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Tamara Ivahnenko

Publications and source records attributed to Tamara Ivahnenko.

17 recordsLinked to original sources
USGS2024

Predictability and behavior of water transfers across basin boundaries

Inter-basin water transfers (IBTs) are important components of water balances of basins, and they can have substantial impact on regional water availability. Flow information is often not available at locations with known IBTs, which is a drawback in several published IBT databases. Few, if any, studies examine whether IBT flow behavior can be generalized, and if these behaviors can be predicted at undocumented locations or known IBT locations with no flow information. In this study, we employ a clustering method based on image matching to identify similar classes of flow behavior of IBTs. Machine learning models are used to assess how well IBT flow characteristics (e.g., average flow) associated with these behaviors can be predicted. These evaluations of IBTs are done for two regions in the United States. Three primary classes of IBTs (seasonal, nonseasonal/not mixed, and seasonal/mixed) are identified across the two regions analyzed. The IBT flow characteristics are accurately predicted in the northeast region. In the Colorado region, however, only the flow characteristics related to timing were accurately predicted. These results indicate that the proposed modeling framework can be used to identify generalizable IBT flow characteristics. This framework is shown to predict flow characteristics with a reasonable amount of accuracy to undocumented locations and improves previously published IBT databases by backfilling flow information to locations with a known IBT presence.

Arizona, Colorado, Delaware, Kansas, Maryland, Mas↗
USGS2013

Characterization of streamflow, water quality, and instantaneous dissolved solids, selenium, and uranium loads in selected reaches of the Arkansas River, southeastern Colorado, 2009-2010

As a result of continued water-quality concerns in the Arkansas River, including metal contamination from historical mining practices, potential effects associated with storage and movement of water, point- and nonpoint-source contamination, population growth, storm-water flows, and future changes in land and water use, the Arkansas River Basin Regional Resource Planning Group (RRPG) developed a strategy to address these issues. As such, a cooperative strategic approach to address the multiple water-quality concerns within selected reaches of the Arkansas River was developed to (1) identify stream reaches where stream-aquifer interactions have a pronounced effect on water quality and (or) where reactive transport, and physical and (or) chemical alteration of flow during conveyance, is occurring, (2) quantify loading from point sources, and (3) determine source areas and mass loading for selected constituents. (To see the complete abstract, open Report PDF.)

Colorado↗
USGS2011

Nutrient loadings to streams of the continental United States from municipal and industrial effluent?

Data from the United States Environmental Protection Agency Permit Compliance System national database were used to calculate annual total nitrogen (TN) and total phosphorus (TP) loads to surface waters from municipal and industrial facilities in six major regions of the United States for 1992, 1997, and 2002. Concentration and effluent flow data were examined for approximately 118,250 facilities in 45 states and the District of Columbia. Inconsistent and incomplete discharge locations, effluent flows, and effluent nutrient concentrations limited the use of these data for calculating nutrient loads. More concentrations were reported for major facilities, those discharging more than 1 million gallons per day, than for minor facilities, and more concentrations were reported for TP than for TN. Analytical methods to check and improve the quality of the Permit Compliance System data were used. Annual loads were calculated using "typical pollutant concentrations" to supplement missing concentrations based on the type and size of facilities. Annual nutrient loads for over 26,600 facilities were calculated for at least one of the three years. Sewage systems represented 74% of all TN loads and 58% of all TP loads. This work represents an initial set of data to develop a comprehensive and consistent national database of point-source nutrient loads. These loads can be used to inform a wide range of water-quality management, watershed modeling, and research efforts at multiple scales.

