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Hydrogeology and ground-water quality of Lannon-Sussex area, northeastern Waukesha County, Wisconsin

The Silurian dolomite aquifer in the Lannon-Sussex area of southeastern Wisconsin is overlain by glacial deposits, but is within 8 ft of the land surface over 15% of the study area. The proximity of the dolomite aquifer to the land surface makes it susceptible to contamination from man 's activities. Water from the aquifer was analyzed and several characteristics were monitored in a 30-sq-mi area of Waukesha County, including: water temperature, calcium, magnesium, potassium, strontium, alkalinity, chlorides, fluorides, sulfates, nitrites, nitrates, nitrogen, iron, manganese, hardness, and pH. The water is hard, commonly having a hardness of more than 350 mg/L as CaCO 3 , and high in iron, commonly containing more than 0.3 mg/L. However, nutrient concentrations are not high; nitrogen, greater than 8 mg/L; phosphorus, none detected; and potassium, greater than 4 mg/L. The chloride content of the water averages more than 50 mg/L indicating contamination probably from septic systems. The water quality varies over a time. High concentrations of chloride and, occasionally, of bacteria correlate with periods of groundwater recharge over a period of 17 months. Chloride concentrations were highest in water from wells where housing density is high. An attempt was made to relate water quality changes with depth to beds of cherty dolomite that are identified in geologic logs; it was postulated that these zones might be confining beds. Although the beds appear to extend over the area, no evidence was found that they are confining beds, other than reports of a few artesian wells. Water quality, indicated by chloride content, showed no significant relation to well bottom altitudes, casing bottom altitude, or well depth.

Wisconsin↗

Water-quality characteristics of streams in the Piceance Creek and Yellow Creek drainage basins, northwestern Colorado, water years 1977-81

Physical and chemical data for streams in the Piceance Creek and Yellow Creek drainage basins, Colorado collected during the 1977-81 water years are summarized. Stream temperatures ranged from -0.5 to 35.0 degrees Celsius and were warmest near the downstream reaches of Piceance and Yellow Creeks. Minimum concentrations of dissolved oxygen were greater than 3.0 milligrams per liter in Piceance and Yellow Creeks, and concentrations of dissolved oxygen exceeded saturation during periods of active photosynthesis. Values of pH in streams ranged from 6.9 to 9.0 and were least during snowmelt runoff and greatest in low flows in the lower reaches of Piceance and Yellow Creeks. Concentrations of suspended sediment exceeded 100 ,000 milligrams per liter in localized runoff. Specific conductance varied inversely with discharge. Sodium, magnesium, bicarbonate, and sulfate ions and concentration ranges of dissolved solids between 400 and 1,700 milligrams per liter were characteristic of the water quality of the perennial streams. Calcium and bicarbonate dominated the major ions, and concentrations of dissolved solids normally were less than 600 milligrams per liter in the intermittent streams during storm and snowmelt runoff. Augmentation to Piceance and Yellow Creeks from ground-water sources in the lower reaches of both streams increased concentrations of dissolved solids several thousand milligrams per liter during medium and low flows and caused a change in water-quality type from sodium magnesium bicarbonate to a high-percentage sodium bicarbonate. Increases in dissolved concentrations of arsenic, boron, fluoride, lithium, strontium, and sulfate were related to ground-water sources or discharges from areas of energy resource development. (USGS)

Water-Resources Investigations Report↗

Discharge and water quality of springs in Roan and Parachute Creek basins, northwestern Colorado, 1981-83

This report is a compilation and interpretation of discharge, water-quality, and radiochemical data collected at springs in the oil-shale regions of Roan and Parachute Creek basins, Colorado, from 1981 to 1983. Springs located on upland plateaus and ridges are mixed-cation bicarbonate water types with 216 to 713 milligrams per liter dissolved solids. Calcite and dolomite dissolution are dominant chemical reactions in upland springs. Springs located in the canyons contain greater concentrations of sodium and sulfate and have 388 to 3,970 milligrams per liter dissolved solids. Gypsum dissolution is an important chemical reaction in canyon spring water. The only trace constituents with mean concentration greater than 10 micrograms per liter in the study area were barium, boron, lithium and strontium. None of the canyon springs investigated represent discharge from the lower aquifer in the Green River Formation. Analysis of chemical and discharge data for streams in the Roan Creek drainage showed evidence of lower-aquifer discharge into the canyons. Springs located near an oil-shale mine or processing plant could be used for monitoring groundwater quality and quantity. Bicarbonate, fluoride, arsenic, boron, lithium, mercury, ammonia, and organic carbon may be chemical indicators of mine or process-water contamination of shallow aquifers near an oil-shale plant or mine.

