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Source-linked reports with geographic coverage including Tennessee.

At least 217 records · Page 12Linked to original sources
USGS1991

Effects of septic-tank effluent on ground-water quality in northern Williamson County and southern Davidson County, Tennessee

An investigation of the potential contamination of ground water from septic tank systems blasted in bedrock in Williamson and Davidson Counties, Tennessee, was conducted during 1988-89. Water samples were collected from domestic and observation wells, springs, and surface-water sites in a residential subdivision in the northern part of Williamson County near Nashville. The subdivision has a high density of septic-tank field lines installed into blasted bedrock Water samples also were collected from a well located in an area of Davidson County where field lines were installed in 5 feet of soil. Samples were analyzed for major inorganic constituents, nutrients, total organic carbon, optical brighteners, and bacteria. Although results of analyses of water samples from wells indicate no effect of septic-tank effluent on ground-water quality at these sites, water from two springs located downgradient from the subdivision had slightly larger concentrations of nitrite plus nitrate (2.2 and 2.7 milligrams per liter N), and much larger concentrations of fecal coliform and fecal streptococci bacteria (2,000 to 3,200 and 700 to 900 colonies per 100 milliliters of sample, respectively), than other wells and springs sampled during 1988. Water from one of these springs contained optical brighteners, which indicates that septic-tank effluent is affecting ground-water quality.

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USGS1991

Wetland sedimentation and vegetation patterns near selected highway crossings in West Tennessee

Wetland sedimentation and vegetation patterns at 11 highway crossings in West Tennessee were studied from 1987 to 1989. The purpose of the study was to investigate potential adverse effects of highway crossings on wetlands. Sedimentation rates, determined from root-burial depths, were highly variable. Average rates offine-grained deposition ranged from 0.005 to 0.033 foot per year for stations in locally ponded areas and from -0.002 to 0.039 foot per year for stations in drained areas. Sedimentation rates upstream from highway crossings were not significantly different from downstream rates at 8 of the 11 study sites. Three study sites had significantly greater sedimentation rates downstream. Sand splays were observed downstream from bridges at most study sites. Vegetation patterns and tree growth appear most strongly related to hydropetiod, defined as the average length of time an area is covered by water each year. The influence of sedimentation on tree growth is difficult to separate from the influence of hydroperiod because areas with high sedimentation rates typically have long hydroperiods. Estimated hydroperiod increased no more than 1 percent because of backwater from the highway crossings at the 11 study sites, while the estimated average depth of flood-plain inundation increased by an average of 6 percent.

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USGS1990

Water-quality, well-construction, and ground-water level data for an investigation of radionuclides in ground water, Hickman and Maury counties, Tennessee

Water- quality, well-construction, and ground-water level data were collected for an investigation of radionuclides in ground water in Maury and Hickman Counties, Tennessee. Seventeen wells and 3 springs were sampled in Hickman County, and 20 wells were sampled in Maury County. Data are presented in tables. Maps of each county show the Location of the data-collection sites. Samples from each site were analyzed for radionuclides, common and trace inorganic ions, indicators of redox conditions, selected nutrients, total organic carbon, and selected physical characteristics. Well-construction data were obtained to help determine the source of the water. Where possible, ground-water Level measurements were made for each well sampled. Samples were collected from May 1989 through mid-August 1989.

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USGS1990

Altitude of potentiometric surface, fall 1985, and historic water-level changes in the Memphis aquifer in western Tennessee

Recharge to the Memphis aquifer of Tertiary age is from precipitation on the outcrop, which forms a broad belt across western Tennessee, or by downward infiltration of water from the overlying fluvial deposits of Tertiary(?) and Quaternary age and alluvium of Quaternary age. In the outcrop-recharge belt, where the Memphis aquifer is under water-table conditions, the potentiometic surface is complex and generally conforms to the topography. To the west of the outcrop-recharge belt where the Memphis aquifer is confined, the potentiometric surface gently slopes westward, and water moves slowly in that direction. A major cone of depression in the potentiometric surface in the Memphis area is the result of long-term (1886-present) pumping at municipal and industrial well fields. Data from five observation wells in the Memphis aquifer indicate that water levels have declined at average rates ranging from less than 0.1 to 1.3 feet per year during the period 1928-85. The largest declines have been in the Memphis area, where withdrawals averaged about 191 million gallons per day in 1985. The record from an observation well located near the center of the major cone of depression in the Memphis area indicates that water levels ceased to decline in about 1975 and that the center of the cone essentially has stabilized. The record from another well away from the center of the cone indicates that water levels are still declining at a low rate, and that the cone is still expanding as a result of the effects of pumping. Water levels in large areas of western Tennessee, away from the effects of pumping, have fluctuated only in response to long-term variations in precipitation on the outcrop-recharge belt. Long-term changes in water levels in these areas have been small.

