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USGS2024

Machine learning approaches to identify lithium concentration in petroleum produced waters

Prices for battery-grade lithium have increased substantially since 2020, which is propelling the search for additional sources of this important element. Battery-grade lithium is predominately recovered from continental brines. Most crude oil and natural gas wells recover briny formation water, which may represent an additional source. Chemical analysis of these waters has been shown to indicate the presence of varying concentrations of lithium and related elements. This paper briefly reviews developments and literature supporting the presence of lithium in petroleum reservoir brines. It also describes the coverage and distribution of lithium data analyses in the United States Geological Survey National Produced Waters Geochemical Database (PWGD). It then addresses the question as to whether a lithium concentration can be accurately predicted using constituents of ion chemistry in produced brines from specific geologic formations. Four machine learning algorithms are employed to classify the commercial potential of lithium in oil field brines using data from oil wells recovering formation water from the Smackover Formation. The calibrated classification models are further applied to new (out-of-sample) data from the Marcellus Formation in the Appalachian Basin. Among the approaches considered, the predictive performance and wider applicability of the gradient boosted tree and the deep neural network models are determined to be the most promising. Finally, we discuss how the calibrated models could be applied to assure the quality of the data reported from chemical laboratory analysis and for imputation when lithium values are missing.

Mineral Economics↗
USGS2016

Water balance monitoring for two bioretention gardens in Omaha, Nebraska, 2011–14

Bioretention gardens are used to help mitigate stormwater runoff in urban settings in an attempt to restore the hydrologic response of the developed land to a natural predevelopment response in which more water is infiltrated rather than routed directly to urban drainage networks. To better understand the performance of bioretention gardens in facilitating infiltration of stormwater in eastern Nebraska, the U.S. Geological Survey, in cooperation with the Douglas County Environmental Services and the Nebraska Environmental Trust, assessed the water balance of two bioretention gardens located in Omaha, Nebraska by monitoring the amount of stormwater entering and leaving the gardens. One garden is on the Douglas County Health Center campus, and the other garden is on the property of the Eastern Nebraska Office on Aging. For the Douglas County Health Center, bioretention garden performance was evaluated on the basis of volume reduction by comparing total inflow volume to total outflow volume. The bioretention garden reduced inflow volumes from a minimum of 33 percent to 100 percent (a complete reduction in inflow volume) depending on the size of the event. Although variable, the percent reduction of the inflow volume tended to decrease with increasing total event rainfall. To assess how well the garden reduces stormwater peak inflow rates, peak inflows were plotted against peak outflows measured at the bioretention garden. Only 39 of the 255 events had any overflow, indicating 100 percent peak reduction in the other events. Of those 39 events having overflow, the mean peak reduction was 63 percent. No overflow events were recorded at the bioretention garden at the Eastern Nebraska Office on Aging; therefore, data were not available for an event-based overflow analysis.Monitoring period summary of the water balance at both bio-retention gardens indicates that most of the stormwater in the bioretention gardens is stored in the subsurface. Evapotranspiration was attributed to a small percentage of the outputs on an annual basis (3 percent at Douglas County Health Center site and 5 percent at Eastern Nebraska Office onAging site), which indicates that vegetative water uptake is not a primary factor in the water budget.

Nebraska↗
USGS2013

Broad timescale forcing and geomorphic mediation of tidal marsh flow and temperature dynamics

Tidal marsh functions are driven by interactions between tides, landscape morphology, and emergent vegetation. Less often considered are the diurnal pattern of tide extremes and seasonal variation of solar insolation in the mix of tidal marsh driver interactions. This work demonstrates how high-frequency hydroperiod and water temperature variability emerges from disparate timescale interactions between tidal marsh morphology, tidal harmonics, and meteorology in the San Francisco Estuary. We compare the tidal and residual flow and temperature response of neighboring tidal sloughs, one possessing natural tidal marsh morphology, and one that is modified for water control. We show that the natural tidal marsh is tuned to lunar phase and produces tidal and fortnight water temperature variability through interacting tide, meteorology, and geomorphic linkages. In contrast, temperature variability is dampened in the modified slough where overbank marsh plain connection is severed by levees. Despite geomorphic differences, a key finding is that both sloughs are heat sinks in summer by latent heat flux-driven residual upstream water advection and sensible and long-wave heat transfer. The precession of a 335-year tidal harmonic assures that these dynamics will shift in the future. Water temperature regulation appears to be a key function of natural tidal sloughs that depends critically on geomorphic mediation. We investigate approaches to untangling the relative influence of sun versus tide on residual water and temperature transport as a function of system morphology. The findings of this study likely have ecological consequences and suggest physical process metrics for tidal marsh restoration performance.

California↗
USGS2021

Riparian forest cover modulates phosphorus storage and nitrogen cycling in agricultural stream sediments

Watershed land cover affects in-stream water quality and sediment nutrient dynamics. The presence of natural land cover in the riparian zone can reduce the negative effects of agricultural land use on water quality; however, literature evaluating the effects of natural riparian land cover on stream sediment nutrient dynamics is scarce. The objective of this study was to assess if stream sediment phosphorus retention and nitrogen removal varies with riparian forest cover in agricultural watersheds. Stream sediment nutrient dynamics from 28 sites with mixed land cover were sampled three times during the growing season. Phosphorus dynamics and nitrification rates did not change considerably throughout the study period. Sediment total phosphorus concentrations and nitrification rates decreased as riparian forest cover increased likely due to a decline in fine, organic material. Denitrification rates were strongly correlated to surface water nitrate concentrations. Denitrification rate and denitrification enzyme activity decreased with an increase in forest cover during the first sampling period only. The first sampling period coincided with the greatest connectivity between the watershed and in-stream processing, indicating that riparian forest cover indirectly decreased denitrification rates by reducing the concentrations of dissolved nutrients entering the stream. This reduction in load may allow the sediment to maintain greater nitrogen removal efficiency, because bacteria are not saturated with nitrogen. Riparian forest cover also appeared to lessen the effect of agriculture in the watershed by decreasing the amount of fine material in the stream, resulting in reduced phosphorus storage in the stream sediment.