Colorado↗

Compilation and preliminary interpretation of hydrologic data for the Weldon Spring radioactive waste-disposal sites, St Charles County, Missouri — A progress report

The Weldon Spring Chemical Plant is located just north of the drainage divide separating the Mississippi River and the Missouri River in St. Charles County, Missouri. From 1957 to 1966 the plant converted uranium-ore concentrates and recycled scrap to pure uranium trioxide, uranium tetrafluoride, and uranium metal. Residues from these operations were pumped to four large pits that had been excavated near the plant. Small springs and losing streams are present in the area. Water overlying the residue in the pits has a large concentration of dissolved solids and a different chemical composition compared to the native groundwater and surface water. This difference is indicated by the concentrations of calcium, sodium, sulfate, nitrate, fluoride, uranium, radium, lithium, molybdenum, strontium, and vanadium, all of which are greater than natural or background concentrations. Water from Burgermeister Spring, located about 1.5 miles north of the chemical plant area, contains uranium and nitrate concentrations greater than background concentrations. Groundwater in the shallow bedrock aquifer moves northward from the vicinity of the chemical plant toward Dardenne Creek. An abandoned limestone quarry several miles southwest of the chemical plant also has been used for the disposal of radioactive waste and rubble. Groundwater flow from the quarry area is southward through the alluvium, away from the quarry and toward the Missouri River. The St. Charles County well field is located in the Missouri River flood plain near the quarry and the large yield wells are open to the Missouri River alluvial aquifer. Water from a well 4,000 ft southeast of the quarry was analyzed; there was no indication of contamination from the quarry. Additional water quality and water level data are needed to determine if water from the quarry moves toward the well field. Observation wells need to be installed in the area between the chemical plant, pits, and Dardenne Creek. The wells would be used to provide access for measurements of depth to ground water and for the collection of water samples from the shallow bedrock aquifer.

Missouri↗

Assessment of low-flow water quality in the Du Page River, Illinois

The relations of several stream processes to concentrations of dissolved oxygen and other constituents during low-flow periods were evaluated for a 70.3-mile reach of the Du Page River in northeastern Illinois, using measured data and computer simulations. Reaeration rates and traveltimes were measured at various flow rates using a steady-state gas-tracer technique. Stream discharge, stage, temperature, and chemical constituent concentrations were measured during two 24-hour periods in July and August 1983. These data were used to describe water quality and to calibrate and verify the QUAL-II one dimensional, steady-state, water quality model. Dissolved oxygen concentrations did not meet the State water quality standards in several subreaches of the Du Page River. Concentrations were consistently below the State minimum dissolved oxygen standard in the downstream 8 miles of the East Branch Du Page River. Model simulations indicate that although ammonia oxidation played a role in the dissolved oxygen depletion, the primary factor was sediment oxygen demand. Other measured chemical constituents that did not comply with the State water quality standards in several subreaches of the river included ammonia, iron, fluoride, and total dissolved solids. (USGS)

Water-Resources Investigations Report↗

Quality of ground water in the Payette River basin, Idaho

As part of a study to obtain groundwater quality data in areas of Idaho were land- and water-resource development is expected to increase, water quality, geologic, and hydrologic data were collected for 74 wells in the Payette River basin, west-central Idaho, from July to October 1982. Historical (pre-1982) data from 13 wells were compiled with more recent (1982) data to define, on a reconnaissance level, water quality conditions in major aquifers and to identify factors that may have affected groundwater quality. Water from the major aquifers generally contains predominantly calcium, magnesium, and bicarbonate plus carbonate ions. Sodium and bicarbonate or sulfate are the predominant ions in groundwater from 25% of the 1982 samples. Areally, groundwater from the upper Payette River basin has proportionately lower ion concentrations than water from the lower Payette River basin. Water samples from wells < 100 ft deep generally have lower ion concentrations than samples from wells > 100 ft deep. Variations in groundwater quality probably are most affected by differences in aquifer composition and proximity to source(s) of recharge. Groundwater in the study area is generally suitable for most uses. In localized areas, pH and concentrations of hardness, alkalinity, dissolved solids, or dissolved nitrite plus nitrate as nitrogen, sulfate, fluoride, iron, or manganese exceed Federal drinking water limits and may restrict some uses of the water.

