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Techniques for detecting effects of urban and rural land-use practices on stream-water chemistry in selected watersheds in Texas, Minnesota,and Illinois

Although considerable effort has been expended during the past two decades to control nonpoint-source contamination of streams and lakes in urban and rural watersheds, little has been published on the effectiveness of various management practices at the watershed scale. This report presents a discussion of several parametric and nonparametric statistical techniques for detecting changes in water-chemistry data. The need for reducing the influence of natural variability was recognized and accomplished through the use of regression equations. Traditional analyses have focused on fixed-frequency instantaneous concentration data; this report describes the use of storm load data as an alternative. Selected statistical techniques were applied to three urban watersheds in Texas and Minnesota and three rural watersheds in Illinois. For the urban watersheds, single- and paired-site data-collection strategies were considered. The paired-site strategy was much more effective than the singlesite strategy for detecting changes. Analysis of storm load regression residuals demonstrated the potential utility of regressions for variability reduction. For the rural watersheds, none of the selected techniques were effective at identifying changes, primarily due to a small degree of management-practice implementation, potential errors introduced through the estimation of storm load, and small sample sizes. A Monte Carlo sensitivity analysis was used to determine the percent change in water chemistry that could be detected for each watershed. In most instances, the use of regressions improved the ability to detect changes.

Illinois, Minnesota, Texas↗

Snowpack chemistry at selected sites in Colorado and New Mexico during winter 1999-2000

Snowpacks at two high-elevation (> 3,000 m) sampling sites near McPhee and Sanchez Reservoirs in southern Colorado were selected to collect representative samples of atmospheric deposition to the surrounding watersheds during winter 1999-2000. In February 2000, annual snowpacks at two sites were sampled to determine concentrations of nitrate and sulfate; concentrations of the trace elements arsenic, mercury, and selenium; and the sulfur isotope ratios that result from atmospheric deposition to the area. Snowpack chemistry data at the two sites sampled in 1999-2000 are compared to 1993-99 averages at 10 other snow-sampling sites in Colorado and New Mexico that generally are downwind of the Four Corners area of the southwestern United States. Although concentrations of ammonium and nitrate in the 1999-2000 snowpacks were fairly typical compared to averages established at nearby sites in southern Colorado and northern New Mexico, chloride and sulfate concentrations were below the 1993-99 average, while arsenic, mercury, and selenium in snow were much below the 1993-99 average. However, very similar sulfur-isotope ratios (that are not a function of precipitation amounts) deposited in snowpacks at the nearby sites indicate the snowpack chemistries at the new sampling locations near McPhee and Sanchez reservoirs were affected by similar sources of sulfate. Representative samples of coal burned during the 1999-2000 snowfall season at three power plants near Four Corners also were analyzed for sulfur content and trace elements. Results from separate, independent laboratories show similar concentrations and provide an initial baseline that will be used for general comparisons of coal chemistry to snowpack chemistry.

Colorado, New Mexico↗

Rocky Mountain Snowpack Chemistry at Selected Sites, 2002

During spring 2002, the chemical composition of annual snowpacks in the Rocky Mountain region of the Western United States was analyzed. Snow samples were collected at 75 geographically distributed sites extending from New Mexico to Montana. Near the end of the 2002 snowfall season, the snow-water equivalent (SWE) in annual snowpacks sampled generally was below average in most of the region. Regional patterns in the concentrations of major ions (including ammonium, nitrate, and sulfate), mercury, and stable sulfur isotope ratios are presented. The 2002 snowpack chemistry in the region differed from the previous year. Snowpack ammonium concentrations were higher at 66 percent of sites in Montana compared to concentrations in the 2001 snowpack but were lower at 74 percent of sites in Wyoming, Colorado, and New Mexico. Nitrate was lower at all Montana sites and lower at all but one Wyoming site; nitrate was higher at all but two Colorado sites and higher at all New Mexico sites. Sulfate was lower across the region at 77 percent of sites. The range of mercury concentrations for the region was similar to those of 2001 but showed more variability than ammonium, nitrate, and sulfate concentrations. Concentrations of stable sulfur isotope ratios exhibited a strong regional pattern with values increasing northward from southern Colorado to northern Colorado and Wyoming.