Wisconsin↗
USGS2006

Environmental Setting of the Morgan Creek Basin, Maryland, 2002-04

The Morgan Creek Basin is a 31-square-kilometer watershed in Kent County, Maryland on the Delmarva Peninsula. The Delmarva Peninsula covers about 15,500 square kilometers and includes most of the State of Delaware and parts of Maryland and Virginia east of the Chesapeake Bay. The Morgan Creek Basin is one of five sites selected for the study of sources, transport, and fate by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program's: Agricultural Chemicals: Sources, Transport and Fate study team (Agricultural Chemicals Team, ACT). A key component of the study is identifying the natural factors and human influences affecting water quality in the Morgan Creek Basin. The Morgan Creek Basin is in the Coastal Plain Physiographic Province, which is a nearly level seaward-sloping lowland with areas of moderate topographic relief. The study area lies within a well-drained upland region with permeable and porous soils and aquifer sediments. The soils are well suited to most field crops. Agriculture is the principal land use in the Morgan Creek Basin, as well as throughout the entire Delmarva Peninsula. Most agricultural land is used for row crops such as corn, soybeans, and small grains, and slightly less land is used for pasture and hay production involving alfalfa, clover, and various perennial grasses. There are several animal operations in the study area. Farm management practices include fertilizer and herbicide applications, different tillage practices, addition of lime, forested riparian buffers, grassed waterways, and sediment retention ponds. Irrigation in the study area is minimal. The climate of the Morgan Creek Basin is humid and subtropical, with an average annual precipitation of 1.12 meters. Overall annual precipitation is evenly distributed throughout the year, from 76 to 101 millimeters per month; however, the spring and summer (March - September) tend to be slightly wetter than the autumn and winter (October - February). Anomalously high precipitation can occur in summer/early autumn due to occasional hurricanes and tropical storms. Thunderstorms can also produce relatively high localized precipitation over the Morgan Creek Basin during the summer months. Mean daily streamflows for Morgan Creek are highly variable, and somewhat flashy due to the relatively small area of the basin. The long-term median base flow for Morgan Creek is 59 percent of total flow, indicating that total streamflow is most often dominated by a sustained ground-water contribution. Surface runoff accounts for the other 41 percent of the water in total streamflow and dominates during and just after precipitation events. The surficial aquifer in the study area consists of permeable quartz-rich sand and gravel and is underlain by less permeable marine sand, silt, and clay. The depth to water table ranges from less than 0.4 meters below land surface in the floodplain to 12 meters below land surface in upland areas. Ground water generally flows from uplands toward the Morgan Creek floodplain at a variety of depths and time scales. Because the soils and sediments are permeable and porous, some fraction of chemicals applied to the land surface tend to move downward to the water table where they are transported to discharge areas near Morgan Creek.

Open-File Report↗
USGS1955

Ground-water hydraulics - A summary of lectures presented by John G. Ferris at short courses conducted by the Ground Water Branch, part 1, Theory

The objective of the Ground Water Branch is to evaluate the occurrence, availability, and quality of ground water. The science of ground-water hydrology is applied toward attaining that goal. Although many ground-water investigations are of a qualitative nature, quantitative studies are necessarily an integral component of the complete evaluation of occurrence and availability. The worth of an aquifer as a fully developed source of water depends largely on two inherent characteristics: its ability to store, and its ability to transmit water. Furthermore, quantitative knowledge of these characteristics facilitates measurement of hydrologic entities such as recharge, leakage, evapotranspiration, etc. It is recognized that these two characteristics, referred to as the coefficients of storage and transmissibility, generally provide the very foundation on which quantitative studies are constructed. Within the science of ground-water hydrology, ground-water hydraulics methods are applied to determine these constats from field data.

Open-File Report↗
USGS1994

Black Hills hydrology study

The Black Hills area of western South Dakota is a valuable resource center. The area has attracted numerous residents and industries because of the availability of mineral, timber, agricultural, recreational, and water resources. The water resources of the area have been stressed locally by increasing population, periodic drought, and development of other resources. In response to residents' concerns about these stresses on the water resources, the Black Hills Hydrology Study was initiated in 1990 as a cooperative effort among the U.S. Geological Survey, the South Dakota Department of Environment and Natural Resources, and the West Dakota Water Development District. West Dakota represents the various local and county cooperators. This report describes the purpose, scope, approach, and status of the study and presents highlights from the first project data report produced for the study.

