United States
Environmental Protection
Agency
EPA 600/R-09/036 I April 2009 I www.epa.gov/ada
Flow Contribution and Water
Quality with Depth in a Test Hole
and Public-supply Wells:
Implications for Arsenic Remediation
through Well Modification,
Norman, Oklahoma, 2003-2006
^T. Lam nunOarUra
Land surface
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Office of Research and Development
National Risk Management Research Laboratory, Ada, Oklahoma 74820
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Flow Contribution and Water Quality
with Depth in a Test Hole and
Public-supply Wells:
Implications for Arsenic Remediation
through Well Modification,
Norman, Oklahoma, 2003-2006
S. Jerrod Smith
U.S. Geological Survey
Stanley T. Paxton
Oklahoma State University
Scott Christenson
U.S. Geological Survey
Robert W. Puls
U.S. Environmental Protection Agency
James R. Greer
U.S. Geological Survey
Office of Research and Development
National Risk Management Research Laboratory, Ada, Oklahoma 74820
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Notice
The U.S. Environmental Protection Agency through its Office of Research
and Development funded the research described here. It has been subjected to the
Agency's peer and administrative review and has been approved for publication as an
EPA document. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
All research projects making conclusions or recommendations based on
environmentally related measurements and funded by the Environmental Protection
Agency are required to participate in the Agency Quality Assurance Program. This
project was conducted under an approved Quality Assurance Project Plan. The
procedures specified in this plan were used without exception. Information on the
plan and documentation of the quality assurance activities and results are available
from the Principal Investigator.
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Foreword
The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the Nation's land, air, and
water resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement
actions leading to a compatible balance between human activities and the ability of natural systems to support and
nurture life. To meet this mandate, EPA's research program is providing data and technical support for solving
environmental problems today and building a science knowledge base necessary to manage our ecological resources
wisely, understand how pollutants affect our health, and prevent or reduce environmental risks in the future.
The National Risk Management Research Laboratory (NRMRL) is the Agency's center for investigation of
technological and management approaches for preventing and reducing risks from pollution that threatens human
health and the environment. The focus of the Laboratory's research program is on methods and their cost-
effectiveness for prevention and control of pollution to air, land, water, and subsurface resources; protection of water
quality in public water systems; remediation of contaminated sites, sediments and ground water; prevention and
control of indoor air pollution; and restoration of ecosystems. NRMRL collaborates with both public and private sector
partners to foster technologies that reduce the cost of compliance and to anticipate emerging problems. NRMRL's
research provides solutions to environmental problems by: developing and promoting technologies that protect and
improve the environment; advancing scientific and engineering information to support regulatory and policy decisions;
and providing the technical support and information transfer to ensure implementation of environmental regulations
and strategies at the national, state, and community levels.
This publication has been produced as part of the Laboratory's strategic long-term research plan. It is published
and made available by EPA's Office of Research and Development (ORD) to assist the user community and to
link researchers with their clients. Arsenic is a common ground-water contaminant at hazardous waste sites and a
widespread issue confronting many drinking water supplies in the U.S. The purpose of this document is to provide
a hydrologic and geochemical basis for assessing the potential for restoring existing water supply wells impacted by
elevated concentrations of arsenic from natural sources. This report will fill a need for a readily available source of
information for water supply managers and others who are faced with this problem. The information provided in this
document will be of use to stakeholders such as state and local environmental agencies, public water supply managers,
Native American tribes, consultants, contractors, and other interested parties.
Robert W~Fuls, Acting Director
Ground Water and Ecosystems Restoration Division
National Risk Management Research Laboratory
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Contents
Notice ii
Foreword iii
Figures vii
Tables ix
Plate ix
Acknowledgments x
Abstract xi
1.0 Introduction 1
2.0 Purpose and Scope 6
3.0 Description of the Study Area 7
City of Norman Water Use 7
City of Norman Well Field 8
City of Norman Well Construction 8
Hydrogeologic Setting: Central Oklahoma Aquifer 9
Conceptual Model of the Central Oklahoma Aquifer 12
Ground-water Flow and Geochemical Processes 13
Spatial Variability of Water Quality in the Deep Aquifer System 14
4.0 Approach and Methods 15
Selection of Wells for Investigation 15
Remediation Options 16
Methods of Hydraulic Data Collection 17
Flowmeter Logging and Straddle-packer Testing 17
USGS Well Profiler 18
Tracer-pulse Velocity Logging 20
Estimates of Total Well Yield 21
Techniques for Determining Flow Contribution by Open Intervals 21
Cross-sectional Area Computations 23
Hose Stretch 23
PVC Access Tube 24
Depth-dependent Sampling 24
Decontamination Procedures 26
Quality-assurance Procedures 26
Sample Analysis Methods 26
Filtered (dissolved) and Unfiltered (total) Samples 27
5.0 Norman Arsenic Test Hole 28
Norman Arsenic Test-hole Core 28
Norman Arsenic Test-hole Water Quality 29
6.0 Flow Contribution and Water Quality with Depth from an Eleven-well Investigation 33
Ground-water Flow and Particle-tracking Models 33
Traditional Methods of Hydraulic Testing - Well 23 34
USGS Well Profiler 36
Tracer-pulse Velocity Profiles 36
Estimates of Well Yield 38
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Depth-specific Water Quality 38
Isotopic Composition of Water from Wells 40
Major-ion Water-quality Trends with Depth 41
Iron Species 42
Other Characteristics Related to Arsenic Release in the Central Oklahoma Aquifer 42
Orthophosphate and Sulfate 42
Barium and Strontium 44
Boron 44
Chromium, Selenium, and Uranium 44
7.0 Comparison of Traditional Methods and USGS Well-profiler Methods 45
Differences in Flow Data 45
Differences in Water-quality Data 45
8.0 Implications for Arsenic Remediation: Well Modification and Well Response 47
Pump Relocation 47
Zonal Isolation 48
9.0 Summary 52
10.0 Selected References 54
11.0 Appendixes 58
Appendix 1. Photographs of Core from the Norman Arsenic Test Hole, 2004 59
Appendix 2. Description of Core from the Norman Arsenic Test Hole, 2004 72
Appendix 3. Chemical Analyses of Ground-water Samples and Quality-assurance Samples from
the Norman Arsenic Test Hole, Station Number 351645097253801, in October 2004 90
Appendix 4. Chemical Analyses of Ground-water Samples and Quality-assurance Samples
Collected to Assess Potential for Arsenic Remediation by Well Modification in 11 Selected
Public-supply Wells, Norman, Oklahoma, 2003-2006 92
Appendix 5. A-K. Illustrations of Natural Gamma-ray Logs, Open-interval Logs, Flow
Contribution, and Water Quality with Depth in 11 Selected Public-supply Wells, Norman,
Oklahoma, 2003-2006 112
Appendix 6. Chemical Analyses of Ground-water Samples and Quality-assurance Samples
Collected after Well Modification in Two Selected Public-supply Wells, Norman, Oklahoma,
2005-2006 123
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Figures
1. Map showing the Central Oklahoma aquifer and the municipalities that produce some ground
water for public supply and have discovered elevated arsenic concentrations in produced water. . . 2
2. Wells and range of median detected arsenic concentrations in the Norman well field, 2003 2
3. Map showing the extent and location of the Central Oklahoma aquifer with well-head arsenic
concentrations 5
4. Organizational structure of research activities in the Central Oklahoma aquifer. 6
5. Typical construction of a gun-perforated public-supply well showing deployment of the
combined well-bore flow and depth-dependent water sampler 8
6. Varieties of well-scale buildup in Cleveland County, Oklahoma 9
7. Surficial geology of the Central Oklahoma aquifer. 10
8. Generalized hydrogeologic section of the Central Oklahoma aquifer showing the location of the
Norman well field 11
9. Potentiometric contours and water type from deep wells in the Central Oklahoma aquifer. 13
10. Relation between dissolved arsenic concentration and pH for wells in the Central Oklahoma
aquifer. 14
11. Well-head concentrations, median values, and maximum contaminant levels for arsenic in the
Norman well field, 2003 15
12. Selected wells and surficial geology of the Norman well field, 2003 16
13. Apparatus used in straddle-packer testing of Norman Well 23 18
14. Photographs of the USGS well profiler and related equipment 19
15. Generalized horizontal well cross sections and unit area computations above and below the
pump intake in wells with a 10-inch casing and 4-inch pump column 20
16. Traveltimes determined by tracer-pulse method in Norman Well 23 in 2004 22
17. Traveltimes determined by tracer-pulse method in Norman Well 15 in 2004 22
18. Procedure for depth-dependent sampling with the USGS well profiler 24
19. Selected geophysical logs and water-quality samples from the deep aquifer system at the
Norman arsenic test hole, October 2004 29
20. Modeled flow paths for selected wells in the Norman well field 34
21. Typical modeled flow path for Norman Well 23 and trend in well-head arsenic concentrations. ... 35
22. Results of wireline logging, impeller-flowmeter, and packer tests in Norman Well 23,
September 2004 35
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23. Well-head arsenic concentrations, median values, and maximum contaminant levels for
arsenic in the Norman well field, 2003, with depth-dependent and well-head arsenic
concentrations from 11 selected wells, 2003-2006 39
24. Plot of 518Oxygen and SDeuterium for selected wells in the Norman well field 40
25. Piper diagram showing water types in the arsenic test hole and selected wells in the Norman
well field, with data from Schlottmann and others 42
26. Graphs of selected constituent concentrations that are related with arsenic concentrations in
Norman wells 43
27. Results of pump intake relocation in Norman Well 05 48
28. Results of pump intake relocation in Norman Well 36 49
29. Results of attempted zonal isolation in Norman Well 36 by using a retrievable bridge plug 50
30. Log of well yield and selected well-head water-quality constituents at Norman Well 36 during
an attempt at zonal isolation by using a retrievable bridge plug 51
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Tables
1. Selected construction information and arsenic concentration statistics for public-supply wells
in the Norman well field, 2003 3
2. Annual water production by the City of Norman, 1983-2003 7
3. Summary of sample water use and analysis types in order of collection 25
4. Well-head values and maximum and minimum values of constituents measured in
depth-dependent samples from 11 selected wells, Norman, Oklahoma, 2003-2006 37
5. Estimated well yields determined from tracer-pulse velocity profiling for 11 selected wells in
Norman, Oklahoma, 2003-2006 39
Plate
1. Caliper, natural gamma-ray, resistivity, and neutron logs from the Norman arsenic test hole,
SE1/4, Section 5, Township 09 North, Range 02 West 31
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Acknowledgments
The authors express their thanks to employees of the City of Norman, who allowed access to wells and offered
assistance at every opportunity. Contributions by Bryan Hapke, Chris Mattingly, Geri Wellborn, the late Vernon
Campbell, and the staff of the Vernon Campbell Water Treatment Plant are especially appreciated. The authors also
acknowledge Ken Komiske and Bryan Mitchell of the Norman Utilities Department, and the Norman City Council for
their support of this research project. The authors also thank John Izbicki and Allen Christensen of the USGS California
Water Science Center for their willingness to share their field experience and technical expertise.
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Abstract
The City of Norman, Oklahoma, is one municipality affected by a change in the Environmental Protection Agency's
National Primary Drinking Water Regulation for arsenic. In 2006, the maximum contaminant level for arsenic in
drinking-water was lowered from 50 to 10 micrograms per liter. Arsenic concentrations in water produced by 32
Norman public-supply wells ranged from less than 1 to 232 micrograms per liter. Some Norman wells with arsenic
concentrations marginally exceeding 10 micrograms per liter are suspected of producing water from zones with
acceptably low arsenic concentrations and zones with unacceptably high arsenic concentrations. If water with high
arsenic concentrations can be limited or excluded from production without causing an excessive decrease in well yield,
these wells may be rehabilitated to comply with the new regulation.
The flow contribution and water quality of each producing zone was measured in 11 City of Norman wells to
determine which wells were potential candidates for arsenic remediation by well rehabilitation. Depth-dependent
flow-contribution and water-quality data were collected under normal production conditions using the U.S. Geological
Survey combined well-bore flow and depth-dependent water sampler (U.S. Geological Survey well profiler). The
depth-dependent water-quality data collected by the U.S. Geological Survey well profiler were extremely useful as a
qualitative tool for identification of zones that degrade water quality in the Norman wells. The depth-dependent water-
quality data, even without flow-contribution data, showed the depth at which the water mixture in the well bore was
unsuitable for public supply.
Eleven Norman wells were investigated for remediation potential. Most of the selected wells (Wells 06, 07, 13, 15,
18, 23, and 31) showed elevated (greater than 10 micrograms per liter) or near-elevated arsenic concentrations at all
depths in the well. For these wells, well-modification techniques would be ineffective in lowering well-head arsenic
concentrations to less than 10 micrograms per liter. Wells 02, 05, 33, and 36 showed potential for successful application
of well modification techniques for arsenic remediation because greater differences in arsenic concentrations between
depths were observed.
Two of the eleven selected wells (05 and 36) were selected for repeated sampling to determine the effects of pump
intake relocation on well yield and water quality. Both wells had elevated arsenic concentrations in water from
the deepest zone and arsenic concentrations less than 10 micrograms per liter in water from shallower zones. Both
wells showed short-term improvements in water quality as the pump was moved to higher locations in the well. In
Well 05, arsenic concentration at the well head decreased by about 32 percent and well yield decreased by 12 percent.
In Well 36, arsenic concentration at the well head decreased by 84 percent and well yield increased by 13 percent.
However, additional samples collected a few months later in Well 36 revealed that improvements in well-head water
quality were only temporary.
An alternate remedial approach of zonal isolation was implemented in Well 36. Only the deepest zone in Well 36 (648-
658 feet below land surface) was suspected of contributing elevated arsenic concentrations to the well. A retrievable
bridge plug was installed at a depth of 640 feet in Well 36 to isolate the suspect zone from production. Unfortunately,
the installation of the bridge plug had little effect on well-head water quality. Compared to well-head samples collected
prior to the installation of the bridge plug, specific conductance and concentrations of arsenic and chromium at the well
head each decreased by only 2 percent after installation of the bridge plug. However, the bridge plug may have been
placed too deep to exclude the arsenic-contaminated water from production.
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1.0
Introduction
Arsenic in ground water is a major issue affecting many
municipalities and water districts in the United States,
especially those in the West, Midwest, and Northeast
(Welch et al., 2000). Arsenic concentrations in ground
water also are locally elevated in many other parts of
the United States. Many public-water supply systems,
including several systems in central Oklahoma, depend
on ground water from aquifers in which arsenic has been
identified as a naturally occurring contaminant.
Arsenic is a known carcinogen (World Health
Organization, 2001). Ingestion of inorganic arsenic, of
which 30-90 percent may be supplied by drinking water,
is believed to cause bladder, kidney, lung, and liver
cancer in humans (Smith et al., 1992). An individual's
risk of dying from arsenic-related cancers as a result of
lifetime ingestion of water with arsenic concentration at
50 micrograms per liter (|J.g/L) could be as great as 13
in 1,000 (Smith et al., 1992). To address this risk, the
U.S. Environmental Protection Agency (EPA) completed
a review of the 1986 National Primary Drinking-
Water Regulation for arsenic in 2000 (EPA, 2001).
After considering the available research on the health
effects of arsenic consumption, the EPA chose to lower
the arsenic maximum contaminant level (MCL) from
50 |ag/L to 10 |ag/L (EPA, 2001). The EPA estimates
that about 3,000 community water systems, including
municipal water-supply systems, must employ treatment
techniques to meet the revised regulation, which became
enforceable on January 23, 2006 (EPA, 2001). Since
that time, many water suppliers have been seeking
ways to maintain their current level of water production
and provide the public with safe, clean drinking water.
Chemical treatment of arsenic in ground water is
generally cost- and maintenance-prohibitive and remains
an option for only the largest water suppliers. Well-head
treatment is a potential option, but the costs associated
with filter media replacement and disposal, sometimes
as hazardous waste, are often too great for smaller
municipalities and water districts. Multiwell blending
is an available option, but blending often requires the
installation of expensive conveyance infrastructure. Well
modification to exclude or limit production of arsenic-
bearing water is a simpler and more cost-effective
solution, but not all wells are good candidates for this
remediation technique.
The 2006 change in the arsenic MCL has affected
several municipalities in central Oklahoma, including
Edmond, Moore, Mustang, Nichols Hills, Noble,
Norman, Piedmont, and Yukon (Figure 1), which operate
wells in the Central Oklahoma (Garber-Wellington)
aquifer. The City of Norman is one of the most affected
municipalities in terms of the number of wells in which
produced water exceeds 10 |ag/L arsenic (Jon Craig,
Oklahoma Department of Environmental Quality,
written commun., January 26, 2005). Historical arsenic
concentrations of produced water from 32 active
Norman public-supply wells ranged from less than
1 |ag/L to 232 |J.g/L. Based on maximum detected arsenic
concentrations in well-head samples, 11 of these wells
could be deemed noncompliant under the old MCL of
50 ug/L arsenic (Table 1). Of the 21 remaining wells,
10 additional wells, which account for about one-third
of the total well-field production capacity, likely will
be deemed noncompliant under the new arsenic MCL.
Through 2003, two-thirds of the wells in the Norman
well field had produced at least one well-head sample
with arsenic concentration greater than 10 |J.g/L.
The City of Norman considered several engineering
approaches to reduce arsenic concentrations in
water reaching the consumer. Blending water from
noncompliant wells with water from compliant wells to
dilute arsenic in the delivery system was suggested as
one cost-effective solution. Multiwell blending alone
would not be sufficient, however, to meet the new
MCL in most well groupings (CH2M-Hill, 2002). City
officials also considered chemical treatment options and
surface-water blending in an effort to reduce arsenic
concentrations before the water reaches the consumer.
These methods of arsenic remediation usually require
ground water be pumped to and blended or treated at a
treatment plant before the water can enter the distribution
system. If these methods are employed, the current
(2006) infrastructure and capacity of the water treatment
plant are insufficient to satisfy peak demand during
the summer months. Unfortunately, these solutions are
expensive for municipalities and consumers.
According to one study, the most cost-effective solution
currently is to abandon the high-arsenic wells and drill
new wells in low-arsenic areas (CH2M-Hill, 2002).
In the next phase of well construction, which began in
2006, the city will construct as many as 10 new wells in
northeast Norman (Bryan Mitchell, City of Norman, oral
commun., 2006). These wells will replace production
lost to the new arsenic rule and add new production to
keep up with rapidly growing demand.
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EXPLANATION
M Lake
I I Central Oklahoma aquifer boundary
EH County boundary
Municipalities
I I Edmond
CD Moore
I I Mustang
I I Nichols Hills
I I Noble
I ~ | Norman
I I Oklahoma City
I I Piedmont
I I Yukon
Easternmost outcrop of
Hennessey Group (dashed
where buried)
Stream
Location of
T potentiometric high
0 5 10 MILES
0 5 10 KILOMETERS
Central
Oklahoma
aquifer
Albers Equal-Area Conic Projection
Hydrography from Oklahoma Water Resources Board
Figure 1. Map showing the Central Oklahoma aquifer and the municipalities that produce some ground water
for public supply and have discovered elevated arsenic concentrations in produced water (Jon Craig,
Oklahoma Department of Environmental Quality, written commun., 2005). The City of Oklahoma City
(light yellow) uses only surface water for public supply. Many of the surrounding municipalities purchase
water from Oklahoma City to make up for well production lost to the revised arsenic drinking-water
regulation and to supplement supply during periods of high demand.
EXPLANATION
{ Water
Norman roads
Rivers and streams
Hennessey-Carber contact
Central Oklahoma aquifer boundary
- - Norman boundary
THA Norman arsenic test hole
Q Sampled wells, this study
20 Well number
Median detected well-head arsenic
concentration, in micrograms per liter
> 50
20-50
O 10-20
O 5 - 10
O < 5
0 0.5 1 2 MILES
I I 'I ' I '
0 0.5 1
KILOMETERS
-1 Hydrography from Oklahoma Water
Figure 2. Wells and range of median detected arsenic concentrations in the Norman well field, 2003.
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Table 1. Selected construction information and arsenic concentration statistics for public-supply wells in the Norman well field, 2003
Well
number
01
02
03
04
05
06
07
08
10
11
12
13
14
15
16
18
19
USGS station
number
351452097232201
351426097232201
351518097231801
351458097254901
351409097231801
351357097242001
351414097293901
351451097251701
351213097260001
351538097283401
351559097283601
351550097283801
351609097284601
351648097285101
351643097285601
351726097290901
351742097291501
Completion
method
Screen or
wire wrap
Screen or
wire wrap
Screen or
wire wrap
Gun
perforated
Gun
perforated
Gun
perforated
Gun
perforated
Gun
perforated
-
Slotted
casing
Slotted
casing
Gun
perforated
Gun
perforated
Gun
perforated
Slotted
casing
Gun
perforated
Gun
perforated
Year
drilled
1963
1963
1963
1964
1982
1982
1982
1982
-
1942
1944
1951
1952
1953
1953
1953
1953
Approximate
yield,
in gallons
per minute
200
335
230
215
212
218
182
228
177
144
193
190
182
164
122
147
174
Approximate
well depth,
in feet
693
732
726
--
695
645
745
--
567
635
670
678
--
674
--
693
700
Number of
available
well-head
samples
4
9
5
13
8
8
11
8
5
9
7
8
9
9
5
7
8
Number of well-
head samples
below method
detection limit
1
2
2
1
1
1
1
3
1
1
1
2
0
1
0
2
2
Minimum
detected arsenic
concentration,
in|ig/L
0.6
5.0
0.4
20.0
2.0
7.1
3.2
1.8
3.7
35.0
26.0
7.9
27.0
15.0
1.6
9.3
5.7
Median
concentration
of detections,
in|ig/L
1.3
10.1
0.9
47.0
12.0
9.4
14.5
1.9
7.7
67.0
69.3
11.3
47.0
36.5
34.0
10.8
9.8
Mean
concentration
of detections,
in|ig/L
2.3
9.8
0.8
58.3
30.2
10.6
17.5
2.1
7.3
61.5
67.6
17.3
49.1
36.1
25.1
12.4
9.9
Maximum
detected arsenic
concentration,
in|ig/L
5.0
13.0
1.1
112.0
150.0
16.0
28.0
3.0
10.0
82.0
102.0
32.0
79.7
53.0
39.0
20.0
15.0
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Table 1. Selected construction information and arsenic concentration statistics for public-supply wells in the Norman well field, 2003 (continued)
Well
number
20
21
23
24
25
31
32
33
34
35
36
37
38
39
40
USGS station
number
351807097292101
351314097254701
351401097252301
351357097255401
351358097245701
351542097262801
351530097252601
351541097245301
351530097242301
351609097242301
351633097241901
351633097233001
351609097232001
351548097231901
351541097224701
Completion
method
Gun
perforated
Gun
perforated
Gun
perforated
Gun
perforated
Screen or
wire wrap
Gun
perforated
Gun
perforated
Gun
perforated
Gun
perforated
Gun
perforated
Gun
perforated
Gun
perforated
Screen or
wire wrap
Gun
perforated
Gun
perforated
Year
drilled
1953
1955
1957
1957
1959
1997
1997
1998
1998
1998
1999
1999
2000
2000
2000
Approximate
yield,
in gallons
per minute
163
164
250
--
--
172
112
219a
257
144
260a
247
255
246
255
Approximate
well depth,
in feet
704
648
650
--
624
660
--
--
--
--
695
--
--
--
--
Number of
available
well-head
samples
8
12
31
2
8
4
4
3
4
5
5
4
5
5
5
Number of well-
head samples
below method
detection limit
2
0
0
0
0
0
1
1
1
3
1
0
3
1
2
Minimum
detected arsenic
concentration,
inug/L
2.9
21.0
14.0
230.0
41.0
16.0
16.0
1.3
0.9
0.8
0.7
0.8
0.8
4.0
0.4
Median
concentration
of detections,
inug/L
3.9
58.0
84.0
231.0
57.5
21.0
33.9
2.0
8.3
1.0
19.8
1.5
1.0
4.7
1.3
Mean
concentration
of detections,
inug/L
15.3
50.1
77.4
231.0
57.5
25.3
29.0
2.0
6.2
1.0
16.6
1.5
1.0
5.1
1.1
Maximum
detected arsenic
concentration,
inug/L
73.0
69.0
135.0
232.0
69.0
43.0
37.0
2.6
9.6
1.3
26.0
2.2
1.2
6.9
1.5
Measurements by City of Norman on 7-26-04
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The City of Norman produces ground water from
the Central Oklahoma (Garber-Wellington) aquifer,
a multilayered sandstone, siltstone, and mudstone
aquifer. Arsenic occurs naturally in small concentrations
throughout water of the Central Oklahoma aquifer,
but some areas are underlain by ground water with
arsenic concentrations much greater than the new MCL
(Parkhurst et al., 1994; Schlottmann et al., 1998). Most
elevated arsenic concentrations (greater than 10 ug/L)
occur in deep wells in the western, confined part of the
aquifer (Figure 3). The City of Norman recognized this
geographic trend in ground-water arsenic concentrations
at the well-field scale and stopped drilling new
exploratory test holes in western parts of the city. Since
1990, Norman well-field expansion has been almost
exclusively in the unconfined aquifer northeast of the
city. Arsenic concentrations measured in these newer
wells are often less than 10 ug/L.
EXPLANATION
Lake
I I Confined part of the
Central Oklahoma aquifer
I I Unconfined part of the
Central Oklahoma aquifer
I I County boundary
i ! City of Norman boundary
Stream
Well-head samples
Arsenic, total,
in micrograms per liter
No detection-10.00
10.01-50.00
50.01 - 232.00
Arsenic, dissolved,
in micrograms per liter
* No detection-10.00
* 10.01-50.00
* 50.01 -110.00
0 5 10 MILES
H-V-1
0 5 10 KILOMETERS
Central
Oklahoma
aquifer
Albers Equal-Area Conic Projection
Well data from U.S. Geological Survey
Hydrography from Oklahoma Water Resources E
Observations of elevated arsenic concentrations at depth
in the aquifer (Schlottmann et al, 1998) indicate that
well remediation could be employed to improve water
quality and retain production capacity at noncompliant
wells. Based on historical well-head samples, some
Norman wells with marginal arsenic concentrations
are suspected of producing water from zones with
both acceptably low and unacceptably high arsenic
concentrations. If water with high arsenic concentrations
can be limited or excluded from production without
causing an excessive decrease in well yield, these wells
may be rehabilitated to comply with the new arsenic
drinking-water regulation. To determine which wells
were potential candidates for arsenic remediation by well
rehabilitation, though, the flow contribution and water
quality of each producing zone needed to be measured in
individual wells.
Figure 3. Map showing the extent and location of the Central Oklahoma aquifer with well-head arsenic
concentrations (1977-2004). The dark shaded part of the aquifer represents the part that is confined by the
Hennessey Group. Deep municipal supply wells in the confined part are most likely to exceed the U.S.
Environmental Protection Agency maximum contaminant level for arsenic.
-------
2.0
Purpose and Scope
This report summarizes an investigation of ground-water
quality with depth and well-rehabilitation techniques
in one part of the Central Oklahoma aquifer. The study
location of Norman, Oklahoma, was selected because
the regional and local Central Oklahoma aquifer
systems have been well characterized after more than
20 years of concentrated research. Using this research
as a foundation, an investigation of individual well
construction and dynamics was undertaken to determine
if rehabilitation of water wells by well modification
is possible. The primary goals of this report are to
(1) present depth-specific water-quality data from a
test hole and selected public-supply wells that exceed
the 10 ug/L arsenic MCL, (2) describe the utility and
limitations of a new method for determining flow
contribution and water quality with depth in a pumping
well, (3) assess wells for the possibility of remediation
by well modification, and (4) evaluate the effectiveness
of well-modification approaches in bringing marginally
noncompliant wells into compliance with the 10 ug/L
arsenic MCL.
This report, which relies heavily on a conceptual model
of the Central Oklahoma aquifer system developed under
the U.S. Geological Survey (USGS) National Water-
Quality Assessment (NAWQA) Program, is presented in
three parts (Figure 4). The first part includes description
and analysis of cored sections, logs, and water samples
retrieved from a test hole in northern Norman. The
second part describes an 11-well investigation that
measured changes in water quality with depth to identify
wells that might be good candidates for remediation.
Included in this part are an analysis of ground-water flow
to selected wells and a comparison of selected techniques
for depth-dependent data collection in wells. The third
part documents attempts to decrease well-head arsenic
concentrations using well-modification techniques at two
City of Norman wells.
Concurrent with this report, a study (S.T Paxton,
Oklahoma State University, written commun., 2005)
provided a detailed stratigraphic framework of the
aquifer units that, in part, guided the selection of a
location for drilling, logging, coring, and water-quality
sampling of a test hole in the Norman area (Figure 4).
The purposes of the test hole were to (1) provide
information on water quality with depth in an area of the
aquifer that was relatively undeveloped and undisturbed
(prior to well completion and production), and (2) collect
rock material for laboratory analysis of rock and
water interactions (outside the scope of this report)
for proposed future research involving in-situ arsenic
remediation (Figure 4).
Conceptual model of the Central Oklahoma ^~~
aquifer developed by the USGS National Water-Quality
Assessment (NAWQA) Program
(Parkhurstetal., 1994; Parkhurstetal., 1996;
Christenson and Havens, 1998)
Norman
i
well field Cleveland County
Determination of flow contribution
and water quality with depth
(this report)
Test hole drilling, logging,
coring, and water-quality
sampling
Flow contribution and water
quality with depth (eleven-well
investigation)
Implications for arsenic
remediation by well
modification (two-well
investigation)
i
Stratigraphic study of Garber and
Wellington units of the Central
Oklahoma aquifer (S.T. Paxton,
Oklahoma State University,
written commun., 2005)
Outcrop characterization using
gamma-ray spectroscopy
(Gromadzki, 2004)
Outcrop description and
mapping of paleodepositional
environments (Kenney, 2005)
Subsurface well-log
correlation and mapping
(Abbott, 2005)
In-situ arsenic remediation
(proposed)
Figure
4. Organizational structure of research activities
in the Central Oklahoma aquifer.
By undertaking this project, the USGS and the EPA have
benefited from an improved description of the hydrologic
and geochemical controls on naturally occurring
arsenic with depth in an oxygen-rich aquifer. This
knowledge may benefit water suppliers in the United
States that draw high-arsenic water from multilayered
aquifers. With the prospect of identifying individual
wells for remediation using new depth-dependent
sampling techniques, the City of Norman may be able
to avoid costly installation of new wells, conveyance
infrastructure, and treatment technologies. Most
importantly, the City may be able to decrease arsenic
exposure to citizens and protect them against potentially
unnecessary costs associated with treatment.
-------
3.0
Description of the Study Area
The City of Norman is the county seat and primary
population center of Cleveland County, which occupies
536 square miles (U.S. Census Bureau, 2000) in the
southwestern part of the Central Oklahoma aquifer
(Figure 1). Norman was the third most populous city
in Oklahoma in 2000 (after Oklahoma City and Tulsa)
with about 95,000 residents (U.S. Census Bureau, 2000).
Norman also was one of the fastest-growing Oklahoma
municipalities of 20,000 or more people in 2000, with
an increase of 15,623 people (19.5 percent) since 1990
(U.S. Census Bureau, 2000). At the current growth rate,
the city population will exceed 200,000 by 2040.
City of Norman Water Use
Historically, the City of Norman has supplied
residents with municipal water from a combination of
ground-water and surface-water sources. Prior to the
impoundment of Lake Thunderbird (Figure 1) in 1965
and the construction of the Norman water-treatment
plant in 1966, Norman relied solely on ground-water
wells to supply drinking water to residents (City of
Norman, 2002). Since 1983, when the capacity of
the Norman water-treatment plant expanded, Lake
Thunderbird has served as the primary source of water
for the City of Norman. The annual allocation of Lake
Thunderbird water to Norman is 9,460 acre-feet (3,082
million gallons; City of Norman, 2002). Norman first
met this allotment in 1988, and has routinely met or
exceeded this allotment since 1995. In 2003, total water
production by the City of Norman was about 3,500
million gallons (City of Norman, 2004), which is slightly
less than previous years. About 79 percent of this total
was supplied by Lake Thunderbird (Figure 1), and about
20 percent was supplied by the Norman well field.
The City of Norman, like most other municipalities
in Central Oklahoma, maintains a connection to the
Oklahoma City water distribution system and can
augment supply in times of emergency or increased
demand by purchasing treated surface water from
Oklahoma City (City of Norman, 2004). In 2003,
Norman purchased about 53 million gallons (about
1 percent) of supplemental water from Oklahoma City
to satisfy peak demand during the summer months
(Table 2). However, the purchased water is provided at a
cost that is greater than the Norman water-rate structure
can support over long periods of time (City of Norman,
2002). To decrease annual water usage and reliance on
Oklahoma City, the City of Norman adopted a strategy
of conservation education paired with a water-rate
structure in which users with greatest consumption
purchase water at the greatest unit price (City of
Norman, 2002).
Because Norman and other municipalities surrounding
Oklahoma City began taking noncompliant wells out of
production in response to the new arsenic drinking-water
regulation, reliance on Oklahoma City supply is likely
to increase. Norman will need to add new water wells
to satisfy increasing demand and remain self-sufficient
in the future. A plan has been developed for placing
and constructing new wells, but Norman officials also
are interested in possible remediation of marginally
noncompliant wells.
Table 2. Annual water production by the City of
Norman, 1983-2003
Year
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
Total
production
(million
gallons)
2,956.4
2,803.6
2,903.7
2,847.3
3,006.2
3,425.5
3,163.2
3,427.2
3,458.8
3,277.7
3,534.1
3,714.0
3,912.3
3,965.5
3,811.5
4,572.4
4,291.8
4,366.7
4,446.6
4,289.2
3,463.0
Source
Treatment
plant (Lake
Thunderbird)
2,131.9
2,500.4
2,424.1
2,651.9
2,839.0
3,139.0
2,910.7
3,139.4
3,073.0
2,998.5
3,043.1
3,346.5
3,236.3
2,930.3
2,832.2
3,313.0
3,327.0
3,364.6
3,498.4
3,571.9
2,662.0
Well field
824.5
303.2
479.6
195.4
227.2
286.5
252.5
287.8
385.8
279.2
491.0
367.5
676.0
1,035.2
979.3
1,259.4
964.8
993.0
923.9
715.8
747.6
Purchase
from
Oklahoma
City
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
0.0
0.0
9.1
24.3
2.5
53.4
-------
City of Norman Well Field
The Norman well field consisted of 32 wells in the
Central Oklahoma aquifer in 2003 (Table 1, Figure 2).
Based on maximum detected arsenic concentrations in
well-head samples, 11 of these wells could be deemed
noncompliant under the old MCL of 50 ug/L arsenic
(Table 1). Of the 21 remaining wells, eight had median
detected arsenic concentrations greater than 10 ug/L
and ten had maximum detected arsenic concentrations
greater than 10 ug/L (Table 1, Figure 2). Eight to ten
additional wells, which account for about one-third of
the total well-field production capacity, likely will be
deemed noncompliant under the new arsenic MCL. The
loss of these additional wells will force the city to buy
additional water from Oklahoma City during the summer
months.
Though the oldest active wells in the Norman well
field were constructed in the 1940s, most older active
wells were constructed from 1951 through 1964
(Table 1). Older active wells are concentrated along
U.S. Highway 77 in northwest Norman (Figure 2).
Most of the younger wells were constructed from 1997
through 2000 and are located in the northeast part of the
well field (Table 1; Figure 2). In 2006, as part of a city
water plan, the city began construction of new wells in
the northeast part of the well field. In 2004, Norman also
acquired three additional wells when the City of Norman
annexed the community of Hall Park. These wells were
not included in this study. The University of Oklahoma
also operated several wells in the area of the Norman
well field; these wells were not included in this study.
City of Norman Well Construction
Well construction in the City of Norman well field
is typical of municipal well construction throughout
the Central Oklahoma aquifer. Most Norman public-
supply wells have a cement-annulus and gun-perforated
openings (Figure 5, Table 1). A smaller percentage of
wells have a gravel-pack annulus and screen, wire-wrap,
or slotted openings (Table 1).
Depths of Norman wells are usually 600 to 800 feet
below land surface (Table 1), and perforations
(openings through which water enters the well) begin
around 300 feet below land surface (Bryan Hapke,
City of Norman, oral commun., 2003). The density of
perforations across perforated intervals is usually 4 to
6 shots per foot, though some older wells may have
been reperforated to increase production. The number
of distinct perforated sandstone zones ranges from 5
to 21, but is most commonly around 10. Typically, the
upper perforated zones are considerably thicker than the
lower perforated zones. Individual sandstone zones in
the Garber Sandstone can exceed 40 feet in thickness,
but typically are from 5 to 15 feet in thickness. Open
(perforated or screened) intervals usually coincide with
a single, well-defined sandstone zone, but occasionally,
open intervals extend across multiple sandstone zones
with thin intervening mudstones (Figure 5).
USGS
well
profiler
30 60 70
NATURAL GAMMA-RAY
LOG, IN API UNITS
Figure 5.
Typical construction of a gun-perforated
public-supply well showing deployment
of the combined well-bore flow and
depth-dependent water sampler. (USGS
well profiler). Increased gamma radiation
generally indicates a greater percentage
of clay (mudstone) in the aquifer rocks.
Lesser gamma radiation indicates a coarser-
grained (sandstone) unit. Abbreviation: API,
American Petroleum Institute.
Casing diameter is 10 inches in all Norman wells except
Wells 31 and 32, which are 12 inches in diameter
(Bryan Hapke, City of Norman, oral commun., 2003).
Scale buildup is common, occasionally exceeding
0.125 inch in older wells and in sections near the water
level. Most scaling in the Norman well field is dark and
multicolored with presumed iron oxides (orange, yellow,
and red). Only some lighter-colored spots effervesced
with the application of dilute (5 percent) hydrochloric
acid. Another variety of scale is light-colored with
-------
white, cream, and pink layering (Figure 6). The light-
colored variety of scale is rich in calcium carbonate
as it effervesces strongly with the application of dilute
hydrochloric acid. The light-colored scale is a substantial
problem for well maintenance in parts of the city of
Moore, about 2 miles north of Norman (Robert Pistole,
Veolia Water, oral commun., 2005).
Dark-colored scale
Light-colored scale
Figure 6. Varieties of well-scale buildup in Cleveland
County, Oklahoma. The dark scale (left) is
typical of wells in the Norman well field. The
light scale (right) is more commonly found in
the southern Moore well field. Photographs
by Jerrod Smith, U.S. Geological Survey.
Lift in a Norman well typically is by a 40- to
60-horsepower submersible pump supported by a
column of 4- or 5-inch diameter steel pipe (Bryan
Hapke, City of Norman, oral commun., 2003). The
pump is typically installed near the bottom of the well,
usually within 100 feet of the bottom (Bryan Hapke,
City of Norman, oral commun., 2003; Figure 5). When
the pump is set below all perforations, a pump shroud is
sometimes installed for cooling purposes. The motor is
powered by a one-inch diameter electrical cable which is
banded to the pump column between pipe connections.