Open-File Report↗

Rocky Mountain snowpack chemistry at selected sites for 2001

Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey, in cooperation with the National Park Service, U.S. Department of Agriculture Forest Service, and other agencies, to more thoroughly determine the chemical composition of precipitation and to identify sources of atmospherically deposited contaminants in a network of high-elevation sites. Samples of seasonal snowpacks at 57 geographically distributed sites, in a regional network from New Mexico to Montana, were collected and analyzed for major ions (including ammonium, nitrate, and sulfate), alkalinity, and dissolved organic carbon during 2001. Sites selected in this report have been sampled annually since 1993, enabling identification of increases or decreases in chemical concentrations from year to year. Spatial patterns in snowpack-chemical data for concentrations of ammonium, nitrate, and sulfate indicate that concentrations of these acid precursors in less developed areas of the region are lower than concentrations in the heavily developed areas. Results for the 2001 snowpack-chemistry analyses, however, indicate increases in concentrations of ammonium and nitrate in particular at sites where past concentrations typically were lower. Since 1993, concentrations of nitrate and sulfate were highest from snowpack samples in northern Colorado that were collected from sites adjacent to the Denver metropolitan area to the east and the coal-fired powerplants to the west. In 2001, relatively high concentrations of nitrate (12.3 to 23.0 microequivalents per liter (µeq/L) and sulfate (7.7 to 12.5 µeq/L) were detected in Montana and Wyoming. Ammonium concentrations were highest in north-central Colorado (14.5 to 16.9 µeq/L) and southwestern Montana (12.8 to 14.2 µeq/L).

Rocky Mountains↗

Effects of storm paths on precipitation chemistry, and variations of within-storm chemistry during selected storms in central Massachusetts, 1986-87

Samples of precipitation from 31 storms were collected from October 1986 through December 1987 at a site near Quabbin Reservoir in central Massachusetts and were analyzed for pH, specific conductance, and concentrations of common chemical constituent. Twenty-four storms followed a conti- nental path west of the Appalachian Mountains. The remaining seven storms followed a coastal path east of the Appalachian Mountains along the Atlantic Coast. Precipitation from the continental storms was more acidic than precipitation from the coastal storms according to a nonparametric statistical com- parison. Because the continental storms had less volume, the loads of hydrogen ions and other common chemical constituents from both groups were not statistically different. The variability of within- storm precipitation chemistry was evaluated for 8 of the 31 storms. Seven of the storms showed evidence of suspended-particulate removal at levels between the cloud layer and the land surface during their early stages. The remaining storm, also the most acidic, showed evidence of suspended- particulate removal within the cloud layer as indicated by a relatively constant pH throughout the storm. Surface-air concentrations of sulfur dioxide and nitrogen dioxide before, during, and after each of the eight storms were compared to within-storm values of pH and precipitation. Seven of the storms were accompanied by decreased atmospheric concen- trations of both sulfur dioxide and nitrogen dioxide in the early stages of the storm. For three of the storms, atmospheric concentrations of sulfur dioxide and nitrogen dioxide were higher during the 24-hour period after the storm than the 24-hour period pre- ceding the storm. Particulates in precipitation samples were analyzed for three storms. Biotite was the predominant mineral in two of the storms. Other minerals detected were garnet, quartz, gypsum, hematite, epidote, ilmenite, eggonite, halite, rutile, and organic ash.