Journal of the American Water Resources Associatio↗
USGS2010

Estimated Withdrawals and Use of Water in Colorado, 2005

The future health and economic welfare of the people and environment of Colorado depend on a continuous supply of fresh water. Detailed, comprehensive information on the use of water from Colorado's diverse surface-water and groundwater resources is important to water managers and planners by providing information they need to quantify current stresses and estimate and plan for future water needs. As part of the U.S. Geological Survey's (USGS) National Water Use Information Program (NWUIP), Statewide water withdrawal and water-use data have been collected or estimated and summarized in this report by county and by four-digit hydrologic unit code for the following seven water-use categories: irrigation (crop and golf course), public supply, self-supplied domestic, self-supplied industrial, livestock, mining, and thermoelectric power generation. A summary for instream water use for hydroelectric power generation also is included. This report is published in cooperation with the Colorado Water Conservation Board. In 2005, an estimated 13,581.22 million gallons per day (Mgal/d) was withdrawn from groundwater and surface-water sources in Colorado for the seven water-use categories. Withdrawals from surface water represented about 11,035 Mgal/d, or 81.3 percent of the total, whereas withdrawals from groundwater sources represented an estimated 2,546 Mgal/d or 18.7 percent of the total. Irrigation (combined crop and golf course) totaled 12,362.49 Mgal/d or 91 percent of the total water withdrawals in the State of Colorado. Crop irrigation accounted for 99.7 percent (12,321.85 Mgal/d) of the irrigation, whereas the 243 turf golf courses in Colorado accounted for 0.3 percent (40.64 Mgal/d) of the total irrigation water withdrawals. Total withdrawals for the other water-use categories were public supply, 864.17 Mgal/d; self-supplied domestic, 34.43 Mgal/d; self-supplied industrial, 142.44 Mgal/d; livestock, 33.06 Mgal/d; mining, 21.42 Mgal/d (includes both fresh and saline water); and thermoelectric, 123.21 Mgal/d. The counties with the largest total withdrawals (greater than 500 Mgal/d) were Mesa, Weld, Rio Grande, Montrose, Gunnison, and Saguache. Counties with the smallest total withdrawals (less than 5 Mgal/d) were Clear Creek, Gilpin, and San Juan. Four-digit hydrologic unit codes with the greatest withdrawals were 1019 (South Platte River Basin), 1301 (Rio Grande Basin), and 1102 (Arkansas River Basin); the high withdrawal rates were driven by crop irrigation withdrawals. Total instream water use for hydroelectric power generation was 5,253.60 Mgal/d. Groundwater withdrawals were estimated for 2004 for the bedrock and overlying alluvial aquifers in the Denver Basin for irrigation, public supply, commercial/industrial, household use only, and domestic/livestock water-use categories. Withdrawals were estimated for input into the USGS Denver Basin model by using the equations in the Senate Bill 96-074 groundwater model. The greatest withdrawals were for public supply. The smallest withdrawals were for household-use-only wells. Douglas County had the greatest groundwater withdrawals (183.98 Mgal/d), whereas Broomfield County had the smallest (3.09 Mgal/d). Of the seven Denver Basin aquifers, the Lower Arapahoe aquifer had the greatest total estimated withdrawals (287.11 Mgal/d), with Douglas County having the greatest public-supply withdrawal of any county (95.29 Mgal/d) from this aquifer. The Upper Dawson aquifer was the least used of the Denver Basin aquifers, based on estimated withdrawals of 17.64 Mgal/d. As part of the Colorado Statewide Water Supply Initiative (SWSI), forecasts of future water demand were made based on information such as population, climate, and then-current (2000) water-use information and did not include the effects of future water conservation. Categories compared between estimates in the SWSI baseline forecasted water demand and the USGS water-use compilation were limited to county population and w