Idaho↗

Occurrence and availability of ground water in the Athens region, northeastern Georgia

A study was conducted to assess the occurrence and availability of groundwater in the crystalline rocks of the Piedmont area in northeastern Georgia and to determine whether groundwater is a viable alternative or supplemental source for industrial, public and private supplies. The area is underlain by a variety of metamorphic and igneous rocks. The quantity of water that a rock unit can supply to wells is determined by the number, capacity, and interconnection of the secondary openings. Of an estimated 10,000 successful wells drilled in the Athens Region, 972 wells are reported by drilling contractors to supply from 20 to 300 gal/min. Studies of well sites revealed that high yielding wells can be developed only where the water bearing units have undergone significant increases in secondary permeability. This occurs mainly in association with (1) contact zones between rock units of contrasting character, (2) contact zones within multilayered rock units, (3) fault zones, (4) stress-relief fractures, and (5) shear zones. Groundwater may be a viable alternative or supplemental source for industrial, public, and private supplies in much of the Athens Region. In 1980, groundwater made up 38% (18 million gal/day) of the total water used in the area. Yields of 20 to more than 200 gal/min are obtained from wells throughout most of the region, and the water is generally of good chemical quality and is suitable for drinking and many other uses. Concentrations of dissolved constituents are fairly consistent throughout the area. Except for iron, manganese, and fluoride, dissolved constituents rarely exceed drinking water standards. (Lantz-PTT)

Georgia↗

Effects on ground-water quality of seepage from a phosphatic clayey waste settling pond, north-central Florida

Water samples were taken from test wells drilled near an inactive phosphatic clayey waste storage settling pond, from the settling pond and its perimeter ditch, and from an active settling pond near White Springs, Hamilton County, in north-central Florida. The purpose was to document the seepage of chemical constituents from the inactive settling pond and ditch into the adjacent surficial groundwater system, and to assess the potential for movement of these constituents into the deeper Floridan aquifer system which is the major source of public supply in the area. The study area is underlain by a 2 ,500-ft-thick sequence of Coastal Plain sediments of Early Cretaceous to Holocene age. The rocks of Tertiary and Quaternary age that underlie the test site area can be grouped into three major geohydrologic units. In descending order, these units are: surficial aquifer, Hawthorn confining unit, and Floridan aquifer system. Phosphate deposits occur in the upper part of the surficial aquifer. Water in the active settling pond is a calcium magnesium sulfate type with a dissolved solids concentration of 250 mg/L, containing greater amounts of phosphorus, iron, aluminum, barium, zinc, and chromium than the other surface waters. Water in the perimeter ditch is a calcium sulfate type with a dissolved solids concentration of 360 to 390 mg/L, containing greater amounts of calcium, sulfate, nitrogen, and fluoride than other surface waters. Water from the inactive settling pond is a calcium magnesium bicarbonate type with a dissolved solids concentration of 140 mg/L, containing more bicarbonate than the other surface waters. Large amounts of chemical constituents in the phosphate waste disposal slurry are apparently trapped in the sediments of the settling ponds. The quality of water in the upper part of the surficial aquifer from wells within 200 to 400 ft of the inactive settling pond shows no signs of chemical contamination from phosphate industry operations. The horizontal groundwater velocity calculated for this aquifer between the ditch surrounding the settling pond and the test wells is between 100 to 2,000 ft/year, which is enough time for water to have reached the test wells in the 6 years the pond has been operating. (Author 's abstract)

Water-Resources Investigations Report↗

Geohydrology and water quality of the Inyan Kara, Minnelusa, and Madison aquifers of the northern Black Hills, South Dakota and Wyoming, and Bear Lodge Mountains, Wyoming