Open-File Report↗
USGS1927

Plants as indicators of ground water

Perhaps the most outstanding feature of the flora of the desert is its relation or lack of relation to the water table. On the one hand are the plants which are adapted to extreme economy of water, which depend on the rains that occur at long intervals for their scanty water supplies, and which during prolonged periods of drought maintain themselves in a nearly dormant condition. These plants are known as xerophytes (from Greek roots meaning "dry plant"). On the other hand are the plants that habitually grow where they can send their roots down to the water table or to the capillary fringe immediately overlying the water table and are thus able to obtain a perennial and secure supply of water. These plants have been called phreatophytes. 1 The term is obtained from two Greek roots and means a "well plant." Such a plant is literally a natural well with pumping equipment, lifting water from the zone of saturation.

Water Supply Paper↗
USGS1994

Ground-water quality and geochemistry in Carson and Eagle Valleys, western Nevada and eastern California

Aquifers in Carson and Eagle Valleys are an important source of water for human consumption and agriculture. Concentrations of major constituents in water from the principal aquifers on the west sides of Carson and Eagle Valleys appear to be a result of natural geochemical reactions with minerals derived primarily from plutonic rocks. In general, water from principal aquifers is acceptable for drinking when compared with current (1993) Nevada State drinking-water maximum contaminant level standards. Water was collected and analyzed for all inorganic constituents for which primary or secondary drinking-water standards have been established. About 3 percent of these sites had con- stituents that exceeded one or more primary or secondary drinking-water standards have been established. About 3 percent of these sites had con- stituents that exceeded one or more primary standards and water at about 10 percent of the sites had at least one constituent that surpassed a secondary standard. Arsenic exceeded the standard in water at less than 1 percent of the principal aquifer sites; nitrate surpassed its standard in water at 3 percent of 93 sites. Water from wells in the principal aquifer with high concentrations of nitrate was in areas where septic systems are used; these concentrations indicate that contamination may be entering the wells. Concentrations of naturally occurring radionuclides in water from the principal aquifers, exceed the proposed Federal standards for some constituents, but were not found t be above current (1993) State standards. The uranium concen- trations exceeded the proposed 20 micrograms per liter Federal standard at 10 percent of the sites. Of the sites analyzed for all of the inorganic constituents with primary standards plus uranium, 15 percent exceed one or more established standards. If the proposed 20 micrograms per liter standard for uranium is applied to the sampled sites, then 23 percent would exceed the standard for uranium or some other constituent with a primary drinking water standard. This represents a 50-percent increase in the frequency of exceedance. Almost all water sampled from the principal aquifers exceeds the 300 picocuries per liter proposed standard for radon. Ground-water sampling sites with the highest radon activities in water are most commonly located in the upland aquifers in the Sierra Nevada and in the principal aquifers beneath the west sides of Carson and Eagle Valleys.

Open-File Report↗
USGS2013

The effects of artificial recharge on groundwater levels and water quality in the west hydrogeologic unit of the Warren subbasin, San Bernardino County, California

