HYDROGEOLOGIC CHARACTERIZATION
AND GROUNDWATER SOURCE
DEVELOPMENT ASSESSMENT
FOR BUTLER COUNTY
Draft Subject to Revision
GEOLOGICAL SURVEY OF ALABAMA
Berry H. (Nick) Tew, Jr.
State Geologist
HYDROGEOLOGIC CHARACTERIZATION AND
GROUNDWATER SOURCE DEVELOPMENT ASSESSMENT
FOR BUTLER COUNTY
OPEN-FILE REPORT __
By
Marlon R. Cook,
Ralph R. Norman,
and
Gheorghe M. L. Ponta
Full funding for this project was provided by the Geological Survey of Alabama as part of the
GSA Statewide Groundwater Assessment.
Tuscaloosa, Alabama
2014
CONTENTS
Introduction ...............................................................................................................................
Acknowledgments.....................................................................................................................
Physiography and topography...................................................................................................
Hydrogeology ...........................................................................................................................
Lower Cretaceous undifferentiated .....................................................................................
Tuscaloosa Group ...............................................................................................................
Coker Formation ...........................................................................................................
Gordo Formation ...........................................................................................................
Eutaw Formation ...........................................................................................................
Selma Group .......................................................................................................................
Mooreville and Demopolis Chalks ...............................................................................
Ripley Formation ..........................................................................................................
Cusseta Sand Member.............................................................................................
Unnamed Upper Member .......................................................................................
Prairie Bluff Chalk ........................................................................................................
Providence Sand............................................................................................................
Midway Group ....................................................................................................................
Clayton Formation ........................................................................................................
Porters Creek Formation ...............................................................................................
Neheola Formation........................................................................................................
Wilcox Group......................................................................................................................
Salt Mountain Limestone ..............................................................................................
Nanafalia Formation .....................................................................................................
Tuscahoma Sand ...........................................................................................................
Hatchetigbee Formation ................................................................................................
Claiborne Group..................................................................................................................
Tallahatta Formation .....................................................................................................
Lisbon Formation ..........................................................................................................
Hydrogeologic assessment methodology............................................................................
Well depth .....................................................................................................................
Depth to water ...............................................................................................................
Pumping rates................................................................................................................
Specific capacity ...........................................................................................................
Net potential productive intervals .................................................................................
Potentiometric surfaces and groundwater level impacts ...............................................
Hydrographs and aquifer decline curves.......................................................................
Hydrogeologic assessment ..................................................................................................
Ripley aquifer................................................................................................................
Well depth ...............................................................................................................
Depth to water .........................................................................................................
Pumping rates..........................................................................................................
Specific capacity .....................................................................................................
Net potential productive intervals and downgradient limit of fresh water .............
Potentiometric surfaces and groundwater level impacts .........................................
Page
1
1
2
2
3
5
5
6
8
9
9
9
9
10
10
11
11
11
12
12
12
13
13
13
14
14
14
15
15
16
16
16
17
18
19
20
21
21
22
22
22
22
22
23
i
Pre-1961 static groundwater levels ...................................................................
Pre-1996 static groundwater levels ...................................................................
Current static groundwater levels .....................................................................
Hydrographs and aquifer decline curves.................................................................
Clayton aquifer..............................................................................................................
Well depth ...............................................................................................................
Depth to water .........................................................................................................
Pumping rates..........................................................................................................
Specific capacity .....................................................................................................
Net potential productive intervals and downgradient limit of fresh water .............
Potentiometric surfaces and groundwater level impacts .........................................
Hydrographs and aquifer decline curves.................................................................
Well capture zones ..............................................................................................................
Groundwater exploration and additional groundwater source development ......................
Conclusions and recommendations...........................................................................................
References cited ........................................................................................................................
23
23
24
24
26
28
28
28
29
29
29
30
31
31
34
38
ILLUSTRATIONS
FIGURES
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Butler County hydrogeologic assessment area in south-central Alabama ...........
Physiographic regions for Alabama including the Butler County
hydrogeologic assessment ....................................................................................
Generalized stratigraphy for Butler County.........................................................
Basement faulting and chloride concentrations in water from the Tuscaloosa
Group aquifer .......................................................................................................
Diagram depicting drawdown and potentiometric surfaces prior to and after
pumping in a confined aquifer .............................................................................
Hydrograph showing long-term water levels in Greenville well no. 1 ................
Hydrograph showing long-term water levels in Greenville well no. 2 ................
Hydrograph showing long-term water levels in Greenville well no. 3 ................
Hydrograph showing long-term water levels in Greenville well no. 4 ................
Hydrograph showing long-term water levels in Greenville well no. 5 ................
Hydrograph showing long-term water levels in Clayton aquifer well K-2 .........
Page
2
3
4
7
19
25
26
27
27
28
30
PLATES
Plate 1.
Plate 2.
Plate 3.
Plate 4.
Assessment area and digital elevation model for the Butler County hydrogeologic
assessment
Geology for the Butler County hydrogeologic assessment area
Hydrogeologic cross section B-B’, Lowndes, Butler, and Covington Counties,
Alabama
Hydrogeologic cross section C-C’, Wilcox, Butler, and Crenshaw Counties,
Alabama
ii
Plate 5.
Plate 6.
Plate 7.
Plate 8.
Plate 9.
Plate 10.
Plate 11.
Plate 12.
Plate 13.
Plate 14.
Plate 15.
Plate 16.
Plate 17.
Plate 18.
Plate 19.
Geologic structure for the top of the Ripley Formation, Butler County
hydrogeologic assessment area
Geologic structure for the top of the Clayton Formation, Butler County
hydrogeologic assessment area
Depth to water for the Ripley aquifer
Normalized pumping rates for the Ripley aquifer
Normalized specific capacities for the Ripley aquifer
Net potential productive intervals for the Ripley aquifer in the Butler County
hydrogeologic assessment area
Pre-1961 potentiometric surface for the Ripley aquifer
Pre-1996 potentiometric surface for the Ripley aquifer
Current potentiometric surface for the Ripley aquifer
Depth to water for the Clayton aquifer
Normalized pumping rates for the Clayton aquifer
Normalized specific capacities for the Clayton aquifer
Net potential productive intervals for the Clayton aquifer in the Butler County
hydrogeologic assessment area
Historic potentiometric surface for the Clayton aquifer
Current potentiometric surface for the Clayton aquifer
iii
INTRODUCTION
All public-water supplies in Butler County are produced from groundwater sources. Due
to increasing population and water demands and significant water level declines in the Ripley
aquifer, the Butler County Water Authority and Greenville water Works & Sewer Board joined
to form the Butler County Water Cooperative (BCWC) to maximize resources to develop future
water sources. The first joint water source development venture was a test well in northeast
Butler County to test the potential of the deep Gordo aquifer. This well was unsuccessful but
provided valuable scientific data for future ventures. More recently, the coop requested the
Geological Survey of Alabama (GSA) to conduct a comprehensive county-wide hydrogeologic
assessment to characterize subsurface hydrogeologic conditions and to identify future viable
groundwater sources.
The purpose of the project was to generate data that can be used by the BCWC to make
informed decisions related to development of new groundwater sources in the County. These
data will be used by GSA to better understand the hydrogeology of Butler County south-central
Alabama, as part of the statewide groundwater assessment being conducted by GSA. Data from
oil and gas and water wells provide opportunities to see into the subsurface to evaluate
groundwater quantity and quality characteristics that can be used to develop and protect
groundwater sources. Data from oil and gas test wells and numerous water wells were evaluated
during this investigation (plate 1). Hydrogeologic, geochemical, and land-use data were used to
evaluate groundwater recharge, movement, aquifer storage, and the potential for developing
additional groundwater sources from Cretaceous aquifers in the BCWC service area.
ACKNOWLEDGMENTS
The Geological Survey of Alabama acknowledges those individuals whose participation
and cooperation made this study possible. BCWC president, Judge Steve Norman; Mayor Dexter
McClendon; Representative Charles Newton; Mr. Chris Finley, Manager, Greenville Water
Works and Sewer Board; Mr. Wesley Bass, Butler County Manager, Artesian Utilities; Mr.
Bobby Hood Jr., Manager Fort Deposit Water and Sewer Board; Mr. Kenneth Blackburn,
Manager, Georgiana Water Works and Sewer Board; and Mr. Josh Pierce, Goodwyn, Mills, and
Cawood were instrumental in providing assistance for the completion of this research.
1
PHYSIOGRAPHY AND TOPOGRAPHY
The area of investigation covers about 3,000 square miles (mi2) in south-central Alabama
and includes Butler and parts of Crenshaw, Lowndes, Wilcox, Monroe, Conecuh, and Covington
Counties and the cities of Greenville and Georgiana (fig. 1 and plate 1). The investigation area
lies primarily in the Southern Red Hills district of the East Gulf Coastal Plain physiographic
section. The Southern Red Hills are classified as southward-sloping uplands of moderate relief
(fig. 2).
HYDROGEOLOGY
The geology of the area of investigation is composed of coastal plain sediments overlying
piedmont crystalline rocks. Coastal plain sediments vary in age from lower Cretaceous to middle
Eocene (fig. 3 and plate 2) and are composed of interbedded sand, clay, and limestone that dip
south-southwestward at about 30 to 40 feet per mile (ft/mi) (plate 3). These sediments thicken
southwestward toward the center of the Gulf of Mexico basin from about 2,500 ft in central
Lowndes County to more than 8,000 ft in northern Covington County (plate 3).
Figure 1.—Butler County hydrogeologic assessment area in south-central Alabama.
2
Figure 2.—Physiographic regions for Alabama including the Butler County
hydrogeologic assessment.
LOWER CRETACEOUS UNDIFFERENTIATED
Lower Cretaceous sediments overlie metamorphic and igneous crystalline rocks in the
Bullock County area. Pink nodular limestone fragments and red and green clay near the top of
the unit distinguish it from the massive sands of the overlying Late Cretaceous Coker Formation
of the Tuscaloosa Group (Davis, 1987). The total thickness of Lower Cretaceous sediments is
known to reach more than 7,000 ft in Mobile Bay (Maher and Applin, 1968). Sediments of Early
3
Figure 3.— Generalized stratigraphy for Butler County.
