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Jeffrey R. Deacon

Publications and source records attributed to Jeffrey R. Deacon.

At least 19 recordsLinked to original sources

Prioritizing river basins for intensive monitoring and assessment by the US Geological Survey

The US Geological Survey (USGS) is currently (2020) integrating its water science programs to better address the nation’s greatest water resource challenges now and into the future. This integration will rely, in part, on data from 10 or more intensively monitored river basins from across the USA. A team of USGS scientists was convened to develop a systematic, quantitative approach to prioritize candidate basins for this monitoring investment to ensure that, as a group, the 10 basins will support the assessment and forecasting objectives of the major USGS water science programs. Candidate basins were the level-4 hydrologic units (HUC04) with some of the smaller HUC04s being combined; median candidate-basin area is 46,600 km 2 . Candidate basins for the contiguous United States (CONUS) were grouped into 18 hydrologic regions. Ten geospatial variables representing land use, climate change, water use, water-balance components, streamflow alteration, fire risk, and ecosystem sensitivity were selected to rank candidate basins within each of the 18 hydrologic regions. The two highest ranking candidate basins in each of the 18 regions were identified as finalists for selection as “Integrated Water Science Basins”; final selection will consider input from a variety of stakeholders. The regional framework, with only one basin selected per region, ensures that as a group, the basins represent the range in major drivers of the hydrologic cycle. Ranking within each region, primarily based on anthropogenic stressors of water resources, ensures that settings representing important water-resource challenges for the nation will be studied.

contiguous United States↗

What goes up must come down: Integrating air and water quality monitoring for nutrients

Excess nitrogen and phosphorus (“nutrients”) loadings continue to affect ecosystem function and human health across the U.S. Our ability to connect atmospheric inputs of nutrients to aquatic end points remains limited due to uncoupled air and water quality monitoring. Where connections exist, the information provides insights about source apportionment, trends, risk to sensitive ecosystems, and efficacy of pollution reduction efforts. We examine several issues driving the need for better integrated monitoring, including: coastal eutrophication, urban hotspots of deposition, a shift from oxidized to reduced nitrogen deposition, and the disappearance of pristine lakes. Successful coordination requires consistent data reporting; collocating deposition and water quality monitoring; improving phosphorus deposition measurements; and filling coverage gaps in urban corridors, agricultural areas, undeveloped watersheds, and coastal zones.

Environmental Science and Technology↗

Methods for computing water-quality loads at sites in the U.S. Geological Survey National Water Quality Network

The U.S. Geological Survey currently (2020) publishes information on concentrations and loads of water-quality constituents at 110 sites across the United States as part of the U.S. Geological Survey National Water Quality Network (NWQN). This report details historical and updated methods for computing water-quality loads at NWQN sites. The primary updates to historical load estimation methods include (1) an adaptation to methods for computing loads to the Gulf of Mexico; (2) the inclusion of loads and trends computed using the Weighted Regressions on Time, Discharge, and Season (WRTDS) and Weighted Regressions on Time, Discharge, and Season with Kalman filtering (WRTDS–K) methods; and (3) the inclusion of loads computed using continuous water-quality data. Loads computed using WRTDS and WRTDS–K and continuous water-quality data are provided along with those computed using historical methods. Various aspects of method updates are evaluated in this report to help users of water-quality loading data determine which estimation methods best suit their particular application.

