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Sergio Garza

Publications and source records attributed to Sergio Garza.

At least 19 recordsLinked to original sources

Approximate potentiometric surfaces for the aquifers of the Texas coastal uplands system, 1980

The National Water Commission recommended that the U.S. Geological Survey conduct intensive studies of the important regional aquifer systems in the United States, particularly those with declining water levels and deteriorating water quality. The result has been a series of Regional Aquifer-System Analysis (RASA) studies, one of which is the West Gulf Coast RASA study (Grubb, 1984). The West Gulf Coast RASA study, which began in 1982, is investigating several major regional aquifers mainly in parts of Missouri, Kentucky, and Tennessee.

Texas↗

Projected effects of proposed chloride-control projects on shallow ground water– Preliminary results for the Wichita River basin, Texas

The U.S. Army Corps of Engineers' plan to control the natural chloride pollution in the Wichita River basin includes the construction of Truscott Brine Lake on a tributary of the North Wichita River. In connection with the proposed brine lake, the U.S. Geological Survey was requested to: (1) Define the existing ground-water conditions in the shallow fresh-water system of the project area; and (2) project the post-construction effects of the proposed lake on the fresh-water aquifer, especially in relation to hydraulic-head changes but also with respect to possible changes in the chemical quality of the ground water. The fresh-water aquifer in the project area is a shallow water-table system with relatively fresh water (generally a calcium sulfate type) that contains approximately 500 to 5,000 milligrams per liter of dissolved solids. The aquifer consists of Permian rocks with very small values of hydraulic conductivity and overlies a brine system (sodium chloride type) that is even less permeable. A thin transition zone separates the fresh-water aquifer and the brine system. Small quantities of infiltration from precipitation throughout the area's watershed constitute the recharge to the aquifer. Discharge from the aquifer consists of the small base flow along creeks; well discharge is negligible. Two-dimensional mathematical computer models were developed for aquifer simulation of: (1) Steady-state conditions in a fresh-water system and (2) transient conditions in a brine- fresh-water system where the density effects of the brine are considered. The main results 'of projecting the effects of the proposed Truscott Brine Lake on the fresh-water aquifer are: (1) Hydraulic head rises of 5 to 40 feet would be confined to areas near the proposed dam and along the lake shoreline, and (2) migration of salt water downstream from the dam generally would be limited to less than 1 mile and apparently would not reach equilibrium during the 100-year duration of the project. The modeling efforts did not include possible effects related to hydrodynamic dispersion in the brine- fresh-water system. Possible changes in the hydraulic conductivity of the aquifer, due to physical and chemical interactions in the brine and fresh-water environments, also were not considered.

Texas↗

Projected effects of proposed salinity-control projects on shallow ground water; preliminary results for the upper Brazos River basin, Texas

As part of the plan to control the natural salt pollution in the upper Brazos River basin of Texas, the U.S. Army Corps of Engineers recommended construction of three impoundment and retention reservoirs. In connection with the proposed reservoirs, the U.S. Geological Survey was requested to define the existing ground-water conditions in the shallow ground-water system of the area and to project the post-construction effects of the reservoirs on the shallow aquifer, especially in relation to aquifer-head changes but also with respect to possible changes in the chemical quality of the ground water. The Corps of Engineers' plan includes a total impoundment reservoir (Kiowa Peak Lake on North Croton Creek) with more than 170,000 acre-feet of storage at the 100-year average pool altitude of 1,550 feet. Croton Lake (23,000 acrefeet of storage at the 100-year average pool altitude of 1,760 feet) on Croton Creek and Dove Lake (no permanent storage) on Salt Croton Creek are projected to hold salt water for transfer to the large Kiowa Peak Lake. The aquifer in the project area is a shallow water-table system with relatively fresh water (calcium sulfate type), in comparison to the saline streamflow, and contains 2,000 to 5,000 milligrams per liter of dissolved solids. The aquifer consists of Permian rocks with very small permeability and is separated from an even less perneable and deeper brine system (sodium chloride type of up to 200,000 milligrams per liter of dissolved solids) by a thin transition zone. Small quantities of infiltration from precipitation in the drainage area constitute the recharge to the aquifer. Discharge from the aquifer consists of the base flow along creeks; well discharge is negligible. Two-dimensional digital-computer models were developed for aquifer simulation of steady and transient conditions in which the density effects of salt water are considered. The models were used to project the effects of the 100- year impoundment of salt water in Kiowa Peak Lake and Croton Lake on the freshwater system. Rises in aquifer head of 10 to 50 feet are projected only for areas near each dan and along each lake shoreline. The maximum migration of salt water downstream from each dam is projected to be about 1 mile. The modeling efforts in this study did not include the effects of hydrodynamic dispersion nor consideration of possible changes in the hydraulic conductivity of the aquifer due to physical and chemical interactions in the salt-water and fresh-water environments.