The Inyan Kara, Minnelusa, and Madison aquifers are the principal sources of ground water in the northern Black Hills, South Dakota and Wyoming, and Bear Lodge Mountains, Wyoming. The aquifers are exposed in the Bear Lodge Mountains and the Black Hills and are about 3,000 to 5,000 ft below the land surface in the northeast corner of the study area. The direction of groundwater movement is from the outcrop area toward central South Dakota. Recharge is by infiltration of precipitation and streamflow is by springs and well withdrawals. All three aquifers yield water to flowing wells in some part of the area. Measured and reported well yields in each of the three aquifers exceed 100 gal/min (gpm). A well open to the Minnelusa Formation and the upper part of the Madison Limestone yielded more than 2 ,000 gpm. Water from the Inyan Kara aquifer may require treatment for gross alpha radiation, iron, manganese, sulfate, and hardness before use in public water systems. Water from the Minnelusa aquifer in the northern one-half of the study area may require treatment for sulfate and hardness before use in public water systems. Water from the Madison aquifer in the northern one-half of the study area may require treatment of fluoride, gross alpha radiation, sulfate, and hardness before use in public water systems. Water from the Minnelusa and Madison aquifers in the southern one-half of the study area, though very hard (more than 180 mg/L hardness as calcium carbonate), is suitable for public water systems and irrigation. Flow between the Minnelusa and the Inyan Kara aquifers appears to be insignificant, based on the results of a digital model results. The model indicated there may be significant recharge to the Minnelusa and Madison aquifers by leakage between these two aquifers and perhaps deeper aquifers. (Author 's abstract)

Water-Resources Investigations Report↗

Streamflow and water quality of the Grand Calumet River, Lake County, Indiana, and Cook County, Illinois, October 1984

A diel (24-hour) water-quality survey was done to investigate the sources of dry-weather waste inputs attributable to other than permitted point-source effluent and to evaluate the waste-load assimilative capacity of the Grand Calumet River, Lake County, Indiana, and Cook County, Illinois, in October 1984. Flow in the Grand Calumet River consists almost entirely of municipal and industrial effluents which comprised more than 90% of the 500 cu ft/sec flow observed at the confluence of the East Branch Grand Calumet River and the Indiana Harbor Ship Canal during the study. At the time of the study, virtually all of the flow in the West Branch Grand Calumet River was municipal effluent. Diel variations in streamflow of as much as 300 cu ft/sec were observed in the East Branch near the ship canal. The diel variation diminished at the upstream sampling sites in the East Branch. In the West Branch, the diel variation in flow was quite drastic; complete reversals of flow were observed at sampling stations near the ship canal. Average dissolved-oxygen concentrations at stations in the East Branch ranged from 5.7 to 8.2 mg/L and at stations in the West Branch from 0.8 to 6.6 mg/L. Concentrations of dissolved solids, suspended solids, biochemical-oxygen demand, ammonia, nitrite, nitrate, and phosphorus were substantially higher in the West Branch than in the East Branch. In the East Branch, only the Indiana Stream Pollution Control Board water-quality standards for total phosphorus and phenol were exceeded. In the West Branch, water-quality standards for total ammonia, chloride, cyanide, dissolved solids, fluoride, total phosphorus, mercury, and phenol were exceeded and dissolved oxygen was less than the minimum allowable. Three areas of significant differences between cumulative effluent and instream chemical-mass discharges were identified in the East Branch and one in the West Branch. The presence of unidentified waste inputs in the East Branch were indicated by differences in the chemical-mass discharges at three sites. Elevated suspended solids, biochemical-oxygen demand, and ammonia chemical-mass discharges at Columbia Avenue indicated the presence of a source of what may have been untreated sewage to the West Branch during the survey. (Author 's abstract)

Illinois, Indiana↗

Chemical characteristics of water in the surficial aquifer system, Dade County, Florida