Scientific Investigations Report↗
USGS2009

Estimated Colorado Golf Course Irrigation Water Use, 2005

Golf course irrigation water-use data were collected as part of the U.S. Geological Survey National Water Use Program's 2005 compilation to provide baseline information, as no golf course irrigation water-use data (separate from crop irrigation) have been reported in previous compilations. A Web-based survey, designed by the U.S. Geological Survey, in cooperation with the Rocky Mountain Golf Course Superintendents Association (RMGCSA), was electronically distributed by the association to the 237 members in Colorado. Forty-three percent of the members returned the survey, and additional source water information was collected by telephone for all but 20 of the 245 association member and non-member Colorado golf courses. For golf courses where no data were collected at all, an average 'per hole' coefficient, based on returned surveys from that same county, were applied. In counties where no data were collected at all, a State average 'per hole' value of 13.2 acre-feet was used as the coefficient. In 2005, Colorado had 243 turf golf courses (there are 2 sand courses in the State) that had an estimated 2.27 acre-feet per irrigated course acre, and 65 percent of the source water for these courses was surface water. Ground water, potable water (public supply), and reclaimed wastewater, either partially or wholly, were source waters for the remaining courses. Fifty-three of the 64 counties in Colorado have at least one golf course, with the greatest number of courses in Jefferson (23 courses), Arapahoe (22 courses), and El Paso Counties (20 courses). In 2005, an estimated 5,647.8 acre-feet in Jefferson County, 5,402 acre-feet in Arapahoe County, and 4,473.3 acre-feet in El Paso County were used to irrigate the turf grass.

Open-File Report↗
USGS2006

Volatile organic compounds in the nation's ground water and drinking-water supply wells

This national assessment of 55 volatile organic compounds (VOCs) in ground water gives emphasis to the occurrence of VOCs in aquifers that are used as an important supply of drinking water. In contrast to the monitoring of VOC contamination of ground water at point-source release sites, such as landfills and leaking underground storage tanks (LUSTs), our investigations of aquifers are designed as large-scale resource assessments that provide a general characterization of water-quality conditions. Nearly all of the aquifers included in this assessment have been identified as regionally extensive aquifers or aquifer systems. The assessment of ground water (Chapter 3) included analyses of about 3,500 water samples collected during 1985-2001 from various types of wells, representing almost 100 different aquifer studies. This is the first national assessment of the occurrence of a large number of VOCs with different uses, and the assessment addresses key questions about VOCs in aquifers. The assessment also provides a foundation for subsequent decadal assessments of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program to ascertain long-term trends of VOC occurrence in these aquifers.

Circular↗
USGS2006

Sources and occurrence of chloroform and other trihalomethanes in drinking-water supply wells in the United States, 1986-2001

Chloroform and three other trihalomethanes (THMs)--bromodichloromethane, dibromochloromethane, and bromoform--are disinfection by-products commonly produced during the chlorination of water and wastewater. Samples of untreated ground water from drinking-water supply wells (1,096 public and 2,400 domestic wells) were analyzed for THMs and other volatile organic compounds (VOCs) during 1986-2001, or compiled, as part of the U.S. Geological Survey's National Water-Quality Assessment Program. This report provides a summary of potential sources of THMs and of the occurrence and geographical distribution of THMs in samples from public and domestic wells. Evidence for an anthropogenic source of THMs and implications for future research also are presented. Potential sources of THMs to both public and domestic wells include the discharge of chlorinated drinking water and wastewater that may be intentional or inadvertent. Intentional discharge includes the use of municipally supplied chlorinated water to irrigate lawns, golf courses, parks, gardens, and other areas; the use of septic systems; or the regulated discharge of chlorinated wastewater to surface waters or ground-water recharge facilities. Inadvertent discharge includes leakage of chlorinated water from swimming pools, spas, or distribution systems for drinking water or wastewater sewers. Statistical analyses indicate that population density, the percentage of urban land, and the number of Resource Conservation and Recovery Act hazardous-waste facilities near sampled wells are significantly associated with the probability of detection of chloroform, especially for public wells. Domestic wells may have several other sources of THMs, including the practice of well disinfection through shock chlorination, laundry wastewater containing bleach, and septic system effluent. Chloroform was the most frequently detected VOC in samples from drinking-water supply wells (public and domestic wells) in the United States. Although chloroform was detected frequently in samples from public and domestic wells and the other THMs were detected in some samples, no concentrations in samples from either well type exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level of 80 micrograms per liter for total THMs. Chloroform was detected in public well samples almost twice as frequently (11 percent) as in domestic well samples (5 percent). The other three THMs also were detected more frequently in public well samples than in domestic well samples. This detection pattern may be attributed to public wells having a higher pumping capacity than domestic wells. The higher capacity wells create a larger capture zone that potentially intercepts more urban and other land uses and associated point and nonpoint sources of contamination than the smaller capacity domestic wells. THM detection frequencies in domestic well samples show a pattern of decreasing frequency with increasing bromide content, that is in the order: chloroform > bromodichloromethane >= dibromochloromethane >= bromoform. This same pattern has been documented in studies of water chlorination, indicating that an important source of chloroform and other THMs in drinking-water supply wells may be the recycling of chlorinated water and wastewater. Mixtures of THMs commonly occur in public well samples, and the most frequently occurring are combinations of the brominated THMs. These THMs have limited industrial production, few natural sources, and small or no reported direct releases to the environment. Therefore, industrial, commercial, or natural sources are not likely sources of the brominated THMs in public and domestic well samples. The THM detection frequency pattern, the co-occurrence of brominated THMs, and other lines of evidence indicate that the recycling of water with a history of chlorination is an important source of these compounds in samples from drinking-water supply wells.

