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M. F. Hult

Publications and source records attributed to M. F. Hult.

At least 19 recordsLinked to original sources
USGS2006

Degradation of phenolic contaminants in ground water by anaerobic bacteria: St. Louis Park, Minnesota

Coal-tar derivatives from a coal-tar distillation and wood-treating plant that operated from 1918 to 1972 at St. Louis Park, Minnesota contaminated the near-surface ground water. Solutions of phenolic compounds and a water-immiscible mixture of polynuclear aromatic compounds accumulated in wetlands near the plant site and entered the aquifer. The concentration of phenolic compounds in the aqueous phase under the wetlands is about 30 mg/1 but decreases to less than 0.2 mg/1 at a distance of 430 m immediately downgradient from the source. Concentrations of naphthalene (the predominant polynuclear compound in the ground water) and sodium (selected as a conservative tracer) range from about 20 mg/1 and 430 mg/1 in the aqueous phase at the source to about 2 mg/1 and 120 mg/1 at 430 m downgradient, respectively. Phenolic compounds and naphthalene are disappearing faster than expected if only dilution were occurring. Sorption of phenolic compounds on aquifer sediments is negligible but naphthalene is slightly sorbed. Anaerobic biodegradation of phenolic compounds is primarily responsible for the observed attenuation. Methane was found only in water samples from the contaminated zone (2-20 mg/1). Methane-producing bacteria were found only in water from the contaminated zone. Methane was produced in laboratory cultures of contaminated water inoculated with bacteria from the contaminated zone. Evidence for anaerobic biodegradation of naphthalene under either field or laboratory conditions was not obtained.

Minnesota↗
USGS1994

Crude-oil spill research project near Bemidji, Minnesota - Bibliography, 1984-1994

The U.S. Geological Survey began a research project at the site of a crude-oil spill near Bemidji, Minnesota in 1983. The project is part of the U.S. Geological Survey's Toxic Substances Hydrology Program. The objectives of research at the site are to obtain an understanding of the mobilization, transport, and fate of petroleum derivatives in the shallow subsurface and to use this understanding to develop predictive models of contaminant behavior. This report presents a bibliography of scientific papers that have been published from 1984 to early 1994. Research results have been published in scientific journals, conference proceedings, U.S. Geological Survey Reports, and academic theses.

Open-File Report↗
USGS1993

Crude oil in a shallow sand and gravel aquifer—I. Hydrogeology and inorganic geochemistry

Changes in the distribution of inorganic solutes in a shallow ground water contaminated by crude oil document a series of geochemical reactions initiated by biodegradation of the oil. Upgradient of an oil body floating on the water table, oxidation of oil to carbonic acid dissolves carbonate minerals in the aquifer matrix. In this oxidized zone pH is depressed ∼1 pH unit, and the concentrations of Ca, Mg and HCO 3 − increase to more than twice that of the native ground water. In the anoxic zone beneath the oil body concentrations of dissolved SiO 2 , Sr, K, Fe and Mn increase significantly. Here, Fe is mobilized by microbial reduction, pH is buffered by the carbonate system, and silicates weather via hydrolysis and organic-acid-enhanced dissolution. Farther down-gradient the ground water is reoxygenated and Fe precipitates from solution, possibly as iron hydroxide or iron carbonates, while SiO 2 precipitates as amorphous silica. Other solutes, such as Mg, are transported more conservatively down-gradient where contaminated and native ground water mix. The observed changes in inorganic aqueous chemistry document changes in water-mineral interactions caused by the presence of an organic contaminant. These organic-initiated interactions are likely present in many contaminated aquifers and may be analogous to interactions occurring in other organic-rich natural waters.

