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981.
982.
William Whipple 《Journal of the American Water Resources Association》1991,27(6):895-902
ABSTRACT: Water quality controls of storm water runoff and infiltration should be a major part of a nonpoint source control program. Although surface runoff and ground water controls are often approached separately, coordination between the two is essential. For practical reasons, a rather simplified technology-based approach appears to be desirable. Areas affected vary greatly as to their sensitivity to pollution; and the various classes of pollutant source vary greatly as to their potential harmfulness. In effect, a matrix approach appears best, in which both vulnerability of the area and harmfulness of the pollutant source would have weight in determining which level of best management practices (BMP) would be appropriate, whether standard, special, or complete prohibition of the type facility under given circumstances. 相似文献
983.
William D. Watson Ronald G. Ridker 《Journal of Environmental Economics and Management》1984,11(4):310-326
Recent theoretical papers by Adar and Griffin (J. Environ. Econ. Manag.3, 178–188 (1976)), Fishelson (J. Environ. Econ. Manag.3, 189–197 (1976)), and Weitzman (Rev. Econ. Studies41, 477–491 (1974)) show that,different expected social losses arise from using effluent taxes and quotas as alternative control instruments when marginal control costs are uncertain. Key assumptions in these analyses are linear marginal cost and benefit functions and an additive error for the marginal cost function (to reflect uncertainty). In this paper, empirically derived nonlinear functions and more realistic multiplicative error terms are used to estimate expected control and damage costs and to identify (empirically) the mix of control instruments that minimizes expected losses. 相似文献
984.
985.
986.
John Van Benschoten William W. Walker Jr. 《Journal of the American Water Resources Association》1984,20(1):109-117
ABSTRACT: A modified version of the U.S. Environmental Protection Agency's QUAL-II water quality simulation model is calibrated and applied to the Lower Winooski River, Vermont. The river flows through the metropolitan Burlington area and is impacted by several industrial and municipal point sources and by operation of hydropower facilities. Several structural modifications are made in the model to improve water quality simulations in rivers impacted by algal growth; these include the addition of organic nitrogen and organic phosphorus compartments and provision for algal uptake of ammonia and/or nitrate nitrogen. The model is interfaced with statistical programs which facilitate tabulation, display, and analysis of observed and predicted concentrations. The model is calibrated and tested against data from two intensive water quality surveys. Applications demonstrate the factors controlling water quality and sensitivities to point source waste management strategies and flow, as influenced by hydropower operations. 相似文献
987.
Biological processes have been used to remediate petroleum hydrocarbons, pesticides, chlorinated solvents, and halogenated aromatic hydrocarbons. Biological treatment of contaminated soils may involve solid-phase, slurry-phase, or in situ treatment techniques. This article will review the general principle of solid-phase bioremediation and discuss the application of this technique for the cleanup of total petroleum hydrocarbons on two sites. These remedial programs will reduce total petroleum hydrocarbon contamination from the mean concentration of 2,660 ppm to under the 200-ppm cleanup criteria for soil and under the 15-ppm cleanup criteria for groundwater. Over 32,000 yards of soil have been treated by solid-phase treatment to date. The in situ system operation is effectively producing biodegradation in the subsurface. The project is approximately one-third complete. 相似文献
988.
989.
Policy windows are transitory opportunities during which the likelihood of adopting new policy or legislative proposals is
greater than usual. Accepted wisdom has held that natural disasters serve as focusing events that generate policy windows
in their wake. This paper highlights the need for a more circumscribed understanding of when and where policy windows occur
based on the experiences of three US regional planning organizations: a hand-picked commission of community leaders, a council
of governments, and a special-purpose substate organization. The first operated in the San Francisco Bay Area of California
following the Loma Prieta earthquake (October 1989), and the other two in South Carolina's Atlantic coastal plain after Hurricane
Hugo (September 1989). The analysis concludes that natural disasters did not transform the agenda or mission of these entities.
Policy windows were neither automatic outcomes of focusing events nor did they ensure the adoption of pertinent policy within
the organizations investigated. Several conditions are minimally necessary for using policy windows to bring about hazard
mitigation: comprehensive institutional conceptualization of hazards management, institutional strength and flexibility, and
well-placed, effective policy entrepreneurs. 相似文献
990.