Water-Resources Investigations Report↗

Snowpack chemistry at selected sites in northwestern Colorado during spring 1995

Samples of the alpine and subalpine snowpack were collected in and near the headwater basins of the Yampa River in northwestern Colorado during maximum annual accumulation of snowpack in spring 1995. Sampling protocol at seven selected sites at more than 2,500 meters above sea level divided the snowpack into two distinct strata to enable separate chemical analyses of upper and lower layers of the annual snow cover. These two layers correspond to the early snow season beginning in September until December 12, 1994, and the remainder of the season from January 1 until the sampling date in spring 1995. At one site these two strata were resampled at closely spaced intervals defining substrata to observe variance within the two strata dividing the snow season. Analytical results of snowpack chemistry are presented in support of investigations of seasonal effects on ion concentrations in the snowpack. Chemical concentrations of major anions and cations, dissolved organic carbon, and alkalinity; measured pH; calculated charge balance between anions and cations; the stable-sulfur isotope ratio (34S/32S); and summary statistics of chemical concentrations are tabulated. Sampling sites are plotted on a map of the area. Spatial distributions of the concentrations of the hydrogen, nitrate, and sulfate ions and stable- sulfur isotope ratios also are mapped. Several unusual, late-season, snowfall events occurred during April and May of 1995 after the snowpack was sampled at most of the seven sites in the study area. Consequently, a considerable fraction of the total annual snowpack was not sampled. At one site, the full snowpack was sampled again in June, after the late-spring storms, for comparison to the chemistry of the snowpack sampled earlier in April. Precipitation chemistry from a National Atmospheric Deposition Program (NADP) collector located near the site is presented for comparison of the chemistry of the late-season snow to that of the typical annual snowpack season.

Open-File Report↗

Stratigraphic section and selected semiquantitative chemistry, Meade Peak phosphatic shale member of Permian Phosphoria Formation, central part of Rasmussen Ridge, Caribou County, Idaho

The U.S. Geological Survey (USGS) has studied the Permian Phosphoria Formation in southeastern Idaho and the entire Western U.S. Phosphate Field throughout much of the twentieth century. In response to a request by the U.S. Bureau of Land Management, a new series of resource, geological, and geoenvironmental studies was undertaken by the USGS in 1998. To accomplish these studies, the USGS has formed cooperative research relationships with two Federal agencies, the Bureau of Land Management and the U.S. Forest Service, tasked with land management and resource conservation on public lands; and with five private companies currently leasing or developing phosphate resources in southeastern Idaho. The companies are Agrium U.S. Inc. (Rasmussen Ridge mine) , Astaris LLC (Dry Valley mine), Rhodia Inc. (Wooley Valley mine, inactive), J.R. Simplot Company (Smoky Canyon mine), and Monsanto Co. (Enoch Valley mine). Some of the mineralogical research associated with this project is supported through a cooperative agreement with the Department of Geology and Geological Enginee ring, University of Idaho. Present studies consist of integrated, multidisciplinary research directed toward (1) resource and reserve estimations of phosphate in selected 7.5-minute quadrangles; (2) elemental residence, mineralogical and petrochemical characteristics; (3) mobilization and reaction pathways, transport, and fate of potentially toxic elements associated with the occurrence, development, and societal use of phosphate; (4) geophysical signatures; and (5) improving the understanding of deposit origin. Because raw data acquired during the project will require time to interpret, the data are released in open-file reports for prompt availability to other workers. Open-file reports associated with this series of studies are submitted to each of the Federal and industry cooperators for comment; however, the USGS is solely responsible for the data contained in the reports.

Idaho↗

Hydrology and chemistry of selected prairie wetlands in the Cottonwood Lake area, Stutsman County, North Dakota, 1979-82