Scientific Investigations Report↗
USGS2004

Chloroform in the hydrologic system--sources, transport, fate, occurrence, and effects on human health and aquatic organisms

Chloroform is one of the volatile organic compounds (VOCs) detected most frequently in both ground and surface water. Because it is also one of the four trihalomethanes (THMs) produced in the highest concentrations during the chlorination of drinking water and wastewater, the frequent detection of this compound in ground and surface water of the United States is presumed to be caused primarily by the input of chlorinated water to the hydrologic system. Although anthropogenic sources of the compound are substantial, they are currently estimated to constitute only 10 percent of the total global input to the hydrologic system. Natural sources of the compound include volcanic gases, biomass burning, marine algae, and soil microorganisms. Under most conditions (except in the presence of unusually high bromide concentrations), chloroform is the THM produced in the highest concentrations during chlorination. Furthermore, in most cases where more than one THM is produced from chlorination, the relative concentrations among the different compounds usually decrease with increasing bromination (chloroform > dichlorobromomethane > chlorodibromomethane > bromoform). This phenomenon is presumed to be responsible for the common observation that when more than one THM is detected during investigations of the occurrence of these compounds in the hydrologic system, this same trend is typically observed among their relative concentrations or, for a uniform reporting limit, their relative frequencies of detection. This pattern could provide a valuable means for distinguishing between chlorinated water and other potential sources of chloroform in the environment. Chloroform has been widely detected in national, regional, and local studies of VOCs in ground, surface, source, and drinking waters. Total THM (TTHM) concentrations of the compound, however, were typically less than the Maximum Contaminant Level (MCL) of 80 ?g/L (micrograms per liter) established by the U.S. Environmental Protection Agency (USEPA) for TTHMs. In the studies that compared land-use settings, frequencies of detection of chloroform were higher beneath urban and residential areas than beneath agricultural or undeveloped areas. Because chloroform is a suspected human carcinogen, its presence in drinking water is a potential human health concern. Liver damage, however, is known to occur at chloroform exposures lower than those required to cause cancer, an observation that has been considered by the USEPA as the basis for setting a new, non-zero Maximum Contaminant Level Goal of 70 ?g/L for the compound. As part of its National Water-Quality Assessment Program, the U.S. Geological Survey has been assembling and analyzing data on the occurrence of VOCs (including chloroform) in ground and surface water on a national scale from studies conducted between 1991 and the present. This report presents a summary of current (2004) information on the uses, sources, formation, transport, fate, and occurrence of chloroform, as well as its effects on human health and aquatic organisms.