Cretaceous age do not crop out in Alabama, but thin northward and pinch out in the subsurface
south of the Fall Line. The total thickness of Lower Cretaceous sediments was not penetrated in
wells drilled in the assessment area. Descriptions of drill cuttings by Alabama State Oil and Gas
Board personnel indicate that Lower Cretaceous sediments are composed of alternating sand,
gravel and clay layers. Sands are described as medium to very coarse grained with abundant
gravel, large pink feldspar crystals, and pink nodular limestone fragments. Clays are purple, red,
brown, and green and are micaceous.
There is currently no water production from the Lower Cretaceous in Alabama. However,
due to shallower formations with water containing chlorides above drinking water standards, it is
unlikely that the Lower Cretaceous would be suitable as a potable water source.
4
TUSCALOOSA GROUP
COKER FORMATION
The Coker Formation typically composes the lower part of the Tuscaloosa Group in most
of Alabama. Smith (2001) recognized a threefold subdivision of Tuscaloosa sediments in
southeast Alabama that included the lower Tuscaloosa Coker Formation and overlying upper
Tuscaloosa Gordo Formation separated by the “middle marine shale.” This well-defined
stratigraphic separation was observed throughout the Butler County assessment area in oil and
gas exploratory wells and was adopted for this research. Smith (2001) stated that the maximum
thickness of the Coker Formation in southeast Alabama is about 400 to 450 ft. Descriptions of
drill cuttings from the Gulf Refining Company K. Hooks #1 (Alabama Oil and Gas Board permit
number (OGB #) 308) well in southwest Butler County combined with geophysical log
correlations indicate that the top of the Coker Formation was encountered at a depth of about
3,617 ft (-3,253 ft MSL) and the unit is about 274 ft thick. In central Lowndes County the Coker
Formation was encountered in the C. S. Wright #1 oil and gas test well (OGB #517) at a depth of
1,600 ft (-1,400) and was about 300 ft thick and has a dip rate of about 50 ft/mi, which compares
to the rate of dip documented by Smith (2001) of about 42 ft/mi in southeast Alabama and about
59 ft/mi documented by Cook and others (2013) in Bullock County.
Smith (2001) described Coker sediments as light-gray to reddish-orange, ferruginousstained, poorly sorted, invariably etched sand with trace amounts of coarse muscovite mica,
igneous and/or metamorphic rock fragments, and coarse grains of orthoclase feldspar with grain
size from fine to very coarse (0.03 to 2.0 millimeters (mm)), and gravel that is generally palepink to grayish-orange, usually somewhat rounded, and granular (2 to 4 mm) to rarely pebble (4
to 32 mm) in size. Interbedded clays are finely muscovitic, noncalcareous, silty, and varicolored
yellow, orange, red and purple. The formation is described by Alabama Oil and Gas Board
personnel from Butler County well cuttings as alternating sand and shale layers. Sands are
medium to coarse-grained and micaceous. Shales are dark gray, micaceous, and carbonaceous.
The Coker Formation is a minor aquifer in southeast Alabama and due to excessive chlorides,
has no potential for economic fresh-water production in Butler County.
“MIDDLE MARINE SHALE”
The “middle marine shale” is an informal name for a relatively thin yet persistent clay or
shale that occurs throughout Alabama (Smith, 2001). Although the unit is not recognized at the
5
surface and has no significance as an aquifer, it is useful in determining the top of the Coker
Formation and base of the overlying Gordo Formation for data correlation and drilling. The unit
consists of medium-gray to olive-gray, massive-bedded to thinly laminated, finely muscovitic
and lignitic, quartzose silty clay and shale, which in part is moderately calcareous and contains
common to abundant thin-walled pelecypod shell fragments (Smith, 2001). The unit was
encountered in the Gulf Refining Company K. Hooks #1 (OGB #308) well in southwest Butler
County at a depth of 3,492 ft (-3,128 ft MSL) and is about 125 feet thick. Drill cuttings from the
unit in the Hooks #1 well was described as shale, gray, greenish, and black, micaceous, and
carbonaceous. The unit was encountered in the C. S. Wright #1 well (OGB #517) in central
Lowndes County at a depth of 1,525 ft (-1,325 ft MSL) and is about 75 ft thick.
GORDO FORMATION
The Gordo Formation is the upper unit of the Tuscaloosa Group and is well defined from
drill cuttings and geophysical log character where is occurs throughout Alabama. The base of the
unit is defined as the contact with the “middle marine shale.” The upper contact with the Eutaw
Formation is mainly defined by sediment color and relatively massive clay layers in the upper
part of the Gordo, related to the different environments of deposition of the two units. The origin
of the Eutaw Formation is primarily marginal marine whereas the Gordo originates from fluvial
deposition (Cook, 1993). The basal Eutaw is composed of a regionally persistent massive sand
layer with marine material including shell fragments, aragonite, and glauconite and colors from
gray to buff. The top of the Gordo is nonfossiliferous and is characterized by relatively massive,
varicolored (orange, brown, red, pink, and purple) clays, coarse-grained sand, and gravel. The
Gordo Formation was encountered in the Gulf Refining Company K. Hooks #1 well (OGB #308)
in southwest Butler County at a depth of 3,002 ft (-2,638 ft MSL) where it is 490 feet thick (plate
3). In contrast, the updip Gordo in central Lowndes County in the C. S. Wright #1 well (OGB
#517) was penetrated at 960 ft (-760 ft MSL) and was about 560 ft thick. Smith (2001) reported
that the dip of the Gordo Formation in Coffee, Dale, and Henry Counties is to the southsouthwest at about 35 ft/mi. In the Butler County area, the Gordo dips south-southwest at about
50 ft/mi (plate 3). The Gordo Formation is the primary aquifer for Bullock, Barbour, and Pike
Counties in southeast Alabama and Montgomery, Elmore, Autauga, and Lowndes Counties in
the central part of the state. Although individual water-producing sands are relatively thin, the
accumulated contribution from the entire formation yields adequate quantities of excellent
6
quality water. Influxes of deep mineralized water into Cretaceous aquifers (including the Gordo
aquifer) along the Alexander City, Towaliga, and Bartletts Ferry Faults that underlie the coastal
plain in central Alabama have profoundly influenced groundwater quality in southwest
Montgomery, southern Lowndes, and Butler Counties (Cook, 2002) (fig. 4).
Figure 4.—Basement faulting and chloride concentrations in water from
the Tuscaloosa Group aquifer.
7
EUTAW FORMATION
The Eutaw Formation extends from west and central Alabama, where it is about 350 to
400 ft thick, to eastern Alabama where the formation thins to less than 300 ft. The formation
outcrops about 25 miles north of the assessment area in southern Autauga County. The Eutaw
Formation was encountered in the Gulf Refining Company K. Hooks #1 well (OGB #308) in
southwest Butler County at a depth of 2,730 ft (-2,366 ft MSL) where it is 262 feet thick (plate
3). In contrast, the Eutaw in central Lowndes County in the C. S. Wright #1 well (OGB #517)
was penetrated at 650 ft (-450 ft MSL) and was about 320 ft thick. (plate 4).
Smith (2001) described the subsurface Eutaw in Bullock, Pike, and Barbour Counties as
very fine quartzose sandy clay and calcareous shale containing traces of glauconite and
phosphatic grains with very rare pelecypod shell fragments. Clays and shales are interbedded
with lenses and thin beds of indurated very fine- to fine-grained quartzose sandstone, sandy
limestone, and thin beds of sand. The Eutaw is described from drill cuttings from the Gulf
Refining Company K. Hooks #1 well (OGB #308) in southwest Butler County as gray, fine- to
medium-grained, micaceous and glauconitic sand with interbedded gray micaceous shale. Drill
cuttings from the C. S. Wright #1 well (OGB #517) in central Lowndes County were described
as medium- to coarse-grained glauconitic sand with abundant phosphatic material and bone
fragments. Cook (1993) stated that excessive concentrations of fluoride in water from the Eutaw
aquifer in eastern Lowndes and western Montgomery Counties was derived from phosphatic and
skeletal fish material in the Eutaw sediments.
The Eutaw Formation in west and central Alabama can be divided into three distinctive
lithologic layers: the lower basal sand unit, the middle Eutaw unit, and the upper Tombigbee
Sand member (Cook, 1993). The basal sand unit is persistent and is recognized in geophysical
log character across the state. Geophysical log character and net sand mapping suggests that the
basal sand unit was deposited as a barrier island complex that extended from northeast
Mississippi across much of Alabama (Cook, 1993). The basal sand supplies water for public
water supplies throughout west and central Alabama and is a target for water well drilling where
chlorides or fluoride is not excessive.
8
SELMA GROUP
The Selma Group is upper Cretaceous in age and includes the Mooreville Chalk,
Demopolis Chalk, Ripley Formation, Providence Sand, and Prairie Bluff Chalk in south-central
Alabama.
MOOREVILLE AND DEMOPOLIS CHALKS
The Mooreville Chalk is a yellowish-gray to dark-bluish-gray clayey compact
fossiliferous chalk and chalky marl. The upper part of the formation is composed of the Arcola
Limestone Member, which includes two to four beds of light-gray dense, brittle fossiliferous
limestone about 10 ft thick (Raymond and others, 1988). Thickness ranges from 270 ft in west
Alabama to more than 800 ft in the central part of the state. The Mooreville Chalk was
penetrated in the Gulf Refining Company K. Hooks #1 well (OGB #308) in southwest Butler
County at a depth of 1,920 ft (-1,556 ft MSL) where it was 810 ft thick (plate 3).
The Demopolis Chalk is a light-gray to medium-light-gray fossiliferous chalk. The lower
part of the formation consists of thin beds of marly chalk. Thickness ranges from 495 ft in
Sumter County to about 500 ft in central Alabama. It was penetrated in the Gulf Refining
Company K. Hooks #1 well (OGB #308) in southwest Butler County at a depth of 1,420 ft (1,056 ft MSL) where it was 500 ft thick (plate 3).