Open-File Report↗

Altitude of the water table in the alluvial and Wilcox aquifers in the vicinity of Richland and Tehuacana creeks and the Trinity River, Texas, December 1979

This map shows the altitude of the water table in the alluvial and Wilcox aquifers in the vicinity of Richland and Tehuacana Creeks and the Trinity River, Tex., in December 1979. The water-table contours were constructed on the basis of water-level control derived from an inventory of shallow wells in the area, topographic maps, and field locations of numerous small springs and seeps. (USGS)

Open-File Report↗

Appraisal of potential for injection-well recharge of the Hueco bolson with treated sewage effluent : preliminary study at the northeast El Paso area, Texas

The U.S. Geological Survey, in cooperation with the City of El Paso and the Texas Department of Water Resources, made a preliminary study of specific factors related to recharging the Hueco bolson in the northeast El Paso area with treated sewage effluent. The city is interested in the location and spacing of injection wells relative to (1) maintaining the injected effluent in the aquifer for a predetermined amount of time (residence time) before it is pumped out, (2) recovery by pumping of as much of the injected effluent as possible, and (3) the long-term effects of injection on water-level declines. A two-dimensional digital-computer model was developed to project short-term hydraulic gradients under various conditions of pumping and injection. A corresponding range of interstitial velocities (294-773 feet per year) was estimated by assuming idealized piston-type flow. These velocities may be used to plan the location and spacing of production and injection wells under assumed time factors related to the required residence time for the injected water. The injection sites were selected near a proposed sewage-treatment facility in an area that will allow flexibility in the locations of the production and injection wells. Maximum 20-year declines of about 35 feet were projected for areas several miles west and southwest of the facility under anticipated injection and pumping rates. The proposed injection water will require strict water-quality controls, which may involve chlorination and the removal of suspended solids. Mixing of the proposed injection water with the native ground water probably will not clog the aquifer by mineral precipitation. The relatively large concentrations of sodium in the injection water may reduce the hydraulic conductivity of the clay layers in the aquifer, but the permeable sands should not be seriously affected. Plans for an artificial-recharge program need to include an experimental installation to evaluate the system under field conditions.

Open-File Report↗

Projected effects of the proposed Tennessee Colony Reservoir on ground-water conditions in the alluvium of the Trinity River and Cedar Creek, Texas: preliminary results for the Trinidad area

The U.S. Army Corps of Engineers proposed the construction of Tennessee Colony Dam and Reservoir as part of a multipurpose plan for the Trinity River and tributaries between the Dallas-Fort Worth area and the Texas Gulf Coast. The Corps requested the assistance of the U.S. Geological Survey (1) to define the existing ground-water conditions in the alluvium of the Trinity River and Cedar Creek in the Trinidad area, and (2) to project the long-term effects of stresses imposed on the ground-water system by Tennessee Colony Reservoir.

Texas↗

Artificial recharge for subsidence abatement at the NASA-Johnson Space Center, Phase I

Regional decline of aquifer head due to ground-water withdrawal in the Houston area has caused extensive land-surface subsidence. The NASA Johnson Space Center (NASA-JSC) in southeastern Harris County was about 13 to 19 feet (4.0 to 5.8 meters) above mean sea level in 1974 and sinking at a rate of more than 0.2 foot (0.06 meter) per year. NASA-JSC officials, concerned about the hurricane flooding hazard, requested the U.S. Geological Survey to study the feasibility of artificially recharging the aquifers for subsidence abatement.