In some wells, centralizers were attached to the pump
column.
In 2006, the static water level in most selected Norman
municipal wells was from 300 to 500 feet below land
surface. The pumping water level was greater than
500 feet below land surface in one well in western
Norman. Drawdown, or the difference between the static
and pumping water levels in Norman wells, can be in
excess of 100 feet. Yield of Norman wells is usually
from 150 to 300 gallons per minute, though well output
across the well field ranges from about 100 to about
350 gallons per minute (Table 1).
Geophysical logs are available (from the City of
Norman) for nearly every well in the Norman well
field. Typically a natural gamma-ray or spontaneous-
potential log was used for qualitative determinations
of basic lithology. Often, a perforation log was noted
on the gamma-ray or spontaneous-potential log, and
each sandstone with a thickness of 5 feet or greater was
usually perforated. Natural gamma-ray logs are most
common, but not all gamma-ray logs were calibrated
to American Petroleum Institute (API) standard units.
On the gamma-ray log trace, deflections to the right
(higher values) indicate finer-grained mudstones and
deflections to the left (lower values) indicate coarser-
grained sandstones (Figure 5). Resistivity and neutron
logs are available for some wells and can yield useful
information about the zonal water content. For gun-
perforated wells, cement-bond logs are often available,
and bond is usually greater than 90 percent, indicating
few cavities between the casing and aquifer material.
Hydrogeologic Setting: Central
Oklahoma Aquifer
All wells in the Norman well field are completed in
the Central Oklahoma aquifer. The Central Oklahoma
aquifer, as defined by Parkhurst et al. (1994), underlies
about 3,000 square miles in parts of Cleveland, Lincoln,
Logan, Oklahoma, Payne, Pottawatomie, and Seminole
Counties. The aquifer is bounded by the Cimarron
River on the north, the Canadian River on the south,
and the easternmost outcrop of aquifer rocks on the
east (Parkhurst et al., 1994). The western boundary
of the aquifer is the Canadian-Kingfisher/Cleveland-
Oklahoma-Logan County line which approximately
represents the westernmost extent of freshwater
circulation (Figure 7; Parkhurst et al., 1994).
The Central Oklahoma aquifer is composed of the
Garber Sandstone, Wellington Formation, and Chase,
Council Grove, and Admire Groups of Permian age
(Figure 7). The overlying alluvial and terrace deposits
also are included in the aquifer (Figure 7) because
no confining layer underlies the alluvial and terrace
deposits, and ground water flows readily between these
deposits and the underlying Permian-age geologic units.
The Central Oklahoma aquifer is partially confined
above by Permian-age shale of the Hennessey Group
-------
EXPLANATION
Lake
Geologic Units
I I Alluvium
CD Terrace
^B Hennessey Group
CD Garber Sandstone
I I Wellington Formation
CC Chase, Council Grove, and
Admire Groups
I I County boundary
r_~ City of Norman boundary
Stream
10
20 MILES
0 5 10
20 KILOMETERS
Alters Equal-Area Conic Projection
Geologic data from Blngham and Moore (1975) and Hart (1974)
Hydrography from Oklahoma Water Resources Board
Figure 7. Surficial geology of the Central Oklahoma aquifer.
and below by Pennsylvanian-age shale of the Vanoss
Formation. The aquifer is unconfmed to the east of
Edmond, Oklahoma City, and Norman (Figure 1).
The Central Oklahoma aquifer is known locally as
the Garber-Wellington aquifer because the greatest
quantities of usable water are in the Garber Sandstone
and Wellington Formation (Garber-Wellington) of
Permian age. Though the Garber Sandstone and
Wellington Formation extend beyond the Central
Oklahoma aquifer boundary, these units typically do not
produce large quantities of water beyond the boundary.
The units include fine-grained, crossbedded sandstones
interbedded with siltstones and mudstones of fluvial-
deltaic origin (Parkhurst et al., 1994). Because the
Garber-Wellington contact is difficult to delineate in the
area of Norman, the Garber Sandstone and Wellington
Formation are treated as one unit in this report.
About 75 percent of the total thickness of the Garber-
Wellington is sandstone in southeastern Oklahoma
County (Parkhurst et al., 1994). The percentage of
sandstone decreases in all directions from southeast
Oklahoma County, reaching as little as 25 percent in
parts of Cleveland County south of Norman (Wood
and Burton, 1968). The total thickness of the Garber
Sandstone and Wellington Formation is usually from
1,100 to 1,600 feet (Christenson et al., 1992).
Annual rainfall in central Oklahoma is about 36 inches
(Johnson and Duchon, 1995). Recharge to the saturated
zone of the Central Oklahoma aquifer is estimated to be
1 to 2 inches per year (Parkhurst et al., 1996). According
to maps of the potentiometric surface of the aquifer,
rivers in the study unit are not a substantial source of
recharge (Parkhurst et al., 1996). Instead, potentiometric
contours of the Central Oklahoma aquifer indicate that
ground water discharges to most river systems, with
the notable exception of the North Canadian River
(Parkhurst etal., 1996).
Specific capacities computed for wells in the Central
Oklahoma aquifer range from 0.16 to 15 gallons per
minute per foot of drawdown, but are usually less than
5 gallons per minute per foot of drawdown (Parkhurst
et al., 1996). Transmissivities vary widely across the
aquifer, but median transmissivities computed by
Parkhurst et al. (1996) ranged from 260 to 450 square
feet per day. Computed hydraulic conductivities were
mostly from 2.5 to 10 feet per day, with a median of 4.5
feet per day (Parkhurst et al., 1996).
Given the economic importance of the aquifer,
surprisingly little published research has focused
on the stratigraphy of the Garber Sandstone and
Wellington Formation (Kenney, 2005). USGS NAWQA
-------
studies (Parkhurst et al., 1994; Parkhurst et al., 1996;
Christenson and Havens, 1998) have focused mostly
on the geochemical and geohydrologic characteristics
of the aquifer rather than the sedimentary geology.
Because a comprehensive understanding of the aquifer
system could not be achieved without some insight into
the stratigraphic framework of the aquifer, the EPA
commissioned an investigation of aquifer stratigraphy.
Gromadzki (2004), Abbott (2005), and Kenney (2005)
completed the most recent studies of the stratigraphy and
sedimentology of the Garber Sandstone and Wellington
Formation. The results of these stratigraphic studies
of the Garber Sandstone and Wellington Formation
were summarized and presented to EPA (S.T. Paxton,
Oklahoma State University, written commun., 2005).
The Garber Sandstone and Wellington Formation
consist of stacked channel bars, floodplain deposits,
and related fluvial facies (S.T. Paxton, Oklahoma State
University, written commun., 2005). These facies grade
into one another vertically and horizontally. The variable
lithofacies, lack of continuous marker beds, and scarcity
of fossils in the aquifer makes traditional stratigraphic
correlation difficult, especially over distances greater
than one mile (Abbott, 2005). The heterogeneous
stratigraphy also supports a complex ground-water flow
system with the potential for complex geochemical
interactions over time and space.
Schlottmann et al. (1998) divided the Central Oklahoma
aquifer into six geohydrologic zones on the basis of
changes in lithology, water chemistry, and the presence
of confined orunconfined conditions (Figure 8). Most
domestic, stock, and irrigation wells in the aquifer
draw water from the shallow (confined and unconfined)
aquifer system, which is less than 300 feet below
land surface. Wells in the shallow unconfined aquifer
system typically do not produce water with arsenic
concentrations greater than 10 ug/L (Schlottmann et
al., 1998; Becker, 2006). Most public-supply wells,
however, bypass the shallow aquifer system and produce
water from the deep (confined and unconfined) aquifer
system, which is greater than 300 feet below land
surface (Figure 8). Wells that tap the deep confined
aquifer system (like those in western Norman) are more
likely to exceed the arsenic MCL, according to statistics
calculated by Schlottmann et al. (1998). Schlottmann
et al. (1998) estimated that 30.2 percent of wells in
A. 1,
,500
1,000
500
Z SEA
Q LEVEL
i- West
-500
. Shallow
confined Norman well field
Land surface
East -,
.^hallow unconfined(2) ป
Lake Thunderbird
ฎ Sned ^
""--.. Lon9 Flowpath
Mfeier table
Short Row^a'th"^-30.p:feet.depth...,-. ;;.:....:,....,,:- @ Shallow
Deep unconfinedฉ
10
15 KILOMETERS
B. 1.500
1,000
500
Z SEA
Q LEVEL
-500
West
Norman well field
Modified from Schlottmann and others (1998)
East
Short Rowpath
Long Rowpath Mudstone dominates
BRINE
15 KILOMETERS
Note: The rock layers of the aquifer are nearly horizontal but appear to dip steeply to
the west because of vertical scale exaggeration. Vertical scale greatly exaggerated.
Modified from Schlottmann and others (1998)
Figure 8. Generalized hydrogeologic section of the Central Oklahoma aquifer showing the location of the Norman
well field. Red arrows illustrate theoretical long and short flow paths that supply water to the Norman well
field. Flow paths begin as recharge that enters the aquifer to the north of these cross-sections. The aquifer
is composed of six geohydrologic zones (A, 1-6) based on changes in lithology, water chemistry, and the
presence of confined or unconfined conditions. The amount of mudstone in the aquifer rocks (B) generally
increases with depth in the Norman well field, becoming the dominant lithology in the deep confined and
deep unconfined zones.
-------
the deep confined aquifer system produced water with
arsenic concentrations exceeding 50 ug/L, and that
only 2.4 percent of wells in the deep unconfined aquifer
system produced water with arsenic concentrations
exceeding 50 ug/L.
Conceptual Model of the Central
Oklahoma Aquifer
Arsenic is an element commonly found in aquifer rocks,
therefore most arsenic contamination in ground water
used for public supply results from natural processes.
In aquifers containing abundant iron oxides, arsenic
can become a natural water contaminant in two general
ways: (1) reductive dissolution of iron oxides, and
(2) desorption from iron oxides. The latter process is the
main cause of elevated arsenic in water of the Central
Oklahoma aquifer (Christenson et al., 1998). Arsenic in
ground water also commonly occurs in two oxidation
states: arsenite (As III) and arsenate (As V). These
arsenic species tend to occur as protonated oxyanionic
complexes in ground water (Stollenwerk, 2003). In this
report, unless otherwise noted, the word arsenic is used
to refer to all arsenic regardless of oxidation state.
The geohydrologic processes and geochemical
conditions in the Central Oklahoma aquifer are well
characterized as a result of monitoring conducted
during the USGS NAWQA Program. A series of
NAWQA-supported studies, beginning in the late
1980s and concluding in the mid-1990s, determined
the rock composition, water chemistry, and ground-
water movement in the Central Oklahoma aquifer. The
findings of these studies led to the development of a
comprehensive conceptual model of the aquifer system.
For detailed explanation and results of previous studies,
see Christenson and Havens, 1998 (USGS Water-Supply
Paper 2357-A) for a summary of NAWQA findings
with a focus on rock and water chemistry; Parkhurst
et al., 1994 (USGS Water-Supply Paper 2357-B) for a
retrospective analysis of available water-quality data
through 1987; and Parkhurst et al., 1996 (USGS Water-
Supply Paper 2357-C) for modeling and analysis of
geochemistry and ground-water movement through the
aquifer. Recent findings have expanded on the findings
of the NAWQA Program studies. Some of these findings
on water and rock characteristics, summarized briefly
here, formed a foundation for data interpretations in this
report.
Major characteristics of water in the Central Oklahoma
aquifer:
1. Dissolved arsenic concentrations range from <1 to
110 |ag/L and appear to exist almost exclusively as
arsenate (Ferree et al., 1992; Schlottmann, 2001);
2. Chromium, selenium, and uranium also exist
as oxyanions in the aqueous phase and behave
similarly to arsenate. Ranges of chromium,
selenium, and uranium concentrations in aquifer
water are <1 to 100, <1 to 190, and <1 to
318 |ag/L, respectively (Ferree et al., 1992);
3. Neutral to alkaline pH; pH ranges from 6.0 to 9.6
(Schlottmann et al., 1998); pH tends to be greater
in deeper wells (Becker, 2006);
4. Dissolved oxygen concentrations greater than
1 milligram per liter (mg/L) are present in most
water, indicating oxic conditions (Schlottmann,
2001);
5. Water can contain large concentrations of sulfate
and chloride in areas near the base of fresh
water, in the confined part of the aquifer, and
near the discharge areas of regional flow paths
(Schlottmann et al., 1998); and
6. Other constituents that may limit use of water
include fluoride and boron.
Major characteristics of rock in the Central Oklahoma
aquifer:
1. Predominantly sandstone, siltstone, and mudstone,
with some thin, localized conglomerates
(Gromadzki, 2004; Abbott, 2005; Kenney, 2005);
2. Dolomite cement is common to the conglomerate
and some sandstone and mudstone (Nkoghe-Nze,
2002; S.T. Paxton, Oklahoma State University,
written commun, 2005);
3. Cation-exchange capacity of clay-fraction
subsamples ranges from 20 to 50 milliequivalents
per 100 grams (Parkhurst et al., 1996);
4. Exchangeable sodium, as a percentage of
exchangeable cations in clay subsamples, is
greater in deeper sandstones than in shallow
sandstones; Exchangeable sodium is often less
than 1 percent in shallow sandstones (Parkhurst et
al., 1996);
5. Iron oxide and iron oxyhydroxide minerals are
present as cements and coatings on framework
grains in aquifer rocks (Parkhurst et al., 1996);
6. Evidence of paleosols (Sokolic, 2003;
S.T. Paxton, Oklahoma State University, written
commun, 2005);
7. Presence of reaction fronts indicating mobilization
(or dissolution and reprecipitation) of iron oxide
(Parkhurst et al., 1996; S.T. Paxton, Oklahoma
State University, written commun., 2005);
8. Arsenic concentrations range from <1 to
62 milligrams per kilogram (mg/kg) in drill-core
samples, with an average of 7.3 mg/kg (Mosier et
al., 1990);
-------
9. Average concentrations of chromium, selenium,
and uranium in drill-core samples are 56, 1.4, and
3.6 mg/kg, respectively (Mosier et al., 1990);
10. Elemental composition of drill-core samples
ranges from about 0.1 to 14 percent iron (Mosier
etal., 1990); and
11. Iron, arsenic, and dolomite concentrations are
all elevated in isolated conglomerate layers
(S.T. Paxton, Oklahoma State University, written
commun., 2005).
Ground-water Flow and Geochemical
Processes
Ground water in the Central Oklahoma aquifer originates
as infiltration from precipitation, a process known as
recharge. Where the aquifer is unconfmed, ground-water
recharge occurs areally, that is, everywhere the Garber
Sandstone, Wellington Formation, and alluvium and
terrace deposits are at the land surface. Ground water
in the unconfmed part of the aquifer mostly follows
relatively short flowpaths (on the order of feet to miles)
before discharging to streams (Parkhurst et al., 1996).
In the confined part of the aquifer, most ground-water
recharge originates in a relatively small area near a
potentiometric high centered in south-central Oklahoma
County (Figure 9). The potentiometric high corresponds
to a structural high that is expressed in contour maps of
the base of each aquifer unit (Christenson et al., 1992;
EXPLANATION
Lake
Water type
^f Calcium-magnesium-
bicarbonate
I I Calcium-magnesium-sodium-
bicarbonate
I I Calcium-magnesium-sodium-
bicarbonate-chloride-sulfate
CH Sodium-bicarbonate
I I Sodium-bicarbonate-sulfate
I I County boundary
ITi Norman
Stream
Potentiometric contours, in feet
above sea level
1300 1050
1250 1000
1200 950
1150 900
1100 850
+ Potentiometric high
Parkhurst et al., 1996). The potentiometric high also
corresponds to the part of the aquifer with the thickest
sequence of sandstone (Christenson, 1998). Ground
water in the confined part of the aquifer mostly follows
longer flowpaths (on the order of miles to tens of miles)
before discharging to streams.
In the area of the Norman well field, short and long
flow paths influence ground-water quality. Unconfined
ground water with short flow paths and short residence
times travels to the southeast through Cleveland County
and discharges relatively quickly to the Little River
drainage system near Lake Thunderbird (Parkhurst et
al., 1996; Figure 8). Estimated ages of water (times
since recharge) along short flow paths are on the order
of hundreds to thousands of years (Parkhurst et al.,
1996). Confined ground water with longer flow paths
and greater residence times travels to the southwest,
descending under the confining unit before turning back
to the east (Figure 8). Estimated ages of water along long
flow paths are on the order of tens of thousands of years
(Parkhurst et al., 1996).
In the unconfined part of the aquifer, recharge water
picks up carbon dioxide from the vadose zone, which
can make water mildly acidic. Dolomite, which is
present as cement in many aquifer rocks, dissolves to
equilibrium in the presence of carbon dioxide (Parkhurst
et al., 1996). The dissolution of dolomite causes a small
increase in pH, to values near neutral (7.0). The general
20 KILOMETERS
Albert Equal-Area Conic Projection
Water types In deep wells from paridiurst et al.. 1996
Potentfemetric contours from Christenson etal., 1992
Hydrography from OMehMne water Resources Board
Figure 9. Potentiometric contours and water type from deep wells in the Central Oklahoma aquifer.
-------
water type in the shallow, unconfined part of the aquifer
is calcium-magnesium-bicarbonate, identifying dolomite
dissolution as the dominant geochemical process
(Figure 9).
Deeper ground water comes in contact with aquifer
rocks (mudstone) rich in mixed-layer illite-smectite clay
minerals with high cation-exchange capacity (Figure 8).
Calcium and magnesium ions in the water are exchanged
for sodium ions in the clays. When calcium ions
leave the solution, the water becomes undersaturated
with respect to dolomite. In response, more dolomite
dissolves and more dissolved calcium and magnesium
are available for ion exchange. As cation exchange and
dolomite dissolution continue at depth in the confined
aquifer, the pH gradually increases. Along longer flow
paths at depth and in the confined part of the aquifer
(Figure 8), where carbon dioxide is limited, this process
can elevate the pH to greater than 8.5 - the pH value at
which arsenic is expected to begin desorbing from iron-
oxide mineral coatings (Figure 10).
Cf.
UJ
o Sample from Central Oklahoma
aquifer
* Sample from Central Oklahoma
aquifer in Cleveland County
- - EPA (1 986) MCL for arsenic in
drinking water
drinking water
2!
li
!
j..t.*t...A
ป
; * * **
* 0
ฐ ซ: .
. '> ฐ
. I I I : ! , I
~ 50
Q
5 2ฐ
O 10
UJ 0
tO 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.C
< FIELD pH, IN STANDARD UNITS
Figure 10. Relation between dissolved arsenic
concentration and pH for wells in the
Central Oklahoma aquifer [MCL, Maximum
Contaminant Level].
Multiple lines of evidence support the Central Oklahoma
aquifer conceptual model. Though ground-water pH in
the aquifer ranges from about 6.0 to 9.6 (Schlottmann
et al., 1998), most elevated arsenic concentrations occur
in water with pH greater than 8.5 standard units (Figure
10). Because longer flow paths and greater quantities
of clay-rich rocks (which participate in ion-exchange)
tend to occur in deeper parts of the aquifer (Figure 8),
a strong relation exists between well depth and arsenic
concentration (Becker, 2006). Because longer flow paths
and clay-rich rocks tend to occur in the confined part of
the aquifer (Figure 8), a strong relation exists between
well location and arsenic concentration (Figure 2).
Spatial Variability of Water Quality in the
Deep Aquifer System
Because water chemistry changes along flow paths, the
aquifer area can be divided into different water-type
regions that are consistent with the Central Oklahoma
aquifer conceptual model. For wells greater than
300 feet deep, Parkhurst et al. (1994) realized that the
major-ion composition of water near the potentiometric
high (area of greatest recharge) was dominated by
the products of dolomite dissolution. The calcium-
magnesium-bicarbonate water type in that area is
characteristic of relatively recent recharge water that
has not been substantially altered by cation-exchange
reactions (Figure 9). Water in that area is hard and has
a near-neutral pH. Along the southern flow path under
the confining unit, the character of water changes to a
sodium-bicarbonate water type around northwestern
Norman as sodium in clays is exchanged for calcium
and magnesium in ground water (Figure 9). Water in this
region is soft and has a pH that approaches 8.5 standard
units. Farther south and west under the confining unit,
the water is dominated by sodium-bicarbonate-sulfate
(Figure 9). This change in chemistry is thought to reflect
the influence of dissolution of sulfate-bearing rocks in
the overlying Hennessey Group. In regions with this
water type, cation exchange has removed nearly all
calcium and magnesium from the water. This water is
soft and is likely to have a pH greater than 8.5 standard
units. Sodium-bicarbonate and sodium-bicarbonate-
sulfate water types are closely associated with elevated
arsenic concentrations in the Central Oklahoma aquifer.
Studies by the USGS have established that arsenic in the
aqueous phase is not evenly distributed with depth in
some parts of the Central Oklahoma aquifer (Parkhurst
etal., 1996; Schlottmann and Funkhouser, 1991;
Schlottmann et al., 1998). Aqueous concentrations of
arsenic (as well as the geochemically related oxyanions
of chromium, selenium, and uranium) are sometimes
only elevated in one or two zones in a well. Schlottmann
et al. (1998) and Schlottmann and Funkhouser (1991)
measured aqueous arsenic (65 ug/L), selenium (380
ug/L), and uranium (318 ug/L) concentrations exceeding
the MCLs (10, 50, and 30 ug/L, respectively) in a deep
sandstone zone from a test hole near Edmond, Oklahoma
(Figure 1); all other sampled zones in the same test hole
had concentrations that were less than the MCLs. If
zones with elevated trace element concentrations can be
identified and sealed off from production, concentrations
measured at the well head may be decreased to meet
drinking-water regulations.
-------
4.0
Approach and Methods
Selection of Wells for Investigation
The data compiled in Figure 11 represent well-head
arsenic concentrations of active Norman wells. Through
2003, nearly two thirds of the wells in the Norman well
field had produced water with arsenic concentration
greater than 10 ug/L (Table 1; Figure 11). The total
number of available water samples from each well is
listed in black near the top of Figure 11, and the number
of censored (nondetected) analysis values is represented
by a blue number at the bottom of Figure 11. These
well-head samples were analyzed by several different
laboratories with reporting levels ranging from 0.2 to
15 ug/L. Because some censored values had a practical
quantitation limit greater than or equal to 10, the median
value of detections (excluding the censored values)
was selected to represent central tendency of well-head
arsenic concentrations.
A consensus decision was made to assess water quality
with depth in 11 Norman wells (Table 1, Figures 11-
12) in meetings with officials representing the City
of Norman, EPA, and USGS. Several factors were
considered for well selection including median arsenic
concentration, well production rate, well age, and
well location in the well field. The best candidates for
successful remediation were considered to be those wells
that had (1) marginal well-head arsenic concentrations
(near 10 ug/L), (2) wide variation in well-head arsenic
concentrations, and (3) high water-production rates
(greater than 200 gallons per minute). These wells are
most likely to benefit from isolation of a single, high-
arsenic zone and are the least likely to suffer from loss of
production from that zone. Because remediation of older
wells nearing life-expectancy was not cost-effective,
more recently constructed wells were selected over older
wells. Some wells, such as Well 07, were given more
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EXPLANATION
Historic well-head
arsenic sample,
1984-2001
- Median concentration
of historic well-head
arsenic detections
3 Number of historic
samples
(1) Number of historic
samples with
nondetections
05 Sampled wells, this study
... EPA (1986) MCL for
arsenic in drinking water
... EPA (2001) MCL for
arsenic in drinking water
ซ Well yield, in gallons
per minute, from Norman
files (see table 1)
01 02 03 04 05 06 07 08 10 11 12 13 14 15 16 18 19 20 21 23 24 25 31 32 33 34 35 36 37 38 39 40
CITY OF NORMAN WELLS
Figure 11. Well-head concentrations, median values, and maximum contaminant levels for arsenic in the Norman well
field, 2003.
-------
consideration because those wells were located in parts
of the aquifer not represented by other selected wells
(Figure 12). One Well (23) with unusually high arsenic
concentration was selected for a comparison of well-
sampling methods.
Historical well-head arsenic concentrations were useful
for identifying wells that might have potential for
rehabilitation by well modification. Some wells (for
example Well 05, Figure 11) showed large variation in
arsenic concentration over time. Variation in reported
arsenic concentrations over time indicates that a well
has differences in water quality with depth. Assuming
that data were accurately reported and that water
chemistry of contributing zones has remained relatively
constant over the life of the well, there must be at least
one zone in the well that produces water with arsenic
concentrations equal to or greater than the maximum
detected value (for example, 150 ug/L for Well 05).
Likewise, there must be at least one zone that produces
water with arsenic concentrations equal to or less than
the minimum detected value (2 ug/L for Well 05). The
difference between the maximum and minimum detected
concentrations, therefore, gives an indication of the
range in water quality to expect if depth-dependent or
zone-specific samples were collected. If all well-head
samples are nearly equal in arsenic concentration over
time (for example Well 25, Figure 11), there may be little
variation in water quality with depth and little potential
for successful remediation by well modification.
The temporal variability in well-head arsenic
concentrations, from a compliance standpoint, can be
problematic for a public water-supply system. Some
wells, which may have always tested around 5 ug/L
arsenic, may suddenly test slightly greater than 10 ug/L
and become noncompliant. In remediation attempts,
the only way to increase the likelihood that well-head
arsenic concentrations will never exceed 10 ug/L is to
exclude from production all zones that contribute arsenic
at concentrations greater than 10 ug/L.
Remediation Options
This report examines two potentially reasonable
remediation options which involve well modification.
The ultimate goal of both options is to decrease the
proportion of flow supplied by contaminated zones
and increase the proportion of flow supplied by
uncontaminated zones.
The simplest and least costly remediation option is to
move the pump intake to a new location and/or decrease
the capacity of the pump. If the pump intake is moved
farther from a contaminated zone, the well may produce
a lesser proportion of water from the contaminated zone
(Ground Water Protection Council, 2005). This strategy
is reversible, minimizes potential loss of production, and
involves minimal down time for the well. This method,
however, may provide only a temporary remediation
solution because well-head contaminant concentrations
may fluctuate with seasonal or prolonged changes in
97ฐ3ffW 97ฐ29W 97ฐ28'W 97ฐ27W 97ฐ261W 97ฐ251W 97ฐ241W 97ฐ231W 97ฐ22W
EXPLANATION
. Water
Geologic Unit
CD Alluvium
I I Terrace
CD Hennessey Group
(confining unit)
CZI Garter Sandstone
Norman roads
Rivers and streams
Norman boundary
TH ^ Norman arsenic test hole
20 Norman wells and number
IgO Sampled Norman wells and number
0 0.5 1
I I 'I '
0 0.5 1
2 MILES
KILOMETERS
HvdmalBDhv from Oklahoma Water R
Figure 12. Selected wells and surficial geology of the Norman well field, 2003.
-------
aquifer water levels. Over time, the well could produce
an increasingly greater proportion of flow from the
contaminated zone and subsequently degrade well-head
water quality.
Another well-head remediation strategy is zonal
isolation, which involves plugging an arsenic
contributing zone. This strategy is designed to ensure
that a known contaminated zone will no longer
contribute to well production. This technique is well
suited for use in open-hole wells and gun-perforated
wells with a cement annulus. This strategy also could
be applied in screened wells, but a gravel-pack annulus
makes complete isolation more difficult. In aquifers
composed of incompetent rocks, gun-perforated
completions are preferred for this technique because
the cement annulus prohibits flow behind the casing.
Zonal isolation also is best suited for use in aquifers
where contributing zones are hydraulically separated by
thick, laterally continuous, and relatively impermeable
units. The Central Oklahoma aquifer was well suited for
the zonal-isolation strategy because a large number of
marginal wells have gun-perforated completions, and
producing sandstone zones are commonly separated
or compartmentalized by thick mudstones. However,
intervening mudstones may not be laterally continuous
or impermeable near the well.
Methods of Hydraulic Data Collection
Two types of data collection methods were used in this
study to record changes in well yield and water quality
as a function of depth in Norman municipal wells.
Impeller-flowmeter logging (Leve, 1964) and straddle-
packer testing (Hess, 1993) were applied only at Norman
Well 23. An alternate method, the USGS combined
well-bore flow and depth-dependent water sampler
(USGS well profiler; U.S. patent numbers 6,131,451
and 6,164,127; Izbicki et al., 1999), was applied at all
Norman wells investigated in this study.
Flowmeter Logging and Straddle-packer
Testing
A flowmeter is often used to identify producing zones
and quantify production from individual zones in wells;
a variety of types of down-hole flowmeters are available
to obtain these data. An impeller (spinner) flowmeter
is a wire-line tool consisting of a small impeller that
is free to rotate around a vertically oriented axis. As
the tool is slowly lowered or raised in a pumping well,
the flowmeter records the vertical component of water
velocity through the cross-sectional area of the well and
produces a continuous log of flow contribution with
depth. The flow-contribution log describes the proportion
of well yield supplied by each producing zone. The
impeller flowmeter is capable of detecting velocities
as small as 0.2 foot per second (ft/s) (Hess, 1982), but
the tool is sensitive to changes in cross-sectional area
with depth in the well, which can be caused by scale
buildup, centralizers, or damaged casing. When present,
these features can cause large fluctuations in velocity,
and, along with the effects of turbulent flow in the well,
can make the impeller-flowmeter velocity profile noisy
and difficult to interpret. When conducting an impeller-
flowmeter test, if the pump is set near the bottom of
the well, the pump must be raised or replaced with a
temporary pump set just below the pumping water level.
This configuration reduces the possibility of damaging
the tool or getting the tool lodged in the well. If the
location of the pump during testing is different from the
location of the pump during production, though, the flow
dynamics created during testing also can be different
from the flow dynamics during production.
Water quality with depth is most commonly recorded
using packer tests. Inflatable straddle-packer tests are
the traditional method used to obtain depth-dependent
samples in cement-annulus, gun-perforated water wells.
Straddle packers are high-pressure, rubber bladders
separated by a length of slotted pipe (Figure 13). The
packers are adjustable to any separation width and can be
used to test zones of different thickness. In preparation
for packer testing, the pump, column pipe, and all other
equipment must be removed from the well. The casing
wall should be brushed to create a smooth surface on
which to complete the packer seal. When a producing
zone has been selected for testing, the packer spacing
is adjusted to match the thickness of the target zone
and the packers are lowered to the desired depth by
adding known lengths of pipe. Using compressed gas
or pressurized fluid supplied by a line at the surface,
the bottom packer is inflated just below the target zone
and the top packer is inflated just above the target zone.
When both packers are inflated and properly sealed
against the casing, the water level inside the packer
string equilibrates to the head of the isolated zone. A
low-capacity (5 gallons per minute) submersible pump is
connected to a small diameter conductor pipe and placed
inside the pipe supporting the packers (Figure 13). The
pump is lowered to a depth that is well below the static
water level of the isolated zone. When the pump is
activated, water from the isolated zone flows into the
slotted pipe separating the packers, into the submersible
pump, and through the conductor pipe to the surface
(Figure 13). After purging for some time, field tests can
be made and laboratory water samples can be collected
from the discharge hose. For packer testing, a cement-
filled and perforated annular space is more desirable than
a gravel-filled annular space because the cement-filled
annulus prohibits intra-annular communication between
permeable zones.
-------
Perforations
Inflated packer
o o
0 0
Pump intake (on
conductor pipe inside
'packer string pipe)
Sandstone
Mudstone
Sampled
zone
' Slotted pipe
Packer string
-Steel casing
~ Cement annulus
Figure 13. Apparatus used in straddle-packer testing of
Norman Well 23.
When the results of impeller-flowmeter logging and
packer testing are combined, the data may be used to
determine which zones have the greatest influence on
water quality at the well head. This information, in turn,
guides the selection of appropriate well rehabilitation
techniques.
USGS Well Profiler
Though flowmeter logs and packer tests are the
traditional methods of depth-dependent flow and water-
quality data collection, these methods do not always
provide the most useful and representative information
on well properties during production. Preparation for
using these methods also is time consuming, invasive,
and expensive. As an alternate method, the USGS has
used a combined well-bore flow and depth-dependent
water sampler, referred to as the USGS well profiler, to
quantify the contribution of water from perforated or
screened zones and to collect samples at various depths
in a pumping well (Izbicki et al., 1999). The USGS well-
profiler method, as compared to traditional methods,
can be considerably less expensive and requires less
down-time of the well. In terms of data quality, the
most important advantages of the USGS well profiler
are that all data collection is performed under true
production conditions and that the technique requires
minimal modification to the well. The methods described
document the adaptation and application of the USGS
well profiler to the style of well construction common in
the Norman well field.
The USGS well profiler is a slim, high-pressure,
multipurpose hose that can be raised and lowered
between the pump column and well casing (or borehole
wall) by using a motorized hose reel (Figure 14a). A line
counter at the surface (Figure 14b) reports the depth of
the hose outlet and electrical-tape markings (Figure 14c)
on the multipurpose hose are used to confirm counter
readings. The hose outlet is equipped with a 0.25-inch
pressure-activated, in-line check valve. A 0.25-inch
diameter, 35-foot long, stainless-steel cable weight is
attached below the check valve to keep the hose hanging
straight in the well (Figure 14b). A threaded coupler is
welded to the cable weight and small drilled openings in
the coupler allow dye tracer solution and sample water to
pass in and out of the hose.
A machine-slotted polyvinyl-chloride (PVC) access
tube was installed in most selected wells to facilitate
access with the USGS well profiler. Obstructions and
irregularities in the borehole or casing wall and pump
column, such as scale, can impede the movement
of the sampling hose in and out of the well. Other
obstructions include electrical cables, steel pipe
joints, banding material, pump shrouds, pump bowls,
centralizers, airlines, and lost tools (Figure 14f). Nearly
all obstructions can be bypassed by pulling the pump
column and reinstalling the column with a 1.25-inch
diameter, 0.375-inch slotted PVC access tube, which is
banded to the column pipe every 20 feet (Figure 14g).
In a few wells, the access tube was placed next to the
electrical cable (Figure 14g), but the access tube usually
was placed opposite the electrical cable (Figure 15).
The bottom end of the access tube was open, cut at an
angle, and attached just above the pump intake. Only the
submerged part of the access tube was slotted; the upper
part of the access tube was blank 1.25-inch PVC.
-------
Figure 14. Photographs of the USGS well profiler (A) and related equipment including line counter and stainless-steel
cable weight (B), multipurpose hose with depth marking (C), Teflon-lined sample hose attachment (D), and
field fluorometer and laptop for data logging (E). Photograph F shows the multipurpose hose stuck between
a stainless-steel band and the pump column. Photograph G shows the solution to this problem; most well
profiler data were collected inside a slotted PVC access tube (arrow), which was banded to the pump
ihs by Jerrod Smith, U.S.
-------
Above pump intake
Unknown thickness
of well scale
Electrical cable
R0,B=0.75 inch
Well profiler hose
Area above pump = A,BO,,=it((r0J12)2-(ru/12)2-(rc,B/12)2)
Below pump intake
Unknown thickness
of well scale
above
EXPLANATION
cross-sectional area of the well
above the pump intake
cross-sectional area of the well
below the pump intake
inner radius of the casing
Abel
rcas
r
outer radius of the pump
column pipe
radius of the electrical cable
PVC polyvinyl chloride
Area below pump = ABBBW=jt(r0J12)2
NOT TO SCALE
Figure 15. Generalized horizontal well cross sections
and unit area computations above and below
the pump intake in wells with a 10-inch
casing and 4-inch pump column.
With the exception of Wells 23 and 33, wells in this
study were equipped with a slotted PVC access tube in
which all tests were performed. All tests at Well 23 were
conducted without a PVC access tube. In Well 33, only
depth-dependent sampling was conducted inside the
access tube. The well-profiler hose became stuck in the
wells repeatedly at the beginning of this investigation
(Figure 14f), but few problems were encountered after
installation of the PVC access tube in the sampled
wells. Only two problems occurred during tests inside
the access tube. One problem was caused by incorrect
placement of the tube outlet relative to the pump.
The second problem occurred when the cable weight
disconnected prematurely, fell down the access tube, and
broke through the PVC tube. The weight became lodged
in the PVC tube and blocked access into the well.
Tracer-pulse Velocity Logging
Prior to sampling, a velocity profile is constructed to
determine the percentage of the total well discharge
coming from each contributing depth interval (which
may include multiple zones or a part of a zone). To
obtain the velocity profile, the multipurpose hose is
filled with a dilute, nontoxic, Rhodamine WT dye
solution. A brass check valve with a pressure threshold
of about 350 pounds per square inch (psi) is attached to
the bottom of the multipurpose hose. The check valve
keeps dye solution from exiting the hose prematurely.
The Rhodamine-filled hose is lowered to the bottom of
a pumping well and a pulse of dye solution is injected
into the water column using a high-pressure pump at
the surface. The pulse travels to the pump intake at the
same velocity as water traveling in the well borehole
or casing. A small portion of the discharge from the
pumping well is routed through a field fluorometer
(Turner Designs model 10-AU1), which measures dye
concentration (in micrograms per liter) at one-second
intervals (Figure 14e). When the injected dye pulse is
first detected at the surface, the traveltime in seconds
is recorded for the given depth. Then the hose is raised
3 to 5 feet and another pulse of dye solution is injected
into the well. When the recorded traveltimes are plotted
versus depth and combined with ancillary information
such as well diameter, the following can be inferred:
1. the depth of the pump intake (minimum
traveltime),
2. an estimate of total well yield,
3. changes in water velocity in the well,
4. the approximate depths of contributing intervals,
5. the relative amounts of water produced by these
intervals, and
6. the pumping water level.
To interpret the data obtained from a tracer-pulse
velocity profile, several assumptions must be made
regarding conditions in the pumping well. Velocities
(slopes) on the tracer-pulse profile should always
increase in the direction of the pump. In addition,
laminar pipe flow must be assumed to occur in these
wells, but estimates of the dimensionless Reynolds
number (Chow, 1959) revealed that laminar flow is
disrupted at velocities as small as 0.3 ft/s, and turbulent
flow is likely to be present at velocities greater than
about 1 ft/s. The velocity resolution of the tracer-pulse
technique appears to be about 0.1 ft/s in Norman wells.
Assumptions of the tracer-pulse method:
1. Velocities inside and outside the PVC access tube
are equal at a given depth.
2. Velocities (and zonal contribution rates) do not
change appreciably with time during testing.
3. No sustained changes occur in well cross-
sectional area either above or below the pump
intake.
1 Any use of trade, product, or firm names is for descriptive
purposes only and does not imply endorsement by the U.S.
Government
-------
4. Flow in the well is uniform, laminar, and purely
vertical.
5. During production, water in the well never flows
back out into the formation.
6. Velocity can never decrease in the direction of the
pump.
7. Changes in well-bore velocity are proportional to
changes in flow rate in the well.
