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Research about Minnesota

Source-linked reports with geographic coverage including Minnesota.

At least 595 records · Page 33Linked to original sources
USGS1991

Hydrology, water quality, and simulation of ground-water flow at a taconite-tailings basin near Keewatin, Minnesota

Taconite tailings, a waste product from processing of iron ore, have been deposited in a 2.5-square-mile containment basin near Keewatin, Minnesota, The basin, which is bounded by earthen dikes of compacted drift and clayey bouldery till, contains saturated tailings consisting of chert and other silica-rich particles that range from clay to coarse-sand size. Runoff from the tailings is slight and occurs only after heavy rains and snowmelt. Average discharge from the basin from April 1982 through June 1984 was about 0.6 cubic foot per second. Instantaneous discharge ranged from zero during much of the period to about 140 cubic feet per second following snowmelt in spring 1982. Daily mean discharge from the basin exceeded 20 cubic feet per second on two days during the period of study. Water levels in wells range from 0 to 25 feet below the tailings surface; seasonal fluctuations range from 2 to 8 feet. Ground water flows radially from a mound in the north-central part of the basin under a hydraulic gradient of 4.7 x 10 -3 feet per foot. Vertical flow also is downward to drift deposits beneath the tailings. Vertical gradients range from 7.0 x 10 -3 to 6.0 x 10 -1 feet per foot. Saturated thickness of the tailings ranges from about 1 to 35 feet. Estimated horizontal hydraulic conductivity ranges from about 1 to 500 feet per day. Transmissivities range from about 25 feet squared per day in fine tailings to about 350 feet squared per day in coarse tailings. Ground-water recharge from precipitation was 11.8 inches from October 1982 through September 1983. Ground-water outflow as leakage to the underlying drift deposits was 9.9 inches for the same period. Water collected from wells completed in the tailings and from the drainage ditch at the basin outlet is of a mixed type in which the magnesium concentration only slightly exceeds concentrations of calcium and sodium plus potassium, expressed in milliequivalents, and concentrations of sulfate and bicarbonate, expressed in milliequivalents, are equal. Concentrations of arsenic, fluoride, and nitrite plus nitrate in water from the tailings were notably greater than in water from adjacent aquifers. However, only fluoride, manganese, and nitrite plus nitrate concentrations equalled or exceeded State drinking-water standards. Suspended-sediment concentrations in streamflow ranged from less than 1 milligram per liter during low-flow periods to about 4,600 milligrams per liter following snowmelt in the spring of 1982. Numerical-model simulations of ground-water flow near the vicinity of the tailings basin indicate that, if areal recharge were doubled during spring and fall, water levels in wells could average about 4 feet above 1983 levels during these periods. Model results indicate that water levels in the tailings could possibly remain about 5 feet above 1983 levels at the end of the year. Water levels in the tailings at the outlet of the basin could be about 1 foot above 1983 levels during the spring stress period and could be nearly 1.5 feet above 1983 levels during the fall stress period. Under these hypothetical climatic conditions, ground-water contribution to discharge at the outlet could be about 50 cubic feet per second during spring and about 80 cubic feet per second during fall.

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USGS1991

Hydrogeology and water quality of glacial-drift aquifers in the Bemidji-Bagley area, Beltrami, Clearwater, Cass, and Hubbard Counties, Minnesota