Open-File Report↗

Aquatic assessment of the Pike Hill Copper Mine Superfund site, Corinth, Vermont

The Pike Hill Copper Mine Superfund site in Corinth, Orange County, Vermont, includes the Eureka, Union, and Smith mines along with areas of downstream aquatic ecosystem impairment. The site was placed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2004. The mines, which operated from about 1847 to 1919, contain underground workings, foundations from historical structures, several waste-rock piles, and some flotation tailings. The mine site is drained to the northeast by Pike Hill Brook, which includes several wetland areas, and to the southeast by an unnamed tributary that flows to the south and enters Cookville Brook. Both brooks eventually drain into the Waits River, which flows into the Connecticut River. The aquatic ecosystem at the site was assessed using a variety of approaches that investigated surface-water quality, sediment quality, and various ecological indicators of stream-ecosystem health. The degradation of surface-water quality is caused by elevated concentrations of copper, and to a lesser extent cadmium, with localized effects caused by aluminum, iron, and zinc. Copper concentrations in surface waters reached or exceeded the USEPA national recommended chronic water-quality criteria for the protection of aquatic life in all of the Pike Hill Brook sampling locations except for the location farthest downstream, in half of the locations sampled in the tributary to Cookville Brook, and in about half of the locations in one wetland area located in Pike Hill Brook. Most of these same locations also contained concentrations of cadmium that exceeded the chronic water-quality criteria. In contrast, surface waters at background sampling locations were below these criteria for copper and cadmium. Comparison of hardness-based and Biotic Ligand Model (BLM)-based criteria for copper yields similar results with respect to the extent or number of stations impaired for surface waters in the affected area. However, the BLM-based criteria are commonly lower values than the hardness-based criteria and thus suggest a greater degree or magnitude of impairment at the sampling locations. The riffle-habitat benthic invertebrate richness and abundance data correlate strongly with the extent of impact based on water quality for both brooks. Similarly, the fish community assessments document degraded conditions throughout most of Pike Hill Brook, whereas the data for the tributary to Cookville Brook suggest less degradation to this brook. The sediment environment shows similar extents of impairment to the surface-water environment, with most sampling locations in Pike Hill Brook, including the wetland areas, and the tributary to Cookville Brook affected. Sediment impairment is caused by elevated copper concentrations, although localized degradation due to elevated cadmium and zinc concentrations was documented on the basis of exceedances of probable effects concentrations (PECs). In contrast to impairment determined by exceedances of PECs, equilibrium-partitioning sediment benchmarks (based on simultaneously extracted metals, acid volatile sulfides, and total organic carbon) predict no toxic effects in sediments at the background locations and uncertain toxic effects throughout Pike Hill Brook and the tributary to Cookville Brook, with the exception of the most downstream Cookville Brook location, which indicated no toxic effects. Acute laboratory toxicity testing using the amphipod Hyalella azteca and the midge Chironomus dilutus on pore waters extracted from sediment in situ indicate impairment (based on tests with H. azteca ) at only one location in Pike Hill Brook and no impairment in the tributary to Cookville Brook. Chronic laboratory sediment toxicity testing using H. azteca and C. dilutus indicated toxicity in Pike Hill Brook at several locations in the lower reach and two locations in the tributary to Cookville Brook. Toxicity was not indicated for either species in sediment from the most acidic metal-rich location, likely due to the low lability of copper in that sediment, as indicated by a low proportion of extractable copper (simultaneously extracted metal (SEM) copper only 5 percent of total copper) and due to the flushing of acidic metal-rich pore water from experimental chambers as overlying test water was introduced before and replaced periodically during the toxicity tests. Depositional habitat invertebrate richness and abundance data generally agreed with the results of toxicity tests and with the extent of impact in the watersheds on the basis of sediment and pore waters. The information was used to develop an overall assessment of the impact of mine drainage on the aquatic system downstream from the Pike Hill copper mines. Most of Pike Hill Brook, including several wetland areas that are all downstream from the Eureka and Union mines, was found to be impaired on the basis of water-quality data and biological assessments of fish or benthic invertebrate communities. In contrast, only one location in the tributary to Cookville Brook, downstream from the Smith mine, is definitively impaired. The biological community begins to recover at the most downstream locations in both brooks due to natural attenuation from mixing with unimpaired streams. On the basis of water quality and biological assessment, the reference locations were of good quality. The sediment toxicity, chemistry, and aquatic community survey data suggest that the sediments could be a source of toxicity in Pike Hill Brook and the tributary to Cookville Brook. On the basis of water quality, sediment quality, and biologic communities, the impacts of mine drainage on the aquatic ecosystem health of the watersheds in the study area are generally consistent with the toxicity suggested from laboratory toxicity testing on pore water and sediments.