Estimates of Total Well Yield
Tracer-pulse data near the pump intake allow for
independent estimates of total well yield, or well-head
discharge. This value is necessary to convert estimated
zonal flow contribution (in percent) to a zonal discharge
(in gallons per minute). Though well-head flowmeters
were present at most of the wells in the Norman well
field, the flowmeters were installed to read the flow rate
only when the well was pumping into the distribution
line. All dye-injection tests were performed while the
well was pumping to waste (not into the distribution
line), therefore, the well yield reported by the well-head
flowmeter was not used in any calculations of zonal
flow contribution. If the size of the pump column pipe
is known, the well yield can be estimated using tracer
traveltime data. The depth (in feet) of the minimum
recorded traveltime, which marks the pump intake, can
be divided by the minimum traveltime (in seconds)
to compute the velocity (in feet per second) of water
traveling through the pump column to the surface. Well
scale thickness, which can reduce the theoretical cross-
sectional area inside the pump-column pipe, was not
routinely measured but was assumed to be no greater
than 0.125 inch ~ the maximum scale thickness observed
on the outside of any drop pipe. More commonly, well-
scale thickness was about 0.1 inch. Estimated total well
yields were listed with a confidence interval to reflect
uncertainty caused by unknown well-scale thickness.
The bounds of the confidence interval were computed as:
v * 448.8
(with 0.125-inch scale thickness)
Q . = v , * 7i(r .
^mm col v mirr
Q =v ,*7i(r )2* 448.8
^max col x max'
(with 0.000-inch scale thickness)
where
Q is the well yield in gallons per minute,
vcol is the estimated velocity of water in the pump
column in feet per second,
r is the inner radius of the column pipe in feet, and
448.8 is the conversion factor from cubic feet per
second to gallons per minute.
The difference between the minimum (min) and
maximum (max) computed flow rate in Norman wells
ranged from about 90 gallons per minute to 40 gallons
per minute. The reported yield is the average of Qmax and
Qmm, and the reported confidence interval is equal to one
half the difference of Qmax and Qmm.
Techniques for Determining Flow Contribution by
Open Intervals
A graphical approach was used to incrementally
determine flow contribution from open (perforated
or screened) intervals. This approach was necessary
because changes in flow velocities are small compared
to noise associated with the tracer-pulse technique.
First, the hose depth and raw traveltime data were
plotted on a large format graph similar to Figures 16-
17. Envelope-fit lines were drawn across sections of the
data that expressed linear trends. The slope of these lines
(change in depth divided by the change in traveltime)
represents the vertical component of water velocity in
the well across the given depth interval. Increases in
slope (velocity) are proportional to flow contribution by
open intervals.
Two examples of traveltime profiles are presented
in Figures 16-17. Slope breaks can be identified in
Figure 16 by moving a straight edge along the traveltime
profile. Changes in slope occur at depths of 430, 450,
500, 530, and 565 feet in data from April 2004 in Well
23 (Figure 16). Slope breaks in Well 15 are more subtle
but were identified in the same way (Figure 17). Each
change in slope is attributed to the nearest open interval
in the direction opposite the pump. The total flow gained
over each change in slope was computed using the
equation:
Q =(v-v,)A
^-sained ^-2 \'
where
v2 is the greater vertical velocity,
YJ is the lesser vertical velocity, and
A is the cross-sectional area of the well.
For comparison between intervals or zones, flow
contribution from each interval or zone is reported as a
percentage of the well yield.
The cross-sectional area was assumed to be constant
above and below the pump intake, except in Well 23,
which had a 5-inch-diameter pump on a 4-inch-diameter
pump column. For simplification of calculations, the
pump column is assumed to end at the pump intake. In
reality, the submersible pump motor extends another 3 to
5 feet below the intake. This simplification is acceptable
because the length of the motor is comparable to the
method depth resolution of 3 feet. The computation of
cross-sectional area below the pump intake (Figure 15) is
relatively simple and robust using the equation:
A, =7i(r /12)2
naelow v cas '
-------
Natural gamma-ray log
380 and perforation record
400
420
UJ
O 430
ฃ 440
W 450
460
470
in 490
UJ 500
UJ
"- 510
"~- 520
ฃ 530
Q 540
550
560
570
580
590
600
D March 30, 2004
ซ April 26, 2004
T Pumping water level
A Pump Intake depth
I Perforated interval
8\ ง 8 ง g
\ 5-inch diameter pump
S 8
8 S g
TRAVELTIME, IN SECONDS
Figure 16. Traveltimes determined by tracer-pulse method in Norman Well 23 in 2004.
430
440
450
460
470
480
490
500
510
520
530
540
550
560
570
580
590
600
610
620
630
640
650
660
670
680
Natural gamma-ray log
and perforation record
0 -*
f
^ December 28, 2004
^ Pumping water level
A Pump intake depth
I Perforated interval
OOOOOOOOOOOOOOOOOOOOpOpppppppppOppppppppp
TRAVELTIME, IN SECONDS
Figure 17. Traveltimes determined by tracer-pulse method in Norman Well 15 in 2004.
-------
where
A, , is the cross-sectional area of the well below the
Hjelow
pump intake in square feet and
rcas is the inner radius of the casing in inches.
The computation of cross-sectional area above the pump
intake is more complex because of the presence of the
pump column and attachments (Figure 15). The area
above the pump intake can be approximated using the
equation:
A,, =7i((r /12)2-(r ,,^, ,, ,,
above vv cas ' v col ' v cab
where
Aabove is the cross-sectional area of the well above the
pump intake in square feet,
rcas is the inner radius of the casing in inches,
rcol is the outer radius of the pump column pipe in
inches, and
rcab is the radius of the electrical cable in inches.
When this equation was applied to computations of
flow rate, the flow rates were unreasonably high. This
discrepancy was probably because the effective cross-
sectional area was much less than the true area. The
effective cross-sectional area is the remaining area after
the theoretical cross-sectional area has been reduced by
scale deposits and dead spaces such as eddies.
An empirical approach was used to estimate the effective
cross-sectional area above the pump intake in wells
with typical construction specifications (4-inch pump
column in a 10-inch casing). The effective area was
computed using the maximum estimate of well yield, the
flow rate below the pump intake, and the tracer-pulse
velocity determined just above the pump intake using the
equation:
A,, =(Q -A, ปv,, )/v,
above v ^-max oelow * below7 abov
above
where
Aabove is the cross-sectional area of the well above the
pump,
Abelow is the cross-sectional area of the well below the
pump,
Q is the maximum estimate of well yield from
^-max >
tracer-pulse data,
vbelow is the maximum velocity measured below the
pump intake, and
v, is the maximum velocity measured above the
above >
pump intake.
Calculations of effective area in Norman wells with
typical construction (4-inch pump column in a 10-inch
casing) ranged from 0.14 to 0.36 square foot, with an
average area of 0.21 square foot. The average area of
0.21 square foot was applied to computations for all
wells. The theoretical cross-sectional area for a typical
Norman well was about 0.42 square foot. The difference
between the theoretical and effective cross-sectional
areas is likely to diminish as the casing diameter
increases, the pump column diameter decreases, or the
water velocity decreases.
The average area of 0.21 square foot also was applied
to Wells 05 (initial pump depth), 07, 13, 23, 33, and 36
(initial pump depth) in which no traveltime data were
collected below the pump. When the flow above the
pump exceeded the maximum estimate of well yield,
open intervals below the pump were not quantifiable
and were labeled (NQ). For some of these calculations,
however, the flow above the pump intake was
considerably less than the maximum estimate of well
yield. In these cases, the difference in flow was assumed
to originate from below the pump intake.
Wells 15 and 31 had non-typical construction; Well 15
had a 5-inch pump column and Well 31 had a 12-inch
casing. For these wells, the same procedure was used
to determine the cross-sectional area above the pump,
but the results were not averaged with wells of similar
construction. Effective areas computed for Wells 15 and
31 were 0.27 and 0.41 square feet, respectively.
Cross-sectional Area Computations
For wells with traveltime data points above and below
the pump intake (see example, Figure 17), computations
began with a determination of the proportions of water
coming from above and below the pump. The accuracy
of these computations depends on the accuracy of
computed cross-sectional areas and is, therefore, prone
to error. The flow gained over each open interval was
computed as a proportion of the total flow coming
from above or below the pump. No data points were
obtained below the pump in some wells. In these cases,
the total flow coming from below the pump could not
be determined from velocity measurements. Also, open
intervals within a few feet of the pump intake could not
be analyzed for flow contribution using the tracer-pulse
method. When the pump intake is set in an open interval,
water from the interval is pulled into the intake without
traveling vertically. When the pump intake is set near an
open interval, there may not be enough traveltime data
points across the interval to determine a velocity. When
flow contribution could not be quantified, the interval
was marked NQ. The percentages of flow contribution
from other open intervals were determined as if the
unquantifiable interval produced no water.
Hose Stretch
Because the multipurpose hose has elastic properties,
estimation and compensation for line stretch was
necessary. The stretch calibration technique compared an
-------
air-line-determined depth reading with the line-counter
reading and computed the difference in terms of percent
stretch. The percent stretch was added to each line
counter reading to arrive at a corrected depth for the hose
intake. The first estimate of stretch was made before
the 11-well investigation (Figure 4), when the hose
was relatively new. A three percent stretch factor was
estimated at that time. As the hose made numerous trips
in and out of the wells during preliminary tests, some
temporary elastic stretch was converted to permanent
inelastic stretch, especially on a few occasions when
the hose became stuck in the well. A second estimate of
stretch was conducted late in the 11-well investigation
and yielded a factor of two percent. A two percent stretch
correction factor was applied to all tests and all reported
depths are stretch-corrected depths below land surface.
PVC Access Tube
The effect of the access tube on the quality of well-
profiler data is unknown because no repeat tests were
performed in a well before and after access tube
installation. The ability to freely move through the
water column certainly increased the precision of depth
measurements and, subsequently, water velocities
obtained by the tracer-pulse method. A few recorded dye
pulses from above the pump in one well, however, were
irregular with dual peaks. The separation between peaks
increased with distance from the pump intake. These
observations indicated that there may be a difference
between water velocities inside and outside the PVC
access tube.
Depth-dependent Sampling
After contributing intervals are identified, the
multipurpose hose is drained and flushed of dye solution,
and a Teflonฎ-lined sample hose with a stainless-steel
braided cover is attached to the end of the multipurpose
hose (Figure 14d). A stainless-steel check valve with
a pressure threshold of 3 psi separates the two hoses
and prevents contamination of the sample hose by any
residual dye solution in the multipurpose hose. An
identical check valve is attached to the bottom of the
sample hose (Figure 18). Both hoses are filled with
compressed nitrogen gas to a pressure greater than the
Multi-
purpose\
from multi-purpose
B
PI Pressurized
sample hose Surface valve
Is lowered to open to
I [sampledepth atmosphere
V
50-foot,
- Teflon-
lined,
sample
hose
attachment
Nitrogen-
filled hose.
to 250 psi
ft 0
Hydrostatic
pressure at sample
depth < 250 psi
At the si
hose attachment Is
multi-purpose hose
pressure at
sample depth
is greater than
the pressure In
the hose
Surface valve
closed to
r^-*~>i
V.*
A
, Sample hose
Is returned to
1 'surface
sur
Hydrostatic pressure of
water in the hose keeps
NOT TO SCALE
Sample water Is
expelled with low-
pressure nitrogen
o
O
To water-quality
sampling apparatus
Figure 18. Procedure for depth-dependent sampling with the USGS well profiler. Green, white, and blue arrows
indicate movement of the hose, nitrogen pressure, and water pressure, respectively. Green circles indicate
open check valves and red crossed circles indicate closed check valves [psi, pounds per square inch].
-------
maximum possible hydrostatic pressure at the bottom of
the well (250 psi was used in all Norman wells). Because
of the presence of in-line check valves, the system must
be pressurized from the bottom of the sample hose.
The surface end of the hose is equipped with a pressure
gauge for reading the system pressure and a manually
controlled release valve for venting the hose. When the
system pressure reaches the desired value, the nitrogen
pressure source is detached and the pressurized hose is
lowered to the desired sample depth (Figure 18a). In
cased wells where the depths of openings are known, the
sample-hose intake is placed to limit bias by local inputs
of water and allow for the most complete mixing of
water from contributing intervals.
When the sample depth is reached, samples are collected
by opening the manual valve on the surface end of
the hose. As the hose depressurizes, the hydrostatic
pressure of the water column in the well exceeds the
pressure inside the hose (Figure 18b). The in-line check
valves open and sample water fills the hose to (about)
the pumping water level. When the sample hose stops
venting at the surface, the pressures have equilibrated
and the hose is full. The manual valve at the surface is
closed and the water-filled hose is reeled to the surface
(Figure 18c). The pressure of the water column inside
the hose is great enough to close the in-line check
valves during hose retrieval. Once at the surface, the
sample-hose attachment (including check valves) is
disconnected from the multipurpose hose and attached
to the sampling apparatus (Figure 18d). Compressed
nitrogen is used to force the sample water out of the
sample hose and into bottles. Though excess sample
water may partially fill the multipurpose hose, this water
is not suitable for analysis and must be discharged with
compressed nitrogen between samples.
Each sample collected with the well profiler represents
conditions at a discrete depth in the pumping well,
not a specific hydrogeologic zone in the formation.
The well profiler sample is a mixture of water from
several contributing zones, which can be several feet
away from the sample depth. Because the proportion
of water produced from each zone was estimated using
the tracer-pulse technique, a mass balance approach
could be used to estimate constituent concentrations in
each zone. However, the depth-dependent water-quality
data are more appropriately used to draw qualitative
comparisons between zones. This comparison can be
performed without knowing how much water is being
produced by each zone. For example, the concentration
data could be used to determine which zones produce
water with elevated concentrations of arsenic and
which zones produce water that is relatively free of
arsenic contamination. If a sample at depth A has an
arsenic concentration of 3 ug/L, and an adjacent sample
(in the direction of flow) at depth B has an arsenic
concentration of 20 ug/L, there is likely a zone between
sample depth A and B that is contributing water with
an arsenic concentration greater than 20 ug/L. The
likelihood of identifying a single contaminated zone
depends on the spacing and locations of depth-dependent
samples collected relative to the spacing and locations of
producing zones.
The sample-hose attachment used has an inner diameter
of 13/32 inch and is 50 feet in length. These dimensions
contain a storage volume of about 0.33 gallon
(1.25 liters). Because the total sample volume is limited,
every effort was made to conserve water and fill bottles
in a timely, organized manner. After a field rinse of
the sampling apparatus, field measurements of water
properties were collected, followed by collection of
unfiltered samples and then filtered samples (Table 3).
The more sensitive filtered samples were collected
last because the last water to enter the sample-hose
attachment during sample collection is the last water
to be expelled from the sample-hose attachment during
bottling. This water has a lesser chance of contamination
from the multipurpose hose because any contamination
from the multipurpose hose should be flushed from the
apparatus by previous steps in the sampling process.
Table 3. Summary of sample water use and analysis
types in order of collection
Volume
(milli-
liters)
200
250
250
40
40
60
40
40
40
960
Bottle type
--
--
polyethylene
amber glass
amber glass
glass
amber glass
amber glass
amber glass
Analysis
order
field water
properties*
rinse water
alkalinity
major
anions
nutrients
isotopic
ratios
carbon
arsenic
speciation
metals
Preserva-
tive
--
--
-
--
H2S04
--
--
--
HN03
Filtra-
tion
no**
no
no
no
no
no
yes
yes
yes
Sample hose volume = 1,250 milliliters
* includes specific conductance, pH, water temperature,
turbidity, dissolved oxygen concentration, and iron
speciation.
"Only samples for iron speciation were filtered; all other field
measurements used unfiltered water.
-------
Decontamination Procedures
Laboratory decontamination of sampling equipment
was performed using USGS standard methods (Wilde et
al., 1998). The same procedures were applied to sample
hoses and fittings with one exception. The sample-hose
attachment is Teflon-lined and would normally be rinsed
with a five percent hydrochloric-acid solution. This
step was not applied during the 11-well investigation
of water-quality changes with depth (Figure 4) because
the rinse would damage the permanently attached
stainless-steel fittings. For the two-well investigation of
arsenic remediation techniques (Figure 4), the laboratory
decontamination for the sample-hose attachment did
include a hydrochloric acid rinse that bypassed the
stainless-steel fittings. In the field, the sample hose
was evacuated with compressed nitrogen between each
sample until no water was visible exiting the hose. The
entire sampling apparatus was cleaned in the laboratory
before moving to another well.
Quality-assurance Procedures
Quality assurance was evaluated using blanks (4),
replicates (7), and laboratory duplicates (84). Replicate
and duplicate analysis values are listed after each paired
environmental sample in the appendix tables. Replicates
and laboratory duplicates were mostly consistent with
paired environmental samples. About 78 percent of all
replicate measurements had relative percent differences
less than 5 percent. Replicate types included repeat
sampling, in which new sample water was collected from
the same depth, and repeat bottling, in which two bottles
were filled from the same parent sample volume. The
repeat bottling replicate data showed that contamination
from the multipurpose hose (which is attached to only
one end of the sample hose) was not a problem. The
repeat sampling replicate data showed that depth-
dependent sampling was repeatable in Norman wells.
Major-ion concentrations were consistent in replicate
data, but some trace-element concentrations occasionally
showed large variation in replicate data. Aluminum,
barium, boron, and titanium each had multiple replicate
values with relative percent differences greater than
ten percent. Among measurements of field water
properties, turbidity and field iron speciation each had
multiple replicate values with relative percent differences
greater than ten percent. Laboratory duplicates, which
were created by splitting the environmental samples,
were part of the standard procedures of the analyzing
laboratory. These duplicates were used to assess
repeatability and precision of laboratory methods. No
problems were identified in visual comparisons of
environmental sample concentrations and laboratory
duplicate concentrations.
Several constituents (mostly trace elements) were
detected in two field blanks, but concentrations were
usually much less than the concentrations detected
in typical environmental samples. Nitrate, barium,
boron, strontium, and dissolved organic carbon were
detected in blanks at concentrations comparable to or
exceeding concentrations detected in environmental
samples. The contamination is most likely the result of
a documented change in the bottling procedures used by
the blank water manufacturer. Low-level detections were
documented in OmniSolv organic blank water beginning
with lot number 44328 (USGS National Water Quality
Laboratory lot number 80501), which was used in this
study. This lot number and water type was investigated
by processing source-water blanks and was discontinued
from use as an inorganic blank water in June 2006, after
all blanks in this study had been collected (USGS, Office
of Water Quality, written commun., 2006). Additional
contamination may have resulted from incomplete
cleaning of the sample-hose attachment, especially in
the case of carbon, which sometimes was detected in
greatest concentration in the first sample collected after
each laboratory cleaning. Therefore, this particular
constituent may have been introduced during the
cleaning process or blank sampling process and may be
routinely overestimated in the analyses.
Sample Analysis Methods
Specific conductance, pH, water temperature, and
dissolved oxygen concentration were determined by
USGS staff in the field using methods described in
Wilde and Radtke (1998). These water properties were
measured with a calibrated YSI600XL multiparameter
probe and, for measurements made at the well-head
discharge, using a flow-through cell. For depth-
dependent samples collected with the USGS well
profiler, water temperature and dissolved oxygen
were recorded but were not reported because, in
a bailed sample, these properties quickly became
unrepresentative of the water in the aquifer. Turbidity
was determined with a Hach 21 OOP turbidimeter.
Acid neutralizing capacity, bicarbonate and carbonate
concentrations were determined, usually in the lab, using
an inflection point titration method (Rounds and Wilde,
2001). For most samples, the titrations were completed
within 24 hours of sample collection. Analysis of
dissolved iron species was performed in the field using
a Hach DR/2000 field spectrophotometer. Ferrous iron
concentration was determined using Phenanthroline
reagent (Hach method 8146) and total iron concentration
was determined using Ferrover reagent (Hach method
8008). Ferric iron concentration was not reported
but can be determined by subtracting the ferrous iron
concentration from the total iron concentration. Stable
isotopic ratios 52H and 518O of water were analyzed by
the USGS Stable Isotope Laboratory in Reston, Virginia
(Coplen et al., 1991; Epstein and Mayeda, 1953; Coplen,
1994). One set of arsenic samples collected at Well 36
from 0900 to 0902 on January 18, 2006, was analyzed
-------
at the USGS National Water Quality Laboratory in
Lakewood, Colorado, using Inductively Coupled Plasma
-Mass Spectrometry (ICP-MS; Garbarino, 1999). The
remaining samples were analyzed at the EPA Robert
S. Kerr Laboratory facility in Ada, Oklahoma. Major
anions were analyzed using capillary ion electrophoresis
with indirect UV detection (Waters Quanta 4000
Capillary Ion Analyzer). Iodine was analyzed using
Lachat flow injection analysis (FIA). Nitrate, nitrite,
ammonia, and orthophosphate also were analyzed using
FIA. Trace elements and major cations were analyzed
by Inductively Coupled Plasma - Optical Emission
Spectrometry (ICP-OES) using a Perkin Elmer Optima
3300 DV system. Arsenic speciation was accomplished
using Ion Chromatography - Hydride Generation -
Atomic Fluorescence Spectrometry (IC-HG-AFS).
The method was adapted from Slejkovec et al. (1998).
Total dissolved arsenic was analyzed using ICP-OES or
ICP-MS. Samples collected prior to May 25, 2005, were
analyzed for arsenic by ICP-OES, and samples collected
on or after May 25, 2005, were analyzed for arsenic
by ICP-MS (Creed et al., 1994). For arsenic samples
collected prior to May 25, 2005, determination of arsenic
Vby IC-HG-AFS was used to represent dissolved
arsenic concentration in this report because the method
detection limit was lower. Total carbon, total organic
carbon, dissolved carbon, and dissolved organic carbon
were analyzed using methods adapted from the EPA
(Methods 415.1, 415.2 and 5310C, Standard Methods
for the Examination of Water and Wastewater [17th
Edition]).
Environmental samples were analyzed at different times,
by different methods, and by different laboratories. As
a result, the thresholds or limits used for reporting and
censoring data changed over the duration of this study.
The method detection limit (EPA, 1999) for a particular
analysis method is the "minimum concentration of
a substance that can be measured and reported with
99 percent confidence that the true value is greater than
zero." The practical quantitation limit (EPA, 1999)
is the "lowest concentration of an analyte that can be
reliably measured within specified limits of precision
and accuracy." In this report, some analysis values are
reported as less than (<) the practical quantitation limit;
these values are considered to be nondetections. Other
values are reported as estimated (E) at a value between
the practical quantitation limit and the method detection
limit. For estimated values there is confidence that the
constituent concentration is greater than zero, but there
is low confidence in the concentration value. Estimated
values are considered to be detections in this report.
Filtered (dissolved) and Unfiltered (total) Samples
Regulatory compliance samples, which comprise most
of the data presented in Figure 10, are collected and
reported as total (unfiltered) arsenic. In contrast, samples
from this study are reported as dissolved (0.45-um
filtered) arsenic. Focazio et al. (2000) have documented
large differences between filtered and unfiltered
ground-water samples. Some initial concern existed
that much of the arsenic in Norman water samples, if
sorbed onto small particulates, would be removed from
the samples during the filtering process, and filtered
and unfiltered samples could yield different arsenic
concentrations. Sample turbidity was less than one
Nephelometric Turbidity Unit (NTU) for most well-
head samples collected in this study, so differences in
arsenic concentration in filtered and unfiltered samples
were expected to be small. There also was concern that
different laboratories could yield different results from
the same sample water. To examine these possibilities,
two sets of well-head samples were collected at Norman
Well 36 on January 18, 2006. These sample sets were
sent to Shaw Environmental Laboratories in Ada,
Oklahoma, and the USGS National Water Quality
Laboratory (NWQL) in Lakewood, Colorado, for
arsenic analysis by the ICP-MS method. Each sample
set included an unfiltered sample, a 0.45-um filtered
sample, and a 0.20-um filtered sample. The arsenic
concentrations in the Shaw Environmental Laboratory
samples were 20.6 (with a laboratory duplicate of 20.3),
20.4, and 20.4, respectively. The arsenic concentrations
in the NWQL samples were 17.3, 17.7, and 17.9,
respectively. Differences in arsenic concentrations in
unfiltered, 0.45-um filtered, and 0.20-um filtered well-
head samples in this study were within the precision
of the ICP-MS technique (2-3 percent; Creed et al.,
1994; EPA, 1999). Also, based on differences in arsenic
concentrations between the two laboratories, relative
percent differences in arsenic concentrations determined
by different laboratories may be greater than 17 percent.
Though this difference is small relative to some
environmental concentrations, any difference attributable
to different analyzing laboratories is unsettling to
water-supply systems that operate wells with arsenic
concentrations near the MCL.
-------
5.0
Norman Arsenic Test Hole
Schlottmann et al. (1998) found that aqueous
concentrations of arsenic (and the geochemically related
oxyanions of chromium, selenium, and uranium) were
elevated in only one sampled sandstone zone at depth in
the Central Oklahoma aquifer near Edmond (Figure 1).
As part of the investigation of changes in water quality
with depth in the Norman area (southern Central
Oklahoma aquifer), an undeveloped site in Norman was
selected for drilling, logging, coring, and water sampling
in a test hole similar to that of Schlottman et al. (1998).
The selected test-hole site (SE1/4, Section 5, Township
09 North, Range 02 West) was in northern Norman near
the Little River (Figure 2). The USGS Central Region
Drilling Unit, using mud-rotary methods, drilled to a
total depth of 728 feet. Caliper, natural gamma-ray,
resistivity, and neutron logs (Keys, 1990) were recorded
and used to identify major water-bearing sandstones
from depths of about 300 to 728 feet (Plate 1). Seven
sandstone-dominated units or zones, ranging from 12
feet to 40 feet in thickness, were selected for coring
and water sampling (Plate 1, Figure 19). When logging
was complete, this reconnaissance hole was plugged,
and a second test hole, for collection of core and water
samples, was drilled about 20 feet to the west of the
logged hole.
Discontinuous core collection and a single-packer
sampling method were used to collect rock and water
samples from selected sandstones. First, the hole was
drilled to about 300 feet. The coring bit was inserted and
core samples were collected from 302 feet to the bottom
of the first water-quality sample zone (Zone 1, about
350 feet, Plate 1, Figure 19). The hole was then reamed
to 6 inches and air developed for several hours, until the
water reaching the surface cleared. A single inflatable
packer was then installed on 3-inch pipe at the top of the
water-quality sample zone (about 320 feet) and inflated.
A low-capacity pump was installed on 2-inch, stainless-
steel drop pipe inside the packer string at a depth of
about 310 feet. The selected sample zone was purged for
1 to 2 hours at 5 gallons per minute, until the discharge
was relatively clear (turbidity less than 500 NTU) and
field water properties stabilized. The test-hole water
sample was then bottled, preserved, and analyzed in the
same manner as samples collected from public-supply
well heads. After the sample for water-quality Zone 1
was collected, the water-quality sampling apparatus
was removed from the well and coring resumed. Rock
material was sampled by coring from 302 to 536, 568
to 598, 615 to 636, 640 to 652, and 668 to 686 feet
(Plate 1).
Norman Arsenic Test-hole Core
Core recovery in the Norman arsenic test hole was good
considering the rock properties of the Garber-Wellington
(mudrock that slacks upon wetting). Some parts of the
core were rubblized by the coring process. One example
was observed in the images of core boxes 5 and 6 at
a depth of 375 feet where rounded clasts of sandstone
set in a disrupted mudstone matrix occurred above an
underlying well-cemented conglomerate (Appendix 1).
Most of the red sandstones in the core were made up
of very-fine to fine-grained sand that was moderately
well to well sorted with respect to framework grains
(Appendix 2). The sandstones in the core were friable
and small fragments broken from the core could
be crushed with the fingers. The sandstones also
contained red mud (matrix composed of clay and silt-
sized mineral matter) between the framework grains.
The sandstones were thin to moderately bedded. The
upper and lower bounding surfaces of sandstone beds
were straight (or relatively horizontal). Some of the
lower-bounding surfaces were curved and indicative of
erosion of underlying units in the Permian. Internal to
the sandstones, some of the beds contained horizontal
laminations and ripple laminations. Irregular or curved
internal bounding surfaces are present in some beds.
Other features included planar and trough cross-bedding.
Evidence for trough cross-bedding was that the angle of
cross-bedding inclination increased upward in individual
cross-bedded units. Some of the sandstone beds
contained small spherical carbonate concretions, which
were thought to be diagenetic.
Thin to moderately bedded layers of conglomerate were
present in the core (Appendix 2). The conglomerates
tended to be massively bedded (structureless) and
contained clasts of dolomite and mudstone. The
dolomite clasts appeared to be a product of Permian
soil forming processes that were liberated from the
mudstone during Permian erosion. Most of the mud
clasts in the conglomerates were derived from the
underlying mudstones as well (mudstone rip-up clasts).
The conglomerates were well-cemented by dolomite and
could be broken only through hard impacts with a heavy
hammer.
Some of the sandstone beds in the core were above thin
conglomerate zones. Collectively, these zones fined
upward as expected for units associated with a fluvial
depositional setting (Visher, 1965, Reading, 1987).
Most of the silt- and clay-rich layers (mudrock)
in the core were red mudstone (mudrock without
-------
laminations). The mudstones were relatively massive (or
structureless). The mudstone slacked when immersed
in water. Locally, the mudstone contained features
that appeared to be paleo-root traces, rhizocretions
(carbonate accumulations associated with ancient
roots), irregular-shaped carbonate nodules, some
weak horizonation, and local chemical reduction of
the red mudstone (or locally, sandstone) to a greenish
color (redoximorphic processes). These features were
indicative of occurrence of soil forming episodes during
the Permian period (Permian paleosol formation).
Evidence for secondary iron mobilization (hematite
based on visual inspection) was present in the sandstone,
conglomerate, and mudrock preserved in the core
(Appendix 2). The iron occurred as clots and as
crenulated crusts. The clots were concretion-like and
occurred in some of the sandstone and mudrock. The
crusts appeared similar to, or were compatible with, the
movement of a local chemical oxidation front through
the Garber-Wellington sequence (similar in appearance
to liesegang banding, p. 123, Pettijohn et al., 1987).
The crusts occurred in the sandstone and mudrock.
Iron mobilization in the mudstones of the core was
dramatic. Iron would not be expected to mobilize out
of mudrock late in the burial history of the unit (that is,
iron mobilization in the mudrock that is occurring in the
present-day time frame) because the volume of water in
the mudrock today is low relative to the volume of water
moving through the aquifer sandstone on a daily basis.
Consequently, present-day iron mobilization would be
expected to occur in sandstone rather than in mudstone.
Textural evidence in core indicates that the iron in the
mudrock was probably mobilized during the early phase
of burial (water squeezed from the mud by mechanical
compaction soon after deposition and shallow burial
during the Permian period).
Norman Arsenic Test-hole Water Quality
Interpretation of the geophysical logs in Plate 1
indicates that the test hole penetrated about 50 feet
of the Hennessey Group, and nearly half of the total
thickness of the Garber Sandstone and Wellington
Formation (Figure 19). According to elevation-contour
maps of the base of the Hennessey Formation and base
of the Wellington Formation (Christenson et al., 1992),
the combined thickness of the Garber Sandstone and
Wellington Formation is about 1,500 feet at the test hole
location.
Ground-water-quality samples were analyzed from
seven predominantly sandstone zones. The zones were
labeled in order of increasing depth below land surface
as Zone 1 (320-350 feet), Zone 2 (416-456 feet), Zone 3
100 150 200 0 100
400 600 BOO 1,000
100 150 200
240 480 720
1.000 2.000 3.000 4.000
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CONSTITUENT CONCENTRATION,
IN MICROGRAMS PER LITER
Figure 19. Selected geophysical logs and water-quality samples from the deep aquifer system at the
Norman arsenic test hole, October 2004 [|J.g/L, micrograms per liter; BQL, below practical quantitation
limit; EPAMCL, Environmental Protection Agency maximum contaminant level for arsenic].
-------
(488-502 feet), Zone 4 (568-598 feet), Zone 5 (615-636
feet), Zone 6 (640-652 feet), and Zone 7 (668-686 feet)
(Figure 19, Plate 1, Appendix 3).
Sandstone Zones 2 and 3 were separated by only
32 feet but had different water types (Figure 19). In the
sampled Zones 1 and 2, the water type was calcium-
magnesium bicarbonate with a pH about 8.0 and specific
conductance less than 500 microsiemens per centimeter
(uS/cm) (Figure 19). Dissolved arsenic concentrations
were less than 10 ug/L in the two shallowest sampled
zones, Zones 1-2 (Figure 19). In sampled Zones 3
through 7, the water type was sodium bicarbonate
with a pH about 9.0 and specific conductance usually
greater than 500 uS/cm. Arsenic concentrations were
considerably greater in Zones 3 through 7 (as compared
to Zones 1 and 2), ranging from estimated 9 ug/L to
nearly 60 ug/L. Arsenic concentrations exceeded the
MCL of 10 ug/L in all zones where pH was greater
than 8.5 and specific conductance was greater than
600 uS/cm. Selenium and chromium concentrations
mostly were greater in the sampled Zones 3 through
7 than in the sampled Zones 1 and 2. Selenium
concentrations exceeded the MCL of 50 ug/L in Zones
5 and 6, and chromium concentration exceeded the
MCL of 100 ug/L in Zone 7. Also, concentrations of
carbonate, sulfate, fluoride, orthophosphate, boron, and
vanadium were greater in Zones 3 through 7 than in
Zones 1 and 2.
The contrast in water quality between Zones 2 and 3
could be an indication that the intervening mudstone is a
regional barrier to the vertical flow of ground water and,
therefore, the flow paths supplying water to Zone 2 are
much different than the flow paths supplying water to
Zone 3. Alternatively, the contrast could mean that zones
below a depth of 460 feet are richer in exchangeable
clays. The contrast in water quality between Zones 2
and 3 also could be related to the presence of a basal
carbonate-clast conglomerate (represented by a zone of
increased resistivity, Figure 19 and plate 1) in Zone 2.
Conglomerates in the Central Oklahoma aquifer contain
large concentrations of dolomite, arsenic, and iron in
the solid phase relative to the other lithofacies in the
aquifer system (S.T Paxton, Oklahoma State University,
written commun., 2005). If dolomite supply or arsenic
availability are limiting factors in the chemical evolution
of water at this depth, the presence of the conglomerate
could accelerate arsenic release.
Plate 1. Caliper, natural gamma-ray, resistivity, and
neutron logs from the Norman arsenic test
hole, SE1/4, Section 5, Township 09 North,
Range 02 West.
-------
GAMMA, IN COUNTS PER SECOND
40 100
RESISTIVITY, IN OHM-METERS
NEUTRONS, IN COUNTS PER SECOND
1,000 2,000
Hennessey Shale
Garber Sandstone
and Wellington 60
Formation
Shallow aquifer
system
Deep aquifer
system
EXPLANATION
Water-quality
sample zone
Cored
interval
Dissolved
arsenic V
(arsenate)
concentration,
in micrograms
per liter (water-
quality samples
collected
October 2004;
appendix 3;
E, estimated
below
quantitation limit;
<, less than
quantitation limit)
Lateral
Short Normal (16)
Long Normal (64)
CALIPER, 12
IN INCHES
-------
6.0
Flow Contribution and Water Quality with
Depth from an Eleven-well Investigation
Ground-water Flow and
Particle-tracking Models
The ground-water flow and particle-tracking models of
Parkhurst et al. (1996) were used to project theoretical
flow paths from perforated zones in Norman wells
back to likely recharge source areas. The theoretical
flow paths are useful to visualize the movement of
ground water and to explain general differences in water
chemistry between wells.
The ground-water flow model was designed to simulate
the flow system in the entire Central Oklahoma aquifer
as described in the late 1980s. The ground-water flow
model used to simulate the aquifer was the USGS
modular ground-water flow model (McDonald and
Harbaugh, 1988), now commonly called MODFLOW.
This model uses a block-centered, finite-difference
approach to simulate flow in three dimensions. The
Central Oklahoma aquifer simulations contained
40 columns, 60 rows, and, because vertical flow is
substantial, 12 layers. In the horizontal dimensions,
cells are 6,562 feet (2,000 meters) on a side, and cell
spacing is constant for the region of simulation. All
layers are 100 feet thick. Unlike many flow models,
the Central Oklahoma aquifer model layers do not
correspond to particular geologic units. Instead, the
layers are horizontal, and each cell is assigned properties
that represent the geohydrologic unit that is the thickest
within the cell.
Parkhurst et al. (1996) used a particle-tracking model
in conjunction with the ground-water flow model
to calibrate the flow model, assist in visualizing
flowpaths in the flow system, and integrate the results
of the flow model simulations with the analysis of the
geochemistry of the Central Oklahoma aquifer. The
particle-tracking model generates pathlines, which are
the paths of hypothetical particles of water moving
through the aquifer as simulated by the numerical flow
model. The pathlines correspond to flowpaths in the
Central Oklahoma aquifer. The particle-tracking model,
MODPATH, was developed by Pollock (1989) and
designed to be used with the MODFLOW ground-water
flow model. In general terms, MODPATH takes the
cell-by-cell flow terms (volumetric fluxes) computed by
the flow model and computes the pathlines through each
model cell. MODPATH assumes that each directional
velocity component varies linearly with each grid cell.
Particles can be placed anywhere in the model flow field
and tracked forward or backward, and traveltimes can be
computed.
The Central Oklahoma aquifer was modeled only as a
steady-state system without withdrawals because at the
time the Central Oklahoma aquifer model was developed
(in the late 1980s), MODPATH only simulated steady-
state flow. Parkhurst et al. (1996) stated that because
the 1986-87 water table they simulated did not show
substantial effects from withdrawals, simulation of
transient conditions was not necessary.
The current investigation uses the same ground-water
flow field generated by the Parkhurst et al. (1996)
MODFLOW simulation, but the current MODPATH
particle-tracking model is different. Calibrated
MODFLOW model parameters from Parkhurst et al.
(1996) were not changed for simulations done for this
report. The MODPATH particles for the current analysis
were generated at the locations of individual City of
Norman supply wells. Particles were generated along
the well bore at 5-foot intervals between the highest and
lowest known perforations. If the top of the perforations
was unknown, perforations were assumed to start 300
feet below the land surface. If the bottom of perforations
was not known, perforations were assumed to continue
to the bottom of the well. Particles were tracked
backwards to the recharge locations.
For all wells in the Norman well field, the dominant
modeled source area is south-central Oklahoma County
immediately north of Lake Stanley Draper (Figure 20).
This source area corresponds to the potentiometric high
mapped by Christenson et al. (1992), and is the part
of the aquifer that contains the thickest sequences of
sandstone (Parkhurst et al., 1996). Only flow paths for
wells 05, 07, 20, 23, 33, and 36 are shown in Figure 20
for clarity. Flow path sets for other wells are similar
to those shown and can be visually interpolated on
Figure 20. The modeled flow paths for each Norman
well mostly travel southwest from the source area into
the confined part of the aquifer, turn south within the
city, and finally arc back to the east before terminating at
the well (Figure 20).