Open-File Report↗

Projected effects of the proposed Tennessee Colony Reservoir on ground-water conditions in the Carrizo-Wilcox Aquifer and Trinity River alluvium; Trinidad-Oakwood area, Texas

The U.S. Army Corps of Engineers requested the assistance of the U.S. Geological Survey to project the effects of the proposed Tennessee Colony Reservoir on the following ground-water systems: (1) Carrizo-Wilcox bedrock aquifer; (2) the Trinity River alluvium downstream from the proposed Tennessee Colony Dam; and (3) the Trinity River alluvium upstream from the proposed reservoir. The proposed dam site is on the Trinity River south of Trinidad and north of Oakwood. The source of water in the bedrock and alluvial aquifers within the study area is infiltration of rainfall on their respective outcrops. Discharge from these aquifers is by evapotranspiration, seepage to the Trinity River, and pumping from wells.

Texas↗

Geology and ground-water resources of Winkler County, Texas

Winkler County, in west Texas, is adjacent to the southeast corner of New Mexico. Most of the county lies in the Pecos Valley; the remainder, in the northeastern part of the county, is part of the Llano Estacado, or the High Plains. Its principal industries are those related to the production and refining of oil, but ranching also is an important occupation. The county has an arid to semiarid climate, an area of about 887 square miles, and a population of about 12,000 in 1957. The principal fresh-water-bearing formations in Winkler County are the Cenozoic alluvium, which mantles the surface of most of the county, and the Santn Rosa sandstone of Late Triassic age. The alluvium is saturated at a depth ranging from a few feet below the land surface to about 150 feet, and the water is under water-table conditions. The Santa Rosa sandstone is fully saturated throughout most of the county, the water occurring under both unconfined (water-table) and confined (artesian) conditions. The underlying older formations contain water too highly mineralized for most uses, but they are important because water from these underlying beds, which is produced with the oil, is a source of pollution to the fresh-water aquifers. The formations also are a source of water to waterflooding projects for the secondary recovery of oil. The alluvium is replenished chiefly by precipitation, throughout the county. The sand-dune area in the eastern part is the most favorable area of natural recharge. The Santa Rosa sandstone is recharged through the alluvium where the two formations are in contact. Infiltration of saline water, which with oil and waste water has been produced from industrial plants, has been taking place through surface earthen pits. About 18 mgd (million gallons per day) of saline water was being produced from the many oil fields throughout the county during August 1957, and almost all this water was placed in surface pits. The Hendrick oil field alone produced about 14.5 mgd during that month, and an estimated 800,000 acre-feet from 1937 to 1957. About 20 million acre-feet of fresh water is stored in the explored groundwater aquifers of Winkler County, of which an estimated 5 to 7 million acrefeet can be practicably recovered. A daily average of about 8.2 million gallons (9,200 acre-feet per year) of fresh water was used in the county during 1956. Public and industrial use accounted for about 6.8 mgd; irrigation, domestic, and stock uses accounted for 1.4 mgd. Projects engaged in the secondary recovery of oil were the largest consumers, using an average of about 3 mgd of fresh water and about 2.7 mgd of saline water during 1956. Water wells drilled in the deep trough of Cenozoic alluvium south of Wink may yield 1,000 gpm (gallons per minute) or more. A pumping test of the alluvium in that area indicated a coefficient of transmissibility of about 25,000 gpd (gallons per day) per foot. Wells, other than windmill wells, drawing water from thinner sections of alluvium in the rest of the county yield between 100 and 300 gpm. Most of the wells in the Santa Rosa sandstone yield 30-400 gpm. Two municipal wells at Kermit that tap the Santa Rosa sandstone were tested at 1,200 and 1,875 gpm. The large yield of these wells probably results from the presence of fractures in the structurally deformed aquifer. Pumping tests in the Kermit area indicate that locally a full section of the Santa Rosa sandstone has an average coefficient of transmissibility of about 25,000 gpd per foot and a coefficient of storage of about 0.0003. The transmissibility in two other tested areas is much less. The chemical quality of the water in the principal aquifers is generally acceptable for industry and for public supply. About two-thirds of the samples collected from fresh-water wells had a dissolved-solids content of less than 1,000 ppm (parts per million) ; however, some samples in a few areas were hard and were high in fluoride and silica. Samples from wells in polluted areas contained dissolved solids ranging from about 1,400 to 71,100 ppm. Two comprehensive analyses of water samples from the Rustler formation showed a dissolved-solids content of 18,400 ppm. and 157,000 ppm. In most of the water produced with the oil in the Hendrick oil field, the content of dissolved solids ranged from about 4,000 to about 10,000 ppm. The water produced with the oil in the rest of the oil fields in Winkler County was mainly brine.

Water Supply Paper↗