Unconfined and the upper confined aquifers in glacial drift are the primary sources of water in a 1,600 square-mile area including parts of Beltrami, Cass, Clearwater, and Hubbard Counties, Minnesota. The unconfineddrift aquifer consists of coarse sand and gravel in the center of the study area. The total area underlain by the unconfined-drift aquifer is approximately 550 square miles. The unconfined aquifer ranges in thickness from 0 to 130 feet, and is greater than 20 feet thick over an area of 280 square miles. On the basis of scant data, the transmissivity of the unconfined aquifer ranges from less than 70 feet squared per day in the south and west to greater than 8,900 feet squared per day in an area west of Bemidji. Well yields from 10 to 300 gallons per minute are possible in some areas. The unconfined and upper confined-drift aquifers are separated by a fine-grained confining unit of till or lake deposits. The thickness of the upper confined-drift aquifer ranges from 0 to 60 feet in the Bemidji area. On the basis of specific-capacity and aquifer-thickness data, and results of model simulations, the transmissivity of the upper confined-drift aquifer ranges from less than 100 feet squared per day in the south and west parts of the aquifer to about 12,800 feet squared per day in the area around Bemidji. Well yields of 10 to 2,100 gallons per minute are possible in some areas. The direction of ground-water flow in both unconfined and upper confineddrift aquifers is toward the Mississippi and Clearwater Rivers. These rivers are the major discharge points for both aquifers. Ground-water divides, which separate the ground-water flow systems that discharge to these rivers, are approximately coincidental with surface-water divides between the rivers. Water from both aquifers generally is of the calcium bicarbonate type and is very hard, averaging 309 and 267 milligrams per liter as CaCO 3 from confined and unconfined-drift aquifers, respectively. Water from both aquifers generally is suitable for drinking, crop irrigation, and most other uses. Concentrations of ammonia, boron, chromium, iron, manganese, and phenols, however, locally exceed recommended limits for drinking water (Minnesota Pollution Control Agency, 1988). Longer residence time and leakage through glacial till is believed to cause higher concentrations of common inorganic constituents in water from confined-drift aquifers than concentrations in water from the unconfined-drift aquifer. Elevated concentrations of nutrients, chloride, and phenols in the unconfined-drift aquifer may be related to land-use practices. Statistical comparisons of common chemical constituents in water from wells completed in the unconfined-drift aquifer in several land-use areas suggest that concentrations of many constituents and physical properties are generally greater for wells in areas of commercial and residential land-use than for wells in areas of agriculture or forest land-use. These constituents include ammonia plus organic nitrogen, phosphorus, calcium, sodium, potassium, chloride, sulfate, silica, dissolved solids, and specific conductances. The mean values of ammonia nitrogen, magnesium, and fluoride are generally greater for wells in commercial land-use type areas than for wells in forested and agricultural land-use type areas. The mean concentration of nitrogen (N0 2 + NO 3 , dissolved) is generally greater for wells in residential land-use type areas than for wells in forested and agricultural land-use type areas. The Kruskil-Wallis test, a nonparametric that for 12 of the 21 constituents sampled in groups in the unconfined-drift aquifer, a of these constituents and land use was found statistical technique, indicated common in all land-use type relation between the concentration to be statistically significant.

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USGS1991

Hydrogeology and simulation of ground-water flow in the Rochester area, southeastern Minnesota, 1987-88

Ground-water flow in the St. Peter-Prairie du Chien-Jordan aquifer was studied in a 700 square-mile area surrounding Rochester, Minnesota. The aquifer consisting of sandstone, limestone, and dolomite is locally confined by the Decorah-Platteville-Glenwood sequence of shales and limestones. Regional flow in the aquifer is from a ground-water divide on the western, southern, and eastern sides of the city toward various rivers. A 140-square-mile area of the aquifer is a source of water supply for the Rochester area. A cone of depression in the potentiometric surface of the aquifer throughout most of the year is centered around high-capacity (greater than about 200 gallons per minute) wells in downtown Rochester. The cone covered an area of about 2.3 square miles in August 1988. Most streams in the area gain water from the ground-water system. One reach of the South Fork Zumbro River, however, loses water to the system. This loss is probably caused by the pumping of nearby high-capacity wells. A ground-water-flow model was used to simulate the effects of an extended drought near Rochester. Conclusions based on the simulations are that (1) reduced recharge and increased pumping, conditions that could exist during a 3-year drought, would probably lower water levels 5 to 10 feet regionally and more than 30 feet in the city; (2) pumping of six additional municipal wells on the perimeter of the city would lower regional water levels about 1 to 5 feet; and (3) that water levels would recover 1 to 18 feet if pumping from six municipal wells in downtown Rochester were discontinued. The area encompasses five recharge zones that can be delineated on the basis of recharge rate. About 54 percent of recharge to the aquifer in the area contributing water to Rochester is from a zone along the edge of the Decorah-Platteville-Glenwood confining unit. About 10 percent of recharge in this contributing area is to the sewered area of Rochester.