Between the late 1940s and 1994, groundwater levels in the Warren subbasin, California, declined by as much as 300 feet because pumping exceeded sparse natural recharge. In response, the local water district, Hi-Desert Water District, implemented an artificial-recharge program in early 1995 using imported water from the California State Water Project. Subsequently, the water table rose by as much as 250 feet; however, a study done by the U.S. Geological Survey found that the rising water table entrained high-nitrate septic effluent, which caused nitrate (as nitrogen) concentrations in some wells to increase to more than the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter.. A new artificial-recharge site (site 3) was constructed in 2006 and this study, which started in 2004, was done to address concerns about the possible migration of nitrates in the unsaturated zone. The objectives of this study were to: (1) characterize the hydraulic, chemical, and microbiological properties of the unsaturated zone; (2) monitor changes in water levels and water quality in response to the artificial-recharge program at site 3; (3) determine if nitrates from septic effluent infiltrated through the unsaturated zone to the water table; (4) determine the potential for nitrates within the unsaturated zone to mobilize and contaminate the groundwater as the water table rises in response to artificial recharge; and (5) determine the presence and amount of dissolved organic carbon because of its potential to react with disinfection byproducts during the treatment of water for public use. Two monitoring sites were installed and instrumented with heat-dissipation probes, advanced tensiometers, suction-cup lysimeters, and wells so that the arrival and effects of recharging water from the State Water Project through the 250 to 425 foot-thick unsaturated zone and groundwater system could be closely observed. Monitoring site YVUZ-1 was located between two recharge ponds in the middle of site 3, and YVUZ-2 was located approximately 1,200 feet down-gradient and to the southeast in an area where septic systems have been in use since about 1960. Site YVUZ-3 only went to a depth of 42 feet and was used to sample the upper part of the unsaturated zone near a golf course. Prior to the start of artificial recharge at site 3, nitrate concentrations reported as nitrogen from the soil leachate below YVUZ-1 did not exceed 1.58 milligrams per kilogram. Nitrate-reducing bacteria concentrations of 4,300 most probable number were found at about 220 feet below land surface and at the top of the water table at YVUZ-1. Nitrate concentrations at YVUZ-2 reached a maximum concentration of about 25 milligrams per kilogram between about 100 and 121 feet below land surface; concentrations of nitrate-reducing or denitrifying bacteria were as high as 21,000 most probable number at 36 feet below land surface but did not exceed 40 most probable number below about 150 feet below land surface. Between June 2006 and September 2009, more than 9,800 acre feet of water from the State Water Project was released to site 3 ponds. The infiltration of the recharge water was predominantly vertical with limited lateral spreading to a depth of about 200 feet below land surface at YVUZ-1. Lateral spreading of the recharge water with depth was caused by geologic heterogeneities within the unsaturated zone, and resulted in varied arrival times of the recharge water to the instruments and slower rates of vertical movement with depth. No abrupt changes in soil moisture were observed at YVUZ-2, indicating that the recharge water had not reached that site by September 2009. Water levels from the monitoring wells at both sites and from five production wells nearby showed that the water table rose at a mean rate of about 0.08 feet per day between June 2006 and January 2009. The arrival of the water from the State Water Project caused relatively rapid changes in the stable-isotopic ratios from the lysimeters at YVUZ-1. The estimated average rate of infiltration of the recharge water through the unsaturated zone ranged from 3.7 to 25 feet per day. The recharge water arrived at the monitoring well below the recharge ponds between August 2007 and March 2008; the rate of vertical movement to the monitoring well was between 0.6 and 0.9 feet per day. By September 2008, a production well located 375 feet west of site 3 was producing almost 100 percent infiltrated recharge water. By contrast, the stable-isotope data from the lysimeters at YVUZ-2 showed that the recharge water had not reached this site by September 2009, but that septic effluent in the unsaturated zone likely had mixed with the native pore water to at least 154 feet below land surface. Assuming vertical infiltration, the minimum rate of infiltration of septic effluent since 1960 was about 3 feet per year. The isotopic data from the lysimeters at YVUZ-3 indicated two different sources of water to the upper 43 feet–irrigation-return flow and precipitation. Nitrate concentrations of the water from the State Water Project did not exceed 1 milligram per liter. Prior to artificial recharge, nitrate concentrations of the pore water at YVUZ-1 ranged between 6 to 18.2 milligrams per liter. After the arrival of the recharge water, the nitrate concentrations from the lysimeters and well at YVUZ-1 decreased to less than 1 milligram per liter, with the exception of samples collected at 205.5 feet, which did not exceed 4.12 milligrams per liter. The decrease in nitrate concentrations after artificial recharge indicated that the rising water table did not result in an increase of nitrates below YVUZ-1. At YVUZ-2, nitrate concentrations ranged between 12 to 479 milligrams per liter. The highest nitrate concentrations were at 92 feet below land surface and were almost seven times that of samples collected from a nearby septic tank. Nitrate concentrations from the lysimeter at 273 feet below land surface increased from 6 to almost 58 milligrams per liter after it was saturated by the rising water table in December 2007. These increases could be the result of the mobilization of high-nitrate water from regional sources of septic effluent after saturation, or the result of high-nitrate water present at the top of the water table that may be diluted deeper in the aquifer. Nitrate concentrations in groundwater from five nearby production wells and from both monitoring wells were less than 5 milligrams per liter before artificial recharge started. Nitrate concentrations decreased to less than 3 milligrams per liter in three of the production wells and the monitoring well below the recharge ponds after artificial recharge. Dissolved organic carbon concentrations were measured in the recharge water and groundwater because of the potential for dissolved organic carbon to react with chlorine to form trihalomethanes during the water-treatment process. The dissolved organic carbon concentrations of the recharge water were 3.1 milligrams per liter or less, and dissolved organic carbon concentrations of the groundwater were less than 1 milligram per liter. Even though recharge water was present in some of the wells by September 2008, the concentrations of both dissolved organic carbon and trihalomethane formation potential in the groundwater did not increase. Interpretation of these data suggests that the dissolved organic carbon from the recharge water is altered or metabolized in the unsaturated zone, either by absorption to the grain particles in the soil or by microbiological processes.

California↗
USGS2014

Linkage of the Soil and Water Assessment Tool and the Texas Water Availability Model to simulate the effects of brush management on monthly storage of Canyon Lake, south-central Texas, 1995-2010