RIPLEY FORMATION
CUSSETA SAND MEMBER
The basal part of the Ripley Formation in east and central Alabama is designated as the
Cusseta Sand Member. Outcrop exposures of the Cusseta Sand Member in Alabama extend from
the Chattahoochee River in northeastern Barbour County and southeastern Russell County
westward through Central Bullock County into southern Montgomery County (Smith, 2001). In
outcrop, the Cusseta consists predominantly of cross-bedded coarse quartzose sand and granular
gravel with subordinate beds of dark-gray to black carbonaceous clay (Smith, 2001). The
Cusseta surface exposure (recharge area) in Bullock County varies from 5 to 10 miles wide from
the Barbour County line westward to Union Springs and thins to less than 2 miles wide into
Montgomery County (plate 2). Along the Chattahoochee River, the Cusseta averages about 200
ft in thickness. Westward, the Cusseta gradually thins to about 125 ft in eastern and central
Montgomery County and merges with the Demopolis Chalk in south-central Montgomery
County. Plate 4 shows the Cusseta Member extending westward in the subsurface, pinching out
east of Greenville in northeastern Butler County. However, farther west across Butler County,
9
the basal Ripley Formation is dominated by medium to coarse-grained sand and could actually
be a westward extension of the Cusseta Member. The Cusseta Member was identified by Smith
(2009) in the Butler County Water Supply District Test Well #1 in northeast Butler County
where it was penetrated at a depth of 372 ft (-12 ft MSL) and was 187 ft thick. Smith described
the unit as poorly sorted fine- to coarse-grained sand, micaceous and glauconitic. The Cusseta
Sand Member is historically a major water producer in northern Dale and southern Pike
Counties.
UNNAMED UPPER MEMBER
The unnamed upper member of the Ripley Formation extends in outcrop across the entire
state of Alabama with the upgradient terminus extending across southern Montgomery,
Lowndes, and Dallas Counties in the central part of the state (plate 2). Smith (2001) described
the surface exposed Ripley as massive-bedded to cross-bedded, glauconitic fine sands and sandy
clay with thin indurated beds of fossiliferous sandstone having a total thickness of about 135
feet. Smith (2001) stated that the unnamed upper member of the Ripley Formation consists of
predominantly fine-grained lithologies and serves as an aquiclude. The Ripley Formation was
penetrated in the Gulf Refining Company K. Hooks #1 well (OGB #308) in southwest Butler
County at a depth of 1,146 ft (-782 ft MSL) and was 274 ft thick and was described as
fossiliferous, very coarse-grained sand (plate 3). It was penetrated in the Butler County Water
Supply District Test Well #1 in northeast Butler County at a depth of 290 ft (70 ft MSL) and was
97 ft thick. Plate 5 shows that the Ripley Formation dips south-southwest at about 27 ft/mi
through Butler County and increases to about 33 ft/mi in Covington and Conecuh Counties. The
Ripley Formation is the sole source of public water supplies for much of Butler County.
PRAIRIE BLUFF CHALK
The Prairie Bluff Chalk is a bluish-gray firm sandy, fossiliferous, brittle chalk that crops
out from Sumter County to south-central Bullock County where it grades into the Providence
Sand (Raymond and others, 1988). It reaches a maximum outcrop thickness of 110 ft in Lowndes
County (Raymond and others, 1988) and thickens downgradient before it grades into the
Providence Sand at depth in Butler County (plate 3). Although locally absent, it serves as an
aquiclude in central and western Butler County.
10
PROVIDENCE SAND
The Providence Sand is the uppermost unit within the Cretaceous System in eastern
Alabama. In outcrop, the Providence extends from the Georgia state line through northern
Barbour, southern Bullock and Montgomery Counties and terminates in southeastern Lowndes
County (Szabo and others, 1988) (plate 2). It was penetrated in the Gulf Refining Company K.
Hooks #1 well (OGB #308) well in southwest Butler County at a depth of 1,010 ft (-646 ft MSL)
and was 130 ft thick. The Providence Sand is a minor aquifer in southeast Alabama and serves an
aquiclude in Butler County, composed of fossiliferous chalk and chalky shale. Therefore it is not
a target for water well drilling in Butler County.
MIDWAY GROUP
The Midway Group is lower Tertiary in age and includes the Clayton Formation, Porters
Creek Formation, and the Naheola Formation in south-central Alabama.
CLAYTON FORMATION
The oldest Tertiary sediments in Alabama rest unconformably upon sediments assignable
to the Upper Cretaceous Providence Sand (Smith, 2001). In Alabama, these beds are assigned to
the Clayton Formation, which is named from typical exposures near the town of Clayton in westcentral Barbour County (Langdon, 1891). In outcrop, the Clayton Formation extends from the
Georgia state line in southeastern Barbour County westward to east-central Marengo County in
west-central Alabama. The outcrop, or recharge area in the Butler County hydrogeologic
assessment area trends northwestward from northwestern Crenshaw, through extreme
northeastern Butler, southwestern Lowndes, and into northern Wilcox Counties (plate 2). The
Clayton Formation dips south-southwest at a rate of about 33 ft/mi in the hydrogeologic
assessment area (plate 6). It consists of a geographically widespread basal transgressive sand
composed of 5 to 10 ft of gravelly medium to coarse quartzose sand and clay pebbles. The
overlying beds generally consist of 10 to 25 ft of highly fossiliferous sandy limestone, usually
represented by deeply weathered exposures of ferruginous sand containing chert fragments
(Smith, 2001). This limestone is normally overlain by massive-bedded silty clay and clayey very
fine sand. In many exposures, the top of the formation is marked by a very glauconitic clayey
sand, which is usually deeply weathered, resulting in reddish or reddish-brown residual
ferruginous sandy clay containing thin lenses and seams of the dehydrated iron oxide goethite,
commonly known as brown iron ore (Smith, 2001).
11
The Clayton Formation was penetrated in the Gulf Refining Company K. Hooks #1 well
(OGB #308) well in southwest Butler County at a depth of 842 ft (-478 ft MSL) and was 130 ft
thick. Drill cuttings from the Clayton in this well were described as hard gray limestone and clay
at the top and about 90 ft of coarse-grained sand and sandy lime at the base. The Clayton
Formation is a major source of water supplies in southeast Alabama, but has a limited number of
wells in the Butler County hydrogeologic assessment area and is considered a minor aquifer.
However, depending on water quality, the Clayton Formation should be considered as a target
for future water supply development.
PORTERS CREEK FORMATION
The Porters Creek Formation in outcrop extends from Sumter County in west-central
Alabama to southwester Pike County in the southeast part of the state (Szabo and others, 1988).
It consists of dark-brown to black massive marine clay at the base and brownish-gray calcareous,
glauconitic, shelly, silty Clay at the top. The unit becomes increasingly calcareous eastward
where a prominent limestone occurs in the middle of the formation and the upper part grades into
calcareous, micaceous silt and fine-grained sand (Raymond and others, 1988). The Porters Creek
Formation was penetrated in the Gulf Refining Company K. Hooks #1 well (OGB #308) well in
southwest Butler County at a depth of 730 ft (-366 ft MSL) and was 120 ft thick. The Porters
Creek Formation in the Butler County hydrogeologic assessment area serves as an aquiclude.
NAHEOLA FORMATION
The Naheola Formation is identified in outcrop from Sumter County in west-central
Alabama to northwest Butler County (Szabo and others, 1988). The unit is divided into the Oak
Hill Member at the base and Coal Bluff Marl Member at the top. The Oak Hill Member consists
of brownish-gray laminated sandy silt and silty clay and beds of greenish-gray fine-grained sand.
Lignite, 1 to 7 ft thick, is present locally at the top of the member. The Coal Bluff Marl Member
consists of glauconitic partly fossiliferous sand and fossiliferous sandy marl and contains thinbedded silty clay in the upper part. The Naheola Formation was not identified in the subsurface
in Butler County.
WILCOX GROUP
The Wilcox Group is lower Tertiary in age and includes the Salt Mountain Limestone,
Nanafalia Formation, and the Tuscahoma Sand in south-central Alabama.
12
SALT MOUNTAIN LIMESTONE
Although most likely hydraulically connected to the underlying Clayton Formation, the
Salt Mountain Limestone is considered as a separate hydrogeologic unit due to its distinctive
lithologic character of fossiliferous limestone with quartz sand interbeds (Smith, 2001). The
presence locally in the study area of clay beds occurring between the Clayton Formation and the
overlying Salt Mountain Limestone, assigned to the Porters Creek Formation by Smith (2001),
indicates local hydraulic separation of the two units in the Butler County hydrogeologic
assessment area.
The Salt Mountain in southeast Alabama is a major aquifer composed of porous and
permeable limestone. Westward, the unit is more clastic and is described in the Gulf Refining
Company K. Hooks #1 well (OGB #308) well in southwest Butler County as sand, very
glauconitic and light gray hard limestone. The Salt Mountain Limestone was penetrated in the K.
Hooks #1 well at 580 ft (-216 ft MSL) and was 150 ft thick. The Salt Mountain Limestone is not
considered as a target for water source development in Butler County.
NANAFALIA FORMATION
The Nanafalia Formation crops out from southern Barbour in southeast Alabama,
westward through central Crenshaw and Butler Counties in the south-central part of the state,
and continues into east Mississippi in southern Sumter County. It consists of massive crossbedded sand and glauconitic and fossiliferous fine sands (Smith, 2001). The recharge area in
Butler County is about 8 miles wide, on average (Szabo and others, 1988). The Nanafalia
Formation in the subsurface consists of greenish-colored and glauconitic-stained coarse to very
coarse quartzose sand, fragments of marine fossils, and abundant medium to coarse glauconite.
Some usually dense, indurated, frequently sandy limestone beds occur. (Smith, 2001). The
Nanafalia Formation was penetrated in the Gulf Refining Company K. Hooks #1 well (OGB
#308) well in southwest Butler County at a depth of 500 ft (-136 ft MSL) and was 80 ft thick.
Although the Nanafalia Formation is present in the southern two-thirds of Butler County it is not
considered as a target for public water supply source development but may be accessed for
domestic or agricultural supplies.
TUSCAHOMA SAND
The Tuscahoma Sand crops out from northern Henry County in southeast Alabama,
through southern Crenshaw and Butler Counties in south-central Alabama, to northern Choctaw
13
County in the southwest part of the state. Its thickness in outcrop varies from about 90 ft in
Henry County to 350 ft in Choctaw County. The Tuscahoma Sand was penetrated in the Gulf
Refining Company K. Hooks #1 well (OGB #308) well in southwest Butler County at a depth of
380 ft (-16 ft MSL) and was 120 ft thick. It was described by Smith (2001) as predominantly
fine-grained clay/shale lithologies in southeast Alabama and serves as an aquiclude throughout
the southeast and south-central parts of the state.
