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61.
William Lin Robert L Spore Edmund A Nephew 《Journal of Environmental Economics and Management》1976,3(3):236-252
This study quantifies the short-run impacts of reclamation on strip mining costs, coal prices, production, and employment in Appalachia. A process analysis model is developed and used to estimate short-run strip-mined coal supply functions under conditions of alternative reclamation requirements. Then, an econometric model is developed and used to estimate coal demand relations. Our results show that full reclamation has rather minor impacts. In 1972, full reclamation would have increased strip-mined coal production costs an average of $0.35 per ton, reduced strip-mined coal production by 10 million tons, and cost approximately 1600 jobs in Appalachia. 相似文献
62.
Sadika M. Baladi Catherine M. Lewis Amitava Ganguly Alvin G. Morrow Lisel R. Shoffner Robert F. Blundy Patrick F. Nakagawa Sara T. Mundy Larry Anderson Karen Adams 《补救:环境净化治理成本、技术与工艺杂志》2003,14(1):5-20
Enhanced bioremediation is quickly developing into an economical and viable technology for the remediation of contaminated soils. Until recently, chlorinated organic compounds have proven difficult to bioremediate. Environmentally recalcitrant compounds, such as polychlorinated biphenyls (PCBs) and persistent organic pesticides (POPs) such as dichlorodiphenyl trichloroethane (DDT) have shown to be especially arduous to bioremediate. Recent advances in field‐scale bioremedial applications have indicated that biodegradation of these compounds may be possible. Engineers and scientists at the Savannah River Site (SRS), a major DOE installation near Aiken, South Carolina, are using enhanced bioremediation to remediate soils contaminated with pesticides (DDT and its metabolites, heptachlor epoxide, dieldrin, and endrin) and PCBs. This article reviews the ongoing remediation occurring at the Chemicals, Metals, and Pesticides (CMP) Pits using windrow turners to facilitate microbial degradation of certain pesticides and PCBs. © 2003 Wiley Periodicals, Inc. 相似文献
63.
In situ chemical fixation represents a promising and potentially cost‐effective treatment alternative for metal‐contaminated soils. This article presents the findings of the use of iron‐bearing soil amendments to reduce the leachability and bioaccessibility of arsenic in soils impacted by stack fallout from a zinc smelter. The focus of this investigation was to reduce the lead bioaccessibility of the soils through addition with phosphorus‐bearing amendments. However, as phosphorus addition was expected to increase arsenic mobility, the fixation strategy also incorporated use of iron‐bearing amendments to offset or reverse these effects. The findings of this investigation demonstrated that inclusion of iron‐bearing chemicals in the amendment formulation reduced arsenic leachability and bioaccessibility without compromising amendment effectiveness for reducing lead bioaccessibility. These results suggest that in situ chemical fixation has the potential to be an effective strategy for treatment of the impacted soils. © 2003 Wiley Periodicals, Inc. 相似文献
64.
This paper investigates the European Commission's decision to allow a merger between two Brazilian iron ore mining companies, CVRD and Caemi, using data on the Direct Reduced Iron pellet market. By using a simulation model, we can directly simulate the total welfare effects from the merger and hence evaluate the merger from a new perspective. The results from our simulations suggest that the welfare effects are negative from the merger between CVRD and Caemi, which supports the conclusion drawn by the European Commission decision. By performing different simulations between hypothetical merger candidates, our results show that only mergers between small candidates have the potential to be welfare enhancing. 相似文献
65.
Keith E. Schilling Robert D. Libra 《Journal of the American Water Resources Association》2003,39(4):851-860
ABSTRACT: Historical trends in annual discharge characteristics were evaluated for 11 gauging stations located throughout Iowa. Discharge records from nine eight‐digit hydrologic unit code (HUC‐8) watersheds were examined for the period 1940 to 2000, whereas data for two larger river systems (Cedar and Des Moines Rivers) were examined for a longer period of record (1903 to 2000). In nearly all watersheds evaluated, annual base flow, annual minimum flow, and the annual base flow percentage significantly increased over time. Some rivers also exhibited increasing trends in total annual discharge, whereas only the Maquoketa River had significantly decreased annual maximum flows. Regression of stream discharge versus precipitation indicated that more precipitation is being routed into streams as base flow than as storm flow in the second half of the 20th Century. Reasons for the observed stream flow trends are hypothesized to include improved conservation practices, greater artificial drainage, increasing row crop production, and channel incision. Each of these reasons is consistent with the observed trends, and all are likely responsible to some degree in most watersheds. 相似文献
66.