Geohydrologic test drilling was conducted throughout Dade County to describe the chemical characteristics of water from geohydrologic units in the surficial aquifer system. Water quality analysis of samples collected from the test wells completed in central Dade County indicates that the Biscayne aquifer (unit A), the upper clastic unit of the Tamiami Formation (unit B), and parts of a limestone, sandstone, and sand unit of the Tamiami Formation (unit C) have been effectively flushed of residual seawater, and contain primarily calcium bicarbonate groundwater. The lower parts of unit C and the lower clastic unit of the Tamiami Formation (unit D) primarily contain calcium-sodium bicarbonate or sodium bicarbonate type water. An analysis of variance test indicates that water in units A and B is not significantly (0.05 probability level) different in composition. Mean concentrations of dissolved solids, sodium, and chloride are significantly different between units A and C, whereas mean concentrations of dissolved solids, calcium, sodium, and chloride are significantly different between units A and D. Groundwater in the surficial aquifer system in northwestern Dade County is more mineralized than groundwater that occurs elsewhere in the county (except in coastal areas affected by saltwater). An analysis of variance test indicates that mean concentrations of dissolved solids, sodium, and chloride at sites in northwestern Dade County, developed in units A and C, are significantly different from the mean concentrations of these constituents at sites throughout the rest of the county. Water in this part of the surficial aquifer system is similar to highly mineralized water found in western Broward County. However, in northwestern Dade County, the groundwater has been diluted to a greater extent by less mineralized recharge water. Overall, groundwater in the four major geohydrologic units of the surficial aquifer system of Dade County is suitable for most uses. Maximum concentrations of sodium, chloride, color, fluoride, iron, and dissolved solids in some areas of Dade County, however, exceed maximum contaminant levels established by the Florida Primary and Secondary Drinking Water Regulations standards. (Author 's abstract)

Florida↗

Ground-water quality in Douglas County, western Nevada

A 182% increase in population within the last 10 years in Douglas County, Nevada, has raised concerns by county officials as to the possible effects land development may have on groundwater quality. Most groundwater in Douglas County meets the State of Nevada drinking water standards. Of the 333 water samples used in this analysis, 6 equaled or were greater than the drinking water standards for sulfates, 44 for fluoride, 4 for dissolved solids, 5 for nitrate as nitrate, 12 for arsenic, 33 for iron, and 18 for manganese. Groundwater in the west-central, northern, and northeastern part of Carson Valley is influenced by geothermal water. Some areas in the county may have septic-tank effluent contaminating the groundwater. Temporal changes in most municipal wells showed no overall trend for dissolved-solids and nitrate concentrations spanning the years 1969-83. However, a municipal well in the Topaz Lake area has shown a general increases in the nitrate concentration from 1961 to 1984, but the concentration does not exceed the drinking-water standard. A future groundwater quality monitoring program in Douglas County would include periodic sampling of primary or heavily pumped wells, long-term trend wells, and supplemental wells. (Thacker-USGS)

Nevada↗

Surface-water quality of the Cedar River basin, Iowa-Minnesota, with emphasis on the occurrence and transport of herbicides, May 1984 through November 1985

The surface-water quality in the Cedar River basin was evaluated by analyzing the occurrence, distribution, and transport of common inorganic constituents and selected trace inorganic and organic constituents, with emphasis on herbicides. The surface-water quality of the Cedar River basin was monitored from May 1984 through November 1985. Depth integrated surface-water samples generally were collected monthly at six stations for a considerable range of river discharge. Samples were analyzed for concentrations of common inorganic constituents in the dissolved phase and for concentrations of primary nutrients, trace elements, organic carbon, and herbicides in the dissolved and the dissolved plus suspended phases. Water in the Cedar River was determined to be a calcium bicarbonate type; suspended-sediment concentrations ranged from 3 to 676 milligrams per liter. Concentrations of dissolved fluoride, dissolved nitrite plus nitrate, dissolved arsenic, dissolved lead, and dissolved mercury were less than those of the U.S. Environmental Protection Agency's drinking-water standards for public water supplies. Generally, herbicides were detected only in the dissolved phase, which indicates that herbicides are not being adsorbed on the suspended sediment. However, the lack of detection of adsorbed herbicides also may indicate a need for re-examination of traditionally acceptable methods of treating water samples at the sampling site, separating sediment and water, and extracting organic compounds from sediment. The largest concentrations of several dissolved herbicides were detected after application on agricultural areas in the spring and early summer in both wet and dry periods. However, dissolved atrazine concentrations also increased in the winter during periods of high streamflow resulting from snow melt. The maximum concentration of dissolved herbicides detected at all sampling sites during the study were: alachlor, 21 micrograms per liter; atrazine, 16 micrograms per liter; cyanazine, 8.7 micrograms per liter; metolachlor, 11.0 micrograms per liter; and metribuzin, 3.0 micrograms per liter. Herbicides can be transported from agricultural areas to the river by overland flow, drainage from agricultural areas conveyed by tile drains, and ground water. Hydrograph separation for 10 locations in the Cedar River basin indicates that the ground-water contribution varies within the basin and probably ranges from 56 to 80 percent of the annual river discharge. The predominance of ground-water contribution, the persistent detection of dissolved atrazine even during base flow, and the variety of dissolved herbicides detected in the river during the dry spring of 1985 indicate that some herbicides are being transported to the river by ground water. Atrazine transported to the Cedar River was estimated to be about 1.4 to 4.0 percent of that applied, depending on the assumed application rate. The large river discharge in June 1984, which was predominantly overland flow, contained about 70 percent of the atrazine transported to the river during 1984.