HATCHETIGBEE FORMATION
The Hatchetigbee Formation crops out from central Henry County in southeast Alabama,
through extreme southern Crenshaw and Butler Counties in south-central Alabama, to central
Choctaw County in the southwest part of the state. Its thickness varies from about 35 ft in
southeast Alabama to 250 ft in the southwest part of the state. The Hatchetigbee Formation was
penetrated in the Gulf Refining Company K. Hooks #1 well (OGB #308) well in southwest
Butler County at a depth of 240 ft (124 ft MSL) and was 140 ft thick. It was described by
Raymond and others (1988) as gray, brown, and olive-green, locally cross-bedded, very fine- to
fine-grained sand and interlaminated carbonaceous, sparsely micaceous, silty clay, silt, and
sandy clay. The lower 6 to 35 feet is the Bashi Marl Member, a pale-olive to greenish-gray finegrained, glauconitic, fossiliferous sand and marl containing boulder-sized calcareous sandstone
concretions. The Hatchetigbee Formation in southern Butler County may provide limited
quantities of water for domestic or agricultural use.
CLAIBORNE GROUP
The Claiborne Group is middle Tertiary in age and includes the Tallahatta and Lisbon
Formations in south-central Alabama.
TALLAHATTA FORMATION
The Tallahatta Formation crops out from central Henry County in southeast Alabama,
through extreme southern Crenshaw and Butler Counties in south-central Alabama, to central
Choctaw County in the southwest part of the state. Its thickness varies from about 50 ft in
southeast Alabama to 125 ft in the southwest part of the state. The Tallahatta Formation was
penetrated in the Gulf Refining Company K. Hooks #1 well (OGB #308) well in southwest
Butler County at a depth of 110 ft (254 ft MSL) and was 130 ft thick. It was described in the
subsurface in southeast Alabama by Smith (2001) as predominantly thick sands and thinner sand
units interbedded with thin sandy limestones, sandy clays, and clays. The Tallahatta Formation
14
in only present in parts of extreme southern Butler County and may provide limited quantities of
water for domestic or agricultural use.
LISBON FORMATION
The Lisbon Formation crops out from central Henry County in southeast Alabama,
through extreme northern Covington County, extreme southern Butler County, and northern
Conecuh County in south-central Alabama, and grades into the Gosport Sand/Lisbon Formation
undifferentiated in southern Choctaw County in the southwest part of the state. Smith (2001)
reported that in the subsurface the Lisbon Formation is 60 to 80 ft thick in central Covington
County and is composed of sand; greenish-gray to yellowish-gray, sparingly glauconitic, silty,
and fine- to medium-grained and limestone; light-gray, quartzose sandy, highly fossiliferous,
frequently vugular, highly porous and permeable. The Lisbon Formation in only present in parts
of extreme southern Butler County in outcrop is not a viable aquifer in the county.
HYDROGEOLOGIC ASSESSMENT METHODOLOGY
Aquifers are parts of formal geologic units that are capable of storing and transmitting
useful quantities of groundwater. Geologic strata or beds in the subsurface that contain the
highest percentages of sand and/or limestone and conversely the lowest percentages of silt and
clay are most likely to contain economic quantities of water. Groundwater in these strata is
contained in intergranular pore spaces (storage) and has the critically important property of
interconnectedness of the porosity (permeability) to allow water to flow through the sediments to
wellbores (transmissivity). Thus, locating porous and permeable sand and limestone beds within
geologic formations and determining where they are thickest are important factors in predicting
which geographic areas and geologic units have the greatest potential for containing and
subsequently producing economic quantities of groundwater.
Eighteen geologic units in the Cretaceous and Tertiary Systems, varying in age from
about 135 to 40 million years, underlie Butler County. However, only nine of these have
hydrogeologic characteristics that define them as aquifers in Butler County and, of these, only
one (Ripley Formation) is a proven major aquifer capable of producing adequate quantities of
water for sustainable public, industrial, or irrigation water supply. The Clayton Formation may
have potential for future development, but is currently unproven. The Gordo and Eutaw
Formations, Salt Mountain Limestone, and Nanafalia and Hatchetigbee Formations are minor
15
aquifers due to limiting hydrogeologic characteristics, limited geographic extent, or questionable
water quality, and have limited water source development potential.
WELL DEPTH
Well depth is generally constrained by limiting factors such as the cost associated with
drilling wells and the quantity and quality of water required by the well supply. Well
construction costs are directly related to well depth. Therefore, knowledge of well depths in
particular areas can help reduce unnecessary construction costs. Depths of wells constructed in a
particular aquifer generally correlate with the dip of the geologic formation, so that depths
increase as the distance from the formation outcrop increases. The depth of a well is also
important as related to the quantity and quality of water. Wells may need to be constructed at
depths sufficient to provide adequate water quantity and quality, which relates to the intended
use of the well.
DEPTH TO WATER
Depth to water data are necessary to produce potentiometric surface maps from which
aquifer dynamics such as hydraulic head and gradient can be determined. When subtracted from
the well head elevation, depth to water yields a water level elevation (hydraulic head). The
surface created by mapping the hydraulic head is the potentiometric surface (discussed
separately). Depth to water measured in wells constructed in aquifers of interest supplies
valuable information to guide plans for construction of future wells. Pump size, pump setting
depths, and cost to lift water to the land surface are important issues that depend on depth to
water. With these data, important decisions can be made on economic feasibility and practicality
of a future well.
Depth to water values for selected wells constructed in the Ripley and Clayton aquifers,
were collected from wells with a chalked steel tape, or in some cases, retrieved from the original
driller’s log or public water supplier measurements. Water levels and well head elevations were
recorded along with GPS coordinates to accurately place well locations on project plates. The
water levels were then added to the plates and contoured where possible to show known and
interpolated depth to water within the assessment area.
PUMPING RATES
Pumping rates are influenced by well performance characteristics and aquifer hydraulic
properties such as permeability and transmissivity. Specific yield (discussed separately) can be
16
determined by dividing the pumping rate by the amount of drawdown. Pumping rates and yields
are useful in determining the capability of an aquifer to produce a sustained quantity of water and
avoiding excessive pumping. Effects of excessive pumping (depletion) include well failure,
increased pumping costs, land subsidence and possibly reduction of water in lakes and streams.
Well pumping rates for the Ripley and Clayton aquifers were collected from original
drillers log records and pumping tests. Pumping rates were normalized by casing size and
contoured to depict known and interpolated rates in the assessment area.
SPECIFIC CAPACITY
Well discharge is largely related to aquifer characteristics, but it is also a function of the
mechanical aspects of wells and the required flow rate to meet the needs of the users. Pumping
rates therefore should not be considered the maximum yield of an aquifer at a given location.
Water level and pumping rate data commonly are recorded as drawdown measured during a few
hours of pumping at a specific rate or in some stepped progression of rates during a pumping
test. From these data specific capacity can be calculated and is expressed as gallons per minute
per foot of drawdown (gpm/ft).
Specific capacity data along with estimates of total dynamic head are useful in well
design, wherein pump head-capacity curves can be combined with specific capacity curves to
determine scenarios for well discharge rates (Driscoll, 1986). Specific capacity, though related in
part to well construction and pump test factors, is also a general indicator of aquifer
transmissivity, and empirical mathematical relationships and statistical measures have been
developed for aquifers elsewhere to assist in groundwater development programs and well design
(Robertson, 1963; Theis, 1963; Walton and Neill, 1963; Bradbury and Rothschild, 1985;
Driscoll, 1986; Mace, 1997). Larger populations in urban areas require more water than rural
areas, which is shown in specific capacity data where high capacity wells are concentrated
around population centers. Fewer, more widely spaced, high capacity wells are constructed in
rural areas and are used for rural water utilities, agriculture, and industry. In these cases, specific
capacity maps may provide inaccurate regional depictions of aquifer quality and therefore should
be evaluated with other aquifer data to make accurate judgments of aquifer producibility.
Specific capacities were calculated for selected wells constructed in the Ripley and
Clayton aquifers in the assessment area, normalized by casing size, and contoured to depict the
geographic distribution and magnitude of specific capacity values.
17
NET POTENTIAL PRODUCTIVE INTERVALS
Delineation of porous and permeable zones and the determination of their thicknesses in
this study relied upon the use of geophysical well logs with the aid of drillers’ logs and sample
descriptions. Because geophysical well logs have only been acquired in a portion of the water
wells and oil and gas test holes drilled in the area, the analyses and interpretations presented here
do not constitute a comprehensive study of all wells. Continuous recordings of measurements of
the natural gamma radiation (gamma ray logs) of the subsurface sediments, coupled with
resistivity and spontaneous potential (SP) logs, were the principal means of determining the
likely presence and thicknesses of quartz sand and limestone intervals in formations penetrated
by boreholes. Gamma ray logs are not affected by formation water salinity, whereas resistivity
and spontaneous potential logs are electrical measurements of the formation sediments and their
contained water. Typically not recorded in water well test holes, due to costs and other
considerations, are porosity measuring logging devices. These tools, as well as numerous other
types of logs, have been utilized for years in the oil and gas exploration industry to help
determine porous and permeable beds. This study presents results of a method commonly used in
oil and gas exploration called “net sand mapping” whereby each gamma ray log is calibrated as a
measure of the percent sand and/or limestone. For the purposes of this water source assessment,
summations of the thickness of sand and permeable limestone recorded as the “net potential
productive interval” (NPPI) for each well that penetrated and logged each potential aquifer were
determined. Thicknesses of the NPPI were plotted on maps and the values were contoured. Data
for this assessment were limited to the net thickness in which the percentage of “clean” aquifer
matrix was analyzed to be greater than 75 percent for the logged interval. Limiting the net
thicknesses to this high percentage of “clean” aquifer matrix (less than 25 percent clay or siltsized, or shaly limestone materials) provides optimum analysis of the highest quality aquifer (or
potential productive intervals). It should be noted that maps depicting NPPI thicknesses do not
always coincide with thicknesses of the geologic formations. For example, it is not uncommon
for a geologic formation to thicken southward in the study area, while the net sand/limestone
content thins. Depositional environments, sediment supply, and post-depositional geologic
events determine the thicknesses of the geologic units and affect other characteristics such as
porosity and permeability. It should also be stressed that whereas locating areas of thick NPPIs
does increase the probability of finding usable aquifers, it does not guarantee that desired
18
quantities of groundwater with desired water quality can be obtained. Resistivity logs generally
show higher resistivity values in cleaner sand and limestone intervals where fresh water is
present. Spontaneous potential logs can be helpful as well, especially in determining bed
boundaries. Use of resistivity and SP logs complements the aquifer quality and thickness
determinations, and, though less definitive, they can be used in those wells in which gamma ray
logs were not acquired to give a general estimate of net aquifer thickness. Data generated from
NPPI assessments commonly indicate limits of water production in an evaluated aquifer as a
combination of net aquifer thickness and water-quality (salinity) estimation from geophysical
logs. However, due to the low resistivity character of Cretaceous aquifers in southeast and southcentral Alabama, determinations of salinity from resistivity logs is difficult in these formations.