Scientific Investigations Report↗
USGS2003

Occurrence and temporal variability of methyl tert -butyl ether (MTBE) and other volatile organic compounds in select sources of drinking water : results of the focused survey

The large-scale use of the gasoline oxygenate methyl tert -butyl ether (MTBE), and its high solubility, low soil adsorption, and low biodegradability, has resulted in its detection in ground water and surface water in many places throughout the United States. Studies by numerous researchers, as well as many State and local environmental agencies, have discovered high levels of MTBE in soils and ground water at leaking underground gasoline-storage-tank sites and frequent occurrence of low to intermediate levels of MTBE in reservoirs used for both public water supply and recreational boating. In response to these findings, the American Water Works Association Research Foundation sponsored an investigation of MTBE and other volatile organic compounds (VOCs) in the Nation's sources of drinking water. The goal of the investigation was to provide additional information on the frequency of occurrence, concentration, and temporal variability of MTBE and other VOCs in source water used by community water systems (CWSs). The investigation was completed in two stages: (1) reviews of available literature and (2) the collection of new data. Two surveys were associated with the collection of new data. The first, termed the Random Survey, employed a statistically stratified design for sampling source water from 954 randomly selected CWSs. The second, which is the focus of this report, is termed the Focused Survey, which included samples collected from 134 CWS source waters, including ground water, reservoirs, lakes, rivers, and streams, that were suspected or known to contain MTBE. The general intent of the Focused Survey was to compare results with the Random Survey and provide an improved understanding of the occurrence, concentration, temporal variability, and anthropogenic factors associated with frequently detected VOCs. Each sample collected was analyzed for 66 VOCs, including MTBE and three other ether gasoline oxygenates (hereafter termed gasoline oxygenates). As part of the Focused Survey, 451 source-water samples and 744 field quality-control (QC) samples were collected from 78 ground-water, 39 reservoir and (or) lake, and 17 river and (or) stream source waters at fixed intervals for a period of 1 year. Using a common assessment level of 0.2 μg/L (micrograms per liter) (2.0 μg/L for methyl ethyl ketone), 37 of the 66 VOCs analyzed were detected in both surveys. However, VOCs, especially MTBE and other gasoline oxygenates, were detected more frequently in the Focused Survey than in the Random Survey. MTBE was detected in 55.5 percent of the CWSs sampled in the Focused Survey and in 8.7 percent of those sampled in the Random Survey. Little difference in occurrence, however, was observed for trihalomethanes (THMs), which were detected in 16.4 and 14.8 percent of Focused Survey and Random Survey CWSs, respectively. This may indicate a pervasive occurrence of THMs in several source-water types, regardless of CWS size or geographic location. Using data at or above the method detection limit to assess temporal variability and anthropogenic factors associated with frequent detection of select VOCs, concentrations in the Focused Survey in ground-water, reservoir, and river source waters were typically less than 1 μg/L. Also, at a 95-percent confidence interval, no statistically significant differences were observed in comparing concentrations in the first and second ground-water sample. A weak seasonal pattern was observed in samples collected from reservoirs and lakes where gasoline oxygenates and other gasoline compounds were detected more frequently during spring and summer, presumedly a result of increased use of motorized watercraft during these seasons. In contrast, seasonal patterns were not observed in samples collected from rivers and streams. The lack of seasonal differences in river and stream source waters sampled may indicate a common and continuous source of contamination. The most frequently detected VOC (MTBE) and the two most frequently occurring subgroups of VOCs (gasoline oxygenates and THMs) detected in CWS source waters were further characterized to evaluate some anthropogenic factors that may better explain their frequent occurrence. Gasoline oxygenates were detected in 73.9 percent of all CWSs sampled. The concentration of gasoline oxygenates was slightly correlated with watercraft use on reservoirs inside MTBE high-use areas (r2=0.3783) but not outside of these areas (r2=0.0242). In general, the concentration of gasoline oxygenates increased as watercraft use increased. THMs were detected in 47.8 percent of the CWSs supplied by surface water. The frequent occurrence of THMs in reservoir source waters was determined to be an artifact of disinfection and the recycling of chlorinated water to these reservoirs. All CWSs with frequent occurrence of THMs served by a reservoir indicated that chlorine was added to waters for various reasons and that the chlorinated water was then released back to, or upstream of, the reservoir or lake that was sampled.

