January zOll I www.epa.gov/ada
United States
Environmental Protection
Agency
                Mississippi  Embayment Regional
                Ground Water Study
National Risk Management Research Laboratory, Ada, Oklahoma 74820

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               Mississippi  Embayment Regional
               Ground  Water Study

               Brian Waldron
               University of Memphis, Department of Civil Engineering,
               Ground Water Institute

               Daniel Larsen
               University of Memphis, Department of Earth Sciences

               Robyn Hannigan
               University of Massachusetts at Boston, Department of
               Environmental, Earth and Ocean Sciences

               Ryan Csontos
               University of Memphis, Department of Civil Engineering,
               Ground Water Institute

               Jerry Anderson
               University of Memphis, Department of Civil Engineering,
               Ground Water Institute

               Carolyn Dowling
               Ball State University, Department of Geology

               Jennifer Bouldin
               Arkansas State University, Arkansas Biosciences Institute
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 and managed the research described here under assistance
              agreement EM833253 to the Ground Water Institute located at the University of
              Memphis in Memphis, Tennessee. This report has been subjected to the Agency's peer
              and administrative review and has been approved for publication as an EPA document.

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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 technologi-
cal 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 resto-
ration 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.

Increased water usage in the southeastern United States in the tri-state area of Tennessee, Mississippi and Arkansas poses
a dilemma to ensuring long-term sustainability of the quantity and quality of ground-water resources that underlie the
region. Demand for ground water by agriculture, municipalities and industry are presently stressing the sustainable yield
of the fresh water  aquifers. Instances of ground-water contamination have closed water-treatment facilities; many other
potential contaminant sources could threaten human health. To address these threats, federal, state and local government
have initiated a four-phase research  effort to understand, model, and suggest best management practices for the ground-
water resources in the region.

This report represents the results of the first-phase efforts to address a persistent problem associated with the use of dis-
parate methods and the uncoordinated timing of hydrologic and geologic data collection across state lines, thus creating a
disjoint in the regional understanding of aquifer systems, ground-water migration and usage, and potential contamination
threats on water resources. Similarly, a communication lapse has existed among the states with regard to ground-water
resource planning. By implementing a collaborative, regional approach developed through the first phase, the expecta-
tion is to improve the understanding of the ground-water resources - without the constraint of political boundaries and
disjointed datasets. This will provide capabilities for stakeholders to begin proactively working toward a common goal
of ensuring future ground-water availability without sacrificing the integrity  of the regional ground-water resources.
                                                David G. Jewett, \cting Director
                                                Ground Water and Ecosystems Restoration Division
                                                National Risk Management Research Laboratory

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                                                                          Contents
1.0 Introduction	1
2.0 Background	5
   Regional overview	5
   Arkansas dilemma	5
   Mississippi dilemma	6
   Tennessee dilemma	7
3.0 Project Task Plan	11
4.0 Quality Assurance Project Plan (QAPP) Data Quality Assurance	13
5.0 Results	15
   Perform geologic mapping of the region	15
     Geophysical Log Analysis	16
     Geologic correlation and construction of cross-sections	18
       Geologic Background	19
        The Mississippi Embayment	19
        Tertiary and Quaternary Stratigraphy of the Mississippi Embayment	20
       Hydrostratigraphic Units within the Central Mississippi Embayment	26
       Geologic Database	27
       Stratigraphy	29
       Cross Sections	30
     Structure Contour Maps	34
     Discussion	41
       Lithostratigraphic correlation and uncertainty	41
       Hydrostratigraphy	42
       Regional Structure	43
     Concluding Remarks	43
     Recommendations	44
   Ascertain water quality changes and ground-water contamination threats	45
     Catalog water chemistry variables from disparate datasets	46
     Ascertain temporal ground water quality changes and chart statistical variation
     among measured geochemical variables	50
       Results	52
        Water quality characteristics of the Quaternary Alluvial aquifer	52
        Water quality characteristics of the Upper Claiborne aquifer	59
        Water quality characteristics of the Middle Claiborne aquifer	66
        Water quality characteristics of the Lower Claiborne-Wilcox Aquifer	74
        Discussion of Water Quality in the Tertiary and Quaternary Aquifers	80
     Application of environmental tracers in Tertiary and Quaternary aquifers in the
     Mississippi embayment	83
   Conduct assessment on aquifer parameter values and measurement methodologies. .. 84
     Literature review	84
     USGS historic records	85
   Catalog surface water sources to ground water	89
     Gaging stations	89
     Baseflow conditions	90
       Partial Duration Curves	91

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      Computer Program PART	92
      Program WHAT	94
        Local Minimum Method (LMM)	94
        BFLOW Filter Technique	95
        Eckhardt Filter Technique	95
    Riverbed conductance	97
    Wetlands	100
    Soil data	101
   Diagnose additional sources/sinks of water to the ground-water system  	103
    Ascertain estimation methodologies for ground-water recharge	103
    Evaluate methods for estimating evapotranspiration	104
      Physical sampling methods	105
        Weather Station Derived Penman-Monteith Data	106
        Bowen Ratio	106
        Eddy Covariance	106
      Comparison of Point Measurement Systems	107
      Satellite/Remote Sensing Sampling Methods	107
        MODIS/Landsat	107
        rGIS-et 	109
      Land Cover	109
      Concluding remarks	110
6.0 Summary and Recommendations	113
7.0 References	117
8.0 Appendix Geophysical Logs	131
   Appendix A Plates of Cross Sections	133
   Appendix B Well Log Ranking Chart	143
9.0 Appendix Gages	155
10.0 Appendix Geo-sites	159

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                                                                                 Figures
Figure 1.    MERGWS study area (counties in opaque white), geologic investigative boundary and
           digital elevation model (elevation in feet) of the northern Mississippi embayment	2
Figure 2.    Map of the northern Mississippi Embayment (NME) showing approximate distribution
           of outcrop and subcrop of the Wilcox and Claiborne group sediments (From Brahana
           and Broshears, 2001)	16
Figure 3.    Cross-section through the northern Mississippi Embayment (NME) showing the
           generalized stratigraphy (From Brahana and Broshears, 2001)	18
Figure 4.    Map of the study area showing the distribution of wells >500 ft depth used in the study.  .. 28
Figure 5.    Example of gamma ray and resistivity borehole log response in the study area	29
Figure 6.    Locations of cross-section lines A-G in the study area	31
Figure 7.    Structure contour map of the base of the Cook Mountain  Formation in the study area. ... 35
Figure 8.    Structure contour map of the base of the Kosciusko Fm./Sparta Sand/upper Memphis
           Sand in the study area	36
Figure 9.    Structure contour map of the base of the Tallahatta Fm./Cane River Fm./middle
           Memphis Sand in the study area	37
Figure 10.   Structure contour map of the base of the Meridian Sand/Carrizo Sand/lower Memphis
           Sand in the study area	38
Figure 11.   Structure contour map of the base of the Flour Island/Tuscahoma formations in the
           study area	39
Figure 12.   Structure contour map of the base of the Fort Pillow Sand/Nanafalia Fm. in the study
           area	40
Figure 13.   Stations and Analyses within surface water database	47
Figure 14.   Number of observations by county in surface water database	47
Figure 15.   Map of surface water station locations in AR	48
Figure 16.   Map of surface water station locations in Mississippi	48
Figure 17.   Map of surface water station locations in Tennessee	48
Figure 18.   Map of ground water station locations in AR	49
Figure 19.   Map of ground water station locations in Mississippi	49
Figure 20.   Map of ground water station locations in Tennessee	50
Figure 21.   Data filtered and outliers (E.N. > 5% removed)	51
Figure 22.   Well locations in the Quaternary Alluvial aquifer.	52
Figure 23.   A) Piper diagram for hydrochemical classification of water compositions in the
           Mississippi Alluvial aquifer. B) Classification of hydrochemical water types (from
           Kehew, 2001)	56
Figure 24.   Map showing distribution of hydrogeochemical water types in the Quaternary Alluvial
           aquifer, central Mississippi Embayment (county boundaries are shown)	57
Figure 25.   Map showing TDS distribution, Quaternary Alluvial aquifer, central Mississippi
           Embayment (county boundaries are shown)	57
Figure 26.   Map showing the dissolved Fe distribution, Quaternary Alluvial aquifer, central
           Mississippi Embayment (county boundaries are shown)	58
Figure 27.   Hierarchical dendrogram of the geochemical clusters for Quaternary Alluvial aquifer.	59

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Figure 28.  Component plot of the factorial analysis, Quaternary Alluvial aquifer (ph is pH, hco3
           - HC03-, ca - Ca2+, mg - Mg2+, ec - EC, tds - IDS, so(4) - S042-, na - Na+, cl - Cr, k -
           K+, mn - Mn(total) and fe - Fe(total); 1, 2 and 3 are geochemical associations)	59
Figure 29.  Well locations in the upper Claiborne aquifer within the study area	61
Figure 30.  A) Monitoring well and well group locations in Upper Claiborne aquifer.  B) Ca2+ and
           TDS data from 1939 to 1983 for monitoring well 1	61
Figure 31.  A) Piper diagram for water chemistry data from the Upper Claiborne aquifer. 	63
Figure 32.  Scatter plot of bicarbonate (HC03) versus total dissolved solids (TDS) data from the
           upper Claiborne aquifer.   	63
Figure 33.  Distribution of major water types in the Upper Claiborne aquifer.	64
Figure 34.  Contour map of total dissolved solids (TDS) in the Upper Claiborne aquifer.	64
Figure 35.  Contour map of bicarbonate (HC03) in the Upper Claiborne aquifer.	65
Figure 36.  Hierarchical dendrogram of the geochemical associations for Upper Claiborne aquifer.  .. 65
Figure 37.  Component plot of the factorial analysis Upper Claiborne aquifer (HC03 - HC03~, Ca -
           Ca2+, Mg - Mg2+, Cond -specific conductance, S04 - S042-, Na - Na+, Cl - CI-, K - K+,
           Mn - Mn(total) and Fe - Fe(total); 1, 2 and 3 are geochemical associations)	66
Figure 38.  Wilcox diagram illustrating degree of sodium and salinity hazards in the Upper
           Claiborne aquifer.	66
Figure 39.  Well locations in the Middle Claiborne aquifer within the study area	67
Figure 40.  A) Ca2+ and TDS data from 1968 to 2004 for monitoring well 1304 (Figure 41) in the
           Sparta Sand. B) Ca2+ and TDS data from 1990 to 2002 for monitoring well Sh:K-66 in
           the upper Memphis Sand	68
Figure 41.  Locations of monitoring wells in the Middle Claiborne aquifer used for time-series
           plots of water quality	68
Figure 42.  Piper diagram for water chemistry data from the Middle Claiborne aquifer. See Figure
           12B for classification fields	69
Figure 43.  Scatter plot of bicarbonate (HC03) versus total dissolved solids (TDS) data from the
           Middle Claiborne aquifer.  	70
Figure 44.  Distribution of major water types in the Middle Claiborne aquifer.  	71
Figure 45.  Potentiometric surface of the Middle Claiborne (Memphis-Sparta) aquifer in the
           Mississippi embayment (Schrader, 2008a)	72
Figure 46.  Distribution of TDS values in the Middle Claiborne aquifer.  	73
Figure 47.  Distribution of Ca values in the Middle Claiborne aquifer.  	73
Figure 48.  Hierarchical dendrogram of the geochemical clusters for the Middle Claiborne aquifer. ... 74
Figure 49.  Wilcox diagram illustrating degree of sodium and salinity hazards in the Middle
           Claiborne aquifer.	74
Figure 50.  Well locations in the Lower Claiborne-Wilcox aquifer within the study area	75
Figure 51.  A) Monitoring well group locations in Lower Claiborne-Wilcox aquifer. B) TDS data
           from 1942 to 2001 for Arkansas (Fort Pillow Sand) monitoring locations. C) TDS data
           from 1925 to 1996 for Tennessee (Fort Pillow Sand) monitoring well locations. D) TDS
           data from 1941 to 1984 for Louisiana Wilcox Formation monitoring wells	76
Figure 52.  Piper diagram for water chemistry data from the Lower Claiborne-Wilcox aquifer.	78
Figure 53.  Scatter plot of bicarbonate (HC03) versus total dissolved solids (TDS) data from the
           Lower Claiborne-Wilcox aquifer.  	79
Figure 54.  Distribution of major water types in the Lower Claiborne-Wilcox aquifer.  	79

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Figure 55.  Distribution of IDS values in the Lower Claiborne-Wilcox aquifer.	80
Figure 56.  Distribution of iron values in the Lower Claiborne-Wilcox aquifer.  	80
Figure 57.  Hierarchical dendrogram of the geochemical clusters for the Lower Claiborne-Wilcox
           aquifer.   	81
Figure 58.  Wilcox diagram illustrating degree of sodium and salinity hazards in the Lower
           Claiborne-Wilcox aquifer.	81
Figure 59.  Distribution of USGS aquifer parameter assessment scores for all geologic units	88
Figure 60.  USGS aquifer parameter records with a score of 7 or greater.	88
Figure 61.  Monitored and abandoned gaging station locations	89
Figure 62.  Bridge crossing locations investigates for geotechnical information on riverbed
           parameters	98
Figure 63.  Status of wetland digitization based on NWI metadata from the US FWS	101
Figure 64.  Discrepancy between the national and Tennessee FWS office on available digital
           wetland data	101
Figure 65.  Delineation of Middle and Lower Claiborne and Wilcox recharge areas within the
           Mississippi Embayment	104
Figure 66.  Location of evapotranspiration control towers proximal to the study area	108
Figure 67.  Land cover types present within the study area at 200 meter resolution (from MRLC
           consortium 2001 Land Cover Database)	110
Figure 68.  Depiction of contiguous areas of similar land cover type for possible implementation
           of evapotranspiration point measurement instrumentation	111

Plate 1      Section G - G'  	135
Plate 1      Section G - G' (cont.)	136
Plate 2     Section A - A'	137
Plate 3     Section B - B'	138
Plate 4     Section C - C'  	139
Plate 5     Section D-D'	140
Plate 6     Section E - E'	141
Plate 7     Section F - F'	142

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                                                                                   Tables
Table 1.    Geologic and hydrostratigraphic units correlated throughout the Mississippi
           Embayment (From Hart et al., 2008)	21
Table 2.    Geologic correlation diagram for Cenozoic strata in Mississippi (from Dockery, 1996)	22
Table 3.    Lithostratigraphy and hydrostratigraphy in the Memphis, Tennessee, area (From
           Brahana and Broshears, 2001)	24
Table 4.    Proposed lithostratigraphic correlation for the northern and central Mississippi
           Embayment (modified from Hosman and Weiss, 1991)	30
Table 5.    Surface interpolation statistics	41
Table 6.    Surface water database contents	46
Table 7.    Descriptive statistical parameters for ground water of the Quaternary Middle
           Mississippi Embayment (n.d. is non-detect)	54
Table 8.    Descriptive statistical parameters for ground water of the Upper Claiborne aquifer in
           the central and northern Mississippi embayment	62
Table 9.    Descriptive statistical parameters for ground water of the Middle Claiborne aquifer in
           the central and northern Mississippi embayment	69
Table 10.   Descriptive statistical parameters for ground water of the Lower Claiborne-Wilcox
           aquifer in the Mississippi embayment	77
Table 11.   Aquifer parameter data from  literature review	85
Table 12.   Breakdown of USGS aquifer parameter tests by county and aquifer.	87
Table 13.   Scoring matrix used to qualitatively assess the reliability of the USGS aquifer
           parameter data	87
Table 14.   Number of USGS aquifer parameter records that match the assessment criteria and
           the average score by aquifer.	88
Table 15.   Location and date of activation information for gage stations shown  in Figure 61	90
Table 16.   Gaged streams investigated for baseflow conditions	91
Table 17.   Baseflow values estimated using partial duration curves	92
Table 18.   Baseflow values estimated using PART.  	93
Table 19.   Baseflow values estimated with the WHAT model using the LMM, BFLOW and Ekhardt
           techniques	94
Table 20.   Summarization of baseflow intensities	96
Table 21.   Average baseflow intensities for MERGWS streams	97
Table 22.   Shelby and Fayette County, Tennessee bridge crossings investigated for geotechnical
           information on riverbed parameters including an estimation of riverbed conductance	99
Table 23.   List of evapotranspiration estimation methods	105
Table 24.   Comparison  of point measurement evapotranspiration methods	107
Table App1. Data ranking system for geophysical log data	143
Table App2. Numerical  ranking system for spatial location data (x,y)	143
Table App3. Ranking system for elevation data (z)	143
Table App4. Rankings of well logs including that for assessing the log,  location and elevation	144
Table App4. Rankings of well logs including that for assessing the log,  location and elevation (cont.)... 145
Table App4. Rankings of well logs including that for assessing the log,  location and elevation (cont.)... 146

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Table App4. Rankings of well logs including that for assessing the log, location and elevation (cont.).. . 147
Table App4. Rankings of well logs including that for assessing the log, location and elevation (cont.).. . 148
Table App4. Rankings of well logs including that for assessing the log, location and elevation (cont.).. . 149
Table App4. Rankings of well logs including that for assessing the log, location and elevation (cont.) . . 150
Table App4. Rankings of well logs including that for assessing the log, location and elevation (cont.) . . 151
Table App4. Rankings of well logs including that for assessing the log, location and elevation (cont.) . . 152
Table App4. Rankings of well logs including that for assessing the log, location and elevation (cont.) . . 153
Table App5. Loosahatchie/SR 14 Hydraulic Conductivity BR-18	160
Table App6. Loosahatchie/SR 14 Hydraulic Conductivity BR-19	160
Table App7. Loosahatchie/SR 14 Hydraulic Conductivity BR-20	161
Table App8. Loosahatchie/SR 14 Hydraulic Conductivity BR-23	161
Table App9. Loosahatchie/SR 14 Hydraulic Conductivity BR-24	162
Table ApplO. Wolf/ SR 3 Hydraulic Conductivity B-7	162
Table App11. Wolf/ SR 3 Hydraulic Conductivity B-8	163
Table App12. Wolf/ SR 3 Hydraulic Conductivity B-12	163
Table App13. Wolf/ SR 3 Hydraulic Conductivity B-13	164
Table App14. Wolf/ Walnut Grove Hydraulic Conductivity BB-23	164
Table App15. Wolf/ Walnut Grove Hydraulic Conductivity BB-26	165
Table App16. Wolf/ Walnut Grove Hydraulic Conductivity BB-29	165
Table App17. Nonconnah/Near Riverport Hydraulic Conductivity B-1	166
Table App18. Nonconnah/Near Riverport Hydraulic Conductivity B-2	166
Table App19. Nonconnah/Near Riverport Hydraulic Conductivity B-12	167
Table App20. Nonconnah/Airways Blvd Hydraulic Conductivity B-1	167
Table App21. Nonconnah/Airways Blvd Hydraulic Conductivity B-2	168
Table App22. Nonconnah/Knight Arnold Hydraulic Conductivity B-6	168
Table App23. Nonconnah/Knight Arnold Hydraulic Conductivity B-7	169
Table App24. Nonconnah/Knight Arnold Hydraulic Conductivity B-8	169
Table App25. Wolf/ SR 194 Hydraulic Conductivity B-1 	170
Table App26. Wolf/ SR 194 Hydraulic Conductivity B-2	171
Table App27. Wolf/SR 57 Hydraulic Conductivity B-1	171
Table App28. Wolf/SR 57 Hydraulic Conductivity B-2	172
Table App29. Wolf/SR 57 Hydraulic Conductivity B-3	172
Table AppSO. Wolf/McKinstry Hydraulic Conductivity B-1	173
Table App31. Wolf/McKinstry Hydraulic Conductivity B-2	173
Table App32. Wolf/SR 76 Hydraulic Conductivity B-1	174
Table App33. Wolf/SR 76 Hydraulic Conductivity B-2	174

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                                                                                     1.0
                                                                          introduction
Increased water usage in the southeastern
United       in the tri-state      of Tennessee,
Mississippi and Arkansas poses a dilemma to
ensuring long-term sustainability of the quantity
and quality of ground-water resources that
underlie the region. Demand for ground water
by agriculture,  municipalities and industry is
presently stressing the sustainable yield of the
fresh water aquifers.  Instances of ground-water
contamination  have closed water-treatment
facilities; many other potential contaminant
sources could threaten human health. To
address these threats, federal, state and
local government have initiated a four-phase
research effort to understand, model, and
suggest best management practices for the
ground-water resources in the region.

Phase I  will develop the intellectual, organi-
zational, and methodological foundation for
the subsequent three phases.  During Phase
I, the various stores of hydrogeologic
will be evaluated on their quality and usability
to addressing the impact of the surmount-
ing        on the regional ground-water
system.  The      under investigation includes
the Tennessee counties of Shelby, Fayette,
Hardeman, and Tipton, the Mississippi coun-
ties of Desoto, Marshall and Tunica, and the
Arkansas county of Crittenden (Figure 1).
Standardized and  innovative methodologies
and technologies will  be  employed in Phase II
to fill the          identified in Phase I. This
    gathering will be conducted in such a way
as to couple the spatial and temporal compo-
nents of the hydrologic cycle of atmospheric
charging, land surface processes and ground
water. In this way, the fluxes and stores can
be better represented holistically; an approach
not adopted in previous studies thus to their
detriment. Guiding the     collection in Phase
II and the predictive, analytical and conceptual
models constructed during Phase III are the
science  questions posed by the local stake-
holders. These questions are:
 1. Can the regional ground-water
    resources meet the future demands by
    municipalities, industry and agriculture?
    If not, what are the expected ground-
    water shortages and where are they
    occurring?

 2. What are those factors in the regional
    ground-water system that impact
    sustainable yield and water quality?

 3. Is the Mississippi River a viable
    alternative water source  for agricultural
    usage?

 4. What impact would increased
    agricultural pumping from the Memphis/
    Sparta aquifer have on the quantity and
    quality of ground water necessary to
    meet the demands by municipalities and
    industry?

 5. To what extent are ground-water
    withdrawals impacting ecosystems?

Answers to these questions will guide policy
makers  in  Phase IV to make  the  necessary
changes to land use practices and water
consumption that, cumulatively over time,
will negatively  impact the sustainability of the
region's ground water as a viable water source.

In 2006, Congress appropriated Phase I dollars
within EPA for  the study.  Phase I specifically
addresses EPA's mission of protecting human
health and the environment by (1) conduct-
ing an assessment of     stores existing at
the     and local level, (2) evaluating
      at the regional      that will sharpen
our understanding of the regional ground-water
system and its connection to  other environmen-
tal processes,  and (3) organizing      collec-
tion practices on a regional scale that will assist
with addressing ground-water resources in a
holistic manner. The inherent benefit of this
phase is an improved ability to better address
issues that threaten regional  ground water

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              92°0'0"W
90°0'0"W
                                           88°0'0"W
                                      aigbfeid  Mississippi . **"
                                             eĢ_    MERGWS
                                             ^        I
                                                                            Itawar^ba
                                                                              1
                                                                                          -36°0'0"N
  34°0'0"N-
                                                     -34°0'0"N
              92°0'0"W
               ^       I
                30     60
 I
120 Miles
90°0'0"W                          88°0'0"W
         Legend
         |      Major rivers
         |     | Geologic investigative extent
         |     | Crowley's Ridge
              J Northern Mississippi embayment
         |     | County
         	State
         Topography (USGS 30m)
         Elevation (MSL)
               High : 2,250
                                                              Low : 50
Figure 1.    MERGWS study area (counties in opaque white), geologic investigative boundary and digital
            elevation model (elevation in feet) of the northern Mississippi embayment.

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resources and ecosystems that depend on
      water resources.

In 2000, the local stakeholder community (local,
     and federal agencies and academia from
Tennessee, Arkansas and Mississippi) formed
an informal organization called MAT-RAS, or
Mississippi-Arkansas-Tennessee Regional
Aquifer Study.  This group of stakeholders met
annually to discuss the  growing threats to the
regional ground-water supply and postulate
actions to avert further degradation to the
system. A persistent problem in the     had
been the use of disparate methods and the
uncoordinated timing of hydrologic and geologic
    collection across      lines, thus creat-
ing a disjoint in the regional understanding of
aquifer systems, ground-water migration and
usage, and potential contamination threats on
water resources. Similarly, a communication
      existed between the       with regard
to ground-water resource planning. By imple-
menting a collaborative, regional approach to
improve our understanding of the ground-water
resources - without the constraint  of political
boundaries and disjointed         - the stake-
holders could begin to proactively work toward
a common goal of ensuring future  ground-water
availability without sacrificing the integrity of our
water resources. MAT-RAS never formalized
into a governing body and eventually stopped
meeting, yet the desire  of the local stakehold-
ers to do something remained.  Phase 1 of this
effort  included the formation of a Scientific
Advisory Committee (SAC) comprised of the
same local stakeholders under MAT-RAS who
would oversee the effort.

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                                                                                    2.0
                                                                        Background
The Mid-South region, which includes the
tri-state     of Mississippi, Arkansas and
Tennessee, is fortunate to have an abundance
of fresh water.  These water resources include
surface water, such the Mississippi River,
and ground water. However,  because of its
generally high quality and relative      of
access, our most valuable water resource is
ground water. The ground water resources
of the region stem from the formation of the
Mississippi Embayment, a geologic extension
of the Gulf Coastal Plain province that extends
into the mid-section of the United
and terminates at the southern tip of Illinois
(Gushing et al., 1964). The ground water
consumed within the embayment accounts for
nearly 17% of that withdrawn nationally from
unconsolidated sand and gravel aquifers, with
90% of this withdrawal coming from Tennessee,
Arkansas and Mississippi (Hutson, 1998).
Farmers rely heavily upon the quantity of
ground water for the irrigation of their crops and
water for their livestock. In Eastern Arkansas,
ground water consumption for irrigation,
primarily for rice crops, is approximately 6500
billion gallons per day  (bgd), averaged on an
annual scale. Similarly, 1300 bgd is withdrawn
in Mississippi for irrigation.  Within the embay-
ment, Tennessee's reliance on irrigation use is
much less at 3 million  gallons per day (mgd);
however,  ground water usage for public supply
and industry is highest among the three
at 258 and 50 mgd, respectively (Hutson,
1998). A majority of the ground water con-
sumed in Tennessee occurs in Shelby County,
which is home to Memphis, ranked 17th in over-
all population among major cities nationwide
(Census 2000).  In Memphis, Tennessee alone,
over 80 industries have located there primar-
ily because of the ground-water quantity and
quality;      industries combine to return over
a billion dollars per year back into the nation's
economy.
 * Issue: Approximately 90% of ground-water
   withdrawal in Eastern Arkansas is for
   agricultural purposes, primarily rice produc-
   tion. A daily average of 6.4 billion gallons
   per day of ground water is pumped from the
   Mississippi River alluvial aquifer (Maupin
   and Barber, 2005); however, this pumping
   occurs mostly during the growing season.
   Declines in the Mississippi River alluvial
   aquifer and concerns about aquifer consoli-
   dation have prompted farmers to consider
   tapping the deeper Memphis/Sparta aquifer
   for irrigation water. Overuse is the major
   threat in Arkansas.

Water levels within the Mississippi  River alluvial
aquifer in Eastern Arkansas have been on a
continual decline in the high production
such as Poinsett and Lonoke counties, drop-
ping as much as 20  to 25 ft (Westerfield, 1990).
Seven identifiable cones of depression have
formed in twelve of the twenty-three counties
in Eastern Arkansas, and long-term water-level
recording in some of these depressions will
determine their persistence (Schrader, 2001).
Similar to other counties in Eastern Arkansas,
alluvial water levels in  Crittenden County are
lowest in the fall after the growing season,
then rebound to some degree by spring after
the winter rains (Plafcan, 1985; Plafcan,  1986;
Westerfield, 1989; Westerfield, 1990).

Between 1967 and 1986, alluvial water levels
in Crittenden County remained  relatively level,
fluctuating between 200 and 203 ft mean
level (MSL). Since 1987 water  levels have
dropped with the most rapid decline occur-
ring after      to about 192 ft MSL. North
of Crittenden County in Mississippi County,
water levels have fluctuated since 1955, but a
sustained decline is  not apparent (Ackerman,
1989).  St. Francis and Lee counties south
of Crittenden have seen water-level declines
in the alluvial aquifer with St. Francis County
showing a dramatic decline between 1988 and

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2001 of nearly 12 ft (Schrader, 2001). The
absence of dramatic drops in the alluvial water
     in those Arkansas counties bordering the
Mississippi River is attributed to the hydraulic
connection between the alluvial aquifer and the
river. A pressure transducer in the Crittenden
County well, AR:H-2A, and operated by the
University of Memphis has indicated an imme-
     response in the alluvial water level as the
Mississippi River      rises and falls.

In the Sparta (Memphis) aquifer, production has
been focused in central and southern Eastern
Arkansas. Since 1975, withdrawals from
the Sparta aquifer have doubled (Hays and
Fugitt,  1999). Persistent cones of depression
exist at major withdrawal centers in Jefferson,
Columbia  and Union counties (Edds and
Fitzpatrick, 1984; Edds and Fitzpatrick, 1986;
Westerfield, 1995; Joseph, 1998). In Columbia
and Union counties, the Sparta, originally
confined, has since become unconfined with
water level dropping below the formation top
(Hays and Fugitt, 1999).  From 1983 to 1993,
as many as three wells tightly       within the
Sparta aquifer within Crittenden County were
used for control in developing the potentiomet-
ric maps.  In 2000,  the number of Sparta wells
in Crittenden County increased to four (Joseph,
2000).  Sparta water levels remained near
consistent from  1983 to 2000.  In the counties
surrounding Crittenden, production from the
Sparta increased from 1995 to 2000 with a
cone of depression apparent in Poinsett County
northwest of Crittenden and growing southward
to include Cross County just west of Crittenden
(Joseph, 2000). The general trend of the gradi-
ent in the Sparta across Crittenden  County is
toward the southwest. A recent, yet unpub-
lished potentiometric map of the Sparta aquifer
conducted by the USGS Tennessee Water
Science Center was developed that included
water level measurements taken in Tennessee,
Mississippi and  Arkansas.  The suggested gra-
dient trend across Crittenden County was again
to the southwest (communication, Michael
Bradley USGS TN Water Science Center).

Water use information for  the deeper Wilcox
group is very limited.  Withdrawal from this
aquifer is primarily for municipal or industrial
use. The depth of the unit limits its use for
irrigation, especially when water from the
Mississippi River alluvial aquifer is readily avail-
able.  In Crittenden County, approximately 7.85
million gallons on average each day (MOD)
is withdrawn,  primarily by West Memphis for
drinking water (Holland, 1999). In Mississippi
County to the north, 22.3 MGD is withdrawn.
Little (<4 MGD) to no water is taken from the
Wilcox group  in the remaining adjacent coun-
ties to Crittenden. Not enough information is
available to        water-use trends in the
Wilcox.

             dilemma
 Ŧ   Issue: Nearly 65% of ground water with-
    drawn in Mississippi within the Mississippi
    Embayment region is for irrigation pur-
    poses, primarily rice production. Pumping
    from the Mississippi River alluvial and
    Sparta aquifers is prevalent Development
    growth in Desoto County  directly south of
    Memphis,  Tennessee has made Desoto
    County the       growing county in
    Mississippi for the last 10 years and is
    projected  to rank highest  in future years.
    Overuse and municipal demands are the
           concerns in Mississippi.

In Mississippi, the Mississippi River alluvial
aquifer is present only within  the northwestern
section of the      bordered to the     by
the Bluff Hills.  The general alluvial water-level
trend  is to the south (Goldsmith, 1993). Water
levels fluctuate in Desoto and Tunica counties
between spring and fall. Declines, some as
much as 5 ft,  occur across these counties with
few exceptions in the fall after the growing
season, and then rebound as much as 6 ft by
spring after the winter rains (Darden, 1983;
Sumner, 1984; Goldsmith, 1993).  Water levels
within the interior of Tunica County did maintain
a decline between 1981 and  1983. Overall,
water levels have declined on average less than
0.2 ft  per year since 1980 (Arthur, 2001). The
largest cones of depression occur in the central
and southern  portion of the alluvial aquifer in
Sunflower, Humphreys and Washington coun-
ties where the depth of water, usually 25 ft
below ground surface, is commonly 30 to 50 ft

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(Sumner and Wasson, 1990; O'Hara and Reed,
1995).  Though withdrawal from the Mississippi
River alluvial aquifer is large, recharge from
precipitation and the rivers has sustained levels
and storage still remains at 96 to 99 percent of
the aquifer's unconfined capacity (Arthur, 2001).
Sumner and Wasson (1990) simulated an
increase in pumping from 1983 to 2003 assum-
ing pumpage was  1900 million gallons per day
(MOD).  Assuming pumpage was distributed
uniformly, drawdown in Tunica County was esti-
mated to       10 ft. Estimated ground-water
consumption for the Mississippi River alluvial
aquifer in 2000 was 6,410 MOD (Maupin and
Barber, 2005).

The Sparta aquifer in northwestern Mississippi
has major cones of depression that are further
south of the alluvial aquifer water-level depres-
sions, occurring in Sharkey, Yazoo and Hinds
counties. Smaller cones of depression in the
Sparta also exist further north in Sunflower,
Bolivar and Coahoma counties.  Again,
Coahoma  County  is south of Tunica adjacent
to the Mississippi River. Potentiometric water
levels in 1984 indicate a west-northwest
gradient across  Desoto County, and then
southwestward through Tunica County (Darden,
1987).  Darden (1987) did not show any
Sparta observation wells in Marshall County.
Arthur and Taylor (1990) indicated that under
predevelopment conditions, gradients in the
Sparta aquifer were directly toward the west
then southwest. Brahana and Broshears
(2001) also suggested a western gradient
pattern in the Sparta aquifer within Desoto
County.  Similar to Darden (1987), Oakley and
Burt (1994) observed a northwest gradient
across Desoto County toward Shelby County.
The northwest gradient was still prevalent in
Bradley's unpublished contour map of water
levels in the Memphis/Sparta aquifer across
the tri-state region. Between 1980 and 1989,
water levels in the Sparta aquifer in Desoto
County have dropped as much as 16 ft (Oakley
and Burt, 1994). Observations in Marshall  and
Desoto were not available.  South of Tunica in
Coahoma  County,  water levels have declined
as much as 12 ft.
Ground-water production from the Lower
Wilcox aquifer in Mississippi is primarily used
for municipal and industrial purposes. Water
levels across Marshall and Desoto counties
were approximated by Oakley et al. (1994),
however greater well control in Tunica County
and the adjoining Tate and Panola counties
allowed for more assured contouring. Some
of the largest water level declines in the Wilcox
aquifer occurred in Tunica County, decreasing
20 ft between 1979 and 1988 (Oakley et al.,
1994). A cone of depression in Panola County
has forced the gradient in Tunica toward the
southeast.

Population growth in Mississippi has
on the increase since 1990. Only two of
Mississippi's 82 counties had a negative
percent population change during this time
period. Desoto  County had the largest per-
cent population  change  at 66.7%. The next
lowest percent change was Rankin County at
41.4%. Marshall and Tunica counties had an
increase of 20.6% and 25.2%, respectively,
over the same time period. Desoto County is
projected to remain the        growing county
in Mississippi between 2004 and 2009. There
are no metro-sized cities in Desoto, Marshall
or Tunica counties. Desoto County is directly
south of Memphis, Tennessee. Data is courtesy
of the Memphis Chamber of Commerce (2005).


 • issue: Shelby County is second in the
   nation in regard to sole dependence
   on ground water for municipal use.
    Withdrawals in Shelby County have caused
   a major cone of depression and reori-
   entation of aquifer gradients in
   counties. Growth of Memphis and other
   municipalities has heightened the concern
   for urban sprawl impacts to the recharge
   area.  In addition to urban sprawl and
   sustainabiiity of available water in light of
   adjacent       threats, aquitard breaches
   are posing an  increasing contamination
   threat.

The total  fresh ground water withdrawal on
average for the State of Tennessee is approxi-
mately 275 MGD.  Ground-water withdrawal in

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Shelby County, Tennessee accounts for nearly
80% of the total for the state. Therefore, focus
on the ground-water system in west Tennessee
has been on water use in Shelby County. The
Quaternary aquifer in west Tennessee is a
remnant of a high level terrace of an ances-
tral Ohio/Mississippi river system (Austin et
al., 1991). Withdrawal from the Quaternary
aquifer is minimal, primarily used for irrigation
and domestic use.  Parks (1990) developed a
water table map for Shelby County       on
water levels in 1987.  This is the sole survey;
however,  the University of Memphis is revisiting
the water table mapping  presently.  In the fall of
1987, the water table mimicked the topography
of the land surface with discharge typically
to the local river systems. Five localized
depressions in the water     were resolved
as      where  the Upper Claiborne confining
unit,  separating the Quaternary aquifer from
the Memphis aquifer, was thin or absent, thus
allowing for downward vertical leakage (Parks,
1990).

Exploitation of the ground-water resources of
the Memphis aquifer beneath Shelby County
began in the late 1880's. The predevelopment
gradient of the Memphis  aquifer underneath
Shelby County was to the west-northwest
(Brahana and Broshears, 2001). In 1995,
ground-water gradients are toward  the major
cone of depression beneath  downtown
Memphis - the origination of the earliest
pumping (Kingsbury, 1996).  In close proximity
to the Shelby County border, Memphis aqui-
fer gradients in Desoto County,  Mississippi,
Crittenden County,  Arkansas and Tipton
County, Tennessee are toward Shelby County.
Since pumping began from the  Memphis
aquifer, water levels have dropped nearly 125
ft, however the aquifer remains confined.  In
northeast Shelby County, just      of the
Memphis aquifer outcrop region and within
the recharge area, water levels  observed in
the observation well Fa:R-2 have remained
steady since 1950 (Kingsbury, 1996).  Memphis
aquifer water levels at the county-wide
have not      recorded for Tipton,  Fayette and
Hardeman counties. A review by the University
of Memphis of measured static water levels
by drillers on private wells in Fayette County
indicated that the Memphis aquifer water
(Fayette is the recharge     for the Memphis
aquifer) mimicked land surface topography with
flow toward the alluvial valleys.

The Lower Wilcox, or Fort Pillow aquifer, has
limited withdrawal as compared to the Memphis
aquifer above it. Across Shelby County gradi-
ents are to the southwest toward a major cone
of depression beneath West Memphis across
the Mississippi River in Crittenden County,
Arkansas (Kingsbury, 1996). Smaller, localized
water-level depressions in the Fort Pillow aqui-
fer exist in Desoto County, Arkansas and under
the City of Millington and below the Shaw
wellfield in Shelby County (Kingsbury, 1996).
At the same location as Fa:R-2, observation
well Fa:R-1 has indicated a near 25 ft decline in
the Fort Pillow aquifer between  1950 and 1995.

The Memphis aquifer is the primary water
source for municipalities and industry.
Replenishment of this vital resource occurs
over a 2800 mi2     across West Tennessee.
Upgradient of the depression beneath
Memphis, Tennessee, the recharge      begins
along the eastern border of Shelby County
and continues eastward across  Fayette County
and into Hardeman County.  Growth in Shelby
County has caused urban development to
move into the recharge     at an astonish-
ing  rate. Increased risk of contamination and
an encumbrance to recharge of the Memphis
aquifer resulting from urban sprawl has raised
considerable concern regarding the sustain-
ability of Memphis aquifer water quality and
quantity.  In the southeastern corner of Shelby
County within the Memphis aquifer outcrop
area, one of the Town of Collierville's major
water treatment facilities was impacted by two
        industrial contaminant plumes result-
ing  in inoperability of the plant and a near $1
million economic loss (communication, Tim
Overly, Town of Collierville).

The Upper Claiborne confining clay overlays
much of the Memphis aquifer in Shelby County;
however, localized breaches in the clay pro-
vide avenues for inter-aquifer exchange of
water with the unconfined Quaternary aquifer
(Graham and Parks, 1986; Parks 1990).  The

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Quaternary aquifer is more prone to contamina-
tion from     such as the Bellevue, Hollywood,
Brooks,  and Jackson Pit waste-disposal dumps
(Parks et al,, 1981), the Shelby County landfill
(Bradley, 1991; Parks and Mirecki, 1992),
Memphis Defense Depot (Miller et al., 1994),
Mississippi  River influence (Brown, 1993;
Parks et al., 1995), nearly 1600 underground
storage  tanks (query Tennessee Department
of Environment and Conservation  UST pro-
gram), and  the petroleum industry.  Due to the
extensive pumping from the Memphis aquifer
in Shelby County, water levels in the Memphis
aquifer have fallen below that of the Quaternary
aquifer inducing downward  vertical
through  the confining unit breaches into the
Memphis aquifer (Parks, 1990; Brahana and
Broshears,  2001; Larsen  et al., 2003).

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                                                                                   3.0
                                                                Project Task Plan
The work plan for Phase I is subdivided into
five main topics.  These topics are further
divided into subtopics as follows:

 1. Perform geologic mapping of the region

    Ŧ  Combine with the University of Memphis
       geologic borehole          acquired
       geophysical logs from Tennessee,
       Mississippi and Arkansas

    •  Correlate  interpreted geologic picks
       from the geophysical logs to create
       cross-sections of formational boundar-
       ies and significant intra-bedding

    •  Construct quasi-3D representation of
       regional litho-stratigraphy and
       regions of insufficient data

 2. Ascertain water quality changes and
    ground-water contamination threats

    •  Catalog water chemistry variables from
       disparate

    ŧ  Ascertain  temporal water quality
       changes and chart statistical variation
       among measurement geochemical
       variables

    •  Conduct a spatial assessment of
       contamination threats to the ground
       water and ascertain chemical signatures
       and environmental tracers valuable for
       numerical model calibration and analyti-
       cal modeling
3.  Conduct assessment on aquifer
   parameter values and measurement
   methodologies

   • Acquire relevant literature of
     investigations into aquifer parameter
     information

   • Construct aquifer parameter
     from historic USGS records

   • Determine the appropriateness of
     measurement value as a spatially aerial
     and vertically relevant estimate

4.  Catalog surface water sources to
   ground water

   • Compile information on surface water
     sources to ground water and evaluate
     the significance of the sources

   ŧ Form prognosis on lacking surface
     water property data

5.  Diagnose additional sources/sinks of
   water to the ground-water system

   • Ascertain  estimation methodologies for
     ground-water recharge

   Ŧ Evaluate methods for estimating
     evapotranspiration

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                                                                                    4.0
                              Quality Assurance  Project  Plan  (QAPP)
                                                               Quality  Assurance
The final QAPP for this project     accepted
on August 20, 2008. Quality assurance visits
were accomplished while researchers were
actively acquiring and incorporating     for
the described tasks. Reports to the primary
investigator were completed from these visits
and included accomplishments  made on each
task and descriptions of points of concern.
Subsequent quality assurance visits included
determination of fulfillment of these points to
ensure     quality.  Data backup and elec-
tronic records of     input and interpretation
were the primary points of concern during
these visits and deficiencies were satisfied
readily.  A summary of the      quality assur-
     for the project is described below, catego-
rized by the five main topics as  outlined above.

Task 1: Perform geologic mapping of the
region.

Data transcription - to assure the accuracy of
    transcription of secondary      sources,
the quality assurance of this     transfer
included check-print and/or two-person
entry.  Signatures (including electronic) were
required in the     acquisition  of     entry
verification form signifying completeness and
correctness of the     entry. The  record of
authentication for               became part
of the     file repository denoting  verification,
completeness, and correctness of the
entry.

Data quality - was           using the follow-
ing parameters:

 • Presence of multiple geophysical logs
   for the same borehole, consistency and
   technological reliability of logging instru-
   mentation and protocol, and the presence
   of a corresponding geologist's or driller's log
   was required.
 •  Geologist logs used to        fine inter-
   bedding of sediments and geologic correla-
   tion were completed by matching digitized
   log patterns, representing geologic forma-
   tions or members among spatially distant
   boreholes.

 Ŧ  Quality assessment of such      included
   consistency of formations over the region
   or average thickness of geological forma-
   tions, evidence for uplift or subsidence of
   the top or bottom of formations in multiple
   correlated sections,  seismic cross-sections,
   and regionally interpolated surfaces were
   used to       the presence of fault offsets
   of the sedimentary package.

 •  At least two scientists reviewed stratigraphic
   correlation and fault displacement of strata.

 Ŧ  If final interpretation of these scientists
   did not correlate, a third opinion was
   solicited for the final assurance of quality
   interpretation.

Spatial     quality - was          accord-
ing to the reliability of the source      with a
numerical ranking      for coordinates and
recorded within the metadata as described in
the QAPP.

Task 2: Ascertain water quality changes and
ground-water contamination threats.

All datasets were converted to SI units and
outliers were identified utilizing Dixon's and
Grubbs outlier tests.  Investigators also
screened for codependent      to eliminate
cross correlation of variables used in models.
Data were       across time and      for
normality.  A 95%  confidence level was set for
all statistical tests, resulting in a statistically and
chemically robust threat model allowing easy
integration of future additional data.

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Task 3:  Conduct assessment on aquifer param-
    values and measurement methodologies.

Data source and location information was
incorporated into a Microsoft EXCEL spread-
sheet and     quality was ranked for
ment as described in the QAPP and included:
published/approved;  presence of multiple or
observational wells; test duration; supporting
information; statistical and          analyses;
drawdown and recovery analyses.

Task 4:  Catalog surface water sources to
ground water.

The compilation of existing     for Task 4
incorporated the quality assessment as
described for GIS          (spatial data)
in Task 1.  Observations from peer reviewed
literature were included if determined fit
by the Project Manager, QA Manager and
Co-managers.

Task 5:  Diagnose additional sources/sinks of
water to the ground-water system.

Project information was catalogued in Microsoft
Word or Excel on the investigator's PC, backed
up on         dedicated storage (i.e.  external
hard drive) with final compilation housed at the
University of Memphis Ground Water Institute.

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                                                                                       5.0
                                                                                  Results
                             of the
A hydrostratigraphic analysis of an aquifer
system aims to identify the extent and hydro-
logic characteristics of water-bearing rocks
and sediments in an aquifer system.  Although
the hydrostratigraphy of tertiary aquifers in the
Mississippi Embayment (ME) has been evalu-
     on regional (Boswell et al., 1968, Gushing
et al., 1964; Hosman et al., 1968; Gushing et
al., 1970; Hosman  and Weiss,  1991),      and
local (Crineret al.,  1964; Payne, 1968; 1973;
1975; Parks and Carmichaei, 1989; 1990a;
1990b; Brahana and Broshears, 2001) scales,
a hydrostratigraphic analysis at a subre-
gional scale in the  tri-state region of northern
Mississippi, eastern Arkansas,  and western
Tennessee is         to address stratigraphic
problems and water resource sustainability.
         lithostratigraphic  nomenclature and
aquifer conceptualization differ among states,
careful stratigraphic correlation and detailed
aquifer assessment are needed to ensure
consistency in hydrogeologic modeling.  In
addition, hydrostratigraphic subdivisions of
aquifers and confining units may be necessary
to       water resources at the subregional
scale.

The objectives of this  section are outlined as
follows:

 • Acquire geologic, stratigraphic, and geo-
   physical     in the region that will enable
   development of a detailed sub-regional
   model of the major drinking-water aquifers
   in the region: Memphis and Fort  Pillow
   aquifers.

 Ŧ Assess the extent, physical characteristics,
   and  connectivity of the Memphis and Fort
   Pillow aquifers, as well as their relation-
   ship to other regional aquifers, such as
   the Mississippi  Alluvial and shallow fluvial/
   alluvial aquifers, and intervening confining
   units.
 * Assess the quality of existing hydrostrati-
   graphic      and quantitatively
   where the existing      are insufficient in
   extent or quality to accurately model the
   aquifer system

These objectives have been addressed by
acquiring geologic and geophysical      from
     and U.S. Geological Survey offices as
well as private      sources and compiling the
results into a master           The geophysi-
cal log data, which are the primary sources
of stratigraphic information, were evaluated
for their quality of log signal, accuracy of well
location and number of correlative, useful log
plots. Data meeting the quality thresholds were
used to evaluate downhole lithologic varia-
tions in      borehole. Existing stratigraphic
reports and publications were used to correlate
lithology to geologic formations and hydro-
stratigraphic units (aquifers and confining units)
and interpret the stratigraphic and structural
relationships. The geologic formations were
then correlated between individual boreholes
to produce regional  cross-sections. These
regional cross-sections were used to evaluate
not only stratigraphic variations in the units but
also  lithologic variations within the units and
probable faults that displace the strata. The
     of this process was not to develop new
stratigraphic units, but rather to merge strati-
graphic and structural concepts across
boundaries, where different nomenclature and
definitions are applied.  Quality of the geo-
physical log     was quantified by ranking the
     according to Table App1 (see Appendix
Geophysical Logs) from the Project QAPP.
Logs were deemed acceptable with a rank of
The refined stratigraphic cross-sections were
then used to interpret well logs that exist
between the section lines to improve
coverage across the study area.  Following
this process, contour surfaces of the strati-
graphic bases of formations were created.

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The interpolation process involves achieving a
best-fit curve between data points to produce
the surface. The residual from the best-fit
process is used as an indicator of the accu-
racy of the stratigraphic model.  Areas of high
residual (high error) are considered  areas that
require further study to accurately depict the
stratigraphic and structural complexities of the
associated aquifer systems.

The results of both the cross-section and
surface-map studies provide the framework
for guiding hydrostratigraphic and hydrologic
investigations in subsequent project phases.

