNm
eNn
mnm
mmm
nwm
one
new.
Nen
eem

hum
HNm
man
Hum
mNm
Hnm
one
nmm
fan
can
van
NHm
ham
nun
mun
nnn
New
New
vem
een
eem
men

0mm
eNm
nwn
eNm
one
nnn
wmn
hmn
0mm
hNn
own
eHm
Nun
mun
fine.
mnn
eve
nmn
Nen
hem
men
Ohm

mmn
Nmm
one
Hnn
vmn
one
five
five
own
enn
Nmm
Hnn
Nam
nnn
«me
five
mvn
ver-
vmn
wen
Ohm
an

ovm
«Inn
mnn
mnm
mnm
fivm
mvm
bvm
mvn
eve
five
Nvm
Nvm
nvm
evn
mvn
wen
Oem
men
one
firm
mhm

five
Hem
mmn
one
ovn
nvn
ave.
new
emm
hem
men
one
mvn
0mm
men
enm
Hem
wee
hhm
mhm
hhm
0mm

mvn
vvm
nvn
an
vvm
men
vnm
new
New
New
mmm
enm
new
bum
men
men
een
«be
firm
Hem
Ham
«mm

ave
awn
mvn
mam.
one
new.
oen
men
men
aen
hen
oen
oen
men
men
men
Ohm
an
bbm
Non
mmm
emn

vmm
vnn
vnm
nmn
hmm
Hem
een
fish
firm
are
are
arm
men
Ohm
th
firm
me
mhn
mhm
men
men
men

men
men
oer.
Hem
men
men
Nun
hhm
Nmn
emm
ham
men
are
mbn
are
are
are
own
men
own
«an
ban

eem
ewe.
eem
eem
mem
«be
ohm
mom
bun
Ham
«an
new
hen
ewe
mmm
mmm
mmm
ewm
bee
Nam
ham
Noe

mnm
mnm
mnm.
nhm
ebm
oem
ewe
«en
man
man
emn
ear.
vmn
man.
mmm
man
man
vmm
man
man
voe
moe

own
our.
own
Ham.
vwe
hem
«an
man
man
ooe
Noe
Noe
doe
woe
Hoe
Hoe
.noe
moe
moe
woe
.nHe
eHe

men
new.
men
mam
Nam
man
man
Hoe
voe
hoe
moe
moe
moe
moe
moe
moe
oHe
NHe
mHe
mHe
owe
made

man
vmm
mam
bmn
mam
Noe
moe
woe
Nae
MHe
mHe
efle
efle
bHe
bHe
hHe
mae
HNe
mNe
mNe
ome
Nae

moe
moe
voe
eoe
roe
Ode
mHe
efie
mae
HNe
NNe
vme
mme
nNe
mNe
mNe
eNe
one
mne
mme
mme
owe

Mae
NHe
Mae
VHe
eae
mHe
HNe
VNe
eNe
mNe
one
Nme
mme
«we
mme
mme
vme
mme
five
eee
bve
mwe

NNe
fiNe
HNe
MNe
mNe
hue
mNe
Nme
mme
hme
mme
owe
five
five
Nee
flee
vve
five
one
mme
mme
mme

mNe
mNe
mNe
Hme
mme
mme
mme
ove
five
mve
five
mve
one
«me
fine
fine
mne
mne
bme
mme
oee
Hee

«.Me
mme
hme
mfie
ave
qve
eve
wve
fine
mme
mme
bee
mme
Hee
«Nee
Nee
Hee
Nee
Nee
nee
bee
mee

mMe
.2e
2e
ewe
ave
Nme
vme
eme
wme
oee
Nee
wee
eee
mee
mee
mee
wee
wee
mee
«he
mbe
ere

E 9.8: 692

6me 09286 9: 95603 6.0% 02 mcocm> No 82386 NON Emu SQE .oN 9th

 

 

 

 

 

140

OOOOOOOOOOOOOOOOOOOOOO

OOOOOOO

n.NH
O.Nd
O.NH
o.NH
O.Nfi
o.NN
o.NH
O.NH
o.NH
o

o

o

o.Na
fl.NH

.NH H.nH

OOOOO

m.nH
n.nH
v.MN
O.NH
o.Nd
o.Nfi
O.Nfl
O.NH
O.Nfl
0.Na

o.NH
o.NH
n.vu
o.mH

000°

n.md
n.0H
o.mfi
n.uH
n.ma
O.NH
O.NH
O.NH
o.Nfi
O.Nfi
O.NH
O.Nfl
o.NH
O.NH
m.NH
«.mH
h.nfl