Vermont↗

Aquatic assessment of the Ely Copper Mine Superfund site, Vershire, Vermont

The Ely Mine, which operated from 1821 to 1905, and its area of downstream impact constitute the Ely Copper Mine Superfund site. The site was placed on the National Priorities List in 2001. The mine comprises underground workings, foundations from historical structures, several waste-rock piles, roast beds associated with the smelting operation, and slag piles resulting from the smelting. The mine site is drained by Ely Brook, which includes several tributaries, one of which drains a series of six ponds. Ely Brook empties into Schoolhouse Brook, which flows 3.3 kilometers and joins the Ompompanoosuc River. The aquatic ecosystem at the site was assessed using a variety of approaches that investigated surface-water quality, sediment quality, and various ecological indicators of stream-ecosystem health. The degradation of surface-water quality is dominated by copper with localized effects caused by iron, aluminum, cadmium, and zinc. Chronic water-quality criteria for copper are exceeded in the surface water of four of the six ponds on the Ely Brook tributary, and all of Ely Brook and Schoolhouse Brook, and of the Ompompanoosuc River downstream of the confluence with Schoolhouse Brook. Comparison of hardness-based and Biotic Ligand Model-based water-quality criteria for copper yields similar results with respect to extent of impairment. However, the Biotic Ligand Model criteria are mostly lower than the hardness-based criteria and thus suggest a greater degree of impairment, particularly in the Ely Brook watershed, where dissolved organic carbon concentrations and pH values are lower. Surface-water toxicity testing correlates strongly with the extent of impact. Likewise, riffle-habitat benthic invertebrate richness and abundance data support these results through the stream environment. Similarly, the index of biotic integrity for the fish community in Schoolhouse Brook and the Ompompanoosuc River document degraded habitats throughout Schoolhouse Brook from Ely Brook down to the Ompompanoosuc River. The sediment environment shows similar extents of impairment also dominated by copper, although localized degradation due to chromium, nickel, lead, and zinc was documented on the basis of probable effects concentrations. In contrast, equilibrium-partitioning sediment benchmarks indicate no toxic effects would be expected in sediments at the reference sites, and uncertain toxic effects throughout Ely Brook and Schoolhouse Brook, except for the reference sites and site EB-600M. The results for site EB-600M indicate predicted toxic effects. Acute toxicity testing of in situ pore waters using Hyalella azteca indicates severe impacts in Ely Brook reaching 100 percent lethality at site EB-90M. Acute toxicity testing of in situ pore waters using Chironomus dilutus shows similar, but not as severe, toxicity. Neither set of in situ pore-water toxicity tests showed significant impairment in Schoolhouse Brook or the Ompompanoosuc River. Chronic sediment toxicity testing using Hyalella azteca indicated significant toxicity in Ely Brook, except at site EB-90M, and in Schoolhouse Brook. The low toxicity of EB-90M may be a reflection of the low lability of copper in that sediment as indicated by a low proportion of extractable copper (1.1 percent). Depositional-targeted habitat invertebrate richness and abundance data support these conclusions for the entire watershed, as do the index of biotic integrity data from the fish community. The information was used to develop an overall assessment of the impact on the aquatic system that appears to be a result of the acid rock drainage at the Ely Mine. More than 700 meters of Ely Brook, including two of the six ponds, were found to be severely impacted, on the basis of water-quality data and biological assessments. The reference location was of good quality based on the water quality and biological assessment. More than 3,125 meters of Schoolhouse Brook are also severely impacted, on the basis of water-quality data and biological assessments. The biological community begins to recover near the confluence with the Ompompanoosuc River. The evidence is less conclusive regarding the Ompompanoosuc River. The sediment data suggest that the sediments could be a source of toxicity in Ely Brook and Schoolhouse Brook. The surface-water assessment is consistent with the outcome of a surface-water toxicity testing program performed by the U.S. Environmental Protection Agency for Ely Brook and Schoolhouse Brook and a surface-water toxicity testing program and in situ amphibian testing program for the ponds.

Vermont↗

Surface-Water Hydrology and Quality at the Pike Hill Superfund Site, Corinth, Vermont, October 2004 to December 2005

The hydrology and quality of surface water in and around the Pike Hill Brook watershed, in Corinth, Vermont, was studied from October 2004 to December 2005 by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency (USEPA). Pike Hill was mined intermittently for copper from 1847 to 1919 and the site is known to be contributing trace elements and acidity to Pike Hill Brook and an unnamed tributary to Cookville Brook. The site has been listed as a Superfund site since 2004. Streamflow, specific conductance, pH, and water temperature were measured continuously and monthly at three sites on Pike Hill Brook to determine the variation in these parameters over an annual cycle. Synoptic water-quality sampling was done at 10 stream sites in October 2004, April 2005, and June 2005 and at 13 stream sites in August 2005 to characterize the quality of surface water in the watershed on a seasonal and spatial basis, as well as to assess the effects of wetlands on water quality. Samples for analysis of benthic macroinvertebrate populations were collected at 11 stream sites in August 2005. Water samples were analyzed for 5 major ions and 32 trace elements. Concentrations of trace elements at sites in the Pike Hill Brook watershed exceeded USEPA National Recommended Water Quality Criteria acute and chronic toxicity standards for aluminum, iron, cadmium, copper, and zinc. Concentrations of copper exceeded the chronic criteria in an unnamed tributary to Cookville Brook in one sample. Concentrations of sulfate, calcium, aluminum, iron, cadmium, copper, and zinc decreased with distance from a site directly downstream from the mine (site 1), as a result of dilution and through sorption and precipitation of the trace elements. Maximum concentrations of aluminum, iron, cadmium, copper, and zinc were observed during spring snowmelt. Concentrations of sulfate, calcium, cadmium, copper, and zinc, and instantaneous loads of calcium and aluminum were statistically different (p<0.05) among the three continuously monitored sites (sites 1, 4, and 5). Instantaneous loads of aluminum, iron, and copper decreased by one to three orders of magnitude from site 1 to a site 1.1 mi downstream (site 4). Instantaneous loads of sulfate were similar between sites 1, 4, and at a site 3 mi downstream (site 5). Instantaneous loads of cadmium and zinc were similar between sites 1 and 4, and loads of iron and copper were similar between sites 4 and 5. Loads of chemical constituents were compared at site 1 (closest to the mine waste piles) and site 5 (near the mouth of Pike Hill Brook and below a majority of the wetlands). Annually, the loads of dissolved cadmium and zinc at site 1 were about five times greater than loads at site 5, and the load of dissolved copper at site 1 was about 17 times greater than at site 5. The ratio of loads for dissolved cadmium, copper, and zinc to total cadmium, copper, and zinc at site 1 was about 1. Samples collected in Pike Hill Brook upstream and downstream from the wetlands during low flows in August 2005 showed that oxidation of ferrous iron and precipitation of iron-hydroxides were probably not affecting trace metals in the wetlands through sorption; however, a significant portion of the iron entering the wetlands was in particulate form and may have transported sorbed copper and other trace metals. Thus, aerobic activity in the wetlands was probably not affecting metal cycling in the watershed. Concentrations and loads of sulfate may be unlikely to define unequivocally the role of the wetlands with regard to anaerobic bacterial sulfate reduction; however, bacterial sulfate removal may have affected loads of sulfate. Loads of copper increased downstream from the wetlands and may reflect the reductive dissolution of ferric hydroxide particulates in anaerobic parts of the wetlands.Concentrations of dissolved iron increased downstream from the wetlands. The most apparent effects on the macroinvertebr