Iowa, Minnesota↗

Quality of water from public-supply wells in principal aquifers of Illinois, 1984-87

The quality of water from public-supply wells that tap the principal aquifers in Illinois are summarized. Water quality data collected during the study included inorganic and volatile organic constituents in 2,756 samples and soluble organic constituents in 330 samples from 2,080 public supply wells. Water quality differs among the aquifers as well as within each aquifer. Groundwater quality generally is suitable for most domestic uses; however, concentrations of iron, dissolved solids , and manganese commonly exceed the States 's general-use and public--and food-processing water supply standards. Water from some wells also contains concentrations of barium, chloride, fluoride, and sulfates that exceed those State standards. Most of these conditions are considered to be the result of natural processes. Volatile organic compounds occurred in more than 300 of the 2,756 samples collected. The sand and gravel aquifers generally are the most susceptible to human-induced contamination; 172 of the 1,047 samples from these aquifers indicate the presence of at least one volatile organic compound. Soluble organic compounds analyzed for included more than 30 pesticides, herbicides, and polychlorinated biphenyls (PCB's). Of the 330 wells sampled, water from only 8 wells had quantifiable concentrations of soluble organic compounds. Water from five wells contained metolachlor, atrazine, alachlor, cyanazine, and metribuzin. Water from three wells contained detectable levels of PCB's. The presence of these soluble organics appears to be limited to wells located near sources of potential contamination. Soluble organic compounds were detected only in wells located near sources of potential contamination. Soluble organic compounds were detected only in wells open to the sand and gravel aquifers. (USGS)

Water-Resources Investigations Report↗

The hydrothermal system in central Twin Falls County, Idaho

Thermal water in Twin Fall County has been used for space heating, large-scale greenhouse operations, and aquaculture since the mid-1970's. More recently, increased utilization of the thermal water has caused aquifer pressures to decline. Near the city of Twin Falls, water levels in some formerly flowing thermal wells have declined to below land surface. The thermal water is principally in the silicic volcanic rocks of the Idavada Volcanics. Electrical resistivity soundings indicate that thickness of the rocks ranges from about 700 to 3,000 ft and averages about 2,000 ft. Temperatures of water sampled range from 26 C to nearly 50 C in wells completed in the upper part of the reservoir near Twin Falls. Water from deeper parts of the reservoir may be warmer than 50 C. Most of the thermal water is a sodium bicarbonate type. The maximum fluoride concentration was 22 mg/L. Chloride concentrations between about 50 and 150 mg/L are the result of mixing of deep water with shallower, cooler water that has been affected by percolation of irrigation water. Carbon-14 concentrations in selected thermal water samples indicate ages of 1,000 to 15,000 years. The water becomes progressively older northward along proposed groundwater flowpaths. On the basis of transit times in the system of 10,000 to 15,000 years and the reservoir volume, recharge is estimated to be about 5 to 7 cu ft/sec. Net heat flux in the area is about 2.2 heat flow units.