 

o
o

N.HN
n.0N
m.mH
b.mH
e.0N
e.NN
N.nH
e.nd
m.VH
b.¢d
m.MH
o.NH
o.NH
o.NH
o.NH
e.mfl
m.nfi
v.ea
v.eH

m.Na
n.md
H.<N
o.nN
m.HN
m.na
«.md
n.md
n.0fl
e.mH
o.>H
n.eH
N.en
m.na
h.¢d
o.vfl
N.vn
e.nfi
m.mH
m.mH
n.hH
h.eH

e.ma
v.mH
e.m~
o.nN
m.ON
n.mH
H.5fl
h.eH
m.eH
N.eH
H.eH
m.eH
d.hH
h.bH
m.mH
e.mH
m.md
o.mu
e.hH
«.FN
e.ea
N.eH

a.VH
e.OH
n.HN
h.HN
h.oH
m.eH
N.vH
h.MH
N.flfi
N.nH
N.<fi
m.nH
v.hH
m.efi
e.ON
e.NN
m.HN
H.ma
m.nH
m.nH
N.na
e.md

o.nH
0.0H
v.0N
o.HN
v.0H
N.eH
v.MH
h.Hfl
H.0fl
m.m

n.Na
o.nH
m.ha
N.MH
m.ON
e.NN
b.0N
H.MH
N.nd
v.VH
m.va
m.ma

N.nH
F.FN
H.0N
e.fiN
N.ON
0.5“
o.va
v.Ha
0.0

v.b

h.HH
O.nfi
v.hfl
N.mH
N.ON
v.0N
m.mH
H.0H
0.5a
m.ma
m.ma
N.mH

o.na
o.ha
n.aH
b.HN
n.0N
N.bH
e.vfi
e.Nfl
N.dH
m.NH
m.MH
m.eH
0.FH
m.mH
n.mH
o.mH
n.wH
m.hH
m.eH
H.eH
n.nH
«.mH

n.va
h.ma
N.hH
n.ma
m.hH
n.eH
m.va
fl.vH
N.vfi
“.mfi
v.hH
m.wH
n.mH
o.mfi
e.hH
H.bH
h.eH
v.eH
H.efi
n.mH
fl.ma
m.vH

N.NH
o.ma
m.vfl
m.va
m.va
e.¢H
n.VH
o.mH
n.eH
h.mH
n.flN
N.ON
N.mH
e.eH
v.mH
m.va
m.va
o.mH
«.mfi
o.VN
n.va
v.VH

«.Na
«.NH
m.na
b.HH
o.Na
m.NH
e.mH
H.nH
O.hH
n.ma
v.fiN
m.ma
H.5H
m.va
h.Na
H.NH
n.Nfi
n.mN
o.vd
o.vH
m.na
e.MH

e.HH
m.OH
0.0H
m.m

e.m

m.Hfi
H.nH
h.VH
m.eH
h.mH
n.mH
n.md
n.0fi
d.NH
m.m

m.e

N.OH
e.HH
m.NH
o.nH
o.nfi
o.mH

h.HH
o.fiH
e.m

n.m

e.m

m.HH
0.0a
n.vH
e.eH
H.mfl
n.mH
v.bM
m.va
n.0d
v.m

v.e

e.m

N.OH
¢.HH
m.HH
O.Nd
m.NH

m.NH
N.NH
e.Ha
m.NH
H.NH
v.ma
m.VH
e.md
«.FH
m.ma
h.mfl
m.hH
m.mH
«.Na
o.m

v.5

e.m

e.m

n.0d
H.HH
v.HH
m.HH

e.nH
h.mH
o.vH
m.va
v.mH
N.efi
m.ea
e.bH
v.mH
«.mH
n.mfl
N.ma
v.0H
n.eH
m.Na
v.0a
m.m

w.m

N.OH
n.0a
m.oa
N.NH

m.vH
m.mH
m.eH
«.FH
0.0H
H.mH
fi.MH
v.mfl
m.md
n.0N
e.ON
e.ON
N.ON
e.mfl
v.ma
r.NH
N.HH
v.0H
H.0N
N.Od
n.0fi
m.OH

o.eH
m.eH
o.mH
v.mH
m.HN
N.HN
m.ON
m.ON
o.HN
m.NN
e.HN
m.HN
n.0N
o.mH
e.ea
N.¢H
v.NH
o.Hfi
H.0H
0.0a
«.0fl
m.0H

a.eH
h.ba
m.wH
H.0N
N.HN
e.fiN
h.aN
h.HN
m.HN
O.NN
N.NN
m.NN
m.ON
N.¢H
H.5H
N.mH
N.fifl
h.afi
n.0H
N.OH
n.0H
m.oa

v.bH
N.mH
N.mH
N.ON
o.dN
v.HN
O.NN
O.NN
H.NN
«.NN
N.NN
m.HN
b.0N
N.mfi
v.bH
h.mH
o.vfi
m.NH
v.HH
«.0H
m.0N
m.oa

h.bH
e.eH
m.mH
H.0N
b.0N
H.HN
o.NN
o.NN
H.NN
fi.NN
w.HN
m.HN
n.0N
H.mH
e.ha
a.eH
e.va
m.MH
v.NH
m.HH
m.HH
m.fia

e.hH
e.mH
H.mH
m.mH
n.0N
e.HN
w.aN
0.NN
o.NN
m.HN
v.flN
m.ON
0.0N
o.mH
e.bH
v.efi
N.mfi
o.vfi
O.MH
n.N~
N.NH
O.NH

6.
m.
m.
s.
m.
N..
N.
m.
m.
o.
o.
o.
m.
a.
N.
w.
o.
N.
m.
N.
m.
0.