The U.S. Geological Survey (USGS), in cooperation with the Texas State Soil and Water Conservation Board, developed and applied an approach to create a linkage between the published upper Guadalupe River Soil Water Assessment Tool (SWAT) brush-management (ashe juniper [ Juniperus ashei ]) model and the full authorization version Guadalupe River Water Availability Model (WAM). The SWAT model was published by the USGS, and the Guadalupe River WAM is available from the Texas Commission on Environmental Quality. The upper Guadalupe River watershed is a substantial component of the Guadalupe River WAM. This report serves in part as documentation of a proof of concept on the feasibility of linking these two water-resources planning models for the purpose of simulating possible increases in water storage in Canyon Lake as a result of different brush-management scenarios. The SWAT-WAM linkage for the upper Guadalupe River is documented with a principal objective to evaluate the distributional characteristics of the monthly water storage of Canyon Lake during selected drought conditions. Focus is on the relative evaluation of select scenarios of large-scale or “extensive” brush management within the upper Guadalupe River watershed. There are six SWAT simulations for the upper Guadalupe River watershed that include a baseline (0-percent management of treatable ashe juniper, the baseline scenario from a previous study in which no percentage of ashe juniper is numerically replaced with grassland) along with five scenarios (extensions of SWAT simulations from a previous study) of 20-, 40-, 60-, 80-, and 100-percent random (numerical) replacement of treatable ashe juniper with grasslands throughout the upper Guadalupe River watershed in south-central Texas. SWAT is a process-based, semidistributed, water-balance model designed to predict the effects of landscape management decisions on water yields. A watershed is subdivided into subbasins, and each subbasin is associated with a single reach on the stream network. In general a WAM, such as the Guadalupe River WAM, provides analysis of generalized water rights in a river and reservoir framework. A WAM accommodates hydrology and water usage through several input files containing water rights, watershed parameters, and naturalized streamflow time series. A WAM is generalized for application to rivers and reservoir systems, and input datasets are uniquely developed for a river basin of concern. The extractions of SWAT output for the five extensive brush-management and baseline scenarios were offset by –21 years and, in general, the results were then mapped to the WAM input-flow file. The offset of –21 years was chosen arbitrarily for technical reasons and means that the period of monthly record 1995–2010 of the upper Guadalupe River SWAT became the synthetic period of monthly record 1974–89, hereinafter 1974–89 (synthetic) period, of the Guadalupe River WAM. The relative (between scenario to baseline) effects of extensive brush-management scenarios by using the SWAT-WAM linkage were evaluated, and two critical intermediate results were total inflow to Canyon Lake from 1995 to 2010 and the monthly storage of Canyon Lake from 1974 to 1989 (synthetic). The first quartile or lower 25th percentile of monthly storage of Canyon Lake for the baseline scenario is 381,000 acre-feet (acre-ft) for the hereinafter 1974–89 (synthetic) period. This lower quartile was chosen for analysis for two critical purposes. First, Canyon Lake is managed with a conservation pool of about 386,200 acre-ft capacity (as recognized by the WAM) and is at or near conservation capacity about 50 percent or more of the time; further, there is intrinsic data censoring that occurs for the monthly storage distribution because Canyon Lake is at or near conservation pool elevation the majority of the time. This intrinsic censoring has the effect of creating a bounded distribution with a left or low-volume tail. Statistical assessment of the brush-management scenarios beginning with the 381,000 acre-ft censoring threshold provides readily interpretable results. Second, the quantification of brush management during periods lacking abundant rainfall, which were defined in this study as months for which Canyon Lake storage was below the 25th percentile for the simulation period, are of substantial interest to water-resource managers and stakeholders in the context of water-supply enhancement. A statistical assessment of the SWAT-WAM linkage for the low-volume tail of the distribution of monthly storage of Canyon Lake is the focus of analysis and interpretation. Drought periods for the analysis are defined as the months (consecutive or not) during which Canyon Lake is below the 25th percentile of storage (381,000 acre-ft) for the baseline scenario. Such months are referred to as being within the “Drought Quartile.” The Drought Quartile is a conceptual and heuristically determined waypoint for the analysis and is not related to any administrative definition of drought by stakeholders or policy makers. The five scenarios and the baseline scenario simulated in the upper Guadalupe River SWAT were all passed through the Guadalupe River WAM by the SWAT-WAM linkage described in this report. A comparison of the mean increase per month in reservoir storage for Canyon Lake conditioned for the Drought Quartile was made. For each of the five brush-management and baseline scenarios, the months with storage below 381,000 acre-ft were extracted. The mean monthly storages during the Drought Quartile were computed for each of the five scenarios and the baseline scenario. The mean of the baseline scenario was 376,458 acre-ft and subsequently was subtracted from the mean monthly storage during the Drought Quartile for each of the five scenarios. The mean monthly offset storages of Canyon Lake during the Drought Quartile were 110 acre-ft (20 percent); 448 acre-ft (40 percent); 754 acre-ft (60 percent); 1,080 acre-ft (80 percent); and 1,090 acre-ft (100 percent). A particular mean was interpreted as follows: the value of 754 acre-ft for the 60-percent brush-management scenario implies that, on average, this scenario indicates an additional 754 acre-ft per month of storage in Canyon Lake relative to the baseline during the Drought Quartile. All of the five scenarios resulted in an increase on average to water supply relative to the baseline scenario during the Drought Quartile through the SWAT-WAM linkage.

Texas↗
USGS2000

Use of biological characteristics of common carp ( Cyprinus carpio ) to indicate exposure to hormonally active agents in selected Minnesota streams, 1999

The presence of hormonally active agents (HAAs) was determined in selected Minnesota streams using biological characteristics (measures of endocrine disruption) of common carp ( Cyprinus carpio ) exposed to wastewater treatment plant (WWTP) effluent and runoff from agricultural and forested land. Four biological characteristics of common carp were used as indicators of HAAs in the streams selected for this study: (1) high concentrations of vitellogenin in male fish and low concentrations in female fish, (2) high or low plasma concentrations of the sex steroid hormones (17β-estradiol and 11-ketotestosterone), (3) low gonado-somatic index (GSI) (gonad weight divided by total body weight multiplied by 100) values, and (4) abnormal gonad histopathology (high percent of atretic oocytes in female ovaries and high percent ceroid/lipofuscin tissue in male or female gonads). The study design was a paired site approach targeting sites downstream and upstream of WWTP discharges on different streams. Male (221 individuals) and female (201 individuals) common carp were collected using electrofishing techniques from seven streams with sites at two locations (upstream and downstream of WWTPs), and eight sites located downstream of WWTPs with no upstream-paired sites. Samples were collected between August 3 and September 13, 1999. The presence of HAAs in selected Minnesota streams was indicated by biological characteristics in common carp. Biological characteristics used in this study identified WWTP effluent as a potential source of HAAs. Additionally, fish located at sites upstream of WWTP effluent primarily draining agricultural land show indications of HAAs, which may be the result of agricultural runoff or other sources of HAAs. There was variability among all sites and among sites within each site group. Differences among sites may be due to differences in water chemistry or fish exposure time. Natural variation in the biological characteristics may account for some of the differences observed in this study. This study and others indicate the presence of HAAs in surface water and the potential signs of endocrine disruption in resident fish populations. Detailed controlled studies could confirm the effects of particular chemicals such as pesticides or components of WWTPs on fish reproduction and population structure.

