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ABSTRACT: The economic feasibility of a large scale dual purpose (desalting water and power production) facility were evaluated. Although a site in the Tularosa basin of southern New Mexico was chosen as a case study for this analysis, it is believed that the approach and consequential results would be applicable to alternative sites in the Southwest. The basic project evaluated included: a) a ground water well field; b) a dual purpose, nuclear, desalination plant; c) a mineral recovery plant; and d) a reservoir for recreation and irrigation storage. Principle project outputs included electrical power, minerals, recreation, and water for either irrigated agricultural production or export to an adjoining river basin. Two alternative project designs were developed for detailed analysis. The first alternative encompassed all major project components. The results, in discounted net values used to assess the feasibility of the project, were essentially negative; that is, values were less than zero for full scale development. The net benefits ranged from $-986.57 million at a 5 percent discount rate, to $-1,137.528 million at a discount rate of 10 percent. In the second alternative, exportation of the desalted water from the Tularosa basin to two adjacent rivers was analyzed with somewhat better net benefits, ranging from $-382,527 million to $-478,612 million at the 5 and 10 percent discount rates.  相似文献   
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Legislation in the United States has recently focused on improving water quality by establishing management practices that limit the quantities of nutrients entering the water supply. Timely application and quantification of the amount of manure applied throughout the grass-growing season can reduce the loss of nutrients into ground or surface water while improving the quality and quantity of grass harvested. During the 2001 and 2002 growing seasons, we measured the effects of different manure application rates on grass yields, grass nutritive value, and soil chemistry on a dairy farm. On-farm estimates of manure N were combined with yield estimates and forage quality measures to evaluate the effects of varying levels of manure application. Yield estimates, N content of grass, and the amount of N in soil and manure were monitored at each cutting for plots amended at different manure application rates. There are three major outcomes of this evaluation: (i) new grass seedings were at higher risk of elevated levels of nitrate N in forage; (ii) increased forage nitrate N at harvest was associated with malfermented silage and increased levels of ammonia N, which resulted in less efficient use of metabolizable protein for milk production; and (iii) increased understanding of N cycling between manure, soil, and plant provided an opportunity to reduce purchased fertilizer.  相似文献   
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