The relation of hydrologic setting and temporal variability in hydrology to nutrient content and geochemical characteristics of a group of prairie wetlands and adjacent ground water was studied during the period 1979-82. Although data were collected from many wetlands and wells at the study site, emphasis in this report primarily is on four wetlands two seasonal and two semipermanent and four wells contiguous to them along a hydrologic section. The seasonal wetlands, T8 and T3, contained water only for a few weeks to months after filling in spring and early summer; both were completely dry by August. The semipermanent wetlands, PI and P8, contained water throughout each year and were ice covered in winter. One wetland, T8, recharges ground water. Wetlands PI and P8 are in areas of ground-water discharge. None of the wetlands received water by channelized surface-water inlets. Only wetland P8 had a channelized surface-water outlet. Ground-water-level data showed that high points of the water table did not always occur beneath land-surface highs. Reversals of ground-water flow occurred occasionally between two of the wetlands, T3 and PI. Significant differences existed in the chemical composition of the wetlands based on their hydrologic setting. In general, the dominant cation and anion in the wetlands were potassium and bicarbonate in wetland T8, calcium and sulfate in wetland T3, magnesium and sulfate in wetland PI, and magnesium and bicarbonate in wetland P8. Significant seasonal differences existed in the water chemistry of the wetlands in ground-water discharge areas. Water in three of the wetlands, T3, Pi, and P8, was most dilute while they filled in spring after icemelt. Concentration increased during the open-water period, and two of the wetlands, PI and P8, became most concentrated under ice cover. Concentrations of total phosphorus and total nitrogen were greatest in wetlands in areas of ground-water recharge and least in wetlands in areas of ground-water discharge. Differences in the chemistry of water from wells in the adjacent ground water resulted primarily from the positions of the wells in the ground-water flow system. The chemical type of water from well 12, which was located in a ground-water recharge area, was calcium sodium bicarbonate. Water from well 4, located downgradient from wetland T8, and from well 16, located downgradient from wetland PI, typically was a calcium sulfate type. Water from well 13, located between wetlands T3 and PI in an area of changing ground-water flow directions, was a magnesium sulfate type. Data from this study show that an understanding of hydrologic conditions is important in the interpretation of the water chemistry of wetlands in the study area.

Professional Paper↗

The geology, botany and chemistry of selected peat-forming environments from temperate and tropical latitudes

Peat has been studied in several geologic settings: (1) glaciated terrain in cold temperate Maine and Minnesota, U.S.A.; (2) an island in the Atlantic Ocean off the coast of Maine, where sea level is rising; (3) the warm temperate U.S. Atlantic and Gulf Coastal Plains, where sea level has changed often; and (4) the tropical coast of Sarawak, Malaysia, and the tropical delta of the Batang Hari River, Sumatra, Indonesia. Most of these deposits are domed (ombrotrophic or partly ombrotrophic) bogs in which peat accumulation continued above the surface of the surrounding soil. However, the bogs of the U.S. Atlantic and Gulf Coastal Plains are comparatively not as domed, and many have almost level surfaces. In some bogs, aquatic or semi-aquatic plant materials accumulated, replaced water in the depressions, and formed a surface on which marsh or swamp vegetation could subsequently live, die, and accumulate. In others, the plant materials accumulated initially on level silt or sand surfaces supporting marshes or swamps. As the peat dome formed, plants growing on it changed from luxuriant ones near the base of the dome, where nutrients were brought into the bog by surface and ground water, to stunted ones at the top of the dome, where the raised bogs are fed by nutrient-poor precipitation. The physical and chemical changes that take place in the sequence of environments from the pond stage of deposit development, through the grassy marsh stage, through the forested swamp stage, and finally through the heath dome stage can be measured in terms of acidity and ash, volatile matter, carbon, hydrogen, nitrogen, sulfur and oxygen contents, as well as in the kind and distribution of trace elements. The organic and inorganic contents of the deposits relate to geomorphology, and geomorphology relates to their settings. As models of coal formation, some domed peat deposits may help in solving problems of distribution and character of ancient coal beds. But clearly not all peat deposits are precursors of coal. Most Holocene peat deposits are subject to destruction by erosion, fire and decomposition through microbial and chemical oxidation before burial. The best environments for coal precursors have biomass accumulation, a continuously rising water table within the mass, and minimum influx of clay and silt until preservation by burial. The most suitable settings for future economic coal deposits are domed bogs that accumulate thick, widespread peat having low ash and low sulfur contents. The ombrotrophic peat deposits of tropical Sarawak and Sumatra are thick and extensive, contain low-ash and low-sulfur peat, and have high heating values. They are considered to be the best tropical coal analogs because of their extent and chances of preservation; the base of the peat is below adjacent river levels, and chemical and structural conditions are favorable for accumulation.