Minnesota↗
USGS1993

Hydrogeologic data collected from a crude-oil spill site near Bemidji, Minnesota, 1983-91

The U.S. Geological Survey began a research project at the site of a crude oil spill near Bemidji, Minnesota in 1983. The project is part of the U.S. Geological Survey's Toxic Substances Hydrology Program. The objectives of research at this site are to obtain an understanding of the mobilization, transport, and fate of petroleum derivatives in the shallow subsurface and to use this understanding to develop predictive models of contaminant behavior. This report presents location and altitude data for selected features at the research site, water and oil level records from observation wells collected from 1983 through 1991, geologic logs from 45 observation wells and test holes, particle-size distribution data from 45 observation wells and test holes, and precipitation records from 1948 through 1991.

Minnesota↗
USGS1985

Partitioning studies of coal-tar constituents in a two-phase contaminated ground-water system

Organic compounds derived from coal-tar wastes in a contaminated aquifer in St. Louis Park, Minnesota, were identified, and their partition coefficients between the tar phase and aqueous phase were determined and compared with the corresponding n-octanol/water partition coefficients. Coal tar contains numerous polycyclic aromatic compounds, many of which are suspected carcinogens or mutagens. Groundwater contamination by these toxic compounds may pose an environmental health hazard in nearby public water-supply wells. Fluid samples from this aquifer developed two phases upon settling: an upper aqueous phase, and a lower oily-tar phase. After separating the phases, polycyclic aromatic compounds in each phase were isolated using complexation with N-methyl-2-pyrrolidone and identified by fused-silica capillary gas chromatography/mass spectrometry. Thirty-one of the polycyclic aromatic compounds were chosen for further study from four different classes: 12 polycyclic aromatic hydrocarbons, 10 nitrogen heterocycles, 5 sulfur heterocycles, and 4 oxygen heterocycles. Within each compound class, the tar/water partition coefficients of these compounds were reasonably comparable with the respective n-octanol/water partition coefficient.

Minnesota↗
USGS1985

Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota

A three-dimensional, ground-water-flow model of the Prairie du Chien-Jordan aquifer and associated hydrogeologic units was developed to evaluate the movement of coal-tar derivatives from a coal-tar distillation and wood-preserving plant in St. Louis Park, Minnesota. A finite-difference grid was superimposed on the modeled area, which includes most of eastern Hennepin County. The individual cells are 400-foot squares in the center of the grid (St. Louis Park area); the cells increase in dimension toward the outside limits of the grid. Five geologic units are represented by four layers in the model. These units include the Jordan Sandstone, the Prairie du Chien Group (dolomite and sandy dolomite), the basal confining unit of the St. Peter Sandstone (silty and sandy shale), the St. Peter Sandstone, and glacial deposits in bedrock valleys. The model was calibrated for steady-state conditions for a period before significant ground-water development (1885-1930) and for a period of significant pumping stress (winter conditions, 1970 fs). A transient calibration was accomplished by simulation of a period during which seasonal changes in potentiometric head in the Prairie du Chien-Jordan aquifer were significant (1977-80). Sensitivity testing indicated that leakage to the upper model layer and the vertical hydraulic conductivity of the basal confining unit of the St. Peter Sandstone were the model hydrologic properties which, when changed, resulted in the greatest changes in model-calculated water levels. The calibrated model generally calculates water levels that are within 10 feet of measured values. Model simulations indicate that the potentiometric surface of the Prairie du Chien-Jordan aquifer would be raised by as much as 3 feet in the area of the plant site by water introduced into the aquifer through wells open to more than one aquifer system. The cones of impression created at these wells could have a significant impact on the transport of contaminants in the Prairie du Chien-Jordan. The presence of coal-tar derivatives in the aquifer has been difficult to explain in wells located upgradient from the plant site to the north, west, and southwest. Simulations suggest that, during periods of heavy withdrawal from certain of these wells (SLP10, SLP15, and SLP5), local hydraulic gradients may have been altered, resulting in the potential for the movement of contaminants from the area of the plant site to the wells. Cones of impression at multiaquifer wells near the plant site contributed to the alteration of local gradients. Simulation of a proposed gradient-control plan, in which lateral homogeneity and isotropy of individual hydro geologic units was assumed, indicates that the actions would be effective in limiting expansion of the contaminated volume in the Prairie du Chien-Jordan aquifer. The plan includes the control of withdrawal from five wells. The simulations also show, however, that modelcalculated potentiometric surfaces are sensitive to changes in withdrawal rates at wells not intended to be under the control of the plan. Management of discharge from these wells also will be important to overall effectiveness of the remedial-action plan.