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USGS1990

Geology and ground-water resources of the Cockfield Formation in western Tennessee

The Cockfield Formation of the Claiborne Group of Tertiary age underlies approximately 4,000 sq mi in western Tennessee. The formation consists primarily of lenticular beds of very fine to coarse sand, silt, clay, and lignite. The Cockfield Formation has been extensively eroded, and the original thickness is preserved only in a few areas where the formation ranges from 235 to 270 ft in thickness. Recharge to the Cockfield aquifer is from precipitation on sparse outcrops or by downward infiltration of water from the overlying fluvial deposits of Tertiary and Quaternary age and alluvium of Quaternary age or, where present, the overlying Jackson Formation of Tertiary age. Data from two observation wells indicate that water levels have risen at average rates of about 0.5 and 0.7 ft/year during the period 1980-85. Water from the Cockfield aquifer is a calcium bicarbonate type that contains low concentrations of most major constituents, and generally is suitable for most uses. Dissolved-solids concentrations range from 44 to 218 mg/L. Data from two aquifer tests indicate transmissivities of 2,500 and 6 ,000 sq ft/day and storage coefficients of 0.0003 and 0.0007, respectively. The Cockfield aquifer presently provides small to moderate quantities of water for several public and industrial water supplies and small quantities to numerous domestic and farm wells. Withdrawals for public and industrial supplies in 1983 averaged about 3.3 million gal/day. (USGS)

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USGS1990

Geology and ground-water resources of the Memphis Sand in western Tennessee

The Memphis Sand of the Claiborne Group of Tertiary age underlies approximately 7,400 square miles in western Tennessee. The formation primarily consists of a thick body of very fine to very coarse sand that includes subordinate lenses or beds of clay and silt at various horizons. The Memphis Sand ranges from 0 to about 900 feet in thickness, but where the original thickness is preserved, it is about 400 to 900 feet thick. The Memphis Sand yields water to wells in most of the area of occurrence in western Tennessee and, where saturated, makes up the Memphis aquifer. Recharge to the Memphis aquifer is from precipitation on the outcrop, which is a broad belt across western Tennessee, or by downward infiltration of water from the overlying fluvial deposits of Tertiary(?) and Quatemary age and alluvium of Quatemary age. Long-term data from five observation wells indicate that water levels have declined at average rates ranging from less than 0.1 to 1.3 feet per year during the period 1928-83. The largest declines have been in the Memphis area. Water from the Memphis aquifer generally is a calcium bicarbonate type, but locally is a sodium bicarbonate or mixed type. The water contains low concentrations of most major constituents and generally is suitable for most uses. Dissolved-solids concentrations range from 19 to 333 milligrams per liter. The results from 76 aquifer tests made in the Memphis area and western Tennessee during the period 1949-62 indicate that transmissivities range from 2,700 to 53,500 feet squared per day, and storage coefficients range from 0.0001 to 0.003. The Memphis aquifer provides moderate to large quantities of water for many public and industrial water supplies in western Tennessee and small quantities to numerous domestic and farm wells. Withdrawals for public and industrial supplies in 1983 averaged about 227 million gallons per day, of which 183 million gallons per day were in the Memphis area. The Memphis aquifer has much potential for future use, particularly at places outside the Memphis area.

