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B. C. Osmundson

Publications and source records attributed to B. C. Osmundson.

7 recordsLinked to original sources
USGS2000

Selenium concentrations in the Colorado pikeminnow (Ptychocheilus lucius): Relationship with flows in the upper Colorado River

A Department of the Interior (DOI) irrigation drainwater study of the Uncompahgre Project area and the Grand Valley in western Colorado revealed high selenium concentrations in water, sediment, and biota samples. The lower Gunnison River and the Colorado River in the study area are designated critical habitat for the endangered Colorado pikeminnow (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus). Because of the endangered status of these fish, sacrificing individuals for tissue residue analysis has been avoided; consequently, little information existed regarding selenium tissue residues. In 1994, muscle plugs were collected from a total of 39 Colorado pikeminnow captured at various Colorado River sites in the Grand Valley for selenium residue analysis. The muscle plugs collected from 16 Colorado pikeminnow captured at Walter Walker State Wildlife Area (WWSWA) contained a mean selenium concentration of 17 ??g/g dry weight, which was over twice the recommended toxic threshold guideline concentration of 8 ??g/g dry weight in muscle tissue for freshwater fish. Because of elevated selenium concentrations in muscle plugs in 1994, a total of 52 muscle plugs were taken during 1995 from Colorado pikeminnow staging at WWSWA. Eleven of these plugs were from fish previously sampled in 1994. Selenium concentrations in 9 of the 11 recaptured fish were significantly lower in 1995 than in 1994. Reduced selenium in fish may in part be attributed to higher instream flows in 1995 and lower water selenium concentrations in the Colorado River in the Grand Valley. In 1996, muscle plugs were taken from 35 Colorado squawfish captured at WWSWA, and no difference in mean selenium concentrations were detected from those sampled in 1995. Colorado River flows during 1996 were intermediate to those measured in 1994 and 1995.

Archives of Environmental Contamination and Toxico↗
USGS1997

Field screening of water, soil, bottom sediment, and biota associated with irrigation drainage in the Dolores Project and the Mancos River Basin, southwestern Colorado, 1994

A reconnaissance investigation for the National Irrigation Water Quality Program in 1990 indicated elevated selenium concentrations in some water and biota samples collected in the Dolores Project in southwestern Colorado. High selenium concentrations also were indicated in bird samples collected in the Mancos Project in 1989. In 1994, field screenings were done in parts of the Dolores Project and Mancos River Basin to collect additional selenium data associated with irrigation inthose areas. Selenium is mobilized from soils in newly irrigated areas of the Dolores Project called the Dove Creek area, which includes newly (since 1987) irrigated land north of Cortez and south of Dove Creek.Selenium was detected in 18 of 20stream samples, and the maximum concentration was 12micrograms per liter. The Dove Creek area is unique compared to other study areas of the National Irrigation Water Quality Program becauseselenium concentrations probably are indicative of initial leaching conditions in a newly irrigated area.Selenium concentrations in nine shallow soil samples from the Dove Creek area ranged from 0.13 to 0.20 micrograms per gram. Selenium concentrations in bottom sediment from six ponds were less than the level of concern for fish and wildlife of 4 micrograms per gram. Many biota samples collected in the Dove Creek area had elevated selenium concentrations when compared to various guidelines and effect levels,although selenium concentrations in water, soil, and bottom sediment were relatively low. Selenium concentrations in 12 of 14 aquatic-invertebratesamples from ponds exceeded 3 micrograms per gram dry weight, a dietary guideline for protection of fish and wildlife. The mean seleniumconcentration of 10.3 micrograms per gram dry weight in aquatic bird eggs exceeded the guideline for reduced hatchability of 8 micrograms per gramdry weight. Two ponds in the Dove Creek area had a high selenium hazard rating based on a new protocol for assessing selenium hazard in theenvironment; however, waterfowl were reproducing at the two ponds. Three tributary streams of Mc Elmo Creek that drain irrigated areas of the Montezuma Valley south of the creek were sampled in 1994. Mud Creek probably is the largest source of selenium to Mc Elmo Creek. Most biota samples from Mud Creek had elevated selenium concentrations when compared to guidelines for dietary items and freshwater fish. Selenium concentrations in water samples collected in the Mancos River Basin upstream from Navajo Wash, which includes the Mancos Project, ranged from less than 1 to 10 micrograms per liter. Mud Creek contributed about 74 percent of the selenium load to the upper Mancos River in March 1994.Selenium concentrations were much higher in Navajo Wash; a sample collected in March had 97 micrograms per liter of selenium. Bottom-sediment samples from two ponds in the Mancos Projectexceeded the concentration of concern of 4 micrograms per gram. The highest selenium concentrations in biota samples from streams in the Mancos River Basin were for samples from Navajo Wash. Mostconcentrations in biota in the upper Mancos River Basin were less than guidelines. Mean selenium concentrations in eggs from aquatic birds collected at three ponds in the Mancos Project slightly exceed the guideline associated with reduced hatchability.Five bird livers had a mean selenium concentration of 32.6 micrograms per gram dry weight, whichslightly exceeded the mean concentration of 30 micrograms per gram dry weight that is associated with reproductive impairment. Two of the pondshad a high selenium hazard rating; however, mallard reproduction was observed in 1994 at one of the ponds that had a high selenium-hazard rating.