Minnesota↗
USGS1965

Hydrology of the Little Plover River basin, Portage County, Wisconsin, and the effects of water resource development

The Little Plover River basin is in the sand-plain area of central Wisconsin. The basin and the surrounding sand-plain area provide a good fish and wildlife habitat and is a popular locale for sport fishing. Good yields may be obtained in the area from irrigated crops, and the irrigated acreage has been increasing rapidly in recent years. Sportsmen and conservationists are concerned about the effects of increased development of the water resources on the streams as trout habitat. In the past, many political and legal conflicts among water users have arisen from erroneous opinions as to the behavior of water. Many of these conflicts would be diminished or eliminated if the participants were cognizant of fundamental hydrologic principles. This study was made to demonstrate the extent and nature of the interrelation of ground water and surface water and the fundamental hydrologic principles governing water movement. The study was also made to determine the hydrologic changes that might occur following development, to provide information that might be used as a basis for planning water development, and for drafting legislation that recognizes the relation between ground water and surface water. Water has been developed in the Little Plover River basin for industry, for domestic and stock supplies, and for irrigation. Irrigated acreage is increasing in the area, and the use of water for irrigation may alter the hydrology of the basin somewhat. About 4,000-4,500 acres of land within the basin, or 50-60 percent of the basin area, is suitable for irrigated farming, but probably no more than 2,500 acres will be under irrigation in any one year, unless present crop-rotation practices are changed. Most of the Little Plover River basin is underlain by from 40 to 100 feet of glacial outwash consisting of highly permeable sand and gravel. The glacial outwash is the main aquifer in the area and is capable of yielding large quantities of water to wells. An aquifer test in the area indicated that the coefficient of transmissibility of the glacial outwash is about 140,000 gallons per day per foot. The specific yield of the outwash is about 20 percent, as determined from water-level and streamfiow data. Morainal deposits occur locally with the glacial outwash. These deposits transmit water readily and do not form barriers to ground water in the outwash. Relatively impermeable crystalline rocks underlie the glacial deposits, and a sandstone ridge of low permeability impedes the movement of ground water from the basin by underflow. The glacial outwash and morainal deposits are recharged by infiltration of 9-10 inches of the 31 inches of precipitation that falls on the area in an average year. If it is not withdrawn by wells for consumptive use or by phreatophytes, water that infiltrates the sand and gravel discharges later into the Little Plover River. This ground-water discharge constitutes 90-95 percent of the total flow of the Little Plover River. Annual evapotranspiration varies considerably, but generally ranges from 2 to 8 inches less than the potential evapotranspiration of 24 inches. Consumptive use of irrigation water averages about 4 inches per year. Most of the water pumped from wells otherwise would be discharged to the stream, and consumptive use of irrigation water will deplete streamflow by the amount of evapotranspiration. Pumping wells have little effect on the water level in the highly permeable sand and gravel. Significant interference between wells would occur only if large capacity wells were within a few tens of feet of each other. Ground water and surface water are closely interrelated in the sand-plain area and ground-water withdrawals near the Little Plover River may cause a measurable streamflow depletion. In a test, a well that was pumping about 1,120 gpm (gallons per minute) and that was 300 feet from the stream derived about 30 percent of its flow from the stream after 3 days of pumping. For this study, the effects of increased ground-water development were evaluated from a hypothetical development schedule, for which it was assumed that 500 acres were irrigated the first year and that an additional 50 acres were irrigated in each succeeding year for 10 years. It also was assumed that the average annual consumptive-use requirement for irrigation water would be one- third of an acre-foot per acre. Calculations indicate that the maximum monthly rate of depletion due to the consumptive use of 4 inches of ground water per year on 500 acres would be about 0.4 cfs (cubic feet per second) the first year and 0.5 cfs after 10 years of pumping. Other computations indicate that the maximum monthly rate of depletion due to irrigating 500 acres the first year and 50 additional acres each year for 10 years would be about 0.8 cfs. Maximum depletion would occur during the summer months, concurrent with the irrigation withdrawals. Because of the close interrelation between ground and surface water, surface- water withdrawals will cause an increased inflow of ground water to the stream and a decline in ground-water levels near the stream. These effects were demonstrated by pumping from the stream. After 29 hours of pumping, a depletion of 1,120 gpm at a site 7,000 feet downstream was about 200 gpm less than the diversion at the pump. Most of the 200 gpm was supplied from the stream-banks, and ground-water levels near the stream declined as much as 0.3 foot. Computations indicated that ground-water inflow, following a streamflow diver- sion that lowered the stage 0.15 foot, would be 0.14 cfs after 5 days and 0.06 cfs after 30 days. The demonstration of the quantitative relation between ground water and surface water, as given by this study, should provide a sound basis for planning water development to minimize conflicts of interest. The demonstrations also should provide a basis for drafting legislation that recognizes the interrelation of ground water and surface water. Because the geology and the hydrology are relatively uniform throughout the sand plains, many of the methods and hydrologic values determined for this detailed study of the Little Plover River basin may be applied to other basins in the sand-plain area.

Wisconsin↗
USGS1967

Results of the second phase of the drought-disaster test-drilling program near Morristown, N.J.