International Journal of Coal Geology↗

Chemistry of selected high-elevation lakes in seven national parks in the western United States

A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky Mountain National Park) were very dilute; medianspecific conductance ranged from 4.4 to 12.2 μS cm -1 andmedian alkalinity concentrations ranged from 32.2 to 72.9 μeqL -1 . Specific conductances and alkalinity concentrations were substantially higher in lakes in the central and northernRocky Mountains parks (Grand Teton, Yellowstone, and GlacierNational Parks), probably due to the prevalence of more reactivebedrock types. Regional patterns in lake concentrations of NO 3 and SO 4 were similar to regional patterns in NO 3 and SO 4 concentrations in precipitation, suggestingthat the lakes are showing a response to atmospheric deposition.Concentrations of NO 3 were particularly high in Rocky Mountain National Park, where some ecosystems appear to be undergoing nitrogen saturation.

Water, Air, and Soil Pollution: Focus↗

Aquatic Communities and Selected Water Chemistry in St. Vrain Creek near the City of Longmont, Colorado, Wastewater-Treatment Plant, 2005 and 2006

In 2005, the U.S. Geological Survey and the City of Longmont, Colo., began a study to document chemical characteristics of St. Vrain Creek that had previously been unavailable either due to high cost of analysis or lack of analytical capability. Stream samples were collected at seven sites on St. Vrain Creek during the spring of 2005 and 2006 for analysis of wastewater compounds. A Lagrangian-sampling design was followed during each sampling event, and time-of-travel studies were conducted just prior to each sampling event to determine appropriate sampling times for the synoptic. In addition, semipermeable membrane devices, passive samplers that concentrate hydrophobic organic chemicals, were installed at six sites during the spring of 2005 and 2006 for approximately 4 weeks. After retrieval, contaminant residues concentrated in the semipermeable membrane devices were recovered and used in a toxicity assay that provided a screen for aryl hydrocarbon receptor type compounds, including polycyclic aromatic hydrocarbons, polychlorinated biphenyls, dioxins, and furans. In addition, the U.S. Geological Survey summarized information on macroinvertebrate and fish communities known from St. Vrain Creek dating back to the early 1900s in order to assess their utility in evaluating wastewater-treatment plant upgrades and habitat improvement projects. Unfortunately, because of inconsistencies in data collection these data cannot be used as intended; however, they are useful for understanding to some degree gross patterns in fish species distribution, but less so for macroinvertebrates.

Data Series↗

Rocky Mountain Snowpack Chemistry at Selected Sites, 2004

During spring 2004, the U.S. Geological Survey in cooperation with the National Park Service and the U.S. Department of Agriculture, Forest Service collected and analyzed snowpack samples for 65 sites in the Rocky Mountain region from New Mexico to Montana. Snowpacks were sampled from late February through early April and generally had well-below-average- to near-average snow-water equivalent. Regionally, on April 1, snow-water equivalent ranged from 50 to 89 percent. At most regional sites monitored during 1993-2004, snowpack ammonium, nitrate, and sulfate concentrations for 2004 were lower than the 12-year averages. Snowpack ammonium concentrations in the region were lower than average concentrations for the period at 61 percent of sites in the region, but showed a new pattern compared to previous years with three of the four highest 2004 concentrations observed in northern Colorado. Nitrate concentrations in 2004 were lower than the 12-year average for the year at 53 percent of regional sites, and typically occurred at sites in Wyoming, Idaho, and Montana where powerplants and large industrial areas were limited. A regional decrease in sulfate concentrations across most of the Rocky Mountains (with concentrations lower than the 12-year average at 84 percent of snowpack sites) was consistent with other monitoring of atmospheric deposition in the Western United States. Total mercury concentrations, although data are only available for the past 3 years, decreased slightly for the region as a whole in 2004 relative to 2003. Ratios of stable sulfur isotopes indicated a similar regional pattern as observed in recent years with sulfur-34 (d34S) values generally increasing northward from northern New Mexico and southern Colorado to northern Colorado, Wyoming, Idaho, and Montana.