For Well 23, which has unusually high concentrations
of arsenic in produced water, the majority of modeled
flow paths begin near the potentiometric high north
of Lake Stanley Draper (Figure 20). The flow paths
-------
EXPLANATION
I Water
Geologic Unit
I I Alluvium
CD Terrace
CD Hennessey Group
(confining unit)
I I Garber Sandstone
Norman roads
Rivers and streams
Norman boundary
'<ป. Average modeled flow path
Modeled How paths
~~] Well 20
j Well 36
i Well 33
I Well 23
Well 05
| Well 07
THA Norman arsenic test hole
20 Norman wells and number
1 8 O Sampled Norman wells and number
0 0.5 1
2 MILES
0 0.5 1 2 KILOMETERS
Albert EquaMraa Conta function
Road* from Norman GIS Department
Geologic data from Oklahoma Geokjglcal Survey
Figure 20. Modeled flow paths for selected wells in the Norman well field. Dashed blue lines represent a typical or
average modeled flow path to each selected well.
trend southwest, descending under the confining unit
and progressing into Cleveland County, where the
flow paths turn to the south near U.S. Highway 77
and then to the east near Robinson Street (Figure 20).
If a typical flow path is selected to represent flow to
Well 23, this path passes within one mile of several
wells in the Norman well field before reaching Well 23
(Figure 20). When plotted in order from most proximal
to most distal (from the recharge area), the historical
arsenic data for these wells express mostly upward
trends in minimum, median, and maximum detected
arsenic concentrations with distance along the flow path
(Figure 21), validating the aquifer conceptual model.
Median arsenic concentration ranges from 3.9 ug/L in
Well 20 to 231 ug/L in abandoned Well 24 (Figure 21).
In the four wells east of Well 24 (23, 25, 06, and 05), this
trend is reversed, probably because the aquifer materials
quickly become coarser-grained, more conductive, and
better flushed to the east (Figure 21).
The MODFLOW simulation of Parkhurst et al. (1996)
was designed to simulate the ground-water flow at an
aquifer scale. The model grid was relatively coarse
(2,000 meters by 2,000 meters) because of limitations
of computer memory at the time the simulation was
performed, and the model simulates an assumed steady-
state condition not reflective of changes due to ground-
water withdrawals. Thus, the pathlines generated by the
MODFLOW simulation are indicative of the general
direction of ground-water flow but should not be
considered to exactly represent the path of ground-water
movement.
Traditional Methods of Hydraulic
Testing - Well 23
In preparation for hydraulic testing in Well 23, a video
log was run to inspect the integrity of the casing,
examine the degree of scale buildup, and verify the
perforated depths listed on the original perforation
record. Perforated depths on the perforation log were
about 1 to 2 percent less than the depths noted on the
video log (Figure 22). Differences in the recorded depths
are most likely caused by differences in line-counter
calibration. Errors of this type can result in the accidental
perforation of low-permeability zones at greater depths.
Consequently, some zones identified as perforated
may not produce substantial quantities of water. Also,
the video log showed several sets of perforations that
were completely plugged by scale buildup. This is
another scenario in which a zone could be perforated
but nonproducing. Water was observed flowing into the
well casing at several depths, including cascading water
at 296 and 343 feet and jetting water at several depths.
At three depths (479, 506, and 569 feet), water was
observed flowing from the well into the aquifer rock.
-------
0 0.5 1 2 KILOMETERS
Rivers and streams
Norman boundary
* * A*. Typical modeled flow path for well 23
'[HI A Norman arsenic test hole
I I Garter Sandstone 1ฉ O Norman wells and number
Norman roads H ii O Sampled Norman wells and number
Geologic Unit
I I Alluvium
I I Terrace
I I Hennessey Group
(confining unit)
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CITY OF NORMAN WELLS
EXPLANATION
Arsenic sample Median concentration
3 Number of historic ... EPA (1986) MCL for
BJ*"' arsenic in drinking water
(1) Number of historic EPA(2001)MCLfor
samples with arsenic in drinking water
Figure 21. Typical modeled flow path for Norman Well 23 and trend in well-head arsenic concentrations [MCL,
Maximum Contaminant Level].
EXPLANATION
Packer-tested Interval r-^ Perforated Inter/a] from
*i"^ with concentration of video log showina
arierfcViivSer percentflow contnbunon SPECIFIC SODIUM BICARBONATE VANADIUM BORON
V Pumping CONDUCTANCE. IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION
I Perforated interval - water level MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN
from perforation record o Pump rrtake PER CENTIMETER PER LITER PER LITER
WELL CONSTRUCTION 0 20 40
300
350
LJ 400
|
to
Q
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vllCROGRAMS IN MICROGRAMS
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0 15 30 45 60 Q 20406080100 7.0 8.0 9.0 10.0 0.00 1.25 2.50 0 20 40 60 80 0 150 300 0 100 200 30
^VADMNJJITQ^' PERCENTAGE OF pH, IN CONSTITUENT CONSTITUENT CONSTITUENT CONSTITUENT
IN AM urn i o TOTAL FLOW STANDARD UNITS CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION
IN MILLIGRAMS IN MILLIGRAMS IN
PER LITER PER LITER
VllCROGRAMS IN MICROGRAMS
PER LITER PER LITER
Figure 22. Results of wireline logging, impeller-flowmeter, and packer tests in Norman Well 23, September 2004.
[Lig/L, micrograms per liter; API, American Petroleum Institute; NQ, not quantifiable; %, percent].
-------
An impeller-flowmeter log was ran in Well 23 to
determine zonal flow contributions during production.
A temporary pump was installed at 446 feet below land
surface, about 50 feet below the pumping water level
and about 140 feet above the depth of the pump during
normal production. Throughout flowmeter logging,
the production rate was maintained at 200 gallons per
minute. The impeller-flowmeter log identified a 30-foot
perforated interval near the temporary pump intake as
the greatest contributor of water to the well. This interval
(458-488 feet below land surface) supplied nearly two
thirds (64 percent) of the well discharge (Figure 22).
The next two deepest zones, with perforated intervals of
495 to 508 and 516 to 523, produced 19 and 16 percent
of the well discharge, respectively (Figure 22). The
zones below 525 feet contributed only 1 percent of the
well discharge according to the impeller-flowmeter log
(Figure 22). The quantity of water being contributed
from zones above the temporary pump intake could not
be determined because of limitations of the impeller-
flowmeter tool.
Seven perforated zones or groups of zones identified
in the video log were selected for packer testing. Five
zones were sampled using a packer spacing of 10 feet
and two zones were sampled using a packer spacing
of 30 feet. Each zone was tested at a production rate
of about 5 gallons per minute for 1 to 2 hours using a
submersible pump. No water-level measurements were
made outside the packer string to verify that the packers
were sealed against the casing. One targeted zone failed
to produce water, however, because the packers were
placed at the wrong depth. When the problem was
corrected, the targeted zone produced water. Because the
wrong placement resulted in no production, the packers
are believed to have sealed properly against the casing
wall.
Samples were collected in the same manner as test-hole
and well-head samples, and a sealed flow-through cell
was used for measurement of field water properties.
Samples were acidified, if necessary, and placed on ice
immediately after collection. Alkalinity titrations were
completed on site after all other samples were collected
and preserved.
With the exception of data from the shallowest zone
(403-412 feet below land surface), the data indicated
relatively little variation in water quality between
sampled zones in Well 23 (Figure 22, Table 4).
Dissolved arsenic concentrations (as arsenic V) exceeded
10 ug/L in all zonal samples from Well 23 (Figure 22).
At 140 ug/L, arsenic concentration was greatest in the
water produced from 458 to 488 feet below land surface
(Figure 22). The arsenic concentration mostly decreased
with distance from this interval, measuring 69 ug/L
in the shallowest tested interval (404-413 feet) and
107 ug/L in the deepest tested interval (568-577 feet;
Figure 22). Selenium concentrations greater than
50 ug/L also were measured in all zonal samples from
Well 23 (Figure 22).
USGS Well Profiler
The results of water-quality sampling and velocity
profiling in 11 selected Norman wells are presented in
Appendix 4 and 5. Each figure in Appendix 5 (5A-5K)
includes a natural gamma-ray or spontaneous-potential
log for general lithologic determination. To the right
of each log is a well construction record showing open
(perforated or screened) intervals, where known, the
estimated depth of the pump intake, and the pumping
water level at the time of testing. To the right of the
well construction information are estimates of flow
contribution percentages from open intervals. This graph
also includes an estimate of percentages of flow coming
from above and below the pump, where applicable.
Estimates of flow contribution from intervals above
the pumping water level are marked "cascading." The
estimate of well yield (Q) appears at the top of the flow
contribution graph.
The remaining graphs show water-quality samples from
various sample depths in the well. The samples collected
at each well include about six depth-dependent samples
and one well-head sample. Some wells (02, 05, and 36)
were sampled twice. These wells were resampled to
conduct more precise analysis of dissolved arsenic by
the ICP-MS method; results of the second sampling are
presented. From left to right the water-quality graphs on
each figure show selected field water properties, major
cations, major anions, and trace elements (including
arsenic) that were routinely detected. For some
constituents, an additional scale was placed at the top
of the graph so related constituents could be displayed
together. Depth-dependent samples are represented
by filled markers at the appropriate sample depth, and
well-head samples are represented by hollow markers
at the approximate depth of the pump. Constituents
that were not detected in depth-dependent samples
were graphed as having a zero concentration. Also, two
vertical reference lines appear on each figure to indicate
where pH exceeds 8.5 standard units and arsenic exceeds
10 ug/L.
Tracer-pulse Velocity Profiles
Because disposal of large volumes of well discharge
was problematic, the tracer-pulse velocity profiles in this
study were conducted after less than 8 hours pumping
duration. Flow contribution percentages varied widely
between wells. In many wells, greater than 50 percent of
the well yield originated from one or two contributing
zones near the pump intake. Whether this phenomenon is
real or simply an artifact of the zonal flow computation
-------
Table 4. Well-head values and maximum and minimum values of constituents measured in depth-dependent samples from 11 selected wells, Norman, Oklahoma,
2003-2006.
1
02
05
06
07
13
15
18
23p
23
31
33
36
-
A
=
a
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351426097232201
351409097231801
351357097242001
351414097293901
351550097283801
351648097285101
351726097290901
351401097252301
351401097252301
351542097262801
351541097245301
351633097241901
0)
1 y
ซ 0
y
-------
method is unknown. That the majority of well discharge
can originate from one zone is surprising, but is
consistent with an impeller-flowmeter log from Gossell
et al. (1999) who found that 48 percent of the discharge
from a high capacity well was produced by only
6 percent of the total screened interval. Computations of
percentages originating from above and below the pump
intake do not routinely show greater production from
either side of the pump intake. Production is often evenly
(about 50 percent and 50 percent) or nearly evenly split
(about 40 percent and 60 percent) between either side of
the pump intake in Norman wells. Lithology and zone
thickness, as determined from the natural gamma-ray or
spontaneous-potential log, do not appear to be reliable
indicators of the quantity of flow contribution. In some
wells, though, thicker and cleaner sandstones do appear
to contribute more flow than thinner and finer-grained
sandstones.
In terms of repeatability, tracer-pulse velocity profiling
is sensitive to the water-level and pumping duration
prior to testing. A replicate tracer-pulse velocity profile
was completed in Well 23, about 1 month after the
completion of the initial profile. Well 23 was unused
at the time of testing, and the water level and pumping
duration were nearly identical between tests. Except
for the uppermost zone, which is influenced greatly by
cascading water, well velocities and zonal contribution
percentages were nearly identical. The tracer-pulse
traveltimes were repeatable to within 2 seconds at most
depths and to within 5 seconds at depths farthest from
the pump (Figure 16). These results translate to about
a 2 percent difference in traveltimes for all depths in
the well. Repeated graphical analysis of the tracer-
pulse traveltime data showed that velocities and zonal
contribution percentages are mostly repeatable to within
5 percent. No repeat measurements were completed
to determine the effect of the PVC access tube on
repeatability of down-hole tests used in this study.
The changes in well-bore velocity caused by zonal flow
contribution tend to occur as slope breaks, not as gradual
changes in slope (curves). Changes in velocity across
thick contributing intervals (30-40 feet) sometimes
occur as multiple distinct slope breaks, not curves. This
phenomenon indicates that contributed water may be
entering the access tube only at discrete depths, and that
the water inside the access tube may not be identical
to water outside the access tube at a given depth. If
contributed water is entering the access tube at discrete
depths and not continuously, this could be caused by
constrictions (such as pump-column pipe connections)
that may force locally contributed water into the access
tube. However, abrupt changes in slope of tracer-pulse
traveltimes also were observed in Wells 23 and 33,
which were not equipped with access tubes at the time of
the tracer-pulse velocity profile.
Estimates of Well Yield
The tracer-pulse log data and available well-construction
details for each selected well were used to estimate
well yield. Estimated well yields (Table 5) were mostly
within 20 percent of those in City of Norman records
(Table 1). The tracer-pulse estimates tended to be greater
than the reported well yields. The estimates are probably
slightly overestimated because first arrivals of dye were
used to compute traveltimes. The time of first arrival
corresponds to the maximum velocity of water flowing
through the center of the column pipe. Small, positive
differences in well yield estimates also could be caused
by the difference in backpressure between pumping
to the distribution pipe and pumping to waste or by
differences in pumping duration between tracer-pulse
profiling and actual production. The estimates of yield
for Wells 15 and 31 were more than 20 percent different
from values reported in City of Norman records. The
reason for the abnormally large disagreement in tracer-
pulse-determined estimates and reported yield values in
these two wells is unknown. Larger differences could
result from underestimating scale thickness inside the
column pipe or from seasonal changes in aquifer water
levels and well output since the Norman records were
created.
Depth-specific Water Quality
Well-head arsenic concentrations measured in this study
compare favorably with historical well-head samples
at each well (Figure 23). All well-head arsenic samples
collected in this study were within the range of historical
well-head concentrations (Figure 23). Most depth-
dependent arsenic samples also were within the range
of historical well-head concentrations. Only Wells 02
and 36 had depth-dependent arsenic samples that were
outside the range of historical well-head concentrations
(Figure 23).
Most of the selected wells (06, 07, 13, 15, 18, 23,
and 31) showed elevated or near-elevated arsenic
concentrations at all depths in the well (Appendix 4,
Figure 23). For these wells, well-modification techniques
would be ineffective in lowering well-head arsenic
concentrations to less than 10 micrograms per liter. Wells
02, 05, 33, and 36, however, showed some potential for
successful application of well modification techniques
for arsenic remediation. All these wells lie near the
Hennessey-Garber contact (Figure 2). Wells 02 and 05
are on the eastern margin of the well field; Wells 33 and
36 are on the northern margin of the well field (Figure 2).
Elevated arsenic concentrations in Wells 02, 05, and 36
only were detected in depth-dependent samples from
the bottom of the well. In Well 33, elevated arsenic
concentrations were not detected at any depth. In fact, no
arsenic concentrations greater than 1 ug/L were detected
in the depth-dependent samples or the well-head samples
-------
Table 5. Estimated well yields determined from tracer-pulse velocity profiling for 11 selected wells in Norman,
Oklahoma, 2003-2006
Well
02
05
06
07
13
15
18
23
31
33
36
USGS station
number
351426097232201
351409097231801
351357097242001
351414097293901
351550097283801
351648097285101
351726097290901
351401097252301
351542097262801
351541097245301
351633097241901
depth
ฐfU
560
640
610
660
630
615
600
585
550
610
670
mm
55
95
87
154
125
140
139
89
84
108
103
Vco,
10.2
6.7
7.0
4.3
5.0
4.4
4.3
6.6
6.5
5.6
6.5
rco,
2.0
2.0
2.0
2.0
2.0
2.5
2.0
2.0
2.0
2.0
2.0
A01
max
0.0873
0.0873
0.0873
0.0873
0.0873
0.1364
0.0873
0.0873
0.0873
0.0873
0.0873
min
0.0767
0.0767
0.0767
0.0767
0.0767
0.1231
0.0767
0.0767
0.0767
0.0767
0.0767
Estimated well yield, in
gallons per minute
max
400
265
275
168
198
270
170
258
257
222
255
min
351
233
242
148
174
243
149
227
226
195
225
mean
376 ฑ24
249 ฑ 16
259 ฑ 17
158 ฑ 10
186 ฑ 12
256 ฑ 13
159 ฑ 10
242 ฑ 16
242 ฑ 16
208 ฑ 13
240 ฑ 15
Well yield
from
Norman
records,
in gallons
per minute
335
212
218
182
190
164
147
250
172
219
260
Relative
percent
difference
11.4
15.9
17.1
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EXPLANATION
ป Historic well-head
arsenic sample,
1984-2001
Median concentration
of historic well-head
arsenic detections
3 Number of historic
samples
(1) Number of historic
samples with
nondetections
05 Sampled wells, this study
o Well-head arsenic
sample, this study
Depth-dependent arsenic
sample, this study
--- EPA(1986)MCLfor
arsenic in drinking water
--- EPA(2001) MCLfor
arsenic in drinking water
^ Well yield, in gallons
per minute, from Norman
flies (see table 1)
01 02 03 04 05 06 07 08 10 11 12 13 14 15 16 18 19 20 21 23 24 25 31 32 33 34 35 36 37 38 39 40
CITY OF NORMAN WELLS
Figure 23. Well-head arsenic concentrations (1984-2001), median values, and maximum contaminant levels (MCL)
for arsenic in the Norman well field, 2003, with depth-dependent and well-head arsenic concentrations
from 11 selected wells, 2003-2006.
-------
at Well 33 (Table 4, Appendix 4). The sampler, however,
could not access the bottom of Well 33 because of the
presence of a pump shroud. In 2005, Well 33 produced
one well-head water sample (not included in Table 1 or
Figure 11) which exceeded the arsenic MCL. The water
responsible for elevated well-head arsenic concentrations
is believed to be originating from the perforated zones
below the pump intake (606-622 feet). Also, because the
well-head sample from this investigation had an arsenic
concentration less than 1 ug/L (Table 4), these deep
perforated zones are likely to cause deterioration of well-
head water quality only after the well has been pumped
for periods longer than 8 hours.
Isotopic Composition of Waterfront Wells
Stable isotopes of water can serve as approximate
surrogates for water age or time since recharge in some
aquifer systems. To investigate the utility of this relation,
as defined by Parkhurst et al. (1996), samples from the
selected Norman wells (except Well 33) and the arsenic
test hole were analyzed for the stable isotopes of water
(Figure 24). Oxygen-18 (518O) and deuterium (52H)
abundances in water are expressed as ratios as a per mil
(parts per thousand) difference relative to the Vienna
Standard Mean Ocean Water (VSMOW) (Gonfiantini,
1978). Usually, the top and bottom depth-dependent
samples from each well were submitted for isotopic
analysis because these samples are representative of a
single zone (not mixtures). A well-head sample also was
submitted for isotopic analysis.
Water sampled from 10 selected Norman wells had 518O
values that ranged from -5.98 to -6.82 per mil, with
a median value of -6.39 per mil (Figure 24); the 52H
values ranged from -34.8 to -42.4 per mil with median
value of -38.4 per mil (Figure 24). Water sampled from
the Norman arsenic test hole had 518O values that ranged
from -5.70 to -6.79 per mil, with a median value of
-6.68 per mil (Figure 24); the 52H values ranged from
-34.0 to -42.8 per mil with median value of-41.6 per mil
(Figure 24). These ranges are consistent with published
values of isotopic ratios in continental precipitation at
mid-latitudes (Kendall and Coplen, 2001) as well as
previously measured isotopic ratios in ground water of
the Central Oklahoma aquifer (Parkhurst et al., 1996).
The ground-water samples mostly plot along a line that
is parallel to and about 2.1 per mil (52H) greater than the
global meteoric water line (Craig, 1961; Figure 24). This
deuterium excess value of 2.1 per mil is consistent with
the value reported by Parkhurst et al. (1996) for ground
water in the Central Oklahoma aquifer (Figure 24).
Parkhurst et al. (1996) found a relation between 52H
and water age determined from tritium and radiocarbon
dating in the Central Oklahoma aquifer. Though not a
perfect relation, water age increases with decreasing
52H. According to this relation, the youngest water
was found in Wells 18, 02, and the shallowest sampled
zones of the arsenic test hole (320-350 feet below land
surface) (Figure 24). The oldest water sampled was
found in Well 07 and intermediate sandstone zones of
m
Q.
HI
HI
Q
-7.0 -6.9 -6.8 -6.7 -6.6 -6.5 -6.4 -6.3 -6.2 -6.1 -6.0 -5.9 -5.8 -5.7 -5.6 -5.5
8"OXYGEN, IN PER MIL
Figure 24. Plot of 818Oxygen and 8Deuterium for selected wells in the Norman well field. W indicates samples from
public-supply wells and TH indicates samples from the Norman arsenic test hole.
-------
the arsenic test hole (568-598 feet below land surface).
Well 07, which is farthest west in the confined part of the
aquifer, draws some of the oldest water in the well field
according to the NAWQA conceptual model and the 52H
- age relation.
According to the age relation (Parkhurst et al., 1996),
the ages of water in the test hole could range from
only a few hundred years before present to more than
30,000 years before present. This wide range in age,
as compared to well samples, is contradictory to ages
expected from the modeled flow paths in Figure 20
and could be characteristic of the natural, undeveloped
flow system. Completed wells, after years of seasonal
pumping stresses, could develop a narrower age
signature due to mixing by intra-borehole flow between
zones when the well is not being used (Zinn and
Konikow, 2007). The range in estimated ages of test-
hole water also could be a result of the imperfect relation
between age and 52H, or the interception of units in the
test hole that are hydrologically isolated from regional
flowpaths.
The 52H of samples from the test hole indicates a
substantial change in estimated water age from the two
shallowest sampled zones (320-350 and 416-456 feet
below land surface) to the next lowest sampled zone
(488-502 feet below land surface, Figure 24). This
gap between younger and older water (Figure 24)
corresponds to the gap between detected and non-
detected arsenic in zonal water samples (Figure 19).
Coincidently, the test-hole sample with the greatest
apparent age (Zone 4, Figure 24) appears, at least
qualitatively, to be one of the least permeable (shaliest)
sandstone units in the test-hole gamma-ray log
(Figure 19).
Major-ion Water-quality Trends with Depth
Piper (1944) diagrams were used in this report to
illustrate water-type in selected wells and characterize
common trends in water quality with depth. In Piper
diagrams, anion and cation compositions are plotted
in milliequivalents on separate ternary diagrams and
are projected into another, diamond-shaped diagram.
The location of the data point in the diamond reveals
the general composition of water and may indicate a
water source. If several analyses trend in a line or curve,
the position and direction of the trend are indicative
of active chemical processes or mixing of water from
different sources. If all depth and well-head samples
from the 11 Norman wells are plotted on the diagram,
three major processes are evident - cation exchange,
influence of sulfate-rich rocks (Hennessey Group), and
the influence of brine (Figure 25). The pattern of data
points in this study is consistent with the pattern for
all wells in the Central Oklahoma aquifer (Figure 25)
and the pattern for high-arsenic wells in the Central
Oklahoma aquifer (Schlottmann et al., 1998).
All analyses in the ternary diagram for cations plotted
along a line representing a magnesium to calcium ratio
of about 1.4. The sodium plus potassium proportion
ranged from about 20 percent to about 100 percent,
usually increasing with depth in individual wells
(Figure 25). This trend represents the process of cation
exchange and shows a continuous transition from a
calcium-magnesium dominated water type to a sodium
dominated water type. This transition can occur rapidly
with depth as in Well 36 and the Norman arsenic test
hole (Figure 25). In the test hole, the process was most
pronounced. The increase in sodium plus potassium
proportion was nearly 65 percent from the sandstone
Zone 2 (ending at 456 feet below land surface) to the
sandstone Zone 3 (beginning at 488 feet below land
surface).
The proportions of sulfate and chloride in the ternary
diagram for anions tended to increase with depth in
individual wells (Appendix 4). This trend indicates the
influence of brine on wells that are drilled too deep or
wells that are in the confined aquifer system. Wells in
the confined aquifer system, such as Well 07 and Well 23
(Figure 25), showed the possible influence of dissolution
of sulfate-rich rocks (Parkhurst et al., 1994). The data
from these wells showed the beginnings of a transition
from a sodium-bicarbonate water type to a sodium-
chloride-sulfate water type. An increase in the sulfate or
chloride proportion also could indicate connate water
that has not been sufficiently flushed from the aquifer by
recharge.
In the composite diamond-shaped part of the Piper
diagram, the general evolution of water with depth is
from a calcium-magnesium-bicarbonate water type, to
a sodium-bicarbonate water type, to a sodium-chloride-
sulfate water type (Figure 25). This is the same trend
seen in regional maps of well-head analyses in the
Norman area (Figure 9; Parkhurst et al., 1994). Wells
that plot further along this trend are more likely to
produce water with arsenic concentrations exceeding
the MCL. Analyses from different depths in some
wells, such as Well 36 and Well 05, are spread along
the cation-exchange trend (Figure 25). These wells
are the most likely to benefit from the remediation
techniques examined in this report because these wells
will have greater contrast in water quality between
individual zones. From the results of this study, wells
producing water with sodium plus potassium greater
than 90 percent of milliequivalent cations tend to be poor
candidates for remediation by well modification because
the cation-exchange process (and release of arsenic) is
too far advanced.
The transition from calcium-magnesium-bicarbonate
water to sodium bicarbonate water occurred abruptly
in Wells 02, 05, and 36, as did the transition from
low-arsenic water to high-arsenic water (Appendix 5).
-------
EXPLANATION
Arsenic Test Hole
Well 33
Well 36
Well 02
Well 05
Well 06
O Wells 13,15, and 18
Well 31
Well 23 and well 23 packer tests
Well 07
Other wells in the Central Oklahoma aquifer
from Schlottmann et al. (1998)
Composition of brine from Schlottmann
etal. (1998)
CALCIUM
CHLORIDE
PERCENT
Figure 25. Piper diagram showing water types in the arsenic test hole and selected wells (colored circles) in the
Norman well field, with data from Schlottmann et al. (1998) (empty faded circles). The data from this
study (Norman well field) show trends very similar to the Schlottmann data (wells from the Central
Oklahoma aquifer).
Abrupt changes in water quality with depth may be good
indicators that intervening low-permeability units may
be laterally pervasive.
Iron Species
Because dissolved iron species and arsenic
concentrations are related in some aquifer systems, water
samples were analyzed for ferrous and total dissolved
iron using field methods. The maximum ferrous iron
(Fe II) concentration detected in Norman wells was
0.82 milligrams per liter. Ferrous iron concentrations, as
a percentage of total iron concentrations, ranged from
0 to 100 percent, with a median of 43 percent. Ferrous
iron accounted for about 30 to 60 percent of total iron
in most samples. About 14 percent of samples had no
detection of ferrous iron and about 6 percent of samples
had ferrous iron concentrations that equaled total iron
concentrations (Appendix 4).
Other Characteristics Related to Arsenic Release in the
Central Oklahoma Aquifer
Because the cation-exchange process (by increasing pH)
indirectly causes desorption of arsenate in the Central
Oklahoma aquifer, indexes such as the sodium/calcium
milliequivalent ratio (Figure 26, Table 4) or sodium
adsorption ratio (Appendix 4) are related with dissolved
arsenic concentrations. Also, vanadium concentrations
are related with arsenic concentrations as the mechanism
for vanadate release is similar to that of arsenate
(Figure 26). ApH greater than 8.5 and conductance
greater than 500 uS/cm are indicators of elevated arsenic
concentrations in water from Norman wells (Figure 26).
Fortunately, measurement of these properties is easy,
fast, and inexpensive. Relations between these properties
and dissolved arsenic are not perfect, though, and could
not be used to accurately predict arsenic concentrations
in the Norman well field.
Orthophosphate andSulfate
Arsenic concentration is related with Orthophosphate
concentration, but Orthophosphate concentrations
measured in Norman wells were relatively small
(Figure 26). In Well 23, which had the greatest dissolved
arsenic concentrations, Orthophosphate was measured
from 0.049 to 0.064 milligrams per liter (Figure 26).
Arsenic concentration also is related with sulfate
-------
a
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60
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BDL
* Arsenic analyzed by ICP-MS
,....,....
ฐ Arsenic V analyzed by IC-HG-AFS . :
" Well 07 sample
Well 23 well profiler sample
Well 23 packer test sample
;
Drinking-water standard for arsenic
-
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7.0 7.5 8.0 8.5 9.0 9.5 400 600 800 1,000 1,200 1,400
pH, IN STANDARD UNITS SPECIFIC CONDUCTANCE, IN MICROSIEMENS PER CENTIMETER
150
120
90
60
30
BDL
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SULFATE, IN MILLIGRAMS PER LITER ORTHOPHOSPHATE PHOSPHOROUS, IN MILLIGRAMS PER LITER
150
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VANADIUM, IN MILLIGRAMS PER LITER
SODIUM/CALCIUM MILLIEQUIVALENT RATIO
Figure 26. Graphs of selected constituent concentrations that are related with arsenic concentrations in Norman
wells. Samples from Well 07, which is in western Norman, had much greater specific conductance and
sulfate concentration than samples from other selected wells [ICP-MS, inductively-coupled plasma-mass
spectrometry; IC-HG-AFS, ion chromatography-hydride generation-atomic fluorescence spectrometry;
BDL, below practical quantitation limit].
-------
concentration, another ion known to compete with
arsenic for sorption sites (Figure 26) (Stollenwerk,
2003). However, Well 07, which had the greatest sulfate
concentrations (three times greater than any other well),
had dissolved arsenic concentrations around 20 ug/L
(Figure 26). Arsenic competition with orthophosphate
and sulfate for sorption sites may be an active process
in the Central Oklahoma aquifer, but it is probably not
the dominant process causing arsenic desorption in the
Norman area.
Barium and Strontium
A few constituents, especially barium and strontium,
are inversely related with arsenic (Appendix 4 and 5).
Barium and strontium concentrations are usually greatest
in the shallower depth-dependent samples from Norman
wells and often tend to decrease with depth (Appendix 4
and 5).
Boron
Though boron concentrations are not regulated in
drinking water, boron is problematic in irrigation water
because elevated concentrations can be harmful to
vegetation. According to Hem (1989), concentrations
as low as 1 mg/L can be toxic to some plants. Boron
concentrations exceeded 1 mg/L in every sampled well
except Well 33 (Table 4). Boron concentrations greater
than 2 mg/L were measured in Wells 02, 05, 06, 07, and
23 (Table 4). The concentrations measured in Well 07
(4.5 to 5.1 mg/L) are comparable to those measured in
ocean water (Hem, 1989). For the data collected in this
investigation, boron concentration is strongly related to
sodium concentration (Appendix 4 and 5).
Chromium, Selenium, and Uranium
Arsenic is not the only contaminant of concern for
drinking-water use in the Norman well field. In some
of the wells sampled in this study, dissolved chromium
concentrations are near the MCL of 100 ug/L (Table 4).
Chromium concentrations greater than 70 ug/L were
found in depth-dependent samples from Wells 02, 05,
and 36 (Table 4). One depth-dependent sample from the
bottom of Well 05 contained a chromium concentration
of 114 ug/L and was the only sample that exceeded the
MCL (Table 4). The wells that appeared to be the best
candidates for arsenic remediation also were those with
the greatest chromium concentrations.
Chromium concentration decreased sharply with
increasing sodium concentration in most wells
(Appendix 5). This relationship contradicts findings of
Schlottmann et al. (1998), who found a weak increase
in chromium concentrations with increasing sodium in
wells from the entire Central Oklahoma aquifer.
The MCL for selenium is 50 ug/L, but the practical
quantitation limit for some analyses in this report is
100 ug/L. Therefore, some wells with no detection of
selenium could exceed the MCL. Though selenium
was detected in water from most sampled wells,
concentrations exceeding the MCL were detected only in
Well 23 (Table 4).
The MCL for uranium is 30 ug/L. Uranium was detected
in water from Wells 07 and 23, which had well-head
concentrations of 16 ug/L and 85 ug/L, respectively
(Table 4). Concentrations exceeded the MCL in the two
deepest samples from Well 07 and in all depth-dependent
samples from Well 23 (Appendix 4, Table 4).
-------
7.0
Comparison of Traditional Methods and
USGS Well-profiler Methods
Norman Well 23 (Table 1) was selected for a comparison
of depth-dependent water-quality data collected using
traditional methods (packer tests and impeller-flowmeter
logs) and the USGS well profiler (depth-dependent
sampling and tracer-pulse logs). This well produced
water with relatively high dissolved constituent
concentrations and was believed to have good contrast
in arsenic concentrations between zones (Figures 11
and 22). The purpose of the comparison was to evaluate
whether the traditional methods and USGS well profiler
methods yielded comparable data and to determine if
one of the methods yielded more useful results than the
other. The comparison showed that the two methods of
velocity logging are different, and neither is perfectly
suited to the problem addressed in this study. Impeller-
flowmeter velocity data are collected at conditions
that may differ greatly from production conditions,
especially when the pump intake is located near the
bottom of the well during normal production. Many
impeller-flowmeters, like the one used in this study,
cannot quantify contribution from open intervals above
the pump intake because of a lack of space for the tool to
fully deploy. Likewise, tracer-pulse velocity logs cannot
quantify contribution from open intervals within a few
feet of the pump intake. Tracer-pulse velocity logs are
capable of estimating flow contribution from cascading
water, though. The tracer-pulse velocity profile also
requires many assumptions and simplifications about
cross-sectional areas and velocities in the well.
With inflatable straddle packers, a water sample
originates from only one zone (if the packers seal against
the casing), but the sample is not collected under normal
pumping conditions. A sampled zone, in reality, may
produce water during packer tests but be nonproducing
during normal pumping conditions. The USGS well
profiler, in comparison, collects a sample during normal
pumping conditions, but the sample represents a
mixture of water from multiple producing zones. Also,
the sample is collected at a single point in the well; if
the sampling device is located next to a perforation at
the time of sampling, the sample water retrieved may
not be truly representative of the mixture of water in
the well bore at a given sample depth. The USGS well
profiler may not be well suited for determining arsenic
concentrations in individual zones, but the well profiler
is useful as a qualitative tool for assessing remediation
possibility. The depth-dependent sampling method
can identify the depth in the well bore at which water
becomes unsuitable for public supply (exceeds the
MCL), even without any data on flow contribution. The
USGS well profiler does offer considerable savings in
terms of cost and well down-time.
Differences in Flow Data
The flow-contribution data generated by the impeller-
flowmeter method (Figure 22) and the tracer-pulse
method (Appendix 5H) compare poorly. The poor
relation is probably a result of the difference in pump
placement during the two tests. Ideally, the intake would
be in the same location for both tests, but the impeller-
flowmeter tool used in this study could only log below
the pump. To maximize the amount of data collected
with the impeller-flowmeter, the pump was raised to a
location just below the pumping water level. The tracer-
pulse log was completed with the pump intake at the
bottom of the well because this is the configuration used
during production. Both flow-logging methods identified
the zone nearest the pump intake as the greatest producer
of water to the well. However, the greatest producing
zone identified by the tracer-pulse method was shown
to produce almost no water in the impeller-flowmeter
test. This result indicates that pump placement can have
profound influence over zonal contribution percentages.
If correct, this finding indicates that in some cases water-
quality problems could be solved simply by moving the
pump intake farther away from contaminated zones in
the well.
Differences in Water-quality Data
Because packer testing samples produce zonal water-
quality data and USGS well-profiler samples collect
depth-dependent water-quality data, comparisons of
water quality using the two methods are problematic.
Changes in depth-dependent water quality will be more
subtle because of mixing and will spatially lag changes
in zonal water quality determined from packer tests.
Also, the magnitude of influence of zonal water quality
on depth-dependent samples is related to the proportion
of flow coming from the zone as a percentage of total
flow at that sample depth.
Unfortunately, not much contrast in zonal water quality
existed in Well 23. The pH of samples in both tests was
relatively comparable, remaining around 9.0 for all
depths and zones (Figure 22, Appendix 4 and 5). Specific
-------
conductance, however, was different for many depths.
Most major ions were similar between the packer testing
and depth-dependent samples (Figure 22, Appendix 4).
The major-ion data generated by the two methods plot
in the same position on a Piper diagram (Figure 25).
Results of trace-element analysis were less consistent,
but were still similar (Appendix 4).
Using the USGS well profiler, mass-balance calculations
of zonal water quality are possible, but in practice do
not always yield meaningful results in Norman wells.
Mass-balance calculations of zonal concentrations
of low-level constituents such as arsenic are not
meaningful, especially when constituent concentrations
approach the method detection limit (or the limit of
analytical precision). Therefore, the USGS well profiler
is not a good choice for collection of data to be used
in applications such as geochemical modeling. The
depth-dependent water-quality data collected by the well
profiler are useful, however, as a qualitative tool for
identification of zones that may degrade water quality in
the Norman wells. The depth-dependent water-quality
data, even without flow contribution data, show the
depth at which the water mixture in the well becomes
unsuitable for public supply.
-------
8.0
Implications for Arsenic Remediation:
Well Modification and Well Response
Wells 06, 07, 13, 15, 18, 23, and 31 were determined
to be poor candidates for remediation by well
modification, either because all zones produced water
with elevated arsenic concentrations or because one
or two high-arsenic zones supplied most of the water
to the well (Table 4, Appendix 5). Wells 02, 05, 33
and 36 were better suited for remediation by well
modification. Elevated arsenic concentrations were
identified at depth in each of these four wells except
Well 33 (Table 4). All depth-dependent samples from
Well 33, as well as the well-head sample, had arsenic
concentrations less than 1 ug/L (Appendix 4). A pump
shroud, however, prevented collection of samples
below the pump intake. Well 33 was not selected for
attempts at arsenic remediation because elevated arsenic
concentrations were not detected. In Wells 02, 05, and
36, elevated arsenic concentrations were detected in
water from individual zones near the bottom of the wells
(Appendix 4 and 5). Well 02 was excluded from attempts
at arsenic remediation because the pumping water level
was too deep to allow relocation of the pump intake.
Data collected during a two-well (Wells 05 and 36)
investigation of arsenic remediation by well modification
are presented in Appendix 6.
Pump Relocation
Two of the 11 selected wells were selected for repeated
sampling to determine the effects of pump intake
relocation on water quality and well yield. In Wells 05
and 36, the pump was moved up to all positions in blank
sections of casing that were at least 100 feet below the
pumping water level. The pump was moved three times
in Well 05 and two times in Well 36. In Well 05, the
initial pump intake setting (dO) was at 640 feet below
land surface. The pump intake was moved to (dl)
610 feet, (d2) 560 feet, and (d3) 505 feet below land
surface (Figure 27). In Well 36, the initial pump intake
setting (dO) was at 670 feet. The pump intake was moved
to (dl) 650 feet and (d2) 590 feet below land surface
(Figure 28). For each pump location, determinations of
flow contribution and depth-dependent water quality
were repeated to evaluate changes in well dynamics.