The continued drought in northeastern New Jersey through the summer of 1966 with its attendant water-supply problems resulted in an extension of the drought-disaster test-drilling program originally requested by the Office of Emergency Planning on August 30, 1965. Authorization to continue test drilling was fiven by the Office of Emergency Planning on September 26, 1966, with the stipulation that all field work be complete by January 31, 1977. Contractural costs were paid by the Office of Emergency Planning, whereas personnel costs were shared by the U.S. Geological Survey and the New Jersey Department of Conservation and Economic Development, Division of Water Policy and Supply. The work undertaken in 1965 by the Geological Survey was "...to preform the necessary drilling and testing of wells to identify the extent and nature of a reserve ground-water source in the vicinity of the Passaic River near the northern New Jersey metropolitan area." Results of this first phase were made available in the fall of 1966 in Water Resources Circular 16 of the New Jersey Department of Conservation and Economic Development. Three of the five areas tested (figure 1)--two in Parsippany-Troy Hills Township (areas 2 and 4) and one in East Hanover Township (area 1), Morris County--proved capable of providing an aggregate sustained yield of 7.5 million gallons daily (mgd) from wells constructed in sand and gravel deposits. Because significant supplies of ground water for emergency use were located in the first phase of the exploratory test-drilling program, it was though desirable to extend the originally planned studies so as to obtain maximum practicable information on emergency supplies. During this second phase of the investigation, drilling was conducted in 16 sites in Chatham, Madison, and Florham Park Boroughs and in Hanover and East Hanover Townships, Morris County. (See figure 2.) The drilling in Hanover and East Hanover Townships, and part of the drilling done in Florham Park was to explore the availability of large undeveloped ground-water supplies. Drilling in Chatham, Madison, and Florham Park Boroughs was done primarily to determine the extent and continuity of buried valley-fill aquifers, so that a full evaluation of the effects of pumpage from other areas on these already heavily pumped areas could be made. In addition, it was anticipated that the drilling could help in defining the feasibility of artificial recharge of the heavily pumped areas and in the determination of the prospective method of recharge and points of emplacement. Arrangements for easements with landowners, preparation of specifications for well drilling and seismic work, and supervision of well drilling and seismic contracts were all performed by the New Jersey District, Water Resources Division of the Geological Survey. Prior to the test drilling, seismic exploration under contract with Alpine Geophysical Associates of Norwood, N. J. was conducted at five locations in the Chatham-Madison-Florham Park area and at one place in Parsippany-Troy Hills Township. The seismic work was done to determine the most favorable location for a test well at several potential test-well sites and to help in the interpretation of subsurface geology between test sites. Contracts for the drilling of the test holes were awarded during November and drilling commences on November 30. Kaye Well drilling, Inc. of Jackson, N. J. was the recipient of a contract for eight of the test holes, and a second contract was awarded to Rinbrand Well Drilling Co., Inc. of Glen Rock, N. J.--also for eight test holes. Acknowledgment is due to the many public officials of Chatham, Madison, Florham Park, Morristown, and East Hanover Township as well as officials of the Braidburn Corporation and Esso Research and Engineering Co., who cooperated by making their lands available for exploration.

New Jersey↗
USGS2008

Low-Level detections of halogenated volatile organic compounds in groundwater: Use in vulnerability assessments

Concentrations of halogenated volatile organic compounds (VOCs) were determined by gas chromatography (GC) with an electron-capture detector (GC-ECD) and by gas chromatography with mass spectrometry (GC-MS) in 109 groundwater samples from five study areas in the United States. In each case, the untreated water sample was used for drinking-water purposes or was from a monitoring well in an area near a drinking-water source. The minimum detection levels (MDLs) for 25 VOCs that were identified in GC-ECD chromatograms, typically, were two to more than four orders of magnitude below the GC-MS MDLs. At least six halogenated VOCs were detected in all of the water samples analyzed by GC-ECD, although one or more VOCs were detected in only 43% of the water samples analyzed by GC-MS. In nearly all of the samples, VOC concentrations were very low and presented no known health risk. Most of the low-level VOC detections indicated post-1940s recharge, or mixtures of recharge that contained a fraction of post-1940s water. Concentrations of selected halogenated VOCs in groundwater from natural and anthropogenic atmospheric sources were estimated and used to recognize water samples that are being impacted by nonatmospheric sources. A classification is presented to perform vulnerability assessments at the scale of individual wells using the number of halogenated VOC detections and total dissolved VOC concentrations in samples of untreated drinking water. The low-level VOC detections are useful in vulnerability assessments, particularly for samples in which no VOCs are detected by GC-MS analysis.

Journal of Hydrologic Engineering↗
USGS2009

An Excel Workbook for Identifying Redox Processes in Ground Water

The reduction/oxidation (redox) condition of ground water affects the concentration, transport, and fate of many anthropogenic and natural contaminants. The redox state of a ground-water sample is defined by the dominant type of reduction/oxidation reaction, or redox process, occurring in the sample, as inferred from water-quality data. However, because of the difficulty in defining and applying a systematic redox framework to samples from diverse hydrogeologic settings, many regional water-quality investigations do not attempt to determine the predominant redox process in ground water. Recently, McMahon and Chapelle (2008) devised a redox framework that was applied to a large number of samples from 15 principal aquifer systems in the United States to examine the effect of redox processes on water quality. This framework was expanded by Chapelle and others (in press) to use measured sulfide data to differentiate between iron(III)- and sulfate-reducing conditions. These investigations showed that a systematic approach to characterize redox conditions in ground water could be applied to datasets from diverse hydrogeologic settings using water-quality data routinely collected in regional water-quality investigations. This report describes the Microsoft Excel workbook, RedoxAssignment_McMahon&Chapelle.xls, that assigns the predominant redox process to samples using the framework created by McMahon and Chapelle (2008) and expanded by Chapelle and others (in press). Assignment of redox conditions is based on concentrations of dissolved oxygen (O2), nitrate (NO3-), manganese (Mn2+), iron (Fe2+), sulfate (SO42-), and sulfide (sum of dihydrogen sulfide [aqueous H2S], hydrogen sulfide [HS-], and sulfide [S2-]). The logical arguments for assigning the predominant redox process to each sample are performed by a program written in Microsoft Visual Basic for Applications (VBA). The program is called from buttons on the main worksheet. The number of samples that can be analyzed is only limited by the number of rows in Excel (65,536 for Excel 2003 and XP; and 1,048,576 for Excel 2007), and is therefore appropriate for large datasets.

