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191.
Jessica Sargent‐Michaud Kevin J. Boyle Andrew E. Smith 《Journal of the American Water Resources Association》2006,42(5):1237-1245
ABSTRACT: This study was undertaken to investigate the cost effectiveness of selected arsenic avoidance methods. Annual costs of reverse osmosis (RO), activated alumina (AA), bottled water, and rented and purchased water coolers for various household sizes in Maine were compared. Relative ranking of systems shows that RO ($411 annually) is the most cost effective, followed by AA ($518) and one‐gallon jugs of water ($321 to $1,285), respectively, for households larger than one person. One‐gallon jugs ($321) followed by 2.5‐gallon jugs ($358) of water were found to be the most cost effective for households of one person or for households with arsenic III concentrations of 0.02 to 0.06 mg/L and arsenic V concentrations of 0.08 to 1.0 mg/L. Point‐of‐entry systems and water coolers were not found to be cost effective under any of the study's conditions. The research reported here will help states make more definitive treatment recommendations to households regarding the cost effectiveness of alternative treatment systems to reduce arsenic concentrations below 0.01 mg/L. While arsenic removal technologies are improving, which enhances removal rates and reduces costs, the major insights from this analysis appear to be reinforced by technological improvements. 相似文献
192.
Donald M. Anderson Mark W. Rodney 《Journal of the American Water Resources Association》2006,42(5):1391-1403
ABSTRACT: Efforts are under way to recover habitat for several threatened and endangered species in and along the Platte River in central Nebraska. A proposed recovery program for these species requires a means of characterizing “wet” versus “normal” versus “dry” hydrologic conditions in order to set corresponding Platte River instream flow targets. Methods of characterizing hydrologic conditions in real time were investigated for this purpose. Initially, 10 watershed variables were identified as potentially valuable indicators of hydrologic conditions. Ultimately, six multiple linear regression equations were developed for six periods of the year using a subset of these variables expressed as frequencies of nonexceedence. The adequacy of these equations for characterizing conditions was assessed by evaluating their historic correlation to subsequent flow in the central Platte River (1947–1994). These equations explained 54 to 82 percent of variability in the observed flow exceedences in the validation datasets, depending upon the period of year evaluated. These equations will provide initial criteria for setting applicable flow targets to determine, in real time, whether water regulation projects associated with the species recovery effort can divert or store flows without conflicting with recovery objectives. 相似文献
193.
A national Baumol–Oates tax on waste in Denmark helped achieve a reduction of 26% in net solid waste from 1987 to 1998. The
tax, which is levied per ton of waste, was particularly effective as regards the heavier waste streams such as construction
waste and garden waste. When it comes to industrial and commercial waste, there are indications that the waste tax is not
sufficiently significant to induce changes in behavior, and that except for very waste-intensive enterprises, companies do
not seem to be very price sensitive. For household waste, the impact of the tax can be improved where tariffs for garbage
collection are weight based, rather than per unit. However, the waste sector is an area in which the price signals are modified
and filtered by institutionalized practices in municipal administration, and in which true-cost pricing is not easy to achieve.
Hence, the rational choice assumption of environmental economics needs to be supplemented by an institutional dimension to
interpret responses to environmental taxes correctly.
Received: July 13, 2001 / Accepted: October 2, 2001 相似文献
194.
本文回顾了我国环境保护产业的形成、发展及其特点。并从法律、经济、社会文化等方面分析了我国环保产业目前所处战略态势,就目前存在的问题和解决问题的方法做了分析探讨。 相似文献
195.
排污收费政策失灵分析 总被引:1,自引:0,他引:1
李克国 《中国环境管理干部学院学报》2002,12(1):8-11
在市场经济体制下,经常会出现政策失灵。本文首先介绍了政策失灵的基本理论,然后对我国的排污收费政策失灵进行了深入分析,最后提出了完善我国排污收费政策的对策。 相似文献
196.
K. K. Chatterjee 《Resources Policy》2002,28(3-4)
In India, the mineral resource inventory and the production of a large number of important minerals have registered significant increases during the last few decades. Yet the country continues to be a net importer of many high value and scarce minerals and metals, like gold, diamond, and several base metals. Exploration and development of the resources of these minerals are technology- and capital-intensive. To bring technology and capital through foreign direct investment (FDI) into the Indian mineral sector, it is imperative to lay stress on: accurate resource estimation and categorization, as well as realistic projection of the true values; rationalization of legislative measures based on R&D studies and reorganization of the implementation machinery; conducive tax structure; notification of acts and rules applicable to offshore mineral resources; time-frames for granting licences and leases; encouragement to labor productivity by rationalizing labor laws; reforms in the monetary system to increase market competitiveness of Indian minerals; and judicial reforms. FDI in the Indian mineral sector is important to firm up the knowledge-base of mineral resources and their optimum exploitation. 相似文献
197.
Harold L. Stone 《Journal of the American Water Resources Association》2002,38(4):1019-1026
ABSTRACT: This study was designed to give insight into the values considered in environmental policy and illustrate the respondents' personal constructions related to creating policy through the development of a graphic tool. Using both qualitative and quantitative methods, this study anonymously captured the intensity of values currently held by decision makers and tracked changes in values over time. Data were acquired through observations of and interviews with stakeholders in a five‐year wetland mitigation bank permitting process at the Galveston District of the U.S. Army Corps of Engineers. The study included public and private sector respondents in both governmental and nongovernmental roles. The resulting representations of professional and personal stakeholders' values can be used as a tool for improving information exchange in policy negotiation and provides insight into the complexity of individual and corporate perceptions of a policy issue. 相似文献
198.
199.
F. Andrew. Schoolmaster 《Journal of the American Water Resources Association》1992,28(3):495-505
ABSTRACT: Texans participate directly in water policy decision-making through a referendum process involving amendment of the state's constitution. Prior to 1985, Texans voted on eight amendments. Five of these were ratified (1957, 1962, 1966, 1971, 1976), and collectively resulted in the creation of the Water Development Fund, with an authorization level of $600 million, and the Texas Water Development Board, the organization charged with administering the fund. Three other amendments were defeated in 1969, 1976, and 1981 by ever-increasing margins. From 1985 to 1991, six additional amendments were proposed and subsequently ratified, resulting in a $1.8 billion increase in Water Development Fund authorization and the creation of an agricultural water conservation fund and bond insurance program. County-level electoral data for the 1985–1991 referenda were mapped to assess sectional and regional factors underlying public opinion regarding these water resource development and funding programs. Regional contrasts were most pronounced for the 1989 and 1991 referenda that targeted economically distressed areas across the state, particularly the colonias located along the Rio Grande, and the 1989 amendment that removed a time limit on the issuance of agricultural water conservation bonds. As a specific case study, the Texas experience could serve as a guide in California where similar constitutional restrictions require tax and spending programs to be approved by voters, and in other states that may be considering the development of similar state-level financial programs for water projects. 相似文献
200.
The article describes the historical development of water tariff policy in Tanzania from the colonial times to present. After
gaining independence, the country introduced “free” water policy in its rural areas. Criticism against this policy was expressed
already in the 1970s, but it was not until the late 1980s that change became unavoidable. All the while urban water tariffs
continued to decline in real terms. In rural and periurban areas of Tanzania consumers often have to pay substantial amounts
of money for water to resellers and vendors since the public utilities are unable to provide operative service. Besides, only
a part of the water bills are actually collected. Now that the free water supply policy has been officially abandoned, the
development of water tariffs and the institutions in general are a great challenge for the country. 相似文献