For Well 05, the well-head arsenic concentration
at intake location dO was 10.9 ug/L (Figure 27). At
intake locations dl, d2, and d3, well-head arsenic
concentrations were less than 10 ug/L (8.1 ug/L,
6.5 ug/L, and 7.4 ug/L, respectively; Figure 27). For
Well 36, the well-head arsenic concentration at intake
location dO was 16.5 ug/L (Figure 28). At intake location
dl, the well-head arsenic concentration increased
slightly to 18.8 ug/L (Figure 28). At intake location d2,
well-head water quality showed much improvement,
with arsenic concentrations of only 2.6 ug/L (Figure 28).
Both wells showed short-term improvements in
water quality as the pump was moved to the highest
locations in the well. In Well 05, arsenic concentration
decreased by about 32 percent and well yield decreased
by 12 percent (Figure 27). In Well 36, the arsenic
concentration at the well head decreased by 84 percent
and well yield increased by 13 percent (Figure 28).
Arsenic concentrations at the well head mostly
decreased as the pump intake was moved farther
from the contaminated zone. However, all well-head
measurements described in this report were collected
after short periods (hours) of continuous pumping. At
Well 36, well-head samples at intake location d2 were
recollected after several days of continuous pumping to
determine if improvements in water quality persisted.
Analysis of these samples revealed that the improvement
in well-head water quality was only temporary; the well-
head arsenic concentration increased almost a full order
of magnitude from 2.61 ug/L to 20.6 ug/L (Figure 28).
Well-head water-quality samples, as well as field
measurements of specific conductance and pH, indicate
that the well was producing a greater proportion of water
from the deepest perforated zones when the well-head
sample tested at 20.6 ug/L than when the sample tested
at 2.6 ug/L (Figure 28). These results are similar to those
of Bexfield and Anderholm (2002), who discovered that
prolonged pumping of some public-supply wells in parts
of the Middle Rio Grande Basin resulted in increased
contribution of deeper water. Arsenic concentrations
in produced water also may fluctuate with seasonal
or prolonged changes in aquifer or zonal water levels
(Focazio et al., 2000). Izbicki et al. (2005) found that
increases in well-head chloride concentrations can result
from increased production from deeper zones over
time. This evidence confirms that zonal contributions
and well-head conditions can fluctuate substantially
over relatively short time periods (months) and long
time periods (decades) as a result of increased pumping
duration or frequency in a well field. The effect of
-------
extensive and seasonal pumping on well-head arsenic
concentrations is a subject that requires further study.
Zonal Isolation
The main objective of zonal isolation in this study was
to eliminate production from all zones that contribute
water of elevated arsenic concentrations. If this well-
modification method is successful, the concentration at
the well head should not exceed 10 ug/L (assuming that
arsenic concentrations in water from producing zones
remain constant over time). Variability in well-head
samples over time also should be lessened by eliminating
production from zones that contribute elevated arsenic
concentrations.
Elevated arsenic concentrations were detected at the
bottom of Wells 05 and 36 after every relocation of the
pump intake (Figures. 27-28). The depth-dependent
water-quality and flow-contribution data were integrated
to estimate the arsenic concentrations coming from each
perforated interval in Wells 05 and 36 (Figures. 27-28).
These estimated zonal arsenic concentrations, which
are listed on the gamma-ray logs in Figures 27-28, are
not true mass-balance calculations but semiquantitative
interpretations of zonal water quality; the precision
of data collection and analysis methods used in this
study was not sufficient for mass-balance calculations
on constituents measured in very small concentrations
(Ug/L).
The two deepest zones in Well 05 (620-677 feet below
land surface) were suspected of contributing elevated
arsenic concentrations to the well (Figure 27). The
shallower of the two zones was about 10 feet thick
and was suspected of producing water with arsenic
concentrations of about 20 ug/L (Figure 27). The deeper
zone was about 40 feet thick and was suspected of
producing water with arsenic concentrations greater than
60 ug/L (Figure 27). Only the deepest zone in Well 36
(648-658 feet, Figure 28) was suspected of contributing
elevated arsenic concentrations to the well. This 10-foot
sandstone was suspected of contributing water with
arsenic concentration greater than 60 ug/L (Figure 28).
Though Wells 05 and 36 were considered good
candidates for attempts at zonal isolation, Well 36 was
selected because of maximum potential for successful
^
s
g
ri
S
GO
cS
^-
GO
12%
7.6%
12%
H
NO
42%
Q = 249 ฑ16 gpm
w EXPLANATION
- V Pumping water level
dO^ Pump intake location
_ 10% showing percent
flow contribution
58% Percent of well yield
~ 42% coming from above
and below the pump
. 442 6.92 1.7 67
- 453 8.24 2.3 67
1 460 8.16 2.5 68
- 466 8.32 2.9 69
A 559 8.46 10.9 73
- 716 8.78 28.3 85
! 1,116 8.92 63.1 114
S
n I**
g
jc
GO
4.7%
16%
-at
NO
36%
17%
Q = 233 ฑ15 gpm
_
T
- 435 6.68 1.2 64
_ 428 7.95 1.8 66
- 441 7.92 1.7 66
1 446 7.96 1.8 66
^ 515 8.18 8.1 70
588 8.56 27.7 66
674 8.75 36.5 66
-
~ 901 8.76 52.0 85
g
I ^
3?
'-
^
*-
29%
NQ
72%
-28%
9.2%
5.2K
13%
Q = 246 ฑ16 gpm
_
W
_ 551 8.21 1.6 67
-
- 453 8.35 1.7 66
.514 8.48 6.5 68
869 8.88 34.4 81
-
844 8.88 31.9 78
-
~ 732 8.86 26.4 66
17%
58%
-
13%
7.0%
3.8%-
18%
Q = 220 ฑ14 gpm
445 7.97 1.6 67
537 8.61 7.4 69
855 8.66 26.7 88
1,003 9.07 40.3 94
995 9.15 39.5
8.85 38.4 96
20 40 60 80
NATURAL GAMMA RAY,
IN API UNITS
SC 1pH As Cr
Intake depth at do = 640
November 9, 2005
SC 1pH As Or
Intake depth at d1 = 610
November 17, 2005
SC 1pH As Cr
Intake depth at 02 = 560
January 13, 2006
SC 1pH As Cr
Intake depth at d3 = 505
January 20, 2006
Figure 27. Results of pump intake relocation in Norman Well 05. The final location (d3) resulted in a 32 percent
decrease in well-head arsenic concentration and a 12 percent decrease in production rate. Concentration
and field water property data in green are from well-head samples; those in black are from depth-dependent
samples at the indicated depth. Concentrations in red on the natural gamma ray log are estimated arsenic
concentrations in produced water from perforated intervals [Q, production rate in gallons per minute;
SC, specific conductance in microsiemens per centimeter; As, dissolved arsenic in micrograms per liter;
Cr, dissolved chromium in micrograms per liter; u.g/L, micrograms per liter; API, American Petroleum
Institute; gpm, gallons per minute; NQ, not quantifiable; %, percent].
-------
350
700
0 20 40 60 80
NATURAL GAMMA RAY,
IN API UNITS
Q = 240ฑ15gpm
r
448 7.75 0.49 57
~
447 7.75 0.43 57
~
~
-
~ 469 7.82 1.3 55
-
_
_
_
-
469 7.88 2.7 67
~ ~
.539 8.24 16.5 84
I 520 8.18 11.0 80
1 35
1 ป
c\i
OJ
n
'
gS
CM
-s
0
Q = 258ฑ17gpm
-
I
-
- 453 7.73 0.44 59
-
_
_
_ 493 8.12 2.7 78_
_
-
~ 508 8.27 6.7 82
*546 8.55 18.8 9f
-854 9.12 62.8 123
- 839 8.94 58.0 122
}ฃ
*~
!
M
m
"
ซQ%
60%
35
SI
35
8
Q = 272ฑ18gpm
-
I
-
- 453 7.26 0.48 58^
-
I 447 7.63 0.52 57_
A 456 7.39 2.6 57
- 461 7.74 1.4 50^
_
-
- 474 7.84 2.6 54
- 540 8.58 15.7 5fr
EXPLANATION
V Pumping water level
dฐA Pump intake location
_ 10., Perforated interval _
showing percent
flow contribution
40% Percent of well yield
gQ^ coming from above
and below the pump ~
-
~
~
Well-head sample only
-
_
A 567 8.48 20.6 9t
_
_
-
-
~
-
SC 1pH As Cr SC 1pH As Cr SC 1pH As Cr SC 1pH As Cr
Intake depth at dO = 670 Intake depth at d1 = 650 Intake depth at d2 = 590 Intake depth at d2 = 590
October 2004 (flow) September 2005 November 2005 January 2006
June 2005 (water quality)
Figure 28. Results of pump intake relocation in Norman Well 36. Concentration and field water property data in
green are from well-head samples; those in black are from depth-dependent samples at the indicated
depth. The final location (d2) resulted in an 84 percent decrease in well-head arsenic concentration and a
13 percent increase in production rate. However, the improvement in water quality was only temporary
and the well-head arsenic concentration increased to 20.6 mg/L after several days of production.
Concentrations in red on the natural gamma ray log are estimated arsenic concentrations in produced
water from perforated intervals [Q, production rate in gallons per minute; SC, specific conductance in
microsiemens per centimeter; As, dissolved arsenic in micrograms per liter; Cr, dissolved chromium in
micrograms per liter; iig/L, micrograms per liter; API, American Petroleum Institute; gpm, gallons per
minute; NQ, not quantifiable; %, percent].
remediation and the minimum potential for substantial
loss of production.
A retrievable bridge plug was installed in Well 36 in
June 2006 to isolate the suspect zone from production
(Figure 29). A retrievable bridge plug is an inflatable
packer with a valve head attached to the mandrel to
allow for setting and retrieving from a fixed position
in the well. The bridge plug was lowered to a depth of
640 feet from land surface and hydraulic pressure was
used to inflate the packer element and seal the bridge
plug against the well casing. After the packer inflation
was confirmed, the bridge plug and valve head were
released from the pipe string by a specialized overshot
tool and the pipe was removed from the well. With the
plug in place, the bottom 50 feet of the well was sealed
off and no obstructions were present in the upper part of
the well.
The pump was installed with the intake at about 600 feet
below land surface, or about 40 feet above the bridge
plug. The well was pumped continuously for about
96 hours while a YSI600XLM water-quality sonde
recorded specific conductance, pH, water temperature,
and dissolved oxygen concentration at the well head
(Figure 30). Well yield also was recorded (Figure 30).
Well-head trace elements (including arsenic by ICP-MS)
and major-ion samples were collected daily.
Well yield was about 220 gallons per minute, arsenic
concentration was 18.3 ug/L; pH was about 8.2 standard
units; and specific conductance was about 510 us/cm
in the first hour of pumping (Figure 30). After about
one day (1440 minutes) of pumping, the well yield
(210 gallons per minute), arsenic concentration
(20 ug/L), and pH (8.42 standard units) had stabilized
(Figure 30). Specific conductance fluctuated from 550
to 510 us/cm (Figure 30) for the following 3 days.
Dissolved oxygen concentration stabilized at 5.6 mg/L
(60.0 percent saturation) and water temperature
stabilized at about 18.5 degrees Celsius. The results
of this brief test indicate that, to obtain results most
-------
350
400
UJ
^450
w
Q
5 500
UJ
00
Si 550
UJ
D 600
650
700
40% ,
16%-^
Q = 272ฑ18gpm
453 7.26 0.48 58-
447 7.63 0.52 57
456 7.39 2.61 57-
461 7.74 1.4 50-
474 7.84 2.6
54-
540 8.58 15.7 56^
EXPLANATION
V Pumping water level -
d2A Pump Intake location
1 no/ Perforated interval
showing percent
flow contribution
40% Percent of well yield
60% coming from above
and below the pump
Well-head sample only
. 567 8.48 20.6 91 -
20 40 60 80
NATURAL GAMMA RAY,
IN API UNITS
SC 1pH As Cr SC 1pH As Cr
Intake depth at d2 = 590
January 2006
Intake depth at d2 = 590
November 2005
00
39%
~
240ฑ16gpm
555 8.44 20.2 89
SC 1pH As Cr
Intake depth = 600
June 2006
Figure 29. Results of attempted zonal isolation in Norman Well 36 by using a retrievable bridge plug. Concentration
and field water property data in green are from well-head samples; those in black are from depth-dependent
samples at the indicated depth. The placement of the plug had little effect on well-head water quality
or well yield [Q, production rate in gallons per minute; SC, specific conductance in microsiemens per
centimeter; As, dissolved arsenic in micrograms per liter; Cr, dissolved chromium in micrograms per
liter; (o,g/L, micrograms per liter; API, American Petroleum Institute; gpm, gallons per minute; NQ, not
quantifiable; %, percent].
representative of true production conditions, the Norman
wells should be pumped for at least 24 hours prior to
investigations of water quality and flow contribution
with depth.
The water-quality logging ended after nearly 4 days,
when the well had to be shut down after weekend
rainfall lowered water demand. The well was rested over
the weekend and restarted on Monday, June 19, 2006.
After 3 days of continuous pumping, the well discharge
was rerouted from the distribution pipe to a waste blow-
off prior to tracer-pulse velocity profiling on Thursday,
June 22, 2006. Depth-dependent samples were not
collected.
Unfortunately, the installation of the bridge plug in
Well 36 had no effect on well-head water quality.
Compared to the well-head sample collected in January
2006, specific conductance and concentrations of arsenic
and chromium each decreased by only 2 percent after
installation of the bridge plug (Figure 29). The well yield
estimate decreased by about 12 percent (Figure 29).
Flow contribution percentages for each perforated
interval changed little from measurements made in
November 2005. The only substantial change in flow
contribution was measured in the perforated interval
(605-640 feet) just above the bridge plug (Figure 29).
Apparently, this zone began producing more water to
compensate for the production lost from the perforated
interval below the pump intake. Cement-bond at the
depth of the plug was good, so annular communication
between zones above and below the plug is unlikely.
-------
The placement of the bridge plug assumed that the
isolated zone was not in close hydraulic connection
with the producing zone just above the bridge plug.
Although this assumption may be valid for the period
of testing (Figure 30), this assumption is probably
not valid over periods of years and decades. If the
mudstone (640-645 feet, Figure 29) above the suspected
contaminated zone is not laterally continuous or
impermeable near the well, water from the suspected
contaminated zone may be entering the well through the
perforated zone just above the bridge plug. However,
if the zones were hydraulically connected, mixing with
relatively uncontaminated water in the upper zone
should have had some mitigative effect on well-head
arsenic concentration.
A more probable explanation of why well-head water
quality remained the same is that the stretch factor
applied to the depth-dependent samples may have been
too great. If in reality minimal hose stretch occurred
during sample runs, the depth of the suspected arsenic-
contaminated water could have been overestimated by
as much as 13 feet. The arsenic-contaminated water
responsible for degradation of well-head water quality
may originate from the perforated sandstone just above
the bridge plug (605 to 640 feet, Figure 29). Therefore,
the bridge plug may have been placed too deep to
exclude the arsenic-contaminated water from production.
City of Norman Well 36
PH
Specific
conductance
EXPLANATION
Arsenic sample
Well yield
- pH
Specific conductance
Day 3
Day 4
8.50
8.30
8.10
7.90
7.70
1440
2880
PUMPING DURATION, IN MINUTES
4320
7.50
5760
Figure 30. Log of well yield and selected well-head water-quality constituents at Norman Well 36 during an attempt at
zonal isolation by using a retrievable bridge plug.
-------
9.0
Summary
The City of Norman, Oklahoma, is one of many
municipalities in the United States that is affected by a
change in the EPA's National Primary Drinking Water
Regulations that reduced the arsenic MCL from 50 ug/L
to 10 ug/L in 2006. The City of Norman depends on
ground-water from the Central Oklahoma (Garber-
Wellington) aquifer, a multilayered sandstone, siltstone,
and mudstone aquifer. Arsenic (and the associated metals
chromium, selenium, and uranium) has been identified as
a naturally occurring contaminant in the aquifer.
Historical arsenic concentrations of produced water from
32 active Norman public-supply wells ranged from less
than 1 ug/L to 232 ug/L. Based on maximum detected
arsenic concentrations in well-head samples, 11 of these
wells could be deemed noncompliant under the old
MCL of 50 ug/L arsenic. Of the 21 remaining wells,
10 additional wells, which account for about one-third
of the total well-field production capacity, likely will
be deemed noncompliant under the new arsenic MCL.
Through 2003, two thirds of the wells in the Norman
well field had produced at least one well-head sample
with arsenic concentration greater than 10 ug/L.
The Norman well field was thought to be well-suited for
the zonal-isolation strategy because (1) most Norman
public-supply wells have a cement-annulus and gun-
perforated openings, and (2) producing sandstone
zones are commonly separated or compartmentalized
by thick mudstones. The best candidates for successful
remediation by zonal isolation are those wells that
have (1) marginal well-head arsenic concentrations
(near 10 ug/L), (2) wide variation in well-head arsenic
concentrations, and (3) high water-production rates
(greater than 200 gallons per minute). These wells are
most likely to benefit from isolation of a single, high-
arsenic zone and are the least likely to suffer from loss of
production from that zone.
Based on historical well-head samples, some Norman
wells with marginal arsenic concentrations were
suspected of producing water from some zones with
acceptably low arsenic concentrations and some zones
with unacceptably high arsenic concentrations. If zones
with elevated trace-element concentrations can be
identified and sealed off from production, concentrations
measured at the well head may be decreased to meet
drinking-water regulations. To determine which wells
were possible candidates for arsenic remediation by
well rehabilitation, though, the flow contribution and
water quality of each producing zone was measured in
individual wells.
The water-quality data collected by the USGS well
profiler were extremely useful as a qualitative tool for
identification of zones that may degrade water quality
in the Norman wells. The depth-dependent sampling
method can identify the depth in the well bore at which
water becomes unsuitable for public supply (exceeds
the MCL), even without any data on flow contribution.
The USGS well-profiler method, as compared to
traditional methods, can be considerably less expensive
and requires less down-time of the well. In terms of data
quality, the most important advantage of the USGS well
profiler is that all data collection is performed under true
production conditions.
As part of the investigation of changes in water quality
with depth in the Norman area (southern Central
Oklahoma aquifer), an undeveloped site in Norman
was selected for drilling, logging, coring, and water
sampling in a test hole similar to that of earlier studies.
The selected test-hole site was in northern Norman
near the Little River. The test hole, referred to as the
arsenic test hole, was 728 feet deep and penetrated about
50 feet of the Hennessey Group, and nearly half of the
total thickness of the Garber Sandstone and Wellington
Formation.
Rock material was sampled by coring from 302 to 536,
568 to 598, 615 to 636, 640 to 652, and 668 to 686 feet.
Most of the red sandstones in the core were made up of
very-fine to fine-grained sand that was moderately well
to well sorted with respect to framework grains. The
sandstones also contained red mud (matrix composed
of clay and silt-sized mineral matter) between the
framework grains. Thin to moderately bedded layers of
conglomerate were present in the core and contained
clasts of dolomite and mudstone. Locally, mudstone
layers contained features that were indicative of soil
forming episodes during the Permian period (Permian
paleosol formation). Evidence for secondary iron
mobilization was present in the sandstone, conglomerate,
and mudrock preserved in the core.
Ground-water quality samples were analyzed from
seven predominantly sandstone zones (ranging from
12 feet to 40 feet in thickness) in the test hole. Arsenic
concentrations exceeded the MCL of 10 ug/L in all zones
where pH was greater than 8.5 and specific conductance
was greater than 600 uS/cm. Sandstone Zones 2 (416-
456 feet) and 3 (488-502 feet) were separated by only
32 feet but had different water types. The 52H of samples
from the test hole indicated a substantial change in
supposed water age from Zone 2 (younger) to Zone
-------
3 (older). This gap between younger and older water
corresponds to the gap between detected and non-
detected arsenic in zonal water samples.
The transition in water quality and supposed water
age from Zone 2 to Zone 3 could be an indication that
the intervening mudstone is a regional barrier to the
vertical flow of ground water. Alternatively, the contrast
could mean that zones below a depth of 460 feet are
richer in exchangeable clays. The contrast in water
quality between Zones 2 and 3 also could be related to
the presence of a basal carbonate-clast conglomerate
(represented by a zone of increased resistivity) in
Zone 2. According to one study, conglomerates in the
Central Oklahoma aquifer contain large concentrations
of dolomite, arsenic, and iron in the solid phase relative
to the other lithofacies in the aquifer system. If dolomite
supply or arsenic availability are limiting factors in
the chemical evolution of water when it reaches this
depth, the presence of the conglomerate could accelerate
arsenic release.
Eleven wells and one test hole were sampled to describe
changes in water quality and estimated water age
with depth in the Norman well field. Earlier studies
determined a relation between 52H and water age
determined from tritium and radiocarbon dating in
the Central Oklahoma aquifer. Though the relation is
not perfect, water age increases with decreasing 52H.
According to this relation, the youngest water was found
in Wells 18, 02, and the shallowest sampled zones of the
arsenic test hole. The oldest water sampled was found in
Well 07 and intermediate sandstone zones of the arsenic
test hole. The ages of water in the test hole could range
from only a few hundred years before present to more
than 30,000 years before present. This wide range in
age, as compared to well samples, is contradictory to
ages expected from review of modeled flow paths and
could be more characteristic of the natural, undeveloped
flow system. Completed wells, after years of seasonal
pumping stresses, could develop a narrower age
signature due to mixing by intra-borehole flow between
zones when the well is not being used.
Approximate ages of water (times since recharge) in
wells are on the order of hundreds to tens of thousands
of years. When plotted in order from most proximal to
most distal (from the recharge area) along a typical flow
path, the historical arsenic data for these wells express
upward trends in minimum, median, and maximum
detected arsenic concentrations with distance along the
flow path. This finding validates the aquifer conceptual
model developed by the USGS NAWQA Program.
Well-head arsenic concentrations measured in this study
compare favorably with historical well-head samples
at each well. All well-head arsenic samples collected
in this study were within the range of historical well-
head concentrations. Most depth-dependent arsenic
samples also were within the range of historical well-
head concentrations. Only Wells 02 and 36 had depth-
dependent arsenic samples that were outside the range of
historical well-head concentrations.
Most of the selected Wells (06, 07, 13, 15, 18, 23,
and 31) showed elevated or near-elevated arsenic
concentrations at all depths in the well. For these wells,
well-modification techniques would be ineffective in
lowering well-head arsenic concentrations to less than
10 ug/L. Wells 02, 05, 33, and 36, however, showed
some potential for successful application of well
modification techniques for arsenic remediation. In Wells
02, 05, and 36, elevated arsenic concentrations were only
detected in depth-dependent samples from the bottom
of the well. In Well 33, elevated arsenic concentrations
were not detected at any depth.
Wells 05 and 36 were selected for repeated depth-
dependent sampling to determine the effects of pump
intake relocation on water quality and well yield. In
Well 05, the initial pump intake setting was at 640 feet
below land surface. The pump intake was moved to 610,
560, and 505 feet below land surface. In Well 36, the
initial pump intake setting was at 670 feet below land
surface. The pump intake was moved to 650 and 590 feet
below land surface. Both wells showed improvements
in water quality as the pump was moved to the highest
locations in the well. In Well 05, arsenic concentration
decreased by about 32 percent and well yield decreased
by 12 percent. In Well 36, the arsenic concentration at
the well head decreased by 84 percent and well yield
increased by 13 percent. However, after several days
of continuous pumping, additional samples from well
36 indicated that the improvement in well-head water
quality was only temporary. To obtain results most
representative of true production conditions, the Norman
wells should be pumped for at least 24 hours prior to
investigations of water quality and flow contribution
with depth.
The main objective of zonal isolation in this study was
to eliminate production from all zones that contribute
water of elevated arsenic concentrations. Only the
deepest zone in Well 36 (648-658 feet) was suspected
of contributing elevated arsenic concentrations (greater
than 60 ug/L) to the well. A retrievable bridge plug was
installed in Well 36 to isolate the suspect zone from
production. Unfortunately, the installation of the bridge
plug in Well 36 had no effect on well-head water quality.
The bridge plug may have been placed too deep to
exclude the arsenic-contaminated water from production.
-------
10.0
Selected References
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Becker, C. J. Comparison of ground-water quality in
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Bexfield, L. M., and Anderholm, S. K. Spatial patterns
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Christenson, Scott. Ground-water-quality assessment
of the Central Oklahoma aquifer - Summary of
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Christenson, Scott and Havens, J. S., Eds., Ground-
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Geological Survey Water-Supply Paper 2357-A, 1998,
179 p.
Christenson, S. C., Morton, R. B., and Messander,
B. A. Hydrogeologic maps of the Central Oklahoma
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Christenson, Scott, Parkhurst, D.L. and Breit, G.
N. Summary of geochemical and geohydrologic
investigations of the Central Oklahoma aquifer. In
Ground-water-quality assessment of the Central
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Coplen, T. B. Reporting of stable hydrogen, carbon
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Ferree, D. M., Christenson, S. C., Rea, A. H., and
Messander, B. A. Ground-water-quality assessment of
the Central Oklahoma aquifer, Oklahoma-Hydrologic,
water-quality, and quality-assurance data, 1987-90;
U.S. Geological Survey Open-File Report 92-641,
1992, 193 p.
Focazio, M. J., Welch, A. H., Watkins, S. A., Helsel,
D. R., and Horn, M. A. A retrospective analysis on the
-------
occurrence of arsenic in ground-water resources of the
United States and limitations in drinking-water-supply
characterizations; U.S. Geological Survey Water-
Resources Investigations Report 99-4279, 2000, 22 p.
Garbarino, J. R. Methods of analysis by the U.S.
Geological Survey National Water Quality Laboratory
- Determination of dissolved arsenic, boron, lithium,
selenium, strontium, thallium, and vanadium using
inductively coupled plasma-mass spectrometry, U.S.
Geological Survey Open-File Report 99-093, 1999, 31 p.
Gonfiantini, R. Standards for stable isotope
measurements in natural compounds. Nature
271:534-536(1978).
Gossell, M. A., T. Nishikawa, R. T. Hanson, J. A.
Izbicki, M. A. Tabidian, and K. Bertine. Application of
flowmeter and depth-dependent water quality data for
improved production well construction. Ground Water
37 (5): 729-735 (1999).
Gromadzki, G. A. Outcrop-based gamma-ray
characterization of arsenic-bearing lithofacies in the
Garber-Wellington Formation, Central Oklahoma aquifer
(COA), Cleveland County, Oklahoma. Master's thesis,
Oklahoma State University, 2004, 232 p.
Ground Water Protection Council. The arsenic
issue: Cost effective alternatives for the small
community, 2005. http://www.gwpc.org/e-library/e-
library_documents/e_library_documents_general/
ArsenicAlternatives_GWPC2.doc. (accessed January 11,
2008).
Hart, D. L., Jr. Reconnaissance of the water resources
oftheArdmore and Sherman quadrangles, southern
Oklahoma; Oklahoma Geological Survey Hydrologic
Atlas 3, 1974, scale 1:250,000, 4 sheets.
Hem, J. D. Study and interpretation of the
chemical characteristics of natural water (3d ed.);
U.S. Geological Survey Water-Supply Paper
2254, 1989, 263 p.
Hess, A. E. A heat-pulse flowmeter for measuring
minimal discharge rates in boreholes; U. S. Geological
Survey Open-File Report 82-699, 1982, 40 p.
Hess, A. E. A wireline-powered inflatable packer for
borehole applications; U.S. Geological Survey Open-
File Report 93-485, 1993, 19 p.
Izbicki, J. A., Christensen, A. H., Hanson, R. T., Martin,
Peter, Crawford, S. M., Smith, G. A. U.S. Geological
Survey combined well-bore flow and depth-dependent
water sampler; U.S. Geological Survey Fact Sheet
196-99, 1999, 2 p.
Izbicki, J. A., A. H. Christensen, M. W. Newhouse, G.
A. Smith, and R. T. Hanson. Temporal changes in the
vertical distribution of flow and chloride in deep wells.
Ground Water 43 (4): 531-544 (2005).
Johnson, H. L., andDuchon, C. E., Atlas of Oklahoma
Climate; Norman, Okla., University of Oklahoma Press,
1995, 104 p.
Kendall, C., and T. B. Coplen. Distribution of oxygen-18
and deuterium in river waters across the United States.
Hydrological Processes 15 (7): 1363-1393 (2001).
Kenney, K. M. Outcrop-based lithofacies and
depositional setting of arsenic-bearing Permian red beds
in the Central Oklahoma aquifer, Cleveland County,
Oklahoma. Master's Thesis, Oklahoma State University,
2005, 299 p.
Keys, W. S. Borehole geophysics applied to ground-
water investigations; U.S. Geological Survey Techniques
of Water-Resources Investigations, book 2, chap. E2,
1990, 150 p.
Leve, G. W. Analysis of current meter data from wells
by flow-distribution curves. Groundwater 2 (2): 12-17
(1964).
McDonald, M. G., and Harbaugh, A. W. A modular
three-dimensional finite-difference ground-water flow
model; U.S. Geological Survey Techniques of Water-
Resources Investigations, book 6, chap. Al, 1988, 586 p.
Mosier, E. L. Briggs, P. H., Crock, J. G., Kennedy, K.
R., McKown, D. M., Vaughn, R. B., and Welsh, E. P.
Analyses of subsurface Permian rock samples from the
Central Oklahoma aquifer; U.S. Geological Survey
Open-File Report 90-456, 1990, 65 p.
Nkoghe-Nze, S. C. A reconnaissance study of controls
on aquifer quality in the Central Oklahoma aquifer,
Oklahoma. Master's Thesis, Oklahoma State University,
2002, 68p.
Parkhurst, D. L., Christenson, S. C., andBreit, G.
N. Ground-water-quality assessment of the Central
Oklahoma aquifer, Oklahoma - Geochemical and
geohydrologic investigations; U.S. Geological Survey
Water Supply Paper 2357-C, 1996, 101 p.
-------
Parkhurst, D. L., Christenson, S. C., and Schlottman,
J. L. Ground-water-quality assessment of the Central
Oklahoma aquifer, Oklahoma -Analysis of available
water-quality data through 1987; U.S. Geological
Survey Water-Supply Paper 2357-B, 1994, 74 p.
Pettijohn, F. J., Potter, P. E., and Siever, R. Sand and
sandstone; Springer-Verlag, New York, 1987; 553 p.
Piper, A. M. A graphic procedure in the geochemical
interpretation of water analyses; Transactions, American
Geophysical Union, v. 25, 1944, pp. 914-923.
Pollock, D. W. Documentation of computer programs
to compute and display pathlines using results from
the U.S. Geological Survey modular three-dimensional
finite-difference ground-water flow model. U.S.
Geological Survey Open-File Report 89-381, 1989, 49 p.
Reading, H. G. Fashions and models in sedimentology -
A personal perspective. Sedimentology 37: 3-9 (1987).
Rounds, S. A., and Wilde, F. D., Eds. Alkalinity and
acid neutralizing capacity; U.S. Geological Survey
Techniques of Water-Resources Investigations, book 9,
chap. A6, sect. 6.6, 2001, http://pubs.water.usgs.gov/
twri9A6/ (accessed April 3, 2003).
Schlottmann, J. L., and Funkhouser, R. A. Chemical
analyses of water samples and geophysical logs from
cored test holes drilled in the Central Oklahoma aquifer,
Oklahoma; U.S. Geological Survey Open-File Report
91-464, 1991, 58 p.
Schlottmann, J. L., Mosier, E. L., and Breit, G. N.
Arsenic, chromium, selenium, and uranium in the
Central Oklahoma aquifer. In Ground-water-quality
assessment of the Central Oklahoma aquifer, Oklahoma
- Results of investigations; Christenson, Scott, and
Havens, J. S., Eds.; U.S. Geological Survey Water-
Supply Paper 2357-A, 1998, pp. 119-179.
Schlottmann, J. L. "Naturally occurring arsenic in
the Central Oklahoma aquifer." In Proceedings of the
U.S. Geological Survey workshop on arsenic in the
environment, Denver, CO, February 21-22, 2001, 4 p.
Slejkovec, Z., J. T. vanElteren, and A. R. Byrne.
Analytica ChimicaActa 358: 51-60 (1998).
Smith, A. H., Claudia Hopenhayn-Rich, M. N. Bates,
H. M. Goeden, Irva Hertz-Picciotto, H. M. Duggan, R.
Wood, M. J. Kosnett, and M. T. Smith. Cancer risks
from arsenic in drinking water. Environmental Health
Perspectives 97: 259-267 (1992).
Sokolic, K. J. Arsenic occurrence in the Central
Oklahoma aquifer. Master's Thesis, University of
Oklahoma, 2003, 72 p.
Stollenwerk, K. G., Geochemical processes controlling
transport of arsenic in groundwater - A review of
adsorption. In Arsenic in groundwater: Geochemistry
and occurrence; Welch, A. H., and Stollenwerk, K. G.,
Eds.; Kluwer Academic Publishers: Boston, 2003; 34 p.
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of part 141, National interim primary drinking water
regulations): U.S. Code of Federal Regulations, Title 40,
Parts 100-149, revised July 1, 1986, p. 374.
USEPA. Analytical methods support document for
arsenic in drinking water, EPA/815-R-00-010. U.S.
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April 2, 2008, at htpp://epa.gov/safewater/arsenic/pdfs/
methods.pdf.
USEPA. Arsenic occurrence in public drinking water
supplies, EPA/815-R-00-023. U.S. Environmental
Protection Agency, 2000, 138 p.
USEPA. National primary drinking-water regulations;
Arsenic and clarifications to compliance and new source
contaminants monitoring: final rule. Federal Register 66,
no. 14, 2001, pp. 6876-7066.
Visher, G. S. Fluvial processes as interpreted from
ancient and recent fluvial deposits. In Primary
sedimentary structures and their hydrodynamic
interpretation; Middle ton, G. V., Ed., Society of
Economic Paleontologists and Mineralogists Special
Publication 40012, Tulsa, Oklahoma, 1965, pp. 116-132.
Welch, A. H., Watkins, S. A., Helsel, D. R., and Focazio,
M. J. Arsenic in ground-water resources of the United
States. U.S. Geological Survey Fact Sheet FS-063-00,
2000, 4 p.
Wilde, F. D., Radtke, D. B., Gibs, Jacob, and Iwatsubo,
R. T, Eds., National field manual for the collection of
water-quality data: U.S. Geological Survey Techniques
of Water-Resources Investigations, 1998, book 9, chap.
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Wilde, F. D. and Radtke, D. B., Eds., National field
manual for the collection of water-quality data: U.S.
Geological Survey Techniques of Water-Resources
Investigations, 1998, book 9, chap. A6, variously paged.
-------
Wood, P. R., and Burton, L. C. Ground-water resources
in Cleveland and Oklahoma Counties, Oklahoma.
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2 plates.
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flow on groundwater age distribution. Hydrogeology
Journal 15 (4): 633-643 (2007).
-------
_ _ _ EPA/600/R-09/036
11.0
Appendixes
1. Photographs of core from the Norman arsenic test hole, 2004
2. Description of core from the Norman arsenic test hole, 2004
3. Chemical analyses of ground-water samples and quality-assurance samples from the Norman arsenic test hole,
station number 351645097253801, in October 2004
4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for
arsenic remediation by well modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006
5. A-K. Illustrations of natural gamma-ray logs, open-interval logs, flow contribution, and water quality with depth
in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006
6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in
two selected public-supply wells, Norman, Oklahoma, 2005-2006
-------
Appendix 1. Photographs of core from the Norman arsenic test hole, 2004, showing depth, in feet below land surface, for
the top and bottom of core interval.
302'
Box 1 of 26
332'
Box 2 of 26
6'
Norman arsenic test hole
Norman arsenic test hole
-------
346'
Box 3 of 26
Box 4 of 26
Norman arsenic test hole
Norman arsenic test hole
-------
361'
Box 5 of 26
375'_
Box 6 of 26
P375'
Norman arsenic test hole
Norman arsenic test hole
-------
377'
Box 7 of 26
387'
Box 8 of 26
387'
'402'
Norman arsenic test hole
Norman arsenic test hole
-------
402'
Box 9 of 26
420'
Box 10 of 26
120'
430'
Norman arsenic test hole
Norman arsenic test hole
-------
430'
Box 11 of 26
442'
Box 12 of 26
'460'
Norman arsenic test hole
Norman arsenic test hole
-------
460'
Box 13 of 26
471'
Box 14 of 26
80'
Norman arsenic test hole
Norman arsenic test hole
-------
489'
Box 15 of 26
491'
Box 16 of 26
504'
Norman arsenic test hole
Norman arsenic test hole
-------
504'
Box 17 of 26
514'
Box 18 of 26
514'
Norman arsenic test hole
Norman arsenic test hole
-------
524'
Box 19 of 26
570'
Box 20 of 26
80'
Norman arsenic test hole
Norman arsenic test hole
-------
580'
Box 21 of 26
590'
Box 22 of 26
598'
Norman arsenic test hole
Norman arsenic test hole
-------
615'
Box 23 of 26
640'-
Box 24 of 26
652'
Norman arsenic test hole
Norman arsenic test hole
-------
670'
Box 25 of 26
678'
Box 26 of 26
86'
Norman arsenic test hole
Norman arsenic test hole
-------
Appendix 2. Description of core from the Norman arsenic test hole, 2004.
EXPLANATION
ripples, ripple laminations
cross bedding, troughs
low-angle cross bedding
laminations
poorly defined laminations
straight bounding surface of bed
irregular bounding surface of bed
diagenetic iron-crust, crenulations
root traces
calcite nodule or concretion (diagenetic, sand-size)
iron clot (diagenetic)
diagenetic reduction spot
gravel-size carbonate clast (transported caliche-like clast)
gravel-size mud clast (transported / rip-up clast)
conglomerate
sandstone
siltstone
mudstone
-------
Core Description, Norman arsenic test hole, Norman, Oklahoma
Logged by: S.T. Paxton
1 Depth below land surface,
infest
302'
Thickness
[Whole Indies I Fractions of Inch
Box# Draft Sheet #
303'
305'
not recovered
not recovered
310'
not recovered
SIS-
SIS'6"
317'
318' 1"
318'8"
not recovered
not recovered
322'
323'
48
irregular, curved bedding surfaces,
ripples, disintegrated mud dasts
conglomerate - irregular, curved
bedding surfaces
47
46,47 crumbly, soil-like character
46 root traces
1 46 root traces
-------
323'
325' 4"
327'
327' 10"
330'
332'
337'
339'
340'
342'
28 0 0
not recovered
not recovered
not recovered
37 0 0
3 o o_
not recovered
24 0 0
not recovered
1 46 laminated, wall cemented
45,46
1 45 cross beds, root traces
2 44,45
2 44
2 44
2 43 nearly unconsolidated
Page3cf18
-------
345'
350'
351 ' 4"
355' 3"
3561
360'
360;9"
363'
366' 3"
366' 7"
000
112 0 0
not recover!
not recover
47 0 0
d
57 0 0
d
24 0 0
39 0 0
4 0
2, 3
some shale dasts, sandstone is poorly
consolidated, some very fine sand size
iron oxide nodules
3 42 some reduction features
3,4 42 green (chemically-reduced) features
4 41,42
4 41
5 41
5 40,41
5 40
"ped"-like features, green (reduced)
green (reduced) zone
Page 4 of 18
-------
3661 7"
370'
not recovered
not recovered
Ol O
1TR1
24 0 0
00^
0 o 0
OOO ซ* o o
oฐoO
0771 : x w
380'
385'
386' 8"
3071 no* recover
388' 6"
not recover!