Geophysical Log Analysis
Geophysical log analysis  involved a review of
published literature on Tertiary stratigraphy and
hydrostratigraphy of the Mississippi  Embayment
(ME) region (Figure 1), as well as pertinent
studies of correlative Gulf Coast strata.  The
review of the regional stratigraphy allowed
                                         nomenclature across the three states to be
                                         correlated and problems identified. A prelimi-
                                         nary Tertiary stratigraphic correlation chart was
                                         developed and subsequently applied to the
                                         interpretation of geophysical  log data.

                                         Previous studies have shown that the
                                         stratigraphic character of the Claiborne and
                                         Wilcox groups changes  at approximately the
                                         Tennessee-Mississippi state  line (Figure 2),
                                         which has caused past  problems in correla-
                                         tion (Moore, 1965) and  assessment of water
                                         resources (Hosman and Weiss, 1991; Brahana
                                         and Broshears, 2001).  In this study, the Fort
                                         Pillow Sand,  Flour Island, Memphis Sand,
                                         Cook Mountain, and Cockfield formations as
                                         defined in Moore  (1965), Hosman et al. (1968),
                                         Moore  and Brown (1969), Fredericksen et al.
                                         (1982), and Hosman (1996) are mapped in
                                         Tennessee and in adjacent regions of Arkansas
                                         and Mississippi.  Correlative  Paleocene and
                                         Eocene geologic  units (Gushing et al., 1964;
       E~3
    EXPLANATION

APPROXIMATE AREA OF OUTCROP
 OF WILCOX GROUP, INCLUDING
 FORT PILLOW SAND AND
 EQUIVALENTS

APPROXIMATE AREA WHERE OUTCROP
 OP WILCOX GROUP IS COVERED BY
 SATURATED ALLUVIUM

APPROXIMATE AREA OP OUTCROP OF
 CLAtBORNE GROUP. INCLUDING
 MEMPHIS SAND AND EQUIVALENTS

APPROXIMATE AREA WHERE OUTCROP
 OP CLAIBORNE GROUP IS COVERED BY
 SATURATED ALLUVIUM

ZONE OP TRANSITION WHERE MIDDLE
 PART OF MEMPHIS SAND CHANGES
 FROM CLAY (SOUTH) TO SAND (NORTH)

  0          Ŧ0 MILES
                   Ŧ KILOMETERS
                                                                                     ALABAMA
Figure 2.     Map of the northern Mississippi Embayment (NME) showing approximate distribution of outcrop
             and subcrop of the Wilcox and Claiborne group sediments (From Brahana and Broshears, 2001).
             Dashed line shows trace of cross-section shown in Figure 3.

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Mancini and Tew, 1991; Dockery, 1996;
McFarland, 2004) were mapped in Mississippi
and Arkansas where they are well-defined. In
general, the stratigraphic nomenclature used in
each of the       is used where clear division
of geologic formations can be made.

We obtained high-quality geophysical logs from
the various log libraries, digitized and scaled
the log information, and correlated the known
Paleocene- through Holocene-age geologic
units within the region. The primary data for
this effort exist as paper geophysical and geo-
logic logs obtained  during drilling of most water
wells and all petroleum exploration wells. Other
sources of      (geologic logs,  geologic maps,
seismic lines, etc.) were used to augment the
geophysical log     where available. However,
identification of stratigraphic units from geologic
logs, unless accompanied by detailed biostrati-
graphic     or correlative geophysical data, is
commonly ambiguous. Geologic units defined
in mapping (e.g., Russell and Parks, 1975;
Thompson, 2003a,  b, c, and d)  are difficult to
reconcile with downdip subsurface expressions
of stratigraphic units observed on geophysical
logs. Thus, geologic map      are used to
constrain the distribution of stratigraphic units
only in outcrop areas.  Seismic      are limited
in the region and generally do not provide
sufficient detail to define individual stratigraphic
units within the shallow Tertiary section.

Geophysical logs were obtained from several
sources, including the University of Memphis
Ground Water Institute (GWI), USGS offices,
     Geology offices, and private companies.
The GWI houses an extensive log library for
western Tennessee and a voluminous explora-
tion geophysical log        obtained by North
American Coal Company. In addition, geo-
physical and geologic logs were obtained from
the Mississippi Department of Environmental
Quality, Arkansas Soil and Water Conservation
Commission, and USGS offices in  Little  Rock
and Nashville.  The logs utilized by the USGS
MERAS study (Hart et al., 2008; Hart and
Clark, 2008) in Tennessee and  Arkansas were
incorporated into our database; however, some
of the logs from northern Mississippi were
not available at the time of our analysis.  In
addition, a limited set of industry logs was
obtained through the Nashville USGS office
(Carmichael, pers. comm., 2007).

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Geologic correlation and construction of
cross-sections
The lithological variation in the Paleocene
through Holocene-age geologic units in the
northern Mississippi Embayment is generally
limited to various clastic sediments and coal
(Gushing et al., 1964). The geophysical log
interpretation of these sediments is generally
straightforward; however, finely interbedded fine
sand, silt and clay are difficult to differentiate.
Geologic correlation is completed by matching
digitized log patterns,  representing geologic
formations or members, among spatially distant
boreholes. Initial studies indicate that log
patterns for several of the  geologic formations
are not consistent over the region (Owen and
Larsen, 2005; Martin,  2008). In this case,
marker horizons, such as the Zilpha Shale
interval, were used where  present to correlate
formations. If no marker horizons are evident
in the log, then average thicknesses of geologic
formations were used to approximate correla-
tions. Observation of evidence for uplift or
subsidence of the tops or bottoms of formations
in multiple correlated sections was used, along
with other information (seismic cross-sections,
regionally interpolated surfaces, etc.), to assess
the presence of fault offsets of the sedimen-
tary package.  Interpreted faults through the
sedimentary package were compared to those
identified in regional studies of faulting in the
Mississippi Embayment (Ervin and McGinnis,
1975; Thomas, 1991; Schweig and Van
Arsdale, 1996; Cox et al., 2001; Parrish and
Van Arsdale, 2004; Cox et al., 2006; Csontos et
al., 2008).

A principle objective of the first phase of the
project is to use the available data to construct
detailed litho-  and  hydro-stratigraphic models
of the study area and thus determine where
existing data are insufficient to constrain
the hydrostratigraphic model. In an effort to
address this objective, structure contour maps
of the stratigraphic units were prepared. These
surface maps  are a precursor to construction
of quasi-three-dimensional litho- and hydro-
stratigraphic models. The principle data used
to construct the surfaces is the base elevations
of stratigraphic units, which are obtained from
the interpreted geophysical logs and cross-sec-
tions. The structure contour surfaces were con-
structed using the  inverse-distance-weighted
                                            NW
                    NW
Figure 3.    Cross-section through the northern Mississippi Embayment (NME) showing the generalized stra-
            tigraphy (From Brahana and Broshears, 2001). See Figure 2 for location of cross-section.

-------
(IDW) method. IDWwas chosen because it is
effective in contouring limited numbers of
points. Best fit was determined by minimization
of the root mean square (RMS) error. These
interpolated surfaces provide a baseline for
determining where additional data are needed
to constrain the three-dimensional lithostrati-
graphic and hydrostratigraphic  models neces-
sary in subsequent project phases.

Geologic Background
The Mississippi Embayment
The Mississippi Embayment (ME) is a broad
south-plunging trough filled with Upper
Cretaceous and Paleogene marine to non-
marine sediments overlain by a veneer of
Pliocene and Quaternary fluvial sediments
and Pleistocene      (Gushing et al., 1964;
Cox and Van Arsdale, 1997). At the southern
margin of the ME, where it merges with the
Gulf Coast, the post-Cretaceous sedimentary
fill is approximately 2 km thick and the embay-
ment is approximately 600 km across from
WNWto ESE (Figure 3). The southern margin
of the ME also corresponds to the craton-ward
limit of the Appalachian-Ouachita detachment
(Thomas, 1991). The trend of the trough of the
ME roughly follows the ancient Reelfoot Rift
(Ervin and McGinnis, 1975), suggesting that
Precambrian-early Cambrian extensional struc-
tures exert a prominent control on the tectonic
evolution of the ME (Howe and Thompson,
1984; Marshak and Paulsen, 1996; Csontos et
al., 2008).

The geologic formation and evolution of the
Mississippi Embayment was first examined
in detail by Stearns (1957) and Stearns and
Marcher (1962). Their general  interpretation
involves structural doming of the northern
ME during Early Cretaceous time to form the
Pascola Arch followed by deposition of the
Upper Cretaceous Tuscaloosa Fm. around
the eastern and southern margins of the
arch.  Subsidence in the region of the Pascola
Arch followed, leading to the broad, shal-
low ME basin.  The northern ME was filled
subsequently with Upper Cretaceous through
upper Eocene       as well as thin sections
of Oligocene and Miocene deposits to the
south where the ME merges with the Gulf
Coast (Gushing et al., 1964).  Formation and
subsidence within the ME have been variably
interpreted to be  related to distal effects of the
Appalachian-Ouachita orogenesis (Gushing
et al., 1964)  or opening of the Gulf of Mexico
(Ervin and McGinnis, 1975; Kane et  al., 1981;
Braile et al.,  1986). More recently, Cox and
Van Arsdale, 1997; Van Arsdale and Cox, 2007
proposed that the ME formed in response to
the track on the Bermuda hot spot beneath the
weak crust underlying the Reelfoot Rift. As
the hot spot         beneath the ME it caused
magmatism along the ancient rift margins as
well as doming and erosion. Following pas-
     of the hot spot, the  topographic dome
underwent thermal subsidence leading to
accommodation      that was filled by the
Upper Cretaceous through Eocene succession.
The magmatic and exposure history of the ME
is consistent with the hot spot migration hypoth-
esis (Cox and Van Arsdale, 1997; Van Arsdale
and Cox, 2007); however, detailed stratigraphic
     of the model have yet to be conducted.

Sedimentary deposition within the Mississippi
Embayment  began in the early Cretaceous,
mainly in the southeastern and southwestern
portions of the ME where the Gulf Coast
system merges with  ME      (Gushing
et al., 1964).  Lower  Cretaceous       are
largely missing in the central ME, where an
angular unconformity exists between Upper
Cretaceous strata and older deposits (Murray,
1961; Cox and Van Arsdale, 1997).
Upper Cretaceous gravels (Tuscaloosa Group)
were deposited in a crescent-shaped arc along
the eastern margin of the ME (Stearns and
Marcher, 1962). These deposits       upward
and westward into the marginal marine and
marine       of the Eutaw Fm. and Selma
Group. The Cretaceous deposits within the
ME are thickest along the southeastern and
southwestern margins and thin substantially in
the northern and northwestern ME (Gushing et
al., 1964; Hosman, 1996). The upper contact
of Cretaceous deposits in the Gulf Coast is
locally disturbed and erosional, which has
been interpreted  to have  resulted from tsunami
associated with the K-T impact event (Smit et
al., 1996).  No stratigraphic evidence of tsunami

-------
at the K-T boundary is observed in the northern
ME (Patterson, 1998), and erosion is consistent
with regression associated with relative
level fall.

The bulk of sedimentary deposition within
the ME occurred during the Paleocene and
Eocene, and is recorded in Midway, Wilcox,
Claiborne, and Jackson group sediments
(Gushing et al., 1964; Hosman, 1996; Van
Arsdale and TenBrink, 2000). The Cenozoic
stratigraphy is discussed in detail below, with
most of the emphasis placed on the Wilcox and
Claiborne groups that include the major Tertiary
aquifers in the ME (Hosman et al., 1968;
Hosman and Weiss, 1991). The post-Jackson
sedimentary history of the ME includes minor
deposition of Oligocene and Miocene      in
the southern-most part of the ME and wide-
spread non-deposition and/or erosion during
the Oligocene and Miocene throughout the
central and northern ME (Gushing et al., 1964;
Hosman, 1996; Van Arsdale and TenBrink,
2000). The Pliocene and Pleistocene deposi-
tional history of the ME is mainly that of fluvial
incision and terrace formation (Fisk, 1944;
Austin et al., 1991;  Saucier, 1994; Blum et al.,
2000; Rittenour et al., 2005; Van Arsdale et al.,
2008).

The structural history of the Mississippi
Embayment is strongly influenced by the
structural grain of the Reelfoot Rift (Howe and
Thompson, 1984; Johnston and  Schweig,
1996; Cox et al.,  2001 a; Parrish and Van
Arsdale, 2004; Csontos et al., 2008; Martin,
2008). However, additional structural control is
provided by NW-SE-trending  lineaments and
fault zones (Howe and Thompson, 1984; Stark,
1997; Cox, 1988; Cox et al., 2001 b), creating
a series of structural blocks that tilt and rotate
in response to applied compressional
(Csontos, 2007). The effects of these fault
structures on the Tertiary stratigraphy in the
study     have been studied mostly along
the southeastern margin of the Reelfoot rift in
Tennessee and Arkansas (Cox et al., 2001 a;
Parrish and Van Arsdale, 2004; Csontos et al.,
2008), but a recent study by Martin extended
these investigations into  northern Mississippi
(Martin, 2008), thus, encompassing the
MERGWS study area.

Current seismicity in the northern ME is
focused along the NE-trending New Madrid
fault system (Schweig and Van Arsdale,  1996),
although       seismicity also defines the
southeastern structural  margin of the ancient
Reelfoot rift (Chiu  et al., 1997; Cox et al.,
2001 a). During the Holocene, however,  both
the southeastern structural margin of the
Reelfoot rift (Cox et al.,  2006) and the NW-SE-
trending Sabine and Arkansas River fault zones
(Cox et al.,  2007)  may have defined loci of
seismicity, indicating that Holocene seismicity
is not confined in time or       to the New
Madrid zone.

Tertiary and                     of the

The Tertiary and Quaternary stratigraphy of
the Mississippi Embayment  (ME)  has
reviewed in several regional papers (Table 1)
(Stearns, 1957; Gushing et al., 1964; Hosman,
1996; Van Arsdale and TenBrink, 2000) as
well as in state-specific  publications (Table 2)
(Dockery, 1996; McFarland,  2004). Details of
the stratigraphy have been developed in local
studies (e.g., Moore and Brown, 1969; Russell
and Parks,  1975; Fredericksen etal., 1982;
Thompson, 1995)  that are not always amenable
to regional correlation.  To better enable corre-
lation of local geology to the regional scale, it is
important to understand the depositional char-
acter of the geologic units of interest and use
this information as identifiable markers during
interpretation.  Such information is presented
below. The details and  associated correlation
problems are discussed in the results section.

The basal Midway Group disconformably
overlies Cretaceous (Maestrichtian) strata
across the entire ME. The Maestrichtian-
Danian     boundary is a type I unconformity
(Mancini and Tew, 1991), indicating exposure
occurred across most or all  of the continen-
tal shelf.  The      marine sands of the
Paleocene Clayton Formation grade abruptly
into marine clay and fine sand of the Porters
Creek Clay.  The Porters Creek Clay is marine
throughout  the entire ME (McFarland, 2004;

-------
Table 1.     Geologic and hydrostratigraphic units correlated throughout the Mississippi Embayment (From Hart
              etal.,2008).
1   I
                       lOOSlANA
                                                    MISSOURI
       B
       I
      Ls_
       SS
      I i
       |
       Ģ
                                                                          TMNESSEE
                                                                                      MISSISSIPPI
                        Ftrmwn
                LZ,
                            Sptra
iv.i
                 If
                                                                    ^ ntf !ses5 deposits
                                                   Not prMBitin study™
                                                               SSSil
                                                                                        Sparta
                                                                          Old BTMSI*
                                                           Mxh.iy6.aup
                                                                                                         r! sti.cn
                                                                                                         s San*!
                                                                                                                r-*s^—tS~7
                                                                                                             M,*vwtoi.I,M5
    '(.WiWr C!*temŧ *awsŧ! rtt'tiiSst &* ij^ssl W;"ŦE*ŧ ai^f,h%?'S Kiw* J^1r?ŧs at M*tĢlŦ&!J?Jŧ
                                                                                                         MGii^ifi(JfiSWN!3Sfflitt3ndWSE5&, 1^!

-------
Table 2.    Geologic correlation diagram for Cenozoic strata in Mississippi (from Dockery, 1996).

-------
Fredericksen et a!., 1982; Russell and Parks,
1975), suggesting that its original extent may
have been substantially greater.  The upper
Midway Group in Mississippi includes the
Naheola Fm (Dockery, 1996), which is not
defined in either Arkansas or Tennessee. The
Naheola includes two members,  the Oak Hill
and the Coal Bluff, which are well-defined in
eastern central Mississippi. The  Oak Hill
conformably on the Porters Creek Clay and
represents a coarsening-upward  sequence that
includes interbedded clay, silt, and fine-grained
sand (Thompson,  1995). Coal Bluff rests with
unconformity on the Oak Hill and includes
fine- to coarse-grained sand interbedded with
clay, silt, and lignite (Thompson,  1995). The
upper part of the Coal Bluff is highly weathered
and contains bauxitic to kaolinitic clays.  Similar
weathered strata are observed in exposures
of the basal "Wilcox" Fm. in southwestern
Tennessee (Russell and Parks, 1975) suggest-
ing that a Coal Bluff equivalent is present in
western Tennessee.

The Wilcox Group      with unconformity on
the  underlying Midway Group, although the
lithological distinction between Midway and
Wilcox      is locally gradational across
the  boundary (Hosman, 1996). In
central Mississippi, which is the southeastern
corner of the ME, four formations define the
Wilcox Group: Nanafalia, Tuscahoma, Bashi,
and Hatchetigbee formations (Dockery, 1996;
Thompson, 1995). The Nanafalia Formation
consists of two members, the Gravel Creek
Sand and Grampian Hills members. The
Gravel Creek Sand contains a prominent sand
interval interbedded with clay, silt, sand, and
lignite.  The Grampian Hills is generally finer
grained than the Gravel Creek Sand with a
     sand interval followed by clay, silt and
fine- to medium-grained sand interbedded with
multiple lignite seams (Thompson, 1995). The
overlying Tuscahoma Fm. is lithologically similar
to the underlying Grampian Hills  member of
the  Nanafalia Fm.; however, two  depositional
cycles of      sand and overlying fine-grained
clay, silt, sand, and lignite are observed.
Furthermore, the Grampian Hills  contains
prominent correlative marginal marine intervals
(Dockery and Thompson, 1996),  whereas the
Tuscahoma is almost entirely non-marine,
except near the Alabama      line.  The Bashi
overlies the Tuscahoma Fm. disconformably
and represents the basal Eocene strata in
the Gulf Coast (Mancini and Tew, 1991). The
Bashi Formation is distinctive and mappable
in Mississippi only near the Alabama     line
where it is a marine interval with glauconitic
sands and marls (Thompson, 1995).  The
Bashi grades laterally into       sands in the
Hatchetigbee Formation in western Alabama
(Gibson, 1982), and shows similar relationships
in Mississippi (Thompson, 1995; Thompson,
2003a; b; c; d). The Hatchetigbee Fm. contains
interbedded clay, silt,  sand, and lignite.

The Wilcox Group in the central and northern
ME comprises three formations: The Old
Breastworks,  Fort  Pillow Sand, and Flour
Island formations (Table 3) (Moore and
Brown, 1969; Hosman,  1996; Van Arsdale and
TenBrink, 2000; Brahana and Broshears, 2001).
Frederiksen et al. (1982), in a biostratigraphic
study of the New Madrid test wells in south-
eastern Missouri, correlate the Old Breastworks
to the Naheola Fm (Oak Hill member) based
on dinoflagellate species and lithologic similar-
ity, suggesting that the Old Breastworks Fm.
belongs to the Midway Group. The Old
Breastworks Fm. is not defined in surface
exposures in western Tennessee, where the
Wilcox Fm.     directly on Porters Creek Clay
(Russell and Parks, 1975). The Fort Pillow
Sand is a coarse sand that thickens into the
axis of the ME and is roughly correlative to the
Nanafalia Fm. (Gushing etal., 1964; Hosman,
1996). The Flour Island Formation is mainly
lignitic silt with interbedded clay and fine sand.
The lower part of the  Flour Island is calcare-
ous and glauconitic at the Fort Pillow test well
(Moore and Brown, 1969), but only non-marine
strata are present  in the New Madrid test wells
(Frederiksen etal., 1982).

The Wilcox Group is         along Crowley's
Ridge in northeastern Arkansas, but is undi-
vided. The composite thickness  is approxi-
mately 780 ft thick and composed of sands, silt,
clay,  and lignite  (Meissner,  1984). Significant
lignite seams are present only in the upper half
of the Wilcox Group.

-------
 Table 3.    Lithostratigraphy and hydrostratigraphy in the Memphis, Tennessee, area (From Brahana and
           Broshears, 2001).
System
Ouak-nwrs

*r-


!„„Ŧ




SeJles
HuloeftKam!
PlriiHttTK'
"=?J

Em-cnr
	 •! 	 	




Group



	 _ 	 •• 	 	 _


w,™



Stratigrsphic
unit
.,„,,„„
Ux^s
RuvialOqxKiw
am! uĢ>pe? pan of
Memphis Sand
rSUO-foofsami)
Fliwr Mind
Fonmucm
fort hlhsw Sand
ri*oo-ffxŧr iand}

t . I S

Thick-
ness
ŧ,Ŧ
0 65
0- 1 00
0 Ktf
500- 8'X)
140010
Ŧ.*ŧ

180 •35-0

HydroiOgEc unfe!





Confmm, in,.
Fort Ptllow an ill r



LiUhology aŦ$ hydroEogfe significance
MM jMnl Mi , ' 1 ul Mi*.* !h MJ M ji il h nn J ij *. i
*Ku ,. .-in Ml i • IHMHITU' Ithiv Uli t Ihi MM t
1U* J Hh 1 '1 * lit r (UldEM Kill trill ll U Jl U ŧ 11 tl '
Nfl M s J^fii \ i f t i f lifll
Mil illy dj iff I in iJ I'1 ft^ipti init ii 't i ft! n m tit; hn ' ar t f
< ulK its'ii nui I1 tŧ uifth Muts ' 'f i J E thL Ms SE if jt •ŧ i
f t i thi 11 i i s 1 !i mi tit *-|ulK T _ i iuf J>J.ns. iu'irt in ir
vtrtr I>MU.I i h it Ih, Ou> t ŧ j (t
s%:f;'\ivi^f;;if/::Vir;,^:
f JA 1 1 Mn J m J h Hi B t tuu it s i ht u ! ; m JitUi i f ( n s
u ifi Ŧ il i [ pi i |!*M Ih i liiKfti tjioiisni tl i iitH is'iji-. J ttSi M sfi ^ i '
Hn ill sŦn 1 in f Un t i t j,! tit t ( i f lit ^ jrtJU* <. fit j

Ktnuli 11 v.hun M U >i luu ti
The Claiborne Group rests disconformably
on the Wilcox Group deposits across the ME,
suggesting that a type 1 sequence boundary
exists between the units (Mancini and Tew,
1991; Ingram, 1992).  In northern Mississippi,
the lower and middle  Claiborne includes five
formations (Dockery,  1996): Meridian Sand,
Tallahatta  Formation,  Winona Sand, Zilpha
Shale, and Kosciusko Formation. The Meridian
Sand is fine- to coarse-grained sand with char-
acteristic crossbedding (Gushing et al., 1964).
Although Thomas  (1942) in a comprehensive
study of the Claiborne in Mississippi assigned
the Meridian to the Wilcox Group, later studies
have confirmed its proper inclusion within the
Claiborne  (Bybell and Gibson, 1985; Hosman,
1996). The Tallahatta Formation consists
of dark greenish-gray clay and siliceous  to
glauconitic siltstone and fine- to coarse-grained
sandstone in the Basic City Shale member
and generally non-glauconitic fine- to medium-
grained sand and  gray clay in the Neshoba
sand member (Thomas, 1942). The Winona
Sand is predominantly medium- to coarse-
grained glauconitic sand and is easily identified
in surface exposures by its dark red weathering
color. The Zilpha Shale is a dark gray, carbo-
naceous, glauconitic, and sparsely fossiliferous
clay (Gushing et al., 1964). The Winona Sand
and Zilpha Shale are only observed in central
and southern Mississippi, although correlative
but lithologically distinct intervals are described
in both Arkansas and Tennessee (Moore, 1965;
Hosman, 1996). The Kosciusko Fm. consists
of medium-grained sand with interbedded light
gray, light greenish-gray,  and rarely dark gray
shale (Thomas, 1942).

The lower and middle Claiborne Group in
southeastern Arkansas includes the Carrizo
Sand, Cane River Formation, and Sparta
Sand (Gushing et al., 1964; Payne, 1968;
1972; 1975). The Carrizo Sand is correlative
to the Meridian Sand in Mississippi (Payne,
1975; Hosman,  1996).  The Cane River Fm. is
roughly equivalent to the Tallahatta Formation,

-------
Winona Sand, and Zilpha Shale in Mississippi
(Payne, 1972). The Sparta Sand is correla-
tive to the Kosciusko Formation in Mississippi
(Hosman, 1996),  North of the 35°  parallel, the
Cane River pinches out and the entire lower
and middle Claiborne section is dominated by
the Memphis Sand (Hosman, 1996).  Similarly
in western Tennessee, Moore (1965)  cor-
       the Tallahatta Formation and Sparta
Sand to the Memphis ("500-foot") Sand. The
Memphis Sand was formally defined  in the Fort
Pillow test well (Moore and Brown, 1969) in
Lauderdale County, Tennessee, and later corre-
lated throughout the northern ME (Frederiksen
et al., 1982; Parks and Carmichae!, 1990a;
Hosman, 1996). The Memphis Sand is pre-
dominantly fine- to coarse-grained  sand with
subordinate carbonaceous and lignitic silt and
clay and lignite (Parks  and Carmichael, 1990a).
Clay intervals correlative to the Basic City
Shale and Zilpha Shale are locally identified
(Moore, 1965; Parks and Carmichael, 1990a).

Throughout the  study area, the Kosciusko Fm.,
Sparta Sand, and Memphis Sand are overlain
with disconformity by the upper Claiborne Cook
Mountain and Cockfield Formations (Thomas,
1942; Gushing et al., 1964; Moore and Brown,
1969; Frederiksen et al., 1982). The  Cook
Mountain Fm. in central Mississippi consists of
a lower glauconitic, fossiliferous sandy marl or
limestone overlain by sandy carbonaceous clay
(Thomas, 1942; Hosman, 1996). However, in
western Tennessee the Cook Mountain Fm. is
mainly  silt and clay with local intervals of fine
sand (Parks and Carmichael, 1990a). The con-
tact between the Cook Mountian and Cockfield
formations is conformable and transitional. In
central Mississippi, the sandy shale of the
Cook Mountain  Fm. grades upward into sand,
lignitic  silty shale,  and lignite of the Cockfield
Formation (Thomas, 1942). The lithology of the
Cockfield Fm. is remarkably consistent across
the northern ME (Moore and Brown,  1969;
Frederiksen et al., 1982; Parks and Carmichael,
1990b; Hosman, 1996).

The Jackson Group has limited extent in the
northern and central ME, and is given only
formational status in Tennessee. The Jackson
Formation crops out along the Mississippi River
bluffs in western Tennessee and along the
southern part of Crowley's Ridge in Arkansas
(Gushing et al., 1964). The Jackson
overlie the Claiborne Group with disconformity
and typically include fossiliferous, glauconitic
sandy marl that grades upward into calcare-
ous clay and locally sand in central Mississippi
(Hosman, 1996). The Jackson Formation in
western Tennessee is lithologically indistinct
from the underlying Cockfield Fm. and is typi-
cally not differentiated (Parks and Carmichael,
1990b; Moore and  Brown, 1969).

The upper surface  of the Paleocene-Eocene
ME sedimentary system is a time-transgressive
erosional surface upon which Pliocene through
modern stream deposits and  late Pleistocene
loess have been laid (Fisk,  1944; Potter,
1955; Austin et al.,  1991; Saucier, 1994; Van
Arsdale et al., 2008). Because the sequence
is associated with the progressive,  though
punctuated, denudation history of the ME, the
oldest deposits are at the highest interfluvial
elevations and the youngest deposits are within
the modern-day valleys. The  Pliocene Upland
Complex, also known as the Lafeyette Gravel
(Potter, 1955), is present in western Tennessee,
northwestern Mississippi, and along Crowley's
Ridge in eastern Arkansas  (Austin  et al., 1991;
Van Arsdale et al.,  2008). Van Arsdale  et al.
(2008)  used  an extensive borehole        to
map the distribution of the Upland Complex
throughout the region and demonstrate its
origin as an ancient high-level terrace of the
Mississippi River, potentially as much as
5.5 Ma old. Subsequent incision and subse-
quent terrace formation has led to formation of
several terrace levels and associated sand and
gravel deposits along the Mississippi  River-
Ohio River valley system (Austin et al.,  1991;
Saucier, 1994; Blum et al 2000; Rittenour et al.,
2003; 2005)  and western Tennessee tributar-
ies (Saucier, 1987;  Rodbell, 1996; McCIure,
1999).  Late  Pleistocene terraces were further
mantled with loess  in the region (Austin et al.,
1991; Rodbell et al., 1997; Rutledge et al.,
1996; Markewich et al., 1998). The modern
Mississippi Valley alluvium consists largely
of gravel and sand  capped by silt and
(Saucier, 1994). Pleistocene  depositional pat-
terns within the Mississippi  Valley appear to be
strongly affected not only by glacial processes

-------
and climate (Saucier, 1994; Blum et a!., 2000;
Rittenour et al, 2005), but also tectonic subsid-
ence and uplift along orthogonal Reelfoot Rift
faults (Csontos et al., 2008).

Hydrostratigraphic Units within the Central
          Embayment
The lithostratigraphic units described above
are divided into a series of hydrostratigraphic
units (Tables 1 and 3).  Hydrostratigraphic
units are defined       on their ability to
produce water at an efficient rate.  Aquifers
are water-producing zones and confining units
are generally poor water-producing zones,
but more importantly provide confinement to
water in underlying and overlying aquifers.
The hydrostratigraphic terminology applied
to the ME has changed over the      120
years as stratigraphic studies have better
defined the lithology and extent of units, and
hydrogeologic studies have better defined the
water-producing zones  and their hydraulic
properties. As mentioned previously, defini-
tion of  hydrostratigraphic units vary depending
on the       of studies. For example, local
studies of ground water tend to use state- or
subregion-based nomenclature, such  as those
applied in  the Memphis area (Criner and Parks,
1976; Brahana and Broshears, 2001). Regional
     studies use  more generic nomenclature,
such as that defined for the ME by the USGS
Regional Aquifer-System Analysis (RASA)
(Hosman and Weiss, 1991).  Most recently, the
USGS  has completed a regional hydrostrati-
graphic analysis focusing on the ME (Table 4)
(Hart and  Clark, 2008; Hart et al.,  2008) as a
part of the Mississippi Embayment Regional
Aquifer Study (MERAS). For the purposes
of the present study, which is subregional in
scale, the  regional hydrostratigraphic terms
from Hart  et al. (2008) with some modifica-
tions discussed below will be applied to the
general discussion (Table 1), although the local
nomenclature in the Memphis area (Brahana
and Broshears, 2001) will be applied to more
detailed discussions.

The Tertiary  ME aquifer system is  confined at
the     by the Midway confining unit. The
clay-rich nature of this unit limits         of
water;  however, water could potentially move
through this and other confining units along
faults (Kingsbury and Parks, 1993). Regionally,
two aquifers are defined within the Wllcox inter-
val, the Lower and Middle (Table 1).  However,
within the study     the Middle Wilcox aquifer
is not distinguished from the lower Memphis
aquifer (lower part of Memphis Sand in Table
1) north of the Mississippi-Tennessee      line
(Thompson, 2003a, b,  c, and d). The Lower
Wilcox aquifer is equivalent to Fort Pillow Sand
in western Tennessee  (Parks and Carmichael,
1989) and northeastern Arkansas (Brahana
and Broshears, 2001)  and the sandy upper
part of the Nanafalia and lower part of the
Tuscahoma (Hosman,  1996). The  Lower Wilcox
is confined  by the underlying Midway confining
unit and fine-grained intervals within the overly-
ing  Flour Island Formation  (Tennessee and
Arkansas) and Tuscahoma Formation (northern
Mississippi). The  Flour island is a confining unit
within the northern ME.

The Claiborne interval includes three regional
aquifers. In northern Mississippi and adjacent
Arkansas, the Lower and Middle Claiborne
aquifers are          by the Lower Claiborne
confining unit.  However, the Lower Claiborne
confining unit laterally  pinches out  near the
Tennessee-Mississippi stateline (and in
adjacent Arkansas), such that the Lower and
Middle Claiborne aquifers merge to form the
Memphis aquifer in western Tennessee and
adjacent Arkansas (Hart et al., 2008; Hosman
and Weiss,  1991;  Parks and Carmichael,
1990a). The Middle Claiborne confining unit
is equivalent to the Cook Mountain Formation
throughout the study      (Hart et al., 2008;
Hosman and Weiss, 1991;  Parks, 1990).
Graham and Parks (1986), Parks (1990),
Bradley (1991), Parks  and Mirecki  (1992),
Parks et al. (1995), Larsen et al. (2003),
Waldron et  al. (2009), and others have noted
that the Middle Claiborne confining unit is
locally absent or contains transmissive fades
which permit vertical recharge to the Memphis
aquifer. The Upper Claiborne aquifer, within
the Cockfield Formation, is generally thin and
discontinuous in the study      and is thickest
     of the Mississippi alluvial valley (Parks
and Carmichael, 1990b). The Upper Claiborne
aquifer is locally unconfined in western

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Tennessee, but also has regions of confinement
provided by the overlying Jackson confining
unit, which is also regionally discontinuous due
to late Cenozoic erosion (Hosman and Weiss,
1991).

The upper Cenozoic stratigraphic units rep-
resent continental deposits that partially infill
valley systems (fluvial terrace and alluvial
valley deposits) or mantle regional upland
(loess).  As such, the correlative hydrogeologic
units are present within topographically distinct
regions  of the study area. The Mississippi
Alluvial aquifer is present beneath the modern-
day Mississippi  River valley (Boswell et al.,
1968; Brown, 1947; Arthur and Strom,  1996;
Ackerman, 1996; Csontos, 2007;  Hart et al.,
2008). The surficial (shallow) aquifer beneath
the uplands of western Tennessee and north-
ern Mississippi includes  several distinct parts
(alluvial and fluvial-terrace deposits of tributar-
ies, and the upland gravels), which may or may
not be in hydraulic communication. Alluvial
deposits in western Tennessee and northern
Mississippi tributary valleys  are of limited
lateral extent and generally thin upstream from
confluence with the Mississippi alluvial valley
(Saucier, 1994;  McClure, 1999; Velasco et al.,
2005, 2002; Stevens, 2007;  Martin, 2008).  The
fluvial-terrace deposits are common along
the tributary valley margins (Krinitzky, 1949;
Saucier,  1987) but also of limited extent. The
Upland Complex gravels are present beneath
the highest upland surfaces in an extensive, but
discontinuous belt in westernmost Tennessee
and Kentucky (Van Arsdale  et al., 2007; Potter,
1955). Similar deposits are known to exist in
northern Mississippi (Dockery, 1996), but have
not been well studied. In all        the surficial
aquifer is overlain by variable  thicknesses of
either loess or reworked loess (alluvial silt)
(Hosman, 1996; Dockery, 1996; Ackerman,
1996), which  tends to retard downward infiltra-
tion of recharge to the surficial aquifer (Brahana
and Broshears,  2001).

Geologic
For the hydrostratigraphic analysis, the
project footprint was enlarged to include 29
counties (Figure 4); 8 in  eastern Arkansas
(Mississippi, Craighead,  Reinsert, Cross,
Crittenden, St. Francis, Lee, and Phillips
Counties); 9 in northern Mississippi (Tunica,
Coahoma, Benton, Quitman, Panola, Lafayette,
Marshall, Tate, and DeSoto Counties); and
12 in western Tennessee  (Lake, Obion,
Dyer, Gibson, Lauderdale, Crockett, Tipton,
Haywood, Fayette, Hardeman, Madison, and
Shelby Counties). The combined study
is approximately 16,500 square miles (42,700
square kilometers).  It is important to note that
consideration of a footprint larger than the eight
counties of the overall project is necessary to
evaluate subregional trends in stratigraphic
variation, as well as local  variations.

The main source of     is geophysical logs
(also called e-logs or wireline logs) from water
wells and, oil and lignite exploration boreholes.
Of the 17,000 logs available in the 28 county
area, 542 were evaluated (see Appendix
Geophysical Logs) and only 378 were deep
enough  (depth > 500 ft) to be useful in
ing the characteristics of the  Memphis aquifer
(Figure 4) and even fewer were available
for assessing the characteristics of the Fort
Pillow aquifer.  Most of the logs were obtained
from four sources: the GWI log library at The
University of Memphis, USGS --Tennessee
Water Sciences Center, USGS - Arkansas
Water Sciences Center, Mississippi Department
of Environmental Quality,  and private well  drill-
ing contractors. The log quality was generally
good; however,  most locations and elevations
were estimated from topographic maps  or
UTM coordinates. Any log with an overall rank
higher than 5 was included in the project for
potential analysis (see Table App4 in Appendix
Geophysical Logs).

The geophysical logs commonly included
signals from one or more tools: gamma ray,
SP, or resistivity (Figure 5). Gamma logs are
generally responsive to clay minerals and  thus
differentiate clay versus sand units; although
gamma  signals are     responsive to clays in
unconsolidated sediments. In addition,  sub-
stantial kaolinite, which gives a muted gamma
signal, is present in the matrix in the sand and
many clay intervals (Lumsden et al., 2009).
Thus, the most accurate picks could be made
from logs with all three signals.

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              92°0'0"W
                                                 90°0'0"W
                                                                                    88°0'0"W
        36°0'0"N
        34°0'0"N
                                                                                              36°0'0"N
                                                                                              34"0'0"N
              92°0'0"W
                     25    50
                                         I
                                        100 Miles
90°0'0"W                            88°0'0"W
           Legend
             •    Well
           |      Major rivers
           |    | Geologic investigative extent
           |	| Crowley's Ridge
           [_   i Northern Mississippi embayment
                 County
           	State
           Topography (USGS 30m)
           Elevation (ft) (MSL)
                 High : 2,250
                                                            a
                                                                  Low : 50
Figure 4.     Map of the study area showing the distribution of wells >500 ft depth used in the study. Elevations
              are contoured in feet above sea-level.

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                MSJ002
              LSE 310 feet
Cockfield Fm.
Cook Mountain Fm.
Memphis Sand
Flour Island Fm.
Fort Pillow Sand
                                	6001
                                    300'
                                — SLO
                        -300'
                                    -600'
           Gamma ray
             log
                                    -900'
            Resistivity
              log
Figure 5.
Example of gamma ray and resistivity
borehole log response in the study
area. MSJ002 is the well identifica-
tion; LSE is the land surface eleva-
tion; Depths are in feet.
Stratigraphy
The lithostratigraphic units defined in the
study area and identified in the cross-sections
are shown in Table 4.  The correlations follow
Hosman (1996) and Hart et al. (2008) with
some minor differences noted below.

The upper units identified in the geophysical
logs include the Pleistocene loess, Mississippi
Valley alluvium, fluvial terrace gravels, and
Eocene Jackson Formation, all of which are
discontinuously present across the study area.
The Eocene Cockfield and Cook Mountain
formations are generally continuous  across
the study area and dominated by shale with
variable thicknesses of sand and silt. Their
log response is similar in some cases and
clear delineation of each formation was not
always possible. The clay-dominated interval,
80 to 100 ft thick, overlying the top of the
Memphis Sand was generally assigned to
Cook Mountain Formation and overlying strata
of variable quantities of sand, silt,  and clay as
much as 250 ft thick assigned to the Cockfield
Formation.

The Memphis Sand and correlative formations
in Mississippi and Arkansas are continuous
throughout the three-state region (Table 4). The
top of the Memphis  Sand (or equivalent strata)
was typically determined by maintaining the
thickness (approx. 700-800 ft from the top of
the Flour Island or Hatchetigbee Formation in
the center of the ME) observed in  neighboring
logs and identifying  recognizable intervals (e.g.,
Zilpha Shale and Kosciusko Sand  and their
correlatives). The base of the Claiborne Group
overlies the  Flour Island Formation, which is
a well-defined fine-grained unit throughout
the northern ME. The Memphis Sand in the
northern ME is subdivided into three informal
members (upper middle, and lower) that corre-
late to the Carrizo Sand, Cane River Formation,
and Sparta Sand in southeastern Arkansas and
related strata in northern Mississippi.

The Wilcox Group stratigraphy is continu-
ous throughout the region, although fades
changes in northern Mississippi obscure
correlations.  For example, the correlation
between the Flour Island Formation and the
Tuscahoma and Hatchetigbee formations in
northern Mississippi is not well constrained.
For consistency with Thompson's (2003a,  b, c,
and d) field mapping in northern Mississippi,
the uppermost sand of the Wilcox  Group is
assigned to the Hatchetigbee Formation. The
Nanafalia Formation and lowermost sand of
the Tuscahoma Formation are correlated to
the Fort Pillow Sand, which is lithologically
consistent but does not consider disconformi-
ties observed within the Wilcox section in
Mississippi (Thompson, 1995; Mancini and Tew,
1991).

The Old Breastworks Formation in western
Tennessee and northeastern Arkansas is
correlated to the Naheola Fm. in northern
Mississippi (Figure 4),  as suggested by pale-
ontological work by  Frederiksen et al. (1982).

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Table 4.   Proposed lithostratigraphic correlation for the northern and central Mississippi Embayment (modi-
          fied from Hosman and Weiss, 1991).
ERA
Cenozoic
SYSTEM
Quaternary
Tertiary
SERIES
Holocene
Pleistocene
Pliocene
Eocene
Paleocene
STAGE


Jackson
Group
Claiborne
Group
Wilcox
Group
Midway
Group
Arkansas
Southern
Alluvium
Terrace
deposits
Upland Complex
Northeastern
Alluvium
Loess
Terrace
deposits
Upland Complex
Jackson Group
Cockfield Formation
Cook Mountain Formation
Sparta Sand
Cane
River
Formation
Carrizzo Sand
Undifferentiated
Porters Creek Fm.
Tennessee
Western
Alluvium
Loess
Terrace
deposits
Upland Complex
Jackson Fm.
Cockfield Fm.
Cook Mountain Fm.
upper Memphis Sand
middle Memphis Sand
lower Memphis Sand
Flour Island
Formation
Fort Pillow Sand
Old Breastworks
Formation
Porters Creek Fm.
Clayton Formation
Flour Island
Formation
Fort Pillow Sand
Old Breastworks
Formation
Porters Creek Clay
Clayton Fm.
Mississippi
Northern
Alluvium
Loess
Terrace
deposits
Upland Complex
Yazoo Clay
Moody's Branch Fm.
Cockfield Fm.
Cook Mountain Fm.
Kosciusko Sand
Zilpha Shale
Winona Sand
Tallahatta Fm.
Meridian Sand
Hatchetigbee Fm.
Bashi Fm.
Tuscahoma Fm.
Nanafalia Fm.
Naheola Fm.
Porters Creek Fm.
Clayton Fm.
This correlation brings regional parsimony to
the Gulf Coast and northern ME lithostratigra-
phy and is consistent with weathering horizons
observed at the top of the Naheola Fm. in
Mississippi (Thompson, 1995) and the basal
Wilcox Formation in southwestern Tennessee
(Russell and Parks, 1975). The re-assignment
is also consistent with the fades changes
between the Old Breastworks Formation and
Fort Pillow Sand (Moore and Brown, 1969),
and phosphatic pebbles, which are commonly
associated with transgressive fades above
major disconformities, at the base of the Fort
Pillow Sand in the Fort Pillow test well.

Cross Sections
Seven  cross sections were prepared (Figure
6): one parallel to the Mississippi  River (G-G')
(Figure 7), and six perpendicular  to the
first (A-A' to F-F') (Figures 8-13).  Because
of the size of the cross-sections these are
presented as plates at the end of the  docu-
ment.  Stratigraphic units from the top of the
Cretaceous to the surface were interpreted
from the geophysical logs and correlated
along the length of the sections, except where
removed by erosion.  The logs are numbered
consecutively on each section from west
(or south) to east (or north).  The bases of
Quaternary formations are designated by
red lines and those of Tertiary formations are
designated with blue lines. Because of its
hydrogeologic significance, the Memphis Sand
and correlative formations comprising lower
and middle Claiborne aquifers are bound by
green lines.  Red vertical dashed lines repre-
sent faults identified by Csontos (2007).  Green
vertical dashed lines represent faults inferred
based on the present Stratigraphic study. The
sections are described individually below
beginning with section G, followed by sections
A through  F

Section G-G' (Figure 6) serves as a regional
key section from southwest to northeast within
the northern ME.  Sections A, B,  D, E, and  F
are correlated to logs on section G-G'. The

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                 36'0'0-N-
                                                                          36-0'0'N
                                                                          -34-0'0-N
                          25   SO
90'OirW                     B8'0'0"W

          Legend
Miles
           •   Well control
          ^^ Cross-section line
              Major rivers
            j Geologic investigative extent
              Crowley's Ridge
          L   J Northern Mississippi embayment
          	 State
              County
Figure 6.    Locations of cross-section lines A-G in the study area.
overall trend in section G-G' is that of progres-
sive thinning of all Tertiary stratigraphic units
from southwest to northeast (Plate 1). Faults
(green vertical dashed lines) were inserted
between logs 3 and 4, 6 and 7, and 13 and 14
to convey inferred offsets.  Fault offsets were
only considered where multiple formations
are offset in a given log, preferably in multiple
cross-sections.  Log signals for Quaternary
units are observed in several logs, but the main
constraint on thickness of Quaternary deposits
is based on surface elevation and the top of
the Tertiary. The Jackson Formation is present
as fine-grained deposits only at the Fort Pillow
test well (log 11) and  to the south of Crowley's
Ridge. The Cook Mountain and Cockfield
formations are dominated by fine-grained
sediments from the south to log 7.  To the
north  of log 7, fining-upward and coarsening-
upward sand to mud intervals are present in
the Cockfield Formation.  Between logs 7 and
         10, local sand bodies are present within the
         fine-grained Cook Mountain deposits. From
         logs 1 to 5, the lower and middle Claiborne
         sections show three distinct units, the Carrizo
         Sand, Cane River Formation, and Sparta Sand.
         The Carrizo and Sparta are nearly all sand,
         whereas the Cane River contains numerous
         sand intervals, none  of which are particularly
         laterally persistent, within an overall mud-rich
         unit.  Winona  and Zilpha Shale equivalents are
         designated; however, they are better concep-
         tualized as comprising  a persistent interval
         rather than as distinct lithologic units. North
         of log 5, the Memphis Sand is present with
         two laterally persistent  fine-grained intervals
         (Basic City Shale and Zilpha Shale equivalents)
         dividing the formation into the three informal
         members (Table 4). These fine-grained inter-
         vals are not single horizons, but rather intervals
         in which silt and clay are consistently present
         (although at slightly higher or lower elevations

-------
in the formation).  The lower and middle
Claiborne section thins from 1350 to 600 ft
from southwest to northeast The Flour Island
Formation is a laterally persistent fine-grained
interval along section G-G', with thin (10 to 20
ft thick) sand intervals observed throughout
the formation.  The Flour Island Formation
thins from 500 to 75 ft thick from log 1 to 13,
respectively. The Fort Pillow Sand varies from
a single amalgamated sand interval (e.g., log
5) to comprising two distinct sand intervals
with a prominent intervening fine-grained unit
(e.g., log 3). It thins from 225 to 125 ft thick
from southwest to northeast The underlying
Old Breastworks Formation is observed in only
four wells in section G-G' and shows an overall
upward-coarsening character in each; however,
it shows the coarsest character in log 13.

Section A-A' is centered on the Mississippi
River and bounded by Crowley's Ridge on
the west and Jackson, Tennessee, on the
     (Figure 6). Prominent fault offsets are
observed     of log 1, along Crowley's Ridge,
between sections 4 and 5,  and near log 8
(Plate 2).  A significant section (120 ft thick)
of Jackson Formation is present at log 8, but
otherwise the Cockfield and Cook Mountain
formations comprise the upper Tertiary sec-
tions along most of the section.  The Cockfield
Formation includes        thick sand intervals,
although consistent fining-  or coarsening-
upward intervals are observed in logs 8 and 10.
The Cook Mountain Formation is dominated by
fine-grained strata at logs 4 and 5, but contains
laterally persistent sand intervals in the upper
part of the formation, especially at log 7. The
Memphis Sand is dominated by sand
of log 8, with only the Zilpha Shale interval
showing potential lateral persistence.  However,
in logs 2 through 5 the Memphis Sand shows
distinct intervals correlative to the Carrizo
Sand, Cane River Formation, and Sparta Sand,
supporting the correlation in the northwestern
ME of the tripartite stratigraphy used in south-
eastern Arkansas. The Flour Island Formation
and Fort Pillow Sand generally show similar
characteristics to that observed in section
G-G', with the Flour Island  showing substantial
thinning toward the eastern and western ME
margins. The Flour Island  is anomalously thick
in log 4, potentially due to the Flour Island
interval containing a fault zone.

Section B-B' was constructed in western
Tennessee (Figure 6) mainly utilizing shallow
exploration borehole logs (total depth < 300 ft.).
The purpose of this section was to        the
utility of the shallow logs. Although the log
signals are quite good (Plate 3), the limited
depth of most boreholes        uncertainty in
the formation picks; thus, decreasing the value
of this cross-section for the overall project
goals. However, section B-B' does illustrate the
sand-rich character of the Memphis Sand along
the basin margin and      for     borehole
control.