5H
mH
0H
mH
mH
HN
HN
HN
NN
HN
fiN
ON
ma
ma
ha
eH
mH
«H
ma
MH
NH
Na

AUNNEN mmsz> 323:3:me

.2383 ON 638

141

A
E ooooooooooooooooooooo
O
8 ooooooooooooooooooooo
w
£2
0'.) ooooooooooooooooooooo
1]
.g ooooooooooooooooooooo
m
>
ll ooooooooooooooooooooo
CD
'2“ ooooooooooooooooooooo
m
13
C ooooooooooooooooooooo
3
C)
D ooooooooooooooooooooo
13
(U
2 ooooooooooooooooooooo
I
13
8 ooooooooooooooooooooo
'C
L)
(I) ooooooooooooooooooooo
m
L.
Cl

1220 1220 1220 1220 1220 1220 1E20 1320 1820 1220 1220 1320 1320 1220 1320 1320 1E20 1220 1220 1220 1220 1220 1220 1320 1820 1320

Storativity values (1 E20

,;
:0
E
O
8
O
v.
9
.Q
(U
P-

000000000000000000000
000000000000000000000
NNNNNNNNNNNNNNNNNNNNN
NNNNNWNNNMNNNNNNNNNMM
flHHHflHHHHr‘HHHNfiHHr-lr‘fifl

 

Tabie 1O (cont’d).

Recharge/discharge values (+ recharge, - discharge) (mm/yr).

142

 

143

«on
mom
new
mom
Nor.
can
mmv
mow
mmv
«on
new
mom
MHn
uHm
NNn
mNn
nnn
mnn
nvm
m vm
0mm
mmm

«an
«on
non
mom
com
mmv
wow
emu.
now
«on
«on
won
«an
ham
Nun
hNn
vnn
035:
03...
man
own
«or.

«Hm
OHm
hon
non
Hon
mnv
mac
bow
mmv
Non
von
hon
«Hm
0.3.
«Na
mun
vnm
own
hvn
wmn
Von
nun

on
nun
OHm
mom
won
non
mom
com
mon
non
new
mom
«am
ham
nun
awn
«mm
ovm
nvm
mnn
won
hum

mHn
nHm
nan
Nam
«Hm
MHm
can
mHn
«am
can
mom
can
hit.
man
vwm
onn
0mm
.nvn
fivn
own
Hon
mum

NNm
mam
man
ham
mHm
mum
hum
va
mam
Man
«an
Ham
mam
Hum
wan
nnm
mmn
m3.
onm
mmm
«on
own

hNn
HNm
man
.nNm
nun
«mm
wmm
nnm
mum
own
Tun
«Hm
ham
MNm
awn
nnm
an
Nun
vom
wmn
won
«an

onn
wNm
mwn
on
onn
mmm
mnn
bnn
mmm
th
our.
own
NNm
mNm
nnn
mnm
nvm
mmn
New
bum
mun
Ohm

mmm
Nnm
0mm
«mm
vnn
mmm
den
an
own
van
Nmm
.nmm
Nmm
mmm
mmm
new
mvm
vmn
vmm
vwm
Ohm
th

ovm
hnm
mnm
mnm
mmn
.nvm
nvm
bvn
o—‘m
wvn
nvm
mvn
uvm
nvn
wen
mvm
vnn
own
mwm
ohm
n5
mhm

Mvn
va
mmm
mnm
ovm
mvm
mvn
mmm
0mm
bnn
«mm
0mm.
mvm
omn
mmm
wmm.
new.
mom
hbm
mbm
hbm
0mm.

nvm
vvm
fivm
Nvm
vvn
mvm
vnm
mmn
«on
www-
amn
0mm
nmm
bmm
mmm
Num
own
firm
bhm
Ham
Hwn
Nam

mvm
mvn
mvm
mvm
0mm
mun
own
mwn
mwm
mom
her.
own
cum
mun
non
mmn
Ohm
fibn
urn
Hon
mom
can

«mm
«mm
can
nmm
hmm
Hon
mom
arm
mhm
mum
ohm
.nhn
now
Oh“
«hm
Mbn
chm
mhm
mhm
mmm
mmm
mmn

mmm
mnn
own
Hon
nwn
mwm
Nun
hhm
«mm
wan
5mm
nmn
ohm
ohm
mhn
ohm
arm
can
Nmn
mmn
Nam
bun

mum
won
wmm
00m
mom
chm
ohm
mwn
hmm
.nmn
flaw
mom
ban
wmm
man.
man
man
wmn
bmn
Nam
ham
Now

firm
mhm
firm
new.
wbm
own
«an
mmn
Nmm
man
man
wan
van
man
man
man
man
#9»:
man
man
«on
now

own
can
own
Hmn
vmm
hum
amn
man
man
000
Now
Now
How
.now
How
.noo
How
now
now
now
flaw
mac

mom
hon
mmm
mmm
Nam
man
man
How
vow
bow
wow
mow
moo
«om
mow
aom
Ode
NHo
mac
0;“
ONO
mum

mom
vmm
mom
vmm
man
Now
mow
mow
Haw
Mao
mac
wnw
maw
hfim
5H0
bac
mam
fiNm
mum
me
one
wa

now
now
vow
00w
boo
0am
Maw
93
«aw
HNm
NNw
vmo

me
“No
mNo
0N0
onw
mMu
mnw
mno
ovw

Mao
NHO
MHw
«Hm
wHw
me
.an
vuo
me
mNm
0mm
Nmm
mmw
vmw
mmw
mmw
«no
mflu
vvw
mvu
hww
mvw