Minnesota↗
USGS1984

Assessment of ground-water contamination by coal-tar derivatives, St. Louis Park area, Minnesota

Operation of a coal-tar distillation and wood-preserving facility in St. Louis Park, Minnesota, during 1918-72 contaminated ground water with coal-tar derivatives and inorganic chemicals. Coal-tar derivatives entered the groundwater system through three major paths: (1) Spills and drippings that percolated to the water table, (2) surface runoff and plant process water that was discharged to wetlands south of the former plant site, and (3) movement of coal tar directly into bedrock aquifers through a multiaquifer well on the site. In the drift, Platteville, and St. Peter aquifers, ground water flows laterally from west to east and vertically downward. Near the former plant site, creosote-like organic fluids have migrated vertically downward through the drift and are being partially dissolved by ground water. Ground water has preferentially mobilized low-molecular-weight compounds such as phenolic compounds, alkyl-benzenes, and naphthalene, although polynuclear aromatic hydrocarbons as heavy as benzo(a)pyrene have been mobilized at low concentrations. Sorption of high-molecular-weight compounds has retarded their migration down the hydraulic gradient compared to low-molecular-weight compounds in the plume. Some simple phenolic compounds are being degraded to methane and carbon dioxide by bacteria under anaerobic conditions in the drift-PlattevilleSt. Peter aquifer system. Other low-molecular-weight aromatic compounds are apparently being degraded by aerobic bacteria at the periphery of the plume where oxygen is available. Intermediate degradation products such as volatile fatty acids are likely present, but complete conversion of the organic contaminants to innocuous inorganic substances has not been demonstrated. Near and south of 36th and Wooddale Avenues, contaminants enter the St. Peter aquifer where the Glenwood confining unit has been eroded in a buried bedrock valley. Contaminants previously entered the Prairie du Chien-Jordan aquifer through at least one multiaquif er well (W38). Other sources of contaminants and the low concentrations of contaminants hamper delineation of the maximum areal extent of contaminants that are resistant to biologic degradation. These biorefractory compounds will probably continue to migrate down the hydraulic gradients in the drift and Platteville and St. Peter aquifers. Of particular concern with respect to the health risk to humans are the polynuclear aromatic hydrocarbons, which are a major constituent of coal tar and are found in municipal wells near the site that are completed in the Prairie du Chien-Jordan aquifer. The Prairie du Chien-Jordan aquifer lies 250 to 500 feet below land surface and is relatively well protected from nearsurface sources of contamination by overlying rocks. However, the aquifer has been contaminated since at least 1932 because coal-tar derivatives have entered the aquifer through multiaquifer wells. The most significant single source of contamination in the aquifer is a well drilled on the site in 1917 (well W23) that has contained liquid coal-tar since at least 1958. The introduction, dissolution, and movement of this coal-tar in ground water has contaminated nearby municipal wells. The composition of the tar in well W23, and the ratio of concentrations of individual compounds in water from well W23 to those in municipal well SLP15, are consistent with known hydrologic, chemical, and biologic processes, and the conclusion that contaminants in well SLP15 are due primarily to contaminants introduced at well W23. Most of the major polynuclear aromatic hydrocarbons in the tar, although slightly soluble in water and strongly sorbed by aquifer materials, have moved greater distances at higher concentrations than have the lower-molecular-weight, more soluble compounds such as phenolic compounds and naphthalene. The latter are apparently being degraded by bacteria. The direction and rate of contaminant movement within the Prairie du Chien-Jordan aquifer changes with time because the ground-water-flow system continually adjusts to hydraulic stresses caused by ground-water withdrawals and flow through multiaquifer wells. Contaminants can move rapidly through the Prairie du Chien-Jordan because the upper part of the aquifer is a carbonate rock having fracture and solution-channel permeability, low effective porosity, and relatively small surface area for sorption. Consequently, the concentration and composition of contaminants in water pumped from individual industrial and municipal wells completed in the aquifer fluctuate with time. Although contaminants have been in the aquifer for at least 50 years and their spatial distribution is complex, concentrations remain highest near their points of introduction through multiaquifer wells near and on the site of the former plant. Contaminants reached the Ironton-Galesville aquifer through at least two deep multiaquifer wells (W23 and W38), but the extent of contamination in this aquifer, and in the underlying Mount Simon-Hinckley aquifer, is not known.