Open-File Report↗

Chemistry of selected core samples, concentrate, tailings, and tailings pond waters: Pea Ridge iron (-lanthanide-gold) deposit, Washington County, Missouri

The Minerals at Risk and for Emerging Technologies Project of the U.S. Geological Survey (USGS) Mineral Resources Program is examining potential sources of lanthanide elements (rare earth elements) as part of its objective to provide up-to-date geologic information regarding mineral commodities likely to have increased demand in the near term. As part of the examination effort, a short visit was made to the Pea Ridge iron (-lanthanide-gold) deposit, Washington County, Missouri in October 2008. The deposit, currently owned by Wings Enterprises, Inc. of St. Louis, Missouri (Wings), contains concentrations of lanthanides that may be economic as a primary product or as a byproduct of iron ore production. This report tabulates the results of chemical analyses of the Pea Ridge samples and compares rare earth elements contents for world class lanthanide deposits with those of the Pea Ridge deposit. The data presented for the Pea Ridge deposit are preliminary and include some company data that have not been verified by the USGS or by the Missouri Department of Natural Resources, Division of Geology and Land Survey (DGLS), Geological Survey Program (MGS). The inclusion of company data is for comparative purposes only and does not imply an endorsement by either the USGS or MGS.

Missouri↗

Water and sediment chemistry of selected existing and potential habitats of the Mohave tui chub, Mojave National Preserve, California, 2018

The Mohave tui chub ( Siphateles bicolor mohavensis ) was nearly extirpated from the Mojave River drainage in California by the mid-twentieth century and was listed as endangered in 1970. A source population of Mohave tui chub exists at MC Spring in Zzyzx, California, and has been used for several re-establishment efforts in previous decades. Two potential habitats in the Mojave National Preserve with perennial sources of water were identified by the National Park Service as candidates for additional Mohave tui chub re-establishment: West Pond and Rainbow Wells Pond. West Pond, an artificial pond at Zzyzx near MC Spring, contained a population of Mohave tui chub that died off in 1985 because of changes in water quality. The pond was rehabilitated in the past several years through re-excavation and by pumping fresh groundwater into the pond. Rainbow Wells Pond is an abandoned excavated mine site in the Cima Dome area. The bottom of the excavation intersects the water table, forming a pond. In cooperation with the National Park Service, the U.S. Geological Survey monitored water-quality conditions at West Pond and Rainbow Wells Pond for 1 year to characterize the suitability of spring habitat for re-establishment of Mohave tui chub populations. Data were also collected at three existing Mohave tui chub habitats in Mojave National Preserve to provide further information on the range of acceptable physical and chemical conditions. Initial water-quality results at West Pond indicate the pond has similar water quality as existing Mohave tui chub habitats. Initial water-quality results at Rainbow Wells Pond indicate the dissolved oxygen concentrations and springtime water temperatures are less than the long-term tolerable ranges for Mohave tui chub.

California↗

Characterization of bottom-sediment, water, and elutriate chemistry at selected stations at Reelfoot Lake, Tennessee

To better-understand and predict the potential effect of dredging on water quality at Reelfoot Lake, chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water. Chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water collected at five stations in the lake during November 1988. Lake water was of the calcium magnesium bicarbonate type with an average dissolved-solids concentration of 120 milligrams per liter. Trace constituents were present in bottom sediments at concentrations representative of their average relative abundance in the earth?s crust. Elutriate waters prepared by mixing bottom sediment and lake water had suspended-solids concentrations as high as 2,000 milligrams per liter which exerted significant oxygen demand Trace constituents in the unfiltered elutriate waters were elevated with respect to lake water; elevated concentrations were attributable to the increased suspended-solids concentrations. Concentrations of total-recoverable copper, lead., and zinc in many elutriate waters exceeded U.S. Environmental Protection Agency?s water-quality criteria for the protection of freshwater aquatic life. The toxicity of elutriate waters, as measured by a 48-hour bioassay with Ceriodaphnia dubia, was low.

Tennessee↗