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921.
In 1991, a fire occurred at a foundry in western Pennsylvania. The fire started in capacitors that contained polychlorinated biphenyls (PCBs) and subsequent sampling has indicated that PCBs and products of their incomplete combustion, the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), were released as a result of the fire. This article develops and provides justification for site-specific cleanup levels for the PCBs, PCDDs, and PCDFs accidentally released into this industrial facility during the fire. Cleanup levels were calculated using standard risk assessment approaches and assumptions, and these riskbased values were compared with cleanup criteria used for other sites. Final criteria were established based on this comparison and a consideration of such site-specific factors as migration potential, industrial use patterns, and the small mass of material present. 相似文献
922.
Susan Power Bratton Raymond C. Mathews Jr. Peter S. White 《Environmental management》1980,4(5):433-448
Agricultural management in Cades Cove, an historic district in Great Smoky Mountains National Park, has affected natural resources both within the district and in the adjoining natural areas. Aquatic impacts of haying and cattle grazing included increases in water temperatures, turbidity, nutrient loading, and bacterial counts and decreases in benthic macroinvertebrate density and fish biomass. Wildlife populations, including groundhogs, wild turkeys, and white-tailed deer, have increased in the open fields and around the periphery of the historic district. Intensive deer foraging has removed deciduous seedlings and saplings from woodlots, lowering species diversity and favoring coniferous reproduction. Cades Cove has limestone habitats unique in the park, and both deer browse and cattle grazing may have disturbed populations of rare plant species. Effects on water quality are detectable at a campground 15 stream km from the agricultural area, and the effects of deer foraging extend about 1 km beyond the open fields.Since historic landscape preservation is presently a goal of the park, managing for open vistas in Cades Cove will require some sort of continuing disturbance. Conversion of cattle pastures to hayfields would reduce aquatic impacts but the deer herd might increase as a result of reduced competition for forage. Retarding old field succession would increase populations of native plant species dependent on sunlight, but would require government-funded mowing. Other options are discussed. Completely eliminating the effects of the historic district on adjoining areas may be impossible, at least under present economic constraints. 相似文献
923.
Peter E. Black 《Journal of the American Water Resources Association》1980,16(5):894-899
ABSTRACT: A method, adapted to an APL interactive terminal, is described which allows the operator to thoroughly search a large set of gaged watersheds in order to find sources of comparable hydrologic data for detailed analysis. Bases of the search - and inventory - include drainage basin size and elevation, and geographical and temporal parameters, and should enhance opportunities for more reliable use of existing data. 相似文献
924.
F. Harvey Dove Peter J. Schreuder 《Journal of the American Water Resources Association》1979,15(2):326-336
ABSTRACT: A visual selection technique can be utilized to locate potential well field sites prior to on-site testing. The technique is based upon an understanding of the regional hydrology and an appreciation for development goals such as the identification of high-yield and low-impact locations. Although the uniqueness of Pasco, Pinellas, and Hillsborough Counties in Western Florida has been incorporated into the current application, the methodology, with modifications, is transferable to other geographic regions. Overlays of each criterion used in site selection are combined to form a regional composite showing favorable site locations and further serve a useful communications role as visual aids during public presentation. Implications of direct and indirect cost savings to the public are obtained when the methodology is applied to the location of municipal well fields. 相似文献
925.
CHEAP POWER - AN EXPENSIVE FAILURE: HYDRO-ELECTRIC POWER AND INDUSTRIAL DEVELOPMENT IN NEWFOUNDLAND1
Peter Crabb 《Journal of the American Water Resources Association》1974,10(1):42-53
ABSTRACT By creating the 459,000 kW Bay d'Espoir h.e.p. scheme, the Newfoundland government hoped that the consequent doubling of the island's electricity supply would not only eliminate a deficite situation but provide power for industrial development. These hopes have not been fulfilled, and only one company, producing elemental phosphorus, was attracted to the island by the government's ‘cheap power’ policy. In addition to the continuing power subidy, this company received considerable federal and provincial incentives by locating its plant in Newfoundland. To these direct financial costs have to be added the environmental destruction and deterioration stemming from the h.e.p. development and the haste with which its construction was undertaken, and the catastrophic pollution problem created by effluent from the phosphorus plant. The costs of the ‘cheap power’ policy have been, and continue to be, massive for Newfoundland, Canada's poorest province. Further, the policy has made little or no impact on the small job market and the very large unemployment problem. 相似文献
926.
Larry C. Tennyson Peter F. Ffolliott David B. Thorud 《Journal of the American Water Resources Association》1974,10(6):1246-1254
ABSTRACT: The behavior of intercepted snow on a stand of uneven-aged ponderosa pine in east-central Arizona was evaluated with the use of a super 8-mm time lapse movie camera to determine the relative significance of snowfall interception in the water yield of this type forest. A snow load index was developed to estimate interception storage for two trees in the field of view for discrete time periods. The snow load index. photographs, and climatic data were combined to describe accumulation and to identify and rank according to relative magnitudes the basic processes of canopy snow removal. The rate of snow accumulation was nonlinear with initial storage being rapid. then slowing with time. Most of the intercepted snow eventually reached the snowpack on the ground by snowslide and wind erosion or by snowmelt and subsequent stemflow and drippmg of meltwater, and was therefore not considered a significant loss to the water budget on site. Some water apparently was disposed of by the evaporation of meltwater and sublimation of canopy snow, but these losses appeared to be comparatively minor. 相似文献
927.
928.
Peter W. Anderson Samuel D. Faust 《Journal of the American Water Resources Association》1972,8(4):750-760
ABSTRACT. New Jersey, together with other states in the northeast, was stricken with drought during 1961-66. The effect of this drought was most severe in the northern part of the State. The water quality of the Passaic River, which drains the urban, industrialized northeast, perhaps deteriorated the most among the major drainage systems. This river system is used as a raw-water source by 10 water suppliers. The impact of the drought upon the water supply of the Passaic Valley Water Commission, the most downstream of the basin's suppliers, which supplies an average of about 90 million gallons a day to more than 650,000 persons, is evaluated herein. The drought's impact on the raw-water quality is appraised by the comparison of before-and-after qualities of dissolved solids, dissolved oxygen, biochemical-oxygen demand, turbidity, and hardness. For example, at the worst point during the drought, monthly average dissolved-solids content in the raw water were about 210 percent, hardness, about 167 percent, and biochemical-oxygen demand about 270 percent higher than antecedent values. In general, the study concludes that the drought produced a deterioration in both raw and finished water quality, and is estimated to have increased chemical-treatment costs during the drought by about $650,000. 相似文献
929.
930.
John Richardson Peter A. Straub Katherine Carter Ewel Howard T. Odum 《Environmental management》1983,7(4):321-326
Sulfate-enriched water that was discharged experimentally into a floodplain forest in Florida caused H2S formation, and trees showed signs of stress within one year. Chloride-enriched water also caused trees to show signs of stress. Trees in this ecosystem may also be sensitive to changes in hydroperiod. 相似文献