Scientific Investigations Report↗

Relation of Lake-Floor Characteristics to the Distribution of Variable Leaf Water-Milfoil in Moultonborough Bay, Lake Winnipesaukee, New Hampshire, 2005

Geophysical, water, and sediment surveys were done to characterize the effects of surficial geology, water and sediment chemistry, and surficial-sediment composition on the distribution of variable leaf water-milfoil in Moultonborough Bay, Lake Winnipesaukee, New Hampshire. Geophysical surveys were conducted in a 180-square-kilometer area, and water-quality and sediment samples were collected from 24 sites in the survey area during July 2005. Swath-bathymetric data revealed that Moultonborough Bay ranged in depth from less than 1 meter (m) to about 15 m and contained three embayments. Seismic-reflection profiles revealed erosion of the underlying bedrock and subsequent deposition of glaciolacustrine and Holocene lacustrine sediments within the survey area. Sediment thickness ranged from 5 m along the shoreward margins to more than 15 m in the embayments. Data from sidescan sonar, surficial-sediment samples, bottom photographs, and video revealed three distinct lake-floor environments: rocky nearshore, mixed nearshore, and muddy basin. Rocky nearshore environments were found in shallow water (less than 5 m deep) and contained sediments ranging from coarse silt to very coarse sand. Mixed nearshore environments also were found in shallow water and contained sediments ranging from silt to coarse sand with different densities of aquatic vegetation. Muddy basin environments contained the finest-grained sediments, ranging from fine to medium silt, and were in the deepest waters of the bay. Acoustic Ground Discrimination Systems (AGDS) survey data revealed that 86 percent of the littoral zone (the area along the margins of the bay and islands that extends from 0 to 4.3 m in water depth) contained submerged aquatic vegetation (SAV) in varying densities: approximately 36 percent contained SAV bottom cover of 25 percent or less, 43 percent contained SAV bottom cover of more than 25 and less than 75 percent, and approximately 7 percent contained SAV bottom cover of more than 75 percent. SAV included variable leaf water-milfoil, native milfoil, bassweed, pipewort, and other species, which were predominantly found near shoreward margins and at depths ranging from less than 1 to 4 m. AGDS data were used in a Geographic Information System to generate an interpolated map that distinguished variable leaf water-milfoil from other SAV. Furthermore, these data were used to isolate areas susceptible to variable leaf water-milfoil growth. Approximately 21 percent of the littoral zone contained dense beds (more than 59 percent bottom cover) of variable leaf water-milfoil, and an additional 44 percent was determined to be susceptible to variable leaf water-milfoil infestation. Depths differed significantly between sites with variable leaf water-milfoil and sites with other SAV (p = 0.04). Variable leaf water-milfoil was found at depths that ranged from 1 to 4 m, and other SAV had a depth range of 1 to 2 m. Although variable leaf water-milfoil was observed at greater depths than other SAV, it was not observed below the photic zone. Analysis of constituent concentrations from the water column, interstitial pore water, and sediment showed little correlation with the presence of variable leaf water-milfoil, with two exceptions. Iron concentrations were significantly lower at variable leaf water-milfoil sites than at other sampling sites (p = 0.04). Similarly, the percentage of total organic carbon also was significantly lower at the variable leaf water-milfoil sites than at other sampling sites (p = 0.04). Surficial-sediment-grain size had the greatest correlation to the presence of variable leaf water-milfoil. Variable leaf water-milfoil was predominantly growing in areas of coarse sand (median grain-size 0.62 millimeters). Surficial-sediment-grain size was also correlated with total ammonia plus organic nitrogen (Rho = 0.47; p = 0.02) and with total phosphorus (Rho = 0.44; p = 0.05) concentrations in interstitial pore-water samples.

Scientific Investigations Report↗

Assessment of total nitrogen in the upper Connecticut River basin in New Hampshire, Vermont, and Massachusetts, December 2002–September 2005

