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111.
This article presents a case history of hazardous waste landfill remediation activities at General Electric's Silicone's (GES's) manufacturing facility in Waterford, New York. The approach presented describes the development of the remedial program and its subsequent modification in achieving regulatory compliance goals, providing environmental benefit, and satisfying business considerations and budgetary constraints. 相似文献
112.
Alan C. Heyvaert John E. Reuter Charles R. Goldman 《Journal of the American Water Resources Association》2006,42(1):45-54
The Tahoe City Wetland Treatment System (TCWTS) was constructed in 1997 to treat stormwater runoff from 23 ha of commercial, highway, and residential land use in the Lake Tahoe Basin. This subalpine, constructed, surface flow wetland treatment system consists of two cells in series, with a design water surface area of about 0.6 ha. Water quality monitoring from October 2002 through September 2003 was conducted with autosamplers at the inflow and outflow sites during 24 sampling events, with a median duration of 53 hours, representing 42 percent of total inflow to this wetland during the year. Monitoring data indicate an improvement of 49 percent or greater in effluent concentrations of dissolved phosphorus, nitrate, orthophosphorus, and total suspended solids. On average, event mean concentrations of total phosphorus were reduced from a median 279 μg/l at the inflow to 94 μg/l at the outflow. Event mean concentrations of total nitrogen were reduced from a median 1,599 μg/l at the inflow to 810 μg/l at the outflow. Net nutrient retention for the sampling period was estimated at 3 g phosphorus (P)/m2/y and 13 g nitrogen (N)/m2/y. Almost 4,000 kg of suspended sediment was captured by this wetland system during the year. 相似文献
113.
The objective of this research was to analyze the retention of acid precipitation as a viable policy issue on the Congressional
agenda during the 1980s. Issue maintenance (a term borrowed from Barbara Nelson's discussion of the four stages associated
with agenda decision making) was examined in relation to a set of issue characteristics originally developed by Roger Cobb
and Charles Elder, i.e., concreteness, social significance, temporal relevance, complexity, and categorical precedence. Each
issue attribute was found to be somewhat useful in explaining the longevity of acid rain as an agenda item although the direction
of influence for two factors, complexity and temporal relevance, was contrary to expectations. It was suggested that a conceptual
merger of this sort could contribute to the comparative analysis of agenda policy decisions by providing a clearer and more
restricted set of decision points to be explained. 相似文献
114.
115.
Charles W. Howe 《Journal of the American Water Resources Association》1971,7(4):670-675
ABSTRACT
Three main issues are discussed: the demands for additional water stemming from population dispersion; supply alternatives to large-scale interbasin transfers; and the displacement of agriculture from nonprofit regions. It is concluded that population dispersion is unlikely to increase aggregate water demands; that large additional supplies are available from other sources at lesser costs; and that a very likely consequence of large-scale transfers will be the displacement of agriculture in other parts of the country. 相似文献
Three main issues are discussed: the demands for additional water stemming from population dispersion; supply alternatives to large-scale interbasin transfers; and the displacement of agriculture from nonprofit regions. It is concluded that population dispersion is unlikely to increase aggregate water demands; that large additional supplies are available from other sources at lesser costs; and that a very likely consequence of large-scale transfers will be the displacement of agriculture in other parts of the country. 相似文献
116.
ABSTRACT. The non-power requirements of a large hydro-power system of multiple-purpose projects often conflict with the best power peaking operation. In order to schedule an optimum multiple-purpose operation, advanced procedures that necessitate the use of computers are required. Special techniques are used in a computer program developed in the Reservoir Control Center, North Pacific Division of the Corps of Engineers that provide the ability to define operating constraints in order of priority. These techniques are easily adapted to practical reservoir regulation problems so that the program is useful in daily reservoir regulation scheduling. 相似文献
117.
118.
Automobile insurance claims were examined to determine the rates of neck injuries in rear-end crashes for vehicles with and without redesigned head restraints, redesigned seats, or both. Results indicate that the improved geometric fit of head restraints observed in many newer vehicle models are reducing the risk of whiplash injury substantially among female drivers (about 37% in the Ford Taurus and Mercury Sable), but have very little effect among male drivers. New seat designs, such as active head restraints that move upward and closer to drivers' heads during a rear impact, give added benefit, producing about a 43% reduction in whiplash injury claims (55% reduction among female drivers). Estimated effects of Volvo's Whiplash Injury Prevention System and Toyota's Whiplash Injury Lessening design were based on smaller samples and were not statistically significant. 相似文献
119.
Farmer CM 《Traffic injury prevention》2003,4(1):38-44
Posted speed limit and police-reported injury codes are commonly used by researchers to approximate vehicle impact and occupant injury severity. In-depth crash investigations, however, produce more precise measures of crash and injury severity: change in velocity (delta-V) for crash severity and Abbreviated Injury Scale (AIS) scores for injury severity. A comparison of data from police crash reports with that gathered by National Automotive Sampling System (NASS) investigators highlighted the inadequacy of speed limit and police injury codes as proxies for delta-V and AIS injury severity. In general, delta-V increased with speed limit and higher values of AIS were associated with higher police-coded injury severity, but there were a number of anomalies. In particular, 49% of the drivers coded by police as having incapacitating injuries actually had sustained no more than minor injuries. This overstatement of injury severity was less frequent among male (44%) and elderly (37%) drivers than among female (53%) and nonelderly (50%) drivers. Also, 79% of the investigated vehicles that crashed on roads posted at 60 mph (96 km/h) or higher experienced a delta-V less than 25 mph (40 km/h). Safety studies depending on data from only police reports to establish injury or crash severity therefore could produce erroneous results. 相似文献
120.
Blanchard CL Tanenbaum SJ 《Journal of the Air & Waste Management Association (1995)》2003,53(7):816-828
Ambient air quality data were analyzed to empirically evaluate the effects of reductions of volatile organic compounds (VOCs) and oxides of nitrogen (NOx) emissions on weekday and weekend levels of ozone (O3; 1991-1998) and particulate NO3- (1980-1999) in southern California. Despite significantly lower O3 precursor levels on weekends, 20 of 28 South Coast Air Basin (SoCAB) sites (28 of all 78 southern California sites) showed statistically significant higher mean O3 levels on Sundays than on weekdays (p < 0.01); 49 of the remaining 50 sites showed no significant differences between mean weekday and Sunday peak O3 levels. We also observed no statistically significant differences between mean weekday and weekend concentrations of particulate NO3- or nitric acid (HNO3, the precursor of particulate NO3-). Averaged over sites, the mean Sunday NOx and nonmethane hydrocarbon concentrations were 25-41% and 16-30% lower, respectively, than on weekdays. Site-to-site differences between weekend and weekday mean peak hourly O3 levels were related to whether O3 formation was limited by the availability of NOx. A thermodynamic equilibrium model predicts that particulate NO3- levels would decrease in response to a reduction of HNO3, and that particulate ammonium NO3- formation was not limited by the availability of ammonia. The similarity of mean weekday and weekend levels of NO3- therefore did not result from limitations on the formation of particulate NO3- from its precursor, HNO3. 相似文献