POTENTIOMETRIC SURFACES AND GROUNDWATER LEVEL IMPACTS
A potentiometric water level is the elevation to which water rises in a properly
constructed well that penetrates a confined aquifer (fig. 5). The potentiometric surface is an
imaginary surface representing the confined pressure (hydrostatic head) throughout all or part of
a confined aquifer. This surface is helpful in determining directions of groundwater movement,
hydraulic gradients, and depths from which water can be pumped at particular locations (Cook
and others, 2013). When water is removed from the aquifer by pumping or by reductions in
recharge, the potentiometric surface will fluctuate accordingly (drawdown/production or climatic
impact) (fig. 5). The difference between pre-pumping static water levels and partially recovered
water levels affected by pumping is termed residual drawdown (Driscoll, 1986). It is important to
note that as long as the potentiometric surface remains above the stratigraphic top of the aquifer,
the aquifer media remains saturated so the declining surface only represents a decline in
hydrostatic pressure. If the water level declines below the stratigraphic top of the aquifer, it
becomes unconfined, possibly causing irreversible formation damage. Presently, no known water
levels in southeast Alabama are in danger of declining below the stratigraphic top of any aquifer.
Therefore, potentiometric surfaces and residual drawdown values provide important information
to determine the effects of water production, strategies for water source protection, and future
water availability (Cook and others, 2013).
Figure 5.—Diagram depicting drawdown and potentiometric surfaces prior to and after
pumping in a confined aquifer (modified from fetter, 1994).
19
Groundwater levels and production impacts were evaluated using three maps prepared for
each aquifer. Initial static water levels (depth to groundwater at or near the time of well
construction) were obtained from well and drillers logs. Water levels were adjusted for mean sea
level elevation, plotted according to location, and contoured to create an initial static
potentiometric surface map. Evaluation of initial static groundwater levels enables understanding
of groundwater conditions prior to or in early stages of pumping.
Due to the temporal progression of aquifer development an intermediate potentiometric
surface map was constructed for the Ripley aquifer to show development and production impacts
up to 1996.
A current potentiometric surface map was prepared using current water levels from all
available wells in the project area for the Ripley and Clayton aquifers. Wells were identified
from GSA well files and Alabama Department of Environmental Management (ADEM) list of
public water supply systems. Current depth to groundwater measurements were made using steel
tape or air line measurement devices, the water levels were adjusted for mean sea level elevation,
plotted according to location, and contoured to create a current potentiometric surface map.
Evaluation of current groundwater levels enables understanding of current groundwater
conditions and calculations of current groundwater storage volumes.
Comparing initial static groundwater levels with current levels enables the calculation of
aquifer drawdown, and characterization of production and/or climactic impacts and changes in
groundwater yield. Impacted areas with adequately spaced wells have isolated water level
impacts related to individual wells. Areas with closely spaced wells create “cones of depression”
where individual well impact areas coalesce to form relatively large potentiometric surface
impacts that may cover tens of square miles. Impact assessments are essential to understand the
geographic extent of impact areas and the potential for additional, future development of
groundwater from specific aquifers and locales.
HYDROGRAPHS AND AQUIFER DECLINE CURVES
Groundwater levels fluctuate almost continuously in response to recharge to and
discharge from aquifers by natural and artificial processes, which can include pumpage from
wells, natural groundwater discharge, recharge from changing rates of precipitation, and
evapotranspiration (DeJarnette and others, 2002). GSA maintains water level files for about 450
20
wells and springs throughout Alabama. Water levels in most of these wells have been measured
semiannually or annually for more than 15 years with many having water level records of more
than 30 years. Groundwater levels in a select group of these wells were used to construct
hydrographs (graphical illustrations of water level fluctuations over a specified time period).
Wells were selected to illustrate various aquifer drawdown trends and to document temporal and
spatial characteristics of declining groundwater levels in major pumpage centers in southeast
Alabama.
Generally, all wells with significant pumping rates will exhibit water level declines due to
the fact that water can be pumped faster than it can move through aquifer material to the well
bore (fig. 5). Most hydrographs will have two regression line frequency signatures. One is a long
wave length related to pumpage or long-term drought. The other is an overprinted short wave
length related to seasonal changes in recharge.
Groundwater levels, measured and recorded throughout the life of a well, can be
displayed on a hydrograph that shows the history of groundwater level fluctuation. Hydrographs
can be used to explain impacts of aquifer confinement, drought, pumpage, and well efficiency.
Regression lines constructed from individual water level measurements collected over many
years describe long-term trends of groundwater fluctuation. In areas where water levels indicate
long-term declines, regression lines are termed “decline curves.” Multiple hydrographs and
decline curves in specific areas and aquifers can be used to evaluate groundwater production
impacts and depressions in potentiometric surfaces, commonly known as “cones of depression,”
to estimate changes in groundwater storage, and to predict future groundwater availability.
HYDROGEOLOGIC ASSESSMENT
Although southeast Alabama has five major and four minor aquifers, stratigraphic facies
and geochemical changes westward across the state cause significant declines in the fresh-water
bearing and transmission characteristics of geologic units. Butler County has only one major
aquifer (Ripley Formation) and one minor aquifer (Clayton Formation) hydrogeologic
assessment focuses on
RIPLEY AQUIFER
Stratigraphic analyses related to this hydrogeologic assessment indicates that the Cusseta
Member of the Ripley Formation may extend westward through Butler County, beyond its
current terminus stated in previous assessments. However, aquifer characteristics described
21
below are representative of the Cusseta and upper unnamed members of the Ripley Formation
combined.
WELL DEPTH
Depths of identified wells constructed in the Ripley aquifer vary from less than 300 ft,
southward to more than 1,000 ft. The shallowest identified well is 280 ft, near the Lowndes
County line in northeast Butler County, and the deepest is 1,081 ft at Georgiana in south-central
Butler County.
DEPTH TO WATER
Depth to water increases gradationally downgradient (south-southwest) at about 25 ft/mi
from about 100 ft in northern Butler County to more than 300 ft in the southern part of the
county (plate 7). Depth to water is affected by drawdown throughout the central part of the
county from Greenville to Georgiana (plate 7).
PUMPING RATES
Pumping rates were examined from selected area public supply wells as well as private
supply and irrigation wells. Pumping rates were normalized with respect to well screen diameter
to provide a better comparison from well to well. Normalized pumping rates vary from 1.25
gallons per inch of screen diameter (g/in) in well B-3-1, a private water supply well in
northeastern Butler County to 102.5 g/in in Georgiana 2 well, a public water supply well in the
south-central part of the county (plate 8).
SPECIFIC CAPACITY
Plate 9 shows normalized specific capacities for wells constructed in the Ripley/Cusseta
aquifer in Butler County. Specific capacities were normalized with respect to well screen
diameter to provide a better comparison from well to well. Normalized specific capacities vary
from .08 gallons per foot of drawdown per inch of screen (g/ft/in) in well B-16-2, a private water
supply well in northeastern Butler County, to 3.2 g/ft/in for well Greenville 5. No discernable
trend is seen in the data, which is probably due to factors related to well construction.
NET POTENTIAL PRODUCTIVE INTERVALS AND DOWNGRADIENT LIMIT OF FRESH WATER
Sand beds of the Cretaceous Ripley Formation and its locally present Cusseta Sand
Member form the major aquifer in the assessment area. The thickest NPPI (175-200 ft) area of
the Ripley/Cusseta aquifer extends from eastern Crenshaw County across central Butler County
22
and into northern Conecuh County and eastern Monroe County (plate 10). Well L-10-1
(Greenville Water Works and Sewer Board well no. 6) had the thickest NPPI in Butler County
(196 ft). From well L-10-1, the NPPI thins northward towards the Ripley outcrop at a rate of
about 13 ft/mi and thins southward to less than 100 ft in northern Covington County and central
Conecuh County (plate 10). The downgradient limit of freshwater occurrence extends from
southernmost Crenshaw County across northern Covington County and central Conecuh County
(plate 10). Therefore, water in the Ripley aquifer throughout Butler County is fresh water.
POTENTIOMETRIC SURFACES AND GROUNDWATER LEVEL IMPACTS
Evaluations of water levels for three time intervals were needed to show the progression
of production impacts from the Ripley aquifer in Butler County. Greenville wells 1, 2, and 3
were constructed prior to 1961. Initial or earliest recorded water levels from these wells along
with water levels from wells in southeast Alabama were used to show the relatively unimpacted
potentiometric surface. Water levels collected from wells constructed prior to 1996 were used to
show changes to the potentiometric surface since 1961 and recent water levels were used to
construct the current potentiometric surface, which shows current production impacts for the
Ripley aquifer.
PRE-1961 STATIC GROUNDWATER LEVELS
Initial static groundwater levels measured in Greenville wells 1, 2, and 3 and Luverne
well L-5 were used with contours from a previous investigation in southeast Alabama to
construct a pre-1961 potentiometric surface for the Ripley aquifer. Greenville well 1 was
constructed in 1946 and had a significant impact on the 1961 potentiometric surface (plate 11).
The impact area in the Greenville area in 1961 covered about two mi2. The hydraulic gradient for
the Ripley aquifer is about 0.0019 (10 ft/mi). Groundwater flow is southward across Butler
County (plate 11).