Water-Resources Investigations Report↗
USGS1997

Relation of hydrogeologic characteristics to distribution of radioactivity in ground water, Newark Basin, New Jersey

The distribution of radioactivity in ground water in the Newark Basin is controlled by the lithology of the aquifer and the degree of contact between the water that flows through the fractured strata and the radioactive lithologic units. The primary water-bearing lithologic units of the Newark Basin that contain elevated levels of radioactivity are the arkosic sandstones of the Stockton Formation and the black mudstones of the lower part of the Passaic Formation. Lithologic and hydrogeologic characteristics of these rock aquifers that affect the spatial distribution of radionuclides in the water include the concentration of radioactive minerals in the strata; the continuity of radioactive strata; the orientation, depth, interconnectedness, and continuity of regional and local fracture patterns; and the geochemical environment, which affects radionuclide solubility. The stratigraphic zones of uranium enrichment and the continuity of the radioactive strata differ between the Stockton Formation and the lower part of the Passaic Formation. Uranium enrichment in both formations, however, is identified in permeable sections of strata that have sharp contacts with, or that are enclosed by, less permeable zones. In the Stockton Formation, basal conglomerates overlying fine-grained mudstones are the most radioactive lithology. In interbedded red and black mudstones of the lower part of the Passaic Formation, the uranium-rich zones are the black and white carbonate-rich siltstone and mudstone laminae overlying massive fine-grained mudstones. Most samples of the arkosic sandstones of the Stockton Formation tended to be slightly enriched in uranium relative to thorium, whereas all samples of the black mudstones of the lower part of the Passaic Formation were heavily enriched in uranium with respect to thorium, with a maximum concentration of uranium of 6,200 parts per million (ppm). Spatial orientation of radioactive zones is controlled by the depositional environment of the host lithology. Radioactive strata in the arkosic sandstones of the Stockton Formation, which is deltaic or fluvial/deltaic in origin, arc stratigraphically discontinuous and nonplanar. In contrast, the radioactive lacustrine black mudstones of the lower part of the Passaic Formation are laterally continuous and planar. Geophysical logs of boreholes indicate that the number and depths of probable waterbearing fractures are greater in the arkoses of the Stockton Formation and red mudstones of the lower part of the Passaic Formation than in the interbedded red and black mudstones of the lower part of the Passaic Formation, despite the fact that fracture-density counts in cores indicate that black mudstones are more highly fractured than the other rock types. The total number of fractures is greater and bedding-plane fractures are generally more common in the lower part of the Passaic Formation than in the Stockton Formation. Fractures in the Stockton Formation form a well-connected network consisting of both bedding-plane and several sets of high-angle fractures present on a regional scale. The large-scale continuity of interconnected bedding-plane fractures and high-angle regional fractures may be partly responsible for the higher yields observed for wells in the Stockton Formation than for wells in the Passaic Formation and may facilitate migration of dissolved radionuclides far from their source. The well-connected fracture network may increase the likelihood that circulating water comes in contact with radioactive strata. Water in the black mudstones of the lower part of the Passaic Formation may also contain high levels of radioactivity, primarily as a result of the high frequency of radioactive strata and of fracturing, rather than the presence of a well-connected regional fracture system. Ground-water chemistry is dominated by the calcium cation and the bicarbonate anion, both derived from abundant secondary calcite in the fractures. The concentrations of uranium and radium in water that comes into contact with radioactive rock are controlled by the water chemistry. Uranium is the dominant alpha emitter in the oxidizing waters in the red mudstones of the Passaic Formation, whereas radium-226 (226Ra) is the dominant alpha emitter in the suboxic (reducing) water in the black mudstones of the lower part of the Passaic Formation. Because the lithology of the Stockton Formation and, in places, the lower part of the Passaic Formation varies greatly, wells can intercept multiple fracture zones that can contain oxic or suboxic waters, thereby resulting in the presence of both uranium and radium in detectable quantities in the same water sample.