A study of total nitrogen concentrations and loads was conducted from December 2002 to September 2005 at 13 river sites in the upper Connecticut River Basin. Ten sites were selected to represent contributions of nitrogen from forested, agricultural, and urban land. Three sites were distributed spatially on the main stem of the Connecticut River to assess the cumulative total nitrogen loads. To further improve the understanding of the sources and concentrations and loads of total nitrogen in the upper Connecticut River Basin, ambient surface water-quality sampling was supplemented with sampling of effluent from 19 municipal and paper mill wastewater-treatment facilities. Mean concentrations of total nitrogen ranged from 0.19 to 2.8 milligrams per liter (mg/L) at river sampling sites. Instantaneous mean loads of total nitrogen ranged from 162 to 58,300 pounds per day (lb/d). Estimated mean annual loads of total nitrogen ranged from 49,100 to 21.6 million pounds per year (lb/yr) with about 30 to 55 percent of the loads being transported during the spring. The estimated mean annual yields of total nitrogen ranged from 1,190 to 7,300 pounds per square mile per year (lb/mi 2 )/yr. Mean concentrations of total nitrogen ranged from 4.4 to 30 mg/L at wastewater-treatment sampling sites. Instantaneous mean loads of total nitrogen from municipal wastewater-treatment facilities ranged from 36 to 1,780 lb/d. Instantaneous mean loads of total nitrogen from paper mill wastewater-treatment facilities ranged from 96 to 160 lb/d. The median concentration of total nitrogen was 0.24 mg/L at forested sites, 0.48 mg/L at agricultural sites, 0.54 mg/L at urban sites, 0.48 mg/L at main-stem sites, and 14 mg/L at wastewater-treatment sites. Concentrations of total nitrogen at forested sites were significantly less than at all other site types (p<0.05). Concentrations of total nitrogen at agricultural, urban, and main stem sites were not significantly different among each other (p>0.05) but were significantly greater (p<0.05) than at forested sites and significantly less than concentrations at wastewater-treatment sites (p<0.05). Total nitrogen concentrations at wastewater-treatment sites were significantly different from all other site types (p<0.05). Annual yields of total nitrogen ranged from 732 to 1,920 (lb/mi 2 )/yr at forested sites; 1,550 to 2,980 (lb/mi 2 )/yr at agricultural sites; 1,280 to 1,860 (lb/mi 2 )/yr at urban sites that were not directly affected by wastewater effluent; 7,090 to 7,770 (lb/mi 2 )/yr at an urban site directly affected by wastewater effluent; and 1,300 to 2,390 (lb/mi 2 )/yr at main-stem sites. In this study, the mean annual load and yield of total nitrogen at the Connecticut River at Wells River, VT, was estimated at 4.47 million lb/yr and 1,690 (lb/mi 2 )/yr, respectively. The mean annual load and yield of total nitrogen at the Connecticut River at North Walpole, NH, was estimated at 9.60 million lb/yr and 1,750 (lb/mi 2 )/yr, respectively. The mean annual load and yield of total nitrogen leaving the upper Connecticut River Basin, as estimated at the Connecticut River at Thompsonville, CT, was 21.6 million lb/yr and 2,230 (lb/mi 2 )/yr, respectively.

Massachusetts, New Hampshire, Vermont↗

Geochemical Characterization of Mine Waste, Mine Drainage, and Stream Sediments at the Pike Hill Copper Mine Superfund Site, Orange County, Vermont

The Pike Hill Copper Mine Superfund Site in the Vermont copper belt consists of the abandoned Smith, Eureka, and Union mines, all of which exploited Besshi-type massive sulfide deposits. The site was listed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2004 due to aquatic ecosystem impacts. This study was intended to be a precursor to a formal remedial investigation by the USEPA, and it focused on the characterization of mine waste, mine drainage, and stream sediments. A related study investigated the effects of the mine drainage on downstream surface waters. The potential for mine waste and drainage to have an adverse impact on aquatic ecosystems, on drinking- water supplies, and to human health was assessed on the basis of mineralogy, chemical concentrations, acid generation, and potential for metals to be leached from mine waste and soils. The results were compared to those from analyses of other Vermont copper belt Superfund sites, the Elizabeth Mine and Ely Copper Mine, to evaluate if the waste material at the Pike Hill Copper Mine was sufficiently similar to that of the other mine sites that USEPA can streamline the evaluation of remediation technologies. Mine-waste samples consisted of oxidized and unoxidized sulfidic ore and waste rock, and flotation-mill tailings. These samples contained as much as 16 weight percent sulfides that included chalcopyrite, pyrite, pyrrhotite, and sphalerite. During oxidation, sulfides weather and may release potentially toxic trace elements and may produce acid. In addition, soluble efflorescent sulfate salts were identified at the mines; during rain events, the dissolution of these salts contributes acid and metals to receiving waters. Mine waste contained concentrations of cadmium, copper, and iron that exceeded USEPA Preliminary Remediation Goals. The concentrations of selenium in mine waste were higher than the average composition of eastern United States soils. Most mine waste was potentially acid generating because of paste-pH values of less than 4 and negative net-neutralization potentials (NNP). The processed flotation-mill tailings, however, had a near neutral paste pH, positive NNP, and a few weight percent calcite. Leachate tests indicated that elements and compounds such as Al, Cd, Cu, Fe, Mn, Se, SO4, and Zn were leached from mine waste in concentrations that exceeded aquatic ecosystem and drinking-water standards. Mine waste from the Pike Hill mines was chemically and mineralogically similar to that from the Elizabeth and Ely mines. In addition, metals were leached and acid was produced from mine waste from the Pike Hill mines in comparable concentrations to those from the Elizabeth and Ely mines, although the host rock of the Pike Hill deposits contains significant amounts of carbonate minerals and, thus, a greater acid-neutralizing capacity when compared to the host rocks of the Elizabeth and Ely deposits. Water samples collected from unimpacted parts of the Waits River watershed generally contained lower amounts of metals compared to water samples from mine drainage, were alkaline, and had a neutral pH, which was likely because of calcareous bedrock. Seeps and mine pools at the mine site had acidic to neutral pH, ranged from oxic to anoxic, and generally contained concentrations of metals, for example, aluminum, cadmium, copper, iron, and zinc, that exceeded aquatic toxicity standards or drinking-water standards, or both. Surface waters directly downstream of the Eureka and Union mines were acidic, as indicated by pH values from 3.1 to 4.2, and contained high concentrations of some elements including as much as 11,400 micrograms per liter (?g/L) Al, as much as 22.9 ?g/L Cd, as much as 6,790 ?g/L Cu, as much as 23,300 ?g/L Fe, as much as 1,400 ?g/L Mn, and as much as 3,570 ?g/L Zn. The concentrations of these elements exceeded water-quality guidelines. Generally, in surface waters, the pH increased and the concentrations of these elemen