Colorado↗
USGS1996

Detailed study of selenium and other constituents in water, bottom sediment, soil, alfalfa, and biota associated with irrigation drainage in the Uncompahgre Project area and in the Grand Valley, west-central Colorado, 1991-93

In 1985, the U.S. Department of the Interior began a program to study the effects of irrigation drainage in the Western United States. These studies were done to determine whether irrigation drainage was causing problems related to human health, water quality, and fish and wildlife resources. Results of a study in 1991-93 of irrigation drainage associated with the Uncompahgre Project area, located in the lower Gunnison River Basin, and of the Grand Valley, located along the Colorado River, are described in this report. The focus of the report is on the sources, distribution, movement, and fate of selenium in the hydrologic and biological systems and the effects on biota. Generally, other trace- constituent concentrations in water and biota were not elevated or were not at levels of concern. Soils in the Uncompahgre Project area that primarily were derived from Mancos Shale contained the highest concentrations of total and watrer-extractable selenium. Only 5 of 128 alfalfa samples had selenium concentrations that exceeded a recommended dietary limit for livestock. Selenium data for soil and alfalfa indicate that irrigation might be mobilizing and redistributing selenium in the Uncompahgre Project area. Distribution of dissolved selenium in ground water is affected by the aqueous geochemical environment of the shallow ground- water system. Selenium concentrations were as high as 1,300 micrograms per liter in water from shallow wells. The highest concentrations of dissolved selenium were in water from wells completed in alluvium overlying the Mancos Shale of Cretaceous age; selenium concentrations were lower in water from wells completed in Mancos Shale residuum. Selenium in the study area could be mobilized by oxidation of reduced selenium, desorption from aquifer sediments, ion exchange, and dissolution. Infiltration of irrigation water and, perhaps nitrate, provide oxidizing conditions for mobilization of selenium from alluvium and shale residuum and for transport to streams and irrigation drains that are tributary to the Gunnison, Uncompahgre, and Colorado Rivers. Selenium concentrations in about 64 percent of water samples collected from the lower Gunnison River and about 50 percent of samples from the Colorado River near the Colorado-Utah State line exceeded the U.S. Environmental Protection Agency criterion of 5 micrograms per liter for protection of aquatic life. Almost all selenium concentrations in samples collected during the nonirrigation season from Mancos Shale areas exceeded the aquatic-life criterion. The maximum selenium concentrations in surface-water samples were 600 micrograms per liter in the Uncompahgre Project area and 380 micrograms per liter in the Grand Valley. Irrigation drainage from the Uncompahgre Project and the Grand Valley might account for as much as 75 percent of the selenium load in the Colorado River near the Colorado-Utah State line. The primary source areas of selenium were the eastern side of the Uncompahgre Project and the western one-half of the Grand Valley, where there is extensive irrigation on soils derived from Mancos Shale. The largest mean selenium loads from tributary drainages were 14.0 pounds per day from Loutsenhizer Arroyo in the Uncompahgre Project and 12.8 pounds per day from Reed Wash in the Grand Valley. Positive correlations between selenium loads and dissolved-solids loads could indicate that salinity-control projects designed to decrease dissolved-solids loads also could decrease selenium loads from the irrigated areas. Selenium concentrations in irrigation drainage in the Grand Valley were much higher than concentrations predicted by simple evaporative concentration of irrigation source water. Selenium probably is removed from pond water by chemical and biological processes and incorporated into bottom sediment. The maximum selenium concentration in bottom sediment was 47 micrograms per gram from a pond on the eastern side of the Uncompahgre Project.