O ,",
O 0
o
116 0 0
I I
'-'
Hi
400
600
id
5 39, 40
6 39 conglomerate - cemented
7 ซg reduction spots and other
redoxymorphic fearturas throughout
38 39 reduction spots and other
redoxymorphic feartures throughout
3a reduction spots and other
redoxymorphic fearturas throughout
8 38
8 38 cemented mudstone
8 38
38
390'
-------
390'
not recovered
393'
395'
398' 8"
400' 2"
402'
404'
404' 6"
405'
not recovered
not recovered
not recovered
410'
412'
412'6"
412'9"
not recovered
37
37
8 36,37
36 vf
36 laminated, vfL-silt
36
36
35,36
35
35
laminated muddy sandstone with some
cross bedding
muddy sandstone with clasts
Page 6 of 18
-------
412' 9"
4151
416'
4181
4201
27 0 0
12 0 0
24 0 0
not recovered
425'
426' 1"
4291 4"
4301
not recovered
435'
9 34,35
9 34
9 34
10 33,34
10
large-scale cross sets, horizontal
laminations
10 33
,. purple sandstone, large-scale cross
"" &
11 32 large-scale cross s
-------
435'
438' 8"
not recovered
442'
4441
4451
24 0 0
not recovered
not recovered
450'
4521
454'
455' 5"
455'ir
Gปiปr 457' 1"
-- 457'7"
not recovered
not recovered
O
Wellington
Formation
11 31,32 large-scale cross sets
12 31
12
12
12
30,31
30
30
29 conglomerate - cemented
29 calcite nodules
conglomerate - cemented
29
29
conglomerate - cemented
calcite nodules
Page 8 of 18
-------
458' 6"
459' 5"
^~ .
*
11 0 0
"^^"^J^
17 0 0
^ -^
12
12
13
461' 7"
4631 4"
4671 4"
46911"
471'
4721
472' 10"
4731 4"
4741 7"
476' 10"
477' 6"
4791 3"
480'
48
not recovered
not recovered
not recovered
13
14
14
14
14
14
14
29 core depths overlapping with below
29 core depths overlapping with above
29
29
28,29 siltstone
28
no dear evidence tor paleosol
28 siltstone
27,28
27 crenulated iron laminations
27
27
27
27
27 siltstone
26, 27
conglomerate - cemented
ripples
-------
482'
483' 11"
485' 3"
485' 7"
488'
490'
491'
492' 6"
493'
496' 4"
*ง7:4ป
502'
504'
26 0 0
24
not recovered
18
not recovered
40
not recovered
15 26 siltstone
15 26
15 26 ripples
15 25 siltstone and mudstone
15
15
16
16
25 calcite nodules
6" overlap of core relative to depths on
core box
25
16 24,25 low-angle cross sets
24
24
23
20" recovery, no evidence for paleosol
22" recovery
-------
506'
508'
510'
512'
514'
516'
518'
520'
522'
524'
525' 7"
not recovered
24
24
17
0 0
0 0
0 0
3d
24
24
24
24
24
24
19
0 0
0 0
0 0
0 0
0 0
0 0
0 0
22"recoveiy
23"recovery
17 23
17 23
17 22 no clear evidence for paleosol
22
17 22 no clear evidence for paleosol
18 22 no clear evidence for palaosol
18 22 no clear evidence for paleosol
18 21
18 21
18 21
19 21
-------
525' 7"
20,21
530'
531'
532'
12 0 0
20 no iron dots
iron clots begin @ 532' - intervals of
chemical reduction 533' 6" to 535"
545'
36 0 0
19 19,20
535'
540'
19 19 iron clots
15,16,17,18,19
not cored
15,16,17,18,19
15,16,17,18,19
-------
550'
555'
560'
565'
570'
573' 4"
24 0 0
15,16,17,18,19
15,16,17,18,19
15,16,17,18,19
15,16,17,18,19
20 15 ripples
20 15 calcite nodule
-------
573' 4"
574'
579' 5"
580'
582'
589'1"
590'
not recovered
15
o
o
o
o
o o
O o (J (J
21
21
22
22
22
22
12
12
12
12
12
12
oalcite nodules
calclte nodules
13 trough cross bedding
13
13 iron nodules
13 iron nodules
13 iron nodules
13
conglomerate - cemented
conglomerate - cemented
cemented
cemented
cemented
Page14of18
-------
595' 2"
615'
617'
I 2 DO
22 0 0
not recovered
9,10,11,12
9,10,11,12
9,10,11,12
23 9
23 9
-------
8,9
625'
6251 4"
23
6,7,8
not recovered / not cored
6,7,8
not recovered
6,7,8
640'
-------
640'
Iff
4"
24 0 0
400
24 6
24 6
32" - not recovered
24 6
6451
6461 2"
648' 10"
649' 10"
650110"
14 0 0
12 0 0
12 0 0
24 5,6 trough cross beds
24 3,4
not cored
not cored
3.4
-------
6701
6771 3"
6781
4" - not recovered
9"- not recovered
10 0 0
13 0 0
o
25
25
2 large-scale cross beds
25 2 large-scale c
25
1 cross beds
26 1
26 1 conglomerate - cemented
681' 5"
-------
Appendix 3. Chemical analyses of ground-water samples and quality-assurance samples from the Norman arsenic test hole, station number
351645097253801, in October 2004
Zone
Zone 1
Zone 2
Date
Oct 9 2004
Oct 1 1 2004
Zones Oct 12 2004
Zone 4 Oct 13 2004
Zones Oct 15 2004
Zone 6 Oct 16 2004
Zone 7 Oct 17 2004
Specific
Depth to Depth to top Elevation Pumping conductance,
Quality bottom of of water- of land period prior field
assurance water-bearing bearing zone surface Flow rate to sampling (mS/cm at
Time sample type zone (feet) (feet) (feet) (gpm) (min) 25 ฐC)
1900 350 320 1,125 5.8 75 498
1900 Duplicate
1000 456 416 1,125 5.0 60 433
0900 502 488 1,125 5.1 75 474
1400 598 568 1,125 4.0 90 602
0900 636 615 1,125 6.0 85 644
1300 652 640 1,125 6.0 110 662
1700 686 668 1,125 5.8 70 769
pH,
field,
standard
units
7.65
7.71
8.76
8.97
8.90
9.02
9.02
Temper-
ature, air
13.5
16.2
9.3
22.2
15.7
20.1
25.5
Appendix 3. Chemical analyses of ground-water samples and quality-assurance samples
351645097253801, in October 2004, (continued)
Zone
Zone 1
Zone 2
Zone 3
Zone 4
Zone 5
Zone 6
Zone 7
Date
Oct 9 2004
Oct 1 1 2004
Oct 1 2 2004
Oct 1 3 2004
Oct 1 5 2004
Oct 1 6 2004
Oct 172004
Acid
neutralizing
Sodium capacity
Sodium adsorption Potassium Bicarbonate Carbonate (mg/L as
Time (mg/L) ratio (mg/L) (mg/L) (mg/L) CaCO3)
1900 19.5 .58 2.42 301.6 .5 248.2
1000 29.8 1.05 2.12 243.1 .5 200.2
0900 99.7 11.7 .821 270.6 6.9 233.5
1400 133 24.5 .601 322.7 16.8 292.9
0900 150 26.1 .658 344.1 15.1 307.6
1300 155 30.0 .766 374.4 17.5 314.3
1700 180 35.8 .660 379.4 24.5 352.3
Sulfate
(mg/L)
7.61
7.47
7.61
11.9
17.2
19.3
19.1
19.1
27.9
Chloride
(mg/L)
14.5
14.4
14.5
2.34
3.16
3.37
3.52
3.44
5.72
Temper-
ature, water
18.4
18.3
18.5
19.0
18.6
18.8
18.8
from the
Fluoride
(mg/L)
.28
.28
.28
.47
.83
1.27
1.28
1.17
1.35
Turbidity,
field
(NTU)
23.0
35.6
459
365
212
72.8
138
Norman
Bromide
(mg/L)
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
Barometric
pressure
(mm Hg)
737.1
729.1
732.3
733.9
726.5
732.1
725.3
arsenic
Iodide
(mg/L) (
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
Dissolved
oxygen,
field
(mg/L)
7.34
6.46
6.01
7.74
4.35
4.59
3.78
test hole
Dissolved
oxygen,
field
76.5
68.7
64.2
83.5
46.7
49.3
40.6
, station
Nitrite plus
Nitrite nitrate
mg/L as N) (mg/L as N)
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
.805
"
.531
.130
.142
.146
.285
.274
.265
.261
Calcium
(mg/L)
37.0
25.9
2.66
1.35
1.53
1.30
1.20
number
Ammonia
(mg/L as N)
<.100
^^H
<.100
E.046
<.100
<.100
<.100
<.100
.224
.213
Magnesium
(mg/L)
30.3
^^M
21.4
1.75
.542
.587
.443
.433
Ortho-
phosphate
(mg/L as P)
E.015
^^H
E.013
.020
E.019
.041
"
.040
.039
.051
.051
-------
Appendix 3. Chemical analyses of ground-water samples and quality-assurance samples from the Norman arsenic test hole, station number
351645097253801, in October 2004, (continued)
Aluminum Antimony
Zone
Zone 1
Zone 2
Zones
Zone 4
Zones
Zone 6
Zone 7
Date
Oct 9 2004
Oct 1 1 2004
Oct 122004
Oct 13 2004
Oct 152004
Oct 162004
Oct 172004
Time
1900
1000
0900
1400
1400
0900
1300
1700
(mg/L)
89
E31
E67
E46
E57
92
114
(mg/L)
<57
<57
<57
<57
<57
<57
<57
Arsenic Arsenate Arsenite
Dimethyl- Monomethyl-
arsinate arsonate Barium Beryllium
(mg/L) (mg/L as As) (mg/L as As) (mg/L as As) (mg/L as As) (mg/L) (mg/L)
<110 <10 <10
<110 E9 <10
E45 28 <10
E83 58 <10
67 54 <10
E73 52 <10
Appendix 3. Chemical analyses of ground-water samples and
35 1645097253801, in
Zone
Zone 1
Zone 2
Zones
Zone 4
Zones
Zone 6
Zone 7
Date
Oct 9 2004
Oct 1 1 2004
Oct 12 2004
Oct 13 2004
Oct 15 2004
Oct 162004
Oct 172004
Time
1900
1000
0900
1400
0900
1300
1700
Lead
(mg/L)
<50
<50
<50
<50
<50
<50
<50
Manganese
(mg/L)
E8
^^^m
15
E8
E5
^^H
E5
E5
E5
October 2004, (continued)
Molybdenum Nickel Selenium
(mg/L) (mg/L) (mg/L)
<30 <13 <100
<30 <13 <100
<30 <13 <100
<30 <13 E33
^HH
E9 <13 100
<30 <13 E93
E12 <13 E46
<20 <10
<20 <10
<20 <10
<20 <10
--
<20 <10
<20 <10
<20 <10
472 <13
279 <13
103 <13
104 <13
131 <13
135 <13
172 <13
quality-assurance samples from
Silver Strontium
(mg/L) (mg/L)
<7 910
<7 620
<7 73
^^_ 34
<7 33
<7 25
<7 26
Thallium Titanium
(mg/L) (mg/L)
<90 78
<90 28
<90 52
<90 31
<90 53
<90 88
<90 110
Boron Cadmium Chromium
(mg/L) (mg/L) (mg/L)
538 <13 30
272 <13 39
933 <13 80
1,420 <13 78
2,510 <13 79
2,600 <13 82
3,090 <13 101
the Norman arsenic test
Vanadium Zinc Uranium
(mg/L) (mg/L) (mg/L)
<33 229 <13
<33 165 <13
71 E17 <13
209 <57 <13
660 <57 14
597 <57 <13
510 <57 <13
Iron(ll), Iron,
Cobalt Copper field field Iron
(mg/L) (mg/L) (mg/L) (mg/L) (mg/L)
<10 <37 <.01 .02 E68
<10 <37 <.01 .01 E46
<10 <37 .04 .09 <117
<10 <37 <.01 .04 <117
^^^B 1 1 IHHHH
<10 <37 .08 .65 <117
<10 <37 <.01 .03 E52
<10 <37 <.01 <.01 E56
hole, station number
Deuterium/ Oxygen-18/ Organic
Protium ratio Oxygen-16 ratio carbon
(per mil) (per mil) (mg/L)
-34.0 -5.70 E.497
-36.9 -6.10 <.500
-42.0 -6.72 1 .20
-42.8 -6.79 <.500
-41.8 -6.75 <.500
-41.6 -6.68 E.486
-40.6 -6.62 <.500
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. Shaded rows denote quality-assurance samples [23p,
packer tests in Well 23; mg/L, milligrams per liter; |o,g/L, micrograms per liter; gpm, gallons per minute; %, percent; min, minutes;
uS/cm at 25ฐC, microsiemens per centimeter at 25 degrees Celsius; ฐC, degrees Celsius; NTU, Nephelometric Turbidity Units; mm Hg,
millimeters of mercury; E, estimated below quantitation limit; <, less than quantitation limit; --, no data].
Well USGS Station name Quality Date Time Sampling Depth to Depth to top Elevation
station number assurance depth bottom of water of water- of land
sample (feet) bearing zone bearing surface
type (feet) zone (feet)
(feet)
Flow rate
(gpm)
Pumping
period prior
to sampling
(min)
Specific
conductance,
field
(uS/cm at
25 ฐC)
pH, Temperature, Temperature,
field, air water
standard (ฐC) (ซC)
units
02
02
02
02
02
02
02
02
02
02
02
02
02
02
02
02
02
02
02
02
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
Blank
Duplicate
Duplicate
Duplicate
Mar 22 2005
Mar 22 2005
Mar 24 2005
Mar 24 2005
Mar 24 2005
Mar 24 2005
Mar 24 2005
Mar 22 2005
Mar 24 2005
Mar 22 2005
Mar 22 2005
1000
1001
0900
0900
0930
1030
1300
1130
1230
1030
1030
420
420
470
530
well head
560
600
615
615
1128
1128
1128
1128
1128
1128
1128
1128
1128
1128
1128
434
7.46
12.9
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
351426097232201
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
22 ADD 1
Duplicate
Replicate
Duplicate
Duplicate
Jan 26 2006
Jan 26 2006
Jan 26 2006
Jan 26 2006
Jan 26 2006
Jan 26 2006
Jan 26 2006
Jan 26 2006
Jan 26 2006
1200
1200
1300
1300
1230
1230
1400
1030
1030
470
470
495
495
525
525
well head
615
615
1128
1128
1128
1128
1128
1128
1128
1128
476
506
526
659
625
659
__
445
435
7.93
7.97
8.33
7.85
7.89
7.60
14.3
18.1
23.3
8.0
22.4
8.9
17.5
444
7.77
580
1,006
8.51
8.79
17.8
05
05
05
05
05
05
05
05
05
05
05
05
05
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
Duplicate
Replicate
Duplicate
Duplicate
Duplicate
Dec 20 2004
Dec 21 2004
Dec 20 2004
Dec 21 2004
Dec 21 2004
Dec 21 2004
Dec 21 2004
Dec 20 2004
Dec 20 2004
Dec 20 2004
Dec 20 2004
Dec 20 2004
Dec 20 2004
1400
1030
1600
1100
1100
1200
1201
1500
1500
1430
1200
1200
1300
well head
435
470
500
500
500
500
550
550
605
635
635
660
1161
1161
1161
1161
1161
1161
1161
1161
483
438
435
435
8.45
8.14
8.30
8.36
19.0
9.4
19.0
9.4
17.6
447
8.28
19.3
1161
1161
447
442
8.31
8.33
19.2
18.3
1161
595
8.91
18.3
05
05
05
05
05
05
05
05
05
05
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
22 DDA 1
Duplicate
Duplicate
Duplicate
Nov 9 2005
Nov 9 2005
Nov 9 2005
Nov 9 2005
Nov 9 2005
Nov 9 2005
Nov 9 2005
Nov 9 2005
Nov 9 2005
Nov 9 2005
1000
1200
1200
1100
1300
1600
1600
1500
1500
1400
470
500
500
550
600
well head
well head
630
630
660
1161
1161
442
453
6.92
8.24
1161
1161
1161
460
466
559
8.16
8.32
8.46
17.6
1161
716
8.78
1161
1,116
8.92
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
Sampling
depth
(feet)
Turbidity,
field
(NTU)
Barometric
pressure
(mm Hg)
Dissolved
oxygen,
field
(mg/L)
Dissolved
oxygen,
field
(%)
Calcium,
filtered
(mg/L)
Magnesium,
filtered
(mg/L)
Sodium,
filtered
(mg/L)
Sodium
adsorption
ratio
Potassium,
filtered
(mg/L)
Bicarbonate,
unfiltered
(mg/L)
Carbonate, Acid neutralizing
unfiltered capacity
(mg/L) (mg/L as
CaCO3)
02
02
02
02
02
02
02
02
02
02
02
420
420
470
530
well head
560
600
615
.71
.59
.74
.35
.53
1.27
1.47
724.3
^m
724.9
725.2
725.2
722.8
725.2
722.8
<.167
13.0
<.300
11.0
E.753
67.0
5.99
54.1
13.7
13.6
13.4
16.7
16.1
16.7
11.5
11.4
11.1
13.8
13.3
13.8
75.5
82.5
88.6
108
104
109
3.31
"
3.64
3.99
4.33
4.73
4.64
4.78
1.85
1.76
1.73
1.92
1.86
1.88
263.3
^m
285.3
303.7
315.8
310.7
369.9
377.3
1.0
1.1
1.3
1.5
1.2
1.5
1.5
217.7
^m
235.9
251.4
261.5
310.7
306.0
312.0
739.4
739.4
9.13 96.2
6.91
6.27
8.60
8.59
8.63
8.39
7.88
5.18
4.63
75.1
75.2
75.2
74.8
79.5
118
136
4.14
4.14
4.13
4.16
4.56
8.27
10.0
1.63
1.58
1.64
1.61
1.57
1.15
1.10
204.2
05
05
05
05
05
05
05
05
05
05
05
05
05
well head
435
470
500
11.4
4.25
2.24
5.55
722.3
728.8
722.3
728.8
6.30 61.6
7.24
9.53
7.03
7.08
5.34
7.56
5.27
5.26
97.3
81.5
86.9
87.9
6.69
4.79
6.04
6.10
1.13
1.98
1.17
1.17
286.0
269.2
273.5
273.9
240.6
223.7
229.1
227.1
500
500
4.72
660
18.2
722.3
5.47
4.06
130
10.3
.998
321.2
17.3
292.5
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
Sampling
depth
(feet)
Sulfate,
unfiltered
(mg/L)
Chloride,
unfiltered
(mg/L)
Fluoride,
unfiltered
(mg/L)
Bromide,
unfiltered
(mg/L)
Iodine,
unfiltered
(mg/L)
Nitrite,
unfiltered
(mg/L as N)
Nitrite plus nitrate,
unfiltered
(mg/L as N)
Ammonia,
unfiltered
(mg/L as N)
Orthophosphate,
unfiltered
(mg/L as P)
Aluminum,
filtered
(ug/L)
Antimony,
filtered
(ug/L)
Arsenic,
filtered
(ug/L)
02
02
02
02
02
02
02
02
02
02
02
420
420
470
530
well head
560
600
615
615
<1.00
12.3
"
14.7
16.5
17.3
24.4
24.4
25.8
25.8
E.15
4.64
"
5.96
6.76
7.36
11.5
11.1
11.8
<.50
E.28
|j^
E.24
E.24
E.24
E.19
E.21
E.21
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
E.032
E.017
.350
<.100
<.100
<.100
.347
.334
.327
.298
.298
.278
<.100
.311
<.100
<.100
.334
<.100
E.009
E.008
E.013
E.014
E.014
E.013
E.013
E.013
E.013
E.013
E81
138
217
98
111
130
102
108
E.19
<1.00
<57
<57
<57
<57
<57
<57
<57
<57
470
12.8
4.20
4.25
4.17
3.88
3.93
15.2
59.9
<.250
"
<.250
<.250
<.250
<.250
<.250
<.250
<.025
<.100
.288
<.100
E.016
<.025
<.025
<.025
<.025
<.025
<.025
<.100
<.100
<.100
<.100
<.100
<.100
.767
5.86
2.93
2.09
2.18
2.04
2.03
3.05
E.42
E.31
E.26
E.30
E.28
E.28
E.29
3.23
2.98
2.98
13.7
E.38
E.39
E.40
E.43
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<.025
<.025
<.025
<.Q25
<.025
<.025
<.025
<.025
<.025
<.Q25
<.025
E.016
E.015
E.016
E.017
E.016
<.100
<.100
.303
<.100
.027
114
05
05
05
05
05
05
05
05
05
05
470
500
500
550
600
well head
well head
630
630
660
10.2
10.7
10.9
11.2
15.7
15.6
23.3
"
42.9
2.36
3.50
"
3.68
3.90
13.2
13.1
30.7
"
86.9
<.250
<.250
"
<.250
<.250
<.25Q
<.250
<.250
"
E.225
<.025
<.025
<.100
<.100
.239
.262
<.025
<.025
<.025
<.025
"
<.025
<.100
<.100
<.10Q
<.100
<.100
.262
.253
.246
.246
.240
<.100
<.100
^m
<.100
<.100
<.100
E.015
E.013
E.013
E.014
E.013
E.017
176
28.3
<.100
.259
195
63.1
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
Sampling
depth
(feet)
Arsenate,
filtered
(ug/L as As)
Arsenite,
filtered
(ug/L as As)
Dimethyl-
arsinate,
filtered
(ug/L as As)
Monomethyl-
arsonate,
filtered
(ug/L as As)
Barium,
filtered
(ug/L)
Beryllium,
filtered
(ug/L)
Boron,
filtered
(ug/L)
Cadmium,
filtered
(ug/L)
Chromium,
filtered
(ug/L)
Cobalt,
filtered
(ug/L)
Copper,
filtered
(ug/L)
Iron(ll),
filtered, field
(mg/L)
Iron, Iron,
filtered, field filtered
(mg/L) (ug/L)
02
02
02
02
02
02
02
02
02
02
02
420
<20
108
375
<37
.06
E45
E60
02
02
02
02
02
02
02
02
02
470
359
<3
934
<3
76
<3
<20
.01
.01
71
495
525
367
440
408
372
351
<3
<3
<3
<3
<3
1,030
1,040
1,200
1,860
2,270
<3
<3
<3
<3
<3
75
80
76
83
85
<3
<3
<3
<3
<3
05
05
05
05
05
05
05
05
05
05
05
05
well head
435
470
500
550
<20
<20
<20
<20
<20
285
296
344
321
289
782
788
912
838
68
64
68
69
<37
<37
<37
<37
.01
.04
.04
.03
644
68
<37
.09
<20
282
881
70
<37
.03
.12
.16
.19
.23
E35
E43
E63
E53
05
05
05
05
605
635
05
05
05
05
05
05
05
660 22 <
470 <10 <
500 <10 <
550 <10 <
600 <10 <
well head <10 <'
10 <20 <10 256
10 <10 <10 420
10 <10 E5.32 392
10 <10 <10 380
10 <10 <10 389
10 <10 <10 401
<13
<3
<3
<3
<3
<3
1,460
1,030
944
1,030
1,120
1,370
<13
<3
<3
<3
<3
<3
64
67
67
68
69
73
<10
<3
<3
<3
<3
<3
<37
<20
<20
<20
<20
<20
.10
.82
.17
.08
.02
.12
.93
.33
.15
.04
E62
79
68
68
73
85
well head
630
660
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well Sampling Lead, Manganese, Molybdenum, Nickel, Selenium, Silver, Strontium, Thallium, Titanium, Vanadium, Zinc, Uranium, Organic Deuterium Oxygen-18
depth filtered filtered filtered filtered filtered filtered filtered filtered filtered filtered filtered filtered carbon, /Protium /Oxygen-16
(feet) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) filtered ratio ratio
(mg/L) (per mil) (per mil)
02
02
02
02
02
02
02
02
02
02
02
420
<50
<50
<30
<100
<7
<20
<90
48
<33
<33
<57
<57
E.418
<.500
<.500
E.339
E.359
E.252
-37.0
-35.8
-6.32
-5.98
E.570
E.365
-39.7
-6.48
<20
<20
<20
<20
<20
<20
<20
E.338
<.500
__
<.500
<.500
<.500
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
06
06
06
06
06
06
06
06
06
06
06
07
07
07
07
07
07
07
07
13
13
13
13
13
13
13
13
13
13
15
15
15
15
15
15
15
15
15
15
USGS
station number
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351 357097242001
351414097293901
351414097293901
351414097293901
351414097293901
351414097293901
351414097293901
351414097293901
351414097293901
351550097283801
351550097283801
351550097283801
351550097283801
351550097283801
351550097283801
351550097283801
351550097283801
351550097283801
351550097283801
351648097285101
351648097285101
351648097285101
351648097285101
351648097285101
351648097285101
351648097285101
351648097285101
351648097285101
351648097285101
Station name
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-02W-27 BBB 2
09N-03W-23 CBC 1
09N-03W-23 CBC 1
09N-03W-23 CBC 1
09N-03W-23 CBC 1
09N-03W-23 CBC 1
09N-03W-23 CBC 1
09N-03W-23 CBC 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB 1
09N-03W-12CCB1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
09N-03W-1 1 AAC 1
Quality
assurance
sample
type
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Date
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Mar 25 2005
Nov 8 2004
Nov 8 2004
Nov 8 2004
Nov 8 2004
Nov 8 2004
Nov 8 2004
Nov 8 2004
Aug 24 2004
Aug 24 2004
Aug 24 2004
Aug 24 2004
Aug 23 2004
Aug 23 2004
Aug 23 2004
Aug 23 2004
Aug 23 2004
Aug 23 2004
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Jan 1 0 2005
Time
1100
1000
1000
1030
1030
1230
1330
1330
1400
1400
1200
1500
1500
1400
1300
1200
1000
1000
1100
1300
1300
1030
0900
1300
1300
1030
1130
0900
0900
1000
1000
0930
0900
1030
1030
1300
1230
1400
1400
Sampling
depth
(feet)
435
480
480
540
540
580
605
605
well head
well head
620
580
580
598
610
625
655
655
well head
490
515
535
560
595
well head
615
615
500
525
565
605
605
well head
625
645
645
Depth to Depth to top Elevation Flow rate
bottom of water of water- of land (gpm)
bearing zone bearing surface
(feet) zone (feet)
(feet)
1190
1190
1190
1190
1190
1190
1190
1162
1162
1162
1162
- -- 1162
1162
--
--
1155
1155
1155
1155
1155
1155
1155
1155
1155
Pumping Specific
period prior conductance,
to sampling field
(min) (uS/cm at
25 ฐC)
689
724
702
680
951
699
815
1,366
1,364
1,369
1,357
1,356
1 ,252
577
545
546
543
543
571
534
533
555
641
618
632
692
693
--
pH,
field,
standard
units
8.35
8.40
8.39
8.41
8.73
8.35
8.77
8.39
8.38
8.40
8.42
8.35
8.45
8.99
8.84
8.59
8.88
8.74
8.90
8.82
9.02
9.08
9.15
9.12
9.11
9.22
9.20
--
Temperature,
air
(ฐC)
12.4
8.3
8.9
14.8
13.6
14.8
13.2
22.0
21.8
21.2
19.5
19.5
19.5
--
--
15.1
13.7
12.4
15.4
18.7
17.2
18.7
--
Temperature,
water
(ฐC)
-
17.6
18.1
--
19.9
-
--
17.6
--
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
Sampling
depth
(feet)
Turbidity,
field
(NTU)
Barometric
pressure
(mm Hg)
Dissolved
oxygen,
field
(mg/L)
Dissolved
oxygen,
field
(%)
Calcium,
filtered
(mg/L)
Magnesium,
filtered
(mg/L)
Sodium,
filtered
(mg/L)
Sodium
adsorption
ratio
Potassium,
filtered
(mg/L)
Bicarbonate,
unfiltered
(mg/L)
Carbonate, Acid neutralizing
unfiltered capacity
(mg/L) (mg/L as
CaCO3)
14.0
382.1
07
07
07
07
07
07
07
07
580
580
598
610
625
655
655
well head
2.26
1.25
.67
1.16
.93
1.59
739.7
739.7
739.7
739.7
739.7
739.7
2.21
23.4
3.81
3.86
3.84
3.82
3.72
M
3.33
1.37
1.38
1.38
1.37
1.38
1.18
303
33.9
1.19
304
304
303
302
278
33.8
33.9
33.8
34.0
33.3
1.25
1.19
1.17
1.08
1.11
434.7
^m
439.6
444.6
437.1
441.5
426.4
7.6
1
6.9
8.0
7.4
7.7
8.5
369.3
372.0
378.1
371.0
375.0
363.9
13
13
13
13
13
13
13
13
13
13
490
490
515
535
560
595
well head
615
615
5.22
"
.77
3.92
2.15
.96
3.93
.96
731.0
1.61
.766
132
21.4
.648
290.9
731.0
731.0
731.7
731.7
731.7
731.7
5.95
68.2
2.13
1.98
2.06
.979
.959
.972
126
126
125
17.9
18.4
18.0
.722
.678
.671
285.8
272.8
291.9
10.3
12.5
3.1
252.7
257.7
247.7
253.7
251.7
244.7
244.7
15
15
15
15
15
15
15
15
15
15
500
500
525
565
605
605
well head
625
645
645
8.67
M
3.52
1.14
2.48
1.97
8.28
1.86
730.2
1.65
730.2
730.2
730.2
"
730.2
730.2
730.2
5.57
58.4
1.55
1.19
1.27
2.00
.949
.968
.995
M
.896
.547
.630
.712
.323
.320
124
129
148
145
147
162
163
18.8
M
20.4
28.2
26.3
"
22.7
36.7
36.7
.470
.470
.389
.431
gjg
.423
.342
.335
302.3
"
300.0
319.5
316.0
327.0
329.7
324.1
14.3
17.2
23.3
22.0
20.9
28.6
28.3
271.9
^m
275.0
301.2
296.2
303.3
318.4
313.4
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
Sampling
depth
(feet)
Sulfate,
unfiltered
(mg/L)
Chloride,
unfiltered
(mg/L)
Fluoride,
unfiltered
(mg/L)
Bromide,
unfiltered
(mg/L)
Iodine,
unfiltered
(mg/L)
Nitrite,
unfiltered
(mg/L as N)
Nitrite plus nitrate,
unfiltered
(mg/L as N)
Ammonia,
unfiltered
(mg/L as N)
Orthophosphate,
unfiltered
(mg/L as P)
Aluminum,
filtered
(ug/L)
Antimony,
filtered
(ug/L)
Arsenic,
filtered
(ug/L)
07
07
07
07
07
07
07
07
580
598
610
625
655
655
well head
278
"
282
284
282
292
294
223
22.2
21.9
22.6
22.7
21.9
23.2
20.3
2.15
2.17
2.19
2.22
2.13
2.16
1.99
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
E.012
<.025
<.025
<.025
<.025
E.010
<.025
<.100
E.033
<.l UU
<.100
<.100
<.100
<.10Q
<.100
b.Uo4
E.029
E.037
E.044
E.030
"
E.067
<.100
E.049
E.027
E.027
<.100
E.048
^m
E.063
.024
E.015
.023
.024
.024
.025
.027
E80
"
90
109
E61
E44
<57
M
<57
<57
<57
<57
<57
E36
M
E38
E39
E33
E40
13
13
13
13
13
13
13
13
13
13
490
515
535
560
560
595
well head
615
615
13.7
12.4
12.4
12.6
12.9
13.1
12.7
12.6
3.94
"
3.92
3.73
3.75
3.76
3.79
4.53
4.58
.21
.22
.23
.24
.23
.21
.28
<.250
<.250
<.250
<.250
<.25Q
<.250
<.250
<.250
<.025
<.025
<.025
<.025
<.Q25
<.025
<.025
<.025
<.100
.261
<.\ UU
<.100
<.100
<.10Q
<.100
<.100
<.100
.lib/
.277
.266
.272
.271
.267
.266
<.100
E.037
<.100
<.100
E.045
"
E.079
E.030
E.076
.030
.033
.032
.027
.029
"
.029
.030
.029
196
206
916
200
265
226
198
<57
<57
<57
<57
<57
<57
<57
E43
^H
E35
E37
E35
__
E38
E36
E37
15
15
15
15
15
15
15
15
15
15
500
500
525
565
605
605
well head
625
645
11.8
12.1
14.9
27.5
24.8
26.4
35.8
35.1
4.43
4.42
5.02
7.93
7.38
7.79
9.99
9.90
E.22
E.22
E.22
E.21
E.25
E.21
E.32
E.29
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<.025
<.025
<.025
<.Q25
<.025
<.025
<.025
<.Q25
<.025
<.100
.385
<.100
.028
<.100
<.100
<.100
^m
<.100
<.100
<.10Q
<.100
.404
.473
.457
M
.467
.530
.529
.532
<.100
<.100
E.034
"
E.074
E.048
<.10Q
<.100
.030
.033
.033
.032
.037
.037
E44
E42
E75
E70
E33
E64
<57
<57
<57
<57
M
<57
<57
<57
E37
E51
E50
"
E49
E60
E60
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
Sampling
depth
(feet)
Arsenate,
filtered
(ug/L as As)
Arsenite,
filtered
(ug/L as As)
Dimethyl-
arsinate,
filtered
(ug/L as As)
Monomethyl-
arsonate,
filtered
(ug/L as As)
Barium,
filtered
(ug/L)
Beryllium,
filtered
(ug/L)
Boron,
filtered
(ug/L)
Cadmium,
filtered
(ug/L)
Chromium,
filtered
(ug/L)
Cobalt,
filtered
(ug/L)
Copper, Iron(ll), Iron, Iron,
filtered filtered, field filtered, field filtered
(ug/L) (mg/L) (mg/L) (ug/L)
06
06
06
06
06
06
06
06
06
06
06
435
480
10
<20
<20
579
587
1,580
1,580
19
16
<37
<37
.13
.19
.13
E57
E57
540
well head
well head
620
10
21
<20
659
1,640
17
<37
.06
<37
<37
.07
16
E73
E67
E93
E41
<37
<37
<37
<37
<37
<37
<37
.07
.07
.02
.06
.03
.01
.15
.18
.07
.21
E107
^
E110
E109
E102
15
15
15
15
15
15
15
15
15
15
500
27
<20
238
1,170
19
<37
<37
<37
<37
<37
<37
<37
.07
.02
.02
.02
.10
.24
645
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well Sampling Lead, Manganese, Molybdenum, Nickel, Selenium, Silver,
depth filtered filtered filtered filtered filtered filtered
(feet) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L)
Strontium, Thallium, Titanium, Vanadium, Zinc, Uranium, Organic Deuterium Oxygen-18
filtered filtered filtered filtered filtered filtered carbon, /Protium /Oxygen-16
(ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) filtered ratio ratio
(mg/L) (per mil) (per mil)
07
07
07
07
07
07
07
07
580
<50
598
610
625
655
655
well head
<50
<50
<50
<50
"
<50
E3
<10
E3
52
<100
<100
<100
<100
<100
<100
<7
<7
<7
<7
<7
<7
97
98
100
97
96
"
84
<90
IB
<90
<90
<90
<90
i
<90
76
78
104
58
45
93
E19
I
E21
E21
E18
E13
"
83
<57
<57
<57
<57
<57
<57
29
27
21
42
44
16
.655
E.302
.558
<.500
1.38
1.51
<.500
-41.4
-6.72
-39.2
-6.51
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well USGS Station name Quality Date Time Sampling Depth to Depth to top Elevation
station number assurance depth bottom of water of water- of land
sample (feet) bearing zone bearing surface
type (feet) zone (feet)
(feet)
Flow rate Pumping Specific
(gpm) period prior conductance,
to sampling field
(min) (uS/cm at
25 ฐC)
pH, Temperature, Temperature,
field, air water
standard (ฐC) (ซC)
units
18
18
18
18
18
18
18
18
18
351726097290901
351726097290901
351726097290901
351726097290901
351726097290901
351726097290901
351726097290901
351726097290901
351726097290901
09N-03W-02 BAA 1
09N-03W-02 BAA 1
09N-03W-02 BAA 1
09N-03W-02 BAA 1
09N-03W-02 BAA 1
09N-03W-02 BAA 1
09N-03W-02 BAA 1
09N-03W-02 BAA 1
09N-03W-02 BAA 1
Duplicate
Duplicate
Duplicate
Jan 20 2005
Jan 20 2005
Jan 20 2005
Jan 20 2005
Jan 20 2005
Jan 20 2005
Jan 20 2005
Jan 20 2005
Jan 20 2005
1030
1030
1000
1000
1100
1100
1330
1230
1300
1180
1180
1180
1180
1180
1180
1180
1180
1180
567
8.96
14.6
570
8.96
11.9
573
19.7
576
573
582
8.89
8.96
8.92
19.8
19.9
19.8
17.5
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
09N-02W
09N-02W
09N-02W
09N-02W
09N-02W
09N-02W
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
Duplicate
Duplicate
Duplicate
Duplicate
Replicate
Duplicate
Duplicate
Duplicate
Sep182003
Sep 182003
Sep172003
Sep 17 2003
Sep 192003
Sep 19 2003
Sep 182003
Sep 182003
Sep 18 2003
Sep 18 2003
Sep 172003
Sep 17 2003
Sep 172003
Sep 16 2003
Sep 162003
1213
1213
1213
1213
1213
1213
1213
1213
1213
1213
1213
1213
1213
1213
1213
5.5
3.3
5.4
6.7
6.7
3.5
3.9
4.5
41
43
78
45
759
9.01
18.72
973
8.85
20.11
956
19.46
940
920
8.90
8.87
18.64
18.6
73
45
936
924
8.90
8.95
19.51
19.77
23
23
23
23
23
23
23
23
23
23
23
23
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
351401097252301
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W
09N-02W
09N-02W
09N-02W
09N-02W
09N-02W
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
21 CCC 1
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
May 11 2004
May 11 2004
May 10 2004
May 6 2004
May 6 2004
May 5 2004
May 5 2004
May 4 2004
May 4 2004
May 3 2004
May 11 2004
May 11 2004
0900
0900
1300
0900
0900
1100
1100
1200
1200
1100
1300
1300
881
8.97
816
801
9.04
829
8.96
902
8.95
912
8.87
8.95
19.5
31
31
31
31
31
31
31
31
31
31
31
351542097262801
351542097262801
351542097262801
351542097262801
351542097262801
351542097262801
351542097262801
351542097262801
351542097262801
351542097262801