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USGS1991

Water resources of the Red Lake Indian Reservation, northwestern Minnesota

This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the Red Lake Indian Reservation Tribal Council, to evaluate the water resources of the contiguous Red Lake Indian Reservation. Water resources of the contiguous Red Lake Indian Reservation meet the present (1989) needs for potable supply and other household uses. In addition, they provide ecological, recreational, and aesthetic benefits. Mean annual precipitation in the study area is 22.7 inches. Approximately 90 percent of this precipitation returns to the atmosphere by evapotranspiration; the remainder becomes runoff. Some of the precipitation that contributes to evapotranspiration and runoff initially infiltrates the land surface and recharges the ground-water reservoir. The net recharge to ground water generally ranges from roughly 0.5 to 1.35 inches per year. Assuming negligible long-term changes in the amount of ground water in storage, the recharge to and discharge from the ground-water reservoir balance each other over time. Glacial-drift aquifers are the source of ground water in the Red Lake Indian Reservation. The most significant sources of ground-water supply are confined glacial-drift aquifers, which are discontinuous lenses of sand and gravel 50 to 150 feet below land surface. Estimated yields of wells completed in these aquifers range from approximately 20 to 240 gallons per minute. Lower and Upper Red Lakes, which extend over one fourth of the study area, are the largest surface-water bodies. The study area also includes streams and many smaller lakes. Most of the streams drain into Lower and Upper Red Lakes, and the lakes discharge into the Red Lake River. Spring snowmelt generally causes peak flows in the streams. Low-flow conditions commonly occur during midsummer to early fall and winter. The quality of ground water is suitable for drinking and other household uses, and the quality of the surface water generally meets U.S. Environmental Protection Agency criteria necessary for the maintenance of aquatic life. The major ions in both ground and surface water are calcium, magnesium, and bicarbonate. Lower and Upper Red Lakes are eutrophic to mesotrophic on the basis of their summer Secchi disk-transparency readings, which ranged from 2.6 to 8.2 feet. The concentration of total organic carbon in samples from Lower and Upper Red Lakes and four streams were below or, in the case of one stream, about equal to 30 milligrams per liter, which is indicative of water little affected by human activities. The sample with the highest organic carbon content was collected from a stream that drained peatlands, which were probably sources of organic matter in the runoff. The concentration of nitrite plus nitrate in samples collected from Lower and Upper Red Lakes in late summer was below 0.01 milligrams per liter, which is characteristic of water uncontaminated by animal wastes. Total phosphorus in these samples ranged from 0.01 to 0.02 milligrams per liter. Most of this phosphorus was in the particulate organic fraction because of the abundance of phytoplankton.

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USGS1991

Gray wolf density and its association with weights and hematology of pups from 1970 to 1988

We examined weights and hematologic profiles of gray wolf ( Canis lupus ) pups and the associated wolf density in the east-central Superior National Forest of northeastern Minnesota (USA) during 1970 to 1988. We collected weight and hematologic data from 117 pups (57 females, 60 males) during 1 September to 22 November each year. The wolf density (wolves/800 km 2 ) trend was divided into three phases: high (72 ± 7), 1970 to 1975; medium (44 ± 2), 1976 to 1983; and low (27 ± 2), 1984 to 1988. Wolf numbers declined ( P = 0.0001) 39 and 63% from 1970 to 1975 to 1976 to 1983 and from 1970 to 1975 to 1984 to 1988, respectively. Weight was similar between male and female pups and did not vary as wolf density changed. Mean hemoglobin ( P = 0.04), red ( P = 0.0001) and white blood cells ( P = 0.002), mean corpuscular volume, mean corpuscular hemoglobin concentration and mean corpuscular hemoglobin ( P = 0.0001) did differ among the multi-annual phases of changing wolf density. Weight and hematologic data also were compared to values from captive wolf pups. The high, but declining wolf density was associated with macrocytic, normochromic anemia in wolf pups, whereas the lowest density coincided with a hypochromic anemia. Although hematologic values show promise for assessing wolf pup condition and wolf population status, they must be used cautiously until data are available from other populations.

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USGS1990

Transformation of Monoaromatic hydrocarbons to organic acids in anoxic groundwater environment

The transformation of benzene and a series of alkylbenzenes was studied in anoxic groundwater of a shallow glacial-outwash aquifer near Bemidji, Minnesota, U.S.A. Monoaromatic hydrocarbons, the most water-soluble components of crude oil, were transported downgradient of an oil spill, forming a plume of contaminated groundwater. Organic acids that were not original components of the oil were identified in the anoxic groundwater. The highest concentrations of these oxidized organic compounds were found in the anoxic plume where a decrease in concentrations of structurally related alkylbenzenes was observed. These results suggest that biological transformation of benzene and alkylbenzenes to organic acid intermediates may be an important attenuation process in anoxic environments. The transformation of a complex mixture of hydrocarbons to a series of corresponding oxidation products in an anoxic subsurface environment provides new insight into in situ anaerobic degradation processes.

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USGS1990

Field testing of commercially manufactured capture collars on white-tailed deer

We conducted 31 tests of commercially manufactured capture collars on female white-tailed deer ( Odocoileus virginianus ) in the Superior National Forest, Minnesota, under temperatures from -37C to 22C. Deer were recaptured in 28 of the 31 tests; in the 3 failures, we remotely released the collars from the deer. Communication with the collars was achieved from up to 3.0 km on the ground and 26.5 km from the air.