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USGS1990

Altitude of potentiometric surface, fall 1985, and historic water-level changes in the Fort Pillow aquifer in western Tennessee

Recharge to the Fort Pillow aquifer of Tertiary age is from precipitation on the outcrop, which forms a narrow belt across western Tennessee, and by downward infiltration of water from the overlying fluvial deposits of Tertiary(?) and Quaternary age and alluvium of Quaternary age or, where the upper confining unit is absent, from the overlying Memphis aquifer of Tertiary age. The potentiometric surface in the Fort Pillow aquifer slopes gently westward from the outcrop-recharge area, and the water moves slowly in that direction. A depression in the potentiometric surface in the Memphis area is the result of past pumping at Memphis Light, Gas and Water Division well fields (1924-74), past and present pumping at an industrial well field at Memphis, and the municipal well field at West Memphis, Ark. Withdrawals from the Fort Pillow aquifer in western Tennessee in 1985 averaged about 12 million gallons per day. Water-level data from four observation wells, all in areas affected by pumping, indicate that water levels have declined at average rates ranging from about 0.4 to 0.9footperyearduring the past 40years (1945-85). The greatest rate of decline was as much as 4.0 feet per year between 1945 and 1954 in an observation well in a well field of Memphis Light, Gas and Water Division at Memphis. In 1971, Memphis Light, Gas and Water Division ceased pumping from the Fort Pillow aquifer at this well field, and between 1971 and 1976, water levels rose about 28 feet in this well. Water levels in the Fort Pillow aquifer in large areas of western Tennessee away from the effects of pumping have fluctuated only in response to long-term variations in precipitation on the outcrop-recharge belt. Long-term changes in water levels in these areas have been small.

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USGS1990

Hydrogeology of a hazardous-waste disposal site near Brentwood, Williamson County, Tennessee

Approximately 44,000 gal of industrial solvent wastes were disposed in pits on a farm near Brentwood, Tennessee, in 1978, and contaminants were reported in the soil and shallow groundwater on the site in 1985. In order for the State to evaluate possible remedial-action alternatives, an 18-month study was conducted to define the hydrogeologic setting of the site and surrounding area. The area is underlain by four hydrogeologic units: (1) an upper aquifer consisting of saturated regolith, Bigby-Cannon Limestone, and weathered Hermitage Formation; (2) the Hermitage confining unit; (3) a lower aquifer consisting of the Carters Limestone; and (4) the Lebanon confining unit. Wells generally are low yielding less than 1 gal/min), although locally the aquifers may yield as much as 80 gal/minute. This lower aquifer is anisotropic, and transmissivity of this aquifer is greatest in a northwest-southeast direction. Recharge to the groundwater system is primarily from precipitation, and estimates of average annual recharge rates range from 6 to 15 inches/year. Discharge from the groundwater system is primarily to the Little Harpeth River and its tributaries. Groundwater flow at the disposal site is mainly to a small topographic depression that drains the site. Geochemical data indicate four distinct water types. These types represent (1) shallow, rapidly circulating groundwater; (2) deeper (> than 100 ft), rapidly circulating groundwater; (3) shallow, slow moving groundwater; and (4) deeper, slow moving groundwater. Results of the numerical model indicate that most flow is in the upper aquifer.

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USGS1990

Large springs in the Valley and Ridge Province in Tennessee

Approximately 2,700 miscellaneous discharge measurements for 171 large springs in 28 counties of East Tennessee, predominantly within the Valley and Ridge physiographic province, were analyzed statistically and results tabulated to summarize data useful to the Appalachian Valleys-Piedmont Regional Aquifer System Analysis study. The number of measurements at each spring ranged from 1 to 65. Information from each spring includes station numbers, latitude, longitude, spring name and where data are sufficient, an estimate of the mean discharge and the discharge exceeded by 75%, 50%, and 25% of the miscellaneous measurements. Data are referenced to locations on a 1:1,000 ,000-scale map. The highest mean spring discharge was 32.2 cu ft/sec (14,5000 gallons/min).

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USGS1990

Floods of February 1989 in Tennessee

Rainfall amounts of over 5 inches the night of February 13 and the morning of February 14, 1989, caused flooding in areas of Middle and West Tennessee. The towns of Lebanon in Middle Tennessee and Obion in West Tennessee were most severely affected. Most of the business district in Lebanon and many residential areas in Obion were flooded. Recurrence intervals for 24-hour rainfall totals were as high as 25 years at some sites but most peak discharges had recurrence intervals of less than 10 years. Rainfall amounts for the period February 13-20, 1989, peak stages and discharges for this flood, the peak of record, and a list of discharge measurements made during the flood are documented in this report.