Section C-C' extends from Crowley's Ridge
in Arkansas to northwestern  Mississippi, and
       through the Memphis area.  Significant
fault  offsets are inferred between logs 1  and
2, 2 and 3, 4 and 5, 8 and  9, and 10 and 11
(Plate 4).  Faults inferred between logs 8 and
9 and 10 and 11 fall along  trends identified
by Velasco et al. (2005) and Stevens (2007).
The Cockfield and Cook Mountain formations
are the uppermost Tertiary formations along
most of the section with significant subcrop
regions of the Memphis Sand and correlative
Claiborne      in  Mississippi at the north-
western and southeastern  ends of the section,
respectively. The Cook Mountain Formation
is thin and partially removed  by erosion
of the Mississippi River, consistent with stud-
ies by Parks (1990) and  Kingsbury and Parks
(1993). The Memphis Sand is dominated by
sand between logs 4 and 6, but shows two or
more fine-grained intervals west and     of
the central  part of the cross-section.  Some of
the fine-grained intervals appear to correlate
to the Basic City Shale and Zilpha Shale
intervals; however,  others are discontinuous
and vary in their stratigraphic level in the
Memphis Sand. At the Tennessee-Mississippi
     line, the lower part of the Memphis Sand
thickens,  which is interpreted to reflect the
northern  extent of the Hatchetigbee Formation
as mapped by Thompson (2003a; b; c; and
d). The Flour Island Formation in Arkansas
and Tennessee is generally fine-grained, but
a sandy interval is commonly observed in the

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middle of the formation (e.g., logs 2, 4, and 9).
The Tuscahoma and Hatchetigbee formations
are correlated tenuously to the Flour Island
Formation and lower Memphis Sand
on lithological studies in central Mississippi by
Thompson (1995). The Nanafalia Formation
is correlated to the Fort Pillow Sand; however,
the interval is more fine-grained at logs 15 and
16 than typically recorded.  Furthermore, the
Fort Pillow Sand thins extensively from 330 ft at
log 4 to 100 ft at log 13. The Old Breastworks
Formation and Other Midway Group units are
consistent in character along the section, but
thin toward the basin  margins.

Section D-D' extends from western Poinsett
County (west of Crowley's Ridge) in Arkansas
to  southeastern Marshall County in Mississippi.
Although several faults are shown, the most
important offsets exist between logs 2 and 3
(along  the eastern margin of Crowley's Ridge),
and on either     of log 6, which
to  be on a horst block (Plate 5). The Cook
Mountain Formation is present beneath the
Quaternary units between logs 3 and 9, with
part of the Cockfield Formation present only
in  logs 4 and 7. The Memphis Sand is pres-
ent in logs 1 through 9,     of which the
Mississippi Claiborne Group formations are
assigned.  The Memphis Sand is dominantly
sand west of the Mississippi River, but the
clay intervals within the Taliahatta and Ziipha
intervals become increasingly distinct within
northern Mississippi.  Similar to section C-C',
the lower sandy part of the Claiborne thickens
within northern Mississippi as the Hatchetigbee
Formation intertongues with the Flour Island
Formation. As observed in  section C-C', the
Flour Island Formation and  Fort Pillow Sand
increase in thickness toward the center of the
ME in logs 5 through  8 and  10, but thin toward
the margins of the basin. Conversely, the Old
Breastworks Formation and Porter's Creek Clay
retain similar thicknesses in all the Arkansas
logs (the interval has limited representation in
the Mississippi logs).

Section E-E' extends from western Cross
County (west of Crowley's Ridge) in Arkansas
to  eastern Panola County in northern
Mississippi.  Many faults are identified within
the section; however,  the        offsets are
observed along the faults between logs 8
and 9,  11 and 12, 12 and 13, and 16 and 17
(Plate 6). The Cook Mountain and Cockfield
formations are present to varying degrees
between logs 3 and  11, with the Jackson
Formation also observed at log 3, which is
located on Crowley's Ridge. In contrast to the
sections to the north, prominent clay inter-
vals, either within the Cane River Formation
(Arkansas) or Taliahatta  Formation, Ziipha
Shale,  and Kosciusko Formation (Mississippi),
are present in the lower  and middle Claiborne
section in all logs except 1 and 2. As observed
in sections C-C' and D-D', the Flour Island
Formation and Fort Pillow Sand thicken toward
the center of the ME at logs 5, 6 and 8, but thin
toward the margins.  The correlative forma-
tion to  the Fort Pillow Sand (Nanafalia Fm.) in
northern Mississippi is finer grained than the
Fort Pillow Sand and is likely dominated by silt
and clay rather than sand. The underlying Old
Breastworks/Naheola Formation and Porters
Creek Clay appear to thin toward the margins
of the ME, but generally  retain similar log
signatures throughout their respective extents.

Section F-F' is the southernmost SE-NW cross-
section and extends from western St. Francis
County in Arkansas  to southern Panola County
in Mississippi. Only  two  faults are identified
in this cross-section, between logs 8 and 9
and between  10 and 11, both with significant
inferred offsets (Plate 7). The Cook Mountain
Formation is present between logs 1 through 7,
9 and 10, with the Cockfield Formation having
more limited preservation at logs 4 through
7, 9 and 10.  The lower to middle Claiborne
section is sandy at logs  1, 2, 6 and 8, but in
other logs contains significant clay intervals
in the Cane River Formation (Arkansas) and
Taliahatta  Formation and Ziipha intervals.  In
general, the lower Claiborne appears to be
dominated by silts and clay in logs 11, 12, 13,
15, and 16. The trends in the Flour Island and
Fort Pillow Sand intervals are similar to those
observed in section  E-E', with limited evidence
of the sandy Fort Pillow  interval in the correla-
tive Nanafalia Formation at logs 12 and 14.
The Old Breastworks/Naheola Formation and
Porters Creek Clay appear to be thickest near
the center of the ME at log 8 and thin toward
the margins of the basin.

-------
The structure contour maps were made primar-
ily from the high-quality log        used in
cross-section preparation.  Because of limita-
tions in the extent of        formations and the
limited well log dataset, maps are presented
only for Eocene and Paleocene stratigraphic
units.  Furthermore, only the following region-
ally-defined formation or sub-formation bound-
aries are presented:      of Cook Mountain
Formation (Figure 7),      of Kosciusko/
Sparta/ upper Memphis Sand (Figure 8),
of Tallahatta/Cane River/middle Memphis
Sand  (Figure 9),     of the Meridian/Carrizo/
lower  Memphis  Sand (Figure 10),      of
the Flour Island/Tuscahoma (Figure 11), and
base of Fort Pillow/Nanafalia (Figure 12). The
major faults identified by Csontos et al. (2008)
are also shown  on the maps. Although the
interpolation algorithm in ArcGIS is applied to
an irregular field of data, the resulting output
is given as a rectangular region bounded by
the longitudinal  and latitudinal extents of each
    set.  Interpretations, however, are limited
only to the data-constrained regions of the
maps. Interpolation schemes for all points
are described in Tables App2 and App3
Appendix Geophysical Logs). The location (x,y)
numerical rank for lines, polygons and
were recorded in the feature class' metadata.
For point data, the location (x,y) numerical rank
and elevation (z) qualification were stored as
attributes for each feature.

The      of the Cook Mountain Formation
is shown in Figure 7.  Overall, this surface
is highest along the eastern side of the ME
and is lower in the central southern ME in
eastern Arkansas, although few data points
constrain the latter trend. The irregular slope
of the surface      of the Mississippi River
with low      in Panola (MS), DeSoto (MS),
Lauderdale (TN), and Obion (TN) counties has
been interpreted by Hundt (2008) to be due
to pre-Cook Mountain fluvial erosion; whereas
Martin (2008) favors the influence of a series
of east-west fault-bounded grabens for the
apparent structural lows. Given the limited
     borehole     from which to constrain
Martin's proposed fault-bounded structures and
the overall lower elevation of the      of the
Cook Mountain Formation from     to west,
the fluvial-erosion interpretation        most
supported at present

The      of the Kosciusko/Sparta/upper
Memphis Sand is shown in Figure 8. The
upper Memphis Sand in northeastern Arkansas
and western Tennessee is the correlative upper
sand interval to the Kosciusko (MS) and Sparta
sands (MS) identified on the cross-sections
(Plates 1-5). This surface is highest along the
eastern side of the ME, but also shows high
      along the western central part of the ME
that follow Reelfoot Rift-bounding faults defined
by Csontos (2008). The surface is highly irreg-
ular,  but generally slopes to the south.  Similar
to the      of the Cook Mountain Formation,
prominent lows are present in Panola (MS),
DeSoto (MS), Lauderdale (TN), and Obion (TN)
counties; however, lows are also observed in
several       of Arkansas as well.

The      of the Tallahatta/Cane River/middle
Memphis Sand is show in Figure 9. Again,
the middle Memphis Sand interval is shown
in cross-sections in eastern Arkansas and
western Tennessee (Plates 1-5). The surface
is highest along the eastern side of the ME,
but highs are also observed along the western
     of the ME and trending east-west in Cross
(AR), Crittenden  (AR), and Shelby (TN) coun-
ties.  The latter high               the surface
into two structural basins, one centered in
Mississippi (AR), Lauderdale  (TN), and Tipton
(TN) counties,  and the other centered in the
southern central  ME.  Several of the structural
basin boundaries appear to follow major faults
within the northern ME.

The      of the Meridian/Carrizo/Memphis
Sand is shown in Figure 10. The surface
structure generally follows that of the ME, with
western margin of the structural basin closely
following  the central SW-NE fault within the
northern  ME.  The       of both the Flour
Island/Tuscahoma (Figure 11) and Fort Pillow/
Nanafalia (Figure 12) show structural trends
nearly identical to that in Figure 10. However,
the extent of the  Fort Pillow Sand in the north-
ern ME is poorly constrained  by the available
data.

-------
                    91°0'0"W
          90°0'0"W
   36°0'0"N-
   35°0'0"N
                                    ^mM
                                                               h Ben,.    T
                                    t,"                   Mar*all
                                    -'  Tunica       Tate
                                                     -36°0'0"N
                                                      3500'0"N
                    91°0'0"W
          90°0'0"W
89°0'0"W
                                                                   Base of Cook Mountain
                                                                   Elevation (MSL)
                                                                         High : 470
Legend
  •   Well control
|      Major rivers
|     | Geologic investigative extent
\^/^\ Crowley's Ridge
     J Northern Mississippi embayment ^^| Low : -420
      County                     Topography (USGS 30m)
	State                       Elevation (MSL)
                                       High : 2,250
                 i                     I
                20     40            80 Miles

                                       Low : 50
Figure 7.    Structure contour map of the base of the Cook Mountain Formation in the study area. Elevations
            are in feet.

-------
                        91°0'0"W
   36°0'0"N-
                      Gibson    1     |-36°0'0"N
                              Canon
   35°0'0"N
           Howell   Oregon          Ripley   ^    Butter
                     ...
                                   35°0'0"N
                        9rO'0"W                 90°0'0"W
                     Legend
                      •   Well control
                          Major faults
                     |    | Major rivers
                     |    | Geologic investigative extent
                     Y///\ Crowley's Ridge
                  89°0'0"W
Base of Kosciusko Fm./Sparta Sand/
upper Memphis Sand
Elevation (MSL)
^^ High : 350

      Low: -636
                         J Northern Mississippi embayment Topography (USGS 30m)
                    I      County                      Elevation (MSL)
                    	State                             High : 2,250
          I       i       |              i
          0      20     40            80 Miles

      Low : 50
Figure 8.    Structure contour map of the base of the Kosciusko Fm./Sparta Sand/upper Memphis Sand in the
            study area. Elevations are in feet. Major faults are from Csontos et al. (2008).

-------
                        91°0'0"W
                                    89°0'0"W
   36°0'0"N
   35°0'0"N
                            o:
       i^jiidi
                                                         Valobusha     Ca(hour,
             -36°0'0"N
                                               3-35°0'0"N
                                             Alcorn
                        91°0'0"W
                   Legend
                    •   Well control
                        Major faults
                   |    | Major rivers
           90°0'0"W
89°0'0"W
             Base of Tallahatta Fm./Cane River/
             middle Memphis Sand
             Elevation (MSL)
                   High : 305
                  |     | Geologic investigative extent
                  Y///\ Crowley's Ridge              ^^| Low : -1486
                  [_	] Northern Mississippi embayment Topography (USGS 30m)
                       j County                     Elevation (MSL)
                        State                             High : 2,250
                20      40
80 Miles
                                                         Low : 50
Figure 9.    Structure contour map of the base of the Tallahatta Fm./Cane River Fm./middle Memphis Sand in
            the study area. Elevations are in feet. Major faults are from Csontos et al. (2008).

-------
                        91°0'0"W
                                        90°0'0"W
                                                        89°010"W
   36°0'0"N
   35°0'0"N
                                                    DeSolo              L
                                                               MarAall
                                                    <               L
                                                                              -36°0'0"N
                                                                            3-35°0'0"N
                                                                          Alcorn
      91°0'0"W
Legend
  •   Well control
      Major faults
	  Major rivers
|     | Geologic investigative extent
Y////\ Crowley's Ridge
                                                 90°0'0"W
                                                                 89°0'0"W
                                                   Base of Meridian Sand/Carrizo Sand/
                                                   lower Memphis Sand
                                                   Elevation (MSL)
                                                         High : 550

                                                         Low:-1666
                  j	__J Northern Mississippi embayment Topography (USGS 30m)
                  	 County                     Elevation (MSL)
                  	State                             High : 2,250
I        i       \
0      20     40
                                       \
                                      80 Miles
                                       Low : 50
Figure 10.   Structure contour map of the base of the Meridian Sand/Carrizo Sand/lower Memphis Sand in the
            study area. Elevations are in feet. Major faults are from Csontos et al. (2008).

-------
                        91°0'0"W
           90°0'0"W
                          89°0'0"W
   36°0'0"N- "">
   35°0'0"N
                                                   36°0'0"N
                                                3-35°0'0"N
                                              Alcorn
                        91°0'0"W
           90°0'0"W
                                                                           8900'0"W
                Legend
                  •   Weil control                   Base of Flour Island/Tuscahoma Fm.
                      Major faults                   Elevation (MSL)
                |      Major rivers                         High : 518
                |     | Geologic investigative extent
                Y///^ Crowley's Ridge               j^B  Low : -2146
                i__ ._j Northern Mississippi embayment Topography (USGS 30m)
                I      County                      Elevation (MSL)
                	 State                              High : 2,250
          I
          0       20      40
 I
80 Miles
_
      Low : 50
Figure 11.   Structure contour map of the base of the Flour Island/Tuscahoma formations in the study area.
            Elevations are in feet. Major faults are from Csontos et al. (2008).

-------
                      91 °0'0"W
90°0'0"W
   i
   36°0'0"N-
   35D0'0"N
                                          -36°0'0"N
                                                                                        — -35°0'0"N
                      91 °0'0"W
                   Legend
                     •   Well control
                         Major faults
                   |     | Major rivers
90°0'0"W
89°0'0"W
     Base of Fort Pillow/Nanafalia Fm.
     Value
           High : 452
                   |     | Geologic investigative extent
                   Y////\ Crowley's Ridge               ^^j Low : -2366
                   j_    J Northern Mississippi embayment Topography (USGS 30m)
                   I      County                      Elevation (MSL)
                   	State                              High : 2,250
             I       i        i               I
             0       20      40             80 Miles
     _
           Low: 50
Figure 12.    Structure contour map of the base of the Fort Pillow Sand/Nanafalia Fm. in the study area. Eleva-
             tions are in feet. Major faults are from Csontos et al. (2008).

-------
Discussion
Lithostratigraphic correlation and uncertainty
The proposed stratigraphic correlations in
the northern ME (Table 4) are reasonably
constrained by cross-sections and surface
maps presented in this study and surfaces
presented in Hart et al. (2008). However,
some of the correlations, especially at the
Tennessee-Mississippi state line are tenuous
and difficult to reconcile.  For example, the
sandy Hatchetigbee Fm. in northern Mississippi
appears to laterally grade into the finer grained
Flour Island in the central ME, but what is their
contact relationship and how does it relate
regionally with the overlying Claiborne Group?
A similar type of question could be applied to
the basal Wilcox as well.  Although parsimoni-
ous,  the correlation of the Old Breastworks
Formations with the Naheola Formation is
somewhat speculative and lacks regional
paleontological basis.  More detailed correlation
with geologic and paleontologic control needs
to  be completed before many of these ques-
tions can be addressed.

Another approach to evaluating stratigraphic
consistency is to examine the trend of bound-
ing surfaces (i.e., base or top of formations).
The presence of sharp or irregular changes in
surface elevation may suggest either structural
truncation or inconsistent formation picks,
which create sharp and erratic breaks in the
surface or high error in the surfaces. The IDW
interpolation scheme employed by ArcGIS 9.3

Table 5.  Surface interpolation statistics.
provides statistical basis for evaluating errors
in the surface interpolation. The results from
the surfaces created are shown in Table 5. The
nearest neighbor ratio approaches values of
one for random distributions of evenly spaced
data.  Values less than one indicate clustering
and those greater than one indicate dispersed,
distant data. Most of the nearest neighbor
values are slightly less than or slightly more
than one, except for the base of the Jackson,
Hatchetigbee and Porters Creek surfaces.  The
nearest neighbor results indicate reasonable
but slightly clustered data distributions for the
surfaces shown in Figures 7 through  12. In
general, values of the Z-scores far from 1 and
low values of p (probability) indicate the surface
is not a random collection of data. Probabilities
less than 95% confidence (p > 0.05) or
Z-scores close to 1 are observed for the base
of the loess, Fort Pillow and Old Breastworks
surfaces, suggesting the potential for random
distribution and low significance. The optimized
polynomial fit was determined using the IDW
algorithm in ArcGIS 9.3. The sensitivity of
the surface to changes in polynomial  fit were
addressed by adding and subtracting 1  from
the polynomial degree. The optimized polyno-
mial minimized the RMS (root mean square)
error.  The RMS error evaluates the error in
grid and map coordinate transformations in
the interpolation process; lower values indicate
better point control and lower uncertainty. The
highest RMS errors are observed  for  the base
of the Hatchetigbee and Old Breastworks
surfaces, suggesting poor control  on these
Surface
Number of Records
Nearest Neighbor Ratio
Z-Score (Std Dev)
P-Value
Optimized polynomial fit
(-1)
RMS(-l)
mean error
Optimized polynomial fit
RMS
mean error
Optimized polynomial fit
(+D
RMS (-H)
mean error
Base
Loess
23
1.115
1.058
0.290
2.41
44.73
-10.70
3.46
43.70
-11.15
4.46
44.23
-10.53
Base
Alluvium
56
0.828
-2.460
0.014
2.39
72.95
-7.54
3.39
72.07
-7.06
4.39
72.58
-6.80
Base
Jackson
10
1.725
4.388
0.000
3.48
59.67
-4.99
4.48
58.70
-1.35
5.48
58.95
0.43
Base
Cockfield
51
0.814
-2.547
0.011
1.00
95.87
1.12
1.38
95.10
-0.94
2.38
97.87
-4.95
Base
Cook Mtn
81
0.695
-5.249
0.000
1.00
110.40
2.42
1.50
108.00
1.98
2.50
112.20
-1.80
Base
Kosiciusko
74
0.683
-5.224
0.000
1.39
129.30
0.87
2.39
125.40
3.06
3.39
127.10
4.34
Base
Zilpha
45
1.168
2.159
0.031
1.29
139.40
21.61
2.29
136.20
16.06
3.29
138.30
10.56
Base
Tallahatta
66
0.870
-2.016
0.044
3.18
181.10
9.53
4.18
180.50
9.71
5.18
181.00
9.53
Base
Meridian
76
0.812
-3.143
0.002
2.92
180.70
9.35
3.92
179.20
11.62
4.92
179.20
11.62
Base
Hatchetigbee
10
1.790
4.781
0.000
1.66
391.60
-19.20
2.66
384.20
-31.57
3.66
388.80
-40.54
Base Flour
Island
63
0.867
-2.021
0.043
4.48
179.30
10.59
5.48
178.40
9.04
6.48
179.00
7.86
Base Ft.
Pillow
41
0.865
-1.653
0.098
9.21
184.80
15.20
10.21
184.60
15.60
11.21
184.80
15.93
Base Old
Breastworks
20
1.138
1.181
0.238
30.62
446.70
-92.70
31.62
446.70
-92.77
32.62
446.70
-92.83
Base
Porters
Creek
7
2.166
5.904
0.000
-1.00





1.00


 RMS - Root Mean Square error

-------
surfaces. Although the statistical results for the
major formation and intraformational surfaces
are adequate (Figures 7-12), they are far from
ideal. Additional data in more evenly spaced
distributions are desirable for each of the
surfaces shown.

Hydrostratigraphy
The results from this study clarify the extent
of hydrostratigraphic units defined in previ-
ous studies (Criner and Parks, 1976; Hosman
and Weiss, 1991; Brahana and Broshears,
2001; Hart and Clark, 2008; Hart et al.,  2008),
and constrain the quality of the regional
aquifers based on lithologic information.
High-production aquifers are considered to be
those composed almost exclusively of sand
in thicknesses of 100 ft or more.  Examples
include the Fort Pillow and Memphis aquifers
in western Tennessee (Parks and Carmichael,
1989; 1990a).  Low- to moderate-production
aquifers are considered to be those composed
of mixtures of sand, silt, and clay beds,  with
sand intervals being less than 100 ft thick and
discontinuous. An example is the Cockfield
aquifer of western Tennessee (Parks and
Carmichael, 1990b).  Confining units in the
study area are generally dominated by silt
and clay with thin (generally less than 20 ft
thick), discontinuous sand  beds.  Confinement
is hydraulically defined, however, to provide
confining pressure to underlying aquifers; thus,
any lithologic classification of confinement must
be further constrained by hydraulic data. For
example, the Flour Island Formation appears to
be an effective confining unit in the central ME
based on lithology as well as the lateral extent
of pumping cones of depression and low stor-
age coefficients in the underlying Fort Pillow
aquifer (Parks and Carmichael, 1989).

Regional hydrostratigraphic units are presented
in Table 4 and associated surface maps were
produced by (Hart et al., 2008). Our results
generally confirm the extents of hydrostrati-
graphic  units from Hosman and Weiss (1991),
Brahana and Broshears (2001), and Hart
et al. (2008); however, the lithologic results
suggest that the quality and characteristics of
each aquifer change over the study area.  For
example, the Fort Pillow-Lower Wilcox aquifer
are mapped throughout the region by Hart et al.
(2008), but fine-grained deposits dominate the
Nanafalia Formation (Fort Pillow equivalent) in
much of northern Mississippi (Plates 6 and 7)
and the Wilcox Formation in the outcrop region
of western Tennessee (Russell and Parks,
1975) (Plate 2). These observations along
with trends in development of the Fort Pillow
and Lower Wilcox aquifers within the central
ME (Parks and Carmichael, 1989; Arthur and
Taylor, 1998) indicate that the Fort Pillow-Lower
Wilcox aquifer has much less regional extent
than that illustrated by Hart  et al. (2008).  In
regard to the Lower and  Middle Claiborne-
Memphis aquifer, fine-grained intervals cor-
relative to the Basic City and Zilpha shales
exist throughout the study area (Plates 1-7)
suggesting that the Memphis aquifer is better
considered as three separate subaquifers. This
assertion is supported by tritium and other
hydrologic tracer data that indicate the upper,
middle, and lower sand intervals within the
Memphis aquifer have limited vertical hydraulic
connectivity (Larsen et al., 2005; Gentry et al.,
2006). The Cockfield Formation in the north-
ern ME locally contains several thick (> 100
ft) sand intervals (Plates 1 and 2) (Parks and
Carmichael, 1990b); however, these sands are
not laterally continuous and may have limited
potential for development.

The lithologic data also suggest that the
degree of confinement provided by several
of the confining units changes over the study
area.  The Cook Mountain Formation within
the upper Claiborne confining unit contains
discontinuous sand intervals, which may
provide pathways for leakage into the upper
part of the Memphis aquifer in the Memphis
area (Parks, 1990; Arthur and Taylor, 1998;
Brahana and Broshears, 2001). The basal
surface of the Cook Mountain is highly irregular
with a deeper section in the south-central ME
(Figure 7).  This surface bears similarities to
that of the Kosciusko/Sparta/upper Memphis
Sand (Figure 8),  but otherwise does not
conform to the shape of underlying surfaces
(Figures 9-12). These observations sug-
gest that extensive fluvial erosion occurred
prior to and following deposition of the upper
Memphis Sand interval (rather than localized

-------
growth faults: Martin, 2008), which may further
contribute to variations in the thickness and
stratigraphy of confining silts and clays in the
upper Claiborne confining unit. Persistent sand
intervals are also observed in the Flour Island
Formation in eastern Arkansas (Plates 2, 4, 5,
6, and 7) and the Old Breastworks Formation in
the northern ME (Plate 1).

        Structure
The results of the present study generally sup-
port the structural interpretations of the north-
ern ME by Kingsbury and Parks (1988), Parrish
and Van Arsdaie (2004), Stevens (2007),
Csontos et al. (2008), and Martin (2008).  Many
of the faults mapped by Csontos  et al, (2008)
show clear offsets in the Tertiary  stratigraphy.
Martin (2008) also mapped several SW-NE
trending regional faults, which are consistent
with offsets in northern Mississippi and western
Tennessee.  However, E-W trending grabens
described by Martin (2008) based on his
surface interpolation of the Memphis Sand are
interpreted to be erosional rather structural
features.

The amount of offset of Tertiary strata along
faults in the study area is generally less than
100 ft, although offsets of several hundred feet
are suggested along some regional structures.
Determining the amount of fault offset based
on geophysical  logs is difficult and requires
closely spaced well-correlated log sections.
Most offsets of Tertiary strata in the study area
are less than 100 ft  and are difficult to constrain
based on the distance between logs.  However,
offsets of several hundred feet are observed
along the margins of Crowley's Ridge (Plate 2),
the northern extent of the Southeast margin
rift fault (Cox  et al., 2006) (Plate 1), and along
another SW-NE trending structure in northern
Mississippi (Plate  7). Confirmation of signifi-
cant fault offsets within the Tertiary stratigraphy
confirms the potential for vertical  inter-aquifer
water transfer suggested by Kingsbury and
Parks (1993).


The review of the literature and analysis of
existing geological and geophysical (borehole)
data indicates general continuity of regional
lithostratigraphic units throughout the study
area in the central and northern Mississippi
Embayment (ME). The stratigraphic terminol-
ogy and units are correlated amongst the three
states in the study area (Arkansas, Mississippi,
and Tennessee), although some revisions
of nomenclature and regional  interpretation
are necessary.  Our analysis suggests that
the Old Breastworks Formation  of the Wilcox
Group in the northern ME is correlated to the
IMaheola Formation  of the Midway Group in
Mississippi (as suggested by Frederiksen et
al.,  1982); however,  further paleontological
work is required to confirm this parsimonious
correlation. The Hatchetigbee Formation of
Mississippi likely correlates to the  lowermost
part of the Memphis Sand in Tennessee,
although it is unclear whether the  Hatchetigbee
pinches out at the state line or is amalgamated
into the lower Memphis Sand. The tripartite
division of the lower and Middle Claiborne
Group defined in Arkansas (Carrizo Sand,
Cane River Formation, and Sparta Sand) is
mappable over the three state region and pro-
vides a useful subdivision of the Memphis Sand
in the northern ME.  Two regionally observed
fine-grained intervals in the Memphis Sand
correlate to the Basic City Shale (member of
the Tallahatta Formation)  and  Zilpha Shale
in central Mississippi and shales near the
base and top of the  Cane River Formation
in Arkansas. The lower Memphis  Sand is
essentially equivalent (allowing for some sand
equivalent to the Hatchetigbee Formation at the
base) to the Meridian Sand in Mississippi and
Carrizo Sand in Arkansas. The  upper Memphis
Sand is equivalent to the  Kosciusko Sand in
Mississippi and Sparta Sand in Arkansas.

The lithostratigraphic correlation and internal
lithological variations in the formations within
the study area have implications for the hydro-
stratigraphy. Lithological variations in the Fort
Pillow Sand and Nanafalia Formation from
thick clean  sand intervals in the central ME
to mixtures of sand, silt, and clay in western
Tennessee and northwestern  Mississippi indi-
cate that the Fort Pillow-Lower Wilcox aquifer is
not as extensive as  has been  mapped by other
studies (Hosman and Weiss, 1991; Hart et al.,

-------
2008), The Middle Wilcox aquifer, which mainly
comprises the Hatchetigbee Formation, is of
limited extent in the study area and may be
equivalent to the lower Memphis aquifer except
in northern Mississippi,  Regional continuity of
fine-grained intervals correlative to the Basic
City and Zilpha shales in Mississippi and
other  hydrologic information indicate that the
Memphis aquifer (Lower and Middle Claiborne
aquifer) may be better represented as three
subaquifers, with the lower Claiborne confining
unit correlating to an interval of discontinu-
ous aquifers between the regional Lower and
Middle Claiborne aquifers.  Confinement of the
Fort Pillow-Lower Wilcox aquifer is provided
by fine-grained intervals of the Flour Island
Formation and equivalent  strata in northern
Mississippi throughout most of the study area.
The Upper Claiborne confining unit contains
sandy intervals and is partially removed by late
Cenozoic erosion in the central and eastern
ME, which limits confinement of the Memphis
(Middle Claiborne) aquifer in part of the study
area.  The Upper Claiborne aquifer has limited
preserved extent in the study area and  is com-
prised of discontinuous sand intervals within
the Cockfield Formation.

Faults offset the Tertiary strata throughout the
study area, but most offsets are estimated to
be less than 100 ft in dip-slip throw.  Several
regional faults show evidence of greater
amounts  of dip-slip offset, including faults
bounding Crowley's Ridge, and faults defining
the southeastern margin of the ancient  Reelfoot
rift. The latter structures have the potential to
influence regional groundwater flow, but all of
the faults have potential for inter-aquifer water
transfer.


Many of the correlation problems discussed
above and the overall limited quality of surface
reconstruction from the available data can be
addressed by completing several specific data
objectives listed below.

Correlation of geologic and hydrostratigraphic
unit in the study area  is limited by the number
of reference sections available.  For example,
the Fort Pillow (Moore and Brown, 1969)
and New Madrid test wells (Frederiksen et
al., 1982) provide detailed stratigraphic and
paleontological control required for correla-
tion.  However, no such reference boreholes
exist in northern Mississippi, southwestern
Tennesseee, and eastern Arkansas.  A well-
constrained correlation of the strata in the
northern and central ME cannot be completed
without this data. Furthermore, the core and
cuttings returned from the reference boreholes
could more clearly define the compositional,
permeability, and porosity characteristics for the
hydrostratigraphic units. These data are neces-
sary for accurate groundwater flow modeling
within the region.

The data set compiled for this project was
admittedly  incomplete and the visualization and
computational  tools applied were readily avail-
able  software.  Acquisition of additional high-
quality borehole data and utilization of state-of-
the-art geospatial imaging tools, such as those
used in the petroleum industry (e.g., Landmark,
Petrel, etc.), are needed to develop an accurate
three-dimensional hydrostratigraphic model for
the study area. The geophysical logs need to
be scanned, digitized, and scaled properly to
obtain the maximum benefit, and the resulting
digital data needs to be projected in fully three-
dimension  imaging software.  Fortunately, the
Ground Water  Institute has acquired additional
log datasets and the necessary equipment,
software, and  expertise to begin the process of
transforming the existing data into a common
digital format.

Borehole data  provide point observations of
vertical stratigraphic relationships; however,
all lateral relationships between data points
need to be inferred  using stratigraphic and
structural principles. A true test of strati-
graphic and structural relationships can best
be made using seismic reflection analysis
of the central and northern ME. Multiple
seismic lines have been completed within the
ME; however,  most  of these lines emphasize
either the very shallow structure (e.g., Cox et
al., 2001a;  Williams et al.,  2001) or the deep
crustal structure (e.g., Parrish and Van Arsdale,
2004).  Seismic reflection data focused on the
Tertiary stratigraphy along the trough of the

-------
ME as well as across the ME are needed to
test the stratigraphic concepts developed in
this and other regional studies (e.g., Hosman
and Weiss, 1991; Hosrnan, 1996; Hart et al.,
2008). Water-based seismic reflection surveys
of the Mississippi River channel and underlying
stratigraphy recently completed by Magnani et
al. (2008) provide a good starting point for this
work; however, land-based seismic surveys
across the ME are also needed.

                 quality          and

Ground water quality is a high priority in the
central and northern Mississippi embay-
ment (ME) in the tri-state area of Tennessee,
Mississippi and Arkansas.  Threats to water
quality in the region  include nutrients, pesti-
cides, and herbicides from agricultural runoff,
industrial pollution, urban runoff, and legacy
contamination from past waste disposal
practices (Graham, 1982; Parks, 1990;  Kleiss
et al., 2000; Gonthier, 2000; Gonthier, 2002).
The main usage of ground water in the region
is irrigation (Holland, 2007) due to the fact
that much of the land is used for agriculture.
However, urban growth in the tri-state area
of Mississippi, Arkansas, and Tennessee has
increased the usage of ground water (Webbers,
2000; Holland, 2007), mainly to meet demands
for drinking water and industrial supplies.

Past studies of water quality in the Tertiary
and Quaternary aquifers within the northern
and central ME have established the overall
high quality of ground water and regional
trends in hydrochemistry (Wells, 1933; Criner
and Armstrong, 1958; Bell and Nyman, 1968;
Boswell  et al., 1965; 1968; Payne, 1968;
1972; 1975; Brahana et al., 1987; Pettyohn,
1996).  More recent studies have focused
on potential for contamination  or degradation
in water quality in agricultural (Kleiss et al.,
2000), municipal, and industrial water supplies
(Parks et al., 1981; Graham and Parks, 1986;
Parks, 1990; Bradley, 1991; Parks and Mirecki,
1992; Parks et al. 1995; Larsen et al., 2003;
Gentry et al., 2005; Ivey et al.  2008). Declines
in the potentiometric surfaces  of regional
aquifers (Criner and  Parks, 1976; Kingsbury,
1996; Schrader, 2008a) create the potential for
vertical leakage of poor quality or contaminated
waters from surface and shallow ground water
sources, especially in areas where regional
confining units may be thin or missing (Graham
and Parks, 1986; Parks, 1990).

In this study hydrogeochemical data were
obtained from historical records to statistically
analyze variations and groupings in water qual-
ity, and prepare contour maps of geochemical
constituents to identify spatial controls on
water quality.  These observations date from
the late 1920s to the mid 2000s, and vary in
regard to completeness and quality of chemical
analysis.  To place the water quality variations
in a regional context, data were collected and
analyzed from wells throughout the ME and into
the Gulf Coast region. This analysis allowed
assessment of large-scale  influences, such
as physiographic region, fault systems, and
basin-scale groundwater flow, on water quality.
The data were obtained from wells screened in
four aquifers: Quaternary Alluvial (Mississippi
River and  tributary alluvium), Upper Claiborne
(Cockfield Formation and equivalents), Middle
Claiborne (Kosciusko Formation,  Memphis
Sand, and Sparta Sand), and Lower Claiborne-
Wilcox (Cane River Formation, Carrizo Sand,
Meridian Sand, Hatchetigbee Formation,
and Fort Pillow Sand) (Hosman and Weiss,
1991; Brahana and Broshears, 2001). The
analysis focuses on seven  counties in the
central and northern ME: Shelby County (TN),
Tipton County (TN), Hardeman County (TN),
Fayette County (TN), Crittenden County (AR),
DeSoto County (MS), Benton County (MS),
and Marshall County (MS). However, statistical
analysis and mapping  incorporated a greater
region including much of the central and
northern ME. Pettyohn (1996) conducted a
similar analysis of water quality data in the ME
and Gulf Coast; however, our effort focuses on
a smaller geographic region and the water data
are grouped differently. The land use in the
investigated area includes urban land use in
the Memphis metropolitan area and agricultural
use in the surrounding areas. The objectives
for assessing the water quality are to:

-------
 1. Catalog water chemistry variables from
    disparate datasets.  Query the USGS,
    EPA, state environmental agencies,
    and published research literature for
    chemical data available for ground water
    and surface water in the region. The
    goal is to collate data within a database
    to allow for assessment of spatial and
    temporal variability in ground-water
    chemistry.

 2. Ascertain temporal ground water
    quality changes and chart statistical
    variation among measured geochemical
    variables. Filter the cataloged water
    quality data for accuracy,  classify based
    on water quality characteristics, and
    evaluate trends and data  groupings
    using statistical models.

 3. Conduct a spatial assessment of
    contamination threats to the ground
    water and ascertain chemical signatures
    and environmental tracers valuable
    for numerical model calibration and
    analytical modeling. Identify the spatial
    distribution of threats and data gaps
    through time  series assessments
    of specific constituents. Identify
    environmental tracers that have
    potential application in evaluating
    ground-water flow paths and rates of
    recharge, especially with regard to
    potential threats.

Catalog water chemistry variables from
disparate datasets
We assembled ground-water and surface-
water quality data from a variety of sources
(e.g.,  USGS, publications, and unpublished
reports as well as from federal, state and local
agencies, Native American tribes, volunteers,
academics and others). These data are pre-
sented in electronic form within the supple-
mentary documentation of this report. The
USGS data were obtained from the National
Water Information System (NWIS; Earthlnfo
Inc, 2005). Surface water data were organized
by stations, analysis and observation (Table 6,
Figures 13-17).  Although surface water data
were identified and cataloged, no hydrochemi-
cal analysis  was completed  on those data.
Ground water data were organized by stations,
analysis and observation. Each station was
connected to data for state,  hydrogeologic unit,
county, analysis (pH, DOC, etc.) and observa-
tion (time and datum value;  Figures 18-20).
Sample site  distributions within aquifer units are
shown in the appendices.
Table 6.   Surface water database contents.
State
Arkansas
Mississippi


Tennessee



TOTAL
Station
1182
1478


1554



4214
County
Crittenden
Marshall
DeSoto
Tunica
Fayette
Hardeman
Tipton
Shelby

Stations per
county
8
9
8
4
6
9
7
42
93
Observations
3899
234
706
109
11496
5947
10352
31225
63968
Analyses
167
16
29
8
1185
302
1377
3294
6378

-------
        45



        35
     o  ?  20
        10
/
                       n
UH
                                          3500

                                          3000

                                          2500
                                                  1000
                                                         //
                                                                    n


Figure 13.   Stations and Analyses within surface water database.
               Crittenden  Marshall    DeSoto
                                   Tunica
                   Fayette   Hardeman   Tipton
Shelby
Figure 14.   Number of observations by county in surface water database.

-------
   -34 5   -94   -515   -S3   -92 5  -52  -51 5   -91   -90 5   -80
Figure 15.    Map of surface water station loca-
              tions in AR.  Pink stations shown in
              Crittenden county. Database contains
              observations 1911-2003.
                                                         34,5-
                                                          34-
                                                         33.B-
                                                          33-
                                                         32-6^
                                                          32-
                                                         31.5-
31-
                                                         30.5-
                                                             -91.8    -91    -90.5
                                                                                       -83.8
                                                         Figure 16.    Map of surface water station locations
                                                                       in Mississippi. Database contains
                                                                       observations 1911-2003 for Marshall,
                                                                       DeSoto and Tunica counties.
                    -90      -89
                                      -88
                                             .-' -. .•  "•,* • . ';..  '"  --^ '-*,.. ;4i .,'.-..•" f'-'~y-~'-'--,
                                             '}~'.\ -^r".•&'•:-,}-.  ..•'.- ->'"-i '}•-. ;''
                                              r.  r --^  ."•.-. ..-vr.'.-^ •..•>"
Figure 17.   Map of surface water station locations in Tennessee.  Database contains observations 1911-2003
              for Fayette, Hardeman, Tipton and Shelby counties.

-------
                                     v*w
                                          "~  *
                 34-
Figure 18.   Map of ground water station locations in AR. Pink stations shown in Crittenden County,
            Mississippi,  Database contains observations 1911-2003,
                       345-
                        34*
                       33.5-
                        31 i-
                       305
                                                        :'

Figure 19.   Map of ground water station locations in Mississippi. Database contains observations 1911-2003
            for Marshall, DeSoto and Tunica counties, Mississippi.

-------
             35^=
-90
                        -89
-88
                         -8?
-86
-88
-84
-83
-82
Figure 20.   Map of ground water station locations in Tennessee. Database contains observations 1911-2003
            for Fayette, Hardeman, Tipton and Shelby counties.  Note that stations (blue crosses) that are
            identified as Shelby county actually plot in AR,
         and

From an analytical perspective, the ground
water quality data were, at times, inaccurate
or incomplete. Consistency in the analyses
between boreholes and across time was lack-
ing.  We found that some samples for which
there were sufficient data were not electrically
neutral  (an inequality between sum of anions
and  cations in milligram equivalents per liter
or meq/L). We therefore used AquaChem 5.0
(Waterloo Hydrologic, Inc, 2005) to compute
missing values of some major ions in those
samples that were otherwise complete in terms
of parameters of interest.

Accuracy of the chemical analyses was esti-
mated by calculating the electrical neutrality
(E.N.; Figure 21) (Eq. 1).
Equation 1:
=  (Sum C - Sum A)
   (Sum C + Sum A)
                                   100
where A is individual anion species (meq/l) and
C is individual cation species (meq/l). If E.N.
is greater than or equal to 2% (absolute value),
then the accuracy of the data for that sample is
considered good. E.N. values between 2 and
5% (absolute value) are considered acceptable.
Samples with values in excess of 5% were
removed from the data set. Approximately 20%
of the data were eliminated because of E.N.
greater  than 5%. The main factors reducing the
accuracy of chemical analyses are absence
of two and more anions or cations and poor
                 quality of analytical measurements. Accuracy
                 of geochemical data for the Quaternary Aquifer
                 Complex is presented in Figure 21.

                 Hydrochernical classifications of the ground
                 water based on the filtered geochemical data
                 were performed using AquaChem following the
                 Piper, Durov and Wilcox methods. AquaChem
                 was used to determine the water type using
                 a trilinear Piper diagram (Kehew, 2001).
                 Hydrogeochemical maps were constructed
                 using Surfer 7.0 (Golden Software, Inc.,
                 1999). Shape maps for Arkansas, Tennessee,
                 Mississippi and Louisiana were downloaded
                 from the U.S. Census  Bureau. In Surfer 7.0,
                 the grid size was 87 rows and 100 columns;
                 the contour of hydrostratigraphic units was
                 approximated by option breaklines, which were
                 digitized using geological maps; the fault option
                 was used to delineate the influence  of the
                 Mississippi River.  Inverse Distance to a Power
                 was used for data interpolation. Surfer 7.0 also
                 was used to display and separately analyze
                 well locations for states and aquifers.

                 For each aquifer unit we performed both
                 univariate and multivariate statistical analysis of
                 the data used  SPSS statistical software (SPSS,
                 2000). Univariate analyses were limited to
                 descriptive statistics, linear (Pearson's) correla-
                 tion coefficients, histogram and  box and whis-
                 ker plots, as well as detection of anomalous
                 chemical concentrations. Pearson's correlation
                 coefficients (r) are  considered significant when
                 greater than or equal to 0.5. The coefficient
                 of determination (R2) would then be greater
                 than 0.25 or 25%, expressing the proportion of
                 data with a significant value of r (Rock, 1988).
                 Cluster analysis used  the hierarchical option

-------
Bin
-5.09
-4.64
-4.20
-3.76
-332
-2.88
-2,43
-1.99
-1.55
-1.11
-0.67
-0.22
0.22
O.S6
1.10
1.54
1.99
2.43
2.8?
3.31
3.75
4.20
4.64
More

1
13
12
14
11
9
18
22
32
56
52
71
44
41
28
20
16
23
16
20
19
8
10
8
ft
17.73%
2.48%
4.61%
7.09%
9.04%
10.64%
13.83%
17.73%
23.40%
33.33%
42.55%
55,14%
62.94%
70,21%
75.18%
78.72%
81.56%
85.64%
88,48%
92.02%
95.39%
96.81%
98.58%
100,00%

80 -, 	
70 -
60 -
| 50 -
| 40 -
Ģ. 30 -
20 -
10 -
0 -

: a




|JL
lfl+ltitlA
Oli.WtO-^O0"*"'
gMWgWOT^og
EM bin
— ;^r-ŧT- 100%
9'

llll :
j%11.li.%14
- 80%
- 60% |
- 40% i
o
- 20%
- 0%
K> 00 .k.
CO ~J CB
•~4 Ol A

6.00

4.00

2.00 -

0.00

•2.00 J

4.00
                                       •6.00
                                             -:/'.--'-ioa'''-
           .'ado-.
'•Ŧ.-
".fno>
                                                                               MO
                                                        number of samples
 Figure 21.   Data filtered and outliers (E. N. > 5% removed). ALVM is the Mississippi Alluvial Valley aquifer
            complex.
and dendrogram graphical representation
with average linkage between groups.  We
also employed squared Euclidean distance
with Z scores standardization when exploring
geochemical groupings. Factorial analysis used
principal components without rotation.  We ana-
lyzed the correlation matrix, unrotated  factor
solution and scree plots to identify the two or
three most significant factors contributing to the
variance in the data.

Throughout the available data sets, few ground
water quality time series and limited monitoring
data exist. These data are important to under-
stand temporal and spatial water chemistry
changes and allow us to map data from differ-
ent time periods.  For example, early studies in
the Memphis area argued that the water-quality
impacts of ground water extraction are minor
in the area (Bell  and Nyman, 1968; Graham,
1982).   However, more recent studies have
shown progressive declines in water quality,
especially around pumping centers (Parks
et al., 1995; Larsen et al., 2003; Gentry et
al., 2005) and waste disposal sites (Parks,
1990; Bradley, 1991; Parks and Mirecki, 1992;
Mirecki and Parks, 1994; Gentry et al., 2006).
Two groups of monitoring data were used: a)
continuous monitoring data for one well and
b) monitoring data for  a suite of neighboring
wells. The use of multiple neighboring wells
is justified because the wells are screened in
the same hydrostratigraphic unit, the distance
between the wells was approximately 1  to 5
km, and the values of monitored parameters
were in the same statistical range.  Inclusion
of both single well  and closely spaced wells
from the same hydrogeologic unit extended the
temporal range of the  monitoring investigations.
Both single monitoring well and well-suite time
series were approximated  by polynomial trends
of an  order of more than two terms of equation.

-------
Results
Water quality characteristics of the Quaternary
Alluvial aquifer
The Quaternary Alluvial aquifer includes well
locations from mainly the Mississippi Valley
Alluvial aquifer as well as additional data points
from alluvial aquifers associated with tributaries
in the region (Figure 22). Most water-quality
threats  to regional municipal and industrial
water supplies exist from surface or shallow
ground  water recharge to deeper aquifers
(Graham, 1982; Parks, 1990; Parks et al., 1995;
Kleiss et al.,  2000; Gonthier, 2000; Gonthier,
2002); hence, water quality evaluation of the
Quaternary Alluvial aquifer serves to better
identify locations where such threats exist.
Because few recent evaluations of water quality
monitoring data in the Quaternary Alluvial
aquifer  exist we checked our assumption that
aquifer  data from different time periods were
statistically the same  and could be used to
characterize  regional  geochemical properties of
the aquifer complex.  Changes in chloride (Cl~)
and electric conductivity (EC) over time are not
significant, similar to results from other studies
(Kresse and  Clark,  2008). For Cl~, variations are
within several mg/L to 20 mg/L. EC variation
             falls between 0.1-0.2 mS/cm. In spite of high
             human impact in the central ME, time variations
             of CI" and EC are not significant and are char-
             acteristic of natural unperturbed water quality
             conditions in the aquifer. Because the aquifer
             data from different time periods can charac-
             terize regional geochemical properties (e.g.,
             Moraru and Anderson, 2005), the compiled
             shallow ground water data from the Quaternary
             Alluvial aquifer were  used for detailed analysis
             of regional water quality trends.

             Ground water  levels in the Quaternary Alluvial
             aquifer fluctuate over time. Statistical trends
             reveal that water levels are generally decreas-
             ing, with water level declines of 10 to 66 ft.
             Similar results have been observed from other
             studies in the Mississippi Alluvial aquifer (Reed,
             2004; Arthur, 2001) and the shallow aquifer
             system (alluvial and fluvial-terrace deposits)
             in the Memphis metropolitan area (Parks,
             1990). The average ground water level decline
             is approximately 33 ft, and such changes are
             characteristic only for specific regions within
             the central ME (i.e., near multiple wells used for
             irrigation). Nevertheless, such changes in water
             level and consequently in water storage do not
             appear to affect water quality drastically.
           30-
                          -92
-90
-88
-85
-84
-82
Figure 22.   Well locations in the Quaternary Alluvial aquifer.