New Jersey↗
USGS1996

Use of an ultra-clean sampling technique with inductively coupled plasma-mass spectrometry to determine trace-element concentrations in water from the Kirkwood-Cohansey Aquifer system, coastal plain, New Jersey

Water samples were collected during 1993 from 22 public supply wells screened in the Kirkwood-Cohansey aquifer system; concentrations of 18 trace elements were determined primarily by using inductively coupled plasma-mass spectrometry (ICP-MS) techniques, though graphite furnace atomic adsorption, hydride generation, and cold- vapor flameless atomic adsorption techniques were used for thallium, arsenic, and mercury, respectively, at the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL). In addition, laboratory measurements of alkalinity and turbidity were made. The ground-water samples were collected by using ultra-clean sampling protocols developed by the USGS for collecting ground-water samples in areas with water containing low concentrations of trace elements. This technique is based on recently gained experience in sampling surface water for these elements. Field parameters (water temperature, specific conductance, pH, and dissolved-oxygen concentration) were monitored prior to sample collection. Three equipment blanks were collected to ensure that low-level trace-element contamination did not occur during sample collection. One split sample and a commercially- prepared reference standard were submitted to the NWQL o evaluate laboratory precision and accuracy, respectively. Trace-element concentrations in 10 sample splits and one equipment blank were also determined at the Rutgers University Chemistry Department laboratory. Results of the ICP-MS analyses and cold vapor flameless atomic absorption indicated that five trace elements-- cobalt, copper, lead, mercury, and nickel--were detectable in low concentrations (<0.1-29 mg/L) in most of the samples from the 22 wells, and four elements--aluminum, barium, manganese and zinc--were detected in higher concentrations than the other elements (30-710 mg/L for aluminum; 4-180 mg/L for barium, manganese, and zinc). The remaining nine trace elements were present in concentrations consistently lower than the minimum reporting limit. Turbidity was low (less than 1 nephelometric turbidity unit (NTU)), indicating that the trace-element concentrations were present in the dissolved phase and ideally would be reproducible in the absence of highly variable concentrations of particulates. The concentration of lead in one sample exceeded the U.S. Environmental Protection Agency (USEPA) action level of 15 mg/L; concentrations ranged from <1 to 16 mg/L. Mercury was frequently detected; concentrations ranged from <0.1 to 1.1 mg/L but did not exceed the USEPA maximum contaminant level. Results of analyses of the equipment blanks indicated that samples collected by using the new ultra-clean sampling protocols were free of low-level (< 1mg/L) trace-element contamination. The analysis of the split sample sent to the NWQL had a difference of 5 percent or less for all constituents except aluminum, for which the analysis had a difference of 10 percent. Results of ICP-MS analyses of split water samples sent to the Rutgers University Chemistry Department laboratory were, in general, in good agreement (within 10 percent) with those of the NWQL. Results of the analysis of the commercial standard agreed (within 5 percent) with the known concentrations of the trace elements. The quality-assurance data (three blanks, one split sample, and one standard), although not statistically evaluated because of the small data set, indicate that the measured trace-element concentrations are precise and accurate and that the samples were free of contamination at the microgram-per-liter level of contamination.

Open-File Report↗
USGS1994

Agricultural pesticides in six drainage basins used for public water supply in New Jersey, 1990