NNw
HNw
.nNo
mmw
MNm
hum
me
«Mm
mmw
hmw
mmw
Owe
flvw
mvu
mvw
mvo
vvo
bvw
one
mmm
Mme
nnm

mNo
me
me
Hmw
mmw
mmw
mmm
ovw
mww
mvu
hvo
ave
one
Nmo
mmw
mnw
nmw
mmw
hum
mmw
own
«he

vmw
mmw
hmm»
mane
HVm
vvm
wvw
mvm
Hmw
mmw
nno
fine
mmm
wa
«om
Nmm
How
Nww
mwo
mum
how
mwm

mmo
fivw
wvw
wvm
mvm
wa
vmw
one
wmm
00m
wa
vow
woo
mow
mmm
mmm
mum
mbu
mmo
wa
firm
whw

E; $8: _35

.86 09285 9: 965509 5me mo_ mco$> B cozflzEB L8 Emu SQE .: 2an

 

144

OOOOOOOOOOOOOOOOOOOOOO

0 «.NH w.ma m.VH o.ma N.nH o.nH m.va N.nd N.NH m.HH b.dfl m.Na w.nfi m.VH o.wd m.wa v.ha b.hfl m.hH w.hd
o m.aH v.mH 0.mfi o.mH F.FH o.hH h.nH m.MH H.Nd m.oa o.HH fi.NH h.nH m.nH m.wH F.FH «.md w.mn w.mH m.mH
H.VN m.m~ n.dN v.0N H.0N n.mH N.hH m.va m.HH 0.0“ 0.0 o.HH o.VH m.wH o.wH m.wH N.mH m.mH fl.mH m.ma
N.HN O.MN o.nN h.flN O.HN u.flN b.flN m.mfi m.<d h.dH 0.0 m.m m.HH m.va v.bfi v.mH a.ON N.0N H.0N m.mH v.MH
o n.0N n.HN 0.0N h.ma «.mH N.ON n.0N m.hH m.va o.NH o.m v.m H.NH v.Mfl m.mH m.HN N.HN o.aN n.0N n.0N m.mH
o n.0H m.aH m.mH m.md n.uH N.0H o.hH «.FH n.wH m.VH o.NH m.Hfi m.fiH v.na N.0H «.ma N.HN 0.HN v.HN H.HN w.aN v.HN
o m.md n.mfl h.mH N.ad H.5H H.VH v.MH o.va o.va m.va m.va o.nH H.nH o.na m.va w.md a.mH m.ON h.HN O.NN o.NN m.HN h.«N
n.N~ n.mH m.mH n.0N n.aH h.efi h.ma h.HH v.HH 0.Na H.VH o.mfi H.ma b.¢H m.vH w.md o.bfi «.mfl 0.0N h.aN o.NN o.NN O.NN m.HN
O.NH v.nH n.0H u.NN w.mH n.wd N.MH H.0H m.m N.HH N.Vfl m.wd 0.FH m.wH o.wH N.hH v.mfi w.ma o.HN m.HN H.NN H.NN o.NN m‘HN
o.Nfi o.NH n.nH N.mH 0.0H N.wa N.MH m.m v.5 n.HH m.nH h.mH m.mfi b.mH ”.mH m.mfi N.m« n.0N m.fiN o.NN N.NN H.NN m.AN m.aN
o.NH O.NH O.NH m.nH o.hH H.oa N.QH n.NH h.dH m.MH v.5H m.HN v.HN m.mfi n.wfi b.mH m.mH 0.0N w.HN N.NN N.NN m.HN v.HN o.aN
O.NH O.NH 0.Na m.vH n.mn n.wu 0.0H o.nfl o.nH n.wH n.mH fi.ON m.mfi n.mH v.5H m.bH N.mH m.0N m.fiN m.NN m.HN n.HN m.oN n.0N
o.NH o.Na o.NH h.va N.0H H.bH v.ha m.hH v.hfi m.bH m.mH N.mfi H.5H m.nH m.va m.nH v.mH N.ON b.0N n.0N b.0N n.0N 0.0N m.mfl
o.NH O.NH o.Nfi m.flH o.mH F.FH m.ma N.mH N.ma «.mfi o.mH 0.UH m.VH H.NH n.0H N.NH n.wa m.ma o.mfi «.mH N.mH a.ma o.mH m.mH
O.NH O.NH o.Nd O.NH h.va n.mH 0.0N 0.0N N.ON m.mH 0.5a v.nH h.NH m.m v.m o.m m.NH v.mH o.wH “.FH v.5H o.hH w.bH F.FH
o.NH O.NH o.Nd O.NH o.va n.mfl o.NN o.dN v.0N o.mH H.hH m.¢fi H.NH m.w v.w v.5 v.0H b.NH N.vH H.mH b.mH H.mH v.mH w.ma
o o O.Nfl o.NH N.VH m.ma m.HN F.0N m.mH n.mH r.oH m.va n.NH N.Od w.m m.m m.m N.aa v.Nd N.NH o.vH o.va «.ma m.mH
o o O.NH o.NH u.mH o.mH H.mH fi.mH H.0H n.hH v.ofl o.nH m.na w.Ha N.Ofi m.m m.m v.0H o.HH h.aH m.NH m.ma o.va h.VH
o o.NH O.Nfl u.nH m.mH 0.FH m.MH «.md o.hd m.wH H.@H d.nH o.va m.Nfl v.HH n.0H N.oa fi.OH H.0fi n.0d v.aH v.NH o.mH m.ma
O.Nd O.NH n.NH m.mH o.mfi «.FH m.nH v.va m.mH d.md m.mH m.VH O.VH o.ma m.HH d.HH n.0H N.oa 0.0H N.oa a.oa m.fiH m.NH N.mH
d.NH n.VH N.nd v.0H n.5fi n.0H N.mfi m.vd n.nH m.nH H.na m.VH m.ma o.mH o.Nd v.da m.0H n.0fl v.0a n.0H m.oa m.H« N.N« m.NH
.Na «.NH o.nH h.nn v.wa 5.0H N.uH o.mH n.mH N.nH N.mH m.vn v.wH o.mH o.MH fl.Nfi m.flH N.HH m.0H w.0fl m.OH a.oa m.HH o.NH 0.Na