-------
Analyses of descriptive statistics (Table 7)
indicate that some of the data are non-normal.
Normal sample distributions have similar values
of mean, median, and mode, as well as skew-
ness (coarse- or fine-tailing) of 0,0 and kurtosis
(peakedness) of approximately 3. Deviations
in mean and median from mode may result
if many values near the detection limit  are
observed, as is the case for trace metal
analysis. Deviations from normal distributions
are also indicated by standard deviation values
exceeding the  mean values, dominance of
positive skew, and kurtosis values much greater
than 3. Therefore, for most of the parameters
listed in Table 7 the  statistical relevance of the
mean values is low.  In cases where values of
the coefficient  of variation are greater than or
equal to 1.0, mean values are statistically most
useful (i.e., K+, Na+,  SO42~, CI-, AI3+, As(total),
Fe(total), Mn2+, NH4+, Ni+, NO3- + NO2-, Pb
and Zn2+).
                                      2+

-------
Table 7.    Descriptive statistical parameters for ground water of the Quaternary Middle Mississippi
           Embayment (n.d. is non-detect).
Parameter,
units
K, mg/l
Na,mg/l
Ca, mg/l
Mg,mg/l
HCO3, mg/l
S04, mg/l
Cl, mg/l
Ag,mg/l
Al,mg/l
As, mg/l
Ba,mg/l
Be,mg/l
Cd,mg/l
Co,mg/l
C org., mg/l
Cr,mg/l
Cu,mg/l
F,mg/l
Fe(ll),mg/l
Fe,mg/l
Mn,mg/l
Mo, mg/l
NH4,mg/l
Ni,mg/l
NO3+NO2,mg/l
Pb,mg/l
Se,mg/l
Si,mg/l
U,mg/l
Zn,mg/l
TDS,mg/l
pH
NO2,mg/l
02,mg/l
Temperature.C
Tritium, piC/l
EC, uS/cm
N
455
555
562
569
556
549
554
185
109
173
144
76
134
60
11
143
128
312
12
362
219
55
53
53
106
85
107
333
15
151
553
534
59
12
515
26
537
Minimum
0.08
2
0.3
0.1
7
0
0.1
0.001
0
0.001
0
0.001
0
0.001
1
0
0
0
0.6
0
0
0.001
0.01
0.001
0
0
0
2.4
0.001
0
41
5.2
0
0.1
11
1
7
Maximum
41
140
153
84
814
130
190
0.003
1
0.033
1.3
0.002
0.008
0.015
2
0.01
0.01
1.1
7.6
31
4.3
0.01
11
0.023
11
0.02
0.006
51
0.001
0.27
948
8.8
0.07
0.3
27.2
32
1,620
Mean
3.450
23.530
62.606
19.773
305.980
18.288
21.950
0.001
0.110
0.005
0.319
0.001
0.002
0.004
1.580
0.005
0.004
0.190
4.278
3.505
0.736
0.007
0.971
0.005
0.630
0.003
0.001
25.902
0.001
0.020
337.270
7.095
0.016
0.125
17.639
10.230
539.440
Std.
Deviation
5.260
23.998
35.422
12.467
162.840
23.648
35.565
0.000
0.218
0.005
0.265
0.000
0.002
0.004
0.440
0.004
0.004
0.135
2.353
5.533
0.781
0.004
2.033
0.006
1.764
0.004
0.001
9.043
0.000
0.038
169.701
0.623
0.013
0.062
2.160
9.705
289.417
Coefficient
of
variation
1.525
1.020
0.566
0.630
0.532
1.293
1.620
0.175
1.981
1.176
0.832
0.376
0.896
0.880
0.278
0.738
0.975
0.710
0.550
1.579
1.061
0.657
2.094
1.083
2.802
1.643
0.815
0.349
n.d.
1.946
0.503
0.088
0.835
0.498
0.122
0.949
0.537
Skewness
4.618
2.348
0.191
1.115
0.352
2.365
2.881
9.168
2.379
2.438
1.288
0.991
1.967
0.962
-0.015
0.362
0.476
2.207
0.135
2.079
1.953
-0.454
3.781
1.29
3.944
2.519
3.532
-0.148
n.d.
4.818
0.961
-0.146
2.068
2.555
1.427
1.001
0.883
Kurtosis
23.461
6.369
-0.639
2.759
-0.074
5.960
8.264
90.190
5.111
7.413
1.535
-0.282
3.729
-0.371
-1.518
-1.434
-1.741
10.776
-1.145
4.644
4.831
-1.828
14.573
0.597
16.594
6.216
19.071
-0.542
n.d.
26.287
1.241
0.084
5.074
6.242
4.494
-0.060
1.274

-------
Analysis of the correlation matrix for elements
illustrates several geochemical associations.
Characteristic correlations between IDS, EC,
dissolved O2, and most major cations and
anions are observed. Sodium and chloride are
strongly correlated, but show no correlations to
other constituents.  Calcium (Ca), magnesium
(Mg), barium (Ba), and bicarbonate (HCO3) are
all positively correlated, suggesting a common
source from dissolved carbonate minerals.
Conversely, Cobalt (Co) and Molybdenum
(Mo) are negatively correlated to Ca, Mg, Ba,
and HCO3, suggesting different affinities for
these elements. Among the trace elements,
correlations are commonly observed  among
the siderophile ("iron-loving") and chalcophile
("sulfide-loving") trace elements, such as chro-
mium (Cr),copper (Cu), and cobalt (Co), lead
(Pb), and selenium (Se). Strangely, all  of these
elements show either no correlation or  a signifi-
cant negative correlation to total iron  (Fe) and
ferrous iron (Fe2+).  The latter relationship may
reflect the strong dependence of iron solubility
on oxidation-reduction conditions rather than
source relationships.

The Piper diagram and scatter plots (Figure 23)
reveal key hydrochemical water types found in
the Quaternary Alluvial aquifer and their rela-
tionship to water-rock interaction.  Bicarbonate
(HCO3) is the dominant anion and  Ca,  Mg,
and sodium (Na), respectively, are  the most
important cations (Figure 23A and  B).  Average
anion and cation compositions of the individual
hydrochemical water types are plotted versus
TDS in Figures 23C and D.  Both anions and
cations show systematic changes with  increas-
ing TDS that are likely due to a combination
of progressive water-rock interaction with the
aquifer minerals and mixing of surface waters
and shallow groundwater. The HCO3~ water
type is  transformed with increasing TDS to
slV^v/^ -O\_/ , j F"l\_<'\_/_  \_/J  ->3\_/ , i i!v_'\_/Ŧ  \_slf ->3 \_/ ,
HCO3 and Cl -HCO3, in succession (Figure
23C). For example, bicarbonate water becomes
HCO3-SO4 atTDS^SOO mg/L and CI-HCO3
atTDSŦ900 rng/L The cation values display
large variations as well. Overall, calcium (Ca2+)
is the dominant cation at TDS < 700 mg/L
(Figure 23D). Calcium (Ca2+) contents  are
roughly constant in waters with TDSŦ700 mg/L,
presumably due to buffering by calcium carbon-
ate equilibrium. Above TDSŦ700 mg/L sodium
(Na+) becomes dominant most likely due to
influence of vertical recharge of saline fluids
from underlying aquifers (Bryant et al., 1985;
Kresse and Clark, 2008).  Despite variations in
calcium and  sodium abundance, the rnolar Mg/
Ca ratio ranges from 0.29 to 0.40, with an aver-
age of 0.34.  This ratio is consistent with a com-
bination of carbonate mineral sources, such as
calcite (CaCO3) and dolomite (CaMg(CO3)2).

Contour maps of aqueous species concen-
trations and TDS, EC and hydrochemical
water type illustrate the spatial variations in
water compositions. The bicarbonate water
type is most common throughout the central
Mississippi embayment, with subordinate
regions of HCO3-CI and HCO3-SO4 water types
along the Arkansas River valley (northern fine
dashed line) as well as other locations along
the margins of the Mississippi Alluvial valley
(Figure 24).  The TDS map shows the highest
values along the traces of the Mississippi and
Arkansas rivers as well as regions of intense
groundwater pumping, such as in western-cen-
tral Mississippi and eastern-central Arkansas
(Figure 25).   Low TDS values (<400 mg/L)
are characteristic for elevated territories;
high TDS values (>400 mg/L) are generally
located in the river valleys (Mississippi, White,
Arkansas and other rivers) and in the Memphis
urban area.  Although TDS values for stream
waters are generally elevated above values
in  local recharge (Kresse and Clark, 2008),
the hydrologic influence of the major streams
(Mississippi, Arkansas, and White rivers)
diminishes within a couple miles of the stream
bank (Ackerman, 1996; Arthur,  2001). Also,
high TDS is common for some irrigated regions,
where pumping stresses may be inducing
intrusion of deeper saline waters (Bryant et
al., 1985). Neither water type nor TDS map
distributions  show relationships to the major
structural features in the ME, suggesting little
or  no fault control of discharge. The maps for
IMa+, Ca2+, Mg2+, HCO3-, Cr and Ba2+ all show
similar characteristics to the water type and
TDS maps; however, the map for Fe (Figure 26)
shows generally low values within the center
of  the Mississippi Alluvial valley with higher

-------
                                                                       SO4
  D
*/\*
                     .
                   '

          type
    so-----.
          No   / \
        ' dominint "   \
          type   Sodhŧ\
    Caldoro       lypeoc \
     ivpe             \
          c
         Cations
         /   \ demiiant /

        ' tiartoniB ^  r' CMowfe


               ~'§


                a
                                                                             400     600

                                                                              IDS, mg/l
                                                                                            800     1000
                                                               0.0      200,41     400.0     600,0
Figure 23.   A) Piper diagram for hydrochemical classification of water compositions in the Mississippi Alluvial
             aquifer. B)  Classification of hydrochemical water types (from Kehew, 2001).  Anion (C) and cat-
             ion (D) contents versus total dissolved solids (TDS) shown with trend lines: (C) - dots and discon-
             tinuous line are Cl, squares and line are /-/CO,",  triangles and discontinuous line-dots are SO42~;
             (D) dots and discontinuous line are Ca2", squares and line are A/a', triangles and discontinuous
             line-dots are Mg"1.

-------
               36
                                                        Hydfogcochcmic.il wattr types
                                                        In the Mississippi River valley
                                                               alluvial aquifer
                                                        Explanation: water types defined
                                                            by predominant anlon
                               -92
                                          -90
                                      -88
               cmcoj

Reelfoot Rift

Alabama-Oklahoma transform

Arkansas and Saline River F Z

Pickens-Gilbertown F.Z.

 -86         -84         -82
Figure 24.   Map showing distribution of hydrogeochemical water types in the Quaternary Alluvial aquifer, cen-
             tral Mississippi Embayment (county boundaries are shown). Reelfoot Rift from Schweig and Van
             Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991). Arkansas and Saline River
             fault zones from Cox et al. (2006).  Pickens-Gilbertown Fault Zone from Bicker (1969).
                                                      Explanation: TDS vahm *e in ing I
                                                              Reelfoot Rift

                                                              Alabama-Oklahoma transform

                                                              Arkansas and Saline River F.Z.

                                                              Pickens-Gilbertown F.Z.
30-
                                                                           -84
                                                                       -B2
Figure 25.   Map showing TDS distribution, Quaternary Alluvial aquifer, central Mississippi Embayment (county
             boundaries are shown). Reelfoot Rift from Schweig and Van Arsdale (1996). Alabama-Oklahoma
             transform from Thomas (1991). Arkansas and Saline River fault zones from Cox et al. (2006).
             Pickens-Gilbertown Fault Zone from Bicker (1969).

-------
                                                     Total Iron (Ft) dlatrtbutlon
                                                        alluvia aqirffw
                                                   Explanation; F* valuta an in ugn
                                                   rn
                                                      m  era  mo  ion  am
                                                        Reelfoot Rift
                                               — — —  Alabama-Oklahoma transform
                                               	  Arkansas and Saline River F.Z
                                                	  Pickens-Gilbertown F.Z
30-
                 -84
Figure 26.   Map showing the dissolved Fe distribution, Quaternary Alluvial aquifer, central Mississippi
            Embayment (county boundaries are shown). Reelfoot Rift from Schweig and Van Arsdale (1996).
            Alabama-Oklahoma transform from Thomas (1991). Arkansas and Saline River fault zones from
            Cox et al. (2006). Pickens-Gilbertown Fault Zone from Bicker (1969).
concentrations mainly along the eastern margin
and more erratic locations along the western
margin. Thus, iron appears to be associated
with recharge along the valley margins and
likely oxidation-reduction gradients.

Geochemical associations were further evalu-
ated using cluster and principal component
analysis. Three clusters, or groups, were identi-
fied on the hierarchical dendrogram (Figure 27)
and component analysis (Figure 28). The first
group suggests that Fe(total) and Mn(total)
have the same origin in shallow ground water,
most likely dissolution of dispersed Fe-Mn
minerals that were formed during geological
deposition and post-depositional weathering
reaction of Quaternary sediments in the region,
especially along the margins of the Mississippi
Alluvial valley. The second group combines
SO42-, K+, Cl- and Na+. This geochemical
association is based on the most soluble salts
in ground water. The strong association of Na
and Cl may have complex origins, ranging from
migration of saline ground waters from depth
(Bryant et al., 1985) to infiltration of evaporated
irrigation and stream waters (Kresse and Clark,
2008). The third cluster aggregates pH, HCO3-,
Ca2+, Mg2+, EC and TDS. HCCy, Ca2+ and
                                     Mg2+ form one common sub-cluster because
                                     of their dependence on carbonate equilibrium
                                     and dissolution of carbonate minerals. TDS
                                     and EC functionally depend on each other as
                                     well and are shown to be strongly correlated
                                     in Mississippi Alluvial aquifer waters (Arthur,
                                     2001).  The pH is linked to this cluster as the
                                     geochemistry of Ca-Mg-HCO3 is controlled by
                                     the values of hydrogen ion activity and PC02
                                     (e.g., Drever, 1997).

                                     Water quality in the Quaternary Alluvial aquifer
                                     in the central ME limits the types of water use.
                                     Groundwater in the Alluvial Aquifer is used
                                     extensively for irrigation (Ackerman, 1996;
                                     Arthur, 2001) and much less for domestic water
                                     supplies.  Although all salinity hazard catego-
                                     ries are encountered in the Mississippi Alluvial
                                     Aquifer, the hazard is generally low or medium.
                                     The sodium  hazard is nearly always low with
                                     only few isolated cases of medium and  high
                                     values. In practice, municipal water use is gen-
                                     erally limited due to high iron concentrations
                                     and hardness (sum of Ca and Mg). Analysis of
                                     the Fe  map (Figure 26) shows that all studied
                                     regions have concentrations at or above the
                                     US EPA secondary drinking water standards
                                     maximum level (Fe = 0.3 mg/L). In addition,

-------
                                      Heacaled, Distance Cluster Combine
CASE 0
TDS 8 — r 	
&C 10 -J

HCvJ1 5 _-___-.- _ ,.
fltt t mmmmmmmmm

f,h 7 ^^^^^

^Tftri R


s









10








I 1










15
3


2





Ģ0










a







h
23









Figure 27.   Hierarchical dendrogram of the geochemical clusters for Quaternary Alluvial aquifer. Line a-b is
            the value ofrescaled distance equal to 20, which mark clusters; 1, 2 and 3 are geochemical clus-
            ters shown in Figure 36.
approximately 10% of the analyses have values
that exceed US EPA primary drinking water
standards for barium (Ba), fluoride (F~), or
nitrate (NO3-).
Component 2
        0.0
        Component 1
                             -.5
                                        1.0
                     o.o
                     Component 3
Figure 28.   Component plot of the factorial
            analysis, Quaternary Alluvial aquifer
            (ph is pH, hco3 - HCO3, ca -
mg -
                      ec - EC, tds - TDS, so(4)
            - SO/, na - Na+, cl - Cl, k - K\ mn -
            Mn(total) and fe - Fe(total); 1, 2 and 3
            are geochemical associations).
Water quality characteristics of the Upper
Claiborne aquifer
The Upper Claiborne aquifer comprises sand
intervals within the Cockfield Formation and, to
a lesser extent, adjacent sand intervals in the
underlying Cook Mountain Formation (Hosman
and Weiss, 1991). The aquifer is used  most
extensively in western Tennessee and in the
south-central ME, as illustrated by the distribu-
tion of wells screened in the aquifer (Figure 29).

Time-plots of dissolved constituents in  samples
from groups of closely spaced wells screened
in the Upper Claiborne aquifer show no consis-
tent trends.  Concentration variations from sam-
pling event to event typically exceed the range
of values observed in long-term trends. For
example, Figure 30 shows trends in Ca2+ and
TDS in individual and several groups of closely
spaced wells.  The values of Ca2+ commonly
vary more between individual sampling events
than the variations modeled by the polynomial
trend lines.

Descriptive statistics for the analyses from the
Upper Claiborne aquifer are given in Table 8.
The values of the standard  deviation are of
similar magnitude or exceed the  values of
the mean, indicating most parameters have

-------
non-normal distributions.  Almost all of the
parameters are positively skewed, indicating
the presence of a tail of larger (outlier) values.
Only temperature, which has limited deviation,
and pH, which is a log-transformed unit, show
negative skew.  Most of the data show kurtosis
values between 0 and 5, indicating only
moderate deviation from normal distributions;
however, Cl, F, Mn, NO3, and PO4 all show
much higher values of kurtosis associated with
highly peaked distributions.

Correlation analysis shows that several param-
eters show significant correlations, beyond
expected correlations with specific conduc-
tance, IDS, and major constituents (e.g., Ca
and Mg, HCO3 and pH, etc.). The most sig-
nificant correlations exist amongst (1) sodium,
bicarbonate, chlorine, boron, and fluorine, and
(2) barium, calcium, magnesium, and bicarbon-
ate. The first grouping appears to reflect a
sea-water  association, as all of these constitu-
ents are concentrated in sea water, whereas
the second is most likely from a carbonate
mineral source, similar to that described for the
Quaternary Alluvial aquifer.

The Piper  diagram in Figure 31A reveals sev-
eral geochemical trends in water composition
in the Upper Claiborne aquifer. In general, the
upper diamond  plot shows complete  scatter,
suggesting an absence of strong cation-
anion associations.  However, the trilinear
cation (Figure 31A) plot shows a mixing trend
between Ca-Mg waters with strongly Na+K
waters.  The ratio of Mg/Ca ranges from 0.1
to 1.5, with most values following a value of
0.6. The anion trilinear diagram (Figure 31A)
and histogram (Figure 31B) illustrate that
most waters are dominated by  bicarbonate
and sulfate with lesser amounts of chloride;
however, a limited number of samples also is
rich in chloride and bicarbonate with  little or no
sulfate.  The association of chloride with more
concentrated waters is illustrated in Figure 32,
which further confirms the presence of a saline,
alkaline component identified in the correlation
analysis.

Trends in water chemistry are further  clarified
in the contour map distribution  hydrochemical
water types in Figure 33.  The water type
observed throughout most of the study area
in the Upper Claiborne aquifer is bicarbon-
ate (HCO3), much like that observed in the
Quaternary Alluvial aquifer. However, a north-
west-southeast trending region of chloride- and
sulfate-bearing bicarbonate waters follows
the regional trend of the Oklahoma-Alabama
transform fault (Thomas, 1991), which is a zone
of tectonic weakness and prone to Quaternary
seismicity (Cox et ai., 2004; Cox et ai., 2006).
Furthermore,  the chloride- and sulfate-bearing
bicarbonate waters fall within two regional fault
zones, the Saline and Arkansas River fault
zones (Cox et al., 2006) in Arkansas and the
Pickens-Gilbertown fault zones (Bicker, 1969) in
Mississippi. No obvious recharge or discharge
features in the Upper Claiborne aquifer in
Arkansas correlate to the water quality changes
(Schrader, 2008b).  The southern margin of
the Pickens-Gilbertown fault zone marks the
northern extent of Jurassic salt domes in the
Gulf Coast (Ewing, 1991); however, no salt
domes are known to exist in the southeastern
Arkansas area. Chloride- and sulfate-bearing
bicarbonate waters are also observed in the
south-central  part of the ME and are likely
related to fluid-flow associated with salt domes
or up-dip flow from the Gulf Coast (Hanor and
Mclntosh, 2007, Mclntosh et al., 2009).

The distribution of wells with high TDS waters
(Figure 34) also follows the general trends
identified in the hydrochemical water type
diagram, especially for the wells in southeast-
ern Arkansas. Lower TDS waters are generally
in upland recharge areas, such as those in
western Tennessee, south-central Arkansas,
and central Mississippi. More localized regions
of high TDS are observed in the Memphis area
and central Arkansas where extensive pumping
may be causing water quality changes.  In con-
trast, the contour map of bicarbonate (HCO3)
values (Figure 35) shows overall increases in
central Arkansas and in the southern part of
the study area where saline Gulf Coast basin
waters are migrating up-dip along aquifer units
(Hanor and Mclntosh, 2007). Thus, the higher
TDS and chloride content waters north of the
Gulf Coast basin appear to have a distinctive
spatial association.

-------
Figure 29.
                36-
                34-
                32-
                30-
      -94          -92          -90         -88         -86         -84

Well locations in the upper Claiborne aquifer within the study area.
                                                                                              -82
                                                             B
       -94  -93   -92  -91
                                         -85  -34  -83
       100.00
       80.00
       60.00
       40.00 -
       20.00
        0.00
           Ca,ing/l
          Ca
                   TDS
Monitoring well 2
 TDS,mg/l
     1000.00
     800.00
     600.00
   •  400.00
     200.00
     0.00
             3   is
             n   si
                 fe  3?  ^  S
                                                                  Ca,ing/l
                                                                                   Monitoring well 1
                                                                                     TDS, mg/l
                                                                                          1600
                                                                                     CO  (D (D CO  <Ģ>
                                                                                     CO  CO 
-------
Table 8.   Descriptive statistical parameters for ground water of the Upper Claiborne aquifer in the central and
          northern Mississippi embayment
Parameter
Al,ug/l
B,ug/l
Ba,ug/l
Ca,mg/l
Cl,mg/l
C02,mg/l
Cond., Us
F,mg/l
Fe,ug/l
HCO3,mg/l
K,mg/l
Mg,mg/l
Mn,ug/l
Na,mg/l
NO,,mg/l
pH, units
P04,mg/l
Si,mg/l
SO4,mg/l
TDS,mg/l
Temp.,Celsius
Zn,ug/l
N
55
51
28
715
1116
412
908
585
494
674
616
727
208
677
484
824
55
550
794
793
577
28
Range
2700
2.39
400
90
1099.8
53
3295
8.4
3000
572
10.9
42
1600
785.9
10
6.2
7.5
46
220
2053
16
140
Minimum
0
0.01
0
0
0.2
0
25
0
0
0
0.1
0
0
1.1
0
2.9
0
0
0
27
11
0
Maximum
2700
2.4
400
90
1100
53
3320
8.4
3000
572
11
42
1600
787
10
9.1
7.5
46
220
2080
27
140
Mean
611
0.49
153.25
15.48
78.31
10.74
741.01
0.5
446.3
245.61
2.97
5.61
114.1
122.86
1.11
7.55
0.93
18.82
23.87
446.78
20.75
30.86
Standard
Deviation
729.7
0.56
105.2
20.51
147.4
13.32
564.94
0.8
671.94
150.25
2.01
8.11
175.72
111.77
1.67
0.97
1.54
9.55
40.69
316.39
2.31
41.25
Variance
532465.89
0.32
11066.64
420.71
21727.43
177.44
319158.44
0.64
451498.96
22575.5
4.04
65.7
30877.09
12491.85
2.78
0.93
2.38
91.26
1655.37
100101.53
5.33
1701.68
Skewness
1.36
1.54
0.8
1.67
3.62
1.55
1.84
4.69
2.07
0.17
1.41
1.96
4.77
1.87
3.07
-1.45
3.05
0.69
2.7
1.91
-0.26
1.57
Kurtosis
1.01
2
0.21
2.01
14.71
1.45
4.24
30.13
3.63
-0.78
2.36
3.46
33.51
5.15
11.81
3.24
10.73
0.2
7.94
4.55
1.1
1.35
Anomaly
> 2715
> 2.9
> 560
> 96
> 1152
> 53
> 3360
> 8.3
> 3000
> 571
> 11
> 47
> 5577
> 847
> 10
> 8.7
> 2.5
> 46
> 220
> 2263
> 27
> 164
Cluster and principal component analysis were
used to independently verify water quality
relationships identified through spatial and
correlation analysis, and further explore geo-
chemical processes. Hierarchical dendrogram
and principal component analysis yield three
geochemical associations (Figures 36 and 37),
similar to those observed in the Mississippi
Alluvial aquifer. However, association 1  shows
linkage between NaCI, the carbonate system,
temperature and TDS/Specific Conductance,
suggesting contributions from a more alkaline,
saline water source potentially at depth. This
component likely integrates the spatially distinct
high-TDS, chloride-rich waters identified in
Figures 33 and 34.  Potassium and sulfate
appear to be associated as salt components,
perhaps from specific recharge or Gulf Coast
sources.  Ca,  Mg, Mn, and Fe are all associ-
ated, either from various carbonate minerals or
a combination of carbonate minerals and redox
processes affecting Mn and Fe oxides and
hydroxides.  No obvious spatial relationships
are apparent among these quantities.

Water in the Upper Claiborne aquifer  in the ME
is generally of higher quality than that of the
Quaternary Alluvial aquifer, except in  regions
where high-TDS, chloride- and sulfate-rich
waters are observed (see Figures 33  and 34).
Groundwater in the Upper Claiborne aquifer
is used sparingly for industrial,  municipal, and
domestic supplies in western Tennessee (Parks
and Carmichael, 1990b), but is used more
extensively in Arkansas (Holland, 2007) and
Mississippi (Wasson, 1980). All salinity and
sodium hazard categories are encountered
(Figure 38), with most samples low to high
sodium hazard and medium to  high salinity
hazard.  Approximately 2%  of the analyses
have values that exceed US EPA primary

-------
                                                                   SO4
_ Water Type Upper Claibome
D
400 -i
j/2
'S 9nn
E
n -






*s




\
PI , f^hrr^T— r-m . , ŧ
- 100
-80 
-------
                 36-
                                                        Watar types distribution in the UppŦr Claibomo aquifer


                                                        LMNMI
                                                                Reelfoot Rift

                                                       _ _ _  Alabama-Oklahoma transfomi

                                                                Arkansas and Saline River F.Z

                                                                Pickens-Gilbertown F.Z.

                                                                  -86
                                                                                        -82
Figure 33.    Distribution of major water types in the Upper Claiborne aquifer. Reelfoot Rift from Schweig and
              Van Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991). Arkansas and Saline
              River fault zones from Cox et al. (2006).  Pickens-Gilbertown Fault Zone from Bicker (1969).
                                                      Total di**olv*d ŧolldŧ (TDS) In ttw Uppar Cltlbonw Mulfai
                                                       explanation: TDS values are In mg/l
                                                                Reelfoot Rift

                                                       — — _  Alabama-Oklahoma transform

                                                                Arkansas and Saline River F Z

                                                                Pickens-Gilbertown F.Z
30-
                                 -92
                                            -90
                                                       -88
                                                                  -86
                                                                             -84
                                                                                        -82
Figure 34.    Contour map of total dissolved solids (TDS) in the Upper Claiborne aquifer.  Reelfoot Rift from
              Schweig and Van Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991). Arkansas
              and Saline River fault zones from Cox et al. (2006). Pickens-Gilbertown Fault Zone from Bicker
              (1969).

-------
                36-
                                                           Bicarbonate (HCO3) distribution
                                                           in thŦ Upper Cl
                                                           Explanation! HCO3 values ara In mg/1
                                 Reelfoot Rift

                                 Alabama-Oklahoma transform

                                 Arkansas and Saline River F.Z

                                 Pickens-Gilbertown F.Z,
                                -92
-90
-88
-86
-84
-82
Figure 35.    Contour map of bicarbonate (HCO3) in the Upper Claiborne aquifer. Reelfoot Rift from Schweig
              and Van Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991).  Arkansas and
              Saline River fault zones from Cox et al. (2006). Pickens-Gilbertown Fault Zone from Bicker
              (1969).
                   Dendrogram using Average Linkage  (Between Groups)

                                          Rescaled Distance Cluster Combine
CASE 0



N3 ^






Mg A 	
Pft Q
|

























1C












1












11










-

I _








2


3
25












Figure 36.   Hierarchical dendrogram of the geochemical associations for Upper Claiborne aquifer.  Line a-b
             is the value of reseated distance equal to 20, which mark clusters; 1, 2 and 3 are geochemical
             clusters shown in Figure 37.

-------
Figure 37.   Component plot of the factorial analysis Upper Claiborne aquifer (HCO3 - HCO3, Ca - Ca2\ Mg
            - McK Cond -specific conductance, SO4 - SO/, A/a - A/a+, Cl - Cl, K - K\ Mn - Mn(total) and
            Fe - Fe(total); 7, 2 and 3 are geochemical associations).
                                              1000

                                      Salinity Hazard (Cond)
Figure 38.   Wilcox diagram illustrating degree of sodium and salinity hazards in the Upper Claiborne aquifer.
drinking water standards for fluoride (F~) or
nitrate (NO3~). All studied regions have con-
centrations at or above the US EPA secondary
drinking water standards maximum level for
iron (Fe = 0.3 mg/L).

Water quality characteristics of the Middle
Claiborne aquifer
The Middle Claiborne aquifer comprises sand
intervals within the Sparta Sand in southeast-
ern Arkansas, Kosciusko Sand in Mississippi,
and Memphis Sand in northeastern Arkansas
and western Tennessee (Hosman and Weiss,
1991). Because the Memphis Sand includes
stratigraphic equivalents to both the middle
and lower Claiborne aquifers (see section on
Hydrostratigraphy), water quality assessment
in Middle Claiborne aquifer is complicated by
inclusion of multiple stratigraphic units that may
or may not be hydrogeologically connected.
Because the Memphis Sand is relatively
shallow in the central and  northern ME, water

-------
quality characteristics are likely to follow those
of the middle rather than lower Claiborne inter-
val. The aquifer is used extensively in western
Tennessee and in the south-central ME, as
illustrated  by the distribution of wells screened
in the aquifer (Figure 39).

Time-plots of dissolved constituents in samples
from groups of closely spaced wells screened
in the Middle Claiborne aquifer show no con-
sistent trends. Concentration variations from
sampling event to event typically exceed the
range of values observed in long-term trends.
For example, Figure 40A shows trends in Ca2+
and TDS in a well in Sparta aquifer in Arkansas
(Figure 41).  The values of both TDS and
Ca2+ commonly vary more between individual
sampling events than the variations modeled
by the linear trend lines. Several  studies in the
Memphis area have demonstrated localized
water quality changes in the upper Memphis
aquifer (Parks and Mirecki, 1992; Parks et al.,
1995; Larsen et al., 2003); however, these
reports have investigated wells in the vicinity of
either production well fields or waste disposal
sites.

Descriptive statistics for the analyses from the
Middle Claiborne aquifer are given in Table 9.
The values of the standard deviation are of
similar magnitude or exceed the values of
the mean, indicating most parameters have
non-normal distributions.  Almost all of the
parameters are positively skewed, indicat-
ing the presence of a tail  of larger (outlier)
values.  High variance is commonly associated
with large anomalous values.  Only dissolved
oxygen that has limited deviation, and pH
that is a log-transformed unit show negative
skew. Approximately half of the measured
parameters show kurtosis values between 0
and 10, indicating only moderate deviation from
normal distributions; however, Br, Cl, B.C., Fe,
K, Mg, Mn, Na, NO3, SO4 and Sr all show much
higher values of kurtosis associated with highly
peaked distributions.

Correlation analysis shows that amongst the
specific conductance, TDS,  and major con-
stituents the most prominent correlations are
between pH, TDS, EC, Na, Cl and HCO3. Of
the minor  and trace constituents, F, I, Br, and
B show significant correlations to Na and/or K
and Cl.  Iodine also shows strong correlation
to SO4, Mn, Sr, and B.  These correlations
appear to  reflect a sea-water association or
that of alkaline brine derived from seawater.

The Piper diagram in Figure 42 reveals sev-
eral geochemical trends in water composition
             36-
             34-
             32-
             30-
                  -94        -92       -90        -88        -86        -84

Figure 39.   Well locations in the Middle Claiborne aquifer within the study area.

-------
                                                                                SPRT-5
Ca,mg/l TDS,mg/l
10 n "cn
8.0 -
6.0 -
4.0
2.0 -
n n -
Ca -
' ' * TDS
I I I
- 120
- 90
60
- 30
- n
                           CDCDCDCDCDCDCDO
                           O)    *N|    ^"'J    OQ    oo    co    co    1*1
                           COCJlCDCOOOCOCDJti.
                                             Year
                 B
                                                                                   WQ6
Ca,mg/l
-inn
8.0 -
6.0 -
.0
2.0
On .






TDS,mg/l
Hen
TDS
^ ^ *








Ca


K1

K>

- 120
- 90
60
30
n
K.1
                            (DCDCDCDCDCDCOCDCDCDOOO
                                gCDCDCDCDCDCOCDCDCDOOO
                                ->-K)CO.fc.CnC>->ICDCDO->-K)

                                                 Year




Figure 40.   A) Ca2^ and TDS data from 1968 to 2004 for monitoring well 1304 (Figure 41) in the Sparta Sand.

             B) Ca2+ and TDS data from 1990 to 2002 for monitoring well Sh:K-66 in the upper Memphis Sand.
                36
                30
                                -92
                                          -90
                                                     -88
                                                               -86
                                                                          -84
                                                                                    -82
Figure 41.     Locations of monitoring wells in the Middle Claiborne aquifer used for time-series plots of water

             quality.

-------
Table 9.     Descriptive statistical parameters for ground water of the Middle Claiborne aquifer in the central and
            northern Mississippi embayment.
Parameter
Al,ug/l
B,ug/l
Ba,ug/l
Br,mg/l
Ca,mg/l
Cl,mg/l
C02,mg/l
E.C.,uS/cm
F,mg/l
Fe,ug/l
HCO3,mg/l
l,mg/l
K,mg/l
Mg,mg/l
Mn,ug/l
Na,mg/l
N03,mg/l
02,mg/l
pH
Si,mg/l
SO4,mg/l
Sr,mg/l
TDS,mg/l
Temp.,Celsius
Zn,ug/l
N
305
94
376
77
1093
1087
330
1030
924
752
1097
34
1033
1092
526
1088
349
71
1041
1007
1079
217
990
918
255
Range
4
4

8
87
860
97
3713
0.9
27
838
8
29.9
84
2
774
17
7
5
72
93
3
984
32

Remark: n.d. - no data
Minimum
0
0

0
0
0
0
7
0
0
0
0
0.1
0
0
1
0
0
4
0
0
0
16
6


Maximum
4
4

8
87
860
97
3720
0.9
27
838
8
30
84
2
775
17
7
9
72
93
3
1000
38


Mean
0.3
0.27

0.16
12.389
16.623
11.15
299.21
0.151
1.09
152.48
0.85
2.232
4.554
0.01
48.73
0.97
1.99
7.03
15.65
5.92
0.1
168.96
20.17


Standard
Deviation
0.71
0.83

0.93
14.13
62.32
15.11
345.45
0.14
2.31
131.8
2.27
2.58
5.71
0.12
78.65
1.88
2.13
0.99
8.98
8.35
0.38
144.23
4.1


Variance
0.5
0.69

0.87
199.77
3883.32
228.28
119338.62
0.02
5.35
17370.8
5.16
6.66
32.61
0.01
6185.76
3.54
4.53
0.98
80.59
69.74
0.15
20801.73
16.83


Skewness
2.83
3.13

8.07
2.19
8.96
2.4
4.68
2.4
4.11
1.56
2.68
4.06
3.94
13.55
3.82
5.48
0.71
0.34
2.63
4.99
4.48
1.99
1.52


Kurtosis
8.35
8.71

68.12
5.36
94.28
6.59
32.81
7.68
26.64
2.69
5.94
27.78
36.56
201.17
21.85
37.54
-0.86
-0.91
9.31
36.43
22.94
5.14
2.49


Anomaly
>4
>4
n.d.
>8
>100
>1000
>100
>4000
>1
>30
>850
>8
>30
>100
>2
>1000
>20
>7
>9
>100
>100
>3
>1000
>38
n.d.

                                                Piper Plot
Figure 42.    Piper diagram for water chemistry data from the Middle Claiborne aquifer. See Figure 12B for clas-
              sification fields.

-------
in the Middle Claiborne aquifer. The upper
diamond plot shows that most of the waters are
bicarbonate-rich with either Ca+Mg or Na + K
cation compositions; however a variety of other
water types are present as well.  The trilinear
cation (Figure 31A) plot shows a mixing trend
between Ca-Mg waters with strongly Na+K
waters.  The ratio  of Mg/Ca ranges from 0.1 to
5.6, with mean value of 0.6. The anion trilinear
diagram illustrates that most waters are domi-
nated by bicarbonate and chloride with lesser
amounts of sulfate.  Figure 43 shows that most
data follow a  linear correlation of increasing
TDS with increasing bicarbonate; however, a
highest TDS waters are rich in chloride similar
to that observed in the Upper Claiborne aquifer.
The association of chloride with more concen-
trated waters illustrated in  Figure 43, confirms
the presence of a saline, alkaline component
identified in the correlation analysis.

The contour map  distribution of hydrochemical
water types (Figure 44) shows that bicarbon-
ate waters in the Middle Claiborne aquifer
dominate throughout the study area.  The
distribution of HCO3-CI and HCO3-SO4 waters
is erratic and does not follow tectonic features
(Figure 44), recharge, or discharge (cones of
depression) patterns (Figure 45) (Schrader,
2008a). The contour map distribution of TDS
values (Figure 46) shows that the highest con-
centrations are toward the center and southern
part of the ME, with more dilute waters entering
from recharge areas in south-central Arkansas,
central Mississippi, northernmost Mississippi,
and western Tennessee. The contour maps
for sodium, chloride, and bicarbonate show
distributions similar to that of the TDS map.
The contour map distribution of calcium values
(Figure 47) shows the highest values in the
northern central  ME and around the margins.
Although this might  result from relationship to
bicarbonate and  the precipitation of calcium
carbonate,  a similar map pattern is observed
for iron, potassium, and magnesium as well.
This pattern suggests distinct spatial distribu-
tions of sodium-rich versus calcium-, magne-
sium-, iron- and  potassium-bearing waters.

Cluster and principal component analysis
were used to  independently verify water
quality relationships identified through spa-
tial and correlation analysis, and further
explore geochemical processes. Hierarchical
                                    Scatter Plot
ZUIAT


oUO~
n



fi
i:f



>
:



^
eO







C



Legend
C Default
Scale of radii:
Proportional to Cl
0
- 1000rrg/l

                            0    1000  2000  3000  4000  5000
                                     TDS (mg/l)

Figure 43.   Scatter plot of bicarbonate (HCO3) versus total dissolved solids (TDS) data from the Middle
            Claiborne aquifer. Symbol size is scaled to the concentration of chloride. Eleven chloride-rich
            samples with TDS values greater than WOO mg/L are excluded from the plot.

-------
               36-
               34-
               32-
               30-

                                                        Geochemical water type* in tha Middle Caliborna aquifer

                                                        Explanation:
                                                        1 is HC03,2 Is HC03-CI, 3 Is HCO3-SO4 and 4 Is CI-HCO3
                      Reelfoot Rift

                      Alabama-Oklahoma transform

                      Arkansas and Saline River F Z

                      Pickens-Gilbertown F.Z.
                                -92
-90
-88
-82
Figure 44.    Distribution of major water types in the Middle Claiborne aquifer. Reelfoot Rift from Schweig and
              Van Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991). Arkansas and Saline
              River fault zones from Cox et al. (2006).  Pickens-Gilbertown Fault Zone from Bicker (1969).

-------
                                                      !0 KILOMETERS
Figure 45.    Potentiometric surface of the Middle Claiborne (Memphis-Sparta) aquifer in the Mississippi em-
             bayment (Schrader, 2008a).

-------
               36^
                                                          Total Dissolved Solids (TDS) in tire Middle Claibome aquifer
                                                           Explanation: TDS values arc in mgfl
                                                          0  100  200  300  400  500  600  700  800

                                                                  Reslfoot Rift

                                                         — — —  Alabama-Oklahoma transform

                                                                  Arkansas and Saline River F.Z.

                                                                  Pickens-Gilbertown F 2
30^
                                 -92
                             -90
            -88
            -86
            -84
            -82
Figure 46.    Distribution of TDS values in the Middle Claiborne aquifer.  Reelfoot Rift from Schweig and Van
              Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991).  Arkansas and Saline River
              fault zones from Cox et al. (2006).  Pickens-Gilbertown Fault Zone from Bicker (1969).
                36-
                34
                32-
                30-


                                                         Cmldnm (Ca) dbtrlbidoo In the Mlddk Claiborne aquifer


                                                         Fiplanadon: Ca valuer are In mg/I
                                               —   Reelfoot Rift

                                         — — ^   Alabama-Oklahoma transform

                                         	   Arkansas and Saline River F.Z.

                                         	   Pickens-Gilbertown F.Z.
                     -94
                 -92
-90
-88
-86
                                                                                 i
-84
-82
Figure 47.    Distribution of Ca values in the Middle Claiborne aquifer. Reelfoot Rift from Schweig and Van
              Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991).  Arkansas and Saline River
              fault zones from Cox et al. (2006).  Pickens-Gilbertown Fault Zone from Bicker (1969).

-------
dendrogram (Figure 48) and principal compo-
nent analysis yield two geochemical associa-
tions. Association 1 shows linkage between
NaCI, HCO3, temperature and TDS/Specific
Conductance, suggesting contributions from
an alkaline, saline water source potentially at
depth. This component is very similar to that
identified in the Upper Claiborne aquifer, but
appears to have a more focused distribution
in central and ME. Association 2 includes Ca,
Mg, Fe, and K, which is also spatially distinct
(e.g.,  Figure 47).  Association 2 appears to
have some relationship to recharge sources,
either directly in the outcrop area (e.g., central
Mississippi) or in the subcrop region beneath
the Mississippi River Valley alluvium in the
northern ME. Because the Middle Claiborne
aquifer consists of the entire lower to middle
Claiborne interval (i.e., Memphis Sand) north
the 35° latitude but only the Sparta interval to
the south, it is unclear whether Association 2
represents a  hydrochemical signature from two
distinct stratigraphic intervals.
      n using Average Linkage (Between
  Label  Nun












  •''
Figure 48.   Hierarchical dendrogram of the
            geochemical clusters for the Middle
            Claiborne aquifer.
Water in the Middle Claiborne aquifer in the ME
is generally of high quality, except in regions
where high-TDS, sodium-chloride waters are
observed (see Figure 46). Groundwater in the
Middle Claiborne aquifer is used extensively
for industrial, municipal, and domestic supplies
in western Tennessee (Parks and Carmichael,
1990a), Arkansas (Holland, 2007) and
Mississippi (Wasson, 1986). All sodium hazard
categories are encountered (Figure 49), but the
samples are dominantly in the low to medium
salinity hazard categories. Approximately 2%
of the analyses have values that exceed US
EPA primary drinking water standards for fluo-
ride (F-) or nitrate (NO3~). All studied  regions
have concentrations at or above the US EPA
secondary drinking water standards maximum
level for iron  (Fe = 0.3 mg/L), although the
highest levels of iron are observed in the
northern ME.
                                                                      IBM
                                                                  vHazard [Condi
Figure 49.   Wilcox diagram illustrating degree of
            sodium and salinity hazards in the
            Middle Claiborne aquifer.
Water quality characteristics of the Lower
Claiborne- Wilcox Aquifer
The Lower Claiborne-Wilcox aquifer comprises
sand intervals within the Wilcox Formation
and Carrizo  Sand in southeastern Arkansas,
Nanafalia, Tuscahoma, and Hatchetigbee
formations and  Meridian Sand in Mississippi,
and Fort Pillow  Sand in northeastern Arkansas
and western Tennessee (Hosman and Weiss,
1991). Because this aquifer interval includes
several stratigraphic units that may or may not
be hydrologically connected, inferences based
on hydrochemical data may be limited.  As
indicated by the map distribution of wells, the
aquifer is used extensively in northern and
central Mississippi and northwestern Louisiana
and to a lesser  extent in western Tennessee
and Arkansas (Figure 50).

-------
             36-
             34-
             32-
             30-
                  -94        -92        -90        -88       -86       -84

Figure 50.   Well locations in the Lower Claiborne-Wilcox aquifer within the study area.
                                                                             -82
Time-plots of dissolved constituents in samples
from groups of closely spaced wells screened
in the Middle Claiborne aquifer show no con-
sistent trends. Concentration variations from
sampling event to event typically exceed the
range of values observed in long-term trends.
For example, IDS values vary more between
individual sampling events than the variations
modeled by the linear trend lines (Figure 51).

-------
                                                    Fort Pillow Sand
                                                    monitoring locations
                                                Wilcox Formation
                                                monitoring locations
                1942 194T 1952 1967 1962 1967 1972 (977 1982 1987 1962 1997
                                Dm
 1926 1933 1941 1949 1967  1965 1973 1SB1 19S9

               Dae.
D
950 -
850 -
750 -
650 -
550 -
450 -
19
TDS, mg/l



T — — A.
/ * •
/ N
50 1960 1970 1980 19
Dale
Figure 51.   A) Monitoring well group locations in Lower Claiborne-Wilcox aquifer.  B) TDS data from 1942
            to 2001 for Arkansas (Fort Pillow Sand) monitoring locations. C) TDS data from 1925 to 1996
            for Tennessee (Fort Pillow Sand) monitoring well locations. D) TDS data from 1941 to 1984 for
            Louisiana (green square symbols) Wilcox Formation monitoring wells.
Descriptive statistics for the analyses from the
Lower Claiborne-Wilcox aquifer are given in
Table 10.  The values of the standard deviation
are of similar magnitude or exceed the values
of the mean, indicating most parameters have
non-normal  distributions.  Almost all of the
parameters  are positively skewed, indicating
the presence of a tail of larger (outlier) values.
High variance is commonly associated with
large anomalous values.  Only pH, which is
a log-transformed unit, shows negative skew.
Two-fifths of the measured parameters show
kurtosis values between 0 and 10, indicating
only moderate deviation from normal distribu-
tions; however, Ba, Br, Ca, Cl, CO2, F, I, K, Mg,
Mn,  NO3, SO4 Sr, Temperature, and Zn all show
much higher values of kurtosis associated with
highly peaked distributions.

-------
Table 10.  Descriptive statistical parameters for ground water of the Lower Claiborne-Wilcox aquifer in the
          Mississippi embayment.
Parameter
Al, ug/l
B, ug/l
Ba, ug/l
Br, ug/l
Ca, mg/l
Cl, mg/l
C02, mg/l
El.Cond,
uS/cm
F, mg/l
Fe, ug/l
HCO3, mg/l
I, mg/l
K, mg/l
Mg, mg/l
Mn, ug/l
Na, mg/l
NO3, mg/l
O2, mg/l
pH
Si, mg/l
SO4, mg/l
Sr, mg/l
IDS, mg/l
Temp,
Celsius
Zn, ug/l
N
91
149
149
67
1217
1214
514
1104
1152
597
1196
40
1181
1224
483
1212
581
108
1122
1155
1223
100
1079
865
146
Range
100
4
1
98
100
940
364
4950
7
1000
987
8
36
100
7
999
41
9
6
82
740
8.2
984
66
15000
Minimum
0
0
0
0
0
0
0
10
0
0
3
0
0
0
0
1
0
0
3
0
0
0
16
11
0
Maximum
100
4
1
98
100
940
364
4960
7
1000
990
8
36
100
7
1000
41
9
9
82
740
8.2
1000
77
15000
Mean
18.6
0.47
0.01
3.43
9.2
54.73
14.97
628.84
0.46
174.49
262.09
0.3
2.53
3.27
0.03
125.17
0.8
0.76
7.57
19.11
14.76
0.29
306.74
22.24
142.19
Standard
Deviation
25.37
0.9
0.12
15.67
13.22
111.69
25.63
658.7
0.77
224.63
197.19
1.3
2.48
7.54
0.35
142.61
2.63
1.61
0.88
12.34
52.31
0.87
230.42
4.34
1241.34
Variance
643.62
0.82
0.01
245.46
174.74
12474.54
657.07
433881.05
0.6
50456.63
38883.97
1.7
6.18
56.79
0.12
20337.85
6.9
2.6
0.77
152.33
2736.46
0.76
53095.02
18.8
1540919.3
Skewness
2.02
2.14
8.54
4.96
3.08
3.82
6.6
2.62
3.9
1.87
1.12
5.6
5.87
6.84
16.92
2.24
9.34
2.96
-0.66
1.67
9.02
7.94
1.12
3.46
11.99
Kurtosis
3.38
4.07
71.95
24.95
12.21
18.74
71.75
9.84
19.32
2.92
1.03
33.12
56.95
62.21
324.99
7.05
115.49
9.43
0.71
2.74
98.29
70.1
0.4
31.69
144.46
Anomaly
> 18.6
>0.47
> 0.01
> 100
> 100
> 1000
> 370
> 5000
> 0.46
> 1000
> 1000
> 0.3
> 36
> 100
>0.03
> 1000
> 50
> 0.76
> 7.57
> 100
> 740
> 100
> 1000
> 22.24
> 142.19
Correlation analysis shows that amongst
the specific conductance, TDS, and major
constituents the most prominent correlations
are between pH, TDS, EC, Na, Cl and HCO3.
Calcium and Mg, and Mg and SO4 also show
prominent correlations.  Of the minor and trace
constituents, F, Br, and  B show significant cor-
relations to TDS and/or EC, Na, Cl, and HCO3.
Iodine, Sr, and Br also show strong correla-
tions amongst each other and with K, Ca, and
Mg.  Strontium and Br also correlate well with
CO2.  Other strong correlations include Mn to
I and Al, and Fe to I. The correlation matrix is
seemingly more complex than that of the other
three aquifer units, but the presence of a saline,
alkaline sea-water like source is evident.
The Piper diagram for the Lower Claiborne-
Wilcox aquifer in Figure 52 reveals several
geochemical similarities in water composition
to that of the Middle Claiborne aquifer.  The
upper diamond plot shows that most of the
waters are bicarbonate-rich with either Ca+Mg
or Na + K cation compositions; however, a
large number of water samples fall along the
Na+K line. The trilinear cation plot shows
a mixing trend between Ca-Mg waters with
strongly Na+K waters, with most of the waters
plotting close to the Na+K apex. The ratio of
Mg/Ca ranges from 0.0 to 3.3, with mean value
of 0.54  The anion trilinear diagram illustrate
that most waters are dominated by bicarbonate
and chloride with lesser amounts of sulfate.
Figure 34 shows that most data follow a linear
correlation of increasing TDS with increasing

-------
Figure 52.   Piper diagram for water chemistry data from the Lower Claiborne-Wilcox aquifer. See Figure 12B
            for classification fields.
bicarbonate; however, the highest IDS waters
are rich in chloride similar to that observed
in the other Claiborne aquifers. However,
no water analyses had chloride contents in
excess of 1000 mg/L and numerous waters
with anomalously high HCO3 values are pres-
ent. The association of chloride with more
concentrated waters illustrated in Figure 53
is consistent with the presence of a saline,
alkaline component identified in waters from the
other Claiborne aquifers. The high bicarbonate
waters consistently have little or no SO4 and
are consistent  with waters within the Wilcox in
Louisiana interpreted by Mclntosh et al. (2009)
to be dominated  by microbial methanogenesis.

