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81.
82.
Edwin D. Bailey 《Journal of the American Water Resources Association》1979,15(3):801-811
ABSTRACT: The Tucson area is totally dependent on ground water, which is in increasingly short supply due to excessive overdrafts. Tucson area waste water treatment plants discharge material quantities of secondary effluent downstream, which is lost to evapotranspiration and recharge of the ground water basin. The city and the four large mining companies who share the common Santa Cruz basin ground water, recognized the common water supply problem and agreed to fund a feasibility study for mining process use of the effluent to partly alleviate the overdraft of ground water. The study analyzed the projected waste water effluent resources, potential mining company demand for waste water effluent and possible interface of an effluent delivery facility with the proposed Central Arizona Project. The effluent resources were analyzed with respect to potential demand. An optimum alignment was selected. An optimum system was detailed through design schematics, amortized cost and finance requirements, and an implementation schedule. It was concluded that a waste water effluent delivery facility could be implemented which would utilize reclaimed effluent in quantities approximating 35 percent of basin overdraft and which would provide revenue for full cost recovery over a 20 year operation period. The mining companies are studying the internal economic impacts of the project. 相似文献
83.
James E. Fitting 《Environmental management》1977,1(5):419-423
Like many environmental sciences, archaeology has its origins in an academic discipline. But organizational models derived from scholarly research are not adequate for large scale archaeological salvage excavations that must be carried out by many archaeologists within a short time. A non-traditional organization model, developed to parallel the organization of project engineering, is more responsive and can be designed to preserve the most significant traditional archaeological objectives. 相似文献
84.
Declines in salmon stocks and general watershed health in Washington State, USA, have led to an increase in stream restoration
and enhancement projects initiated throughout the state. The increasing number of projects has also raised questions regarding
the monitoring of these efforts. Project managers receiving hydraulic project approvals (HPAs) were surveyed to determine
whether monitoring was taking place on their projects. About half the project managers surveyed reported the collection of
baseline data and the use of biological, physical, chemical, or other water quality measures for their projects. Of those
who reported collection of monitoring data, only 18% indicated that monitoring was required. Respondents were also asked to
rank the importance of various project goals on a Likert scale. Project managers with projects focusing on “engineering” goals
(e.g., roadbed stabilization) were less likely than other project managers to collect baseline monitoring data. Project managers
with projects focusing on “restoration/ecological” or “fisheries” goals were more likely than other project managers to collect
monitoring measures. Although monitoring appears to be taking place in slightly more than half of the projects surveyed, the
nature of the data collected varies widely across projects, and in most cases the monitoring effort is voluntary. This suggests
that project sponsors, funders, and managers must consider the issues involved in requiring appropriate monitoring, establishing
standardized monitoring guidelines, the time frames in which to monitor, providing other incentives for conducting monitoring,
and ensuring adequate funding for monitoring efforts. 相似文献
85.
实行最严格水资源管理制度是2011年中央一号文件明确要求的内容。在分析最严格水资源管理初始水权分配内涵的基础上,首次以水资源管理“三条红线”为准则,构建了包含目标层、准则层、指标层及方案层4个层次结构的初始水权分配指标体系,建立了最严格水资源管理初始水权分配的投影寻踪模型,并采用量子遗传算法优化投影指标函数,以模型计算出的最佳投影值作为初始水权分配的分水比例。最后,以南水北调东线一期工程为例,将本文所建立的模型用来分配该工程净增加供水量的初始调水量。结果表明:该指标体系和模型具有一定的可操作性及有效性。 相似文献
86.
87.
南水北调中线工程总干渠河南段原水中消毒副产物前体物变化规律 总被引:2,自引:0,他引:2
以取自南水北调中线总干渠河南段沿线10个分水口门的原水为研究对象,探究了原水中有机物的相对分子质量分布和亲疏水性分布规律;并且研究了原水在氯化和氯胺化条件下消毒副产物生成潜能的变化规律.分离实验结果表明,南水北调沿程原水中的有机物以小分子和强疏水性为主,1×103区间的溶解性有机碳(DOC)所占的比例最大,质量分数约为57%,强疏水性组分的DOC含量最高,占到总量的50%左右;氯化及氯胺化消毒副产物生成潜能分析实验结果表明,氯化及氯胺化后主要生成了两种含碳消毒副产物(三氯甲烷和一溴二氯甲烷)和两种含氮消毒副产物(二氯乙腈和三氯硝基甲烷).氯化三氯甲烷生成潜能约为120μg·L-1,与氯化生成潜能相比,氯胺化三氯甲烷生成潜能减少了90%左右,一溴二氯甲烷减少了84.9%左右,生成的两种含氮消毒副产物增加了,其中二氯乙腈的生成量增加了约2.3倍,但总含氮消毒副产物生成潜能仍旧较低,均小于6μg·L-1.本研究成果可为南水北调中线工程河南段沿线城市的水厂工艺选择和优化提供有效的理论和技术支持. 相似文献
88.
89.
投资体制改革后项目核准备案与环评审批衔接过程中存在诸多问题,拟从政策、法律、部门配合等层面提出对策和建议。 相似文献
90.
通过对南城子水库面源污染的调查和对监测结果的分析,预测了全流域面源污染入库量及对水库水质的污染程度,并提出了面源污染的控制方案。 相似文献