000000
00°00
0000

O

6C5 mo:_m> 3_>_mw_.EwcmC

.3083 S 993

 

Table 11 (cont’d).

variable-head cell).

prescribed-head boundary; 0 =

Storativity values (1 E20

1820 1220 1220 1320 1E20 1220 1320 1220 1820 1220 1320 1220 1220 1320 1220 1220 1220 1320 1220 1220 1220 1320 1220 1320 1320 1320

O
0
0
0
O
0
0
0
0
0
O

1220
1320
1220
1820
1220
1220
1220
1220
1820
1820
1820
1320
1320
1220
1220

145

0
O
0
0
0
0
0
0
0
0

1220
1220
1220

1320
1820

1220

Table 11 (cont’d).

Recharge/discharge values (+ recharge, - discharge) (mm/yr).

0
0
0
0
0
0

-.5 1.0
1.0 1.0
1.0 1.0
1.0 1.0

-.5
-.5

-.5 1.0

-.5

-.5

1.0

0
0

0
0
1.0

1.0 1.0 1.0
1.0 1.0 1.0 1.0

O

O

146

0 1.0 1.0 0
O 0

O
O

 

 

LIST OF REFERENCES

LIST OF REFERENCES

Ackerman, D. J., 1977, Ground-water basic data for Morton County, North
Dakota: North Dakota Geological Survey Bulletin 72—Part ll, 592 p.

--, 1980, Ground water resources of Morton County, North Dakota: North
Dakota Geological Survey Bulletin 72-—Part Ill, 51 p.

Anna, L. 0., 1980, Ground water data for Billings, Golden Valley, and Slope
counties, North Dakota: North Dakota Geological Survey Bulletin 76-—
Part II, 241 p.

—, 1981, Ground-water resources of Billings, Golden Valley, and Slope
counties, North Dakota: North Dakota Geological Survey Bulletin 76--
Part III, 56 p.

--—, 1986, Structural influences on Cretaceous sedimentation, Northern Great
Plains, in Peterson, J. A., ed., Paleotectonics and sedimentation in the
Rocky Mountain region, United States: American Association of
Petroleum Geologists Memoir 41, p. 173-191.

Armstrong, C. A., 1978, Ground-water resources of Emmons County, North
Dakota: North Dakota Geological Survey Bulletin 66—Part Ill, 43 p.

Arnason, B., 1981, Ice and snow hydrology, in Get, J. R., and Gonfiantini, R.,
eds, Stable isotope hydrology: Deuterium and Oxygen—18 in the water
cycle: Vienna, International Atomic Energy Agency Technical Report
Series No. 210, p. 143-176.

Bentley, H. W., Phillips, F. M., and Davis, S. N., 1986, Chlorine-36 in the
terrestrial environment, in Fritz, P., and Fontes, J. C., eds, Handbook of
environmental isotope geochemistry: New York, Elsevier, v. 2, p. 427-480.

Bickley, W. B., Jr., 1972, Stratigraphy and history of the Sakakawea Sequence,
south-central North Dakota [Ph.D. Dissertation]: University of North
Dakota, Grand Forks, 183 p.

Bluemle, J. P., 1984, Geology of Emmons County, North Dakota: North Dakota
Geological Survey Bulletin 66—-Part I, 69 p.

—--, 1988, Generalized bedrock geologic map of North Dakota: North Dakota
Geological Survey Miscellaneous Map 28.

147

 

 

 

 

 

148

Boulton, G. S., and Dobbie, K. E., 1993, Consolidation of sediments by glaciers:
relations between sediment geotechnics, soft—bed glacier dynamics and
subglacial ground-water flow: Journal of Glaciology, v. 39, p. 26—44.

Bredehoeft, J. D., Neuzil, C. E., and Milly, P. C. D., 1983, Regional flow in the
Dakota Aquifer: A study of the role of confining layers: US. Geological
Survey Water-Supply Paper 2237, 45 p.

Butler, R. D., 1984, Hydrogeology of the Dakota Aquifer System, Williston Basin,
North Dakota, in Jorgensen, D. G., and Signor, D. C., eds., Proceedings
of the Geohydrology Dakota Aquifer Symposium: Worthington, OH, The
National Water Well Association, p. 14-23.

Carlson, C. G., 1982, Geology of Grant and Sioux Counties, North Dakota: North
Dakota Geological Survey Bulletin 67-—Part I, 32 p.