67.
Robert Soden 《中国安全生产科学技术》2003,(6):36-37
由于国际市场的萎缩,公司的业务领域正日益全球化,公司应该按照国际标准,在世界范围内审查其行为表现。贸易呈现多样化及国际化,内部控制战略更需要健全。公司自成立之日起,一直致力于规避风险。风险是商业的有机组成部分,许多人也许认为风险越大,则回报越多。然而,从现代意义上来讲,需要确保组织对经济、社会或者环境的影响在公司的控制之下,从而确保为公司股东长期提供利益的增长。建立一个清晰、明了的风险战略对公司而言至关重要。许多公司已经采用了管理体系标准,并意识到这些标准将有助于利用已经构建的方法对优先权冲突进行管理。公… 相似文献
68.
Oliveira Amauri P. Bornstein Robert D. Soares Jacyra 《Water, Air, & Soil Pollution: Focus》2003,3(5-6):3-15
The major topographic, mesoscale, and urban influences on the wind patterns of the City of São Paulo are characterized using one year of surface wind velocity data observed at 11 surface stations within its urban limits. The data was used to study the diurnal and annual variations of wind velocity and horizontal wind divergence within the city. Results showed that the circulation over the investigated area is dominated by three major factors: sea breeze; mountain-valley circulations; and urban effects, such as roughness, building-barrier, and urban heat island. The sea breeze was found to be the dominant feature of the monthly-averaged diurnal variation of São Paulo surface winds during the eight warmest months of the year. The sea breeze front induces a velocity minimum at the time of its passage and a post-frontal afternoon velocity maximum. Mountain-valley thermal effects on the flow can be seen in the temporal divergence/convergence patterns. These thermal effects tend to be more important during colder months, at night, and when the wind velocities are low. Nighttime downslope convergent flows are present over the city during winter and spring and daytime upslope divergent flows are present over the city during summer months. 相似文献
69.
Jon Martin Trolldalen 《Natural resources forum》1997,21(2):101-108
Water disputes in the Middle East are not a new phenomenon. For the first time, however, three parties in the region, Jordan, Israel, and the PLO for the benefit of the Palestinian Authority have concluded a "regional water agreement" within the framework of the Multilateral Peace talks. For the first time, the rationale behind the agreement is being made public by the author, who was the "neutral" facilitator of the negotiations. The article discusses some of the main elements, including issues related to water scarcity as a driving force of conflicts; application of a "track-two diplomatic" approach; some lessons learned; as well as some ethical questions related to international negotiation. 相似文献
70.
John H. Martin 《Journal of the American Water Resources Association》1997,33(4):741-753
ABSTRACT: On May 19, 1993, a jury in the U.S. District Court for the Western District of New York found Southview Farm and Richard H. Popp guilty of violating the Clean Water Act on five occasions. The violations were the result of storm water runoff from a site used for disposal of dairy cattle manure from an unpermitted concentrated animal feeding operation. The presiding District Court judge later dismissed the jury verdict, and subsequently a U.S. Court of Appeals for the Second Circuit reversed the dismissal. The Court of Appeals concluded that the discharges were not exempt as agricultural storm water discharges, and that the manure spreaders involved were point sources. Because the use of animal manures in crop production activities will result, unavoidably, in the discharge of some pollutants to adjacent surface waters, a rational and universally applicable basis is needed to determine when such discharges are point versus nonpoint source. Current statutes and regulations do not delineate clearly such a boundary. To address this lack of specificity, I propose that application rates be based on recommended crop nutrient needs. 相似文献