Minnesota↗
USGS1983

Ground-water contamination by organic bases derived from coal-tar wastes

A fluid sample from a shallow aquifer contaminated by coal-tar wastes was analyzed for organic bases. The sample consisted of a mixture of aqueous and oily-tar phases. The phases were separated by centrifugation and filtration. Organic bases were isolated from each phase by pH adjustment and solvent extraction. Organic bases in the oily-tar phase were further purified by neutral-alumina, micro-column adsorption chromatography. Separation and identification of the organic bases in each phase were achieved by using capillary gas chromatography-mass spectrometry-computer (GC-MS-COM) and probe distillation-high resolution mass spectrometry (PD-HRMS) techniques. Organic bases present in the aqueous phase included primary aromatic amines (such as aniline, alkylated anilines, and naphthylamines) as well as azaarenes (such as alkylated pyridines, quinolines, acridine, and benzoquinolines). The oily-tar phase contained acridine, benzacridines, dibenzacridines, and numerous other azaarenes, the elemental compositions of which were determined by PD-HRMS. Azaarenes in the oily-tar phase, varying in size from 6 to 12 rings, are reported for the first time. The origin and environmental significance of these compounds are discussed.

Environmental Toxicology and Chemistry↗
USGS1979

Water resources of the St. Louis River watershed, northeastern Minnesota

The St. Louis River is the largest tributary to Lake Superior in Minnesota. It drains a predominantly forested area of about 3,650 mi 2 (Minnesota Department of Conservation, 1959) and discharges into the lake at Duluth. The Mesabi Iron Range, noted for rich deposits of iron ore, parallels much of the northern watershed boundary. Large areas of land were altered by mining activities, as seen on the Landsat-1 MSS 7 images for September 26, 19744 (No. 1795-16203). The northeastward-trending string of water bodies along the northern boundary are flooded mine pits and tailings basins. The northeastern part of the watershed is largely State and National forest, whereas much of the southwestern and central parts are peat-covered wetlands. Generalized topographic features are shown on the map above. The topographic high along the northern boundary includes the Iron Range and is dissected by post-glacial drainage. The most notable drainage gap is that occupied by the Embarrass River. The series of southwestward-trending elongate hills in the eastern part of the watershed, visible on both the Landsat image and the topographic map, is the Toimi Drumlin Field (Wright, 1972). Topographically low, relatively flat land in the southwestern and central parts is a glacial lake plain. St. Louis River gradients are highly variable, being 9 ft/mi from its headwaters to the mouth of Partridge River, slightly more than 1 ft/mi from Partridge River to Cloquet, and 35 to 40 ft/mi in a 15-mi reach below Cloquest. The watershed is sparsely settled except for its northern and south-eastern parts. About 80 percent of the urban population lives on the Iron Range. Most of the suburban and rural residents alro live on or near the range or in the southeastern part of the watershed. Total population (1970), exclusive of those in the city of Duluth, which is included in the Lake Superior watershed (Olcott and others, 1976), was about 117,000.