Idaho↗

Appraisal of ground-water quality in the Bunker Hill Basin of San Bernardino Valley, California

Water samples were collected from 47 wells and analyzed for concentration of major inorganic ions, nitrogen species, and volatile (purgeable) organic priority pollutants to assess groundwater quality in the Bunker Hill basin, California. Data were supplemented with additional analysis of nitrate, tetrachloroethylene, and trichloroethylene made by other agencies. The organic quality of groundwater in the basin generally is suitable for most uses, although fluoride concentration exceeded the California public drinking water standard of 1.4 mg/L in water from 5 of 47 wells. Nitrate (as nitrogen) concentration equaled or exceeded the public drinking water standard of 10 mg/L in water from 13 of 47 wells sampled for this study and in an additional 19 of 120 samples analyzed by other agencies. Concentration generally decreased with increasing depth below land surface. Twenty-four of the 33 volatile organic priority pollutants were detected in water from wells sampled during this study. When supplemental data from other agencies are included, tetrachloroethylene concentration exceeded the standard of 5 micrograms/L in water from 49 of 128 wells. No basinwide relation between contamination by these two chemicals and well depth or land use was discerned. A network of 11 observation wells that could be sampled twice a year would enhance the monitoring of changes groundwater quality in the Bunker Hill basin. (USGS)

Water-Resources Investigations Report↗

Water quality in Reedy Fork and Buffalo Creek basins in the Greensboro area, North Carolina, 1986-87

Water and bottom-sediment samples were collected from April 1986 through September 1987 at 19 sites in Guilford County and the City of Greensboro, North Carolina. Sampling locations included 13 stream sites, two lakes that supply the City of Greensboro with drinking water, two City of Greensboro finished drinking-water filtration plants, and effluent from the two municipal wastewater plants prior to outfall into receiving streams. Water sampling consisted of six surveys during various stages of steady ground-water flow at all sites and high-flow-event sampling during two storms at six sites. Bottom-sediment samples were collected at three sites during two routine sampling surveys. A summary of nearly 22, 000 separate chemical or physical analyses of water samples or bottom sediment is presented and discussed as individual values, ranges of values, or median values with respect to the locations of sampling sites, streamflow conditions, or other information bearing on water-quality conditions under discussion. The results include discussions of general water-quality indicators; major ion, nutrient, and trace-element concentrations; acid and base/neutral extractable organic compounds; volatile organic compounds; and organochlorine and organophosphorus pesticides detected at each sampling site. Loadings of selected constituents are also estimated on a yearly and daily basis. The quality of the raw and finished water, municipal effluents, and streams in the Greensboro area are characterized by using State and Federal water-quality standards. Inorganic constituents most commonly found in excess of standards were iron, copper, zinc, arsenic, phosphorus, manganese, cyanide, and mercury. Relatively few organic compounds were detected; however, those consistently reported were phthalate, thihalomethane, organophosphorus pesticide, benzol, and phenolic compounds. Selected inorganic, physical, and total organic carbon data are used in a Wilcoxon test for two independent variables to statistically compare water-quality characteristics in selected rural, semideveloped and urban basins. During low-flow sampling, the constituents that differed significantly among all sites were calcium, magnesium, and chloride. During low flows, concentrations of orthophosphate, fluoride, sulfate, and TOC differed at the urban site from the rural and semideveloped and urban sites. There were no significant differences among sites in concentrations of sodium, suspended sediment, nickel, zinc, copper, and mercury during low flows. The Wilcoxon test performed on high-flow data indicated that concentrations of TOC, chloride, sulfate, suspended sediment, and nickel were not significantly different among the sites.

North Carolina↗

Water resources of the upper Big Wood River basin, Idaho

Mean annual water yields, estimated using a water-budget method, for the upper Big Wood River basin above Glendale Road and for Trail Creek, Warm Springs Creek, and East Fork Big Wood River, Idaho were 410,000, 50,000, 60,000 and 50,000 acre-ft, respectively. Yields also were estimated for 1986 and 1987 water years when data were collected for comparison with long-term average values. During 1986, yields estimated for upper Big Wood River basin, Trail Creek, Warm Springs Creek, and East Fork Big Wood were 580,000, 61,000, 83,000 and 60,000 acre-ft, respectively. During 1987, yields estimated for the respective basins were 230,000, 26,000, 32,000 and 28,000 acre-ft. Availability of surface and groundwater varies seasonally; the greatest quantity is available during spring snowmelt, and the least is available during mid-winter to late winter. Nutrient concentrations in sampled ground and surface water were near or below detection levels throughout the basin, which indicates that water quality has not been impaired by increased development. Fluoride concentrations were elevated in Warm Springs Creek, probably due to inflow of thermal water.

Idaho↗