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USGS1990

Recharge rates and aquifer hydraulic characteristics for selected drainage basins in middle and east Tennessee

Quantitative information concerning aquifer hydrologic and hydraulic characteristics is needed to manage the development of ground-water resources. These characteristics are poorly defined for the bedrock aquifers in Middle and East Tennessee where demand for water is increasing. This report presents estimates of recharge rate, storage coefficient, diffusivity, and transmissivity for representative drainage basins in Middle and East Tennessee, as determined from analyses of stream-aquifer interactions. The drainage basins have been grouped according to the underlying major aquifer, then statistical descriptions applied to each group, in order to define area1 distribution of these characteristics. Aquifer recharge rates are estimated for representative low, average, and high flow years for 63 drainage basins using hydrograph analysis techniques. Net annual recharge during average flow years for all basins ranges from 4.1 to 16.8 in/yr (inches per year), with a mean value of 7.3 in. In general, recharge rates are highest for basins underlain by the Blue Ridge aquifer (mean value11.7 in/yr) and lowest for basins underlain by the Central Basin aquifer (mean value 5.6 in/yr). Mean recharge values for the Cumberland Plateau, Highland Rim, and Valley and Ridge aquifers are 6.5, 7.4, and 6.6 in/yr, respectively. Gravity drainage characterizes ground-water flow in most surficial bedrock aquifer in Tennessee. Accordingly, a gravity yield analysis, which compares concurrent water-level and streamflow hydrographs, was used to estimate aquifer storage coefficient for nine study basins. The basin estimates range from 0.002 to 0.140; however, most estimates are within a narrow range of values, from 0.01 to 0.025. Accordingly, storage coefficient is estimated to be 0.01 for all aquifers in Middle and East Tennessee, with the exception of the aquifer in the inner part of the Central Basin, for which storage coefficient is estimated to be 0.002. Estimates of aquifer hydraulic diffusivity are derived from estimates of the streamflow recession index and drainage density for 75 drainage basins; values range from 3,300 to 130,000 ft^2/d (feet squared per day). Basin-specific and site-specific estimates of transmissivity are computed from estimates of hydraulic diffusivity and specific-capacity test data, respectively. Basin-specific, or areal, estimates of transmissivity range from 22 to 1,300 ft^2/d, with a mean of 240 ft^2/d In general, areal transmissivity is highest for basins underlain by the Cumberland Plateau aquifer (mean value 480 ft^2/d) and lowest for basins underlain by the Central Basin aquifer (mean value 79 ft^2/d). Mean transmissivity values for the Highland Rim, Valley and Ridge, and Blue Ridge aquifer are 320,140, and 120 ft^2/d respectively. Site-specific estimates of transmissivity, computed from specific-capacity data from 118 test wells in Middle and East Tennessee range from 2 to 93,000 ft^2/d with a mean of 2,600 ft^2/d Mean transmissivity values for the Cumberland Plateau, Highland Rim, Central Basin, Valley and Ridge, and Blue Ridge aquifers are 2,800,1,200, 7,800, 390, and 65Oft Id, respectively.

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USGS1990

Effects of storm-water runoff on local ground-water quality, Clarksville, Tennessee