The contour map distribution of hydrochemical
water types (Figure 54) shows that bicarbonate
waters in the Lower Claiborne-Wilcox aquifer
dominate throughout the study area. The
distribution of HCO3-CI and  HCO3-SO4 waters
is generally in the southwestern and central
ME, but it does not follow tectonic features
(Figure 35), recharge, or discharge (cones of
depression) patterns (Schrader, 2008a). An
anomalous region of HCO3-CI, HCO3-SO4, and
Cl waters is present in western Tennessee,
although these are all dilute waters (Figure 54).
The contour map distribution of TDS values
(Figure 55) shows that the highest concentra-
tions are toward the center and southern part
of the ME and Gulf Coast. The contour maps
for sodium, potassium, chloride, and bicarbon-
ate show distributions similar to that of the TDS
map, suggesting up-dip migration mixing with
Gulf Coast brines  (Manor and Mclntosh, 2007,
Mclntosh et al., 2009). Calcium, magnesium,
and sulfate have limited concentration vari-
ance across much of the ME, but show higher
values in southern Arkansas and northern
Louisiana.  The contour map distribution of
iron values (Figure 56) shows the highest
values in proximity to major pumping centers in
western Tennessee (mainly Memphis), central
Mississippi, and northwestern Louisiana.

Cluster and principal component analysis for
the Lower Claiborne-Wilcox aquifer showed
similar relationships to those observed in the
Middle Claiborne aquifer.  Hierarchical  dendro-
gram and principal component analysis yield
two geochemical associations (Figure 57).
Association 1 shows linkage between NaCI,
HCO3, Mn, temperature and TDS/Specific
Conductance, suggesting contributions from
an alkaline, saline water source potentially at

-------
                                2000
Figure 53.
                          400   800  1200  1600  2000
                              TDS(mgfl)

Scatter plot of bicarbonate (HCO3) versus total dissolved solids (TDS) data from the Lower
Claiborne-Wilcox aquifer. Symbol size is scaled to the concentration of chloride.
              36
              34
              32
              3Ch
                                         Hydrogeochemical water types
                                       in the Lower Claiborae aquifer complex
                                                   Explanation: water types defined
                                                      by predominant anion
                                     HC03 HC03-CI HCO3SO4  Cl

                                     -       Reelfoot Rifl

                                     — — —  Alabama-Oklahoma transform

                                     	  Arkansas and Saline River FZ

                                     	  Pickens-Gilbertown F Z
                  -94
                -92
-90
                                                  \
-68

-86
                                                                      :
-84
-82
Figure 54.    Distribution of major water types in the Lower Claiborne-Wilcox aquifer. Reelfoot Rift from
             Schweig and Van Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991).  Arkansas
             and Saline River fault zones from Cox et al. (2006).  Pickens-Gilbertown Fault Zone from Bicker
             (1969).
depth. The inclusion of manganese (Mn) in this
association is puzzling; however, it also has the
greatest scaled distance from other parameters
in the analysis. This component is very similar
to that identified in the other Claiborne aquifers,
and has a focused distribution in central and
southern ME, much  like the Middle Claiborne
aquifer.  Association 2 includes Ca,  Mg, SO4,
and K, which is also spatially distinct.  Iron has
its own distinct behavior and appears  to be
directly related to  pumping centers as illustrated
in Figure 56.
                                       Water in the Lower Claiborne-Wilcox aquifer
                                       in the ME is generally of high quality, except in
                                       regions where high-TDS, sodium-chloride-bicar-
                                       bonate waters are observed (see Figure 55).
                                       Ground water in the Lower Claiborne-Wilcox
                                       aquifer is used for industrial, municipal,  and
                                       domestic supplies in western Tennessee (Parks
                                       and Carmichael,  1989), northeastern and
                                       southwestern Arkansas (Holland, 2007) and
                                       Mississippi  (Wasson, 1986). All sodium hazard
                                       categories are encountered (Figure 58), but
                                       the samples are dominantly in the medium to
                                       high salinity hazard categories. Approximately

-------
               36-
               34-
               32-
               30

                      Total Dissolved Solids (IDS) distribution
                      in Die Lower Claibome aquifer complex


                      Explanation: TDS values are in mg/l

                         °   i  i

                     —•^—  Reelfoot Rift
                      — — —  Alabama-Oklahoma transform
                      	  Arkansas and Saline River F.Z.
                      	  Pickens-Gilbertown FZ
                    -94
-92
-90
-88
-86
-84
-82
Figure 55.    Distribution of TDS values in the Lower Claiborne-Wilcox aquifer. Reelfoot Rift from Schweig and
             Van Arsdale (1996). Alabama-Oklahoma transform from Thomas (1991). Arkansas and Saline
             River fault zones from Cox et at. (2006).  Pickens-Gilbertown Fault Zone from Bicker (1969).
              36-
              34-
              32-
              30-
                                                   Memphis
                               Iron (Fe) distribution
                         in the Lower Claibome aquifer complex
                                                       Explanation: Fe values are in ug/1
                   -94
-92
-90
-88
-86
-84
-82
Figure 56.   Distribution of iron values in the Lower Claiborne-Wilcox aquifer.
2% of the analyses have values that exceed
US EPA primary drinking water standards for
fluoride (F~) or nitrate (NO3~). Most studied
regions have concentrations at or below the
US EPA secondary drinking water standards
maximum level for  iron  (Fe = 0.3 mg/L), except
near major pumping centers such as Memphis
(Figure 56).
                        Discussion of Water Quality in the Tertiary and
                        Quaternary Aquifers
                        The results of the present study illustrate
                        the overall water quality and statistical fac-
                        tors controlling water quality in the four main
                        aquifer units defined in the Mississippi embay-
                        ment. Water from  all four aquifers is suitable
                        for consumption; however, the water in the

-------
                               'HIERARCHICAL CLUSTER  ANALYSIS
                          TDS

                          El.Cond
                          PH

                          Temp
Figure 57.   Hierarchical dendrogram of the geochemical clusters for the Lower Claiborne-Wilcox aquifer.
                                            Wilcox Diagram
                                          Salinity Hazard (Cond)

Figure 58.   Wilcox diagram illustrating degree of sodium and salinity hazards in the Lower Claiborne-Wilcox
            aquifer.
Quaternary Alluvial aquifer is generally of lower
quality (higher TDS, Ca, Mg, and Fe).  Water
from the Quaternary Alluvial aquifer appears
to have hydrochemically distinct origins from
the Tertiary aquifers and shows less variation
in relation to proximity of the Gulf Coast. The
assemblage of factors affecting hydrochemistry
in the Quaternary Alluvial aquifer is reaction
with Fe-Mn oxides and hydroxides, reac-
tion with carbonate minerals (probably from
partially-weathered detritus of glacial origin),
and a mixed salt (Na, K, Cl, and SO4) asso-
ciation that may have geographically distinct
and diverse origins (See Kresse and Clark,
2008). Correlations among trace elements,
such as Cr, Cu, Co, and Pb, in the Quaternary
Alluvial aquifer waters also support origins from
partially weathered detritus, and are distinct
from trace element associations observed in
the deeper aquifers. The overall hydrochem-
istry is also affected by  proximity to the major
river systems, where higher TDS, Ca-Mg-HCO3

-------
waters recharge the aquifer. Prominent regions
of higher Na and Cl are observed in southeast-
ern Arkansas and northern Louisiana which
may have migrated along faults from underlying
aquifers (Bryant et al., 1985; Kresse and Clark,
2008).

In contrast to the Quaternary alluvial aquifer,
the underlying Tertiary aquifers have several
similarities in water quality and  hydrochemistry
that are linked to recharge processes, dis-
charge regions, and proximity to the Gulf Coast.
Overall water quality in each of the Tertiary
aquifers is high and generally increases with
depth (in the central and northern Mississippi
embayrnent). Water type generally varies from
mixed cation-bicarbonate compositions in the
recharge areas to more sodium-rich bicarbon-
ate, bicarbonate-sulfate, or bicarbonate-chloride
waters down stratigraphic dip toward the Gulf
Coast, similar to interpretations in past stud-
ies  (Pettjjohn, 1996). Correlation and factor
analysis consistently shows major and trace
element evidence for mixtures  of sea-water
derived saline; alkaline-waters  are common in
all three Tertiary aquifers.  Vertical increase in
salinity is only apparent in the southern ME
where saline, alkaline fluids have migrated
either up-dip or vertically through the Cenozoic
section (Manor and Mclntosh, 2007; Mclntosh
et al., 2009).  All three Tertiary aquifers include
a carbonate mineral source, similar to that
of the Quaternary Alluvial aquifer, which is
focused in recharge areas, especially beneath
the Mississippi Alluvial valley. In general, major
and trace  element hydrochemistry appears
to be distinct and more dilute in the recharge
areas for the  respective Tertiary aquifers.

Some water quality variations in the southern
ME appear to relate to  migration along fault
structures. Kresse and Clark (2008) argue for
fault-derived salinity in the Mississippi  Alluvial
aquifer in  southeastern Arkansas near the
traces of the Saline and Arkansas River fault
zones (Figures 24 and  25)  (Cox et al., 2006).
Similar association of a saline-alkaline fluid
component with regional structures is appar-
ent in the  Upper Claiborne aquifer (Figures 33
and 34).  Clear evidence of such association,
however, appears lacking in the deeper Middle
Claiborne and Lower Claiborne-Wilcox aquifers.
It is unclear whether this is because these units
represent aggregates of several thin or discon-
tinuous aquifers or if other processes are more
determinant in the water-quality characteristics.

Water-quality changes over time and due to
pumping are limited on a regional basis. The
main effects appear to be subtle increases in
total dissolved solids (e.g., Quaternary Alluvial
aquifer) and changes in oxidation-reduction
conditions (Lower Claiborne-Wilcox aquifer).
However,  the water quality characteristics need
to be evaluated in light of regional water-
table and  potentiometric surfaces.  A regional
potentiometric surface is only available for the
Sparta-Memphis aquifer at present. Although
numerous studies have documented local
changes in water quality related to pumping
and waste-disposal practices (Parks et al.,
1981; Graham and Parks,  1986; Parks, 1990;
Bradley, 1991; Parks and Mirecki, 1992;  Parks
et al. 1995; Kleiss et al., 2000; Larsen et al.,
2003; Gentry et al., 2005; Ivey et al.,  2008), in
the regional view these effects appear at pres-
ent to be localized.

Relationships amongst water sources and
processes affecting water quality are most clear
in the Quaternary Alluvial and Upper Claiborne
aquifers, and less so in the Middle and Lower
Claiborne-Wilcox aquifers. This seems likely
due to the lumped classification of these aquifer
units.  More detailed analysis of the water
quality trends and factors in the lower Tertiary
aquifers will require further subdivision of the
aquifers and regional consistency in application
(see Hydrostratigraphy section).

-------
           of                      in
        and                    in the

Environmental tracers include a variety of
chemical and isotopic measurements that
provide information on ground water recharge
sources, recharge rates, and flow paths
(see Cook and Herczeg, 2000 for a review).
Recharge areas include locations where water
infiltrates from the surface into an aguifer or
from a subsurface source (e.g., gap in con-
finement, fault, etc.) into an aquifer. Surficial
recharge areas are inherently vulnerable to
pollutants that may infiltrate with the water.
Recharge rate is the rate at which the aquifer
is replenished from water infiltrating down from
the ground surface, which varies  with a host
of variables, including time,  location, land use,
and aquifer stress.  The recharge area for an
unconfined alluvial aquifer is practically every-
where on the surface where water can vertically
infiltrate. Recharge areas for confined aquifers
are limited to areas where the aquifers crop
out or subcrop beneath permeable materials.
Recharge areas also identify the  locations that
are vulnerable to contamination.  The shallow
aquifer is most susceptible to contamination,
such as leaching of fertilizers and pesticides
from agricultural fields or trace elements and
organic solvents from landfills. For example, in
1997, ~5.8x104 kg of herbicides, -1.18x104 kg
of insecticides, and 3.4x103 kg of fungicides
were used mostly for cotton and soybean
crops in Shelby County, Tennessee (Gonthier,
2002). Many pesticides have been detected
in both surface water and shallow ground
water in Shelby County (Parks et al., 1981;
Gonthier, 2002) and other shallow wells in the
region (Fielder et al., 1994;  Kleiss et al., 2000).
Confined aquifers are especially vulnerable
to contamination in recharge areas as well as
locations where vertical leakage between aqui-
fers, such as windows in the upper Claiborne
confining unit in Shelby County (Parks, 1990;
Parks and Mirecki, 1992; Gentry et al., 2006).
Thus, the locations as well as rates of recharge
to aquifers are critical for assessing vulnerabil-
ity to contamination.

Environmental tracers are a key tool for
assessing locations  of recharge and recharge
rates. Inorganic chemicals, especially those
associated with specific sources, are useful
as tracers of ground water recharge pathways
and also have potential for evaluating recharge
rate (Herczeg and Edmunds, 2000). Contour
map distributions of water quality character-
istics for each of the Cenozoic aquifer units
provide  information on likely recharge areas
(e.g., locations of dilute water compositions,
reduction-oxidation gradients, etc.). Ground
water hydrochemistry has been  used  in several
studies within the ME region to identify ground
recharge sources and pathways (Mirecki and
Parks, 1994; Parks et al., 1995;  Larsen et al.,
2003; Ivey et al., 2008).

Ground  water age, the time since recharge,
is important in determining ground water flow
velocity  and recharge rate (Cook and  Solomon,
1997).  Ground water age can be determined
by using a variety of isotopic tracers, such as
tritium-helium (3H/3He), carbon-14 (14C), chlo-
ride-36 (36CI), and helium-4 (4He), each with
its own dating limitations. Tritium (3H) provides
information on the presence of modern water
(<60 years old), but cannot be used under
most circumstances to estimate  recharge
rates. Tritium data exist for many shallow
wells throughout the ME region  (Brahana et
al., 1985; Graham and Parks, 1986; Slack and
Oakley,  1989; Bradley, 1991; Parks et al., 1995;
Larsen et al.,  2005), but the data are gener-
ally from study areas of restricted extent or
are widely dispersed wells in various geologic
units. The 3H/3He technique is used to date
young ground water (less than 60 years) (Cook
and Solomon 1997; Solomon et  al 1993). The
3H/3He technique has been used successfully
in many studies in the Memphis area  (Larsen
et al., 2003; Larsen et al., 2005;  Gentry et
al., 2005; 2006; Ivey et al., 2008) and holds
much potential for more regional assessment
of recharge locations and rates.  Radioactive
14C is useful for dating ground water that has
little dissolved carbonate and is  between 1,000
and 30,000 years old (Coplen, 1993; Fontes,
1979).  Several surveys of radioactive 14C have
been done in the ME region (Brahana et al.,
1985; Graham and Parks, 1986), but most
have focused on study areas of  limited extent
or  widely dispersed wells.  CI-36 is a good

-------
indicator of both young waters (bomb-pulse
age, Phillips et al., 1988) and waters hundreds
of thousands of years old (Phillips et al,, 1986;
Fehn et al., 1992). Little work with 36Cl has
been done in the region (Davis et al., 2003),
but it has potential for constraining the age of
old and deep ground water. Radiogenic 4He can
be used to corroborate 14C (Carey et al., 2004;
Bowling et al.,  2004; Hendry et al., 2005, Hunt,
2000).  Noble and  nitrogen  (determined during
d15N analysis) gas data are used to evaluate
recharge temperatures and potential for mixing
of gas  sources (Aeschbach-Hertig et al., 1999),
both of which are  important for applying gas-
based  age models.

Chemical signatures and environmental tracers
are invaluable for  numerical ground-water  flow
model  calibration and analytical ground-water
flow modeling. Measuring geochemical and
isotopic characteristics (including apparent
ground-water ages) help determine both the
source and age of water currently in the aquifer
and constrain computer simulations, which
will be  used to evaluate ground-water appar-
ent age and source distribution. An important
component of ground-water flow models is to
determine the area and rate of natural replen-
ishment for confined aquifers.  Environmental
tracers and modeling provide a unique and
well-constrained hydrologic characterization of
a multiple layered aquifer system, which should
serve as a model  for developing exploitation
strategies in other similar aquifer systems.

Conduct             on
                   and
methodologies
Water production in the region based on
historic records has been ongoing since the
rnid-1800's.  Well production capacity and, at
the time under artesian conditions, outflow pro-
vided insight into the capability of the aquifers
to produce sustainable quantities of flow. To
quantify this capability, hydraulic conductiv-
ity and storage are needed. Additionally, to
address contamination potential and fate,
porosity of the aquifer material and hydro-
geologic characterization of the aquitards will
be required. Two information sources were
analyzed for measured values of hydraulic
conductivity, storage and porosity: (1) published
literature and (2) the USGS database.


A number of publications were reviewed,
but after removing coincident references
and following references back to the original
source,  only thirteen sources could be identi-
fied (Table 11).  The table shows the hydraulic
conductivity, transmissivity, storativity, and
permeability values for the three major aquifers
in the Memphis area. The values shown were
cited from reports that were focused on the
aquifers in the Memphis area and the sur-
rounding counties.  The majority of studies in
the Memphis area cite values  given by (Arthur
and Taylor, 1990) and (Moore  1965). Two
heavily cited papers are a good example of
this (Brahana.and Broshears 2001; Parks and
Carmichael, 1990a).  Slack and Darden (1991)
summarized all of the aquifer tests done in
Mississippi from June 1942 to May 1988, but
none of these test locations were in northern
Mississippi counties.  Newcome (1971) also
reports aquifer test values for  Mississippi, but
these are not located in northern  Mississippi
either.  Krinitzsky and Wire (1964) report
transmissivity values ranging from 12,000 to
54,000 ft2/day, but this report is out of circula-
tion and the location of these tests could not
be confirmed.  The values given by Layne
Geosciences and EnSafe are  unpublished
results.  Unfortunately for many of the records,
location detail below the state or county scale
did not exist thus preventing the mapping of the
values.  The aquifer formation and aquifer name
were extracted from the author's description of
the units.  As will be discussed in the USGS
aquifer parameter assessment section, factors
such as what aquifer testing method was used,
multiple wells pumping during the test, short
testing periods, and lack of supporting informa-
tion may reduce confidence in a recorded value
thus warranting caution in its use and the need
for more aquifer tests. Without well number
identification accompanying the records listed
in Table 11, correlation of these values to those
assessed in the next section cannot be made,
and thus no determination of reliability applied.

-------
 USGS historic records
 The USGS has the largest public database of
 aquifer test data in the region.  This database
 includes values for hydraulic conductivity,
 transmissivity, specific capacity, and storage.
 The question raised is whether the measured
 aquifer parameter values are reliable.  Reliable
 in this sense is a qualitative  measure that
 is a function of method(s) used, supporting
 documentation, and the presence of extrane-
 ous factors that might impact an aquifer test
 like having multiple wells pumping (e.g., well

Table 11.  Aquifer parameter data from literature review.
field) or wells turning on and off during testing.
For this study, as much information about an
aquifer test was compiled and a scoring matrix
developed for the assessment tool.

The USGS aquifer parameter data is catego-
rized by aquifer; the naming convention is that
used in the USGS database yet correlated
as best as possible to that described under
the geology section. The  aquifer names are:
(1)  Qal (Quaternary alluvium); (2) Tcf (Tertiary
confining unit or Upper  Claiborne); (3) Tm
(Memphis/Sparta or Lower Claiborne);  and
Author(s)
(Arthur, J. and Taylor,
R.1990)













(Criner, J. et al. 1964)


(Gentry, et al. 2006)

(Hosman et al. 1968)










K.
(ft/day)
81
47
69
69
65
63
42
86
65
172
-
49
-

-
-

80-100

23
9
-
-
-
-
11
-
-
22
35
T
(ft2/day)
3333
25649
15616
5358
5960
4754
2536
9343
6283
7668
486
14963
17780

53472
16043

-

21390
10026
13102
7353
2674
26738
20053
33422
29412
18717
25401
S
-
-
-

-
-
-
-
-





0.003
0.00028



0.0002
0.0015
0.0002
0.0009

0.0001
0.011
0.001
-
0.0005
0.0007
AREA
TN
TN
TN
MS
MS
MS
MS
MS
AR
AR
AR
AR
AR

Memphis
Memphis

Memphis, TN

MS Co AR
Madison Co, TN
Shelby Co, TN
St. Francis Co, AR
Fayette Co, TN
Haywood Co, TN
Madison Co, TN
Shelby Co, TN
Tipton Co, TN
Crittendon Co, AR
MS Co, AR
AQUIFER
FORMATION
Upper Claiborne
Middle Claiborne
Lower Wilcox
Upper Claiborne
Middle Claiborne
Lower Claiborne-
Upper Wilcox
Middle Wilcox
Lower Wilcox
Upper Claiborne
Middle Claiborne
Lower Claiborne-
Upper Wilcox
Middle Wilcox
Lower Wilcox

Claiborne Formation
Lower Wilcox

Middle Claiborne

Lower Wilcox
Lower Wilcox
Lower Wilcox
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Quaternary Aquifer
Quaternary Aquifer
AQUIFER NAME
Cockfield Formation
Upper Memphis
Sand
Fort Pillow
Cockfield Formation
Sparta Sand
Winona Sand
Middle Sand in
Wilcox Group
Lower Sand in
Wilcox Group
Cockfield Formation
Sparta Sand
Carrizo Sand
Middle Sand in
Wilcox Group
Lower Sand in
Wilcox Group

Memphis Sand
Fort Pillow

Memphis Sand

Fort Pillow
Fort Pillow
Fort Pillow
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Shallow or Alluvial
Shallow or Alluvial

-------
Table 11 (cont.). Aquifer parameter data from literature review. Readers are referred to Pugh (2008) for addi-
tional values published after the completion of this investigation.
Author(s)


(Mahon and Poynter
1993)

(Moore 1 965)


















(Moral, personal com-
munication 2008)
n = 0.34


(Parks and Carmichael,
1988)

(Plebuchetal. 1961)

(Robinson et al. 1997)

(Schneider and Gushing
1948)





(unpublished EnSafe
1992)

(unpublished Layne
Geosciences 2001)
(ft/day)
45

120-390

-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-

100
40
0.02

-

-

5-150

-
-
-
-
-

60

48
T
(ft2/day)
40107

-

18717
22326
29411
27139
21390
40508
2674
42781
26203
45454
35428
31150
26738
23396
23396
21000
10000
43000

-
-
-

1500-
2500

138000

-

16979
13636
13369
18449
15107

36216

27380
S
0.02



0.0004
-

0.0001

0.0014

0.0002
-
-
-
-
-
-
-
0.002
-


-

-

0.0003

0.00046

-

0.00042
0.00017
0.00023
0.00038
0.00021

-

0.0002
AREA
St. Francis Co, AR

Eastern Arkansas

Dyerburg, TN
Ripley, TN
Covington, TN
Stanton, TN
Arlington, TN
Millington, TN
Somerville, TN
Mem(McCord)
Mem(Mallory)
Memphis, TN
Mem (Sheahan)
Mem (Allen)
Mem (Lichterman)
Germantown, TN
Collierville, TN
Blytheville, AR
Madison Co, TN
St. Francis Co, AR

Memphis, TN
Memphis, TN
Memphis, TN

Lauderdale Co,
TN

Crittendon Co, AR

Millington, TN

Allen Field
Sheahan Field
Buckeye Oil Plant
Sheahan Field
Sheahan Field

Collierville, TN

Collierville, TN
AQUIFER
FORMATION
Quaternary Aquifer

Quaternary

Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Middle Claiborne
Lower Wilcox
Lower Wilcox
Lower Wilcox

Quaternary
Middle Claiborne
Upper Claiborne

Upper Claiborne

Quaternary

Alluvial-Fluvial
Deposits

Lower Wilcox, 1400 ft
sands
Lower Wilcox, 1400 ft
sands
Lower Wilcox, 1400 ft
sands
Lower Wilcox, 1 400 ft
sands
Lower Wilcox, 1 400 ft
sands

Middle Claiborne

Middle Claiborne
AQUIFER NAME
Shallow or Alluvial

Mississippi River
Alluvial

Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Memphis Sand
Fort Pillow
Fort Pillow
Fort Pillow

Shallow or Alluvial
Memphis Sand
Confining Unit

Cockfield Formation

Shallow or Alluvial

Shallow or Alluvial

Fort Pillow
Fort Pillow
Fort Pillow
Fort Pillow
Fort Pillow

Memphis Sand

Memphis Sand

-------
(4) Tfp (Fort Pillow or Wilcox).  No aquifer
parameter data exists for the remaining geo-
logic units investigated under Topic 2. As
shown in Table 12, the vast majority (93.4%) of
aquifer test data resides in Shelby County with
the larger portion of tests performed within the
Memphis/Sparta aquifer.  Very few aquifer tests
have been recorded outside Shelby County
with no tests on record in Hardeman, Marshall
and Tunica counties.

Table 12.   Breakdown of USGS aquifer parameter
           tests by county and aquifer.
State
Tennessee
Tennessee
Tennessee
Tennessee
Arkansas
Mississippi
Mississippi
Mississippi
County
Shelby
Fayette
Tipton
Hardeman
Crittenden
Desoto
Marshall
Tunica
Geoloc
Qal
1
-
-
-
2

-
-
Tcf

1
-
-


-
-
ic Unit
Tm
85
1
1
-

1
-
-
Tfp
28
-
-
-
2
-
-
-
Percentage
of total
records
93.4
1.6
0.8
-
3.3
0.8
-
-
A scoring matrix of nine criteria was used
to qualitatively assess the reliability of the
aquifer parameter data recorded by the USGS
(Table 13). Meeting the criteria would either
reduce or increase a record's score from its
base value of 10.  Ten was selected as the
initial score so resulting scores would be
non-negative (minimum = 0).  Determining a
threshold score  to differentiate between reliable
and  non-reliable records is difficult.  It is recom-
mended  that scorings for records be  reviewed
on an individual basis, guided by the user's
intended purpose for using the values.

A general discussion of the scoring is dis-
cussed herein following Table 14. With a
starting score of 10, the average score for
each aquifer was below 5. Only one aquifer
parameter test was conducted within the
Upper Claiborne confining clay (Tcf), that
listing located in eastern Fayette County where
according to this investigation this unit is
absent.  This raises the question of positional
accuracy of the  data which was not assessed
under this investigation. The majority of the
records are for the Memphis aquifer in Shelby
County.  A moderate percentage of the wells
(28%) used in aquifer testing are affiliated with
well clusters (or well fields), thus accounting for
an added increase in the score due to avail-
able nearby observation wells. The score is
increased further because 47% of the analyses
equal or exceed a 24 hour testing period. Yet
the influence of multiple pumping  wells (i.e.,
drawback of being in a  well cluster), lack of
supporting information, no use of multiple
analytical methods, and limited  drawdown/
recovery analyses counter any gain in scores
for this aquifer, and similarly for the other units,
therefore, resulting in the low average scores.

Table 13.   Scoring matrix used to qualitatively as-
           sess the reliability of the USGS aquifer
           parameter data.
                                                                     Rank Criteria
                                                    Published or Approved (yes + 1)
                                                    Have the test results been published in a USGS report?
                                                    If yes, plus 1
                                                    Multiple pumping wells (yes -2)
                                                    Are nearby pumping wells affecting the test?
                                                    If yes, minus 2
                                                    Other well on and off (yes -5)
                                                    Are nearby pumping wells turning on and off?
                                                    If yes, minus 5
 Observation wells (unknown -1, no -2)
 Were water levels monitored in observation wells for the
 aquifer test?
 If unknown, minus 1
 If no, minus 2
 Test duration (>24 hours +1, unknown -1, <24 hours
 -2, <1 hour -3 )
 If the pumping duration is more than 23 hours, plus 1
 If the pumping duration is unknown, minus 1
 If the pumping duration is less than 24 hours, minus 2
 If the pumping duration is less than 1  hour, minus 3
 Good supporting information (no -2)
 Do the records provide good supporting information for
 the test?
 If not, minus 2
 Multiple Analyses (test +1; wells -1; no -2)
 Were multiple analytical methods used in the analysis?
 If yes, plus 1
 If no, minus 2
 Multiple Wells Analyzed (yes +1)
 Were analysis conducted on multiple wells for the test?
 If yes, plus 1
 Drawdown and recovery analyses (no -2)
 Were the drawdown and recovery data both analyzed?
 If not, minus 2
A distribution of the scores aggregated for all of
the aquifers is shown in Figure 59. Choosing
an arbitrary threshold of seven, only 19% of
the records can be considered reliable.  This
number drops significantly to 7% for scores
of eight or greater.  Figure 60 shows the

-------
distribution of reliable aquifer parameter records
with a score of seven or higher.  As indicated,
reliable aquifer parameter data becomes limited
to Shelby County.

Not only  is horizontal spatial distribution
important, but vertical discretization within the
Memphis/Sparta aquifer is equally important for
reasons of apparent aquifer compartmentaliza-
tion as mentioned  in Topic 2. Using a threshold
score of seven, the records with scores 9 to
11 are clustered in the northern  part of Shelby
County with the wells screened in the upper
section of the Memphis aquifer (Figure 60).
Three records (score = 8) are clustered in
south middle Shelby County, also represent-
ing  the upper section of the Memphis aquifer.
Nine of the records (score = 7) are screened
in the middle to upper section of the Memphis
aquifer. The  remaining five records (score = 7)
are screened within the Fort Pillow aquifer, yet
three of the records represent an aquifer test
performed on the same well.

Table 14.   Number of USGS aquifer parameter re-
          cords that match the assessment criteria
          and the  average score by aquifer.
1
3
o-
<
Total Number
Published or
Approved (yes)
Multiple pumping
wells (yes)
Other well on
and off (yes)
Observation
wells (no)
Test duration
(>/=24 hours)
Test duration
unknown
Test duration
(<24 hours)
Test duration
(<1 hour)
 Qal   3    1    0    0   2     0210

 Tcf   1    1    0    1   0     1001

 Tm  88  20   14    0   19    41     3   44    1

 Tfp  32   0    4    0   2    12     1   19    0
1
^
cr
<
Total Number
Good supporting
information (no)
Multiple Analytical
Methods (yes)
Multiple Analytical
Methods (no)
co "en"
— CD
i -5>
a"§
Q. N
= >>
13 CO
^§
Drawdown and
recovery
analyses (no)
CD
8

CD
CT>
CO
1
Minimum Score
Maximum Score
 Qal   3    2    0    3    0     2     31

 Tcf   1    0    0    1    0     1     4    -

 Tm  88  56   3   88   25    68   4.1   0

 Tfp  32  13   0   32   1    30   4.4   0
7

11
This limited number of aquifer parameter data
and weak spatial distribution (i.e., horizon-
tally, vertically within the larger aquifer (e.g.,
         Memphis/Sparta), and vertically inclusive of all
         the geologic units under investigation) across
         the study area strongly suggests a major
         deficiency in the characterization of the aquifers
         and their confining units, thus, warranting that
         any future ground-water modeling efforts should
         include a plan to rectify this data gap.
I
                                  i
                 0123456789   ID  11

                                 Score
         Figure 59.    Distribution of USGS aquifer parameter
                     assessment scores for all geologic
                     units.
                                         WQ'ffVY


                                      Legend

                                       • Fort PŦow (SOX* = 7)

                                      Mo mp his/Sparta
         Figure 60.    L/SGS aquifer parameter records with a
                     score of 7 or greater.

-------
Catalog surface water sources to ground
water
Of the surface water bodies encountered in
the study area, rivers are the only system that
has historic data associated with them.  Lakes
and wetlands are recognized as having an
impact on the ground water, but have not been
investigated beyond identifying their location,
size, and in regard to wetlands, their classifica-
tion. This task is subdivided into five subtasks:
(1) gaging station information; (2) assessment
of baseflow conditions; (3) availability of digital
wetland data; (4) determination of riverbed
conductance; and (5) compilation of soils data.

Gaging stations
There are 22 gaging station locations within the
study area footprint (Figure 61). Two of these
stations are on the Mississippi River, operated
by the Memphis district US Army Corps of
Engineers (USAGE). Stage and discharge are
measured at both locations and the records
can be found at http://www.mvm.usace.army.
mil/.  There are five main branch channels to
the Mississippi River within the study region:
(1) Hatchie River (TN); (2) Loosahatchie River
(TN); (3) Wolf River (TN); (4) Nonconnah Creek
(TN); and (5) Coldwater River (MS). On these
branches and their tributaries, there are 20
gage locations, but only 11 are currently active
(Figure  61).  These 11 gages are maintained
by the USGS with the records for each gage
available at http://water.usgs.gov/waterwatch/
or at the links provided in Appendix Gages (the
Station  ID in Figure 61 is associated to the ID's
in the appendix). Also provided in Appendix
Gages is the type of data recorded (e.g., real-
time, discharge, stage, field measurements,
etc.)  and date range of activation.  Table 15
summarizes the location and activation date
range for the gages shown in Figure 61. Data
from the monitored tributary gages are used in
the next section to assess baseflow conditions.
                    12.5
                         25
                                    50 Miles
           Legend

             •  Mississippi River gages
             A  Monitored tributary gages
             •  Abandoned tributary gages
              — Major rivers
           |    | County
Figure 61.    Monitored and abandoned gaging station locations.

-------
Table 15.  Location and date of activation information for gage stations shown in Figure 61.
Latitude
35.310863
35.187777
35.16928
35.116388
35.049722
35.109444
35.054166
35.0325
35.275247
35.637255
34.9075
35.055672
35.13278
35.201594
35.281111
35.237486
35.189166
35.187777
35.168583
35.128888
35.048485
34.52862
Longitude
-89.63948
-89.975555
-89.866038
-89.801388
-89.818888
-89.657777
-89.541111
-89.246666
-88.976569
-89.609377
-89.753333
-88.799277
-89.854913
-89.922813
-89.765555
-89.951427
-89.761666
-89.835833
-89.824297
-89.710277
-90.193094
-90.574797
Date range of
activation
Oct 1969 to Sep 2008
Feb 1985 to Sep 2008
Apr 1996 to Oct 2008
Oct 1969 to Sep 2008
Oct 1969 to Sep 2008
Nov 2007 to Dec 2008
Aug 1929 to Sep 2008
Sep 1995 to Sep 2008
Aug 1929 to Sept 2008
Jan 1939 to Sep 2008
Oct 1954 to Dec 2008
Nov 1940 to Dec 1969
Oct 1986 to Dec 1990
Jun 1936 to Dec 1969
Feb 1939 to Dec 1969
Nov 1976 to Sep 1983
Jun 1974 to Nov 1983
Nov 1977 to Feb 1982
Dec 1974 to Sep 1977
Oct 1954 to Jun 1957


Drainage
area (mi2)
262
788
30.5
699
68.2
3.61
503
210
1480
2308
191
837
709
771
505
1.26
1.45
21.4
3.18
13.6


Station
ID
1
2
3
4
5
6
7
8
9
10
11
12
14
15
16
17
18
19
20
21
22
23
River
Loosahatchie River
Wolf River
Fletcher Creek (trib to Wolf River)
Wolf River
Nonconnah Creek
Mary's Creek (trib to Gray's Creek: Wolf River)
Wolf River
Wolf River
Hatchie River
Hatchie River
Coldwater River
Hatchie River
Wolf River
Wolf River
Loosahatchie River
Loosahatchie River
Fletcher Creek (trib to Wolf River)
Fletcher Creek (trib to Wolf River)
Fletcher Creek (trib to Wolf River)
Gray's Creek (trib to Wolf River)
Mississippi River: Memphis , TN
Mississippi River: Helena, AR
Baseflow conditions
Ground-water recharge can be partitioned into
shallow or deep recharge. Shallow recharge
as compared to deep recharge has a short
residence time in the subsurface and is the
contributor to stream baseflow.  Deep recharge
is a very small fraction (<5-10%) of the total
recharge and  becomes an important factor in
managing ground-water resources in confined
aquifer systems. Unfortunately, deep recharge
is difficult to quantify (Strieker, 1983). One
method of estimating deep recharge is to
quantify the other hydrologic cycle components
(precipitation, evapotranspiration, runoff (which
includes stream baseflow)) over an area and
derive deep recharge via a water balance.
However, it is  recognized that measurement
and instrumentation errors are ineluctable and
that the magnitude  of the accruing error may
exceed deep recharge. Though deep recharge
may not be able to  be determined, stream
baseflow (or shallow ground-water recharge)
is still an important factor. In a ground-water
system, streams are stressors to the system
whether as sinks for ground water or contribu-
tors to the ground-water regime.  Additionally,
ground-water contribution to streams can have
an impact on water quality and plays a major
role in the biogeochemical cycle of the hyporhic
zone.

Within the MERGWS study area, there is not
enough hydrologic and geochemical informa-
tion to draw correlations between stream
baseflow and deep recharge or water quality/
biogeochemical impacts. Though these analy-
ses cannot be performed, baseflow conditions
of four main MERGWS streams and four tribu-
taries were estimated from  discharge records
from eighteen USGS gaging stations using
three techniques: (1) partial duration curves;
(2) streamflow partitioning using the PART
software package; and (3) hydrograph separa-
tion using the USGS WHAT software package.

-------
Three filter techniques were employed with
WHAT: (1) local minimum, (2) BFLOW; and
(3) Eckhardt. The gaging stations represent a
wide range of drainage areas (1.26 to 788 mi2)
and dates of record (1 to 11 years) (see
Table 16).

Partial Duration Curves
Various authors have reported that partial
duration curves can be used to indicate values
of baseflow or groundwater contribution to
streamflow.  The partial duration flow curve is
a cumulative frequency curve that shows the
percent of time which specified discharges are
equaled or exceeded in a given period. All of
the mean daily flows for a given stream at a
given gage are used for developing a partial
duration flow curve as opposed to the annual
maximum flow where the largest mean daily
flow to occur in a given year is used to predict
frequency events. To assess baseflow condi-
tions, a flow-duration point can be selected
representing the percentage of flow that occurs
equaled to or greater than a chosen flow rate,
the chosen flow rate and percent often labeled
as Q% (e.g.,  Q90, Q65, etc...).  Strieker (1993)
investigated streamflow hydrographs for 35
stations in the southeastern coastal plain
of South Carolina, Georgia, Alabama, and
Mississippi, following the procedure outlined by
Riggs (1963) for developing baseflow recession
curves.  Strieker reported that baseflow values
for streams with a mean baseflow < 10 cfs that
either the 60 or 65 percent duration flow would
Table 16.  Gaged streams investigated for baseflow conditions
Site
Number

Site Name

Latitude

Longitude

HUC8

Drainage
(mi2)

Continuous
period(s) of
record

State of Tennessee
7030240
7030280
7030295
7030392
7031500
7031650
7031680
7031683
7031685
7031692
7031700
7031740
7032200
7032222
7032224

Loosahatchie River at Arlington, TN
Loosahatchie River at Brunswick, TN
Tributary to Loosahatchie River at New
Allen Road
Wolf River at LaGrange, TN
Mary's Creek near Fisherville, TN - tribu-
tary to Wolf River
Wolf River at Germantown, TN
Fletcher Creek at Sycamore View Road -
tributary to Wolf River
Fletcher Creek at Whitten Road - tributary
to Wolf River
Fletcher Creek at Charles Bryan Road -
tributary to Wolf River
Fletcher Creek at Sycamore View Road -
tributary to Wolf River
Wolf River at Raleigh, TN
Wolf River at Hollywood Street
Nonconnah Creek near Germantown, TN
Tributary to Johns Creek at Holmes Road
Johns Creek at Raines Road - tributary to
Nonconnah Creek

35018'39.11"
35°16'52"
35°14'14.95"
35001'57"
35°07'44"
35°06'59"
35°11'21"
35°11'16"
35°10'06.90"
35°10'09.41"
35°12'05.74"
35°iri6"
35°02'59"
35°00'20"
35°02'05"

89°38'22.13"
89°45'56"
89°57'05.14"
89°14'48"
89°42'37"
89°48'05"
89°45'42"
89°50'09"
89°49'27.47"
89051'57.74"
89°55'22.13"
89°58'32"
89°49'08"
89°52'16"
89°53'10"

8010209
8010209
8010209
8010210
8010210
8010210
8010210
8010210
8010210
8010210
8010210
8010210
8010211
8010211
8010211

262
505
1.26
210
13.6
699
1.45
21.4
3.18
30.5
771
788
68.2
5.83
19.4

1970-2006
1940-1949;
1951-1964
1977-1982
1995-2006
1955-1956
1970-1985; 1991-
1995; 1997-2006
1975-1982
1978-1981
1975-1976
1997-2006
1937-1962;
1964-1969
1997-2006
1970-1983; 1986-
1994;1997-2006
1976-1984
1976-1981

State of Mississippi
7275900
7277700
Coldwater River near Olive Branch, MS
Hickahala Creek near Senatobia, MS -
tributary to Coldwater River
34°54'27"
34°37'55"
89°45'12"
89°55'28"
8030204
8030204
191
121
1997-2006
1987-2006

-------
give reasonable estimates of the mean annual
baseflow.  Because of the geologic similarities
between Strieker's sites the MERGWS study
area, the Q60 was used.

The mean daily flows for the river gages listed
in Table 16 were downloaded from the USGS
National Water Information System (NWIS)
database. The data was sorted in descend-
ing order from highest daily value, and the
Q60 determined  using the Weibull  criteria.
The resulting Q60 for each stream is listed in
Table 17.  Calculations of average annual flow
rate per square mile and the intensity are also
presented. Outlaw and Weaver (1996) pre-
pared a report of flow duration and low flows
of Tennessee streams through 1992. Five
stations from this study were reported and
are listed in Table 17 with the values from the
above report shown in parenthesis.  The Q60 in
the report for the 5  stations compared favorably
with those calculated in this report.  The same
analytical procedures were used in the Outlaw
and Weaver  (1996) report as was used in this
report.
Table 17.  Baseflow values estimated using partial duration curves.
Site
Number

Site Name

Drainage
area (mi2)

Period of
record

Qeo Ms)

Intensity
(in/yr)

State of Tennessee
7030240
7030280
7030295
7030392
7031500
7031650
7031680
7031683
7031685
7031692
7031700
7031740
7032200
7032222
7032224

Loosahatchie River at Arlington, TN
Loosahatchie River at Brunswick, TN
Tributary to Loosahatchie River at New Allen Road
Wolf River at LaGrange, TN
Mary's Creek near Fisherville, TN - tributary to Wolf River
Wolf River at Germantown, TN
Fletcher Creek at Sycamore View Road - tributary to Wolf
River
Fletcher Creek at Whitten Road - tributary to Wolf River
Fletcher Creek at Charles Bryan Road - tributary to Wolf
River
Fletcher Creek at Sycamore View Road - tributary to Wolf
River
Wolf River at Raleigh, TN
Wolf River at Hollywood Street
Nonconnah Creek near Germantown, TN
Tributary to Johns Creek at Holmes Road
Johns Creek at Raines Road - tributary to Nonconnah
Creek

262
505
1.26
210
13.6
699
1.45
21.4
3.18
30.5
771
788
68.2
5.83
19.4

1977-1982
1951-1962
1977-1982
1997-2005
1955-1956
1997-2005
1976-1981
1978-1981
1975-1976
1997-2005
1951-1962
1997-2005
1997-2005
1976-1981
1976-1981

109 (105)
118 (117)
0.08
163
1
450 (439)
0.19
1.2
0.27
2.7
340 (337)
530
3.3 (1.9)
0.34
1.3

5.65
3.17
0.86
10.54
1.00
8.74
1.78
0.76
1.15
1.20
5.99
9.13
0.66
0.79
0.91

State of Mississippi
7275900
7277700
Coldwater River near Olive Branch, MS
Hickahala Creek near Senatobia, MS - tributary to
Coldwater River
191
121
1997-2005
1997-2005
81
46
5.76
5.16
Computer Program PART
PART is a computer program that uses stream-
flow partitioning to estimate a daily record
of baseflow below the streamflow record
(Rutledge, 1998).  Rutledge contends that
the  method of baseflow record estimation is a
relatively arbitrary procedure of estimating a
continuous record of groundwater discharge,
or baseflow, under the streamflow hydrograph.
If the stream flow record is incremental (such
as daily) instead of continuous, estimates of
ground water discharge can be made on an
incremental basis.  Rutledge further notes
that the period of analysis is long enough that
the effect on the water balance of changes  in
storage can be considered negligible; hence,

-------
the mean groundwater discharge can be
considered the effective recharge.

In  PART, the program scans the discharge
record for days that fit a requirement of ante-
cedent recession, designates baseflow to
be equal to streamflow on these days, and
performs a linear interpolation to determine the
baseflow for  days that do not fit the requirement
of  antecedent recession. The program is com-
monly applied to a long period of record to give
an estimate of the mean rate of ground-water
discharge. Because of possible inner-basin cli-
matic variation, PART should be executed using
data  over a uniform time period.  A uniform time
period is derived using the program, SCREEN.
Rutledge (1998) provides basin size limits
for using PART.  For estimating recharge or
discharge, only drainage areas larger that one
square mile should be used so as to meet the
requirement of antecedent recession having to
exceed the time increment of the data  (1 day) -
500 square miles may be used as the  drainage
basin upper limit.

PART was used to analyze baseflow condi-
tions in streams using 17 gage sites. Table 18
provides the values of annual mean stream
flow, annual mean baseflow, and baseflow
index for discharge records at these loca-
tions. The baseflow index, BFI,  represents
the mean annual baseflow rate divided by the
mean annual stream flow rate. Two values for
the Germantown gage on the Wolf River are
presented because of two different discharge
periods. Loosahatchie station, 0730240, was
not included due to irreconcilable data  read
errors.
Table 18.   Baseflow values estimated using PART.
Site
Number

Site Name

Drainage
area
(mi2)

Period of
record

Mean Streamflow
Q (cfs)

Intensity
(in/vr)

Mean Baseflow
Q (cfs)

Intensity
(in/vr)

Baseflow
Index
(%)

State of Tennessee
7030280
7030295
7030392
7031500
7031650
7031650
7031680
7031683
7031685
7031692
7031700
7031740
7032200
7032222
7032224

Loosahatchie River at Arlington, TN
Loosahatchie River at Brunswick, TN
Tributary to Loosahatchie River at New
Allen Road
Wolf River at LaGrange, TN
Mary's Creek near Fisherville, TN - tributary
to Wolf River
Wolf River at Germantown, TN
Fletcher Creek at Sycamore View Road -
tributary to Wolf River
Fletcher Creek at Whitten Road - tributary
to Wolf River
Fletcher Creek at Charles Bryan Road -
tributary to Wolf River
Fletcher Creek at Sycamore View Road -
tributary to Wolf River
Wolf River at Raleigh, TN
Wolf River at Hollywood Street
Nonconnah Creek near Germantown, TN
Tributary to Johns Creek at Holmes Road
Johns Creek at Raines Road - tributary to
Nonconnah Creek

505
1.26
210
13.6
699
699
1.45
21.4
3.18
30.5
771
788
68.2
5.83
19.4

1951-1962
1977-1982
1997-2005
1955-1956
1997-2006
1997-2005
1976-1981
1978-1981
1975-1976
1997-2005
1951-1962
1997-2005
1997-2005
1976-1981
1976-1981

666.63
1.69
318.17
13.15
1042.51
1080.15
2.19
37.18
5.24
58.89
972.11
1286.25
116.49
7.91
30.92

17.93
18.23
20.58
13.13
20.26
20.99
20.52
23.6
22.4
26.23
17.13
22.17
23.2
18.43
21.65

141.22
0.18
198.56
1.11
645.07
658.05
0.15
1.68
0.41
4.07
533.09
773.19
9.28
0.79
2.25

3.8
1.98
12.84
1.11
12.54
12.79
1.43
1.07
1.75
1.81
9.39
13.33
1.85
1.84
1.58

21.2
10.8
62.4
8.4
61.9
60.9
7.0
4.5
7.8
6.9
54.8
60.1
8.0
10.0
7.3

State of Mississippi
7275900
7277700
Coldwater River near Olive Branch, MS
Hickahala Creek near Senatobia, MS -
tributary to Coldwater River
191
121
1997-2005
1997-2005
247.33
182.5
17.59
20.49
103.49
61.88
7.36
6.95
41.8
33.9

-------
Program WHAT
Web-Based Hydrograph Analysis Tool (WHAT)
is a compilation of computer programs that
perform hydrograph separation using three
techniques: (1) local minimum method;
(2) BFLOW filter; and (3) Eckhardt filter (Lim, et
al, 2005).  Each of these techniques is applied
to discharge records for the stream gages listed
in Table 16 for the determination of baseflow
conditions. Details of these techniques and
results follow.