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USGS1990

Minimizing capture-related stress on white-tailed deer with a capture collar

We compared the effect of 3 capture methods for white-tailed deer ( Odocoileus virginianus ) on blood indicators of acute excitement and stress from 1 February to 20 April 1989. Eleven adult females were captured by Clover trap or cannon net between 1 February and 9 April 1989 in northeastern Minnesota. These deer were fitted with radio-controlled capture collars, and 9 deer were recaptured 7-33 days later. Trapping method affected serum cortisol (P < 0.0001), hemoglobin (Hb) (P < 0.06), and packed cell volume (PCV) (P < 0.07). Cortisol concentrations were lower (P < 0.0001) in capture-collared deer (0.54 ± 0.07 [SE] μg/dL) compared to Clover-trapped (4.37 ± 0.69 μg/dL) and cannon-netted (3.88 ± 0.82 μg/dL) deer. Capture-collared deer were minimally stressed compared to deer captured by traditional methods. Use of the capture collar should permit more accurate interpretation of blood profiles of deer for assessement of condition and general health.

Minnesota↗
USGS1990

Effects of winter undernutrition on body composition and physiological profiles of white-tailed deer

We examined the effects of undernutrition and recovery on body composition and blood and urinary profiles of 6 captive white-tailed deer ( Odocoileus virginianus ) between 18 December 1984 and 3 May 1985. Deer were weighed, and blood and urine were collected every 2 weeks from 10 January to 3 May. At Weeks 2, 8, and 14, body composition was estimated by the dilution of tritiated water technique and standard predictive equations. Feed intake decreased and cumulative mass loss increased during nutritional restriction. Baseline body composition included 62.1 ± 0.9 (SE)% water, 11.9 ± 1.0% fat, 20.5 ± 0.7% protein, and 4.5 ± 0.0% ash. Percent protein loss was linearly related (r 2 = 0.91, P < 0.001) to percent mass loss. Peak mass loss from the beginning of the study (12.8 ± 2.0%) occurred at Week 12; estimated protein loss was 12.5%. Fat reserves were 85% depleted from Week 2 to Week 14. Elevated packed cell volume (PCV), serum calcium (Ca), cholesterol, triglycerides, and cortisol; and diminished serum urea nitrogen, thyroxine (T4), urinary urea nitrogen: creatinine and potassium: creatinine were associated with reduced food intake, mass loss, and decreases in body water, fat, and protein. Altered values of most of these blood and urinary characteristics reflected initiation of nutritional recovery after nutrition improved. Sequential data collection and the use of a combination of indices in blood or urine will yield the most useful assessments of animal nutrition and condition.

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USGS1990

Hydrologic and water-quality data for streams and impoundments in the Coteau des Prairies-Upper Minnesota River basin, 1979-84

Water-quality and streamflow data were collected in the Coteau des Prairies region of southwestern Minnesota and eastern South Dakota from 1979- 84. Data were collected to (1) document the water-quality characteristics of streams and impoundments in the Coteau area, (2) predict the impact of proposed impoundments, (3) define the amount of dissolved and suspended material transported, and (4) determine the differences in water quality between the impoundment inflows and outflows. Streamflow and water-quality data were collected at 12 stream and four impoundment sites. Continuous-record gages, set to collect data at 15-minute intervals, and readings taken by local observers were used to complete discharge records at 10 stream sites and stage records at three impoundment sites. Automatic samplers and local observers collected storm runoff, sediment, and nutrient samples at 10 stream sites. Water-quality samples were collected at various time and stage intervals during high flow and periodically during low flow. Primary emphasis in the stream-sampling program was on analysis of samples for nutrients in 1980-82, and on analysis of suspended sediment and nutrients in 1983-84. Field measurements were made of pH, water temperature, dissolved oxygen, specific conductance, alkalinity, and bacteria. Secondary emphasis was on analysis of major dissolved substances. Primary emphasis in the impoundments was on analysis of samples for phosphorus and chlorophyll and on the measurement of transparency. Temperature and dissolved-oxygen concentrations were measured to determine the degree of stratification. All data collected during the study are given in tables 4-13 of this report. The tables list mean-daily stream discharge, mean-daily suspendedsediment concentration, daily suspended-sediment discharge, results of waterquality analyses, and bed-material particle-size analyses at stream sites. The tables also list information on pool stage, water temperature, and transparency, on dissolved-oxygen, chlorophyll a, phytoplankton, and nutrient concentrations, and on chemical and partical-size analyses of bed material at impoundment sites.