Storm-related water-quality data were collected at a drainage-well site and at a spring site in Clarksville, Tennessee, to define the effects of storm-water runoff on the quality of ground water in the area. A dye-trace test verified the direct hydraulic connection between the drainage well and Mobley Spring. Samples of storm run off and spring flow were collected at these sites for nine storms during the period February to October 1988. Water samples were collected also from Mobley Spring and two other springs and two observation wells in the area during dry-weather conditions to assess the general quality of ground water in an urban karst terrain. Evaluation of the effect of storm-water runoff on the quality of local ground water is complicated by the presence of other sources of contaminants in the area Concentrations and load for most major constituents were much smaller in storm-water runoff at the drainage well than in the discharge of Mobley Spring, indicating that much of the chemical constituent load discharged from the spring comes from sources other than the drainage well. However, for some of the minor constituents associated with roadway runoff (arsenic, copper, lead, organic carbon, and oil and grease), the drainage well contributed relatively large amounts of these constituents to local ground water during storms. The close correlation between concentrations of total organic carbon and concentrations of most trace metals at the drainage-well and Mobley Spring sites indicates that these constituents are transported together. Many trace metals were flushed early during each runoff event. Mean storm loads for copper, lead, zinc, and four nutrient species (total nitrogen, ammonia nitrogen, total phosphorus, and orthophosphorus) in storm-water runoff at the drainage-well site were lower than mean storm load predicted from an existing regression model. The overprediction by the model may be a result of the small size of the drainage area relative to the range of drainage areas used in the development of the models, or to the below-normal amounts of rainfall during the period of sampling for this investigation. Loads& in storm-water runoff for 22 constituents were extrapolated from sampled storms to total loads for the period February to October 1988. Calculated loads for trace metals for the period ranged from 0.030pound.s for cadmium to 12pound.s for strontium. Loads of the primary nutrients ranged from 0.97pounds for nitrite as nitrogen to 34pounds of organic nitrogen. Storm-water quality at the drainage-well and Mobley Spring sites was compared to background water quality of the local aquifer; as characterized by dry-weather samples from three springs and two observation wells in the Clarksville area. Concentrations of total-recoverable cadmium, chromium, copper, lead, and nickel were higher in many stormwater samples from both the drainage-well and Mobley Spring sites than in samples from any other site. In addition, concentrations of total organic carbon, methylene blue active substances, and total-recoverable oil and grease were generally higher in storm-water samples from the drainage-well site than in any ground-water sample. Densities of fecal coliform and fecal streptococcus bacteria and concentrations of total recoverable iron, manganese, and methylene blue active substances in storm samples from the drainage-well site exceeded the maximum contaminant levels listed in Tennessee’s drinking-water standards (1988) by as much as 2,500 and 5,500 colonies per 100 milliliters, and 2.7, 0.29, and 0.05 milligrams per liter, respectively. Densities of fecal coliform and fecal streptococcus bacteria and concentrations of total-recoverable iron, manganese, and lead in storm samples from Mobley Spring exceeded the maximum contaminant levels by as much as 500 and 4,500 colonies per 100 milliliters, and 18.7,0.65, and 0.02 milligrams per liter, respectively. For iron, manganese, and bacteria, these undesirable levels are not necessarily attributable to storm-water recharge, because concentrations of these constituents also exceeded drinking-water standards in one or more of the dry-weather samples from selected springs and observation wells in the area.

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USGS1990

Hydrogeology and preliminary assessment of the potential for contamination of the Memphis aquifer in the Memphis area, Tennessee

Detailed maps of the thickness of the Jackson-upper Claiborne confining unit and the altitude of the water table in the alluvium and fluvial deposits provide much new information concerning areas where downward leakage is or may be occurring from the water-table aquifers to the Memphis aquifer in the Memphis area. A detailed map of the altitude of the potentiometric surface of the Memphis aquifer and the locations of 44 sites where contaminants have been detected in the water-table aquifers indicate that many of these sites are located in areas where the direction of ground-water flow in the Memphis aquifer is toward municipal well fields. Consequently, if contaminants enter the Memphis aquifer, a hydraulic potential exists for their transport to those wellfields. Recently (1986-88), volatile organic compounds were detected in water from five municipal wells screened in the Memphis aquifer - three in the Allen well field of the Memphis Light, Gas and Water Division at Memphis and two in the west well field at Collierville. Concentrations of seven volatile organic compounds totaled about 11 micrograms per liter in a sample from one well in the Allen wellfield at Memphis, and the concentration of one compound was 25 micrograms per liter in a sample from one well at Collierville. These are the first reported occurrences of synthetic organic compounds in the Memphis aquifer and prove that the principal aquifer in the Memphis area is vulnerable to contamination.