Local Minimum Method (LMM)
Sloto and  Grouse (1996) discuss three meth-
ods of hydrograph separation used in the
HYSEP (HYdrograph SEParation), a baseflow
separation computer package provided by the
USGS. The three methods used in HYSEP to
separate the base flow from the surface runoff
component in a runoff hydrograph are (1) fixed
interval, (2) sliding interval, and (3) local  mini-
mum. Of these three methods, the local  mini-
mum method (LMM), which linearly connects
non-adjacent local minimums of discharge to
derive baseflow, was selected for the WHAT
program. Calculation of the local minimums
is based on a single parameter that is solely
dependent on the drainage area; hence,  hydro-
geologic and  hydrologic basin characteristics
are not properly accounted for and thus may
limit the accuracy of this method (Stewart et al,
2007; Lim et al, 2005). However, this method is
still accepted and is used here. Results for the
selected basins are shown in Table 19.
Table 19.  Baseflow values estimated with the WHAT model using the LMM, BFLOW and Ekhardt techniques.
Site
Number

Site Name

Drainage
area
(mi2)

Period of
record

Local Minimum
Baseflow
Index
fRFH

Baseflow
(in/yr)

BFLOW-single
filter
Baseflow
Index
(RFh

Baseflow
(in/yr)

Eckhardt - dual
filter
Baseflow
Index
(RFh

Baseflow
(in/yr)

State of Tennessee
7030240
7030280
7030295
7030392
7031500
7031650
7031680
7031683
7031685
7031692
7031700
7031740
7032200
7032222
7032224

Loosahatchie River at Arlington, TN
Loosahatchie River at Brunswick,
TN
Tributary to Loosahatchie River at
New Allen Road
Wolf River at LaGrange, TN
Mary's Creek near Fisherville, TN -
tributary to Wolf River
Wolf River at Germantown, TN
Fletcher Creek at Sycamore View
Road - tributary to Wolf River
Fletcher Creek at Whitten Road -
tributary to Wolf River
Fletcher Creek at Charles Bryan
Road - tributary to Wolf River
Fletcher Creek at Sycamore View
Road - tributary to Wolf River
Wolf River at Raleigh, TN
Wolf River at Hollywood Street
Nonconnah Creek near
Germantown, TN
Tributary to Johns Creek at Holmes
Road
Johns Creek at Raines Road -
tributary to Nonconnah Creek

262
505
1.26
210
13.6
699
1.45
21.4
3.18
30.5
771
788
68.2
5.83
19.4

1977-1982
1951-1962
1977-1982
1997-2005
1955-1956
1997-2005
1976-1981
1978-1981
1975-1976
1997-2005
1951-1962
1997-2005
1997-2005
1976-1981
1976-1981

0.36
0.31
0.11
0.62
0.12
0.64
0.08
0.09
0.12
0.11
0.66
0.64
0.16
0.12
0.09

6.39
5.49
2.07
12.82
1.54
13.45
1.73
2.02
2.64
2.79
11.29
14.14
2.58
2.14
1.88

0.43
0.35
0.19
0.67
0.15
0.65
0.15
0.15
0.15
0.16
0.62
0.64
0.21
0.19
0.17

7.64
6.35
3.42
13.74
1.98
13.71
2.99
3.54
3.44
4.27
10.69
14.17
3.40
3.44
3.69

0.43
0.36
0.12
0.64
0.09
0.63
0.08
0.09
0.18
0.19
0.60
0.62
0.12
0.12
0.20

7.61
6.53
2.13
13.15
1.14
13.15
1.74
2.05
4.05
5.03
10.23
13.66
1.92
2.23
4.32

State of Mississippi
7275900
7277700
Coldwater River near Olive Branch,
MS
Hickahala Creek near Senatobia,
MS - tributary to Coldwater River
191
121
1997-2005
1997-2005
0.44
0.37
7.71
7.51
0.51
0.42
8.95
8.62
0.50
0.43
8.81
8.73

-------
BFLOW Filter Technique
Lyne and Hollick (1979) proposed a baseflow
separation technique using low-pass filtering.
Arnold and Allen (1999) subsequently migrated
this technique to a DOS-based program,
BFLOW, later to be incorporated into WHAT
(Lim, et al, 2005). In BFLOW, baseflow is
determined by subtracting a calculated filtered
surface runoff value from the stream discharge
quantity using one day increments.  Calculation
of surface runoff requires only one filter param-
eter (Lyne and Hollick, 1979). Nathan and
McMahon (1990) found that a filter parameter
of 0.925 gave realistic results when compared
to manual separation; hence, this value is used
in this study. Baseflow rates using the BFLOW
technique are shown in Table 19.

        Filter Technique
Chapman (1991) contends that the recursive
low-pass filter proposed by Lyne and Hollick
(1979), though fast and objective, does not
model well baseflow after cessation of direct
runoff.  Chapman also suggests that the filter
constant should expectedly vary by catchment
area.  Eckhardt (2005) showed that the filter
proposed by Chapman (1991) is a special case
of a dual parameter filter that accounts aquifer
and stream type. Eckhardt (2005) proposed
filter values of 0.80 for perennial streams in
porous aquifers, 0.50 for ephemeral streams
in porous aquifers, and 0.25 for perennial
streams in hard rock aquifers. Ekhardt (2008)
conducted a baseflow technique comparison on
a random selection of 65 USGS gages previ-
ously analyzed in a larger baseflow technique
comparison study by Neff et al. (2005), but here
also compared to the technique proposed by
Ekhardt (2005). The streams were perennial
in porous aquifers; therefore, the BFImax filter
parameter was set to 0.80.  Ekhardt (2008)
suggestes that the BFLOW and Ekhardt base-
flow estimate technique produce more realistic
results (baseflow time series is smooth) than
that by UKIH, a local minima technique, and
PART (hydrograph characteristics points are
connected by straight lines).  Ekhardt (2008)
goes on to say that his technique as compared
to BFLOW produces more hydrologically
plausible results.
The Ekhardt filtering technique within WHAT
is applied to the gages list in Table 16.  These
streams are perennial and are in connec-
tion with the unconsolidated aquifers of the
area; hence, a BFImax value of 0.80 is applied.
Baseflow calculations and BFl indexes  for the
17 stream gages are presented in Table 19.

Five different methods were used to com-
pute stream baseflows within the MERGWS
footprint (Table 20).  The computer program,
Analyse-lt™, was used to develop the statistical
understanding of the data. Initially a descrip-
tive analysis was performed that calculated the
mean and standard deviation for the five values
at each gaging station. A box plot analysis
was performed to compare the existing data
with the median and provide quartile informa-
tion. This analysis allowed for the determina-
tion of outliers within the data. As shown in
Table  20, baseflows estimated using partial
duration were consistently below the estimates
from the other methods with the exception of
Fletcher Creek near Cordova; hence, the partial
duration values could be classified as outliers
as compared to the other baseflow values.
Obviously, selection of a  Q60 for the partial
duration analysis does not seem appropriate
and possibly an alternate percent flow dura-
tion threshold may result in more comparable
estimates. Therefore, the remaining analyses
will be performed  using the remaining four
baseflow estimation methods.

The simple statistical analysis was rerun on
the baseflow estimates from the remaining
methods. Table 21 details the average  and
standard deviation for each gaging site. The
average data values indicate a wide difference
in the average baseflows between the drainage
basins, yet a moderate consistency within a
basin.  There are two interesting observations
concerning the baseflows.  First, the baseflow
calculations on the tributaries to the main
streams are much smaller than the calculations
for the main stream. The primary difference in
the smaller drainage basins that were studied
is that they are in  the developing urban areas
and have been subjected to radical clearing
and development  during the overall  period of
study.  Also, the time period for the analysis
was much smaller on the tributaries than on the

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Table 20.  Summarization of baseflow intensities.
Site
Number

Site Name

Drainage
area
(mi2)

Period of
record

Partial
Duration
PART
Local
minimum
BFLOW
(single
filter)
Eckhardt
(dual filter)
Intensity (in/yr)





State of Tennessee
7030240
7030280
7030295
7030392
7031500
7031650
7031680
7031683
7031685
7031692
7031700
7031740
7032200
7032222
7032224

Loosahatchie River at Arlington, TN
Loosahatchie River at Brunswick, TN
Tributary to Loosahatchie River at New
Allen Road
Wolf River at LaGrange, TN
Mary's Creek near Fisherville, TN - tribu-
tary to Wolf River
Wolf River at Germantown, TN
Fletcher Creek at Sycamore View Road -
tributary to Wolf River
Fletcher Creek at Whitten Road - tributary
to Wolf River
Fletcher Creek at Charles Bryan Road -
tributary to Wolf River
Fletcher Creek at Sycamore View Road -
tributary to Wolf River
Wolf River at Raleigh, TN
Wolf River at Hollywood Street
Nonconnah Creek near Germantown, TN
Tributary to Johns Creek at Holmes Road
Johns Creek at Raines Road - tributary to
Nonconnah Creek

262
505
1.26
210
13.6
699
1.45
21.4
3.18
30.5
771
788
68.2
5.83
19.4

1977-1982
1951-1962
1977-1982
1997-2005
1955-1956
1997-2005
1976-1981
1978-1981
1975-1976
1997-2005
1951-1962
1997-2005
1997-2005
1976-1981
1976-1981

5.647
3.172
0.862
10.536
0.998
8.739
1.779
0.761
1.153
1.202
5.986
9.13
0.657
0.792
0.91

-
3.8
1.98
12.84
1.11
12.54
1.43
1.07
1.75
1.81
9.39
13.33
1.85
1.84
1.58

6.391
5.493
2.068
12.815
1.544
13.452
1.727
2.018
2.643
2.792
11.294
14.143
2.579
2.139
1.875

7.64
6.354
3.415
13.741
1.978
13.708
2.993
3.535
3.439
4.27
10.688
14.173
3.399
3.441
3.689

7.609
6.533
2.13
13.154
1.142
13.149
1.735
2.047
4.046
5.033
10.233
13.664
1.92
2.23
4.316

State of Mississippi
7275900
7277700
Coldwater River near Olive Branch, MS
Hickahala Creek near Senatobia, MS -
tributary to Coldwater River
191
121
1997-2005
1997-2005
5.757
5.161
7.36
6.95
7.708
7.513
8.95
8.618
8.811
8.731
main streams; however, no cause and effect
relationship is obvious.

Secondly, the baseflow on the main tributary
of the Wolf River presents some interesting
results.  As shown in Table 21, Station Average
Baseflows with Standard Deviations, the typical
baseflow for three of the gages on the Wolf
River, namely LaGrange, Germantown, and
Hollywood gages, presents the baseflow at
approximately 13+ inches/year. However the
Raleigh gage, which is immediately upstream
of the Hollywood gage, has an average
baseflow of 10.4 inches/year. Bradley (1991)
discusses the loss of streamflow to the alluvial
aquifer proximal to the intersection of Walnut
Grove and the Wolf River; however, the decline
in discharge falls within measurement error
and remains invalidated. Konduru (2007) found
similar results as Bradley, yet was plagued with
the same issue of discharge values falling with
measurement error.  The suggested baseflow
decline at Raleigh on the Wolf River may be
better attributed not to discharge losses, but
be reflective of the basin's landuse condition
during the time of analysis (see Table 16).  In
the early 1950's,  Memphis and Shelby County
had yet to undergo much urban development
and most of the area was agricultural.  A factor
that complicates the estimation of baseflow
also at the Raleigh gage is that the Wolf
River was dredged and realigned from 1960
thru 1964. Thus, it seems logical to omit the
baseflow value at the Raleigh gage. As a
consequence, the average baseflow in the Wolf
River is approximately 13.39 inches/year using
values from the LaGrange, Germantown, and
Hollywood gages.

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For the purpose of the MERGWS effort, it
will be important to capture the recharge and
stream-aquifer interactions across diverse
landscapes and varying spatial and temporal
scales. Baseflow estimates from this investiga-
tion provide insight into the stream/aquifer con-
nection, but on a very general scale and thus
should be used with caution. Additional gages
should only be installed if included as part of a
suite of analysis tools for investigating recharge
and stream/aquifer interactions for the purpose
of validation and ensuring mass-balance.
Table 21.  Average baseflow intensities for MERGWS streams.
Site
Number

Site Name

Drainage
(mi2)

Period of
record

Average
intensity
(in/yr)

Standard
deviation
(in/yr)

State of Tennessee
7030240
7030280
7030295
7030392
7031500
7031650
7031680
7031683
7031685
7031692
7031700
7031740
7032200
7032222
7032224

Loosahatchie River at Arlington, TN
Loosahatchie River at Brunswick, TN
Tributary to Loosahatchie River at New Allen Road
Wolf River at LaGrange, TN
Mary's Creek near Fisherville, TN - tributary to Wolf River
Wolf River at Germantown, TN
Fletcher Creek at Sycamore View Road - tributary to Wolf River
Fletcher Creek at Whitten Road - tributary to Wolf River
Fletcher Creek at Charles Bryan Road - tributary to Wolf River
Fletcher Creek at Sycamore View Road - tributary to Wolf River
Wolf River at Raleigh, TN
Wolf River at Hollywood Street
Nonconnah Creek near Germantown, TN
Tributary to Johns Creek at Holmes Road
Johns Creek at Raines Road - tributary to Nonconnah Creek

262
505
1.26
210
13.6
699
1.45
21.4
3.18
30.5
771
788
68.2
5.83
19.4

1977-1982
1951-1962
1977-1982
1997-2005
1955-1956
1997-2005
1976-1981
1978-1981
1975-1976
1997-2005
1951-1962
1997-2005
1997-2005
1976-1981
1976-1981

7.21
5.55
2.40
13.14
1.44
13.21
1.97
2.17
2.97
3.48
10.40
13.83
2.44
2.41
2.87

0.71
1.25
0.68
0.43
0.41
0.50
0.70
1.02
1.00
1.45
0.80
0.41
0.72
0.71
1.34

State of Mississippi
7275900
7277700
Coldwater River near Olive Branch, MS
Hickahala Creek near Senatobia, MS - tributary to Coldwater
River
191
121
1997-2005
1997-2005
8.21
7.95
0.79
0.87
Riverbed conductance
There are a number of factors that govern the
exchange of flow between a river and ground
water.  Such factors would include ground-
water levels, river stage, riverbed conductance,
bank storage capacity, throughflow seepage
contribution, and others.  Past studies in the
area have used a combination of ground-water
levels, river stage and riverbed conductance to
numerically  model ground-water/surface water
exchange (Arthur and Taylor, 1990; Mahon
and  Ludwig, 1990; Mahon and Poynter, 1993;
Waldron, 1995; Arthur and Taylor, 1998).  In
these models, riverbed conductance was esti-
mated and set as a constant for the entire river
length.  Other local studies have used river
discharge variation to suggest the exchange
of water between  the two systems (Bradley,
1991) and ground-water age-dating to suggest
leakage (Graham and Parks, 1986).  To further
our understanding on the potential for ground-
water/surface water interaction, we assess
riverbed conductance using borehole data from
geotechnical logs at bridge/river crossings.

The analysis of riverbed conductivities  is lim-
ited to bridge crossings over the Loosahatchie
and Wolf Rivers and Nonconnah Creek. Due
to time constraints, the Hatchie and Clearwater
Rivers were not investigated. Data acquisi-
tion from the Tennessee Department of
Transportation and local engineering firms
included sieve analyses, boring logs and loca-
tions, and geotechnical reports.  Based on the
historic records available, eight crossings were
identified in Shelby County and four in  Fayette
County (Figure 62 and Table 22).

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                        90°0'0"W
89°30'0"W
  35°15'0"N-
                               -35°15'0"N
                        90°0'0"W
           I   i    I   'I   i   i   i   !
           0     5     10          20 Miles
89°30'0"W
  Legend
                                                                          Geotechnical boring location
                                                                          Major river
                                                                          Major roads
                                                                          County
Figure 62.   Bridge crossing locations investigates for geotechnical information on riverbed parameters.

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Table 22.  Shelby and Fayette County, Tennessee bridge crossings investigated for geotechnical information
          on riverbed parameters including an estimation of riverbed conductance.
Crossing
SR14
SR3
Walnut Grove
Proposed SR
385 (SR 57 to
SR 193)
Near
Riverport
Airways Blvd.
Knight Arnold
SR175
SR194
SR57
McKinstry Rd.
SR76
River
Loosahatchie
Wolf
Wolf
Wolf
Nonconnah
Nonconnah
Nonconnah
Nonconnah
Wolf
Wolf
North Fork
Wolf
North Fork
Wolf
County
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Fayette
Favette
Fayette
Fayette
Boring Logs
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Boring
Locations
Y
Y
N
N
N
Y
Y
N
N
N
N
N
Sieve Analysis
N
Gradation
Curves
N
Gradation
Curves
Gradation
Curves
Gradation
Curves
Gradation
Curves
Y
N
Y
Y
Gradation
Curves
Complete
Geotechnical
Report
N
Y
N
N
N
N
N
N
N
N
N
N
Boring logs
used
BR-18, BR-
19, BR-20,
BR-23, BR-24
BR-7, BR-8,
BR-12, BR-13
BB-23, BB-26,
BB-29
N/A
B-1, B-2, B-
12
B-1,B-2
B-6, B-7, B-8
WA
B-1 , B-2
B-1,B-2, B-3
B-1, B-2
B-1, B-2
Estimated
K using
uses
(m/day)
>0.864to
0.00000864
0.864 to >
0.864
0.00086410
0.00000864
N/A
> 0.864 to
0.000864
> 0.864
>0.864to
0.000864
N/A
0.864 to
0.00000864
0.864 to
0.000864
0.00086410
0.00000864
0.86410
0.000864
Estimated
K using
empirical
formulas
(m/day)
N/A
14.6510
19.53
N/A
N/A
N/A
N/A
N/A
N/A
N/A
1.03 to 1.09
1.09102.93
N/A
Comments

Empirical estimate is
based on BR-12 and
BR-13 gradation
curves.

Location information
on the borings could
not be found.
Em pineal estimate
could not be made
Decause the gradation
curves were not
available at the
desired depth
Em pineal estimate
could not be made
Decause the gradation
curves were not
available at the
desired depth
Empirical estimate
could not be made
because the gradation
curves were not
available at the
desired depth
Location information
on the borings could
not be found.



Empirical estimate
could not be made
because the gradation
curve records were
incomplete
 Hydraulic conductivity was calculated using the
 Unified Soil Classification System (USCS) and
 empirical formulas (Kasenow, 2002) based on
 soil types and grain size analyses (or gradation
 curves), respectively. The empirical formulas
 include Geotechnical reports and supplemental
 borehole information was used to isolate those
 boreholes closest to the river.  Elevation data
 from USGS NED's or Lidar was used to ascer-
 tain approximate riverbed elevations, unless
 otherwise stated in reports, to correlate with the
 corresponding borehole log soil interval depths.
 It is the soil properties at these depth intervals
 that an estimate of hydraulic conductivity was
 calculated.
The six empirical equations used to estimate
hydraulic conductivity are Beyer, Hazen,
Kozeny, Sauerbrei, USER (United States
Bureau of Reclamation), and Pavchich.  Each
empirical formula was setup for different
conditions but all meant for  use with uncon-
solidated sediment, primarily sand and gravel
(Kasenow 2002).  In the software package that
executes the empirical calculations, the water
temperature was set at 10°C.  The geotechni-
cal boring records that include sieve analyses
show a percent fine for clays.  The Number 325
sieve was selected in the software package
to represent clay fines as a  Number 200 was
not an  option. The average of the six empirical

-------
equations was used to represent the riverbed
hydraulic conductivity value.

The estimates of riverbed conductance using
the USCS method are not comparable to the
estimates obtained from the empirical formulas.
This is understandable as the USCS values
are generalized, based  on the characterization
of the soil, and the empirical formulas are tied
more closely to the soil composition (grain
size).  As shown in Table 22,  USCS estimates
for a single site may vary as much as three
to five orders  of magnitude (e.g., SR14,  Near
Riverport, SR 76).  To explain this varied range
in USCS estimates, one must realize that:
(1) the geotechnical boring locations are all
proximal to the river, but not in the river; (2) riv-
erbed elevation is projected horizontally to the
boring and  intersected with the soil stratification
column  (see Appendix Geo-sites);  and (3) all of
the boring locations fall within the alluvial plain
which results  in a complex buried stratigraphy
comprised of  point bars, oxbows, channel infill,
etc.

Only three sites had enough information to
estimate riverbed conductance using the
empirical formulas (Table 22). SR  3 is close
to the confluence of the Wolf River and the
Mississippi  River (Figure 62). The correlated
stratigraphy of two SR 3 borings, BR-7 and
BR-8, with the riverbed  elevation is near
surface resulting in loose, medium grain sand
and some rip-rap (excluded from the grain size
analysis) (see Appendix Geo-sites). BR-12
indicates sand with gravel, and BR-13 shows
sand with some silt. These conditions explain
the high riverbed conductance as compared to
the other two  sites, SR 57 and McKinstry Road.
At SR 57, the correlated soils of B-1, B-2 and
B-3 with the riverbed elevation are all near
surface, resulting in a silty soil. In this area,  the
Memphis Sand outcrops thus explaining the
prevalence  of sand beneath the surface (see
SR 57 in Appendix Geo-sites).  The estimate
of riverbed  conductance at SR 57 (1.03  to
1.09 m/day) is comparable to that estimated
at McKinstry Rd. (1.09 to 2.93 m/day) using
the empirical formulas.  The estimates can
be considered to be comparable due to their
close proximity to one another and because
the correlated stratigraphy intervals are all
near surface and thus may be representative
of similar geomorphologic processes and
deposition. The correlated soil type for BR-1
at McKinstry is clay with a description of gray/
silty (Appendix Geo-sites). Using the USCS
method, the riverbed conductance is estimated
to be between 0.000864 and 0.00000864 ml
day. However determining the conductance
using the empirical formulas and the grain size
data resulted in a much higher estimate, 1.09
m/day. This discrepancy between these two
methods illustrates the importance of using
detailed soil data (e.g., grain size analysis)
versus generalizing conductance from soil type.
The estimate at BR-1  closely approximates the
estimate at BR-2 of 2.93 m/day.

Use of the  USCS method to estimate riverbed
conductance should be used with caution.
Obtaining grain size analyses of the riverbed
bottom should provide a close estimate of
conductance; however, the boundary condi-
tions and initial assumptions for the equations
were assumed and the authors of the formulas
do not normally recommend criteria for their
use (Vukovic and Soro, 1992).  This adds
to the uncertainty of the estimated riverbed
conductance values derived from the empirical
formulas.  In situ measurements of riverbed
conductance would provide a better estimate
of conductance, and the results can be supple-
mented with those estimates derived from grain
size analyses  provided assumptions can be
justified. We speculate that determination of a
static riverbed conductance may prove dif-
ficult as geomorphic processes are constantly
changing the river structure, especially in the
channelized sections of river where bank failure
is common. Where in situ measurements are
useful for a site specific investigation, a range
of conductance values will better serve large-
scale applications such as when developing a
regional ground-water model.

 Wetlands
Wetlands are known to have an interactive
role with the local ground-water and other
surface water  systems; however, specifically
what that connection is, is unknown due to
the lack of research on this topic in this area.
Therefore this subtask focuses specifically on

-------
the availability of digital wetland mapping for
the area.  Here, digital data is considered to be
in CIS format, not scanned images of maps or
spreadsheet data.

Wetland information is available through the
US Fish and Wildlife (FWS) National Wetland
Inventory  (NWI) program.  The FWS office in
each state is  responsible for the digitization of
wetland data  into a digital format, this format
often being in a CIS. Figure 63 shows the NWI
digitization status across the study area.  This
information is available through the  FWS NWI
metadata  listing at http://www. fws.gov/wetlands/
data/Mapper.html.  Though the metadata layer
in Figure 63 does not extend into the northern
section of Tipton County, TN, and the eastern
section of Hardeman County, TN, these areas
are listed  as non-digital on the FWS NWI
metadata  website.
                              Legend

                              I   I county
                              NWI wMlind metadata
                              stuut or digital Milaum?


                                 Non-Digital
                                 Scan
Figure 63.   Status of wetland digitization based on
            NWI metadata from the US FWS.
Wetland data was downloaded from the
national US FWS website (http://www.fws.
gov/wetlands/index.html) for Mississippi and
Arkansas.  Wetland data for Tennessee was
accessible through this same site; however, the
FWS office in Tennessee hosted digital wetland
data for the four counties in Tennessee for
areas listed as non-digital on the national FWS
website. This discrepancy between the national
and Tennessee FWS office on available digital
wetland data can be seen in Figure 64 where
non-digital and scanned areas (national  FWS)
overlap areas where wetland data exists (state
FWS office).  Reasons for this  discrepancy are
unknown. Wetland classification for the digital
data collected follows the National Wetlands
Classification standard (Cowardin et al.,
1979).  A timeline for converting the non-digital
and scanned area wetland data into CIS is
unknown.
                                                                                Legend

                                                                                I  [County
                                                                                  | Noo-dignal or 5
Figure 64.   Discrepancy between the national and
            Tennessee FWS office on available
            digital wetland data.

Soil data
Soil survey maps and data  may be important
and useful with regards to assessing aquifer
recharge, water infiltration,  and site  location
information.  Soils are typically derived in situ
from the materials in place, so that soils may
be reflective of the underlying materials and
indicative of material property.  Utilizing soil
survey data  may aid in several aspects of this
project in the future by providing indicators that
may help in  quantifying infiltration rates,  iden-
tifying variability in underlying geologic forma-
tions, identifying sites that could be  useful for
field study, and a  variety of  other applications.
These data sets may also yield proxy informa-
tion about the aquifers themselves, indicating
changes in grain size, distribution, extents,
latent heat assessment, and other pertinent
information.  Data assessments are made from
two scales, 1:12,000 and 1: 1:250,000.

For each county, soils data  comprised of
ArcGISŪ shapefiles  and Microsoft AccessŪ

-------
tabular databases were acquired from the
United States Department of Agriculture
(USDA) through the Natural Resources
Conservation Service (NRCS)
(http://soildatamart. nrcs. usda.gov).

Pertinent data to the study within the tabular
data were exported by generating a series
of reports from within the Microsoft Access
databases. These tabular reports, in the form
of individual Microsoft Excel sheets, were
joined with their corresponding shapefile using
the identifier  keys within each dataset. The
shapefile contained only the shape of the unit
and a unique identifier. The tabular  dataset
contained all  available information about the
units  and types correlated to the soil name and
a unique identifier. The unique identifiers were
used  to join the tabular data to the shapefile
data.  The resulting dataset has both the spatial
extent of the  data as well as all the tabular data
available for query and interpretation. The data
from each county were imported into a single
CIS environment for display and interpretation.

Soil survey data is typically generated by a
group of individuals that combine field-based
and aerial photography (remote sensing)
mapping.  Field investigation provides for soil
pit analyses,  determination  of the  proper soil
class, taxonornic characterization, grain size,
and other characteristics of the soil and flora.
Typically, counties are not mapped by the
same individuals, and mapping differences can
lead to significant variability between county
soil maps when performing detailed  analyses.
Examples of  this variability  include delinea-
tion of a particular unit in one county that is
not identified in an adjacent county despite its
presence.

Given the differences in the soil survey map-
ping techniques, the county data was not
merged into a single shapefile database. This
was done to  preserve the individual  county data
integrity and  to make management for visual
investigation  and manipulation more simplified.
The county datasets can be merged at a later
data upon further analysis.  The data analyzed
describe taxonornic characterization of particle
size and soil  names. Soil names were not
modified, but presented as  found within the
soil survey tabular data. Joining or displaying
tables directly by their original descriptions was
impractical as no apparent continuity of data
was present and the variable nomenclature
increased mapping complexity. Thus, edge
matching between counties of the grain size
polygons was performed visually to enhance
continuity of similar textures and soil units.

The 1:12,000 scale maps at the county level
provide high resolution data that may be useful
in assessing potential ground water recharge
areas.  These datasets may provide informa-
tion relating to recharge and infiltration rates
of the aquifer, as well as land cover and land
use practices. The derived  surface area of
infiltration may also allow significant interpreta-
tion with regard to ground water recharge and
sedimentary unit (aquifer) distribution.  Ground-
truthing of these data should be conducted to
assess their accuracy and hence, their utility.
Dissected Loess overlies the primary recharge
location of the Memphis Sand aquifer (Plate 8).
The impact of this dissected loess blanket over
such a broad region of the Memphis aquifer
recharge area on  ground-water recharge will
need to be investigated further.  Additionally,
distribution of sandy soils may be used  as a
proxy for  outcrop of the Memphis Sand  aqui-
fer and direct recharge to the ground water.
Correlation of soil type and  soil property with
MODIS and  Landsat data may be helpful  in
determining  evapotranspiration and recharge
factors.

The 1:250,000 scale maps are based upon
the statewide maps. Though not as detailed
as the 1:12,000 scale county soil maps, the
regional data provides a general description
of the soil properties.  This more generalized
data may  be useful in assigning parameters to
a broader region that is useful at the map scale
of the geology and aquifer maps/models.  The
soils maps may help refine  the surface geology
maps providing contact information and further
sedimentary fades information (Plate 9).  As
expected based on analysis of the 1:12,000
scale soil  maps, combination of the state soil
maps for  Arkansas,  Mississippi, and Tennessee
yielded inconsistencies in the naming and
distribution of materials that will require further
work to correct.

-------
                                    of
      to the
Two additional stressors to the ground-water
system are assessed under this effort, they
being recharge and evapotranspiration.
Recharge is defined as the natural process of
infiltrating rainwater replenishing the ground-
water system.  Recharge, in a broader sense,
can include contributions from surface water
and aquifer leakage through aquitards; how-
ever, these mechanisms of recharge have been
addressed in prior sections. Evapotranspiration
represents a loss of water from the system
through the combined effect of evaporation and
plant transpiration.

                                 for

Recharge is a  critical variable for water-
balance within a hydrologic basin, and is thus
an essential quantity for evaluating long-term
ground-water resource sustainability and qual-
ity. Recharge studies have generally focused
on arid and semi-arid regions, where water
resources are  most scarce and recharge is
most influenced by near-surface conditions
(de Vries and Simmers, 2002).  Recharge
processes have been addressed to a lesser
degree in humid regions (Rushton  and Ward,
1979; Sophocleus and Perry, 1985; Wu et al.,
1996). Furthermore, recharge estimation in
humid regions has focused more on regional-
scale estimates, either from water-balance
models (see review in Lerner et al., 1990)
or ground-water flow models (see review in
Sanford, 2002). However, to address issues
such as focused recharge and land-use
impacts on recharge, point or local-scale
values of recharge integrated over  varying time
intervals are necessary (Scanlon et al., 2002).
Common point-methods of recharge estima-
tion employed  in humid environments include:
Soil-water balance (e.g., Richards et al., 1956;
Rushton and Ward, 1979), Lysimeter measure-
ments (e.g., Kitching and Shearer,  1982), Darcy
flux (e.g., Steenhuis et al., 1985), environmen-
tal tracers (Allison and Hughes, 1978; Edmunds
et al., 1988), historical tracers (see review
in Cook and Bohlke, 2000), and water-table
fluctuation methods (see review in  Healy and
Cook, 2002).  Each of these methods has spe-
cific spatial and temporal sensitivity; however,
environmental tracers, especially chloride, offer
great promise for resolving recharge at a wide
range of spatial and temporal scales (Scanlon
et al., 2002) and have been underutilized in
humid settings.

Environmental tracers offer the opportunity to
finely quantify recharge spatially and temporally
over an area.  The utility of tracers in estimating
recharge has  been demonstrated in arid and
semi-arid environments, where the water-bal-
ance approaches are inapplicable (Allison and
Hughes, 1983; Gaye and Edmunds, 1996).  In
this setting, recharge rates are relatively small
compared to the measurements of precipitation
(P) and evapotranspiration (ET). As a result,
small errors associated with measurement of P
and ET lead to large recharge estimation errors
(Gee and Hillel, 1988; Walker et al., 1991;
Phillips,  1994; Wood, 1999) and limit the utility
of soil-water balance methods. Application of
environmental tracers to determine recharge
through the vadose zone have included chlo-
ride, 18O and 2H, and the radioactive isotopes,
tritium and 36CI (Allison  and Hughes, 1978;
Sharrna and Hughes, 1985; Daniels et al.,
1991; Cook et al.,  1994; Reilly et al., 1994; Lui
et al., 1995; Wood and Sanford, 1995; O'Brien
et al., 1996; Rosen et al., 1999), with chloride
and tritium being the most common tracers
used.

Defining of aquifer recharge areas within the
region is illustrated by Williamson et al (1990)
(Figure 65). As seen in Figure 65, West
Tennessee is  the major recharge zone for the
Claiborne and Wilcox aquifers.  Unfortunately
within the study area, few investigations have
estimated the rate of ground-water recharge.
Of those estimates that exist, the majority
are  derived recharge rates from numerical
models,  but without physical validation. In
a numerical modeling study of groundwater
flow in the Mississippi embayment, Arthur and
Taylor (1998)  determined a spatially averaged
recharge rate of 1  in/yr. McKee and Clark
(2003) simulated aerial  recharge rates to the
Memphis aquifer in their numerical model of
ground-water  flow in southeastern Arkansas
and north-central Louisiana. Their model

-------
calibrated rates ranged between 0.12 and
1.1  in/yr. Brahana and Broshears (2001),
using a numerical groundwater flow model in
the Memphis, Tennessee area, determined
a recharge rate of 0.16 to 1.42 in/yr for the
Memphis aquifer recharge area.  Bailey et al.
(1993), in their numerical ground-water model
of Jackson, Tennessee, estimated recharge
rates in the Memphis and Fort Pillow aquifers
outcrop area using measurements of Q60 for
two rivers crossing the region. These rates
ranged between 5.7 and 8.1  in/yr with  model
calibrated values averaging around 9.0 in/yr.
An investigation by Waldron (personal  com-
munication) used  meteoric chloride as a tracer
within the vadose zone in Fayette County,
Tennessee, following recharge estimation
procedures commonly implemented in arid
environments (Allison and Hughes, 1978; Cook
et al., 1994; Sukhija et al., 1996).  They esti-
mated recharge to occur  at 0.64 in/yr;  however,
analysis of chloride in ground water resulted in
a rate of 5.9 in/yr. Such differences between
the two methods are commonly encountered
with this method, especially in situations of
higher recharge rates (Wood, 1999; Scanlon et
al.,  2002). Despite the difference in recharge
rates obtained by Waldron et al, values
are generally within the range of estimates
obtained using aforementioned methods in the
region.  Emphasis should be placed on the
need to assess spatial and temporal scales
when estimating recharge rates.  No one single
recharge estimation technique will work in all
situations; hence, a suite of methods (water
balance, lysimeters, tracers, etc.) should be
employed.
    o  n   so      itŧ MM   Legend
                         VWteox recharge area

                       I  | Mississippi E/nbaymerrt
                       I  | Sl*w boundary
                         I Study area

Figure 65.   Delineation of Middle and Lower
            Claiborne and Wilcox recharge areas
            within the Mississippi Embayment.
Evaluate methods for estimating
evapotranspiration
Evapotranspiration is the combined sum of
evaporation and plant transpiration. Together
they represent a significant water loss from
a watershed.  These two sources account for
water reaching the ground that is then lost back
into the atmosphere,  through soil processes,
leaf canopy transpiration, and surface water
evaporation. The principal factors affecting
and driving evapotranspiration are radiation, air
temperature, humidity, and wind speed.

In addition to soil water content and hydraulic
conductivity, soil evaporation is mainly deter-
mined by the fraction of solar radiation reaching
the soil  surface. This fraction is decreased by
the presence and density of plant cover, which
primarily loses water through transpiration,
thus both soil and vegetation types significantly
impact the relative water loss rates. Accurately
gaging ground water recharge and losses
requires the quantification of evaporation,
transpiration,  and infiltration rates, all  of which
require the measurement of multiple variables.

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Water loss due to evapotranspiration is poorly
known and quantified within the study area.
The variability of this component of the water
cycle is of critical importance and needs to be
assessed to ensure correct model parameters
are used for ground water flow modeling
(Brahana and Broshears, 2001). To date, few
systems are in place to estimate evapotranspi-
ration within the study area.

Evapotranspiration can  be  measured, but not
directly by any method.  Accurate and precise
data must be derived from  several types of
data such as heat flux, soil moisture retention,
CO2, water vapor, and other flux and trace
gas measurements (Brotzge and Crawford,
2003).  Quantifying evapotranspiration is a
complex process requiring  a number of fac-
tors, algorithms, and assumptions that must be
made that vary based upon the estimation or
measurement method employed.  Regardless
of the methodology employed, several empirical
relationships and constants must be estab-
lished and known, given the conditions under
which measurements are being made.

There are three general approaches to estimat-
ing evapotranspiration: (1) satellite derived;
(2) site measurement; and  (3) a combination
of the two. Assumptions and algorithms vary
depending upon  the method, equipment,
resolution, and datasets used. Two primary
methods for  calculating  (estimating/measuring)
evapotranspiration are herein considered for
their usefulness and application in this study;
these shown in Table 23.
Table 23.  List of evapotranspiration estimation
          methods.
Evapotranspiration Measurement/Estimation Methods
Point
Measurements
Remote Sensing
Measurements
Weather station (using Penman-
Monteith method ( Monteith, 1965)
Bowen Ratio measurement (Using
Bowen Ratio estimation method,
Bowen, 1926)
Eddy Covariant Method (using
Eddy Covariant Correlation
Coefficient)
MODIS Evapotranspiration
estimates
Landsat Heat Flux Proxies for
Evapotranspiration
rGIS-et GIS tool (using a com-
bination of MODIS and Landsat
datasets with ground truthing
performed onsite)
Physical sampling methods
Point measurement/estimation systems rely
on microclimate towers, typically 2-3 meters in
height, prepositioned at a particular location of
interest, which can be used to measure some
or all of the necessary parameters needed
to quantify evapotranspiration at that loca-
tion. Unmeasured variables are estimated or
input from user-defined parameters. Sampling
site footprint size will be nearly identical for
each method type,  as all point measurement
systems employing microclimate towers are
influenced by similar fetch variations from
nearby vegetation.  Site variability is important
and must be understood and included into the
methodologies. Not all sites are applicable
to these methodologies as irregular footprints
or close proximity to tall forests will impact
measurements. Variables such as soil type,
solar incidence angle, land cover, microclimate,
wind, vegetation type and mass, and other
factors can drastically alter evapotranspiration
estimates from site to site (Allen et al., 1998).
Land cover is important to the measurement as
each land cover type or land use type has a dif-
ferent crop  coefficient that must be used in the
evapotranspiration calculation.  Further, each
soil type will have different moisture transfer
and storativity properties that must be included
into the measurements and/or the assumptions
used in the equation (Brotzge and Crawford,
2003).  Micrometerological sampling methods

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have significant advantages over lysimeter and
soil moisture sampling methods in that they do
not require significant manpower and attention,
can be employed and readily moved, they can
be used for short or long durations, and they
provide constant flux measurements (Fritschen,
1965).


Simple weather station derived evapotranspira-
tion estimates are possible using the Penman-
Monteith equation. This method entails the
measurement of daily mean temperature, rela-
tive humidity, wind speed, and solar radiation
(Monteith,  1965).  These measurement param-
eters are sensitive to physical conditions in the
area such  as land cover, NDVI (normalized
difference  vegetation index), and vegetative
indices (e.g., stomata resistance and conduc-
tance). The Penman-Monteith method utilizes
the crop coefficient that best emulates vegeta-
tion site conditions. This methodology requires
assumptions related to the energy heat fluxes
to complete the calculation of evapotranspira-
tion, thus forcing closure of the energy budget
(Monteith,  1965).

The modified Penman-Monteith equation is a
preferred evapotranspiration estimation  method
by the Food and Agriculture Organization of
the United Nations (UN FAO) for estimating
cropland evapotranspiration over a wide variety
of vegetative indices, available crop types, and
instrumentation data on weekly or monthly time
steps (Allen, et al., 1998).  Allen and others
(1998)  found that the more simplistic approach
and application of the Penman-Monteith
equation often produced erroneous results in
estimating evapotranspiration in anything other
than the reference crop used  to parameterize
the equation. The usefulness and accuracy of
this equation can be improved with the physical
measurement of the heat flux variables  (Allen,
et al., 1998). They realized that the method
could be much improved when a local wind
calibration was performed, the local aerody-
namic term remained relatively small, and
where detailed temperature measurements of
the near surface ground height and soil were
performed. The American Society of Civil
Engineers  (ASCE), UN FAO,  and European
counterparts have found that by providing
more site specific higher resolution data, the
Penman-Monteith equation can be applied
successfully (Allen et al., 1998). Benefits of this
method include its relatively low cost, ability
to account for common different crops and its
ease of application.


The Bowen ratio  (B) equation is used to
estimate evapotranspiration through calculating
the ratio of energy fluxes between mediums,
specifically sensible (potential energy) and
latent (amount of energy released) heating;
hence B = Qh/Qe where Qhis sensible heating
and Qe represents latent heating (Bowen, 1926;
Lewis, 1995). To estimate evapotranspiration,
sensible and latent heat fluxes are derived
through measurements of surface net radia-
tion, temperature, total soil heat flux, and vapor
pressure between two points. Such measure-
ments are typically conducted at heights of 2
to 3 rn; however,  up to 10-rneter heights can be
used for larger site footprints or to reach above
forest canopy (McNeil and Shuttleworth, 1975;
Brotzge and Crawford, 2003).  Rather than
measuring all components of the energy cycle,
the Bowen ratio method forces closure of the
energy budget as the eddy diffusivities of heat
and moisture are assumed to be equal. Forced
closure of the energy budget makes the Bowen
ratio method easier to employ, decreases
measurement complexity,  increases instru-
ment simplicity, and is typically less expensive
than Eddy Covariance methods.  Estimates by
McNeil and Shuttleworth (1975), Shuttleworth
and others (1984), Dugas and others (1991),
and Brotzge and  Crawford (2003) suggest
Bowen ratio measurements may overestimate
the evapotranspiration in some environments
and vegetation types; the biggest concerns are
found  within arid  environments. Detractions to
the method are that closure is forced and the
eddy diffusivities  of heat and moisture must be
assumed equal (Brotzge and Crawford, 2003).

Eddy
Eddy Covariance is an evapotranspiration
measurement technique where the energy bal-
ance is closed through flux measurement rather
than assumption  (Dugas et al., 1991; Brotzge

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and Crawford, 2003). The Eddy covariance is
computed as the covariance between instan-
taneous variation in vertical wind speed from
the mean value and instantaneous deviation in
gas concentration mixing ratio from its mean
value; these are then multiplied by the mean
air density (Burba and Forman, 2008). This
technique is extensively employed for valida-
tion and tuning of global climate models and
regional satellite estimates (Mu et al., 2007).
Detractions to the Eddy Covariance method
typically include the increased complexity
and number of instrumentations and high
cost compared to the Bowen ratio method.
Continued demand for this technique is result-
ing in improvements in instrumentation and a
reduction in cost.

Eddy covariance is more sensitive to local
conditions such as fetch and wind direction
(Brotzge and Crawford, 2003).  Benefits of the
method stem from true closure of the energy
budget by measuring the four component fluxes
of the energy budget rather than assuming or
forcing closure (Brotzge and Crawford, 2003).
Another advantage of the method is that failure
to close the energy budget through measure-
ments provides a real-time quality control on
evapotranspiration values and thus  possibly
improper working of the instrumentation.

Comparison of Point Measurement Systems
As discussed, there are advantages and
disadvantages to each type of point measure-
ment system. There are arguably variations in
accuracy and reliability of the methodologies,
suggesting each has its place in its intended
application.  All three proposed methodologies
are: (1) accepted within the scientific com-
munity; (2) considered reliable; and (3) not
cost prohibitive. Comparison of these and
other factors for the three point measurement
techniques are shown in Table 24. All point
measurement systems (microclimate towers)
require several design requirements/assump-
tions: (1) the point measurement represents
the upwind area from the instrumentation;
(2) measurements are performed within the
selected site set to a  height above the domi-
nate vegetation type of interest at the site while
avoiding influence by nearby vegetation; (3) the
fetch terrain is relatively uniform, flat lying or
has a consistent slope; and (4) any assump-
tions made on local variables remain constant
throughout the sampling period.

Satellite/Remote Sensing Sampling Methods
Remote sensing is another way to estimate
evapotranspiration. Typically this is performed
via satellite; however, it may not be solely a
satellite derived product and often requires the
use of ground-based  point measurement data
to derive evapotranspiration and other products
(Mu et al., 2007).  Instrumentation aboard the
NASA Aqua AIRS, CERES, and MODIS satel-
lites provides sufficient input data to calculate
evapotranspiration.

MODIS/Landsat
Remote sensing estimates of evapotrans-
piration  derived from satellite-based instru-
mentation are available from the Center
for Space and Remote Sensing Research.
Evapotranspiration available from MODIS data
is processed following Mu et al (2007). Cleugh
et al (2007) noted deficiencies in previous
satellite derived estimates and generated a
new algorithm that better matched ground truth-
ing stations for a variety of land cover types.
Table 24.  Comparison of point measurement evapotranspiration methods.
Point Measurement/Estimation Comparison
Method
Weather Station
(Penman-Monteith)
Bowen Ratio Method
Eddy Covariance
Method
Assumptions
Several
Few
None
Accuracy
Moderate
Average to high
High
Cost
Low
Medium
High
Pros/Cons
Easiest, most reliable, and robust
least accurate
Moderate ease of use, moder-
ate cost, High Accuracy, some
assumptions
Highest Accuracy, full measure-
ment of the energy budget

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Mu et al  (2007) based their work on the work
of Cleugh et al (2007) to include and calculate
canopy conductance and evapotranspiration
to generate the current MODIS evapotrans-
piration data.  The MODIS  data set utilizes
an algorithm that considers both the surface
energy partitioning processes and environ-
mental constraints on evapotranspiration.  The
MODIS dataset also uses 19 ground-based
meteorological observations (AmeriFlux Eddy
Covariance flux towers) tied to remote sensing
data from MODIS to estimate global evapo-
transpiration. Mu  and others (2007) cite an
improvement of the correlation coefficients from
0.70 to 0.76 with  the inclusion of tower derived
meteorological data as opposed to just using
satellite-derived data.  Evapotranspiration is
calculated  by Mu and others  (2007) by adding
vapor pressure deficit and  minimum air tem-
perature  constraints on stomatal conductance,
using leaf area index as a scalar for estimating
canopy conductance, replacing the NDVI with
the Enhanced Vegetation Index thereby also
changing the equation for calculation of the
vegetation cover fraction, and adding a calcula-
tion for soil evaporation.

The available datasets are eight day aver-
ages of the evapotranspiration variations
presented within a 1-km (0.62-mile) resolution
grid. Benefits to the method are ease  of use,
the data is available in a CIS projected raster
format and no cost.  Detractions to utilizing this
data are lack of control towers currently avail-
able within or near the MERGWS study area
(Figure 66),  and the evapotranspiration esti-
mate is subject to cloud interference requiring
the use of the previous cycle's data to  complete
the derivation of evapotranspiration.
      140'0'O-W
                            120°0'0"W
                                               100°0'0"W
                                                                  80°0'0"W
                                                                                    60°0'0"W
         Pacific Ocean
        120°0'0"W
                                       100°0'0"W
                           1,000 Miles
                   80°0'0"W
            Legend

            •fr Evapotranspiration Ground Truthtng Stations Mu et al. (2007)

              | Defined study area
                                                                 Major Lakes
Figure 66.   Location of evapotranspiration control towers proximal to the study area

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Landsat datasets illustrating relative heat
flux measurements from a twice-daily pass
may also aid in assessing evapotranspiration
variability within a small area by measuring
heat flux variability before and after storm
events.  Heat flux variability after storm events
may be helpful  in assessing where small-scale
changes in soil, slope, and land cover variability
(including seasonal changes) exist within a
particular site or may yield clues as to which
sites are intrinsically more variable than others.
Applicable Landsat datasets are available
at higher resolution (60 m and 250 m) and
frequency (daily) than MODIS data.  Several
European satellites that are taking measure-
ments over the United States may provide addi-
tional data toward estimating evapotranspiration
across the MERGWS study area.  Presently,
only MODIS data appears to have evapotrans-
piration estimates as a product.

rGIS-et
rGIS-et is a CIS-based tool that utilizes both
satellite MODIS, Landsat datasets and ground
truthing stations of winter wheat and/or summer
maize fields to estimate evapotranspiration.
This tool is designed to allow the rapid process-
ing  of large amounts of satellite data to yield
250 m  resolution evapotranspiration raster data
sets on a daily basis. The tool is designed
to be user friendly and a direct plug-in into
ESRI'sŪ ArcGIS Desktop software.  Surface
temperatures and albedo are key parameters
in calculating evapotranspiration utilizing a
surface energy balance algorithm (Shu et al.,
2006; Yuping et al., 2006). Yuping et al (2006)
added  a module to rGIS-ET (v2.0) allowing
for the adjustment of surface temperature and
solar radiance  and providing a capacity for
terrain  correction and shaded relief to improve
the  estimate of evapotranspiration.  Benefits to
this method include higher resolution data over
shorter time intervals as opposed to eight-day
intervals. Ground-truthing will be problematic
as these modules are currently tied to the
previously mentioned ground-truthed crop
types and the climate of present application
(southern China); however, the algorithm could
be modified to  a different latitude and crop type.
Detractions also include a non-standard and
non-widely accepted methodology for calculat-
ing  evapotranspiration.
Land Cover
Land cover/vegetation type is a primary factor
necessary by design when assessing evapo-
transpiration for a location. Land cover/vegeta-
tion types and their distributions found through-
out the study area are displayed in Figure 67.
Sampling site locations that are at least 1 km2
in area and of relatively uniform shape are
recommended for successful implementation
of the point measurement  methods. To employ
any point measurement system, it is necessary
to understand  and quantify the land cover/vege-
tation distribution and attain evapotranspiration
estimates for each land cover subtype based
upon distribution and area. A more accurate
and complete understanding and assessment
of evapotranspiration can be achieved through
distributed modeling of evapotranspiration with
land cover/vegetation type, which in turn can be
used to calculate one of the key factors in the
overall hydrologic water cycle budget.