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USGS1990

Monthly mean discharge at and between selected streamflow-gaging stations along the Mississippi, Minnesota, and St. Croix rivers, 1932-87

Monthly mean discharges for the period of record are given for the streamflow-gaging stations along the upper Mississippi River from its headwaters to Prescott, Wisconsin, as well as for the first upstream streamflow-gaging station on the major tributaries of the Mississippi River, the Minnesota and St. Croix Rivers. Differences in the monthly mean discharge between selected upstream and downstream streamflow-gaging stations are given. The differences were calculated by subtracting the monthly mean discharge from the upstream streamflow-gaging station or stations from the downstream station. The difference is reported at the downstream streamflow-gaging station.

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USGS1990

Importance of return flow as a component of water use

Understanding the relation between the hydrologjc cycle and water use is important for effective water-resources management. The hydrologic cycle is the natural pathway of water from evaporation to precipitation to infiltration or runoff and to storage from which evaporation can again occur. The science of water use is the study of human influences on the hydrologic cycle. Human activities affect the hydrologic cycle by changing the quantity, distribution, and quality of available water. Quantifying return flow is useful to water managers in evaluating such changes. Return flow is often thought of as what runs down the drain, or what is leftover after the water's purpose has been served. As innocuous as that may sound, return flow plays a significant part in the overall water-use picture.

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USGS1990

Geohydrology and water quality of confined-drift aquifers in the Brooten-Belgrade area, west-central Minnesota

Confined-drift aquifers in six aquifer zones identified in a 1,300-square-mile area of west-central Minnesota near Brooten and Belgrade range in thickness from 5 to 110 feet. Transmissivities generally range from 500 to 10,000 feet squared per day, and theoretical well yields generally range from 100 to 900 gallons per minute. Regional ground-water flow in the confined-drift aquifers is to the southeast with local discharge to the East and Middle Branches of the Chippewa River, the North Fork Crow and Sauk Rivers, and to smaller streams, lakes, wetlands, and wells. Water levels near high-capacity pumped wells generally fluctuate 5 to 40 feet annually, compared to annual fluctuations of less than 5 feet in the unconfined aquifer. Water from confined-drift aquifers generally is suitable for most uses. The water is hard to very hard and contains locally elevated concentrations of iron, manganese, and dissolved solids. Results from a ground-water-flow model indicate that increased pumping from confined aquifers in the area would not adversely affect water levels. The addition of 10 to 20 hypothetical wells, pumping 123 to 246 million gallons per year, generally resulted in regional water-level declines of 0.1 to 1.0 feet. Simulations showed that the reduced recharge and increased pumping resulting from a 3-year drought probably would lower water levels between 5 and 10 feet regionally in the confined-drift aquifers and as much as 20 feet locally in the unconfined aquifer. Ground-water discharge to the East Branch Chippewa and North Fork Crow Rivers during the simulated drought would be reduced by 38 percent of 1984 conditions.

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USGS1990

Effects of present and projected ground-water withdrawals on the Twin Cities aquifer system, Minnesota

The Twin Cities aquifer system in Minnesota contains 5 aquifers and 4 confining units composed of 14 stratigraphic units. Bedrock aquifers consist of friable sandstones and highly fractured carbonate rocks; aquifers in the glacial drift consist of outwash and alluvium. From 1880 to 1980, groundwater withdrawals had caused long-term declines of water levels of as much as 90 feet in the Prairie du Chien-Jordan aquifer and 240 feet in the deeper Mount Simon-Hinckley aquifer--the two major sources of ground-water supplies in the area. A steady-state model of ground-water flow was used successfully to simulate the potentiometric surfaces of the aquifers during the 1970's. assuming a withdrawal rate of about 190 million gallons per day from the entire system. Projected changes in population and industrial development suggest that future ground-water withdrawals may increase from those for the 1970's. Steady-state model results indicate that the potentiometric surface of the Mount Simon-Hinckley aquifer would be lowered as much as 400 feet if pumpage from that aquifer were increased by 125 percent above 1980 ground-water withdrawal rates of about 200 million gallons per day. The potentiometric surface of the Prairie du Chien-Jordan aquifer also would be lowered as much as 400 feet if pumpage from that aquifer were increased by 200 percent above 1980 ground-water withdrawals of 160 million gallons per day. Given the projected distribution of future ground-water development, and the limitations inherent in simulating ground-water flow, the model results indicate that an approximate limit of ground-water availability in the Twin Cities Metropolitan Area, Minnesota, is from about 500 to 800 million gallons per day.

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