351542097262801
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
17 BBS 1
Duplicate
Duplicate
Duplicate
Duplicate
Apr 5 2005
Apr 5 2005
Apr 5 2005
Apr 4 2005
Apr 5 2005
Apr 5 2005
Apr 5 2005
Apr 5 2005
Apr 4 2005
Apr 4 2005
Apr 4 2005
0900
0900
1430
1430
1000
1000
1300
1200
1300
1030
1030
480
480
525
525
540
540
well head
560
620
645
645
1170
21.8
1170
651
8.99
23.5
1170
1170
1170
1170
1170
1170
1170
655
8.93
22.3
652
657
668
655
8.84
8.95
8.99
25.3
25.3
22.4
21.5
17.7
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
18
18
18
18
18
18
18
18
18
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23
23
23
23
23
23
23
23
23
23
23
23
31
31
31
31
31
31
31
31
31
31
31
Sampling
depth
(feet)
495
495
535
585
well head
615
655
420
445
485
510
550
560
well head
well head
480
525
540
well head
560
620
645
645
Turbidity,
field
(NTU)
.40
.81
.46
.29
.80
1.58
1.08
1.37
3.36
4.91
4.72
17.0
^H
19.8
6.53
2.17
1.88
1.37
.76
.56
2.57
.68
.76
1.14
1.09
.51
2.88
1.28
1.89
Barometric Dissolved Dissolved
pressure oxygen, oxygen,
(mm Hg) field field
(mg/L) (%)
730.3
730.3
730.3
730.3 6.65 69.7
730.3
730.3
732.0 3.63 40.6
732.3 1.68 19.4
732.3 3.79 43.1
5.70
5.7
732.3 1.80 20.7
730.3 2.12 24.2
736.4 2.60 29.6
730.2
732.7
731.4
731.0
731.0
731.0
730.2 2.88 32.9
722.8
727.4
722.8
722.8 5.72 61.8
722.8
727.4
727.4
Calcium,
filtered
(mg/L)
1.40
1.46
1.46
1.49
1.39
1.44
1.23
1.43
1.29
1.31
1.29
1.34
1.38
1.34
1.29
1.29
1.26
1.28
1.28
1.28
1.29
1.76
1.75
1.97
1.85
1.94
2.29
2.17
Magnesium,
filtered
(mg/L)
.544
.542
.545
.560
.529
.548
.672
.588
.537
.537
.529
.561
.580
.556
.588
.669
.651
.634
.598
.601
.605
.663
.659
.729
.685
.731
.733
.687
Sodium,
filtered
(mg/L)
134
134
136
134
135
136
180
232
223
224
222
224
225
221
199
187
179
202
208
213
210
147
145
147
149
149
151
150
Sodium
adsorption
ratio
24.3
24.1
24.4
23.8
24.7
24.5
32.4
41.2
41.6
41.6
41.6
41.0
40.5
40.5
36.5
33.3
32.3
36.5
38.1
38.9
38.2
24.0
23.7
22.7
23.8
23.1
22.2
22.7
Potassium,
filtered
(mg/L)
.385
.568
.586
.597
.449
.482
.489
.561
.552
.559
.555
.545
.551
.514
1.45
^^H
1.35
1.36
1.26
1.50
1.28
1.45
.479
.497
.488
.497
.519
.518
.534
Bicarbonate,
unfiltered
(mg/L)
298.5
304.7
303.8
299.8
307.7
312.6
342.9
401.5
E342.9
364.9
365
396.6
367.3
E368.8
390.3
^^^m
363.0
387.3
387.7
301.9
357.0
413.5
309.4
312.6
303.1
306.9
304.0
309.9
309.9
Carbonate, Acid neutralizing
unfiltered capacity
(mg/L) (mg/L as
CaCO3)
14.9
14.9
13.6
14.3
14.1
13.5
19.2
12.0
E33.6
21.6
22
10.8
27.6
E64.1
22.5
^^m
23.2
20.9
21.9
19.7
3.3
21.3
17.4
^^^^H
16.8
18.0
14.3
15.8
15.2
15.2
269.9
275.0
271.9
269.9
276.0
279.0
313.3
349.3
337.3
335.3
335
343.3
347.3
409.4
"
357.8
^^H
336.8
352.8
354.8
280.7
298.3
374.8
283.0
-M
284.7
279.0
276.0
276.0
279.7
279.7
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
18
18
18
18
18
18
18
18
18
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23
23
23
23
23
23
23
23
23
23
23
23
31
31
31
31
31
31
31
31
31
31
31
Sampling
depth
(feet)
495
535
585
well head
615
655
420
445
485
510
550
560
well head
well head
480
525
540
well head
560
620
645
645
Sulfate,
unfiltered
(mg/L)
19.1
193
19.4
19.9
19.9
20.9
21.7
37.5
82.6
83.4
76.6
75.7
76.0
76.5
76.1
75.2
75.8
51.8
48.3
57.9
58.8
61.4
62.4
68.6
68.4
39.9
39.6
38.8
39.2
38.5
38.5
38.6
Chloride,
unfiltered
(mg/L)
10.6
104
10.5
10.7
10.7
10.9
11.0
8.35
13.9
13.9
13.2
13.1
13.1
13.1
13.0
13.4
13.3
10.2
9.59
11.2
11.3
11.8
11.9
12.9
13.0
10.5
10.6
11.4
10.7
10.9
13.7
12.2
Fluoride,
unfiltered
(mg/L)
E.21
E.21
E.19
E.19
E.21
E.19
E.20
.385
.658
.648
.645
.646
.636
.633
.633
.493
.716
.699
E.47
E.43
.52
.55
.58
.54
.57
.57
E.29
E.26
.29
E.28
E.32
E.28
E.29
E.33
Bromide,
unfiltered
(mg/L)
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<.250
<.250
<.250
<.250
E.191
E.110
<.250
E.163
E.21 5
E.086
E.084
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
<1.00
Iodine,
unfiltered
(mg/L)
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
Nitrite, Nitrite plus nitrate
unfiltered unfiltered
(mg/L as N) (mg/L as N)
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.10Q
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
.682
--M
.678
.678
.680
.686
.681
.150
.119
.119
.121
.125
.123
.127
.132
.129
.123
.132
.130
.126
.123
.125
.120
.113
.504
.507
.506
.504
.506
.503
.543
.515
, Ammonia,
unfiltered
(mg/L as N)
.135
.135
<.100
<.100
.247
E.072
E.05
<.100
^^^m
E.03
E.004
E.07
E.060
E.06
E.05
E.08
<.100
.204
E.062
E.056
E.030
E.039
E.067
.175
<.100
<.100
<.100
<.100
<.100
<.100
Orthophosphate,
unfiltered
(mg/L as P)
E.019
E.016
E.016
E.016
E.017
E.017
.057
.051
.051
.053
.057
.056
.054
.064
.054
.052
.049
.049
.052
.061
.060
.061
.058
.055
E.015
.031
.031
.031
.030
.029
.030
Aluminum,
filtered
(ug/L)
93
740
"
805
744
E53
125
E38
<87
<87
<87
<87
E27
E34
<87
114
140
165
E30
<87
<87
139
153
143
128
148
174
150
163
Antimony,
filtered
(ug/L)
<57
<57
^^H
<57
<57
<57
<57
<57
<57
^^H
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
<57
Arsenic,
filtered
(ug/L)
<110
<110
^^^
<110
<110
<110
<110
E99
174
^^^
173
179
175
172
165
161
120
E100
E96
122
122
127
143
44.3
43.9
41.2
41.8
40.4
40.2
41.4
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well Sampling Arsenate, Arsenite,
depth filtered filtered
(feet) (ug/L as As) (ug/L as As)
Dimethyl-
arsinate,
filtered
(ug/L as As)
Monomethyl-
arsonate,
filtered
(ug/L as As)
Barium, Beryllium, Boron, Cadmium, Chromium, Cobalt, Copper, Iron(ll), Iron, Iron,
filtered filtered filtered filtered filtered filtered filtered filtered, field filtered, field filtered
(ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (mg/L) (mg/L) (ug/L)
18
18
18
18
18
18
18
18
18
16
<37
15
<37
585
585
well head
615
655
17
18
<16
16
<20
<20
<20
<20
356
1,480
16
<37
.05
335
136
154
1,460
905
1,110
16
16
17
<37
<37
<37
.02
.06
.06
.08
.02
.09
.11
E93
E87
<117
E56
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
43
1,600
20
<37
E99
116
107
27
31
2,720
2,630
13
14
<37
<37
E55
E76
E70
31
31
31
31
31
31
31
31
31
31
31
480
41
<20
259
1,520
26
<37
.01
E69
525
44
<20
233
1,660
26
<37
.08
.28
E69
540
35
<20
223
1,580
31
<37
.01
E60
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well Sampling Lead, Manganese, Molybdenum,
depth filtered filtered filtered
(feet) (ug/L) (ug/L) (ug/L)
Nickel, Selenium, Silver, Strontium, Thallium,
filtered filtered filtered filtered filtered
(ug/L) (ug/L) (ug/L) (ug/L) (ug/L)
Titanium, Vanadium, Zinc, Uranium,
filtered filtered filtered filtered
(ug/L) (ug/L) (ug/L) (ug/L)
Organic Deuterium
carbon, /Protium
filtered ratio
(mg/L) (per mil)
Oxygen-18
/Oxygen-16
ratio
(per mil)
18
18
18
18
18
18
18
18
18
495
495
535
535
585
585
well head
615
655
<50
<50
<50
<50
<50
<50
<90
<90
83
-36.4
127
<90
145
60
<57
134
50
75
59
58
62
<57
<57
<57
1.29 -
1.38
E.260 -36.2
E.324
.69 -34.8
-6.02
-6.06
-6.07
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
23p
<50
<50
<50
<50
<50
28
28
29
<90
<90
<90
<27
<27
<27
546
539
533
E18
<57
E27
85
81
142
E3
<30
<30
E68
E75
<7
<7
29
28
<90
<90
<27
<27
537
523
E23
E49
82
76
-37.9
-38.8
-6.27
-6.23
23
23
23
23
23
23
23
23
23
23
23
23
420
420
445
485
485
510
510
550
<50
<50
<50
<50
<50
560
well head
well head
<50
<50
4.47
-39.3
<30
E53
27
<90
<27
437
<57
67
3.15
<30
E46
<7
27
<90
<27
478
E20
67
<30
<30
<47
E65
<7
<7
27
29
<90
<90
<27
493
497
<57
<57
67
85
6.51
2.13
.923
-38.4
-37.8
-6.38
-6.26
-6.26
31
31
31
31
31
31
31
31
31
31
31
480
480
525
525
540
540
well head
560
620
645
645
<50
<50
<50
<50
<50
<50
<50
71
-38.2
<30
E33
45
<90
63
162
<57
3.76
<30
<30
<30
<30
E34
<100
E40
E38
<7
<7
35
<7
42
44
45
42
<90
<90
<90
<90
72
83
70
75
160
163
150
154
<57
<57
<57
<57
-38.6
E.258
3.27
.882
.557 -38.1
.565
-6.43
-6.48
-6.47
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well USGS Station name Quality Date Time Sampling Depth to Depth to top Elevation
station number assurance depth bottom of water of water- of land
sample (feet) bearing zone bearing surface
type (feet) zone (feet)
(feet)
Flow rate
(gpm)
Pumping
period prior
to sampling
(min)
Specific
conductance,
field
(uS/cm at
25 ฐC)
pH, Temperature, Temperature,
field, air water
standard (ฐC) (ซC)
units
33
33
33
33
33
33
33
33
33
33
33
33
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
351541097245301
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
16 ABB 1
16 ABB 1
16 ABB 1
16ABB1
16 ABB 1
16ABB1
16ABB1
16 ABB 1
16ABB1
16 ABB 1
16 ABB 1
16ABB1
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Replicate
Mar 15 2006
Mar 152006
Apr 10 2006
Apr 10 2006
Apr 102006
Apr 10 2006
Apr 10 2006
Apr 102006
Apr 10 2006
Apr 102006
Apr 102006
Apr 10 2006
1300
1300
1400
1400
1130
1130
1230
1230
1300
1300
1301
1500
well head
well head
440
440
500
500
550
550
595
595
595
well head
1170
1170
1170
7.98
17.9
19.5
1170
434
7.69
19.6
1170
428
8.03
19.2
1170
1170
1170
1170
432
19.3
19.48
18.1
36
36
36
36
36
36
36
36
36
36
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
10 BBS 1
10 BBS 1
10 BBS 1
10 BBS 1
10 BBS 1
10BBB1
10 BBS 1
10 BBS 1
10BBB1
10 BBS 1
Duplicate
Duplicate
Duplicate
Oct 28 2004
Pel 28 2004
Oct 28 2004
Oct 28 2004
Oct 29 2004
Pel 29 2004
Oct 29 2004
1500
1400
1400
1300
1400
1100
1100
Oct 29 2004
Pel 29 2004
Oct 29 2004
0930
1500
1500
415
480
480
520
595
645
645
680
well head
well head
1080
1080
1080
1080
1080
1080
455
454
8.48
7.70
26.7
26.6
442
449
449
7.54
7.68
7.79
26.6
29.6
27.5
1080
1080
1080
440
472
7.70
7.74
25.4
30.0
17.7
36
36
36
36
36
36
36
36
36
36
36
36
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
09N-02W-
10 BBS 1
10BBB1
10 BBS 1
10 BBS 1
10BBB1
10 BBS 1
10 BBS 1
10BBB1
10 BBS 1
10BBB1
10BBB1
10 BBS 1
Blank
Duplicate
Duplicate
Replicate
Duplicate
Duplicate
Jun 7 2005
Jun 7 2005
Jun 7 2005
Jun 7 2005
Jun 8 2005
Jun 7 2005
Jun 7 2005
Jun 7 2005
Jun 7 2005
Jun 7 2005
Jun 7 2005
Jun 8 2005
0900
0901
1230
1230
0900
1200
1000
1000
1300
1300
1301
1000
480
480
520
595
645
64!
680
680
680
well head
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
448
7.75
447
469
469
7.75
7.82
7.88
520
539
8.18
8.24
18.0
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well
33
33
33
33
33
33
33
33
33
33
33
33
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
Sampling
depth
(feet)
well head
well head
440
440
500
500
550
550
595
595
595
well head
415
480
480
520
595
645
645
680
well head
well head
480
480
520
595
645
645
680
680
680
well head
Turbidity,
field
(NTU)
.62
-
1.31
1.47
1.08
-
.72
-
1.19
.46
1.01
.11
-
.72
.85
.86
.88
.67
-
-
-
1.28
.31
1.00
1.13
-
.80
.31
Barometric Dissolved Dissolved
pressure oxygen, oxygen,
(mm Hg) field field
(mg/L) (%)
734.2 6.37 67.0
..
734.1
734.1
734.1
..
734.1
..
734.1
734.1 6.00 63.6
738.1
738.1
..
738.1
732.3
732.3
732.3
732.3 6.10 64.2
..
..
..
734.5
733.6
735.0
733.4
..
735.2
733.2 6.51 82.5
Calcium,
filtered
(mg/L)
22.8
22.8
28.2
22.6
21.3
21.3
21.2
-
21.3
22.3
26.1
26.1
-
26.0
25.9
25.8
26.1
21.3
-
E45
-
25.8
25.8
18.8
20.8
20.9
15.1
13.8
Magnesium,
filtered
(mg/L)
19.7
20.0
24.2
19.6
18.5
18.4
18.3
-
18.5
19.4
21.3
21.3
-
21.2
21.1
21.0
21.2
17.3
-
<.300
-
20.9
20.9
14.9
16.4
16.6
11.9
10.9
Sodium,
filtered
(mg/L)
36.1
36.1
27.8
37.6
40.9
41.0
40.4
-
40.6
38.2
34.4
34.6
-
34.5
35.6
35.5
36.0
55.1
-
.754
-
35.0
34.9
54.2
55.4
54.6
82.6
93.1
Sodium
adsorption
ratio
1.34
1.33
.93
1.40
1.56
1.57
1.55
-
1.55
1.43
1.21
1.22
-
1.22
1.26
1.26
1.27
2.15
-
-
-
1.24
1.24
2.27
2.21
2.16
3.86
4.55
Potassium,
filtered
(mg/L)
2.00
2.06
2.50
2.15
2.07
2.07
2.06
-
2.14
2.16
2.42
2.39
-
2.38
2.40
2.39
2.45
2.13
-
E.105
-
2.48
2.44
2.09
2.13
2.08
1.79
1.64
Bicarbonate,
unfiltered
(mg/L)
219.0
-
231.3
220.2
220.0
-
229.8
-
219.1
223.6
174.7
264.1
-
265.0
261.2
263.2
302.7
364.8
-
-
-
267.9
265.8
277.1
281.4
-
302.9
314.3
Carbonate,
unfiltered
(mg/L)
<.1
-
.2
.2
.3
-
.3
-
.1
.4
2.1
.6
-
.9
.5
.6
.8
1.2
-
-
-
1.0
.8
1.3
1.6
-
3.1
4.2
Acid neutralizing
capacity
(mg/L as
CaCO3)
179.9
-
190.0
180.9
180.9
-
189.0
-
179.9
184.0
146.8
217.5
-
218.9
215.0
216.9
249.6
301.2
-
-
-
221.4
219.4
229.5
233.5
-
253.7
264.9
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well Sampling Sulfate, Chloride, Fluoride, Bromide, Iodine, Nitrite, Nitrite plus nitrate, Ammonia, Orthophosphate, Aluminum, Antimony, Arsenic,
depth unfiltered unfiltered unfiltered unfiltered unfiltered unfiltered unfiltered unfiltered unfiltered filtered filtered filtered
(feet) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L as N) (mg/L as N) (mg/L as N) (mg/L as P) (ug/L) (ug/L) (ug/L)
.423
36
36
36
36
36
36
36
36
36
36
well head
<.100
.484
<.100
<1.00
5.09
5.18
4.74
5.66
5.39
8.32
8.20
11.1
<.100
E.132
E.154
.217
.238
.225
.384
.400
.535
<1.00
<1.00
^m
<1.00
<1.00
<1.00
<.025
<.025
^m
<.025
<.025
<.025
<1.00
<1.00
<1.00
<1.00
<.025
<.025
<.025
<.025
<.100
<.100
<.100
<.100
<.100
<.100
E.049
<.100
.460
<.100
.034
212
<57
16.5
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well Sampling Arsenate, Arsenite, Dimethyl- Monomethyl-
depth filtered filtered arsinate, arsonate,
(feet) (ug/LasAs) (ug/L as As) filtered filtered
(ug/L as As) (ug/L as As)
Barium, Beryllium,
filtered filtered
(ug/L) (ug/L)
Boron, Cadmium, Chromium, Cobalt, Copper, Iron(ll), Iron, Iron,
filtered filtered filtered filtered filtered filtered, field filtered, field filtered
(ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (mg/L) (mg/L) (ug/L)
1,760
<37
.01
.08
90
-------
Appendix 4. Chemical analyses of ground-water samples and quality-assurance samples collected to assess potential for arsenic remediation by well
modification in 11 selected public-supply wells, Norman, Oklahoma, 2003-2006. (continued)
Well Sampling Lead, Manganese, Molybdenum, Nickel, Selenium, Silver, Strontium, Thallium,
depth filtered filtered filtered filtered filtered filtered filtered filtered
(feet) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L)
Titanium, Vanadium, Zinc, Uranium,
filtered filtered filtered filtered
(ug/L) (ug/L) (ug/L) (ug/L)
Organic Deuterium
carbon, /Protium
filtered ratio
(mg/L) (per mil)
Oxygen-18
/Oxygen-16
ratio
(per mil)
33
33
33
33
33
33
33
33
33
33
33
33
well head
well head
440
440
500
500
550
550
595
595
595
well head
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
3
E1
<3
E2
<3
E3
E3
<3
<3
E9
E9
E1
E1
<.500
<.500
-38.5
-6.35
36
36
36
36
36
36
36
36
36
36
36
36
480
<50
<50
520
595
645
<50
<50
<50
680
680
680
well head
<50
<50
E2
E1
E3
E1
<100
E7
<7
<7
662
<90
E11
72
115
<33
E6
<57
<57
2.37
2.42
.720
E3
4
4
E8
E15
E15
E32
E40
<7
<7
<7
<7
<7
659
484
531
532
393
357
1.67
1.09
.968
<.500
E.483
<90
122
239
<57
1.18
-------
Appendix 5A Natural gamma-ray log, open-interval (screen) log, flow contribution, and water quality with depth in Norman Well 02, March 2005
[|o,g/L, micrograms per liter; NQ, not quantifiable; %, percent; Q, estimated well yield in gallons per minute (gpm); BQL, below
practical quantitation limit; EPA MCL, Environmental Protection Agency maximum contaminant level for arsenic].
EXPLANATION
350
400
LJJ 450
O
LL
o;
ง 500
o
DEPTH, IN FEET BE
งOl
Ol
650
700
750
0
SP
P
F^P
67% P
33% I
creened interval showing ^ Pumping
ercent flow contribution water level spEc|p|c SQD|UM BICARBONATE VANADIUM BORON
ercent of well yield ฐ Pump intake CONDUCTANCE IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
oming from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
nd below the pump Q=376 + 24 gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION
~ D
a(
- Si
Prol
well
Bep
uife
sten
C
{
jablf
bolt
^^
T
T
<
1 =:
_y
;
c
f
<
V
i
^
_i.
,iป
t
^
r=
>
^
1
)
l
\
-
-
-
"
-
-
-
-
-
-
-
-
-
14%
T
7.4 %
6.;
1ฃ
IS
c
i
3ฃ
0
350 -
400
%
450 -
% 500
Q
5
550 f
600
18%
20 40 60 80 100
ONTANEOUS POTENTIAL,
ERCENT OF FULL SCALE
650 -
700
750 -
0
20 40 60 80 1C
JC.
a
Jir
g
4C
5"
.
-
-
i
20 40 60 80 1C
PERCENTAGE OF
TOTAL FLOW
)0 4
350
400
450
500
550
600
650
700
750
)0 7
00 800 1,2
I ;
Specif c conductance
*PH i
Note: Well-head
concentrations are
represented by
hollow markers at
the depth of the1
pump intake.
-
ii ป
n |
\ \
\\ \
%\ \
i ;
.0 8.0 9
pH, IN
STANDARD UNITS
00 C
350
400
450
500
550
600
650
700
750
0 C
50
100 1
1
Magnesium
* Calcium
Sodium
Potass um
-
o
III"
- 3
"
o m <
<
Magnesium
4TTg
I
V
!
i
5 10 1
CONSTITUENT
CONCENTRATION
IN MILLIGRAMS
50 0
350
400
450
500
550
600
650
700
750
5 0
200
400 6
1 1
Carbonate
* Chloride
Sulfate
A Bicarbonate
Carbonate
-/ Chloride
/ /
7 ฅ *
P> l"w ^
CD"
M '
R
i
i -
i
i
i
20 40 6
CONSTITUENT
CONCENTRATION
IN MILLIGRAMS
DO C
350
400
450
500 '
550
600
|
650
700
750
0 BC
50 100 150 2
I
4 Arsenic
Selenium
A Vanadium
Chromium
p
1
i ii
a n
> i- \
\;\ \^% \
\ o
g 1 \ I
52. \ F
1 ง \ I
1 1
)L 25 50 75 1
CONSTITUENT
CONCENTRATIOh
IN MICROGRAMS
00
350
400
450
500
550
600
650
700
750
00
J,
j 1,000 2,000 3,000
I I
Strontium
4 Barium
Boron
-
, m
- 4 1
/ \
O CD \^
E i- \
-33 \ -
-
I I
j 500 1,000 1,500
CONSTITUENT
CONCENTRATION,
IN MICROGRAMS
PER LITER PER LITER PER LITER PER LITER
-------
Appendix 5B. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 05, November
2005 [ng/L, micrograms per liter; API, American Petroleum Institute; NQ, not quantifiable; %, percent; Q, estimated well yield in
gallons per minute (gpm); EPA MCL, Environmental Protection Agency maximum contaminant level for arsenic].
EXPLANATION
Perforated interval showing ^ Pumping
L^ percent flow contribution water level SREC|RC SOD|UM BICARBONATE VANADIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
33% coming from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=249ฑ16gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION 0 20406080100 400 700 1,0001,300 0 100 200 300 0 125 250375500 0 150300450600 0 2,0004,0006,000
onn onn onn onn onn onn onn
oUU
350
uj 400
CJ
LL
o;
z)
co
/i
i 450
o
_i
UJ
[f 500
UJ
UJ
LL
^
I
t 550
UJ
Q
600
650
700
s
"^:
<^
f
X
c^
^
<
^
<^'
-r-^
V
^
c
^
a
ฃ
J-
_g
JS
rp*
r=-
1
=^
_
C
^^
-^
-^
^^
-=
-
D
fer -
em -
-
_
^
:
-
-
"
-
-
~
-
-
-
i-
-
-
_
_
-
.
-
-
-
6.3 %
W
3.8"%
8.<
8.'
12
7.1
15
lj
42
P
OUU
350 1
400
450
500
550
600
650
vnn
_
-
N
CO
0
3)
5
ฃ2
Q
5!
ซ
ฐ;
!ฐ;
_
-
o
ouu
350
400
450
500
550
600
650
vnn
1 '
Specific conductance
* PH
Note: Well-hea
d
concentrations are
represented by
hollow markers
a
the depth of the
pump intake.
*
\,
tt *
g.
o
o
Q.
c
111 <
8
-
k_
^---.
i i
_
>
1
1
T
1
i
M"
" 4
i,
ii
OUU
350
400
450
500
550
600
650
vnn
1
Magnesium
^ Calcium
Sodium
Potassium
_
Potassium
/ Magnesium
/ / Calcium
T Tft
ii",,
I IK>
u
L
o
1 \3
m ^
/
i
OUU
350
400
450
500
550
600
650
vnn
1 '
Carbonate
* Chloride
Sulfate
A Bicarbonate
_
> A
II j k
CD
w S"
Q? O
CD"
II 1 ^
II 1
H i
\
ii L
T^\
)i * \^iป
Carbonate Chloride
OUU
350
400
450
500
550
600
650
vnn
,i i i
* Arsenic
Selenium
A Vanadium
Chromium
> m
3 J
< P
1
t '
i i
it
^
CD
3
41
I
\
-
o
3
-
-
nfr^-A^M^
' s^1^ /^^^
./ /
;Arsenic /
; Vanadium
: i i i
OUU
350
400
450
500
550
600
650
vnn
A Strontium
* Barium
1 Boron
_
"
Tt f
1
0 1
1 I
II u <
- IIA o
1 3
,U
" /~"\J
^^
/ UU / uu / \j\j i \j\j i \j\j i \j\j i \j\j
18 30 42 54 66 78 0 2Q 40 60 80 100 6.0 7.0 8.0 9.0 0 10 20 30 0 25 50 75 100 0 30 60 90 120 0 200 400 600
IN API UNITS ' PERCENTAGE OF PH, IN
CONSTITUENT CONSTITUENT CONSTITUENT CONSTITUENT
TOTALFLQW STANDARD UNITS CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
PER LITER PER LITER PER LITER PER LITER
-------
Appendix 5C. Natural gamma ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 06, March
2005 [ng/L, micrograms per liter; API, American Petroleum Institute; NQ, not quantifiable; %, percent; Q, estimated well yield in
gallons per minute (gpm); EPA MCL, Environmental Protection Agency maximum contaminant level for arsenic].
EXPLANATION
Perforated interval showing ^ Pumping
L^ percent flow contribution water level spEc|Rc SOD|UM BICARBONATE VANADIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION CONCENTRATION,
33% comin9 from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=259ฑ17gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION 0 20 40 60 80100 600 800 1,000 0 75 150 225 0 120 240 360480 0 75 150 225 300 0 2000 4,0006,000
"rii-i li-irt Irti-i t~,nn t~,nn t~,nn t~,nn
300
350
LJJ 400
O
2
a:
i 450
<
i
g
O
1
UJ
H 500
UJ
LJJ
Z
I
t 550
LJJ
O
600
700
! ^
_
- g~
- ซ
_
c
<:
- ^
=t
^^
^
j=
~^
^s
^^^
JjF
*c
J
^-~^
=c:
~~
==-
%-~
rr=
^r=>
^==-
^
1 '
-=i
^ ~
P="
3
V
_s~
'
^^
^5_
^
Dee
jgu
syst
~^-
s
^^r
^=
^
^
_^^
____
^
D -
fer -
em -
12%
V
26
25
1
Q
37.%
1
1
ouu
350
400
450
500
550
600
650
700
-
-
s
^
a
c
cc
f
:
>3
ฐX
ฐx
-
-
ouu
350
400
450
500
550
600
650
700
1
Specif c conductance
* pH
Note: Well-head
concentrations are
- represented by
hollow markers at
the depth of the
pump ntake.
i
*
O \
-3o>\ \o
O-"O 1 ^C
C ฎ \
g.o.\
8 1 .
!
. J"
l\
^^^
H3*cir*i=:^^
^=r--*
i
ouu
350
400
450
500
550
600
650
700
Magnesium
* Calcium
Sodium
-
II <
II <
s
1
1
1 1 <
-//
A
O
l
1
-
\
V\> Ajf
^* ^A
ouu
350
400
450
500
550
600
650
700
Carbonate
ป Chloride
Sulfate
A Bicarbonate
, Carbonate
/
/ Chloride
/ /
TTf t
g
3
oT
lซ>ll A
-
CO
QJ
r11 It
CD"
1
\V\ i
f^g^ A
1 1
ouu
350
400
450
500
550
600
650
700
4 Arsenic
Selenium
A Vanadium
Chromium
3 5
i'o
3^
^ Arsenic
- ; /
/ Chromium
/ /
7 /
ป
01
_
CD
1'
3
1 L O
-
o
o
3
A o ||
-u >
1\ 3^
1** "^
0 20 40 60 80 o 20 40 60 80 100 8.0 8.5 9.0 0 5 10 15 0 20 40 60 80 0 25 50 75 100 0 800 1,600 2,400
NA}MJAPMiKnT^A' PERCENTAGE OF pH, IN CONSTITUENT CONSTITUENT CONSTITUENT CONSTITUENT
INAMUNII& TOTALFLOW STANDARD UNITS CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
PER LITER PER LITER PER LITER PER LITER
-------
Appendix 5D. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 07, November
2004 [|o,g/L, micrograms per liter; NQ, not quantifiable; %, percent; Q, estimated well yield in gallons per minute (gpm); BQL, below
practical quantitation limit; * indicates that flow contribution was determined by subtracting flow above the pump, calculated using an
effective area of 0.21 square foot, from the maximum estimate of well yield; EPAMCL, Environmental Protection Agency maximum
contaminant level for arsenic].
EXPLANATION
JTI Perforated interval showing ^ Pumping
oercent flow contribution "" water level bULI-AlhANLJ
I percent TIOW coninouiion SPECIFIC SODIUM BICARBONATE VANADIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION CONCENTRATION CONCENTRATION CONCENTRATION,
33% comln9 from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=158 ฑ 10 gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION 0 20 40 60 80100 1,200 1,300 1,400 0 100200 300400 0 200
350
400
450
UJ
O
u_
OT 50ฐ
Q
3
g
3 550
UJ
CD
1-
LJJ
UJ
- 600
I
1
0.
UJ
Q
650
700
yen
aq
syi
,_.ฃ
1 =
-
- ^
_ ^
- -
_ i
_ ^
2
-^
er^
jiter
tern
_J=
^
^^
^^~
-
_-/-
^^
_jr
s~~~~
^
^^z
ฐ^^^
^
^^=
=-
^
^c^
c^
"
^
^
f-5'^
*
= __
5=^
<=^
ซ^^
~~r
^
^ST"
^
^
^35
r=>
^*
J>
1 ^s
_^-^^
iz==-
>
:^-
=
-
-
-
-
_
-
:
-
-
;
-
-
_
-
~
_
-
"
_
-
-
.
-
-
-
11 %
Y
3.'
4.!
17
8."
i
%
0
5!
oou
400
450
500
550
-
_
-
_
'
600 h
r
650 h
f
700
vcn
-
c
a
c
(C
e
Pt
fo
rfc
at
ra
3d
et
?
ซ
t
j
\5
.5
"/
"A
-
-
-
-
-
_
-
oou
400
450
500
550
600
650
700
vcn
Specific conductance
* PH ;
Note: Well-head
concentrations are
~~ represented by ~
hollow markers at
the depth of the
pump intake.
_ :
-
_
t T
j
-oT ' \ ~
~*~\ ' f
7 Tฐ ui
1 III
_ / 1 f S
B*^ ฎ
-
TJ
i
oou
400
450
500
550
600
650
700
vcn
Magnesium
4 Calcium
Sodium
Potassium
_ _
-
_
III ฃA ฃ
52.' IJn 3^k ง-
1 ll . 3<
III A <
_
] I ^/y* '
-
I
oou
400
450
500
550
600
650
700
vcn
400 600 0 30 60 90 0 2,000 4,000 6,000
I
Carbonate
* Chloride
Sulfate
Bicarbonate
_
-
_
-
Carbonate
/
/
/
<
t i <
il
O
_
ft m
ป 3
ffi >
!P
_ 1
-
_
'ffitl f>
.i 11 Is
I' T3 1 =
'3 ? t
r /
i i 4
1
; Chromium
-
l l
oou
400
450
500
550
600
650
700
vcn
A Strontium
^ Barium
1 Boron
_
-
_
ft T*
- |H fS_
/
ft T
/
- i 1 -
*^o cf
Barium
-
i
40 60 BQL 10 20 30 0 100 200 300
INM^rRnRnFNTrFNc; PERCENTAGE OF PH, IN CONSTITUENT CHLORIDE AND CONSTITUENT CONSTITUENT
MM MIOKUKUC \i i ucixiCD TOTAL FLOW STANDARD UNITS CONCENTRATION CARBONATE CONCENTRATION, CONCENTRATION
KtK MUUK |N M|LL|GRAMS CONCENTRATION IN MICROGRAMS IN MICROGRAMS
PER LITER IN MILLIGRAMS PER LITER PER LITER
PER LITER
-------
Appendix 5E. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 13, August
2004 [ng/L, micrograms per liter; API, American Petroleum Institute; NQ, not quantifiable; %, percent; Q, estimated well yield in
gallons per minute (gpm); EPA MCL, Environmental Protection Agency maximum contaminant level for arsenic].
KPLANATION
Perforated interval showing ^ Pumping
I ^percent flow contribution water level spEc|p|c SQD|UM BICARBONATE VANADIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
33% comln9 from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=186 ฑ 12 gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION nnn 0 20 40 60 80 100 nnn500 55ฐ 60ฐ 0 100 200 300_^n 0 100 200 300 400 nnn 0 100 200 300 400_^n 0 2,000 4,000
ฃ
=
1
?
f.
*
'- <
: ^
f
--^
v.
~^^
__^
^-- '
^3
i
jT
<^
~-j
^=>
2;
~^^
^~~
f.
^
$
;=ป
---
De
aq
sys
^
^~
"^^
^
3.
.
^f^~
-*
ep
jifer -
tern .
-
-*-
8.6 %
T
4.'
8.1
1(
3!
31
<
j
k
ouu
350
400
450
500 i
550 1
600
650 f
vnn
~.
-
-
ouu
350
400
450
500
550
600
650
vnn
Specific conductance
* pH
Note: Well-head
concentrations are
represented by
hollow r
narkers at
the depth; of the
pump intake.
-
o
ฃ" CD
a a
QJ ^v
1 ฐ
mr
//
/ /
\/
\
1 f
/
/
"^ \
>>/
ouu
350
400
450
500
550
600
650
vnn
Magnesium
^ Ca cium
A Sodum
- ^
\
- '
f
CD
E'
3
r\
\
i.
M .
"UJ <
a
3
1 1
\
>
o
L
3
>
ouu
350
400
450
500
550
600
650
vnn
1
Carbonate
* Chloride
Sulfate
A Bicarbonate
Carbon a
\
' '
_.. i
1 O I
^
g
CD
1^
1
1
A
?
I ^
1
-
-
e
' -
CD
^S
:
%
CD"
i.
ouu
350
400
450
500
550
600
650
vnn
1
; ^ Arsenic
Selen um
A Vanad um
Chrom um
; j, m
; ง 3
:= |
'
-------
Appendix 5F. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 15, January
2005 [ng/L, micrograms per liter; NQ, not quantifiable; %, percent; Q, estimated well yield in gallons per minute (gpm); BQL, below
practical quantitation limit; EPA MCL, Environmental Protection Agency maximum contaminant level for arsenic].
EXPLANATION
Perforated interval showing ^ Pumping
L^ percent flow contribution water level spEc|p|c SOD|UM BICARBONATE VANADIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
33% comln9 from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=256 ฑ 13 gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION 0 20 40 60 80100 500 600 700 0 50 100 150200 0 100 200 300400 0 80 160 240 0 1,250 2,500
300
350
LU 400
o
1
in
a
< 450
-1
g
0
i
UJ
CD
h-
LJJ 500
LL
E
Q_
UJ
ฐ 550
600
ccri
De
aq
sy
- <
- f
- <~^
- <
^"
"C
c
" /"
ep
jifer
stem
.-'
^
^~~~^
$
^~
- "
^
.c^^
^
~~~
=j
^^>
^
,
_
^5
^>
^
~~^
C
^^_^
5
^^
-
Jj^
_,
V
^>
^
X
J>
^
=
^3
^^
^^
~>
r
~ ^
> -
u
Q.
'Q.
C
E
3
0
U
ฃ
u
c
T
in
14%
^
5.!
12
10
.
4%
ouu
350
400
450
500
550
-
-
-
-
c
QJ
1
Q
ฃ3
600 r i
(
A
1
9
"/
ฐX
-
-
-
-
-
ouu
350
400
450
500
550
600
f^cr\
Specific conductance
*PHi
Note: Well-head
concentrations are
represents
d by
hodow markers at
the depth of the
pump intake.
-
-
- <
\
\ '
1|\
|l
-
*
i
-
-
-
%
V
f
/
i
L
v^.
II
ouu
350
400
450
500
550
600
f rn
1
Magnesium
^ Calcium
Sodium
Potassium
-
-
-
TJ
O_
ฃ.
- (
1 T t f "
/ /
' / \/
/
/ A
ts T "
s 8 M
3 a a
c' 3 3
3
i rT
ouu
350
400
450
500
550
600
ฃMZI~I
1 '
Carbonate
* Chloride
Sulfate
Bicarbonate
-
-
-
Sulfate
/
-
-
-
/ Carbonate
1 /
-t W 1
\\
u
1 ^ '
\
i V
1
Q.
CD
\ ^
D
-
CD
S
|
ff -
\
i.
&
ouu
350
400
450
500 (
1
550
1
600 ,
(
r*cr\
; '
; ^ Arsenic
: Selenium
A Vanadium
Chrom um
-
I?
:" P
:
-------
Appendix 5G. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 18, January
2005 [|o,g/L, micrograms per liter; NQ, not quantifiable; %, percent; Q, estimated well yield in gallons per minute (gpm); EPA MCL,
Environmental Protection Agency maximum contaminant level for arsenic].