Water-Resources Investigations Report↗
USGS1995

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Dolores Project area, southwestern Colorado and southeastern Utah, 1990-91

Water, bottom-sediment, and biota samples were collected in 1990-91 to identify water-quality problems associated with irrigation drainage in the Dolores Project area. Concentrations of cadmium, mercury, and selenium in some water samples exceeded aquatic-life criteria. Selenium was associated with irrigaton drainage from the Dolores Project, but other trace elements may be transported into the area in the irrigation water supply. Selenium concentrations exceeded the chronic aquatic-life criterion in water samples from lower McElmo Creek and Navajo Wash, which drain the Montezuma Valley, from newly irrigated areas, and from the Mancos River. The maximum selenium con- centration in water was 88 micrograms per liter from Navajo Wash. Concentrations of herbicides in water were less than concentrations harmful to aquatic life. Selenium concentrations in four bottom-sediment samples exceeded the baseline concentrations for soils in the Western United States. The largest selenium concentrations in biota were in samples from Navajo Wash, from newly irrigated areas north of the Montezuma Valley, and from the Mancos River basin. Selenium concentrations in aquatic-invertebrate samples from the newly irrigated areas exceeded a guideline for food items consumed by fish and wildlife. Selenium concen- trations in whole-body suckers were larger in the San Juan River downstream from the Dolores Project than upstream from the project at Four Corners. Selenium concentrations in fathead minnow samples from two sites were at adverse-effect levels. Mercury concentrations in warm-water game fish in reservoirs in the study area may be of concern to human health. Some concentrations of other trace elements exceeded background concentrations, but the concentrations were not toxicologically significant or the toxicologic significance is not known.

Water-Resources Investigations Report↗
USGS1994

Physical, chemical, and biological data for detailed study of irrigation drainage in the Uncompahgre Project area and in the Grand Valley, west-central Colorado, 1991-92

Because of concerns about potential effects of irrigation drainage on fish and wildlife resources and on human health, the U.S. Department of the Interior initiated a program in 1985 to assess water-quality problems associated with Federal irrigation projects in the Western United States. Physical, chemical, and biological data were collected for a detailed study of irrigation drainage in the Uncompahgre Project area and in the Grand Valley, west-central Colorado, during 1991-92. This report lists onsite measurements and concen- trations of major constituents, trace elements, and stable isotopes for surface-water- and ground-water-sampling sites. Insecticide data collected in the Grand Valley are presented. Ranges of specific-conductance measurements and dissolved- oxygen concentrations for selected wells and a daily record of water-level altitude and specific conduc- tance for a well in the Grand Valley are presented. The report presents historical water-level and dissolved-solids data for two wells in the Grand Valley. Concentrations of trace elements, major constituents, total carbon, and organic carbon in bottom-sediment, bedrock, and in aquifer-sediment samples and semiquantitative data on clay and bulk mineralogy of samples of the Mancos Shale are presented. The report contains selenium-speciation data for selected water and bottom-sediment samples and selected aquifer-test results. Biological samples collected in the Uncompahgre Project area and in the Grand Valley included aquatic plants, aquatic invertebrates, fish, birds, and bird eggs. The report lists concentrations of trace elements in biological samples collected in 1991-92. A limited number of biological samples were analyzed for pesticides, PCB's, and polycyclic aromatic hydrocarbons.

Open-File Report↗
USGS1993

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Pine River Project area, Southern Ute Indian Reservation, southwestern Colorado and northwestern New Mexico, 1988-89

During 1988-89, water, bottom sediment, biota, soil, and plants were sampled for a reconnaissance investigation of the Pine River Project area in southwestern Colorado. Irrigation drainage does not seem to be a major source of dissolved solids in streams. Concentrations of manganese, mercury, and selenium exceeded drinking-water regulations in some streams. The maximum selenium concentration in a stream sample was 94 microg/L in Rock Creek. Irrigation drainage and natural groundwater are sources of some trace elements to streams. Water from a well in a nonirrigated area had 4,800 microg/L of selenium. Selenium concentrations in soil on the Oxford Tract were greater in areas previously or presently irrigated than in areas never irrigated. Some forage plants on the Oxford Tract had large selenium concentrations, including 180 mg/km in alfalfa. Most fish samples had selenium concentrations greater than the National Contaminant Biomonitoring Program 85th percentile. Selenium concentrations in aquatic plants, aquatic inverte- brates, and small mammals may be of concern to fish and wildlife because of possible food-chain bioconcentration. Selenium concentrations in bird samples indicate selenium contamination of biota on the Oxford Tract. Mallard breasts had selenium concentrations exceeding a guideline for human consumption. The maximum selenium concentration in biota was 50 microg/g dry weight in a bird liver from the Oxford Tract. In some fish samples, arsenic, cadmium, copper, and zinc exceeded background concentrations, but concentrations were not toxic. Mercury concentrations in 16 fish samples exceeded the background concentration. Ten mercury concentrations in fish exceeded a guideline for mercury in food for consumption by pregnant women.

Colorado↗