The method employed to identify land cover
locations suitable for this study was performed
within ESRI'sŪ ArcGIS utilizing 2001 land
cover datasets. Given the necessity of a large
upwind area of a like vegetation type, polygons
of Yz mi2  and greater were  delimited for each
land cover type.  Refinement of plausible instru-
mentation deployment sites was performed
based on a site's shape uniformity (i.e., elimina-
tion of irregularly shaped areas).  Irregularly
shaped areas were culled  out by calculating an
ideal perimeter for the land cover polygons by
taking the square root of the calculated area
and multiplying that value by four.  This ideal
perimeter was compared to the actual perim-
eter, and the resulting ratio used to eliminate
land cover polygons of irregular shape. Results
were verified using aerial photography of the
region.

As shown in Figure 68, there is a scattering of
possible  areas where estimation of evapotrans-
piration may be made using the point methods
discussed.  The total available area covers only
18% of the  8-county footprint. Of this 18%,
the major land type cover is cultivated crops
(74%) with the greatest coverage in Crittenden
County, Arkansas, Tunica County, Mississippi
and Tipton County, Tennessee. The presence
of this land  cover type in these areas (see

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                                   90 0-0-W
                                                                    89-0'0-W
       0  5  10     20 Miles                    QD
                                          Land Cover Type
                                             in land (RocWSancltlay i [" 10
                                          I I (.'u'l .• j-t J . i <. k-,     [  ] DC .eloped Medium i"tgn*4y ^| V 'c d *c re •,'     ^| V'A = r,- *ct a"<

Figure 67.   /_anof cover fypes present within the study area at 200 meter resolution (from MRLC consortium

            2001 Land Cover Database).
Figure 67) is understandable based on the
amount of rice, cotton and soy agriculture in
these counties.  Forested areas (< 5%), exclud-
ing wetland habitat, was unexpectedly small;
however, wetland areas were large (17%)
with coverage primarily along the Wolf River
in Tennessee, Coldwater River in Mississippi
and along the Mississippi River.  Not shown
in  Figure 68 but illustrated in Figure 64 is the
developed area of Memphis, Tennessee in
Shelby County.  Though the high, medium
and low developed land cover areas could be
lumped into a single "developed" land cover
classification, it is unknown if the heterogeneity
of  the developed areas can be accurately rep-
resented using a point measurement method.
Certainly combining point measurement data
with remote sensed data will offer the greatest
means at estimating evapotranspiration con-
tiguously over the MERGWS footprint.
Concluding remarks
There are multiple methods that can be used
to estimate evapotranspiration within the study
area.  Two remote sensing applications and
three point measurements methodologies
have been proposed. The three point-based
measurements (weather station, Bowen ratio
towers, and eddy covariance towers) differ in
the type of instrumentation being deployed,
the number of assumptions, the cost, and
the equations being employed. Each point
measurement  method requires similar, if not
identical, local site conditions that enhance
sampling accuracy of the evapotranspiration
measurement. Those conditions include, fetch,
uniform land cover distribution (similar growth
height), measurement or estimation of heat
flux, uniform slope, and limited microclimate
variation. Each of these point measurement/
estimation methods is reasonably accurate
and locally representative of a similar area of

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                                     90'0'0-W
0   b  10
                                                 Legend
                                                   Defined study area
                                                 Land Cover Type
                                                 H Barren Land (FtoeWSand/Clay >
                                                   CultwaWb Crops
                                                      Deciduous (ixesl      Shrub/Scrub

                                                     | Developed Open Space H Woody Wetlands
Figure 68.   Depiction of contiguous areas of similar land cover type for possible implementation ofevapo-
            transpiration point measurement instrumentation.
coverage based upon wind speed and tower
height. All three methods can be deployed for
extended measurement at remote locations.

Bowen ratio and Eddy Covariance methods
are most suitable for extended, unmaintained
sampling as fewer assumptions are required
and local recalculations are not as necessary
as with the standard weather station derived
Penman-Monteith (Dugas et al., 1998). The
Eddy covariance stations are the most accu-
rate, site specific deployable systems which
rely upon the fewest number of assumptions,
directly measuring the heat flux.  Given the
available options, the recommendation is to
deploy eddy covariance stations alongside
basic weather stations calculating evapotrans-
piration using the Penman-Monteith equation.
This setup will provide initial robustness of the
calculation and the weather stations can be
calibrated alongside the eddy covariance sta-
tions, potentially allowing the eddy covariance
stations to be moved to new sample locations
                                      while the weather station continues to sample
                                      and record evapotranspiration at the original
                                      site. Additionally, it is recommended that these
                                      point measurements be run on identical land
                                      cover types to determine if the measurements
                                      at similar land cover types are representa-
                                      tive and  can be applied to the remaining land
                                      covers of similar type within the study area,
                                      thereby,  reducing deployment cost and time.

                                      Remote  sensing data allows for evapotrans-
                                      piration estimation over a broader region than
                                      the site measurements. Currently the only
                                      scientifically accepted method is to utilize
                                      the MODIS datasets with the 1 km resolu-
                                      tion.  Unfortunately the MODIS data does not
                                      allow for local station correction as the data
                                      is provided only as a raster output. However,
                                      the measurements from the eddy covari-
                                      ance towers could be provided to NASA to
                                      be incorporated within the evapotranspiration
                                      calculation from the raw MODIS  data (Mu, Q.,
                                      personal communication, 2007).  Processing

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Landsat data will not net true evapotranspira-
tion rates, yet only indicate where higher
variability may exist  within the study area. The
rGlS-et tool is primarily designed for two crop
types, neither of which is used within the study
area.  This puts limitations on  how and where
this method can be employed; thus, it seems ill-
suited for use within the MERGWS study area.

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                                                                                     6.0
                                       Summary and Recommendations
The purpose of this study was to investigate,
document, and build a comprehensive data-
base to assess long-term sustainability of the
quantity and quality of ground-water resources
in the tri-state area of Tennessee, Mississippi
and Arkansas, Demand for ground water
by agriculture, municipalities and industry is
presently stressing the sustainable yield of the
aquifers.  The stresses on the aquifer systems
have led to localized ground-water contamina-
tion which in certain instances have closed
water-treatment facilities (e.g., Parks, 1990;
Bradley, 1991; Parks and Mirecki, 1992; Gentry
et al., 2006), declines  in the potentiometric
surfaces of unconfined and confined aquifers
(Parks, 1990; Kingsbury, 1996; Fitzpatrick et
a!., 1990; Hays and Fugitt, 1999; Arthur, 2001)
and localized declines in water quality (Parks
et al., 1995; Larsen et al., 2003; Gentry et al.,
2005; Schrader, 2001). These problems have
the potential to threaten  human health as well
as impede economic development in the region.
This study is the first phase of a four-phase
research effort to understand, model, and
suggest best management practices for the
ground-water resources  in the tri-state area of
Tennessee, Mississippi, and Arkansas.

The objective of Phase I is to develop the
intellectual, organizational, and methodological
foundation for the subsequent three phases.
Phase I specifically addresses EPA's mission of
protecting human health and the environment
by (1) conducting an assessment of data stores
existing at the state and  local level, (2) evaluat-
ing data needs at the regional scale that will
sharpen our understanding of the regional
ground-water system and its connection to
other environmental processes, and (3) orga-
nizing data collection practices on a regional
scale that will assist with addressing ground-
water resources in a holistic manner. The work
plan for Phase I was subdivided into five main
topics: (1) perform geologic mapping of the
region; (2) ascertain water quality changes and
ground-water contamination threats; (3) con-
duct assessment on aquifer parameter values
and measurement methodologies; (4)  catalog
surface water sources to ground water; and
(5) diagnose additional sources/sinks  of water
to the ground-water system.

Regarding the geology of the region, the
various geologic units of interest (Tertiary and
younger) are referred to by many names. This
variability in naming convention only scratched
the surface of the underlying issue which
was the discontinuity  in mapping these units
at a regional scale with unit delineation often
terminating at state boundaries.  Additionally,
little work had been done prior on identifying
and mapping interbedded units of significance,
again within a regional framework. Through
this investigation, a number of high-quality geo-
physical logs were analyzed and unit boundar-
ies identified and mapped, this resulting in
reducing but not eliminating the aforementioned
deficiencies.  Further work is still needed to
address gaps in our understanding of  the
geologic framework that will include drilling
exploratory boreholes (that can be converted to
observation wells) and geophysical mapping.

Water quality data availability varied by state
and was often greatest within the aquifer of
primary use.  In Eastern Arkansas and northern
Mississippi, water quality data was greatest in
the Quaternary Alluvial aquifer. In Tennessee,
it was the Middle to Lower Claiborne aquifer.
Still, an attempt was made to assess water
quality changes over  time across the aquifers
of interest.  Water quality in the Quaternary
Alluvial aquifer is suitable for municipal use, yet
is widely used for irrigation. Water chemistry in
this system is strongly correlated to recharge
sources, but also suggests infiltration of waters
at depth through faulting.  Water usage from the
Upper Claiborne aquifer within the study area
is limited mostly to West Tennessee, primarily
withdrawn for irrigation. With the limited data in

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the study area, definite associations between
water quality and possible sources cannot be
easily drawn. Contrary to data availability in
the Upper Claiborne, a large amount of water
quality data  exists for the Middle Claiborne
aquifer. This system is relied upon heavily by
municipalities and industry because  of its high
quality.  Changes in water chemistry are due to
recharging water in  the unconfined areas (outer
aquifer margins)  and localized upwelling of
deeper water as  well as water exchange from
upper aquifers. The Lower Claiborne - Wilcox
aquifer is also of high quality, yet is subject to
deeper water intrusion, thus increasing salinity
in place, especially south toward the Gulf of
Mexico. Relationships amongst water sources
and processes affecting water quality are most
clear in the Quaternary Alluvial and Upper
Claiborne aquifers, and less so in the Middle
and Lower Claiborne-Wilcox aquifers. This
seems likely due to  the lumped classification of
these aquifer units.  More detailed analysis of
the water quality trends and factors in the lower
Tertiary aquifers  will require further subdivision
of the aquifers and regional consistency in
application.

A hidden or  out-of-sight impact to water quality
is a reduction in  the integrity of aquitards to
prohibit ready exchange of vertically adjacent
ground waters. Often called breaches or win-
dows, the presence of these features, whether
geomorphic  or tectonic in origin, have resulted
in the exchange  of younger more contaminant
prone ground water to leak into deeper, more
pristine ground water reservoirs.  Though these
breaches are local in scale, the capacity for
ground water exchange through them can have
a regional and possibly costly impact on water
quality.  Understanding the originating pro-
cesses that  formed  these breaches and their
extent and characteristics should be a major
driver for future investigation, especially since
many of the  breaches identified  occur in heavy
urban areas.

Critical components that should be well under-
stood and quantified to address the long-term
sustainability of the  quantity and quality of
ground-water resources in the tri-state area
are the inputs and outputs to the ground-water
system and  the characteristics of the geology
through which the water flows. Regarding the
latter, no comprehensive effort has been per-
formed to regionally assess aquifer parameters
such as hydraulic conductivity and storativity
- porosity can also be added to this list though
not analyzed in this study, yet is important
for contaminant transport.  Additionally, the
hydraulic conductivity of aquitards is also
important.  Greater aquifer parameter data exist
than that for aquitards; however, a data confi-
dence analysis on the available data suggests
that only 23 of 122 aquifer tests are reliable;
these 23 tests all within  Shelby County for the
Lower Claiborne and Upper Wilcox aquifers.
A concerted effort to quantify aquifer/aquitard
parameters over the seven-county study area
and bordering counties should be included in
any future work. As part of this recommenda-
tion, assessment of parameters for the Lower
Claiborne aquifer over its larger thickness
should be considered as the interbedding of
significant clay units within this aquifer may
compartmentalize flow and thus result in a
possible differentiation of water quality within
the aquifer.

Surface water sources to the ground water
system  include rivers and wetlands. There
are five major river systems in the study  area
- the largest of which is the Mississippi River;
however, the four investigated as part of this
study are tributaries to the Mississippi  River. Of
these four tributaries, three were investigated
for riverbed hydraulic conductivity, yet all four
and some of their tributaries were analyzed for
baseflow conditions.  Results from the con-
ductivity assessment indicated that USCS soil
classification did not provide reliable results as
conductivity values could vary as much as five
orders of magnitude. Determination of riverbed
conductance by empirical means did provide a
smaller range of values; however, the number
of grain size analyses available for analysis
is very limited. Obtaining good estimates of
riverbed conductance is necessary to properly
model ground water/surface  water interaction.
To this end, it is recommended that in  situ
determination of riverbed conductance through
additional grain size analyses (none of those
available were actually taken from the  river
channel) or from falling head permeameters be
deployed within the stream channel.

-------
Baseflow conditions for 17 gages within the
study area were assessed.  Period of record
for the gages range from 1 to 11 years with
the average period of record around  5 years.
Unfortunately, the number of river gages is
limited, discontinued over time either because
the project for which the gage was installed
ended or they were simply discontinued due to
budgetary constraints. The greatest  number of
gages exists on the Wolf River and its tributar-
ies. A comparison of baseflow conditions along
the Wolf River shows a change in baseflow
between the period of 1951-1962 and more
recently 1997-2005. This change is attributed
to land use change of the area; however, this
assessment is complicated by the fact that the
Wolf River was dredged and channelized in the
early  1960's. The remaining river systems have
either a single gage or the period of record for
multiple gages on the  same river system do not
correlate; hence, few conclusions can be drawn.
Should river gages be reinstituted at a greater
density in Phase II of this effort?  We recognize
that gaging will be required to provide closure
to the water balance budget, but whether or
not permanent gages are needed has yet to be
determined.  Accessibility and safety are two
important factors that should play a role in this
decision.

For this investigation, wetland data was com-
piled for the seven-county study region.  No
assessment was planned for determining the
impact of the wetlands to ground water quantity
and quality. Wetland information was obtained
in CIS format from the US Fish and Wildlife
(FWS) National Wetland Inventory (NWI)
program. Wetland coverage for the four study
area counties in Tennessee is complete, yet
dated. Mississippi has partial coverage (-50%)
in two of the three investigated counties while
Crittenden County, Arkansas has less than
10% coverage. Wetlands are expected to have
an interactive role with the local ground-water
and other surface water systems; however,
specifically what that connection and their
importance are will need to be determined
during Phases II and 111.

Two additional processes that will play a
critical role in assessing the sustainable
yield and quality of ground water in the
region are evapotranspiration and recharge.
Evapotranspiration will be important for clos-
ing the water balance, especially in Arkansas
and Mississippi where flooding of rice fields
is most predominant. A variety of techniques
are available for estimating evapotranspiration
that range in price and accuracy; however,
determination of the most appropriate method
will depend on site scale and its characteris-
tics.  Where smaller, mobile evapotranspiration
towers may be used more extensively; we
recommend that at least three Eddie covariant
towers be installed in dominant landscapes that
represent agriculture, urban and forest environ-
ments. Though these towers are expensive,
there could be cost savings with installation/
maintenance should these towers be incor-
porated into the national evapotranspiration
ground-truth network.  Modeling evapotranspi-
ration on a regional scale can be accomplished
by using the ground towers to validate and
correct MODIS satellite measurements. Soils
data acquired and compiled from the NRCS as
part of this project as well as land cover data
through the MRLC can supplement evapotrans-
piration measurements. They can also be used
to supplement recharge estimation.

Recharge is a critical component to the hydro-
logic cycle, one that has been generalized, via
numerical ground water models, or simply over-
looked in the region  until recently.  Estimation
of recharge will include a suite of tools and
methods  that could include the water balance
approach, quantifying river baseflow, mapping
vadose zone and ground water tracers, or
employing physical measurement using iysim-
eters, soil moisture probes, neutron density
probes, or correlating temperature changes
along fiber optic cable to water migration. We
anticipate recharge to be the driver of water
supply to a regional  ground water numerical
model. This suite  of tools to estimate recharge
will result in  a range of rates that, depending
on the tools used, could be linked to  land use
and thus  provide a heterogeneous distribution
of recharge rates across the region. This range
of recharge rates can also be used to bound
parameter estimation schemes often applied to
ground water models.

-------
This phase of the Mississippi Embayment
Regional Ground Water Study was to compile
the enormity of hydrogeoiogic data available.
Much of this data existed in a variety of formats
with varying quality,  A valiant attempt was
made to unify these dataset so comparisons
at a regional, multi-state scale could be per-
formed. Just as ground water knows no politi-
cal  boundaries, so must the data describing the
ground water system also follow this principle.
With this reconnaissance phase complete,
Phase II of the effort can build from the foun-
dation developed herein and  we can proceed
forward with improving our understanding of
this important regional ground-water system.

-------
                                                                                             7.0
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-------
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                    8.0
Appendix Geophysical Logs

-------

-------
     G

    SW
Ml 08090596001
Plate 1: Section  G-GJ
                                                     342657090391901
                                                                                                                                                     350520090180701    1

                                                                                                                                                                350955090173601
                                                                                                                                                                                 351722090153601

                                                                                                                                                                               ^—l—I—:—I—i-
                                                                                                                         9
                                                                                                                  353344090021002

                                                                                                           1—I—i—H-H
        10
 353912089562601
—i—M—i—i—f-
                                                                                                                                                                                             aaŦŦ^Ŧŧ...c =|=|= = =  =
                                                                                                                                                                                             Wi.-u-—~u	
                                                                                                                                                                                                  _L        _M
                                                                                                                                                                                                     i             ii

                                                                                                                                                                                                             Scale
                                                                                                                                                                                                        tertica! exaggeration - 100 1

                                                                                                                                                                            Upper and lower contact
                                                                                                                                                                            of upper Memphis Sand
                                                                                                                                                                            and equivalents
                                                                                                                                                                            Internal clay-nch intervals
                                                                                                                                                                            m Middle Memphis Sand
                                                                                                                                                                            and equivalent
                                                                                                                                                                            Upper and lower contact
                                                                                                                                                                            of lower Memphis Sand
                                                                                                                                                                            and equivalents
                                                                                                                                                                            Other formalional contacts
                                                                                                                                                                            Inferred or questionable contact

                                                                                                                                                                       - -  Intra-fomiakona! contact
                                                                                                km
                                                                                                 4
                                                                                                        8
                                                                                         Faults and colors

                                                                                        Inferred from this study
                                                                                         airts based on Csontos (2007)

-------
                                              Plate 1: Section G-G'
Ld:F-004
     12
3S4859089562601
  13
troy_#2
   G'

   NE

  14
Ob:O-004

-------
  A
 NW

  1
                                                                                                              Plate  2:  Section A-A
355403090340201
LSE 270
                         355314090010801 355607090152601
                         LSE 232         LSE 236
                                                                                                                                         jackson_utilities_#1
                                                                                                                                         LSE 32 3
  Correlation lines

         Land surface

         Base of Quaternary
         section
         Internal clay-rich intervals
         in Middle Memphis Sand
         and equivalents
         Upper and lower contact
         of Memphis Sand
         and equivalents
       •  Otherformational contacts
~~ ——   Inferred or questionable contact

 - - -   Intra-formational contact
*
                                                                                                                                                                 Scale
                                                                                                                                                           \ertical exaggeration -100:1
                                                                                                                                                                    km
                                                                                                                                                            02468


                                                                                                                                                            Faults and colors
                                                                                                                                                            .        	"	
                                                                                                                                                          Inferred from this study



                                                                                                                                                          Faults based on Csontos (2007)

-------
                                                                                                                                 ,>,.
         Internal clay-rich intervals
         in Middle Memphis Sand
         and equivalents
         Upper and lower contact
         of Memphis Sand
         and equivalents
       1 Other formational contacts
         Inferred or questionable contact

~ - -    Intra-formational contact
*
 .1
  Faults and colors

Inferred Irom triis study



Faults based on Csortos (2007)

-------
Plate 4:  Section  C-C1
  Upper and lower contact
.  of upper Memphis SaiKl
  and equivalents
  Internal clay-rich intervals
.  In Middle Memphis Sand
  and equivalents
  Upper and tower contact
  of lower Memphis Sand
  and equivalents
• Other fonmational contacts

  Inferred or questionable contact

  Intra-formational contact
                                             Inferred from this study
                                           F Faults based on Csontos (2007)

-------
   3

ŧ22020903Ŧ2701
                       J5161M302JJ701   H1245WI>224S013MM70S01MŦ1
                                      ar        arr  J50S2MM1!0701
                                                       ŧ?;
                                                         ,
                                                    Plate 5: Section  D-D1
AR  ;| TN

 8

AR H2


                                                                                                             FaJŦ bawxl 01 CscnŧM2W!

-------
Plate 6:  Section  E-E1
                                                                                                            17    18
                                                                                                                              E'

                                                                                                                              SE


                                                                                                                              19
        Correlation lines

               Land surface
                                             Scale
                                       Xfertical exaggeration -100:1
        Internal clay-rich intervals
        in Middle Memphis Sand
        and equivalents
        Upper and lower contact
        of Memphis Sand
        and equivalents
      • Other fomialional contacts
•  —   Inferred or questionable contact

* - -   Infra-format tonal contact

                                                Faults and colors

                                               Inferred from this study
                                              Faults based on Csonlos (2007)

-------
  NW
    1         2      3
                                Plate  7: Section F-F'
                                                                                                                                                                                                                                                     SE
                                                                                                                                             13      14      15  16
                                                                                                                                MS "AN LOOM MSPAM Ŧ)096  V3       V0058  MS^WN VUOGU
                                                                                                                                          LSi.3-0      LSt286    LSt 360 LSL 330
                   34SS38U3-IJ-UW
                   LSE210
                                                                 WS3109045580.     3U223090412I01
                                                                 LSi. 225           "-55; 210
LSt 210      34581409102420-
           LS_ ill'i
   MCW. MS*N. LŦH     K-MH
LSEU7  LSE25S        LSt IB!
                                                                                                                       Scale
                                                                                                                \6rticai exaggeration -100:1
                                                                                                                          km
                                                                                                                  02468
Base of Quaternary
section
                                                                              Internal clay-rich intervals
                                                                              in Middle Memphis Sand
                                                                              and equivalents
                                                                              Upper and lower contact
                                                                              of Memphis Sand
                                                                              and equivalents
                                                                             Other formational contacts
                                                                        —   Inferred or questionable contacl
                                    Faults and colors
                                  Inferred from this study
                                  Faults based on Csontos (2007)
                                                                              Intra-formational contact

-------
    A
of

-------
Appendix B

Well Log Ranking Chart
Well logs were ranked according to log type,
location and elevation accuracy. Log type rank-
ing was determined using the decision matrix
below (Table App1).  Only logs that had a rank
of >6 were used in this report and are provided
here in the Appendix.

Table App1.   Data ranking system for geophysical
              log data.
Log type
Geophysical - Gamma
Resistivity
Density
Spontaneous potential
Geologist
Drillers
Seismic
Geophysical log quality
Readability
Clear text
Fuzzy text
Signal strength
Strong: fades changes noticeable
Weak: minimal changes in signal over
length of log
Consistency
Many groupings of logs drilled by same
driller over short time period
Individualized drilling
Rank
5a
4(+1)a
+1
+1
4
2
7


+1
0

+1
0

+1
0
Well location ranks were determined by the
decision matrix illustrated in Table App2.

Table App2.   Numerical ranking system for spatial
              location data (x,y).
' Base ranking with additive ranking possible inclusive of other
     logs
Location
method
GPS
Survey
Approximation
using a refer-
ence map
Graticule
grid
Georeference
Approximation
using a refer-
ence grid
TRS
Scaling
Geocoding
N/A
Rank
8
10

6
7

5
3
4
1
Accuracy
DMS
no digits after the decimal
Second
1 digit after the decimal
Second
2 or more digits after the
decimal Second
DD
4 or less significant digits
5 to 6 significant digits
7 or more significant digits
UTM
Stateplane


USGS 1:24000 or smaller
scale
USGS or peer reviewed
publication (figure)
Other publication


Section
quarter section
quarter-quarter section
quarter-quarter-quarter or
more section



Addi-
tive to
Rank

+0
+1
+2

+0
+1
+2
+2
+2


+2
+1
+0
___

+0
+1
+2
+3


—
                                                  Lastly, the elevation rank was determined using
                                                  the ranking  matrix shown in Table App3.

                                                  Table App3.   Ranking system for elevation
                                                                data  (z).
Point elevations
GPS
Differential GPS
Survey GPS
Barometer-GPS
Survey
Approximation
Rank
Low
Medium
High
Medium
High
Low

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Table App4.    Rankings of well logs including that for assessing the log, location and elevation.
Well ID
P-011
O-011
H-007
H-002
H1
F5
D-001
A-001
S1
P3
P1
D-003
D5
C-001
A-002
Withers-001
B-009
M1
L4
A1
A5
E1
E2
K2
G4
M-002
M1
K2
K1
H-001
G-012
G-7
G-6
G-5
G-3
G-1
F-2
F-1
E-3
E-1
A-001
Longitude
-89.098611
-89.186550
-89.242361
-89.235950
-89.181281
-89.073700
-89.335833
-89.635525
-89.463328
-89.555244
-89.369031
-89.684717
-89.687067
-89.410103
-89.626664
-90.201217
-90.037778
-89.822533
-89.954286
-90.108453
-90.154317
-90.243922
-90.207100
-90.071275
-89.968275
-89.932733
-89.937547
-90.179339
-90.179650
-89.837481
-89.958533
-89.966239
-89.973192
-89.956600
-89.957267
-89.968047
-89.990597
-90.081244
-90.182206
-90.189292
-90.101847
Latitude
34.654722
34.618022
34.825961
34.801131
34.847500
34.894061
34.921111
34.977311
34.663781
34.766586
34.691669
34.865525
34.870772
34.947600
34.971917
34.904947
34.994722
34.831256
34.772264
34.963333
34.953478
34.890117
34.903408
34.734253
34.633056
34.566578
34.571442
34.572483
34.572056
34.604561
34.597731
34.631703
34.613714
34.620919
34.620919
34.632253
34.612178
34.618983
34.656619
34.662283
34.718042
Elevation
(ft)
580
420
520
513
613
620
615
400
400
513
500
338
360
475
420
210
290
260
360
305
210
200
207
243
250
320
320
320
320
370
305
250
300
268
260
250
340
340
210
280
275
State
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
County
Benton
Benton
Benton
Benton
Benton
Benton
Benton
Marshall
Marshall
Marshall
Marshall
Marshall
Marshall
Marshall
Marshall
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Tate
Total
Depth
537
552
916
525
930
1551
1364
694
1294
1313
681
1715
1737
737
1770
3800?
1521
646
1438
1668
1614
2004
1290
1589
1268
1103
1115
1668
1517
1170
1212
1192
1285
1197
1217
827
1242
1518
1627
1799
600
Log
Rank
8
7
9
9
6
6
9
9
6
5
7
5
6
9
8
7
9
6
6
7
7
7
7
7
7
9
7
8
8
6
9
7
8
7
7
7
6
6
8
8
7
Location
Rank
14
8
8
8
7
8
14
8
7
8
8
6
8
8
5
5
8
8
8
8
8
8
7
7
8
8
8
8
8
8
8
7
8
6
6
8
8
7
8
8
8
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
M3
R2
S-1
S-003
V2
V3
V-0058
W-1
W-004
K-002
K-5
H-5
H1
G-009
G6
Danner #1
Sanderson #1
Leach #1
HaK-012
HaG-12
Q-3
K-28
F-1
G-12
J-5
N-3
N-8
N-9
R-3
S-3
U-1
O-10
H-21
H-17
F-9
H-6
H-20
U-18
R-45
R-43
R-47
Longitude
-89.930000
-90.070000
-89.790000
-89.870000
-89.940000
-89.940000
-89.902072
-89.811217
-89.849239
-90.097406
-90.182994
-89.847819
-89.824503
-89.926500
-89.912694
-90.153681
-90.346003
-90.370350
-89.380833
0.000000
-88.800278
-89.005000
-89.017500
-89.645278
-89.454722
-89.538889
-89.607222
-89.544444
-89.636111
-89.535000
-89.366667
-89.390833
-89.528889
-89.525556
-89.825833
-89.528333
-89.537222
-89.978611
-89.731389
-89.720833
-89.710278
Latitude
34.490000
34.320000
34.290000
34.340000
34.220000
34.240000
34.194778
34.166825
34.164739
34.394111
34.393886
34.436256
34.467100
34.441631
34.448089
35.316008
35.133594
35.256622
35.660000
0.000000
35.303333
35.138611
35.031667
35.699444
35.732500
35.804444
35.794444
35.795556
35.894444
35.885000
35.883056
35.821667
35.745556
35.660278
35.644167
35.745556
35.632222
35.266667
35.146389
35.149167
35.131111
Elevation
(ft)
320
210
440
250
279
285
350
330
330
182
165
360
420
350
340
225
207
215
340
343
510
570
630
360
469
491
342
387
258
279
273
308
430
325
437
420
305
246
340
340
294
State
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
AR
AR
AR
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
County
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Crittenden
Crittenden
Crittenden
Hay wood
Haywood
Hardeman
Hardeman
Hardeman
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Lauderdale
Shelby
Shelby
Shelby
Shelby
Total
Depth
1154
805
928
555
986
1185
581
625
1025
904
1712
993
1104
1415
1152
3351
3504
3454
1102
357
359
760
819
427
452
583
333
406
252
465
408
416
111,
297
352
755
443
475
693
1313
1319
Log
Rank
7
7
7
9
7
7
9
7
6
7
7
7
7
9
7
0
7
7
7
7
7
6
9
10
10
10
10
10
10
9
7
10
7
10
8
7
3
7
9
9
9
Location
Rank
8
8
8
8
8
8
8
8
8
8
8
8
8
6
8
0
5
5
8
2
6
6
6
6
6
6
6
6
6
6
8
6
6
6
6
6
6
6
6
6
6
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
P-69
P-205
J-32
Q-62
R-23
R-21
U-30
U-48
L-17
P-142
P-207
K-45
O-143
O-112
Q-3
P-79
P-75
O-113
C-81355
Corehole #1
IE-81357-AL
21-9S-8W
Corehole #5
Corehole #6
Corehole #7
28-29N-2W
IL-90319
Johnson #1
20-5S-6W
IL-87490
ud-#5
greystone#1
greystone#2
ardie_rd_th_#1
power_#1
dist_pkwy_th_#1
flem_rd_th_#1
flem_rd_th_#2_pie
syc_rd_#1
fleischmanj 2_05
hunt wesson
th_#1_wel!8
Longitude
-89.923146
-89.950000
-90.073984
-89.858333
-89.731944
-89.727222
-89.972313
-89.957500
-89.858421
-89.961389
-89.952222
-89.933705
-90.019257
-90.022590
-89.751195
-89.942589
-89.923699
-90.022868
-89.903083
-89.880731
-89.928444
-90.044869
-89.985794
-90.188889
-90.039922
-90.405025
-90.460758
-89.542292
-89.864042
-90.417875
-89.714680
-89.392110
-89.392110
-89.835700
-89.209764
-89.669181
-89.705990
-89.707000
-89.671800
-90.085017
-90.017964
Latitude
35.205644
35.246667
35.115924
35.190556
35.146667
35.153611
35.268698
35.353889
35.122589
35.242222
35.236944
35.116201
35.153423
35.174256
35.160645
35.127034
35.212866
35.174256
34.291583
34.541542
34.226256
34.292047
34.469314
34.477583
34.279056
34.356042
34.168092
34.610228
34.633875
34.518164
35.556470
35.652450
35.652460
35.255747
35.541828
35.033842
35.024920
35.024000
35.036044
35.076733
35.121755
Elevation
(ft)
318
258
281
307
340
305
245
267
310
301
246
289
250
245
320
302
330
245
360
328
244
205
338
177
219
166
163
385
282
213
387
318
318
290
340
370
345
335
360
240
308
State
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
County
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Panola
Panola
Panola
Panola
Panola
Panola
Panola
Coahoma
Panola
Marshall
Tate
Tunica
Tipton
Haywood
Haywood
Shelby
Haywood
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Total
Depth
346
1548
422
890
758
1185
496
312
223
850
1569
1360
383
483
481
374
305
473
3263
3014
4959
2457
3710
3530
3312
11495
17600
4003
2880
11930
678
839
834
825
441
401
537
511
414
635
528
Log
Rank
9
9
7
7
9
9
7
7
7
9
7
7
7
7
7
7
7
7
7
7
8
7
7
7
7
9
7
7
7
7
9
10
10
9
8
9
9
9
9
9
9
Location
Rank
2
6
2
6
6
6
1
6
2
6
6
2
2
2
2
2
2
2
5
5
5
5
5
6
6
6
6
5
5
5
10
10
10
1
1
1
10
1
1
10
1
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
ld_co_wa_#6
mason_11_03
hw_floor_th1_well2
milan_piez_#1
milan_piez_#3
milan_piez_#4
milan_piez_#5
milan_th#1
paris_2_04
vertex_th1
allegheny_
energy_#1
allegheny_
energy_#2
american_
yeast_#1
bartlett ardie
rd_963ft
bartlett gtown
th#1
birmingham
steel_th#1
birmingham
steel_th#2
buckeye#1 8
calpine_#7
calpine_th_#1
dyersburg fabric
th#1
haywood_
energy_#3
Jackson utili-
ties_th#1
mapco_th#1
munford_571ft
troy_#1
troy_#2
dyersburg #10
th_#3_911ft
dyersburg #10
th_#3_1 075f
dyersburg #11
th#1
dyersburg #12
th#1
AR035_000001
AR035_000002
Longitude
-89.531760
-89.534640
-90.035389
-88.771430
-88.770820
-88.769710
-88.773050
-88.771090
-88.327333
-90.140000
-88.619920
-88.620820
-90.054730
-89.836736
-89.792425
-90.151620
-90.153820
-89.993650
-89.378910
-89.381000
-89.370430
-89.425000
-88.812920
-90.082310
-89.809760
-89.161440
-89.161389
-89.368200
-89.368200
-89.367590
-89.367480
-90.29399
-90.21676
Latitude
35.807310
35.411790
35.185275
35.921190
35.921190
35.921220
35.921260
35.921190
36.301567
35.083889
36.222050
36.221540
35.191060
35.254636
35.212097
35.055830
35.055870
35.171530
35.658960
35.661000
36.036490
35.422800
35.604460
35.085050
35.447770
36.339810
36.339444
36.036810
36.036810
36.034360
36.034600
35.16620
35.06232
Elevation
(ft)
431
310
240
466
460
454
487
463
530
249
421
410
250
287
327
210
210
240
323
334
334
377
373
231
448
361
357
325
325
308
307
211
210
State
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
AR
AR
County
Lauderdale
Tipton
Shelby
Gibson
Gibson
Gibson
Gibson
Gibson
Henry
Shelby
Weakley
Weakley
Shelby
Shelby
Shelby
Shelby
Shelby
Shelby
Haywood
Haywood
Dyer
Haywood
Madison
Shelby
Tipton
Obion
Obion
Dyer
Dyer
Dyer
Dyer
Crittenden
Crittenden
Total
Depth
613
289
506
377
360
361
386
379
414
471
304
320
704
972
818
607
721
620
1181
1292
789
1197
431
547
692
1403
1417
908
1066
912
932
295
295
Log
Rank
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
10
10
9
9
9
9
9
9
9
9
10
10
8
10
10
10
10
10
Location
Rank
10
1
1
1
1
1
1
1
10
1
1
1
1
1
1
1
1
1
10
9
1
1
1
1
10
1
8
1
1
1
1
8
8
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
High
High

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
AR035_000003
AR035_000004
AR035_000005
MSA006
MSA007
MSB005
MSB008
MSB0074
MSC004
MSD008
MSD009
MSF2
MSF0113
MSG009
MSJ002
MSL005
MS033_000001
MS033_000003
MS033_000004
MS033_000007
MS033_000008
MS033_000014
MS033_000024
MS033_000032
MS033_000033
MS033_000034
MS033_000044
MS033_000050
MS033_000051
MS033_000053
MS033_000054
MS033_000057
MS033_000064
MS033_000066
MS033_000074
MS033_000079
MS137_000037
MS137_000039
MS137_000040
MS137_000041
MS137_000042
Longitude
-90.22982
-90.10787
-90.29399
-90.10861
-90.10861
-89.99778
-90.04139
-90.04000
-89.92917
-89.77722
-89.86222
-90.03194
-90.01611
-89.99778
-90.15278
-89.94444
-89.93454
-89.89972
-89.90754
-89.97105
-89.93772
-89.97559
-89.89975
-89.92652
-89.89733
-89.96812
-89.96393
-89.95020
-89.93395
-89.90442
-89.92212
-89.88078
-89.96020
-89.81980
-89.95342
-89.79481
-89.97986
-89.97121
-89.96684
-89.95329
-89.94875
Latitude
35.12343
35.23037
35.16620
34.96333
34.96333
34.96750
34.98139
34.99472
34.95000
34.96778
34.97222
34.94361
34.87056
34.91750
34.83000
34.81417
34.83139
34.79732
34.82936
34.82782
34.86096
34.79593
34.86958
34.91848
34.94501
34.91204
34.77358
34.93515
34.89674
34.91821
34.94733
34.98957
34.85969
34.97096
34.97148
34.98426
34.55561
34.56628
34.58083
34.58107
34.57036
Elevation
(ft)
212
217
205
302
308
320
281
275
390
392
395
340
275
350
310
390
298
244
320
340
347
382
301
380
360
340
360
385
385
360
395
350
330
412
380
400
335
305
318
270
270
State
AR
AR
AR
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
County
Crittenden
Crittenden
Crittenden
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
DeSoto
Panola
Tate
Tate
Tate
Tate
Total
Depth
295
295
295
545
1638
499
1015
1554
443
500
570
1650
1525
497
1609
405
296
297
297
297
287
296
295
297
296
296
214
276
297
296
297
297
296
418
373
458
297
297
297
297
297
Log
Rank
10
10
7
9
9
9
9
9
9
9
9
6
9
9
9
9
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
4
3
4
10
10
9
10
10
Location
Rank
8
8
8
14
14
14
14
12
14
14
14
13
16
8
14
14
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
8
7
7
7
7
7
7
Elevation
Rank
High
High
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
MS137_000047
MS137_000048
MS137_000049
MS137_000160
MS137_000163
MS137_000164
MS137_000165
MS137_000173
MS137_000184
MS137_000186
MS137_000187
MS137_000194
MS137_000195
TN047_000007
TN047_000009
TN047_000021
TN047_000022
TN047_000023
TN047_000024
TN047_000025
TN047_000072
TN047_000074
TN047_000075
TN047_000076
TN047_000079
TN047_000084
TN047_000096
TN047_000097
TN047_000098
TN047_000099
TN047_000125
TN157_000025
TN157_000026
TN157_000027
TN157_000034
TN157_000035
TN157_000039
TN157_000044
TN157_000046
TN157_000047
TN157_000085
Longitude
-89.93575
-89.91828
-89.89579
-89.95886
-89.93573
-89.91822
-89.90064
-89.89639
-89.90095
-89.93599
-89.94415
-89.97179
-89.95821
-89.60340
-89.62420
-89.59341
-89.53063
-89.55657
-89.55778
-89.51272
-89.39422
-89.46487
-89.49398
-89.36118
-89.37618
-89.31719
-89.34315
-89.30729
-89.29310
-89.26024
-89.42246
-90.00561
-90.05398
-90.02695
-90.03454
-89.99996
-90.00844
-90.01323
-90.02431
-90.00620
-89.89592
Latitude
34.56612
34.57027
34.57024
34.69418
34.55571
34.55561
34.55906
34.64328
34.67590
34.64686
34.66858
34.68304
34.66162
35.11488
35.15328
35.17209
35.11101
35.11876
35.15762
35.17202
35.16061
35.17658
35.11828
35.17886
35.12964
35.15962
35.11587
35.11426
35.17623
35.17493
35.16623
35.15558
35.14620
35.15438
35.13481
35.15671
35.15442
35.15322
35.15414
35.13565
35.11454
Elevation
(ft)
320
265
310
315
342
360
261
310
361
323
340
270
322
433
402
369
385
342
371
408
502
415
430
479
462
468
471
388
527
559
454
252
268
255
272
251
250
249
259
280
315
State
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
MS
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
County
Tate
Tate
Tate
Tate
Panola
Panola
Panola
Tate
Tate
Tate
Tate
Tate
Tate
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
Fayette
West Shelby
West Shelby
West Shelby
West Shelby
West Shelby
West Shelby
West Shelby
West Shelby
West Shelby
East Shelby
Total
Depth
297
297
297
297
296
297
296
297
297
297
247
296
270
295
295
285
297
295
296
297
271
297
297
211
217
281
297
244
295
295
297
1422
514
552
451
751
750
830
733
540
232
Log
Rank
10
10
10
10
10
10
10
10
10
10
9
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
9
8
8
8
8
8
8
8
10
8
Location
Rank
7
7
7
7
7
7
7
7
7
7
7
7
7
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
6
6
6
6
6
6
6
6
6
1
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
TN157_000086
TN157_000088
TN157_000104
TN157_000105
TN157_000106
TN157_000107
TN157_000108
TN157_000109
TN157_000110
TN157_000111
TN157_000112
TN157_000113
TN157_000114
TN157_000116
TN157_000119
TN157_000122
TN157_000123
TN157_000124
TN157_000125
TN157_000128
TN157_000129
TN157_000130
TN157_000272
TN157_000273
TN157_000275
TN157_000276
TN157_000278
Longitude
-89.93508
-89.92898
-89.93022
-89.92464
-89.93051
-89.93148
-89.92761
-89.92472
-89.92938
-89.91064
-89.92592
-89.92990
-89.92215
-89.92627
-89.93066
-89.92870
-89.97731
-89.87580
-89.99398
-89.97287
-89.92990
-89.93308
-89.96704
-89.94315
-89.93473
-89.96120
-89.99732
Latitude
35.12385
35.08842
35.10700
35.11391
35.11172
35.12342
35.10693
35.09965
35.10275
35.10926
35.10759
35.10002
35.11452
35.11726
35.12530
35.11704
35.00676
35.04180
35.04259
35.02065
35.12023
35.12035
35.17315
35.12759
35.12611
35.15398
35.15759
Elevation
(ft)
305
265
280
295
278
311
300
285
278
312
285
273
297
305
260
308
320
300
281
311
295
285
248
275
305
248
258
State
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
County
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
East Shelby
South Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
Central
Shelby
West Shelby
Total
Depth
538
915
1226
870
860
340
557
914
943
619
618
912
865
622
428
855
1250
1278
408
816
595
1560
472
586
551
1440
744
Log
Rank
10
7
10
10
10
10
10
10
10
8
8
10
10
10
8
10
9
10
10
10
10
10
7
6
7
7
7
Location
Rank
6
2
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
1
2
1
6
6
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
TN157_000280
TN157_000281
TN157_000310
TN157_000315
TN157_000343
TN157_000355
TN157_000357
TN157_000358
TN157_000359
TN157_000363
TN157_000364
TN157_000374
TN157_000375
TN157_000376
TN157_000377
TN157_000378
TN157_000393
TN157_000431
TN157 000432
REF2
TN157_000433
TN157_000434
TN157_000435
TN157_000436
TN157_000437
TN157_000438
TN157_000439
TN157_000440
TN157_000441
TN157_000442
TN157_000445
TN157_000446
TN157_000447
TN157_000448
TN157_000449
Longitude
-89.95625
-89.94658
-89.85370
-89.84564
-89.80703
-89.71764
-89.71104
-89.72454
-89.72070
-89.72802
-89.71925
-89.71107
-89.72842
-89.71119
-89.72842
-89.71675
-89.97870
-89.65867
-89.74035
-89.72146
-89.75080
-89.71230
-89.68036
-89.74553
-89.74156
-89.70852
-89.67937
-89.65817
-89.65066
-89.76705
-89.68680
-89.75971
-89.69565
-89.75574
Latitude
35.24430
35.24698
35.15037
35.19564
35.15953
35.14887
35.14268
35.14606
35.14658
35.14315
35.13648
35.14000
35.12703
35.14537
35.12704
35.11176
35.27064
35.04652
35.29335
35.05956
35.06496
35.11840
35.11500
35.12781
35.17550
35.14890
35.16286
35.28545
35.23097
35.22267
35.28470
35.27349
35.04730
35.28901
Elevation
(ft)
300
232
270
305
295
349
362
343
360
315
325
352
276
370
330
335
240
390
269
321
371
331
350
305
302
381
375
324
293
394
282
252
361
253
State
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
County
Central
Shelby
Central
Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
Central
Shelby
SouthEast
Shelby
NorthEast
Shelby
SouthEast
Shelby
SouthEast
Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
East Shelby
NorthEast
Shelby
East Shelby
NorthEast
Shelby
NorthEast
Shelby
NorthEast
Shelby
SouthEast
Shelby
NorthEast
Shelby
Total
Depth
904
1500
267
587
512
1238
1219
1210
1291
1213
1276
1216
824
792
1200
815
490
295
297
296
296
263
297
295
256
237
296
297
297
264
297
297
297
296
Log
Rank
9
7
8
7
9
9
9
9
9
9
9
10
10
10
10
10
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
Location
Rank
6
6
6
2
6
6
6
6
6
6
6
6
6
6
6
6
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
TN157_000450
TN157_000451
TN157_000452
TN157_000453
TN157_000454
TN157_000455
TN157_000456
TN157_000457
TN157_000458
TN157_000459
TN157_000460
TN157_000461
TN157_000462
TN157_000463
TN157_000464
TN157_000465
TN157_000466
TN157_000467
TN157_000468
TN157_000469
TN157_000470
TN157_000472
TN157_000473
TN157_000474
TN157_000475
TN157_000476
TN157_000477
TN157_000478
Longitude
-89.72847
-89.70903
-89.72801
-89.75613
-89.77766
-89.78946
-89.67992
-89.75722
-89.82419
-89.86174
-89.90719
-89.74303
-89.94329
-89.72196
-89.97755
-89.99427
-90.04175
-90.03102
-89.99742
-89.96386
-89.92736
-89.84858
-89.89192
-89.82190
-89.77800
-89.74725
-89.70920
-89.70281
Latitude
35.29386
35.30133
35.30555
35.30453
35.29519
35.28932
35.00669
35.00565
35.28986
35.28975
35.29693
35.31127
35.31142
35.31976
35.28540
35.29103
35.28819
35.34162
35.34083
35.34071
35.34920
35.33692
35.38652
35.34383
35.34151
35.34413
35.31233
35.33727
Elevation
(ft)
272
285
355
269
295
260
375
345
275
246
289
330
300
375
292
245
322
402
320
284
278
284
294
298
312
308
281
341
State
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
County
NorthEast
Shelby
NorthEast
Shelby
NorthEast
Shelby
NorthEast
Shelby
NorthEast
Shelby
North Shelby
SouthEast
Shelby
SouthEast
Shelby
North Shelby
North Shelby
NorthCentral
Shelby
NorthEast
Shelby
NorthCentral
Shelby
NorthEast
Shelby
NorthCentral
Shelby
NorthCentral
Shelby
NorthWest
Shelby
NorthWest
Shelby
NorthWest
Shelby
NorthCentral
Shelby
NorthCentral
Shelby
NorthCentral
Shelby
North Shelby
North Shelby
NorthEast
Shelby
NorthEast
Shelby
NorthEast
Shelby
NorthEast
Shelby
Total
Depth
297
297
287
297
297
297
216
296
205
295
255
297
295
297
235
295
295
295
295
297
297
257
297
297
267
297
297
295
Log
Rank
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
Location
Rank
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------
Table App4.    Rankings of well logs including that for assessing the log, location and elevation (cont.)
Well ID
TN157_000479
TN157_000480
TN157_000481
TN157_000482
TN157_000483
TN157_000484
TN157_000485
TN157_000565
TN157_002033
TN157_002054
TN157_002359
Longitude
-89.76712
-89.72868
-89.67812
-89.67185
-90.06807
-90.08771
-90.12049
-90.02735
-89.76675
-89.80703
-89.93045
Latitude
35.39560
35.39571
35.38051
35.33891
35.40388
35.45958
35.45983
35.16560
35.12509
35.12592
35.11637
Elevation
(ft)
412
340
376
309
231
231
220
245
257
262
297
State
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
TN
County
North Shelby
NorthEast
Shelby
NorthEast
Shelby
NorthEast
Shelby
NorthWest
Shelby
NorthWest
Shelby
NorthWest
Shelby
West Shelby
East Shelby
East Shelby
Central
Shelby
Total
Depth
297
297
287
295
295
257
295
1520
475
295
1516
Log
Rank
9
9
9
9
9
9
9
9
10
10
7
Location
Rank
2
2
2
2
2
2
2
6
6
6
8
Elevation
Rank
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low

-------

-------
                                                                                                                          9.0
                                                                                               Appendix  Gaj
Station ID: 1
Station ID: 3
 DESCRIPTION:
    Latitude 35°18'39.U",  Longitude 89°38'22.13"  NAD27
    Shelby County, Tennessee, Hydrologic Unit 08010209
    Drainage area: 262 square miles
    Datum of gage: 246.43 feet above sea level NGVD29.