A reconnaissance study of six drainage basins in New Jersey was conducted to evaluate the presence of pesticides from agricultural runoff in surface water. In the first phase of the study, surface-water public-supply drainage basins throughout New Jersey that could be affected by pesticide applications were identified by use of a Geographic Information System. Six basins--Lower Mine Hill Reservoir, South Branch of the Raritan River, Main Branch of the Raritan River, Millstone River, Manasquan River, and Matchaponix Brook--were selected as those most likely to be affected by pesticides on the basis of calculated pesticide-application rates and percentage of agricultural land. The second phase of the project was a short-term water-quality reconnaissance of the six drainage basins to determine whether pesticides were present in the surface waters. Twenty-eight surface-water samples (22 water-quality samples, 3 sequentially collected samples, and 3 trip blanks), and 6 samples from water-treatment facilities were collected. Excluding trip blanks, samples from water-treatment facilities, and sequentially collected samples, the pesticides detected in the samples and the percentage of samples in which they were detected, were as follows: atrazine and metolachlor, 86 percent; alachlor, 55 percent; simazine, 45 percent; diazinon, 27 percent; cyanazine and carbaryl, 23 percent; linuron and isophenfos, 9 percent; and chlorpyrifos, 5 percent.Diazinon, detected in one stormflow sample collected from Matchaponix Brook on August 6, 1990, was the only compound to exceed the U.S. Environmental Protection Agency's recommended Lifetime Health Advisory Limit. Correlation between ranked metolachlor concentrations and ranked flow rates was high, and 25 percent of the variance in metolachlor concentrations can be attributed to variations in flow rate. Pesticide residues were detected in samples of pretreated and treated water from water-treatment facilities. Concentrations of all pesticides detected in the treated water were lessthan the U.S. Environmental Protection Agency's recommended Lifetime Health Advisory Limits.

Water-Resources Investigations Report↗
USGS1991

Electromagnetic terrain conductive and ground penetrating radar investigation at and near the Ciba-Geigy Superfund site, Ocean County, New Jersey: quality control assurance plan and results

Ground water is the principal source of drinking water in the vicinity of the Ciba-Geigy Superfund site near Toms River, Ocean County, New Jersey. The presence of earlier identified point sources of organic-compound and, to a lesser extent, metals contamination dt the Ciba-Geigy Toms River Chemical Company Plant has resulted-in severe degradation of ground-water quality and has increased the potentiil for water-supply problems (NUS Corporation, 1988). The point sources of contamination include a manufacturing area, a backfilled-lagoons area, a former fire-prevention training area, several sludge-disposal areas, and a drum-disposal area. A borrow area also is considered a potential source of contamination (Camp Dresser 6 McKee, Inc., 1989). The U.S. Environmental Protection Agency requested that the U.S. Geological Survey evaluate the hydrogeologic conditions in the Kirkwood- Cohansey aquifer system (Zapecza, 1989) and the extent of ground-water contamination on the property of the plant (which includes the Superfund site) and in Winding River Park, which borders the Toms River immediately to the east of the Superfund site (Barton, 1989). This investigation included an electromagnetic-induction survey covering 45 line miles throughout the site and a ground-penetrating-radar survey in part of the borrow area. The quality assurance/quality control plan (QA/QC) for the electromagnetic-induction survey established guidelines for performance, system audits, and data validation, and set control limits for instrument and procedural precision. The QA/QC plan for the groundpenetrating- radar survey sets guidelines for performance and system audits.

New Jersey↗
USGS1989

Aquifer-test analysis of the upper aquifer of the Potomac-Raritan-Magothy aquifer system, Union Beach Borough, Monmouth County, New Jersey

The hydraulic properties of the upper aquifer of the Potomac-Raritan-Magothy aquifer system and of the overlying and underlying confining units were determined from and aquifer test in the vicinity of Union Beach Borough, New Jersey, near Raritan Bay. The April 1986 test included the pumping of 2 test wells for 72 hours at a combined discharge rate of 1,375 gal/min, and the measurement of water levels in 10 observation wells. No lateral recharge boundary in Raritan Bay affected the observed water-level changes. Assuming leaky artesian conditions, the average transmissivity and storage coefficient of the upper aquifer are 7,754 sq ft/day and 0.00044 respectively. The leakance of the combined confining units ranges from 0.000030 to 0.000076/day/ft. On the basis of lithologic samples from a nearby well, the overlying and underlying confining units were assumed to have similar hydraulic properties. By using this assumption, the vertical hydraulic conductivity of the confining units ranges from 0.010 to 0.027 ft/day.

New Jersey↗