PRE-1996 STATIC GROUNDWATER LEVELS
Available water levels for wells constructed in the Ripley aquifer prior to 1996 were used
to construct a potentiometric surface indicative of conditions in 1996. The potentiometric surface
shows that water production impacts occurred in northeastern Butler County south of the town of
Fort Deposit, where maximum drawdown was more than 100 ft, the Greenville area, where
maximum drawdown was more than 100 ft, a single well (Butler 4) impact of more than 100 ft.
southwest of Greenville, the Georgiana area, where maximum drawdown was about 40 ft, and
23
the vicinity of the towns of Rutledge and Luverne in central Crenshaw County, where maximum
drawdown was more than 50 ft (plate 12). The impact area in the Greenville area in 1996
covered about 35 mi2.
CURRENT STATIC GROUNDWATER LEVELS
Current static groundwater levels were collected for available wells constructed in the
Ripley aquifer. The water levels were used to construct a potentiometric surface indicative of
current conditions. When compared to 1996 conditions, impact areas are similar with the
exception of expansion of the impact area south of Greenville, due to additional well
construction (plates 12, 13). However, drawdown in individual wells has changed significantly.
Drawdowns in Greenville wells 2 and 4 and Georgiana wells 1 and 2 have increased, while
Butler County Water Authority wells 1, 3, and 4 have partially recovered (plates 12, 13).
Current unimpacted potentiometric groundwater level elevations in the Ripley aquifer
vary from 279 ft MSL near the recharge area in northeastern Butler County to 152 ft MSL at
Georgiana in south-central Butler County (plate 13). The largest drawdown occurs in the Butler
3 well, which has a current water level elevation of about 93 ft MSL (plate 13).
HYDROGRAPHS AND AQUIFER DECLINE CURVES
The Ripley Formation is the major water supply source for Butler County. Wells
constructed in the Ripley aquifer were selected based on the quantity and quality of information
available to generate long-term hydrographs that show varying conditions related to groundwater
production, drought, and seasonal fluctuations that impact the Ripley aquifer. Wells selected
include five public water supply wells, all operated by the city of Greenville. The oldest
available water levels for city of Greenville wells number 1, 2, and 3 were 1964, 1956, and 1964
respectively. No water levels were available for well number 1 between 1964 and 1998, however
the rate of water level decline for that period was about two feet per year (ft/yr) (fig. 6). The
water level recovered about 14 feet from 1998 to 1999 but declined again from 1999 to 2003 at a
rate of 2.3 ft/yr (fig. 6). The water level recovered more than 50 ft during early 2003, possibly
the result of being shut down for well maintenance, but declined back to its pre-2003 level in
mid-2004 (fig. 6). Between 2004 and 2012, well number 1 recovered at a rate of 2.8 ft/yr. Since
late 2012, the rate of recovery increased to 12.5 ft/yr, most likely the result of additional water
supply development and normal precipitation (fig. 6).
24
Figure 6.—Hydrograph showing long-term water levels in Greenville well no. 1.
The water level in Greenville well number 2 declined at a rate of 2.7 ft/yr between 1956
and 1996 (fig. 7). Drawdown during that period was more than 100 ft. Between 1996 and 2002
the water level recovered at a rate of 0.8 ft/yr (fig. 7). As with well number 1, the water level in
well number 2 recovered more than 80 ft from early 2003 to late 2004 (fig. 7). Since 2004, the
water level has recovered at a rate of about 2 ft/yr (fig. 7).
The water level in Greenville well number 3 declined 100 ft (a rate of 2.7 ft/yr) between
1964 and 2001 (fig. 8). Between 2001 and 2012 the rate of decline slowed to about one ft/yr,
with the exception of late 2004 and early 2005, when the water level declined about 40 ft (fig. 8).
Since 2012 the water levels has recovered at a rate of about 12 ft/yr (fig. 8).
The water level in Greenville well number 4 declined about 85 ft between 1972 and 1996
(a rate of about 3.5 ft/yr) (fig. 9). The water level recovered at a rate of about 1.3 ft/yr from 1996
to 2004, was stable from 2004 to 2012, and recovered about 40 ft from mid-2012 to mid-2013
(fig. 9). However, since mid-2013 the water level has declined about 20 ft (fig. 9).
25
Figure 7.—Hydrograph showing long-term water levels in Greenville well no. 2.
Greenville well number 5 has the most widely fluctuating water level of those evaluated,
possibly in response to drought and variable pumping (fig. 10). The water level was relatively
stable from mid-2000 to early 2002, but declined more than 40 ft from early 2002 to early 2003,
before recovering to pre decline levels (fig. 10). From mid-2003 to 2007 the water level declined
at a rate of about 3.3 ft/yr, but has recovered at a rate of about 2.1 ft/yr since 2007 (fig. 10).
CLAYTON AQUIFER
Stratigraphic analyses and hydrogeologic data related to this hydrogeologic assessment
indicates that the Clayton Formation is a widely developed aquifer throughout the assessment
area but is classified as a minor aquifer due to relatively few high capacity wells and potential
water quality issues primarily related to the occurrence of iron. Aquifer and well characteristics
described below are representative of the Clayton aquifer and provide information about current
conditions and potential future aquifer development.
26
Figure 8.—Hydrograph showing long-term water levels in Greenville well no. 3.
Figure 9.—Hydrograph showing long-term water levels in Greenville well no. 4.
27
Figure 10.—Hydrograph showing long-term water levels in Greenville well no. 5.
WELL DEPTH
Depths of identified wells constructed in the Ripley aquifer vary from less than 100 ft, near the
outcrop, southward to about 700 ft, in southern Butler County. The shallowest identified well is
36 ft, near the updip limit in northern Bullock County, and the deepest is 700 ft, south of
Georgiana.
DEPTH TO WATER
Depth to water increases gradationally downgradient (south-southwest) in northern Butler
County at about 10 ft/mi from about 25 ft nearest to the recharge area to more than 75 ft
southwest of Greenville (plate 14). Depth to water is affected by drawdown in individual wells
but no regional drawdown trends occur in the Clayton aquifer in the assessment area (plate 14).
PUMPING RATES
Pumping rates were examined from selected area public supply wells as well as private
supply and irrigation wells. Pumping rates were normalized with respect to well screen diameter
to provide a better comparison from well to well. Normalized pumping rates vary from 1.25 g/in
to 5.0 g/in in well G-28-1, a private water supply well in the west-central part of the county
28
(plate 15). Currently, all known Clayton aquifer wells in Butler County are small diameter with
no pumping rates greater than 20 gpm. No public water supply wells are constructed in the
Clayton aquifer in Butler County.
SPECIFIC CAPACITY
Plate 16 shows normalized specific capacities for wells constructed in the Clayton aquifer
in Butler County. Specific capacities were normalized with respect to well screen diameter to
provide a better comparison from well to well. Normalized specific capacities vary from 0.12
g/ft/in in well C-27-1, a private water supply well in north-central Butler County, to 0.75 g/ft/in
for well F-15-1, a private supply well in the northwestern part of the county. No discernable
trend is seen in the data, which is probably due to factors related to well construction.
NET POTENTIAL PRODUCTIVE INTERVALS AND DOWNGRADIENT LIMIT OF FRESH WATER
Sand and limestone beds of the Tertiary Clayton Formation form a widely developed but
minor aquifer in the assessment area. The minor aquifer designation is due to a lack of high
capacity wells and relatively small production rates from small diameter wells in Butler County.
The thickest NPPI (greater than 125 ft) forms an east-west trending linear area extending from
Elba in west-central Coffee County through southern Crenshaw and Butler Counties (plate 17).
The thick NPPI area in Butler County is about 15 miles wide from Bolling in the central part of
the county to just north of McKenzie in the extreme southern part of the county (plate 17). Well
Q-27-4 (Georgiana Water Works and Sewer Board well no. 6) had the thickest Clayton NPPI in
Butler County (196 ft). The NPPI thins northward towards the Clayton outcrop at a rate of about
6 ft/mi to less than 50 ft in northern Butler County (plate 17). The downgradient limit of
freshwater occurrence extends across central Covington and Conecuh Counties. Therefore, water
in the Clayton aquifer in all of Butler County is fresh water (plate 17).
POTENTIOMETRIC SURFACES AND GROUNDWATER LEVEL IMPACTS
Evaluations of potentiometric surfaces for the Clayton aquifer in Butler County were
evaluated for initial water levels at the time of well construction and for current water levels
measured recently. The resulting comparison of historic and current potentiometric surfaces
provides information about the progression of production or climate impacts on the Clayton
aquifer in the assessment area. Comparison of the two potentiometric surfaces shows that,
although there are a number of wells constructed in the Clayton aquifer in Butler County, there is
essentially no water level impact from production (plates 18, 19). The hydraulic gradient for the
29
Clayton aquifer from historic, initial water levels is about 0.0026 (14 ft/mi). Groundwater flow is
southwestward across Butler County (plate 18). The hydraulic gradient for the Clayton aquifer
from current water levels is about 0.0024 (13 ft/mi). Groundwater flow is south-southwestward
across Butler County (plate 19).
HYDROGRAPHS AND AQUIFER DECLINE CURVES
Long-term water level data is limited for wells constructed in the Clayton aquifer in
Butler County. The GSA GAP maintains long-term water levels (since 1983) for one Clayton
well (K-2) in east-central Butler County. The hydrograph constructed from these data show that
the water level fluctuates seasonally each year, on average, about five ft between 1983 and 1989
(fig. 11). After 1989, the frequency of water level fluctuations became multi-year and increased
to more than 10 ft, on average, most likely in response to drought and more variable precipitation
(fig. 11).
Figure 11.—Hydrograph showing long-term water levels in Clayton aquifer well K-2.
30
WELL CAPTURE ZONES
A capture zone is the area of groundwater contribution to a water well. Knowledge of
capture zones is used to construct wells with proper spacing and production rates to avoid over
production and excessive aquifer drawdown. Also, it is important to know the area of
groundwater contribution to a well so that contaminant sources may be monitored and controlled.