EXPLANATION
Perforated interval showing ^ Pumping
L^ percent flow contribution water level spEc|Rc SOD|UM BICARBONATE VANADIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
33% coming from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=159ฑ10gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION 0 20 40 60 80 100 550 575 600 0 50 100 150 200 0 100 200 300 400 0 50 100 150 200 0 2,000 4,000
Qfifi r*r\r\ i~~ nr\r\ r*r\r\ r*r\r\ r*r\r\ r*r\r\
300
350
LLI 400
o
a:
in
9. 450
?
^=.
^^^
?
~^>
v^
V
^j^
~~^
~~~~ -3
JS
^T
^
-
--
De
aqi
I^sye
->
;>
^=-
^
<
ep -
jifer -
tern _
-
-
-
-
~
-
-
-
-
-
-
~
-
X,
17%
Y
f
3.;
8.;
\t
%
r
10%
A
T
29%
ouu
350
400 -
450
500
550 1
600
650 1
vnn
i)
w
iu
3.
Q
(
;
5
5
"A
"A
-
-
ouu
350
400
450
500
550
600
650
vnn
Specific conductance
* pH
Note: Well-head
concentrations are
represented by
hollow markers at
the depth of the
pump intake.
-
f
\
0 15 30 45 60 o 20 40 60 80 100 8.0
-
-
1'
M
T C O
Pi V
\
\
\i
!!
ouu
350
400
450
500
550
600
650
vnn
Magnesium
4 Calcium
Sodium
-
- T' M'O -
1 3
1 i , . >
II A
n
- I y ~
T s T
.IP 1 -
1
ouu
350
400
450
500
550
600
650
vnn
Carbonate
ป Chlorde
Sulfate
B carbonate
-
-
t f ฅ i
O
ง
a
" |
'm
| -
3~
o
CD"
- fi\
1
ouu
350
400
450
500
550
600
650
vnn
;i
^ Arsenic
Selenium
A Vanadium
Chromium
-
A
1
j 9
Q. 3
E" c
W ^ z
| 1 ,
3
- 1 .
3 3
ป
V
1
1
/
1
\
?>
1
if p
i r
ouu
350
400
450
500
550
600
650
vnn
l
Strontium
^ Barium
Boron
-
M \ -
\
g ro fe
1
7
i^-
' ฅ T
T 1
1
..11
1 1 1
8.5 9.0 0 0.5 1.0 1.5 2.0 0 10 20 30 40 05 10 15 20 0 100200 300 400
NATURAL GAMMA PERCENTAGE OF PH IN CONSTITUENT CONSTITUENT CONSTITUENT CONSTITUENT
IN COUNTS PER SECOND TOTAL FLOW STANDARD UNITS CONCENTRATION, CONCENTRATION CONCENTRATION, CONCENTRATION
IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
PER LITER PER LITER PER LITER PER LITER
-------
Appendix 5H. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 23, April-May
2004 [ng/L, micrograms per liter; NQ, not quantifiable; %, percent; Q, estimated well yield in gallons per minute (gpm); EPA MCL,
Environmental Protection Agency maximum contaminant level for arsenic].
EXPLANATION
Perforated interval showing
percent flow contribution
67% Percentof well yield
goo/ coming from above
0 and below the pump
WELL CONSTRUCTION
300
350 -
400 -
K.
=>
K>
Q
Z
<
450 -
LU
CO
- 500 -
LU
Q
550 -
600
01234
NATURAL GAMMA,
IN MICROROENTGENS
PER HOUR
^ Pumping
water level
. SI
DECIFIC SOC
IUM BICARB
ONATE VANA
DIU
M BORON
o Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
Q=242ฑ16gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
0 20 40 60 80 100 700 800 900 1,000 0 125 250 0 200 400 600 800 0 300
300
400
450
(
-
-
U
Jl
U
3.
13
D
500 1
550 F
3UU
350
400
450
500
550
finn
Specific conductance
ปpH
Note:
Well-head
concentrations are
rep re
hollov
sented by
v markers at
- the depth of the
pump intake.
1
~ \
-
/]
i
1 ,
9\
%\
%\
\
i%\
<
^
i
-
I
1
Wellhead CO
samples
i!
3UU
350
400
450
500
550
finn
Magnesum
Calcium
Sodium
Potassium
-
-
P
(O
1
3
-
1
o<
!
1 4
"
1 1
<
-
-
I
f -
|
-o
la.
If
\l
\*
>
-
"
i i
o
Q.
c"
3
j i -
( 1
n oo A
3UU
350
400
450
500
550
finn
Carbonate
* Chloride
Sulfate
A Bicarbonate
4
O
1
E.
CD
"
O 1
Carbonate
i
1
I
H* |
-
-
rj
4
-
\
i CD 1 1
S" w
3- S;
O EO
3 CD
L CD" 1
1 1 -
A 4
OO
A n
3UU
i
600 0 1,000 20003,000
; ^ Arsenic
: Selenium
A Vanadium
Chromium
350
i 5
! =
0
1
-
Chromium
400
450
500
550
finn
/
f T f
no *
en
(F
3
10 1 J
'IV
10 <>
>
CD
I"
<
10 ซ '
I* i
DOC
_
/
L
-
-
V
1
1
A
3UU
350
400
450
500
550
finn
i
Strontium
^ Barium
1 Boron
-
-
j
-
k t P
CO \tP /
=r \w
1 1 /
1 V f
_
\
\
/t
/ s
f I
T
i -
I
n
i
0 20 40 60 80 100 7.0 8.0 9.0 10.0 0.00 1.25 2.50 0 20 40 60 80 0 150 300 0 100 200 300
PERCENTAGE OF pH, IN CONSTITUENT CONSTITUENT CONSTITUENT CONSTITUENT
TOTAL FLOW STANDARD UNITS CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
PER LITER PER LITER PER LITER PER LITER
-------
Appendix 51. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 31, March
2005 [ng/L, micrograms per liter; API, American Petroleum Institute; NQ, not quantifiable; %, percent; Q, estimated well yield in
gallons per minute (gpm); EPA MCL, Environmental Protection Agency maximum contaminant level for arsenic].
EXPLANATION
Perforated interval showing ^ Pumping
I ^percent flow contribution water level SPECIFIC SODIUM BICARBONATE VANADIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION
33% coming from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=242ฑ16gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION 0 20 40 60 80100 600 650 700 0 100 200 300 0 100 200 300400 0 150 300 450 600 0 2000
300
350
LJ 400
O
LJ_
cc
co
i 450
I
O
i
LLI
H 500
LJJ
LU
LL
t 550
LJJ
O
600
650
- Dee
- aqui
- syst
{__
^
- <---
j5
f
- -^
- 4
; j
; ^
y<.
er
3m
=^^_
r-
-^
^
s>
^
-
d
'*""""
^r=
_i=>
s
.
~>
^
Js?
^=~
:=
f-
^3,
-=i
.
-
-
-
:
-
-
-
-
.
-
.
-
~
.
.
-
-
;
a
c
re
u
.c
u
c
T
CM
11 %
_
OUU
350
"
QJ
0>
400 r-
.
10-% I
14%
15
%
450 j
rp
1.0%' 50ฐ
H
.
c
t
13
i
i
550
-
N
Q
%
o/.
650
Tnn
i
^
1
g
ฐ/
_
-
-
ouu
350
400
450
500
550
600
650
~7r\r\
Specific conductance
* pH
Note: We
ll-head
concentrations are
represented by
hollow markers at
the depth of the
pump intake.
_
i
-
-
T
-o\
1
1 <
ol
If -
L ,
/ \
1
ouu
350
400
450
500
550
600
'650
~7r\r\
l i
Magnesium
4 Calcium
Sodium
Potassium
_
-
-
I , . y
- <[i ,. *
i >i i , \
o3 ^ \
6? | a \ฃ
C/l CD :=- \5~
=01 C \C
_l | 3 \3
u . . V
1 ]
"
ouu
350
400
450
500
550
600
650
~7r\r\
l
Carbonate
* Chloride
Sulfate
A Bicarbonate
_
t t A i
o ฃ>
OUU
350
400
450
1
- | cf - 500
ฐ- ffl 1
CD S-
1
)
- i(f I 1
TT il '
CO
s g
1 3- =
o S
= CD
1
u ,
_ If 1,
'
1 550
600
650
~7r\r\
; i
; ^ Arsen c
Selen urn
A Vanadium
Chromium
> m
1 >
? P
1
1 A 4
o
1"
i.
3
) A m^ <
lป A '
w <- \
D 3 \
3 QJ \
-3 3
1 1 A <
1 1 A <
1 "
0
"
\ -
./
l
ouu
350
400
450
500
550
600
650
~7r\r\
l i
4,0
A Strontium
4 Barium
1 Boron
_
A
-
JL II'
A 1 <
-A m
CO
^ CD
O O
|
Jk II <
Jk | | .
_
-
-
700 ' ' ' ' ' ' ' ' ' ' ' ' *-"-' ' *-"-' ' *-"-' ' *-"-' ' *-"-' ' *-"-'
0 25 50 75 100 0 20 40 60 80 100 8.0 8.5 9.0 0 1 2 3 0 10 20 30 40 0 15 30 45 60 0 100 200 300 4C
NA'iM)AP|L|^Tl<5/IA' PERCENTAGE OF pH, IN CONSTITUENT CONSTITUENT CONSTITUENT CONSTITUENT
IN AM UNI I & TOTAL FLOW STANDARD UNITS CONCENTRATION, CONCENTRATION CONCENTRATION, CONCENTRATION
IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
PER LITER PER LITER PER LITER PER LITER
-------
Appendix 5J. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 33, March
2006 (* indicates that flow contribution was determined by subtracting flow above the pump, calculated using an effective area of
0.21 square foot, from the maximum estimate of well yield) [j-ig/L, micrograms per liter; API, American Petroleum Institute; NQ, not
quantifiable; %, percent; Q, estimated well yield in gallons per minute (gpm); EPA MCL, Environmental Protection Agency maximum
contaminant level for arsenic].
EXPLANATION
Perforated interval showing ^ Pumping
_ฐ] percent flow contribution ~ water level eocr-icir-
oPtdrlo >.
SODIUM BICARBONATE CHROMIUM BORON
67% Percent of well yield ฐ Pump intake CONDUCTANCE, IN CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
33% comln9 from above MICROSIEMENS IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
and below the pump Q=208ฑ13gpm PER CENTIMETER PER LITER PER LITER PER LITER PER LITER
WELL CONSTRUCTION 0 20 40 60 80 100 400 430 460 0 20 40 60 120 150 180
300
350
LU 400
^
tz
O
< 450
g
LU
CD
ffl 500
I 1
x-
1
Q_
LLI
ฐ 550
600
<~
_ >
" i
- I
- \
-<
^
_ /
C
V
*"
>
{_
^
5~J
-~^_^^
^t
~~ _
'
5^
^
^j'
^
^
^
r?
^~"
~~\
<,
_ -s"
cc
^
^^
71
Deep
aquif
syste
f-
="
S
^~^
<
3r
m
-
_
-
_
_
-
-
;
-
-
-
-
-
-
-
-
.
-
-
-
9.8 %
*
10%
7.;
i
1
3
33t %
t
OUU
350
400
-
c
450
500
550
-
-
-
Ci
600 |
*
Jill
HI
J
^
ป7
!3
"A
"/,
-
-
-
-
-
-
ouu
350
400
450
500
550
600
Specific conductance
* pH
Note: Well-head
concentrations are
represented by
~ hollow markers at
the depth of the
pump intake.
-
t
/
o/g
1ฐ
1
J /
* /
\ /
y
4
/x
p
i
ouu
Magnesium
^ Calcium
A Sod um
Potassium
350
400
450
500
550
600
i
1
i i
^
3" 3
fi en
c' c
3 3
1
J
n
A
i
A
'
i
s
T
I
,
1 I
-
-
-
-
,
|
1
-
ouu
350
400
450
500
550
600
ป Chloride
Sulfate
210 240 0 20 40 60 80 100 0 1,000 2,000 3,000
A B carbonate
-
-
1
/
/
\
-
O
g.
CD
< 1
V J
O L_
650 oou oou oou oou
0 20 40 60 80 100 Q 20 40 60 80 100 7.0 8.0 9.0 0 20 40 60 60 75 90
-
-
/ t
/ 1-
j -
S
t
3
, f-
1
c I
1 1
/-
1
ouu
350
400
450
500
550
600
i i i i
I
^ Arsenic |
Selenium n
A Vanadium ฐ
Chromium r=
-
-
AT T
6\\9 I "
> %\ \0 /
I m
1 1
/
y
K 'fe
\ %
\ V
1\\
1 1 1 1
OUU
3
n
350
400
450
500
550
1
600
A Strontium
* Barium
1 Boron
-
-
f f
/
/
/
/ /
-.
m ui
.
u
-
-
n
-
-
uuu uuu
105 120 0 2 4 6 8 10 400 600 800 1 000
NA}KVAPMIMT^A' PERCENTAGE OF pH, IN CONSTITUENT CONSTITUENT CONSTITUENT CONSTITUENT
IN AM UNI I & TOTAL FLOW STANDARD UNITS CONCENTRATION, CONCENTRATION, CONCENTRATION, CONCENTRATION,
IN MILLIGRAMS IN MILLIGRAMS IN MICROGRAMS IN MICROGRAMS
PER LITER PER LITER PER LITER PER LITER
-------
Appendix 5K. Natural gamma-ray log, open-interval (perforation) log, flow contribution, and water quality with depth in Norman Well 36, October
2004 (flow) and June 2005 (water quality) [jJg/L, micrograms per liter; API, American Petroleum Institute; NQ, not quantifiable;
%, percent; Q, estimated well yield in gallons per minute (gpm); BQL, below practical quantitation limit; EPA MCL, Environmental
Protection Agency maximum contaminant level for arsenic].
EXPLANATION
Perforated interval showing
percent flow contribution
Percent of well yield
"coming from above
and below the pump
300
WELL CONSTRUCTION
700
0 20 40 60 80
NATURAL GAMMA,
IN API UNITS
300
350
400
450
500
550
600
650
- Pumping
water level
Pump intake
Q=240ฑ15gpm
0 20 40 60 80 100
SPECIFIC
CONDUCTANCE, IN
MICROSIEMENS
PER CENTIMETER
700
N3
300
350
400
450
500
550
600
650
400
500
600
700
Specific conductance
ป pH
Note: Well-head
concentrations are
represented by
hollow markers at
the depth of the
pump intake.
300
350
400
450
500
550
600
650
SODIUM
CONCENTRATION,
IN MILLIGRAMS
PER LITER
30 60 90 120
700
Magnesium
Calcium
Sodium
300
350
400
450
500
550
600
650
BICARBONATE
CONCENTRATION,
IN MILLIGRAMS
PER LITER
0 100 200 300 400
700
Carbonate
ป Chloride
Sulfate
Bicarbonate
300
350
400
450
500
550
600
650
VANADIUM
CONCENTRATION,
IN MICROGRAMS
PER LITER
I 75 150 225 300
Arsenic
Selenium
Vanadium
Chromium
700
300
350
400
450
500
550
600
650
BORON
CONCENTRATION,
IN MICROGRAMS
PER LITER
0 2,000 4,000
700
Strontium
^ Barium
Boron
0 20 40 60 80 100
PERCENTAGE OF
TOTAL FLOW
7.0
8.0
9.0
pH, IN
STANDARD UNITS
10 20 30 40
CONSTITUENT
CONCENTRATION,
IN MILLIGRAMS
PER LITER
0
5 10 15 20
CONSTITUENT
CONCENTRATION,
IN MILLIGRAMS
PER LITER
BQL 25 50 75 100
CONSTITUENT
CONCENTRATION,
IN MICROGRAMS
PER LITER
0 1,000 2,000
CONSTITUENT
CONCENTRATION,
IN MICROGRAMS
PER LITER
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. Shaded rows denote quality-assurance samples [mg/L, milligrams per liter; ug/L,
micrograms per liter; %, percent; uS/cm at 25ฐC, microsiemens per centimeter at 25 degrees Celsius; ฐC, degrees Celsius; NTU,
Nephelometric Turbidity Units; mm Hg, millimeters of mercury; E, estimated below quantitation limit; <, less than quantitation limit;
--, no data]
Well
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
USGS
station number
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
351409097231801
Station name
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22DDA1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
09N-02W-22 DDA 1
Quality-
assurance
sample
type
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Replicate
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Date
Nov 172005
NOV172005
Nov 172005
Nov 17 2005
Nov 172005
Nov 17 2005
Nov 172005
Nov 17 2005
Nov 172005
Nov 17 2005
Nov 172005
Jan 132006
Jan 132006
Jan 132006
Jan 132006
Jan 132006
Jan 132006
Jan 132006
Jan 132006
Jan 13 2006
Jan 132006
Jan 13 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Jan 20 2006
Time Depth of pump Sampling Elevation of
intake depth (feet) land surface
(feet) (feet)
1000
1100
1200
1200
1230
1500
1500
1300
1330
1400
1400
0930
0930
1000
1000
1300
1230
1230
1200
1200
1100
1100
0930
0930
1300
1030
1030
1200
1130
1130
1100
1100
610
610
610
610
610
610
610
610
610
610
610
560
560
560
560
560
560
560
560
560
560
560
505
505
505
505
505
505
505
505
505
505
430
470
500
500
550
well head
well head
620
630
660
660
470
470
550
550
well head
580
580
630
630
660
660
470
470
well head
500
500
580
630
630
660
660
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
1161
Specific
conductance,
field
(uS/cm at
25 ฐC)
435
428
441
446
515
588
674
901
551
453
514
869
844
732
445
537
855
1,003
995
980
PH,
field,
standard
units
6.68
7.92
7.95
7.96
8.18
8.56
8.75
8.76
8.21
8.35
8.48
8.88
8.88
8.86
7.97
8.61
8.66
9.07
9.15
8.85
Temperature, Turbidity,
water field
(ฐC) (NTU)
.12
1.62
.23
1.26
17.5 1.02
.92
6.32
.48
.96
.58
17.5 .53
3.33
4.15
4.10
2.16
17.5 1.14
2.34
1.23
3.92
4.28
Barometric Dissolved Dissolved
pressure oxygen, field oxygen, field
(mm Hg) (mg/L) (%)
728.4
738.4
738.4
738.4
738.4 6.02 63.0
738.4
738.4
738.4
719.8
719.8
719.8 E4.08 E42.7
719.8
719.8
719.8
725.7
725.7 5.37 56.2
725.7
725.7
725.7
725.7
Calcium,
filtered
(mg/L)
9.02
6.72
7.41
7.41
6.77
^^H
4.68
4.33
4.59
6.82
7.24
7.23
6.93
4.17
4.18
4.22
4.53
6.65
6.78
5.18
5.07
3.46
3.62
4.00
Calcium,
unfiltered
(mg/L)
"
"
--
M
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
Sampling Magnesium,
depth filtered
(feet) (mg/L)
430
470
500
550
well head
well head
620
630
660
470
470
550
550H
well head
580
580
630
660
660
470
well head
500
5CX>H
580
630
660
660
7.22
5.14
5.66
5.67
5.05
3.20
2.84
3.15
5.24
5.56
5.53
5.31
2.90
2.88
2.91
3.35
5.10
5.01
3.59
3.48
2.18
2.31
2.85
Magnesium, Sodium,
unfiltered filtered
(mg/L) (mg/L)
81.4
89.0
87.5
88.0
105
129
146
199
86.8
88.9
88.6
104
190
188
182
161
88.9
108
181
181
218
212
Sodium Sodium,
adsorption unfiltered
ratio (mg/L)
4.90
6.29
5.89
5.92
7.44
11.3
13.4
17.5
6.08
6.04
7.23
17.5
17.3
16.7
14.0
6.31
7.67
15.0
15.2
22.6
19.8
Potassium, Potassium, Bicarbonate,
filtered unfiltered unfiltered
(mg/L) (mg/L) (mg/L)
1.35
1.10
1.16
1.17
1.11
.850
.770
.771
1.18
1.20
1.18
.768
.754
.767
.895
1.13
1.14
.852
.669
.655
.742
256.5
255.7
259.3
259.3
280.3
303.3
316.2
375.1
250.0
254.5
285.4
354.9
358.4
325.6
257.0
280.1
358.9
411.1
409.1
387.2
Carbonate,
unfiltered
(mg/L)
1.1
1.5
1.6
1.6
3.3
10.2
12.6
19.1
3.7
1.5
3.9
27.7
20.6
21.0
1.5
5.9
18.0
19.0
18.8
24.0
Acid
neutralizing
capacity
(mg/L as
CaCO3)
212.3
212.3
215.3
215.3
235.5
^^m
265.9
280.5
339.7
211.3
211.3
240.6
337.6
328.5
302.3
213.3
239.6
324.5
369.0
366.9
357.9
Sulfate,
unfiltered
(mg/L)
10.6
10.0
10.4
E.186
E.172
"
E.228
20.0
32.2
32.3
11.4
10.7
13.9
32.3
30.4
22.7
22.9
10.1
15.2
31.5
40.9
40.1
38.3
Chloride,
unfiltered
(mg/L)
3.41
2.14
3.04
<1.00
<1.00
<1.00
22.8
55.6
56.3
2.63
3.25
9.26
45.6
42.3
32.3
32.2
2.42
12.8
44.7
63.1
61.5
61.5
62.0
Bromide,
unfiltered
(mg/L)
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
E.150
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
E.098
E.126
E.113
Iodine,
unfiltered
(mg/L)
<.025
<.025
<.025
^^
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
Nitrite, Nitrite plus nitrate, Ammonia,
unfiltered unfiltered unfiltered
(mg/L as N) (mg/L as N) (mg/L as N)
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
E.015
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
.283
.244
.256
.269
.254
.258
.279
.272
.259
.262
.256
.269
.255
.258
.311
.305
.233
.260
.261
.236
.245
.245
.245
<.100
.163
E.019
<.100
E.074
E.021
E.020
E.022
<.100
--
<.100
M
<.100
<.100
.260
M
.268
<.100
<.100
<.100
E.051
<.100
<.100
.318
<.100
<.100
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
Sampling
depth
(feet)
430
470
500
550
well head
well head
630
660
660
470
550
550
well head
580
630
660
660
470
470
580
630
660
660
Orthophosphate,
unfiltered
(mg/L as P)
E.014
E.014
.022
E.019
.028
.036
.045
.049
E.019
E.019
.020
.039
.038
.031
E.019
.051
.047
.047
Aluminum, Aluminum,
filtered unfiltered
(ug/L) (ug/L)
174
157
134
148
174
212
204
..
192
150
146
186
193
188
214
194
204
153
156
--
Antimony, Antimony,
filtered unfiltered
(ug/L) (ug/L)
E5
E4
E4
<10
E3
..
E5
E4
E5
E3
E4
^^0
<10
<10
^^^^^H
Arsenic,
filtered
(ug/L)
1.24
1.76
1.70
1.84
8.11
36.5
52.0
--
1.59
1.73
6.54
34.4
31.9
26.4
1.58
1.59
40.3
39.5
38.4
--
Arsenic, Arsenate, Arsenite, Dimethyl- Monomethyl-
unfiltered filtered filtered arsinate, arsonate,
(ug/L) (ug/L as As) (ug/L as As) filtered filtered
(ug/L as As) (ug/L as As)
-- <10 <10 <10 <10
<10 <10 <10 <10
<10 <10 <10 <10
26 <10 <10 <10
37 <10 <10 <10
..
<10 <10 <10 <10
^^ <10 <10 <10 <10
30.5 <10 <10 <10
24.8 <10 <10 <10
16.6 <10 <10 <10
<10 <10 <10 <10
?6? 10 10 10
< < <
32.7 <10 <10 <10
33.5 <10 <10 <10
16.6 <10 <10 <10
31 .8 <10 <10 <10
Barium,
filtered
(ug/L)
433
399
384
393
410
395
437
456
382
381
419
362
347
391
435
387
317
354
Barium, Beryllium,
unfiltered filtered
(ug/L) (ug/L)
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
Sampling Cadmium,
depth filtered
(feet) (ug/L)
430
470
500
550
well head
620
630
660
660
470
550
550
well head
580
630
630
660
660
470
470
well head
500
580
630
630
660
660
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
Cadmium, Chromium, Chromium, Cobalt,
unfiltered filtered unfiltered filtered
(ug/L) (ug/L) (ug/L) (ug/L)
64
66
66
66
70
66
66
85
67
66
^^^^^^
68
81
78
66
67
69
88
94
96
96
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
E1
<3
<3
<3
<3
<3
<3
Cobalt, Copper, Copper, Iron(ll),
unfiltered filtered unfiltered filtered, field
(ug/L) (ug/L) (ug/L) (mg/L)
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
.13
.12
.15
.26
.12
.07
.06
.20
.01
.09
.03
.01
.01
.18
.20
.05
.09
.09
.07
.14
Iron,
filtered, field
(mg/L)
.23
.33
.15
.44
.19
.22
.28
.51
.04
.12
.10
.09
.06
.64
.23
.11
.15
.32
.11
.15
Iron, Iron, Lead, Lead, Manganese,
filtered unfiltered filtered unfiltered filtered
(ug/L) (ug/L) (ug/L) (ug/L) (ug/L)
86 -- <10
75 -- <10
64 -- <10
82 -- <10
80 -- <10
81 -- <10
132 -- <10
136 -- <10
92 -- <10
69 -- <10
69 ^^H <1ฐ
85 -- <10
92 -- <10
110 -- <10
117 -- <10
86 -- <10
77 -- <10
96 -- <10
94 -- <10
1 25 -- <1 0
85 -- <10
85 -- <10
E1
<3
<3
<3
<3
<3
E1
E2
<3
<3
<3
<3
<3
E1
E1
<3
<3
<3
<3
<3
<3
<3
Manganese, Molybdenum, Molybdenum, Nickel, Nickel,
unfiltered filtered unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L) (ug/L) (ug/L)
<3
E2
E2
4
6
8
11
23
E2
E2
E2
6
<23
21
11
E3
6
23
23
31
28
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
--
--
"
"
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
05
Sampling
depth
(feet)
430
470
500
500
550
well head
well head
620
630
660
660
470
550
550
well head
580
580
630
660
660
470
470
well head
500
500
580
630
630
660
660
Selenium, Selenium,
filtered unfiltered
(ug/L) (ug/L)
E6
E7
E6
E9
E10
E12
14
29
E9
E4
E6
E11
22
21
E11
..
E10
E9
21
20
29
29
"
27
Silver,
filtered
(ug/L)
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
--
<3
E1
<3
E1
E1
<3
<3
Silver, Strontium, Strontium,
unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L)
247
1 87
205
205
1 86
117
1 04
116
1 88
1 97
1 97
1 88
1 04
1 03
1 04
117
..
1 83
1 85
1 27
88
89
1 06
Thallium,
filtered
(ug/L)
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
--
<20
<20
<20
<20
<20
<20
Thallium, Titanium,
unfiltered filtered
(ug/L) (ug/L)
91
80
72
80
88
84
112
108
101
76
76
96
100
101
98
108
..
97
86
90
107
80
80
Titanium, Vanadium, Vanadium,
unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L)
13
19
19
21
83
262
354
460
18
19
19
73
382
382
363
304
..
18
83
315
451
457
425
Zinc, Zinc, Uranium, Uranium,
filtered unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L) (ug/L)
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
..
<17 -- <20
<17 -- <20
102 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
Organic
carbon,
filtered
(mg/L)
E.353
.603
.641
.638
E.233
<.500
<.500
<.500
E.365
"
1.09
<1.00
-
<1.00
1.63
1.63
E.779
<1.00
E.843
^^m
<1.00
E.645
"
<1.00
E.898
E.916
E.838
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
USGS
station number
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
351633097241901
Station name Quality-
assurance
sample
type
09N-02W-10BBB1 Blank
09N-02W-10BBB 1
09N-02W-10BBB1
09N-02W-10BBB 1
09N-02W-10BBB1
09N-02W-10BBB 1 Duplicate
09N-02W-10BBB1
09N-02W-10BBB 1
09N-02W-10BBB1 Duplicate
09N-02W-10BBB
09N-02W-10BBB
09N-02W-10BBB
09N-02W-10BBB
09N-02W-10BBB
09N-02W-10BBB
09N-02W-10BBB
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
09N-02W-10 BBS
Duplicate
Duplicate
Duplicate
Duplicate
Blank
Duplicate
Duplicate
Duplicate
Duplicate
Duplicate
Date
Sep 28 2005
Sep 28 2005
Sep 28 2005
Sep 28 2005
Sep 28 2005
Sep 28 2005
Sep 28 2005
Sep 28 2005
Sep 28 2005
Nov 3 2005
Nov 3 2005
Nov 3 2005
Nov 3 2005
Nov 3 2005
Nov 3 2005
Nov 3 2005
Nov 3 2005
Nov 3 2005
Jan 182006
Jan 182006
Jan 182006
Jan 182006
Jan 182006
Jan 182006
Jan 182006
Jan 18 2006
Jun 122006
Jun 122006
Jun 132006
Jun 132006
Jun 142006
Jun 142006
Jun 152006
Jun 152006
Jun 162006
Jun 162006
Time Depth of pump Sampling
intake depth (feet)
(feet)
0930
1400
1300
1600
1700
1700
1500
1100
1 100
1000
0900
1500
1100
1100
1300
1300
1400
1400
0900
0901
0902
0903
0903
0904
0905
0910
1100
1100
1000
1000
1630
1630
1430
1430
0900
0900
650
650
650
650
650
650
650
650
650
590
590
590
590
590
590
590
590
590
590
590
590
590
590
590
590
590
600
600
600
600
600
600
600
600
600
600
520
595
645
well head
well head
660
670
670
520
575
well head
595
640
640
670
670
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
Elevation of
and surface
(feet)
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
1080
Specific
conductance,
field
(uS/cm at
25 ฐC)
453
493
508
546
854
839
453
447
456
461
474
540
567
567
567
509
545
556
554
555^
PH,
field,
standard
units
7.73
8.12
8.27
8.55
9.12
8.94
7.26
7.63
7.39
7.74
7.84
8.58
8.48
8.48
8.48
8.19
8.43
8.41
8.41
8.44
Temperature, Turbidity, Barometric Dissolved
water field pressure oxygen, field
(ฐC) (NTU) (mm Hg) (mg/L)
5.01 735.3
1.65 735.3
2.31 735.3
18.0 .76 735.3 5.92
1.46 735.3
.79 735.3
3.17 730.5
.47 730.5
17.6 .49 730.5 6.74
.79 730.5
.71 730.5
11.4 730.5
17.6
17.6
17.6
18.3 -- 737.7 5.64
18.1 -- 737.7 5.61
18.1 -- 737.7 5.64
18.1 -- 737.7 ^^^_
1^5 -- 737.7 ^&58^
Dissolved Calcium,
oxygen, field filtered
(%) (mg/L)
.419
23.8
14.0
12.9
62.7 10.3
2.83
4.81
25.9
25.9
70.5 22.5
21.5
19.6
8.83
--
10.5
10.1
^60 1&^^
59.5 11.9
59.8 11.4
60.5 11.3
"
59.7 ^^^^!
Calcium,
unfiltered
(mg/L)
-
^^H
-
10.4
;:
^^^_
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
Sampling Magnesium,
depth filtered
(feet) (mg/L)
520
595
645
well head
660
670
670
520
575
well head
595
640
670
670
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
<.067
19.0
10.8
9.9
7.81
1.98
3.77
--
21.1
21.0
18.2
17.4
15.5
6.97
^^^^g
7.97
7.50
E.023
12.9
9.23
9.24
8.8
8.62
8.6
Magnesium, Sodium,
unfiltered filtered
(mg/L) (mg/L)
1.1
41.3
76.8
84.9
108
187
178
34.8
35.7
48.4
105
7.83
7.98
113
113
84.1
100
100
98.9
100
Sodium
adsorption
ratio
1.53
3.75
4.32
6.18
20.9
14.8
1.23
1.26
1.84
2.04
2.49
6.41
6.40
6.57
..
3.78
5.29
5.25
5.41
5.39
5.47
Sodium, Potassium, Potassium,
unfiltered filtered unfiltered
(mg/L) (mg/L) (mg/L)
E.045
2.39
1 .86
1 .68
1.37
.474
.747
2.42
2.50
2.32
1.39
113 -- 1.25
113 1.28
1.29
1.28
1.67
1.36
1.29
1.28
1.35
Bicarbonate, Carbonate, Acid Sulfate,
unfiltered unfiltered neutralizing unfiltered
(mg/L) (mg/L) capacity (mg/L)
(mg/L as
CaC03)
<1.00
258.8 .9 213.8 9.59
284.4 1.1 235.0 12.3
291.8 2.2 243.1 12.8
313.8 5.9 267.4 12.9
363.2 34.4 356.3 14.9
374.7 23.5 347.2 14.9
253.3 .6 208.7 9.26
256.1 .8 211.3 9.52
264.8 .7 218.4 9.40
264.8 .7 218.4 9.0
268.4 2.5 224.4 9.39
294.2 8.5 255.8 9.80
11.3
12.7
12.9
12.7
12.7
Chloride,
unfiltered
(mg/L)
<1.00
5.46
4.88
6.67
12.7
36.9
36.7
36.7
5.45
5.60
5.72
5.87
5.84
6.04
7.33
--
--
11.9
11.7
11.5
11.5
11.4
Bromide,
unfiltered
(mg/L)
<.250
<.250
<.250
<.250
<.250
E.156
E.108
E.130
<.250
E.108
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
<.250
Iodine,
unfiltered
(mg/L)
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
<.025
--
--
<.025
<.025
<.025
<.025
<.025
<.025
Nitrite, Nitrite plus nitrate
unfiltered unfiltered
(mg/L as N) (mg/L as N)
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
<.100
^^M
<.100
<.100
<.100
E.065
.427
.333
.350
.375
.393
.748
.751
.463
.459
.456
.453
.459
.465
.458
0.5
0.434
0.436
^^^m
0.435
^^^
0.438
0.436
, Ammonia,
unfiltered
(mg/L as N)
<.100
<.100
<.100
<.100
<.100
<.100
.444
<.100
E.014
E.026
E.036
E.049
<.100
<.100
;;
^m^m
^^
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
Sampling Orthophosphate,
depth unfiltered
(feet) (mg/L as P)
520
595
645
well head
660
670
670
520
575
well head
595
595
640
640
670
670
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
E.015
E.017
.020
.021
.028
.056
.051
.050
E.015
E.014
E.013
E.014
E.014
E.014
E.019
0.024
0.025
0.024
0.025
0.024
0.024
Aluminum, Aluminum,
filtered unfiltered
(ug/L) (ug/L)
97
223
274
211
237
267
255
207
219
293
195
219
192
<57
<57
<57
E49
<57
E20
E25
<57
E25
Antimony,
filtered
(ug/L)
E4
E3
:1ฐ
E7
E5
E8
E5
E4
E5
E7
E3
E3
E4
E3
<10
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
Sampling Cadmium, Cadmium,
depth filtered unfiltered
(feet) (ug/L) (ug/L)
520
595
645
well head
well head
660
670
670
520
575
well head
595
595
640
670
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
Chromium,
filtered
(ug/L)
E1
59
78
82
91
123
122
58
57
57
50
54
56
-
90
90
<3
78
89
90
89
89
Chromium, Cobalt,
unfiltered filtered
(ug/L) (ug/L)
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
91
E1
<3
<3
<3
<3
<3
<3
<3
Cobalt, Copper, Copper, Iron(ll),
unfiltered filtered unfiltered filtered, field
(ug/L) (ug/L) (ug/L) (mg/L)
<20
<20 -- .23
<20 -- .06
<20 -- .10
<20 -- .03
<20 -- .20
<20 -- .06
<20 -- .17
<20 -- .11
E9 -- .08
<20 -- .28
<20 -- .31
<3 -- <20
<20
<20
<20
<20
<20
<20
<20
<20
Iron, Iron, Iron, Lead, Lead, Manganese, Manganese,
filtered, field filtered unfiltered filtered unfiltered filtered unfiltered
(mg/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L) (ug/L)
60 -- <10
.46 100 -- <10
.15 122 -- <10
.29 96 -- <10
.07 107 -- <10
.48 121 -- <10
.11 113 -- <10
.23 92 -- <10
.11 95 -- <10
.08 134 -- E3
.42 87 -- <10
.42 103 -- <10
<20 -- <1(
<20 -- <10
<20 -- <10
E17 -- <10
<20 -- <10
<20 -- <10
<20 -- <10
<20 -- <10
<20 -- <10
E1
<3
<3
<3
<3
<3
<3
E2
<3
E1
<3
<3
) -- <3
<3
<3
<3
<3
<3
<3
<3
<3
Molybdenum,
filtered
(ug/L)
<3
3
5
6
7
14
13
E3
<3
4
3
3
E3
6
5
<3
4
5
5
6
5
Molybdenum, Nickel, Nickel,
unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L)
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
5 -- <3
<3
<3
<3
<3
<3
<3
<3
<3
-------
Appendix 6. Chemical analyses of ground-water samples and quality-assurance samples collected after well modification in two selected public-
supply wells, Norman, Oklahoma, 2005-2006. (continued)
Well
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
Sampling
depth
(feet)
595
645
well head
660
670
670
520
575
well head
595
640
670
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
well head
Selenium, Selenium,
filtered unfiltered
(ug/L) (ug/L)
27
30
47
119
114
..
E9
E9
E11
E6
E9
15
__
__
__
44
48
44
<13
43
49
51
51
49
Silver,
filtered
(ug/L)
E2
<3
E1
<3
<3
<3
--
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
<3
Silver, Strontium, Strontium,
unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L)
E2
372
341
273
67
118
..
663
664
584
550
502
223
__
__
__
<3 274
277
278
E1
413
304
292
285
284
Thallium,
filtered
(ug/L)
<20
<20
<20
<20
<20
<20
--
E8
E10
E8
E10
E8
<20
-
-
-
<20
<20
<20
E7
<20
<20
<20
E7
Thallium, Titanium,
unfiltered filtered
(ug/L) (ug/L)
60
150
114
127
148
139
..
109
113
145
104
117
101
__
__
__
<20
E2
<3
<3
<3
<3
<3
<3
<3
Titanium, Vanadium, Vanadium,
unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L)
<7
21
76
273
1 ,040
955
..
E6
E6
25
18
29
1 07
__
__
__
<3 -- 281
281
272
<7
257
269
271
270
271
Zinc, Zinc, Uranium, Uranium,
filtered unfiltered filtered unfiltered
(ug/L) (ug/L) (ug/L) (ug/L)
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
<17 -- <20
..
<17 -- <20
<17 -- <20
E10 -- <20
E5 -- <20
<17 -- <20
<17 -- <20
__
__
__
<17 -- 23
<17 -- 22
<17 -- 23
<17 -- <20
E14 -- E14
E8 -- E19
E6 -- E20
E6 -- E19
E6 -- E20
Organic
carbon,
filtered
(mg/L)
E.463
.570
E.487
<.50
E.449
3.47
3.61
<.50
<.50
<.50
E.261
1.52
.583
-
-
-
--
-
-
-
--
-------
-------
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