Scientific Investigations Report↗

Effects of urbanization on stream quality at selected sites in the seacoast region in New Hampshire, 2001-03

A study of selected water-quality and macroinvertebrate community data was conducted at 10 stream sites in the Seacoast region of New Hampshire to determine if a relation is present between stream quality and the extent of urbanization in a watershed. Watersheds with similar characteristics, but varying in their degree of urban development, were studied. The percent of impervious surface, the percent of urban land use in a watershed, and the percent of urban land use in two types of stream buffers were compared and correlated with stream-quality variables. Specific conductance, turbidity, nitrite plus nitrate yields, and selected macroinvertebrate community data were significantly correlated with most measures of urbanization used in this study; however, concentrations and total phosphorus yields were not statistically correlated with most measures of urbanization in this study. The measures of urbanization that had the highest correlations with stream-quality variables were those measures that were associated with the percent of urban land in buffer zones near and upstream of a sampling site. A water-quality and habitat conditions score was negatively correlated with the percent of urban land in a 1-kilometer radial buffer of the sampling site (rho (r) = -0.86; p < 0.001), the percent of impervious surface (r = -0.70; p < 0.05), and the percent of urban land in the watershed (r = -0.67; p < 0.05). A biological condition score also was negatively correlated with the percent of urban land in a 1-kilometer radial buffer of the sampling site (r = -0.95; p < 0.0001), the percent of impervious surface (r = -0.75; p < 0.05), and the percent of urban land in the watershed (r = -0.79; p < 0.01). The percent of urban land in a 25-meter stream buffer along the stream corridor also had negative correlations with a water-quality and habitat conditions score (r = -0.80; p < 0.01) and a biological condition score (r = -0.86; p < 0.01). Mean Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa richness showed a response to urbanization in a watershed, indicating that EPT taxa richness may be an appropriate metric to evaluate the effects of urban land use on small streams in this region. Results from this study indicate that the percent of urban land use in buffer zones and the percent of impervious surface in a watershed can be used as indicators of stream quality.

Scientific Investigations Report↗

Estimation of Total Nitrogen and Phosphorus in New England Streams Using Spatially Referenced Regression Models

The U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency (USEPA) and the New England Interstate Water Pollution Control Commission (NEIWPCC), has developed a water-quality model, called SPARROW (Spatially Referenced Regressions on Watershed Attributes), to assist in regional total maximum daily load (TMDL) and nutrient-criteria activities in New England. SPARROW is a spatially detailed, statistical model that uses regression equations to relate total nitrogen and phosphorus (nutrient) stream loads to nutrient sources and watershed characteristics. The statistical relations in these equations are then used to predict nutrient loads in unmonitored streams. The New England SPARROW models are built using a hydrologic network of 42,000 stream reaches and associated watersheds. Watershed boundaries are defined for each stream reach in the network through the use of a digital elevation model and existing digitized watershed divides. Nutrient source data is from permitted wastewater discharge data from USEPA's Permit Compliance System (PCS), various land-use sources, and atmospheric deposition. Physical watershed characteristics include drainage area, land use, streamflow, time-of-travel, stream density, percent wetlands, slope of the land surface, and soil permeability. The New England SPARROW models for total nitrogen and total phosphorus have R-squared values of 0.95 and 0.94, with mean square errors of 0.16 and 0.23, respectively. Variables that were statistically significant in the total nitrogen model include permitted municipal-wastewater discharges, atmospheric deposition, agricultural area, and developed land area. Total nitrogen stream-loss rates were significant only in streams with average annual flows less than or equal to 2.83 cubic meters per second. In streams larger than this, there is nondetectable in-stream loss of annual total nitrogen in New England. Variables that were statistically significant in the total phosphorus model include discharges for municipal wastewater-treatment facilities and pulp and paper facilities, developed land area, agricultural area, and forested area. For total phosphorus, loss rates were significant for reservoirs with surface areas of 10 square kilometers or less, and in streams with flows less than or equal to 2.83 cubic meters per second. Applications of SPARROW for evaluating nutrient loading in New England waters include estimates of the spatial distributions of total nitrogen and phosphorus yields, sources of the nutrients, and the potential for delivery of those yields to receiving waters. This information can be used to (1) predict ranges in nutrient levels in surface waters, (2) identify the environmental variables that are statistically significant predictors of nutrient levels in streams, (3) evaluate monitoring efforts for better determination of nutrient loads, and (4) evaluate management options for reducing nutrient loads to achieve water-quality goals.