Capture zone analysis provides critical information for groundwater source development and
infrastructure planning. Capture zones may be used to determine the likelihood of interference
of wells constructed in the same aquifer or for determining adequate well spacing in areas where
groundwater development is occurring or may occur in the future. Capture zones were modeled
for 120 wells constructed in eight major aquifers in southeast and south-central Alabama.
Hydrologic data were collected from GSA well files, open-file reports, and field assessments.
The GPTRAC program requires well location, aquifer confinability, transmissivity, hydraulic
gradient, flow direction, the quantity of water production, production time, and aquifer thickness.
The hydraulic gradient (head loss per unit length of water movement) is a particularly important
factor in groundwater production and in the ability to model groundwater flow and the effects of
water production. Groundwater flow rates are directly proportional to the hydraulic gradient, so
that a 50% increase in the hydraulic gradient will result in a 50% increase in the rate of water
flow in a given aquifer sand (Driscoll, 1986). Information required for implementation of the
GPTRAC program was obtained from GSA well files and GSA open file wellhead protection
reports. The shape of each modeled capture zone is based on the hydrologic conditions in the
aquifer and average water production rates. Most capture zones are asymmetrically shaped and
are characterized by a linear component oriented in the direction of groundwater flow. Optimum
well spacing for wells constructed in major aquifers in the project area is given in table 1.
GROUNDWATER EXPLORATION AND
ADDITIONAL GROUNDWATER SOURCE DEVELOPMENT
One of the primary purposes of this GSA Groundwater Assessment Program (GAP)
investigation was to recommend sites for test well drilling in the BCWC service area. Test well
locations were developed from interpretation of field assessments and available hydrogeologic
data. Possible test well construction areas were determined after discussions with BCWC
management and consultants to assure that the needs and requirements of BCWC were addressed
in the location process. General locations are given in this report. However, specific locations
31
will be determined by BCWC based on land availability and engineering requirements. Three
initial requirements for test well locations were areas with optimum NPPIs, areas with adequate
separation from other wells constructed in the same aquifer or other recommended test well
areas, and areas that would permit the most efficient and economical water production while
providing additional water supplies to areas with the most critical need. Based on discussions
with BCWC management and consultants, areas that satisfy, hydrogeologic, engineering, and
future water demand requirements for additional Ripley aquifer development are east of the city
of Greenville along Butler County Road 50 and secondarily, along Butler County Road 10,
southeast of the city of Greenville.
Table 1.—Well capture zones and optimum well spacing for south Alabama aquifers.
Aquifer
Range of
residual
drawdown
(feet)
Average capture
zone area
(mi2)
Optimum well spacing(miles)
Along strike of hydraulic
gradient direction
Up or down gradient
direction
Gordo
0-154
1.9
1.5
2.0
Ripley
0-149
2.6
1.0
2.5
Clayton
0-204
2.0
1.0
2.0
Nanafalia
0-189
1.2
1.0
2.0
Tallahatta
1-119
0.5
1.0
1.5
Tuscahoma
31-119
3.5
1.5
2.5
Lisbon
0-33
0.6
1.0
1.0
Crystal River
0-27
1.0
1.0
1.0
Areas for Ripley aquifer test well drilling, recommended by the GSA GAP.

Area 1 is along Butler County Road 50, east of the Persimmon Creek road crossing.
The NPPI thickness for test wells along County Road 50 varies from about 80 to 120
ft. Optimum well spacing in an east-west direction is about 1 mile. If test well
construction is successful, as many as eight production wells in the Ripley aquifer
could be constructed along County Road 50. Plate 5 shows the configuration
(elevation MSL) of the top of the Ripley Formation. Well depths to penetrate the
entire Ripley/Cusetta aquifer would vary from about -200 ft MSL on the west end of
32
the recommended area to about -100 ft on the east end of the area near the Crenshaw
County line.

Area 2 is along Alabama State Highway 10 from the County Road 50 intersection
southeastward to the Crenshaw County line. Along the western part of the area, care
would need to be taken so that any wells along County Road 50 would not be within
2 miles of any wells constructed along State Highway 10. The NPPI thickness
increases southward from County Road 50 so that test wells constructed along state
Highway 10 would penetrate NPPIs from 90 ft thick at the western end of the area to
more than 175 ft thick on the eastern end of the area. If test well construction is
successful, as many as eight production wells could be constructed along State
Highway 10. Well depths would be consistently about -200 ft MSL throughout
recommended area 2.

Based on hydrogeologic data, the Clayton aquifer may be capable of yielding
economic quantities of water in Butler County. Currently, the aquifer is only
developed for private and agricultural water supplies. NPPI mapping indicates that
the Clayton aquifer productive interval varies from about 75 ft to more than 150 ft
and may be viable as a public water supply source throughout Butler County from
State Highway 10 southward. Plate 6 shows the configuration of the top of the
Clayton Formation. Well depths to evaluate the entire Clayton aquifer would be from
75 ft MSL along State Highway 10 to -100 ft MSL in extreme south Butler County.
However, questions have arisen as to the quality of water (excessive iron) produced
from the Clayton aquifer in Butler County. Currently, the GSA GAP has no analytical
data to determine the quality of Clayton water in Butler County. However,
geochemical characteristics related to depth, pH, and oxidation/reduction potential
would suggest that dissolved iron would not be present in Clayton water in southern
Butler County. As soon as a suitable Clayton well is located in the Greenville area,
the GSA GAP will collect water samples and perform a comprehensive geochemical
assessment to determine the overall quality of water from the Clayton aquifer in
central Butler County.
33
CONCLUSIONS AND RECOMMENDATIONS
All public-water supplies in Butler County are produced from groundwater
sources. Most of this water is produced from the Ripley aquifer. Due to increasing population
and water demands and significant water level declines in the Ripley aquifer, the Butler County
Water Authority and Greenville water Works & Sewer Board joined to form the Butler County
Water Cooperative (BCWC) to maximize resources to develop future water sources. The purpose
of this project was to generate data that can be used by the BCWC to make informed decisions
related to development of new groundwater sources in the County.
The geology of the area of investigation is composed of coastal plain sediments overlying
piedmont crystalline rocks. Coastal plain sediments vary in age from lower Cretaceous to middle
Eocene and are composed of interbedded sand, clay, and limestone deposited in environments
that include marine, marginal marine, and fluvial. These sediments thicken southwestward
toward the center of the Gulf of Mexico basin from about 2,500 ft in central Lowndes County to
more than 8,000 ft in northern Covington County. Detailed descriptions of each geologic unit
underlying Butler County are included in the report text. However, it is concluded that the
Ripley/Cusetta and Clayton aquifers are the only units with viable potential for future public
water supply development. Therefore, the comprehensive hydrogeologic assessment only
includes the Ripley/Cusetta and Clayton aquifers. Specific assessment categories include well
depths, depth to water, pumping rates, specific capacities, NPPI thicknesses, potentiometric
surfaces, water level drawdowns, optimum well spacing, and recommendations for test well
drilling.
Depths of identified wells constructed in the Ripley aquifer vary from less than 300 ft,
southward to more than 1,000 ft. The shallowest identified well is 280 ft, near the Lowndes
County line in northeast Butler County, and the deepest is 1,081 ft at Georgiana in south-central
Butler County. Depth to water increases gradationally downgradient (south-southwest) at about
25 ft/mi from about 100 ft in northern Butler County to more than 300 ft in the southern part of
the county. Normalized pumping rates vary from 1.25 gallons per inch of screen diameter (g/in)
in well B-3-1, a private water supply well in northeastern Butler County to 102.5 g/in in
Georgiana 2 well, a public water supply well in the south-central part of the county. Normalized
specific capacities vary from .08 gallons per foot of drawdown per inch of screen (g/ft/in) in well
B-16-2, a private water supply well in northeastern Butler County, to 3.2 g/ft/in for well
34
Greenville 5. No discernable trend is seen in the data, which is probably due to factors related to
well construction.
The thickest NPPI (175-200 ft) area of the Ripley/Cusseta aquifer extends from eastern
Crenshaw County across central Butler County and into northern Conecuh County and eastern
Monroe County. Well L-10-1 (Greenville Water Works and Sewer Board well no. 6) had the
thickest NPPI in Butler County (196 ft). From well L-10-1, the NPPI thins northward towards
the Ripley outcrop at a rate of about 13 ft/mi and thins southward to less than 100 ft in northern
Covington County and central Conecuh County. Chlorides in excess of drinking water standards
in the Ripley/Cusetta aquifer does not occur in Butler County.
Evaluations of water levels for three time intervals (pre-1961, pre-1996, and current)
were needed to show the progression of production impacts from the Ripley aquifer in Butler
County. Greenville well 1 was constructed in 1946 and had a significant impact on the 1961
potentiometric surface. The impact area in the Greenville area in 1961 covered about two mi2.
The hydraulic gradient for the Ripley aquifer is about 0.0019 (10 ft/mi) and groundwater flow is
southward across Butler County.
The pre-1996 potentiometric surface shows that water production impacts occurred in
northeastern Butler County south of the town of Fort Deposit, where maximum drawdown was
more than 100 ft, the Greenville area, where maximum drawdown was more than 100 ft, a single
well (Butler 4) impact of more than 100 ft. southwest of Greenville, the Georgiana area, where
maximum drawdown was about 40 ft. The impact area in the Greenville area in 1996 covered
about 35 mi2.
When compared to 1996 conditions, current production impact areas are similar with the
exception of expansion of the impact area south of Greenville, due to additional well
construction. However, drawdown in individual wells has changed significantly. Drawdowns in
Greenville wells 2 and 4 and Georgiana wells 1 and 2 have increased, while Butler County Water
Authority wells 1, 3, and 4 have partially recovered.
Hydrographs constructed for key Ripley/Cusetta wells show that the oldest available
water levels for city of Greenville wells number 1, 2, and 3 were 1964, 1956, and 1964
respectively. The rate of water level decline for Greenville well no. 1 between 1964 and 1998
was about two ft/yr. Between 2004 and 2012, well number 1 recovered at a rate of 2.8 ft/yr.
35
Since late 2012, the rate of recovery increased to 12.5 ft/yr, most likely the result of additional
water supply development and normal precipitation.