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USGS1989

Construction, geologic, and water-level data for observation wells near Brentwood, Williamson County, Tennessee

Thirty-four observation wells were installed at 17 sites in the area of a hazardous-waste disposal site near Brentwood, in Williamson County, Tennessee. These wells were installed to supplement data collected from domestic wells in the area, to help define the geology of the study area and to determine the water levels. Both lithologic and geophysical logs were obtained for each well drilled to help define the formations encountered. Four limestone units, corresponding to the Bigby-Cannon limestone, the Hermitage Formation, the Carters Limestone (including the T-3 bentonite), and the Lebanon Limestone, were described from well cuttings and borehole geophysical logs. Water levels have been collected at both the shallow and deep wells at each site.

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USGS1989

Water-resources investigations in Tennessee: Programs and activities of the U.S. Geological Survey, 1988-1989

he following report is the most current in a series of reports published by the Water Resources Division of the US. Geological Survey describing the ongoing water-resources programs and activities in the Tennessee District. These reports provide general information about the projects conducted by the Tennessee District in cooperation with state, local, and other federal agencies. In addition to describing the principal objectives of each program and project, information about the progress of each investigation is provided. The variety of projects conducted by the Tennessee District’s staff normally results in significant new findings. Each year the focus of the programs conducted by the U.S. Geological Survey in Tennessee varies in response to local, state, and federal interests. The local and state interests are addressed through our cooperative investigations program, in which the U.S. Geological Survey provides as much as 50 percent of the funds to conduct investigations. Almost two thirds of the projects in the District are in the cooperative program; the U.S. Geological Survey contributed almost 1.5 million dollars in matching funds to cooperative programs in Tennessee in fiscal year 1989. Federal funds from within the U.S. Geological Survey and other federal agencies financed additional programs at a cost of about 1 million dollars. Technical focus of local and federal programs has shifted during the last few years towards issues addressing hazardous-wastes and ground-water contamination. Many of the projects presented in this report address those issues. Emerging issues such as concerns about wetlands, scour of bridges, quality of storm-water runoff, and droughts, are well represented in the scope of the investigations described in this report. The results of these programs provide significant input to many other activities of the State of Tennessee and the Federal Government that have a direct impact on the quality of life. The information and conclusions obtained from these data-collection programs and investigations are crucial to meet many of the water-supply needs, regulatory, and other water-related issues that the local, state, and federal governments must address. The ability of the U.S. Geological Survey to provide the data to meet these needs resides with the support that the program receives by the State and Federal cooperators. I am pleased with the extent and degree of cooperation that the program receives across the State and from other federal agencies. This report is a testimony to this support. I wish to share these achievements with the dedicated employees of the Tennessee District as well as with the cooperating agencies and their representatives that make this program feasible.

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USGS1989

Geographic information system index for the State of Tennessee

Recently the use of Geographical Information Systems (GIS) has increased within Tennessee. As a result, the U.S. Geological Survey, the Tennessee State Planning Office, and the Tennessee Comptroller of the Treasury entered into an agreement to conduct a survey of GIS users within the State. The objectives were as follows: 1. To conduct and document a survey and subsequently develop a GIS index data base of existing map coverages, location-specific data bases, available transformation software, and transfer techniques that exist at various state, federal, county, and municipal agencies 2. To develop suggested standards for digitized data 3. To promote sharing of data by describing, in general terms, communications techniques that can be used to transfer data from one system to another 4. To create a map coverage of Tennessee and the 7.5minute quadrangle maps within the State that would allow identifi&ztion of existing map coverages for these units through a retrieval from the GIS index data base. Two hundred and sixty three agencies were contacted. One hundred and thirty-nine agencies maintained one or more computer system (including personal computers). Twenty-five agencies used GIS software. The number of coverages or layers that exist upon completion of the survey as computerized digital data for Tennessee was 4,741. One hundred and twenty location-specific data bases were available. The U.S. Geological Survey, National Mapping Division map accuracy standards and digital cartographic data standards were included as minimum guidelines for GIS users. Asynchronous, synchronous, and network communications were also described A data base containing the survey data was built for inquiries. A 7.5-minute quadrangle coverage of Tennessee was created to allow for identification on a quadrangle basis of existing coverages contained in the GIS index data base.

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