--, 1983, Geology of Morton County, North Dakota: North Dakota Geological
Survey Bulletin 72-Part I, 37 p.

Clayton, L., 1969, Preliminary geologic map of Dunn County, North Dakota:
North Dakota Geological Survey Miscellaneous Map 11.

Clayton, L., and Moran, S. R., 1982, Chronology of Late Wisconsinan glaciation
in middle North America: Quaternary Science Reviews, v. 1, p. 55-82.

Craig, H., 1961, Isotopic variations in meteoric waters: Science, v. 133, p. 1702-
1703.

Croft, M. C., and Wesolowski, E. A., 1970, Transmissivity and storage coeffi
cient of aquifers in the Fox Hills Sandstone and the Hell Creek Formation,
Mercer‘and Oliver counties, North Dakota: US. Geological Survey
Professional Paper 700—B; p. 190-195.

Croft, M. G., 1970, Ground-water basic data, Mercer and Oliver counties, North
Dakota: North Dakota Geological Survey Bulletin 56—-Part II, 268 p.

---, 1973, Ground-water resources of Mercer and Oliver counties, North Dakota:
North Dakota Geological Survey Bulletin 56-—Part III, 81 p.

---, 1974, Ground-water basic data for Adams and Bowman counties, North
Dakota: North Dakota Geological Survey Bulletin 65--Part II, 294 p.

——-, 1985a, Ground-water data for McKenzie County, North Dakota: North Dakota
Geological Survey Bulletin 80-Part II, 455 p.

---, 1985b, Ground—water resources of McKenzie County, North Dakota: North
Dakota Geological Survey Bulletin 80——Part Ill, 57 p.

Dansgaard, W., 1964, Stable isotopes in precipitation: Tellus, v. 16, p. 436-468.

149

Dansgaard, W., and Tauber, H., 1969, Glacier Oxygen-18 content and
Pleistocene ocean temperatures: Science, v. 166, p. 499—502.

Davis, S. N., and Bentley, H. W., 1982, Dating groundwater: a short review, in
Currie, L. A., ed, Nuclear and chemical dating techniques: American
Chemical Society, p. 187-222.

Downey, J. S., 1986, Geohydrology of bedrock aquifers in the Northern Great
Plains in parts of Montana, North Dakota, South Dakota, and Wyoming:
US. Geological Survey Professional Paper 1402-E, 87 p.

Drever, J. I., 1982, Geochemistry of natural waters: Englewood Cliffs, New
Jersey, Prentice-Hall, 388 p.

Filley, T. H., 1985, The hydrogeological response to continental glaciation [MS
Thesis]: The Pennsylvania State University, 209 p.

Filley, T. H., and Parizek, R. R., 1983, Dynamics of groundwater flow associated
with a continental glacier: Geological Society of America Abstracts with
Programs, v. 15, p. 572.

Fontes, J. C., 1980, Environmental isotopes in groundwater hydrology, in Fritz,
P., and Fontes, J. C., eds, Handbook of environmental isotope
geochemistry: New York, Elsevier, v. 1, p. 75-140.

-—, 1981, Palaeowaters, in Gat, J. R., and Gonfiantini, R., eds, Stable isotope
hydrology: Deuterium and Oxygen-18 in the water cycle: Vienna,
International Atomic Energy Agency Technical Report Series No. 210,
p. 273-302.

Forman, S. L., Bettis III, E. A., Kemmis, T. J., and Miller, B. B., 1992,
Chronologic evidence for multiple periods of loess deposition during the
Late Pleistocene in the Missouri and Mississippi River Valley, United
States: Implications for the activity of the Laurentide Ice Sheet:
Palaeogeography, Palaeoclimatology, Palaeoecology, v. 93, p. 71-83.

Gat, J. R., 1981, Groundwater, in Gat, J. R., and Gonfiantini, R., eds, Stable
isotope hydrology: Deuterium and Oxygen-18 in the water cycle: Vienna,

International Atomic Energy Agency Technical Report Series No. 210,
p. 223-240.

Gerhard, L. C., and Anderson, S. B., 1988, Geology of the Williston basin
(United States portion), in Sloss, L. L., ed., Sedimentary cover——North
American craton; U.S: Boulder, Colorado, Geological Society of America,
v. D-2, p. 221—241.

Gerhard, L. C., Anderson, S. B., LeFever, J. A., and Carlson, C. G., 1982,
Geological development, origin, and energy mineral resources of
Williston basin, North Dakota: American Association of Petroleum
Geologists Bulletin, v. 66, p. 989-1020.

150

Gilkeson, R. H., Perry, E. 0, Jr., and Cartwright, K., 1981, Isotopic and geologic
studies to identify the sources of sulfate in groundwater containing high
barium concentrations: Urbana-Champaign, University of Illinois, Water
Resources Center, 39 p.

Groenewold, G. H., Cherry, J. A., Meyer, G. N., Hemish, L. A., Rehm, B. W., and
Winczewski, L. M., 1979, Geology and geohydrology of the Knife River
basin and adjacent areas of west—central North Dakota: North Dakota
Geological Survey Report of Investigation 64, 402 p.

Hamilton, T. M., 1970, Groundwater flow in part of the Little Missouri River
basin, North Dakota [Ph.D. Dissertation]: University of North Dakota,
Grand Forks, ND, 179 p.