Open-File Report↗
USGS1989

Hydrologic data for the Big Spring basin, Clayton County, Iowa, water year 1988

Hydrologic data was collected during the 1988 water year in cooperation with the Iowa Department of Natural Resources Geological Survey Bureau in the Big Spring ground-water basin located in Clayton County, Iowa. Information on precipitation, streams, and ground water was collected in the basin. Total rainfall at Big Spring was 24.08 inches. The greatest monthly rainfall was in September. Calcium and sulfate were the predominant ions in the rain and the median ammonia and nitrate concentrations as nitrogen were 0.40 and 0.37 mg/L (milligrams per liter), respectively. Stream discharge, water temperature, specific conductance, and pH were monitored continuously and monthly water-quality samples were collected at three sites in the basin. In the streams, water temperature and pH vary diurnally and are greatest during the day. Specific conductance varies inversely with water temperature and pH. The predominant ions in the streams were calcium, magnesium, and bicarbonate. Nitrate plus nitrite as nitrogen concentrations ranged from 0.5 to 15 mg/L. Pesticide concentrations ranged from less than 0.10 µ g/L (micrograms per liter) to 0.72 µ g/L. Atrazine was detected in 12 of 13 stream samples and cyanazine was detected in 4 of 13 samples. The daily mean temperature of the water in Big Spring ranged from 9.7 to 10.6 degrees Celsius, the daily mean specific conductance ranged from 698 to 735 microsiemens per centimeter at 25 degrees Celsius, and the daily median pH ranged from 6.7 to 7.1. Calcium, magnesium, and bicarbonate were the predominant ions in solution. Nitrate plus nitrite as nitrogen concentrations ranged from 7.5 to 11 mg/L. Atrazine was the only pesticide detected in the monthly samples from Big Spring. Atrazine concentrations were greater than the detection limit in six of seven samples and ranged from less than 0.10 to 0.26 µ g/L. During a baseflow seepage study, June 28 and 29, the discharge lost by streams in the basin was 5.57 cubic feet per second and the dissolved nitrogen load lost was 0.19 tons per day. The discharge and total dissolved nitrogen leaving the basin in streams was 2.93 cubic feet per second and 0.02 tons per day, respectively.

Iowa↗
USGS2008

Potentiometric Surface in the Sparta-Memphis Aquifer of the Mississippi Embayment, Spring 2007

The most widely used aquifer for industry and public supply in the Mississippi embayment in Arkansas, Louisiana, Mississippi, and Tennessee is the Sparta-Memphis aquifer. Decades of pumping from the Sparta-Memphis aquifer have affected ground-water levels throughout the Mississippi embayment. Regional assessments of water-level data from the aquifer are important to document regional water-level conditions and to develop a broad view of the effects of ground-water development and management on the sustainability and availability of the region's water supply. This information is useful to identify areas of water-level declines, identify cumulative areal declines that may cross State boundaries, evaluate the effectiveness of ground-water management strategies practiced in different States, and identify areas with substantial data gaps that may preclude effective management of ground-water resources. A ground-water flow model of the northern Mississippi embayment is being developed by the Mississippi Embayment Regional Aquifer Study (MERAS) to aid in answering questions about ground-water availability and sustainability. The MERAS study area covers parts of eight states including Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee and covers approximately 70,000 square miles. The U.S. Geological Survey (USGS) and the Mississippi Department of Environmental Quality Office of Land and Water Resources measured water levels in wells completed in the Sparta-Memphis aquifer in the spring of 2007 to assist in the MERAS model calibration and to document regional water-level conditions. Measurements by the USGS and the Mississippi Department of Environmental Quality Office of Land and Water Resources were done in cooperation with the Arkansas Natural Resources Commission; the Arkansas Geological Survey; Memphis Light, Gas and Water; Shelby County, Tennessee; and the city of Germantown, Tennessee. In 2005, total water use from the Sparta-Memphis aquifer in the Mississippi embayment was about 540 million gallons per day (Mgal/d). Water use from the Sparta-Memphis aquifer was about 170 Mgal/d in Arkansas, about 68 Mgal/d in Louisiana, about 97 Mgal/d in Mississippi, and about 205 Mgal/d in Tennessee. The author acknowledges, with great appreciation, the efforts of the personnel in the U.S. Geological Survey Water Science Centers of Arkansas, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee, and the Mississippi Department of Environmental Quality Office of Land and Water Resources that participated in the planning, water-level measurement, data evaluation, and review of the potentiometric-surface map. Without the contribution of data and the technical assistance of their staffs, this report would not have been completed.

Scientific Investigations Map↗