Scientific Investigations Report↗

Relations of benthic macroinvertebrates to concentrations of trace elements in water, streambed sediments, and transplanted bryophytes and stream habitat conditions in nonmining and mining areas of the upper Colorado River basin, Colorado, 1995-98

Intensive mining activity and highly mineralized rock formations have had significant impacts on surface-water and streambed-sediment quality and aquatic life within the upper reaches of the Uncompahgre River in western Colorado. A synoptic study by the U.S. Geological Survey National Water-Quality Assessment Program was completed in the upper Uncompahgre River Basin in 1998 to better understand the relations of trace elements (with emphasis on aluminum, arsenic, copper, iron, lead, and zinc concentrations) in water, streambed sediment, and aquatic life. Water-chemistry, streambed-sediment, and benthic macroinvertebrate samples were collected during low-flow conditions between October 1995 and July 1998 at five sites on the upper Uncompahgre River, all downstream from historical mining, and at three sites in drainage basins of the Upper Colorado River where mining has not occurred. Aquatic bryophytes were transplanted to all sites for 15 days of exposure to the water column during which time field parameters were measured and chemical water-quality and benthic macroinvertebrate samples were collected. Stream habitat characteristics also were documented at each site. Certain attributes of surface-water chemistry among streams were significantly different. Concentrations of total aluminum, copper, iron, lead, and zinc in the water column and concentrations of dissolved aluminum, copper, and zinc were significantly different between nonmining and mining sites. Some sites associated with mining exceeded Colorado acute aquatic-life standards for aluminum, copper, and zinc and exceeded Colorado chronic aquatic-life standards for aluminum, copper, iron, lead, and zinc. Concentrations of copper, lead, and zinc in streambed sediments were significantly different between nonmining and mining sites. Generally, concentrations of arsenic, copper, lead, and zinc in streambed sediments at mining sites exceeded the Canadian Sediment Quality Guidelines probable effect level (PEL), except at two mining sites where concentrations of copper and zinc were below the PEL. Concentrations of arsenic, copper, iron, and lead in transplanted bryophytes were significantly different between nonmining and mining sites. Bioconcentration factors calculated for 15-day exposure using one-half of the minimum reporting level were significantly different between nonmining and mining sites. In general, concentrations of trace elements in streambed sediment and transplanted bryophytes were more closely correlated than were the concentrations of trace elements in the water column with streambed sediments or concentrations in the water column with transplanted bryophytes. Stream habitat was rated as optimal to suboptimal using the U.S. Environmental Protection Agency Rapid Bioassessment Protocols for all sites in the study area. Generally, stream habitat conditions were similar at nonmining compared to mining sites and were suitable for diverse macroinvertebrate communities. All study sites had optimal instream habitat except two mining sites with suboptimal instream habitat because of disturbances in stream habitat. The benthic macroinvertebrate community composition at nonmining sites and mining sites differed. Mining sites had significantly lower total abundance of macroinvertebrates, fewer numbers of taxa, and lower dominance of Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies), and a larger percentage of tolerant species than did nonmining sites. The predominance of Baetis sp. (mayflies), Hydropsychidae (caddisflies), and large percentage of Orthocladiinae chironomids (midges) at mining sites indicated that these species may be tolerant to elevated trace-element concentrations. The absence of Heptageniidae (mayflies), Chloroperlidae (stoneflies), and Rhyacophila sp. (caddisflies) at mining sites indicated that these species may be sensitive to elevated trace-element concentrations. Comparison of field parameters and chemical water-quality characteristics to biological conditions was conducted using a water quality score (WQS) and a biological condition score (BCS). In general, as the WQS increased, the BCS also increased. Nonmining sites had higher WQS's and BCS's than mining sites. The BCS categorized the nonmining sites as nonimpaired, and the mining sites were categorized as slightly to severely impaired. Other important factors in this study that influenced surface-water quality include stream pH, chemical solubility of trace elements, stream temperature, stream elevation, organic inputs into the stream, basin geology, and stream habitat at a site. Although high concentrations of some trace elements may occur naturally, trace-element concentrations at mining sites were much higher. High trace-element concentrations appear to affect the macroinvertebrate communities more than the other factors at these sites. Mayfly, stonefly, and caddisfly abundance and the percentage of midge species are good indicators of mining effects at sites in the study area.