Hoffman, P. F., 1989, Precambrian geology and tectonic history of North
America, in Bally, A. W., and Palmer, A. R., eds, The Geology of North
America—An overview: Boulder, Colorado, Geological Society of America,
v. A, p. 447-512.

Howells, L., 1982, Geohydrology of the Standing Rock Indian Reservation, North
and South Dakota: US. Geological Survey, Hydrologic Investigations
Atlas HA—644.

Hwang, W. J., 1982, Deuterium as a tracer in the groundwater study of a central
North Dakota mining area [MS Thesis]: North Dakota State University,
Fargo, 70 p.

Hyde, W. T., Crowley, T. J., Kim, K. Y., and North, G. R., 1989, Comparison of
GCM and energy balance model simulations of seasonal temperature
changes over the past 18,000 years: Journal of Climate, v. 2, p. 864-887.

IAEA, 1983, Stable isotopes of hydrogen and oxygen, in Isotope techniques in
the hydrogeological assessment of potential sites for the disposal of high-
Ievel radioactive waste: Vienna, International Atomic Energy Agency
Technical Report Series No. 228, p. 44-57.

Johnson, W. H., and Follmer, L. R., 1989, Source and origin of Roxana Silt and
middle Wisconsinan midcontinent glacial activity: Quaternary Research,
v. 31, p. 319-331.

Jouzel, J. J., Merlivat, L., and Lorius, C., 1982, Deuterium excess in an East
Antarctic ice core suggests higher relative humidity at the oceanic surface
during the last glacial maximum: Nature, v. 299, p. 688-691.

Kamb, B., 1987, Glacier surge mechanism based on linked cavity configuration
of the basal water conduit system: Journal of Geophysical Research,
v. 92, p. 9083—9100.

151

Kearl, P. M., Korte, N. E., and Cronk, T. A., 1992, Suggested modifications to
ground water sampling procedures based on observations from the

colloidal borescope: Ground Water Monitoring Review, v. 12, no. 2,
p. 155-161.

Kinzelbach, W., 1986, Groundwater modelling: Amsterdam, Elsevier, 333 p.

Klausing, R. L., 1979a, Ground-water basic data for Dunn County, North Dakota:
North Dakota Geological Survey Bulletin 68—-Part II, 501 p.

-—-, 1979b, Ground-water resources of Dunn County, North Dakota: North Dakota
Geological Bulletin 68—Part III, 48 p.

Lawson, D. E., 1993, Glaciohydrologic and glaciohydraulic effects on runoff and
sediment yield in glacierized basins: US. Army Corps of Engineers Cold
Regions Research & Engineering Laboratory, Monograph 93—2, 108 p.

LeFever, R. D., Thompson, S. C., and Anderson, D. B., 1987, Earliest Paleozoic
history of the Williston basin in North Dakota, in Carlson, C. G., and
Christopher, J. E., eds, Fifth International Williston Basin Symposium:
Regina, Saskatchewan, Saskatchewan Geological Society, p. 22-36.

Lobmeyer, D. H., 1985, Freshwater heads and ground-water temperatures in
aquifers of the Northern Great Plains in parts of Montana, North Dakota,
South Dakota, and Wyoming: US. Geological Survey Professional Paper
1402-D, 11 p.

Mathews, W. H., 1974, Surface profiles of the Laurentide ice sheet in its
marginal areas: Journal of Glaciology, v. 13, p. 37-43.

Maughan, E. K., and Perry, J., WJ, 1986, Lineaments and their tectonic
implications in the Rocky Mountains and adjacent Plains region, in
Peterson, J. A., ed., Paleotectonics and sedimentation in the Rocky
Mountain Region, United States: Tulsa, Oklahoma, American Association
of Petroleum Geologists Memoir 41, p. 41—53.

McGinnis, L. D., 1968, Glaciation as a possible cause of mineral deposition:
Economic Geology, v. 63, p. 390—400.

Merlivat, L., and Jouzel, J., 1979, Global climatic interpretation of the Deuterium-
Oxygen 18 relationship for precipitation: Journal of Geophysical
Research, v. 84, p. 5029-5033.

Mooers, H. D., 1990, Ice-marginal thrusting of drift and bedrock: thermal regime,
subglacial aquifers, and glacial surges: Canadian Journal of Earth
Science, v. 27, p. 849—862.

Moran, S. R., Arndt, M., Bluemle, J. P., Camara, M., Clayton, L., Fenton, M. M.,
Harris, K. L., Hobbs, H. C., Keatinge, R., Sackreiter, D. K., Salomon, N.
L., and Teller, J., 1976, Quaternary stratigraphy and history of North
Dakota, southern Manitoba, and northwestern Minnesota, in Mahaney, W.

152

0, ed., Quaternary stratigraphy of North America: Stroudsburg, PA,
Dowden, Hutchinson & Ross, |nc., p. 133-158.

Moser, H., and Stichler, W., 1980, Environmental isotopes in ice and snow, in
Fritz, P., and Fontes, J. C., eds, Handbook of environmental isotope
geochemistry: New York, Elsevier, v. 1, p. 141-178.