 AVAILABLE DATA:
DESCRIPTION:
    Latitude 35°10'09.41",  Longitude 89°51'57.74"  NAD27
    Shetby County, Tennessee, Hydrologic Unit 08010210
    Drainage area: 30.5 square miles

AVAILABLE DATA:
Data Type Begin Date
Real-time
End Date
Count )
-- Previous 60 days —
Daily Data )
Discharge, cubic feet per second
Gage height, feet
1969-10-01
1994-10-01
2008-11-25
2008-11-25
Daflv Statistics
Discharge, cubic feet per second
Gage height, feet
1969-10-01
2007-09-30
1994-10-01 | 2007-09-30
Monthly-Statistics
Discharge, cubic feet per second
Gage height, feet
1969-10
1994-10
Annual Statistics
2007-09
2007-09
Discharge, cubic feet per second 1970 2007
Gage height, feet
1995 | 2007
Peak streamflow | 1970-04-26 | 2007-01-15
Field measurements
1983-09-29 | 2008-10-06
Field/Lab water-duality samples | 1975-10-17 | 2005-08-16
22419 |
20580 |

13879 1
4725 i



38 |
243 |
171 |
Additional Data Sources
Annual Water Data Report (pdf)
Begin Date
**offsite**| 2006
End Date
2006
Count
1
Data Type
Real-time
Begin Date
— Prev
End Date
Count
ous 60 days —
Daily Data
Discharge, cubic feet per second
Gage height, feet
1996-04-01
1996-04-16
2008-11-25
2008-11-25
4596
17748
Daily Statistics
Discharge, cubic feet per second
Gage height, feet
Monthly Statistics
Discharge, cubic feet per second
Gage height, feet
Annual Statistics
Discharge, cubic feet per second
Gage height, feet
Peak streamflow
Field measurements

Additional Data Sources
Annual Water Data Report (pdf) **offsite**
1996-04-01
1996-04-16
2007-09-30
2007-09-30
4200
4041

1996-04
1996-04
2007-09
2007-09

1996
1996
1996-06-09
1996-03-07
1996-02-28
Begin Date
2006
2007
2007
2007-02-24
2008-10-08
2005-07-21
End Date
2006





12
128
205
Count
1
Ref, http://waterdata,usgs,gov/nwis/nwisman/?site no=07030240
       (Dec. 2008)
Station ID: 2
DESCRIPTION:
    Latitude 35°11<16",  Longitude 89°58'32"  NAD27
    Shelby County, Tennessee, Hydrologic Unit 08010210
    Drainage area: 788 square miles
    Datum of gage: 191.2 feet above sea level  NGVD29.

AVAILABLE DATA:
Data Type
Real-time
Begin Date
— Previ
End Date
ous 60 days -
Count
Daily Data
Discharge, cubic feet per second
Gage height, feet
1995-02-01
2004-10-01
2008-11-25
2008-11-25
4820
1340
D.iily Statistics
Discharge, cubic feet per second
Gage height, feet
1995-02-01
2004-10-01
2007-09-30
2007-09-30
4425
945
Monthly Statistics
Discharge, cubic feet per second
1995-02
2007-09
Gage height, feet | 2004-10 j 2007-09


Annual Statistics
Discharge, cubic feet per second
Gage height, feet
Peak streamflow
Field measurements
Field/Lab water-quaKtv samples
Additional Data Sources
1995
2007
2005 j 2007
2001-02-16
1985-10-29
1995-04-27
Begin Date
Annual Water Data Report (pdf) **offsite**| 2006
2006-12-31
2008-11-19
2005-07-25
End Date
2006


7
126
40
Count
1
                                                                     Ref. http://waterdata.usgs.gov/nwis/nwisman/7site  no=07031692
                                                                             (Dec. 2008)
Station ID: 4
DESCRIPTION:
    Latitude 35°06'59",  Longitude 89°48'05" NAD27
    Shelby County, Tennessee, Hydrologic Unit 08010210
    Drainage area: 699 square miles
    Datum of gage: 235.76 feet above sea level  NGVD29.

AVAILABLE DATA:
Data Type
Real-time
Begin Date
End Date
Count
- Previous 60 days -
Daily Data
Discharge, cubic feet per second
Gage height, feet
1969-10-01
1991-01-01
2008-11-25
2008-11-25
12823
6320
DaBy Statistics
Discharge, cubic feet per second
Gage height, feet
1969-10-01
1991-01-01
2007-09-30
2007-09-30
12416
5916
Monthly Statistics
Discharge, cubic feet per second
Gage height, feet
Annual Statistics
Discharge, cubic feet per second
Gage height, feet
Peak streamflow
Field measurements
Field/Lab water-quality samples
Additional Data Sources
Annual Water Data Report Ipdf) **offsite**
1969-10
1991-01
2007-09
2007-09



1970
1991
1970-04-26
1970-01-02
1975-10-23
Begin Date
2006
2007
2007


2007-02-23 | 34
2008-10-14
184
2005-08-23 | 155
End Date
2006
Count
1
Ref. http://waterdata.usgs.gov/nwis/nwisman/7site no=07031740
       (Dec. 2008)
                                                                     Ref, http://waterdata.usgs.gov/nwis/nwisman/7site  no=0703W50
                                                                             (Dec. 2008)

-------
Station ID: 5
Station ID:  8
DESCRIPTION:
    Latitude 35°02'59",  Longitude 89°49'OB"  NAD27
    Shelby County, Tennessee, Hydrologic Unit 08010211
    Drainage area: 68.2 square miles
    Datum of gage: 262.92 feet above sea level  NGVD29.

AVAILABLE DATA:
Data Type
Daily Data
Discharge, cubic feet per second
Begin Date
End Date
Count
— Previous 60 days —
_______ ,.______ j-^j^
DalbLStatistics
Discharge, cubic feet per second
1969-10-01
2007-09-30 | 13144
Monthly Statistics
Discharge, cubic feet per second
1969-10
2007-09

Annual Statistics
Discharge, cubic feet per second
1970
Peak streamflow | 1970 03 03
Fieid measurements [l983~Q9-28
Fieid/Lab water-quality samples
Additional Data Sources
2007
2007-02-24
2008-10-14

37
229
1975-10-23 [2005-08-23 [ 165
Begin Date
End Date
Annual Water Data Report (pdf) **offsite**| 2006 | 2006
Count
1
DESCRIPTION:
    Latitude 35°01'57", Longitude 89°14'48'  NAD27
    Fayette County, Tennessee, Hydrologlc Unit 08010210
    Drainage area: 210 square miles
    Contributing drainage area: 210 square miles,

AVAILABLE DATA:
Ref, http://waterdata.usgs.gov/nwis/nwisman/7site no=07032200
        (Dec. 2008)
Data Type
Real-time
Daily Data
Temperature, water, degrees Celsius
Discharge, cubic feet per second
Gage height, feet
Daily Statistics
Temperature, water, degrees Celsius
Discharge, cubic feet per second
Gage height, feet
Monthly Statistics
Temperature, water, degrees Celsius
Discharge, cubic feet per second
Gage height, feet
Annual Statistics
Temperature, water, degrees Celsius
Discharge, cubic feet per second
Gage height, feet
Peak streamflow
Field measurements
Field/Lab water-quality samples
Additional Data Sources
Annual Water Data Report (pdf) **offsite**
Begin Date
End Date
Count
— Previous 60 days —

1996-09-18
1995-09-01
1995-08-23

1996-09-18
1995-09-01
1995-08-31

1996-09
1995-09
1995-08

1996
1995
1995
1996-03-27
1995-08-16
1995-10-04
Begin Date
2006
2008-11-18
2008-11-25
2008-11-25

2007-09-30
2007-09-30
2007-09-30

2007-09
2007-09
2007-09

2007
2007
2007
2007-01-06
2008-10-09
2008-07-22
End Date
2006
3099
4828
16515

630
4048
3938








12
104
241
Count
1
Station  ID: 6
 DESCRIPTION:
     Latitude 35°06'34",   Longitude 89°39'28"  NAD83
     Shelby County, Tennessee, Hydrologic Unit 08010210
     Drainage area: 3.61 square miles

 AVAILABLE DATA:
Data Type
Real-time
Field/Lab water-quality samples
Begin Date
End Date
Count
— Previous 60 days —
2007-11-23
2008-07-09
55
                                                                          Ref, http://waterdata,usgs,gov/nwis/nwisman/?site  no=07030392
                                                                                  (Dec. 2008)
Station ID:  9
                                                                           DESCRIPTION:
                                                                              Latitude 35°16'30.89",  Longitude 88°58'35.65"  NAD27
                                                                              Hardeman County, Tennessee, Hydrologic Unit 08010208
                                                                              Drainage area: 1,480 square miles
                                                                              Datum of gage: 323.49 feet above sea level  NGVD29.

                                                                           AVAILABLE DATA:
Ref. http://waterdata.usgs.gov/nwis/nwisman/7site no=07036050
        (Dec. 2008)
Station ID: 7
DESCRIPTION:
    Latitude 35°03'15",  Longitude 89°32'28"  NAD27
    Fayette County, Tennessee, Hydrologic Unit 08010210
    Drainage area: 503 square miles
    Datum of gage: 300.74 feet above sea level  NGVD29.

AVAILABLE DATA:
Data Type
Real-time
Begin Date
End Date
Count
- Previous 60 days —
Daily Data
Discharge, cubic feet per second
Gage height, feet
1929-08-01
2001-05-25
2007-09-30 i 21177
2008-11-25
7881
Daily Statistics
Discharge, cubic feet per second
Gage height, feet
1929-08-02 j 2007-09-30 | 17478
2001-05-25
2007-09-30 1 1849
Monthly Statistics
Discharge, cubic feet per second
Gage height, feet
1929-08
2001-05
2007-09
2007-09


Annual Statistics
Discharge, cubic feet per second
1929
2007

Gage height, feet [2001 | 2007 f
Peak streamflow
Field measurements
Field/Lab water-aualitv samples
Additional Data Sources
Annual Water Data Report (pdf) "offsite**
1930-01-09
2001-06-18
1961-08-16
Begin Date
2006
2006-01-24
47
2008-10-15 [ 61
2006-05-25
End Date
2006
65
Count
1
Data Type
Real-time
Begin Date
End Date
Count
— Previous 60 days —
Daly Data
Discharge, cubic feet per second
Gage height, feet
1929-08-01 | 2008-11-25 | 28971
1989-02-20
2008-11-25
6617
Daly Statistics
Discharge, cubic feet per second
Gage height, feet
1929-08-01
1989-02-20
2007-09-30
2007-09-30
28550
6196
Monthly Statistics
Discharge, cubic feet per second
Gage height, feet
1929-08
2007-09
1989-02 | 2007-09


Annual Statistics
Discharge, cubic feet per second
Gage height, feet
Peak streamflow
Field measurements
Field/Lab water-auaBtv samples
Additional Data Sources
1929
1989
1930-01-09
1983-09-07
1964-05-14
Begin Date
Annual Water Data Report (pdf) **offsite**[2uu6
2007
2007
2007-01-10
2008-10-03
2006-05-30
End Date
2006


77
198
269
Count
1
                                                                          Ref. http://waterdata.usgs.gov/nwis/nwisman/7site  no=07029500
                                                                                  (Dec. 2008)
Ref, http://waterdata.usgs.gov/nwis/nwisman/7site no=07030550
        (Dec. 2008)

-------
Station ID: 10
DESCRIPTION:
    Latitude 35°38'14.12",  Longitude 89°36'33.76"  NAD27
    Tipton County, Tennessee, Hydrologic Unit 08010208
    Drainage area: 2,308 square miles
    Datum of gage: 239.81 feet above sea level  NGVD29.

AVAILABLE DATA:
Data Type
Real-time
Begin Date
End Date
Count
— Previous 60 days —
Daily Data
Discharge, cubic feet per second
1939-01-07
2008-11-25
19880
Daily Statistics
Discharge, cubic feet per second
1939-01-07
2007-09-30
19458
Monthly Statistics
Discharge, cubic feet per second
Annual Statistics
Discharge, cubic feet per second
Peak streamflow
Field measurements
Field/Lab water quality samples
Additional Data Sources
Annual Water Data Renort f odf) "offsite"
1939-01 j 2007-09
1939
1937-00-00
2003-02-27
1977-02-10
Begin Date
2006
2007
2007-01-17
2008-10-15
2008-07-11
End Date
2006

44
44
68
Count
1
Ref, http://waterdata,usgs,gov/nwis/nwisman/?site no=07030050
        (Dec. 2008)
Station ID: 11
DESCRIPTION:
    Latitude 34°54'27",  Longitude 89°45'12"  NAD83
    De Soto County, Mississippi, Hydrologic Unit 08030204
    Drainage area: 191 square miles
    Contributing drainage area: 191 square miles.
    Datum of gage: 280 feet above sea level  NGVD29.

AVAILABLE DATA:
Data Type
Real time
Begin Date
End Date
— Previous 60 days
|Count

Daily Data
Discharge, cubic feet per second
Gage height, feet
1996-06-13
2008-11-25
1996-06-13 j 2008-11-25
[ 4540
J4286
Daily Statistics
Discharge, cubic feet per second
Gage height, feet
1996-10-01
1996-10-01
2007-09-30
2007-09-30
J4017
| 3763
Monthly Statistics
Discharge, cubic feet per second
Gage height, feet
Annual Statistics
Discharge, cubic feet per second
Gage height, feet
Peak streamflow
Field measurements
Field/Lab water-aualitv samples
Additional Data Sources
Annual Water Data Report (pdf) "offsite**
1996-10
2007-09 |
1996-10 | 2007-09

1997
1997

2007 |
2007 |
1997-03-03 j 2006-01-23
1954-10-15 j 2008-1 1-19
1972-06-14
Begin Date
2006
1972-06-14
End Date
2007
i 10
i 121
| 1
|Count
| 2
Ref, http://waterdata,usgs,gov/nwis/nwisman/?site no=07275900
        (Dec. 2008)

-------

-------
           10.0
Appendix Geo-sites

-------
Table App5.   Loosahatchie/SR 14 Hydraulic Conductivity BR-18
Boring (BR-1 8)
Drilling Elevation 72.5 m
Boring Bottom Elev. 48.1 m
Riverbed Elev. 67.2 m
Ground Water Elev. N/A
Soil Type
Silty Clay
Silty Sand
Silty Clay
Sand and Gravel
Sandy Clay and Gravel
High Plasticity Clay
Description
brown and gray, medium
to stiff
gray, dense condition
gray stiff
tan and gray, traces of
wood, dense to very
dense condition
brown and orange,
medium condition
gray, contains silt and
sand seams, very stiff
to hard
Boring Station 15+782
River Center Station 1 5+91 0
Boring Distance 128 m
Elevation Range (m)
72.5 to 67.5
67.5 to 65.1
65.1 to 64.8
64.8 to 61.3
61.3 to 58.5
58.5 to 48.1
Layer
Thickness (m)
5.0
2.4
0.3
3.5
2.8
10.4
Estimated k
(m/day)
0.0864 to
0.000864
0.864 to
0.000864
0.0864 to
0.000864
> 8.64
0.864 to
0.000864
0.000864 to
0.00000864
Table App6.   Loosahatchie/SR 14 Hydraulic Conductivity BR-19
Boring (BR-1 9)
Drilling Elevation 72.6 m
Boring Bottom Elev. 48.2 m
Riverbed Elev. 67.2 m
Ground Water Elev. 67.4 m
Soil Type
Silty Clay
Sand
Sand and Gravel
Clay
High Plasticity Clay
Sandy Clay
Description
brown and gray, stiff
brown, contains clay
seams, medium to very
dense condition
gray and tan, medium to
very dense condition
tan stiff
gray, contains silt and
sand seams, stiff to hard
gray , very stiff
Boring St. 15+814
River Center St. 15+910
Boring Distance 96 m
Elevation Range (m)
72.6 to 70.6
70.6 to 66.0
66.0 to 61.6
61.6 to 59.1
59.1 to 51.6
51.6 to 48.2
Layer Thickness
(m)
2.0
4.6
4.4
2.5
7.5
3.4
Estimated k
(m/day)
0.0864 to
0.000864
> 0.864
>8.64
0.0864 to
0.000864
0.000864 to
0.00000864
0.000864 to
0.00000865

-------
Table App7.   Loosahatchie/SR 14 Hydraulic Conductivity BR-20
Boring (BR-20)
Drilling Elevation 72.7 m
Boring Bottom Elev. 48.3 m
Riverbed Elev. 67.2 m
Ground Water Elev. N/A
Soil Type
Silty Sand (SM)
Clayey Silt
w/ Sand (ML)
Silty Sand (SM)
Sand and Gravel
Sandy Gravel
High Plasticity Clay
w/ Gravel
High Plasticity Clay
Description
brown and gray,
medium to stiff
gray, dense condition
gray stiff
gray and brown, very
dense condition
gray and brown,
dense condition
tan and gray,
very stiff
gray, contains sand
and lignite, very stiff
to hard
Boring St. 15+846
River Center St. 15+910
Boring Distance 64 m
Elevation Range (m)
72.7 to 71.7
71.7 to 67.7
67.7 to 62.7
62.7 to 60.5
60.5 to 58.7
58.7 to 57.0
57.0 to 53.7
Layer
Thickness (m)
1.0
4.0
5.0
2.2
1.8
1.7
3.3
Estimated k
(m/day)
0.864 to 0.000864
0.864 to 0.000864
0.864 to 0.000864
> 8.64
> 8.64
0.000864 to
0.00000864
0.000864 to
0.00000864
Table App8.   Loosahatchie/SR 14 Hydraulic Conductivity BR-23
Boring (BR-23)
Drilling Elevation 72.8 m
Boring Bottom Elev. 48.4 m
Riverbed Elev. 67.2 m
Ground Water Elev. N/A
Soil Type
Silty Clay
Sandy Clay
Sand
Gravel w/ Sand (GW)
Clay
High Plasticity Clay
Description
brown, soft to very stiff,
brown and gray
gray, dense condition
gray, medium condition
gray, very dense condition
orange and gray, contains
gravel, very stiff
gray, contains silt and
sand seams, very stiff to
hard
Boring St. 15+944
River Center St. 15+910
Boring Distance 34 m
Elevation Range (m)
72.8 to 66.8
66.8 to 64.8
64.8 to 62.8
62.8 to 60.0
60.0 to 58.8
58.8 to 48.4
Layer Thickness
(m)
6.0
2.0
2.0
2.8
1.2
10.4
Estimated k
(m/day)
0.000864 to
0.00000864
0.000864 to
0.00000864
> 8.64
>8.64
0.000864 to
0.00000864
0.000864 to
0.00000864

-------
Table App9.   Loosahatchie/SR 14 Hydraulic Conductivity BR-24
Boring (BR-24)
Drilling Elevation 72.5 m
Boring Bottom Elev. 48.1 m
Riverbed Elev. 67.2 m
Ground Water Elev. 66.4 m
Soil Type
Silty Clay (CL-ML)
Sandy Clay
Sand w/ Silt (SP-SM)
Sand and Gravel
High Plasticity Clay
Lignitic Silty Clay
Description
brown and gray, stiff to
very stiff
brown and gray, stiff
gray, medium condition
gray and tan, dense to
very dense condition
gray, stiff to hard, contains
sand
dark gray to black, hard
Boring St. 15+980
River Center St. 15+910
Boring Distance 70 m
Elevation Range (m)
72.8 to 69.2
69.2 to 67.8
67.8 to 63.6
63.6 to 60.6
60.6 to 49.8
49.8 to 48.1
Layer Thickness
(m)
3.6
1.4
4.2
3.0
10.8
1.7
Estimated k
(m/day)
0.864 to
0.00000864
0.000864 to
0.00000864
0.864 to
0.000864
> 8.64
0.000864 to
0.00000864
0.000864 to
0.00000864
Table ApplO.  Wolf/ SR 3 Hydraulic Conductivity B-7
Boring (B-7)
Drilling Elevation 58.8 m
Boring Bottom Elev. 34.4 m
Riverbed Elev. 54.9 m
Ground Water Elev. N/A
Soil Type
Rip-Rap and Sand
Sand and Gravel
Clay (CL)
High Plasticity Clay
Sandy Silty Clay (CL-ML)
High Plasticity Clay
Sand
Description
N/A
tan, dense condition
Gray, very stiff
Gray, very stiff
gray, contains lignite,
very stiff
gray contains lignite,
hard
gray, contains lignite,
very dense condition
Boring St. 5+97
River Center St. 6+55
Boring Distance 58 m
Elevation Range (m)
58.8 to 53.5
53.5 to 52.0
52.0 to 49.0
49.0 to 42.0
42.0 to 39.0
39.0 to 36.0
36.0 to 34.4
Layer
Thickness (m)
5.3
1.5
3.0
7.0
3.0
3.0
1.6
Estimated k
(m/day)
> 8.64
> 8.64
0.000864 to
0.00000864
0.000864 to
0.00000864
0.000864 to
0.00000865
0.000864 to
0.00000866
> 8.64

-------
Table App11.  Wolf/ SR 3 Hydraulic Conductivity B-8
Boring (B-8)
Drilling Elevation 61.1 m
Boring Bottom Elev. 36.7 m
Riverbed Elev. 54.9 m
Ground Water Elev. 55.6 m
Soil Type
Rip-Rap and Sand
Sand (SP)
Silty Sandy Clay
High Plasticity Clay
Clayey Silt (ML)
High Plasticity Clay
Description
N/A
gray, loose to medium
condition
gray, traces of gravel,
very stiff
gray, very stiff
gray, very stiff
gray, hard
Boring St. 6+40
River Center St. 6+55
Boring Distance 15m
Elevation Range (m)
61.1 to 55.6
55.6 to 53.2
53.2 to 51.4
51.4 to 48.4
48.4 to 47.1
47.1 to 36.7
Layer
Thickness (m)
5.5
2.4
1.8
3.0
1.3
10.4
Estimated k
(m/day)
>8.64
>8.64
0.000864 to
0.00000865
0.000864 to
0.00000866
0.864 to
0.000864
0.000864 to
0.00000866
Table App12.  Wolf/ SR 3 Hydraulic Conductivity B-12
Boring (B-1 2)
Drilling Elevation 63.4 m
Boring Bottom Elev. 39.0 m
Riverbed Elev. 54.9 m
Ground Water Elev. N/A
Soil Type
Rip-Rap and Sand
Clayey Silt
High Plasticity Clay
(CH)
Sand
Sand w/ Gravel (SP)
High Plasticity Clay
Description
N/A
brown, very stiff
Gray, soft
tan, medium to
dense condition,
clay seams
gray, medium to
dense condition
gray, contains silty
sand seams, very
stiff to hard
Boring St. 6+71
River Center St. 6+55
Boring Distance 16 m
Elevation Range (m)
63.4 to 61.0
61.0 to 59.7
59.7 to 58.4
58.4 to 55.4
55.4 to 51.3
51.3 to 39.0
Layer
Thickness (m)
2.4
1.3
1.3
3.0
4.1
12.3
Estimated k
(m/day)
>8.64
0.864 to
0.000864
0.000864 to
0.00000866
> 8.64
>8.64
0.000864 to
0.00000866
Calculated k
(m/day)




14.65


-------
Table App13.  Wolf/ SR 3 Hydraulic Conductivity B-13
Boring (B-13)
Drilling Elevation 63.4 m
Boring Bottom Elev. 39.0 m
Riverbed Elev. 54.9 m
Ground Water Elev. 57.3 m
Soil Type
Clayey Silt
Clay
High Plasticity Clay
Clayey Silty Sand
Sand w/ Silt
(SP-SM)
High Plasticity Clay
Sandy Silty Clay
Description
brown, stiff to very
stiff
Brown, stiff
gray, silty sand
seams, stiff
brown and gray,
medium condition
gray, medium to
very dense condition
gray, contains silty
sand seams, very
stiff to hard
gray, hard
Boring St. 7+16
River Center St. 6+55
Boring Distance 61 m
Elevation Range (m)
63.4 to 61.6
61.6 to 61.0
61.0 to 59.5
59.5 to 58.3
58.3 to 52.5
52.5 to 43.7
43.7 to 39.1
Layer
Thickness
(m)
1.8
0.6
1.5
1.2
5.8
8.8
4.6
Estimated k
(m/day)
0.864 to
0.000864
0.000864 to
0.00000866
0.000864 to
0.00000866
0.000864 to
0.00000866
> 0.864
0.000864 to
0.00000866
0.000864 to
0.00000865
Calculated k
(m/day)




19.53


Table App14.  Wolf/ Walnut Grove Hydraulic Conductivity BB-23
Boring (BB-23)
Drilling Elevation 75.9 m
Boring Bottom Elev. 57.4 m
Riverbed Elev. 61 .0 m
Ground Water Elev. 70.1 m
Soil Type
Silty Clay (CL)
Clay
Silty Sand
Sand
Gravely Sand
Silty Clay
Clay
Description
brown in color, medium
consistency
gray in color, soft
consistency
gray in color, contains
some gravel, medium
condition
gray in color, medium
condition
gray in color, medium
condition
gray in color, contains
some traces of sand from
40'; very stiff consistency
gray in color, contains
traces of sand and lignite,
very stiff consistency
Boring St. 71+04
River Center St. 71+37
Boring Distance 33 m
Elevation Range (m)
75.9 to 73.2
73.2 to 70.4
70.4 to 69.2
69.2 to 67.7
67.7 to 66.5
66.5 to 61.0
61.0 to 57.4
Layer
Thickness (m)
2.7
2.7
1.2
1.5
1.2
5.5
3.6
Estimated k
(m/day)
0.000864 to
0.00000864
0.000864 to
0.00000864
0.864 to 0.000864
> 0.864
> 0.864
0.000864 to
0.00000864
0.000864 to
0.00000864

-------
Table App15.  Wolf/ Walnut Grove Hydraulic Conductivity BB-26
Boring (BB-26)
Drilling Elevation 75.0 m
Boring Bottom Elev. 56.7 m
Riverbed Elev. 61 .0 m
Ground Water Elev. 70.7 m
Soil Type
Silty Clay (CL)
Sand
Sandy Clayey Silt
Sand
Clay
Description
brown in color, contains
organic matter, soft
consistency
brown and white in color,
loose to medium condition
gray in color contains
organic matter, medium
consistency
gray in color, contains
occasional gravel,
medium condition
gray in color, very stiff to
hard consistency
Boring St. 71+78
River Center St. 71+37
Boring Distance 41 m
Elevation Range (m)
75.0 to 72.7
72.7 to 69.2
69.2 to 68.7
68.7 to 64.9
64.9 to 56.7
Layer Thickness
(m)
2.3
3.5
0.5
3.8
8.2
Estimated k
(m/day)
0.000864 to
0.00000864
> 0.864
0.864 to 0.000864
> 0.864
0.000864 to
0.00000864
Table App16.  Wolf/ Walnut Grove Hydraulic Conductivity BB-29
Boring (BB-29)
Drilling Elevation 75.6 m
Boring Bottom Elev. 57.3 m
Riverbed Elev. 61 .0 m
Ground Water Elev. 70.1 m
Soil Type
Silty Sand (SM)
Sand
Sand w/ Gravel
Sandy Clay
Clay
Description
brown in color, loose
condition
brown in color, medium
condition
brown in color, contains
clay seams from 11.6m,
medium condition
gray in color, very stiff
consistency
gray in color, contains
lignite to 1 7.7 m, very stiff
consistency
Boring St.
River Center St. 71+37
Boring Distance
Elevation Range (m)
75.6 to 73.2
73.2 to 65.6
65.6 to 62.2
62.2 to 61.0
61.0 to 57.3
Layer Thickness
(m)
2.4
7.6
3.4
1.2
3.7
Estimated k
(m/day)
0.864 to 0.000864
> 0.864
> 0.864
0.000864 to
0.00000864
0.000864 to
0.00000864

-------
Table App17.  Nonconnah/Near Riverport Hydraulic Conductivity B-1
Boring (B-1)
Drilling Elevation 68.0 m
Boring Bottom Elev. 49.5 m
Riverbed Elev. 53.3 m
Ground Water Elev. N/A
Soil Type
Clayey Silt (ML)
Silty Clay (CL)
Clayey Silt (ML)
Silty Clay (CL)
N/A (Large amounts of wood
were encountered.)
Sand (SP) w/ gravel
Sand (SP)
Sand (SP)
Clayey Gravel (GP-GC)
Description
fill- brown and gray to
brown
fill- gray
fill- gray
fill- gray
No samples were taken
and no tests were run
medium dense to very
dense tan
very dense tan
medium dense brown
medium dense reddish
brown
Boring Station N/A
River Center Station N/A
Boring Distance 115.8 m
Elevation Range (m)
68.0 to 66.9
66.9 to 65.4
65.4 to 64.2
64.2 to 59.8
59.8 to 56.8
56.8 to 53.6
53.6 to 51.9
51.9 to 50.5
50.5 to 49.5
Layer
Thickness (m)
1.1
1.5
1.2
4.4
3.0
3.2
1.7
1.4
1.0
Estimated k
(m/day)






> 0.864


Table App18.  Nonconnah/Near Riverport Hydraulic Conductivity B-2
Boring (B-2)
Drilling Elevation 73.2 m
Boring Bottom Elev. 50.1 m
Riverbed Elev. 53.3 m
Ground Water Elev. N/A
Soil Type
Clayey Sand (SC)
Sand (SP)
Sandy Silt (ML)
Sand (SP)
Silty Clay (CL)
Sandy Silt (ML)
Silty Clay (CL)
Clay (CH)
Sandy Silt (ML)
Silty Sand (SM)
Sand (SC)
w/ gravel
Silty Sand
(SP-SM)
Description
medium dense brown
medium dense to dense
brown, some gravel
firm gray sandy
medium dense brown
firm gray silty
firm gray sandy
soft brown and gray
firm gray high plasticity
stiff gray sandy
dense gray silty
medium dense brown
clayey
medium dense brown and
gray silty
Boring Station N/A
River Center Station N/A
Boring Distance 182.9m
Elevation Range (m)
73.2 to 72.6
72.6 to 69.1
69.1 to 67.6
67.6 to 66.1
66.1 to 64.6
64.6 to 63.1
63.1 to 61.6
61.6 to 58.6
58.6 to 57.1
57.1 to 55.6
55.6 to 54.1
54.1 to 50.1
Layer Thickness
(m)
0.6
3.5
1.5
1.5
1.5
1.5
1.5
3.0
1.5
1.5
1.5
4.0
Estimated k
(m/day)








0.864 to 0.000864




-------
Table App19.  Nonconnah/Near Riverport Hydraulic Conductivity B-12
Boring (B-1 2)
Drilling Elevation 70.4 m
Boring Bottom Elev. 47.4 m
Riverbed Elev. 53.3 m
Ground Water Elev. N/A
Soil Type
Silty Sand (SM)
Sand (SP)
Silty Clay (CL)
Silty Sand (SM)
Clayey Silt (ML)
Clay (CH)
Clayey Silt (ML)
Sand (SP)
Sandy Gravel (GP)
Silty Sand (SM)
Description
medium dense brown
medium dense brown
stiff brown and gray
loose gray
soft gray
soft to stiff gray high
plasticity
firm gray
dense brown
medium dense brown
medium dense light
gray to brown and
light gray
Boring Station N/A
River Center Station N/A
Boring Distance 274.3 m
Elevation Range (m)
70.4 to 69.8
69.8 to 69.2
69.2 to 68.6
68.6 to 67.8
67.8 to 65.1
65.1 to 60.5
60.5 to 57.5
57.5 to 56.0
56.0 to 54.5
54.5 to 47.4
Layer Thickness
(m)
0.6
0.6
0.6
0.8
2.7
4.6
3.0
1.5
1.5
7.1
Estimated k
(m/day)









0.864 to 0.000864
Table App20.  Nonconnah/Airways Blvd Hydraulic Conductivity B-1
Boring (B-1)
Drilling Elevation 71.0 m
Boring Bottom Elev. 33.1 m
Riverbed Elev. 64.6 m
Ground Water Elev. 65.5 m
Soil Type
Rip Rap
Silt
Clayey Sand
Sandy Clay
Sand
Gravelly Sand
Sand
Gravelly Sand
Lignite/wood
Silty Sand
Description

brown to gray, stiff
gray, contains interbed-
ded clay seams
black and gray
tan, medium dense
condition
brown, medium dense
condition
brown, medium dense
condition, contains
gravel
brown, medium dense
condition

tan, medium dense
to dense condition,
contains clay
Boring Station 16+29.77
River Center Station 16+13.17
Boring Distance 16.6 m
Elevation Range (m)
71.0 to 69.6
69.6 to 67.8
67.8 to 67.0
67.0 to 66.7
66.7 to 65.5
65.5 to 64.0
64.0 to 59.4
59.4 to 57.9
57.9 to 57.0
57.0 to 33.1
Layer Thickness
(m)
1.4
1.8
0.8
0.3
1.2
1.5
4.6
1.5
0.9
23.9
Estimated k
(m/day)





> 0.864





-------
Table App21.  Nonconnah/Airways Blvd Hydraulic Conductivity B-2
Boring (B-2)
Drilling Elevation 70.4 m
Boring Bottom Elev. 35.4 m
Riverbed Elev. 64.6 m
Ground Water Elev. 66.1 m
Soil Type
Rip Rap
Silty Clay
Silt (ML)
Sand
Sand w/ gravel (SP)
Gravelly Sand
Sand (SP)
Clay
Description

brown and gray, stiff
brown and gray, medium
brown-gray, contains
gravel, dense condition
brown and gray, medium
dense condition
brown, dense condition
tan-brown, medium dense
condition, contains gravel
gray, very stiff to hard
contains sand
Boring Station 15+96.07
River Center Station 16+13.17
Boring Distance 17.1 m
Elevation Range (m)
70.4 to 68.9
68.9 to 68.0
68.0 to 66.8
66.8 to 66.5
66.5 to 65.0
65.0 to 63.5
63.5 to 42.2
42.2 to 35.4
Layer Thickness
(m)
1.5
0.9
1.2
0.3
1.5
1.5
21.3
6.8
Estimated k
(m/day)





> 0.864


Table App22.  Nonconnah/Knight Arnold Hydraulic Conductivity B-6
Boring (B-6)
Drilling Elevation 84.7 m
Boring Bottom Elev. 59.9 m
Riverbed Elev. 79.2 m
Ground Water Elev. N/A
Soil Type
Silty Clay
Silty Sand
Clayey Sand
Clay
Clay
Sandy Clay
Clay w/ sandy seams
Sand
Sand
Description
brown
gray
traces of gravel
reddish gray
gray-blue, some lignite
gray-yellow
gray and yellow
clean white
white and brown
Boring Station 5+70
River Center Station 6+49
Boring Distance 79 m
Elevation Range (m)
84.7 to 81.0
81.0 to 80.1
80.1 to 78.6
78.6 to 77.1
77.1 to 74.1
74.1 to 72.6
72.6 to 69.6
69.6 to 63.5
63.5 to 54.4
Layer Thickness
(m)
3.7
0.9
1.5
1.5
3.0
1.5
3.0
6.1
9.1
Estimated k
(m/day)


0.864 to 0.000864







-------
Table App23.  Nonconnah/Knight Arnold Hydraulic Conductivity B-7
Boring (B-7)
Drilling Elevation 82.0 m
Boring Bottom Elev. 57.6 m
Riverbed Elev. 79.2 m
Ground Water Elev. N/A
Soil Type
Silty Clay
Clayey Sand
Sand and Gravel
Clay
Clayey Sand
Clayey Sand
Sand
Sand
Description
brown
brown
brown w/ clay seams
gray, with lignite
gray, with lignite
brown and gray
white fine, w/ traces of
clay
white fine
Boring Station 6+14
River Center Station 6+49
Boring Distance 35 m
Elevation Range (m)
82.0 to 80.6
80.6 to 79.8
79.8 to 78.4
78.4 to 73.8
73.8 to 71.2
71.2 to 69.1
69.1 to 68.2
68.2 to 57.6
Layer Thickness
(m)
1.4
0.8
1.4
4.6
2.6
2.1
0.9
10.6
Estimated k
(m/day)


> 0.864





Table App24.  Nonconnah/Knight Arnold Hydraulic Conductivity B-8
Boring (B-8)
Drilling Elevation 86.0 m
Boring Bottom Elev. 55.8 m
Riverbed Elev. 79.2 m
Ground Water Elev. N/A
Soil Type
Clayey Silt
Silty Clay
Clayey Silt
Sand
Sand w/ Gravels
Sand
Clayey Sand
Clay
Sand
Sand
Sand
Description
brown
gray
brown and gray
white
red
clean, white
w/ sandy clay seams
gray
gray w/ clay lenses
gray w/ clay seams
clean, white
Boring Station 7+13
River Center Station 6+49
Boring Distance 64 m
Elevation Range (m)
86.0 to 85.1
85.1 to 84.5
84.5 to 80.8
80.8 to 79.9
79.9 to 78.4
78.4 to 72.3
72.3 to 70.8
70.8 to 67.8
67.8 to 64.8
64.8 to 58.8
58.8 to 55.8
Layer Thickness
(m)
0.9
0.6
3.7
0.9
1.5
6.1
1.5
3.0
3.0
6.0
3.0
Estimated k
(m/day)




> 0.864







-------
Table App25.  Wolf/ SR 194 Hydraulic Conductivity B-1
Boring (B-1)
Drilling Elevation 97.5 m
Boring Bottom Elev. 76.0 m
Riverbed Elev. 93.3 m
Ground Water Elev. 93.0 m
Soil Type
Clay (CL)
Silty Clay (CL-ML)
Clayey Sand (CL-ML)
Clay (CL)
Sandy Silt (ML)
Sand (SP-SC)
Sand (SC)
Silt (MH)
Sand (SP)
Description
stiff brown sandy lean
clay with trace gravel
stiff brown silty clay with
trace organics
loose brown clayey sand
with trace gravel
stiff brown and gray lean
clay
very stiff brown sandy silt
with trace gravel
medium dense tan sand
with clay
medium dense tan clayey
sand
firm black elastic silt with
sand and trace organics
dense tan sand, to
medium dense tan
Boring St. 6+07
River Center St. 7+39
Boring Distance 132 m
Elevation Range (m)
97.5 to 95.2
95.2 to 93.7
93.7 to 92.2
92.2 to 90.7
90.7 to 89.2
89.2 to 87.7
87.7 to 86.2
86.2 to 84.7
84.7 to 81.6
Layer Thickness
(m)
2.3
1.5
1.5
1.5
1.5
1.5
1.5
1.5
3.1
Estimated k
(m/day)
0.000864 to
0.00000864
0.864 to 0.000864
0.864 to 0.000864
0.000864 to
0.00000864
0.864 to 0.000864
> 0.864
0.000864 to
0.00000864
0.0864 to 0.000864
> 0.864

-------
Table App26.  Wolf/ SR 194 Hydraulic Conductivity B-2
Boring (B-2)
Drilling Elevation 97.5 m
Boring Bottom Elev. 76.0 m
Riverbed Elev. 93.3 m
Ground Water Elev. 89.9 m
Soil Type
Clay (CL)
Silty Clay (CL-ML)
Clay (CL)
Silty Clay (CL-ML)
Silty Clayey Sand (SC-SM)
Sand (SP)
Clayey Sand (SC)
Sand (SP)
Clayey Sand (SC)
Description
very stiff brown sandy
lean clay with trace
gravel
firm brown silty clay with
sand and trace gravel
soft gray lean clay with
trace gravel
stiff brown and gray silty
clay
medium dense brown
and gray
medium dense tan and
gray
medium dense brown
medium dense brown
with trace gravel
medium dense tan with
trace gravel
Boring St. 8+74
River Center St. 7+39
Boring Distance 135 m
Elevation Range (m)
97.5 to 95.2
95.2 to 93.7
93.7 to 92.2
92.2 to 90.7
90.7 to 89.2
89.2 to 87.7
87.7 to 86.2
86.2 to 84.7
84.7 to 83.2
Layer Thickness
(m)
2.3
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
Estimated k
(m/day)
0.000864 to
0.00000864
0.000864 to
0.00000864
0.000864 to
0.00000864
0.000864 to
0.00000864
0.864 to
0.000864
> 0.864
0.000864 to
0.00000864
> 0.864
0.000864 to
0.00000864
Table App27.  Wolf/SR 57 Hydraulic Conductivity B-1
Boring (B-1)
Drilling Elevation 103.2 m
Boring Bottom
Elev. 80.2 m
Riverbed Elev. 103 m
Ground Water
Elev. N/A
Soil Type
Silt
Sand

Sand
Silt
Sand
Sand
Silt
Sand
Description
wet, moist, brown,
clayey and sand
wet, brown, slightly
silty wood at tip of
spoon
wet, brown, coarse,
quartzite pebbles
wet, gray, sandy
wet, brown, fine
coarse, silty
wet, brown, grayish-
white, sandy
wet, gray, fine grain
Boring St. 5+68
River Center St. 5+69


Boring Distance 1 m
Elevation Range (m)
103.2 to 101.4
101.4 to 99.9

99.9 to 98.4
98.4 to 97.2
97.2 to 95.4
95.4 to 93.9
93.9 to 89.3
89.3 to 80.2
Layer Thickness
(m)
1.8
1.5

1.5
1.2
1.8
1.5
4.6
9.1
Estimated k
(m/day)
0.864 to
0.000864
> 0.864

> 0.864
0.864 to
0.000864
> 0.864
> 0.864
0.864 to
0.000864
> 0.864
Calculated k
(m/day)
1.03









-------
Table App28.  Wolf/SR 57 Hydraulic Conductivity B-2
Boring (B-2)
Drilling Elevation 104 m
Boring Bottom 82 2 m
Riverbed Elev. 103 m
Ground Water Elev. N/A
Soil Type
Silt
Silt
Sand
Sand
Sand
Silt
Sand
Description
wet, moist, brown,
moderately clayey
and sandy
wet, very soft, gray
wet, brown, very
coarse
coarse to fine
wet, light gray, silty
stiff, gray
wet, gray/rust, fine
Boring St. 4+58
River Center St. 5+69
Boring Distance 111m
Elevation Range (m)
104.0 to 102.2
102.2 to 100.7
100.7 to 98.0
98.0 to 94.5
94.5 to 91.6
91.6 to 85.7
85.7 to 82.2
Layer
Thickness (m)
1.8
1.5
2.7
3.5
2.9
5.9
3.5
Estimated k
(m/day)
0.864 to
0.000864
0.864 to
0.000864
> 0.864
> 0.865
> 0.866
0.0864 to
0.000864
> 0.864
Calculated k
(m/day)
1.08






Table App29.  Wolf/SR 57 Hydraulic Conductivity B-3
Boring (B-3)
Drilling Elevation 106.3 m
Boring Bottom 84 7 m
Riverbed Elev. 103 m
Ground Water M/A
Elev. N/A
Soil Type
Silt
Silt
Silt
Silt
Sand
Sand
Sand
Sand
Silt
Sand
Description
moist, brown/gray,
sandy
gray
gray, clayey, sand
seams
wet, gray, sandy
wet, light brown,
coarse
wet, light brown/
gray, coarse to fine
coarse
fine
wet, rust colored,
sandy
wet, gray,
fine-grained
Boring St. 8+68
River Center St. 5+69
Boring Distance 299 m
Elevation Range (m)
106.3 to 104.5
104.5 to 103.0
103.0 to 101.5
101.5 to 98.4
98.4 to 96.9
96.9 to 95.4
95.4 to 92.3
92.3 to 90.8
90.8 to 87.7
87.7 to 84.7
Layer
Thickness
(m)
1.8
1.5
1.5
3.1
1.5
1.5
3.1
1.5
3.1
3
Estimated k
(m/day)
0.864 to
0.000864
0.864 to
0.000864
0.864 to
0.000864
0.864 to
0.000864
> 0.864
> 0.864
> 0.864
> 0.864
0.864 to
0.000864
> 0.864
Calculated k
(m/day)

1.07
1.09








-------
Table App30.  Wolf/McKinstry Hydraulic Conductivity B-1
Boring (B-1)
Drilling Elevation 104.5 m
Boring Bottom Q1 A m
Riverbed Elev. 101 m
Ground Water M/A
Elev. N/A
Soil Type
Clay
Clay
Sand
Sand
Sand
Sand
Description
brown, silty
gray, silty
gray, silty,
fine-grained
fine to medium-
grained, silty, gray
fine to medium-
grained, silty, gray,
with some small
gravel
fine to medium-
grained, white, silty
Boring St. 4+935
River Center St. 4+967
Boring Distance 32 m
Elevation Range (m)
104.5 to 102.7
102.7 to 99.6
99.6 to 97.3
97.3 to 93.5
93.5 to 90.5
90.5 to 87.4
Layer Thickness
(m)
1.83
3.05
2.28
3.81
3.05
3.05
Estimated k
(m/day)
0.000864 to
0.00000864
0.000864 to
0.00000864
> 0.864
> 0.864
> 0.864
> 0.864
Calculated k
(m/day)

1.09




Table App31.  Wolf/McKinstry Hydraulic Conductivity B-2
Boring (B-2)
Drilling irusm
Elevation 104.5m
Boring Bottom 84 4 m
Riverbed Elev. 101 m
Ground Water M/A
Elev. N/A
Soil Type
Clay
Clay
Sand
Sand
Sand
Sand
Sand
Sand
Sand
Description
brown, silty
gray, silty
fine-grained, gray, silty
fine to medium-grained,
silty gray
fine to medium-grained,
silty gray, with gravel
fine to medium-grained,
silty, reddish-brown
fine to medium-grained,
silty, reddish-brown, with
some small gravel
fine-grained, silty,
reddish-brown
fine-grained, silty, gray
Boring St. 5+010
River Center St. 4+967
Boring Distance 43 m
Elevation Range (m)
104.5 to 102.7
102.7 to 101.2
101.2 to 98.1
98.1 to 96.6
96.6 to 95.1
95.1 to 93.5
93.5 to 89.0
89.0 to 87.5
87.5 to 84.4
Layer
Thickness (m)
1.83
1.52
3.05
1.52
1.52
1.52
4.57
1.52
3.05
Estimated
k (m/day)
0.000864 to
0.00000864
0.000864 to
0.00000864
> 0.864
> 0.864
> 0.864
> 0.864
> 0.864
> 0.864
> 0.864
Calculated
k (m/day)


2.93







-------
Table App32.  Wolf/SR 76 Hydraulic Conductivity B-1
Boring (B-1)
Son
Boring Bottom 84 5 m
Riverbed Elev. 102.3 m
Ground Water „„ .
Elev. yb'4 m
Soil Type
Clay
Silt
Clay
Sand
Sand
Sand
Clay
Sand
Sand
Sand
Description
Silty
trace wood
pieces
lean, sandy

with silt

lean
with silt

Silty
Boring St. 3+722
River Center St. 3+688
Boring Distance 34 m
Elevation Range (m)
106.0 to 104.0
104.0 to 102.2
102.2 to 99.1
99.1 to 96.1
96.1 to 94.6
94.6 to 93.0
93.0 to 91.5
91.5 to 87.0
87.0 to 85.4
85.4 to 84.5
Layer Thickness
(m)
1.98
1.83
3.05
3.05
1.52
1.53
1.52
4.57
1.52
0.94
Estimated k
(m/day)
0.000864 to
0.00000864
0.864 to 0.000864
0.000864 to
0.00000864
> 0.864
> 0.864
> 0.864
0.000864 to
0.00000864
> 0.864
> 0.864
> 0.864
Calculated k
(m/day)

N/A








Table App33.  Wolf/SR 76 Hydraulic Conductivity B-2
Boring (B-2)
Drilling Elevation 106 m
Boring Bottom Elev. 84.5 m
Riverbed Elev. 102.3 m
Ground Water Elev. 99.9 m
Soil Type
Gravel
Sand
Clay
Sand
Sand
Sand
Sand
Sand
Sand
Sand
Sand
Description
with sand
with gravel
lean
Clayey
Silty

with silt

with silt
Clayey
with silt
Boring St. 3+660
River Center St. 3+688
Boring Distance 28 m
Elevation Range (m)
106.0 to 104.0
104.0 to 102.2
102.2 to 100.7
100.7 to 99.2
99.2 to 97.6
97.6 to 96.1
96.1 to 94.6
94.6 to 91.5
91.5 to 87.0
87.0 to 85.5
85.5 to 84.5
Layer Thickness
(m)
1.98
1.83
1.52
1.52
1.52
1.52
1.52
3.05
4.57
1.52
0.91
Estimated k
(m/day)
> 8.64
> 0.864
0.000864 to
0.00000864
> 0.864
> 0.864
> 0.864
> 0.864
> 0.864
> 0.864
> 0.864
> 0.864
Calculated
k
(m/day)



N/A








-------

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United States
Environmental Protection
Agency
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Office of Research and Development (8101R)
Washington, DC 20460

Official  Business
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