The water level in Greenville well number 2 declined at a rate of 2.7 ft/yr between 1956
and 1996. Drawdown during that period was more than 100 ft. Between 1996 and 2002 the water
level recovered at a rate of 0.8 ft/yr. As with well number 1, the water level in well number 2
recovered more than 80 ft from early 2003 to late 2004. Since 2004, the water level has
recovered at a rate of about 2 ft/yr.
The water level in Greenville well number 3 declined 100 ft (a rate of 2.7 ft/yr) between
1964 and 2001. Between 2001 and 2012 the rate of decline slowed to about one ft/yr. Since 2012
the water levels has recovered at a rate of about 12 ft/yr.
The water level in Greenville well number 4 declined about 85 ft between 1972 and 1996
(a rate of about 3.5 ft/yr). The water level recovered at a rate of about 1.3 ft/yr from 1996 to
2004, was stable from 2004 to 2012, and recovered about 40 ft from mid-2012 to mid-2013.
However, since mid-2013 the water level has declined about 20 ft.
Greenville well number 5 has the most widely fluctuating water level of those evaluated,
possibly in response to drought and variable pumping rates. The water level was relatively stable
from mid-2000 to early 2002, but declined more than 40 ft from early 2002 to early 2003, before
recovering to pre decline levels. From mid-2003 to 2007 the water level declined at a rate of
about 3.3 ft/yr, but has recovered at a rate of about 2.1 ft/yr since 2007.
Stratigraphic analyses and hydrogeologic data related to this hydrogeologic assessment
indicates that the Clayton Formation is a widely developed aquifer throughout the assessment
area but is classified as a minor aquifer due to relatively few high capacity wells and potential
water quality issues primarily related to the occurrence of iron.
Depths of identified wells constructed in the Ripley aquifer vary from less than 100 ft,
near the outcrop, southward to about 700 ft, in southern Butler County. The shallowest identified
well is 36 ft, near the updip limit in northern Bullock County, and the deepest is 700 ft, south of
Georgiana.
Depth to water increases gradationally downgradient (south-southwest) in northern Butler
County at about 10 ft/mi from about 25 ft nearest to the recharge area to more than 75 ft
southwest of Greenville.
36
Normalized pumping rates vary from 1.25 g/in to 5.0 g/in in well G-28-1, a private water
supply well in the west-central part of the county. Currently, all known Clayton aquifer wells in
Butler County are small diameter with no pumping rates greater than 20 gpm. No public water
supply wells are constructed in the Clayton aquifer in Butler County.
Normalized specific capacities vary from 0.12 g/ft/in in well C-27-1, a private water
supply well in north-central Butler County, to 0.75 g/ft/in for well F-15-1, a private supply well
in the northwestern part of the county.
Sand and limestone beds of the Tertiary Clayton Formation form a widely developed but
minor aquifer in the assessment area. The minor aquifer designation is due to a lack of high
capacity wells and relatively small production rates from small diameter wells in Butler County.
The thickest NPPI (greater than 125 ft) forms an east-west trending linear area extending from
Elba in west-central Coffee County through southern Crenshaw and Butler Counties. The thick
NPPI area in Butler County is about 15 miles wide from Bolling in the central part of the county
to just north of McKenzie in the extreme southern part of the county. Well Q-27-4 (Georgiana
Water Works and Sewer Board well no. 6) had the thickest Clayton NPPI in Butler County (196
ft). The NPPI thins northward towards the Clayton outcrop at a rate of about 6 ft/mi to less than
50 ft in northern Butler County. The downgradient limit of freshwater occurrence extends across
central Covington and Conecuh Counties. Therefore, water in the Clayton aquifer in all of Butler
County is fresh water.
Comparison of the two potentiometric surfaces shows that, although there are a number
of wells constructed in the Clayton aquifer in Butler County, there is essentially no water level
impact from production. The hydraulic gradient for the Clayton aquifer from historic, initial
water levels is about 0.0026 (14 ft/mi). Groundwater flow is southwestward across Butler
County. The hydraulic gradient for the Clayton aquifer from current water levels is about 0.0024
(13 ft/mi). Groundwater flow is south-southwestward across Butler County.
A capture zone is the area of groundwater contribution to a water well. Knowledge of
capture zones is used to construct wells with proper spacing and production rates to avoid over
production and excessive aquifer drawdown. Optimum well spacing for the Ripley aquifer is one
mile east-west and 2.5 miles north-south. Optimum well spacing for the Clayton aquifer is one
mile east-west and 2.0 miles north-south.
37
Possible test well construction areas were determined after discussions with BCWC
management and consultants to assure that the needs and requirements of BCWC were addressed
in the location process. Area 1 is recommended for Ripley/Cusetta aquifer test well drilling east
of Greenville along Butler County Road 50 from the Persimmon Creek crossing to the Crenshaw
County line. Area 2 is recommended for Ripley/Cusetta aquifer test well drilling southeast of
Greenville along Alabama State Highway 10 from the County Road 50 intersection to the
Crenshaw County line. Area 3 is for Clayton aquifer test well drilling and includes all of south
Butler County from Alabama State Highway 10 southward to the Covington County line.
However, prior to Clayton aquifer test well drilling, potential water quality issues, primarily
related to iron in the northern part of Area 3 should be addressed.
REFERENCES CITED
Adams, G. I., Butts, C., Stephenson, L. W., Cooke, C. W., 1933, Geology of Alabama,
Geological Survey of Alabama Special Report 14, 97 p.
Bradbury, K. R., and Rothschild, E. R., 1985, A computerized technique for estimating hydraulic
conductivity of aquifers from specific capacity data: Ground Water, v. 23, no. 2, p. 240245.
Cook, M. R., 1993, The Eutaw aquifer in Alabama: Alabama Geological Survey Bulletin 156,
105 p.
Cook, M. R., 2002, Alternative water source assessment: An investigation of deep Cretaceous
aquifers in southeast and south-central Alabama: Geological Survey of Alabama open file
report, 43 p.
Cook, M. R., Smith, K. M., and Rogers, A. L., 2013, Hydrogeologic characterization and
groundwater source development assessment for the South Bullock County Water
Authority: Geological Survey of Alabama Open-file Report 1309, 26 p.
Davis, M. E., 1987, Stratigraphic and hydrogeologic framework of the Alabama Coastal Plain:
U.S. Geological Survey Water Resource Investigations Report 87-4112, 39 p.
Driscoll, F. G., 1986, Groundwater and wells: St. Paul, Minnesota, Johnson Division, 1089 p.
Fetter, C. W., 1994, Applied Hydrogeology: New York, Macmillan College Publishing
Company, Inc., p. 201.
Geological Survey of Alabama, 2006, Geologic map of Alabama, Digital Version 1.0 (CD):
Geological Survey of Alabama Special Map 220A.
38
Maher, J.C., and Applin, E. R., 1968, Correlation of subsurface Mesozoic and Cenozoic rocks
along the Eastern Gulf Coast: American Association of Petroleum Geologists Cross
Section Publication 6, p. 11-12.
Mace, R. E., 1997, Determination of transmissivity from specific-capacity tests in a karst aquifer:
Ground Water, v. 35, no. 5, p. 738-742.
Neathery, T. L., Bentley, R. D., Higgins, M. W., Zietz, I., 1976, Preliminary interpretation of
aeromagnetic and aeroradioactivity maps of the Alabama Piedmont, Geological Survey
of Alabama Reprint Series 42, in Geology, v. 4, p. 375-381.
Raymond, D. E., Osborne, W. E., Copeland, C. W., Neathery, T. L., 1988, Alabama
Stratigraphy: Alabama Geological Survey Circular 140, 98 p.
Robertson, C. E., 1963, Well data for water well yield map: Missouri Geological Survey and
Water Resources, 23 p.
Sapp, C. D., and Emplaincourt, Jacques, 1975, Physiographic regions of Alabama: Alabama
Geological Survey Special Map 168.
Smith, C. C., 2001, Implementation assessment for water resources availability, protection, and
utilization for the Choctawhatchee, Pea, and Yellow Rivers watersheds: Geological Survey
of Alabama Open-File Report, 148 p.
Smith, C. C., 2009, Lithologic descriptions and geologic assignments of sediments encountered
in Butler County Water Supply District test well no.1, County Highway 50 site, Butler
County, Alabama: Consultants report, 14 p.
Szabo, M. W., Osborne, W. E., Neathery, T. L., and Copeland, C. W., Jr., 1988, Geologic map of
Alabama, southwest sheet (1:250,000): Alabama Geological Survey Special Map 220.
Theis, C. V., 1963, Estimating the transmissivity of a water table aquifer from the specific
capacity of a well: U.S. Geological Survey Water Supply Paper 1536-I, p. 332-336.
Walton, W. C., and Neill, J. C., 1963, Statistical analysis of specific-capacity data for a dolomite
aquifer: Journal of Geophysical Research, v. 68, p. 2251-2262.
39
GEOLOGICAL SURVEY OF ALABAMA
420 Hackberry Lane
P.O. Box 869999
Tuscaloosa, Alabama 35486-6999
205/349-2852
Berry H. (Nick) Tew, Jr., State Geologist
A list of the printed publications by the Geological Survey of Alabama can be
obtained from the Publications Office (205/247-3636) or through our web site
at http://www.gsa.state.al.us/.
E-mail: publications@gsa.state.al.us
The Geological Survey of Alabama (GSA) makes every effort to collect, provide, and maintain accurate
and complete information. However, data acquisition and research are ongoing activities of GSA, and
interpretations may be revised as new data are acquired. Therefore, all information made available to the
public by GSA should be viewed in that context. Neither the GSA nor any employee thereof makes any
warranty, expressed or implied, or assumes any legal responsibility for the accuracy, completeness, or
usefulness of any information, apparatus, product, or process disclosed in this report. Conclusions drawn
or actions taken on the basis of these data and information are the sole responsibility of the user.
As a recipient of Federal financial assistance from the U.S. Department of the Interior, the
GSA prohibits discrimination on the basis of race, color, national origin, age, or disability in its
programs or activities. Discrimination on the basis of sex is prohibited in federally assisted
GSA education programs. If anyone believes that he or she has been discriminated against in
any of the GSA’s programs or activities, including its employment practices, the individual
may contact the U.S. Geological Survey, U.S. Department of the Interior, Washington, D.C.
20240.
AN EQUAL OPPORTUNITY EMPLOYER
Serving Alabama since 1848
40