Minnesota↗
USGS1976

Water resources of the Des Moines River Watershed, southwestern Minnesota

The Des Moines River drains about 1,350 square miles (3,496 km 2 ) of the north, west, and central parts of the watershed, and the East Fork Des Moines River along with several small creeks drain about 200 square miles (518 km 2 ) in the east part. These tributaries join the Des Moines river in Iowa. The watershed is on the Coteau des Prairies, the most prominent upland in southern Minnesota. the Coteau rises to altitudes of more than 1,900 feet (579 m) within the watershed. The west boundary is along the crest of the Coteau and was formed by a terminal moraine during late Wisconsin Glaciation. This moraine forms part of the divide between the Mississippi and Missouri Rivers. The north and east boundaries are also formed by morainic highs which represent recessions of the Des Moines lobe during late Wisconsin Glaciation. Surficial materials consist mostly of clayey drift with a few surficial outwash (sand and gravel) areas near the streams. Topographic quadrangle maps published by the U.S. Geological Survey are available for the entire watershed.

Minnesota↗
USGS1975

Water resources of the Zumbro River watershed, southeastern Minnesota

The Zumbro River drains 1,428 square miles and falls from about 1,300 feet altitude in its headwaters to 665 feet at its mouth. The remaining 248 square miles included in the watershed is drained by small creeks flowing directly into the Mississippi River. Distribution of water use is about as follows: domestic, 50 percent; farm (for irrigation and livestock), 18 percent; and industrial, 32 percent. Total usage, in water-budget terms, is 0.24 inch over the entire watershed, or less than 1 percent of inflow (average annual precipitation). Total quantity of water, thus, is of lesser concern than local availability and quality of water. The dominant ions (calcium, magnesium, and bicarbonate) and dissolved solids are reduced by dilution during periods of high water discharge in the Zumbro River at Zumbro Falls. Similarly, in the South Fork Zumbro River near Rochester, dominant ions, dissolved solids, and those ions that are increased by waste disposal (sodium, chloride, and nitrates) are all reduced by dilution at high water discharge. For the Zumbro River the smallest monthly range and the most uniform daily mean discharge usually occurs in January, whereas the greatest range usually occurs in March. The lowest flows usually occur in the winter and the highest during the spring ice breakup. The lowest observed flow, 47 cfs, occurred on February 18, 1961 and the highest, 23,600 cfs, occurred on March 29, 1962. Seventeen of 22 municipalities obtain at least part of their water supply from the Prairie du Chien-Jordan aquifer. Although only one town uses the Galena aquifer, a large number of private domestic wells are completed in it in the western part of the watershed. (Woodard-USGS)

Minnesota↗
USGS1975

Water resources of the Cedar River watershed, southeastern Minnesota

The Cedar River Watershed Unit (as established by the states of Minnesota) consists of 1,204 square miles (3,118 square kilometres) of flat or gently undulating plain. The watershed is drained by the Cedar River and several smaller streams that flow south into Iowa and eventually into the Mississippi River. Its easternmost neck is part of a broad, flat, well-drained plain, covered by a thin sheet of glacial drift. Sinkholes have formed in the near surface carbonate bedrock, and a karst topography is developing. Farther north, along the east boundary, the drift is more than 200 feet (61 m) thick, and the land surface reaches altitudes of more than 1,450 feet (442 m) – the highest area in southeastern Minnesota. In the central part of the watershed in the southern flood plain of the Cedar River, the drift is less than 100 feet (30 m) thick, and the land surface altitude is less than 1,140 feet (347 m). The western part is dominated by a terminal moraine of the last Wisconsin glacier. Here the drift is more than 300 feet (91 m) thick, is poorly drained, and has numerous lakes. The watershed is mostly prairie and is well suited for farming, which is the dominant economic activity. Topographic quadrangle maps published by the U.S. Geological Survey are available for the entire watershed.

Minnesota↗