Panichi, C., and Gonfiantini, R., 1981, Geothermal waters, in Gat, J. R., and
Gonfiantini, R., eds, Stable isotope hydrology: Deuterium and Oxygen-18
in the water cycle: Vienna, International Atomic Energy Agency Technical
Report Series No. 210, p. 241-272.

Patch, J. C., and Knell, G. W., 1988, The Hydrogeology of the New Rockford
Aquifer System in Wells County, North Dakota: North Dakota State Water
Commission Ground-Water Studies 95, 178 p.

Paterson, W. S. B., 1981, The physics of glaciers [2nd ed.]: Elmsford, NY,
Pergamon Press Inc., 380 p.

Peter, K. D., 1984, Hydrochemistry of Lower Cretaceous sandstone aquifers,
Northern Great Plains, in Jorgensen, D. G., and Signor, D. C., eds,
Proceedings of the Geohydrology Dakota Aquifer Symposium:
Worthington, OH, The National Water Well Association, p. 163-174.

Randich, P. G., 1975, Ground-water basic data for Grant and Sioux Counties,
North Dakota: North Dakota Geological Survey Bulletin 67--Part II, 303 p.

-—, 1979, Ground-water resources of Grant and Sioux Counties, North Dakota:
North Dakota Geological Survey Bulletin 67—Part Ill, 49 p.

Robin, M. J. L., and Gillham, R. W., 1987, Field evaluation of well purging
procedures: Ground Water Monitoring Review, v. 7, no. 4, p. 85-93.

Ruhe, R. V., 1983, Depositional environment of Late Wisconsin loess in the
midcontinental United States, in Porter, S. 0., ed., Late-Quaternary
environments of the United States. I. The Pleistocene: Minneapolis, Univ.
Minnesota Press, p. 130-137.

Shreve, R. L., 1972, Movement of water in glaciers: Journal of Glaciology, v. 11,
p. 205-214.

Shurr, G. W., 1979, Lineament control of sedimentary facies in the Northern
Great Plains, United States, in Podwysocki, M. H., and Earle, J. L., eds,
Proceedings of the Second International Conference on Basement
Tectonics: Denver, Colorado, Basement Tectonics Committee, lnc.,

p. 361—370.

Siegel, D. I., 1983, Geochemical evidence for glaciation of the driftless area,
southern Wisconsin: Geological Society of America Abstracts with
Programs, v. 15, p. 687.

153

m, 1991, Evidence for dilution of deep, confined ground water by vertical
recharge of isotopically heavy Pleistocene water: Geology, v. 19,
p. 433-436.

Sloss, L. L., 1963, Sequences in the cratonic interior of North America:
Geological Society of America Bulletin, v. 74, p. 93-113.

Thomas, G. E., 1974, Lineament-block tectonics: Williston Blood Creek basin:
American Association of Petroleum Geologists Bulletin, v. 58, p. 1305-
1322.

—-, 1979, Lineament-block tectonics: North American Cordilleran Orogen, in
Podwysocki, M. H., and Earle, J. L., eds, Proceedings of the Second
nternational Conference on Basement Tectonics: Denver, Colorado,
Basement Tectonics Committee, lnc., p. 361—370.

Thorstenson, D. C., Fisher, D. W., and Croft, M. G., 1979, The geochemistry of
the Fox Hills-basal Hell Creek aquifer in southwestern North Dakota and
northwestern South Dakota: Water Resources Research, v. 15, p. 1479-
1498.

Trapp, H. J., 1971, Ground-water basic data, Hettinger and Stark Counties,
North Dakota: North Dakota State Water Commission County Ground
Water Studies 16 — Part II, 455 p.

Yurtsever, Y., and Gat, J. R., 1981, Atmospheric waters, in Gat, J. R., and
Gonfiantini, R., eds, Stable isotope hydrology: Deuterium and Oxygen—18
in the water cycle: Vienna, International Atomic Energy Agency Technical
Report Series No. 210, p. 103-176.

Zaporozec, A., 1972, Graphical interpretation of water quality data: Ground
Water, v. 10, p. 32—43.

 

 

 

 

 

 

 

5.1. .. .1

.3 r32}..!.
.3.

 

 

iii:

 

 

 

}. r s
2:. if... L:
.1.

 

 

. a: ...}.15.
.. .2. 4.21

LIBRQRIES

; 1:. r.
. Inn}? .... :, .

 

3.29.,,,,+]I]I]l]ll

. \
..r. J 1. e. 2.10...

.91.»...Zr... IPA l... {151:

z
,5...

it!

.I.» i. .I. pi
r. a

.Ju.fdm!..€..rl:rt. (..i

 
 

llllllllllllllllllllllllllllllll

l

.... C) s. («by . . v .3 . if
.32. .....v . . 113,7}. 3).
x: 1.......(!.1.). } 1.22:}.
.....z. ‘43:; c. ...}. i. ( ._

‘MICHIGQN STQTE UNIV

 

3.6.2; . t...

 

 

 

 

 

‘ .. (r
J ...”.t. "3.1.5. :7. 5...

. . . t , 219::
I 51......
t. 5...:

a

a

a.

pun-"n .-

 

v ...—N.....

':Ill.v-r(<;t;<;- ,. u

x:

 

p.;§€h;v I:

3"!»

n.3,;

"win-3

 

. 1. y .n......

b
w . . . .. . 5......
... .

z