Colorado↗

Algal Data from Selected Sites in the Upper Colorado River Basin, Colorado, Water Years 1996-97

Algal community samples were collected at 15 sites in the Upper Colorado River Basin in Colorado as part of the National Water-Quality Assessment Program during water years 1996-97. Sites sampled were located in two physiographic provinces, the Southern Rocky Mountains and the Colorado Plateaus, and represented agricultural, mining, urban, and mixed land uses and background conditions. Algal samples were collected once per year during low-flow conditions. Quantitative algal samples were collected within two targeted instream habitat types including a taxonomically richest-targeted habitat and a depositional-targeted habitat. This report presents the algal community data collected at the fixed sites in the Upper Colorado River Basin study unit. Algal data include densities (abundance of cells per square centimeter of substrate) and biovolumes (cubic micrometers of cells per square centimeter of substrate) for the two habitat types. Quality-assurance and quality-control results for algal samples indicate that the largest sampling variability tends to occur in samples from small streams.

Open-File Report↗

Water quality in the upper Colorado River basin, Colorado, 1996-98

This report summarizes major findings about water quality in the upper Colorado River basin that emerged from an assessment conducted between 1996 and 1998 by the U.S. Geological Survey (USGS) National Water Quality Assessment (NAWQA) Program. Water quality is discussed in terms of local and regional issues and compared to conditions found in all 36 NAWQA study areas assessed to date. Findings are also explained in the context of selected national benchmarks, such as those for drinking water quality and the protection of aquatic organisms.

Colorado↗

Characterization of selected biological, chemical, and physical conditions at fixed sites in the Upper Colorado River Basin, Colorado, 1995-98

Biological community samples were collected at 15 sites in the Upper Colorado River Basin (UCOL) in Colorado as part of the National Water-Quality Assessment (NAWQA) Program. Sites sampled in two physiographic provinces, the Southern Rocky Mountains and the Colorado Plateau, represented agriculture, mining, urban and recreation, and mixed land uses and background conditions. Nine measures of water quality, which include information on nutrients, specific conductance (a surrogate for salinity), trace elements in streambed sediment, pesticides in fish tissue, fish communities, and macroinvertebrate richness and composition and stream habitat were used for comparisons among sites within the two physiographic provinces. Sampling sites from three other NAWQA study units—the Rio Grande Valley, the South Platte River Basin, and the Upper Snake River Basin study units—were categorized on the basis of land use and stream size in order to develop a larger data set for comparison to sites in the UCOL. Three categories of land use—forested (includes mining, urban and recreation, and background), agriculture, and mixed—were used for comparison to the UCOL fixed sites. Results indicated that all sites other than the Colorado River below Baker Gulch (a background site) showed some water-quality characteristics to be significantly affected. Results indicated that the concentrations of cadmium and zinc in streambed sediment at mining land-use sites in the Southern Rocky Mountains physiographic province generally were orders of magnitude higher than streambed-sediment concentrations at the background site. Streambed-sediment concentrations at mining land-use sites in the UCOL were greater than the 75 th percentile of concentrations from sites in the three other NAWQA study units. Fish communities and habitat conditions were degraded at mining land-use sites compared to the background site. Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness and the percentage of EPT were lower at mining land-use sites than at the background site and were less than the 50 th percentile of those for sites from the three other NAWQA study units. Nutrient concentrations at urban and recreation sites in the Southern Rocky Mountain physiographic province generally were greater than concentrations at the background site and generally were between the 25 th and 90 th percentile of concentrations for sites from the three other NAWQA study units. Habitat conditions and fish communities at urban and recreation sites were slightly degraded compared to the background site. EPT richness and the percentage of EPT were lower at urban and recreation sites than at the background site and were between the 25 th and 75 th percentile of those for sites from the three other NAWQA study units. The percentage of Chironomidae, which may be indicative of pollutant-tolerant organisms, was higher at urban and recreation sites than at the background site. Mixed land-use sites in the Southern Rocky Mountains physiographic province had similar nutrient concentrations and similar cadmium and zinc streambed-sediment concentrations. Fish-community degradation index values were very different among the three mixed land-use sites in the Southern Rocky Mountains physiographic province. Larger percentages of omnivores and anomalies such as lesions and deformities at two mixed land-use sites resulted in higher degradation values of the fish community. Agriculture land-use sites had higher concentrations of nutrients and selenium than the background site in the Colorado Plateau physiographic province. Concentrations of p,p '-DDE in fish tissue at agriculture sites were higher than the 75 th percentile of concentrations for sites from the three other NAWQA study units. Fish communities had degradation values near the 75 th percentile for agriculture sites. The percentage of EPT was low at agriculture sites when compared to the background site. Two mixed land-use sites in the Colorado Plateau physiographic province had similar concentrations of nutrients, selenium, and p,p '-DDE, and similar EPT richness and composition. These two sites were located downstream from agricultural and urban activities. Some water-quality measures at these two sites indicated degradation compared to a mixed land-use site upstream from most of the agriculture and urban activities in the Colorado Plateau physiographic province.

Colorado↗