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21.
Prasanta Kumar Dey 《Environmental Impact Assessment Review》2002,22(6):509
The cross-country petroleum pipelines are environmentally sensitive because they traverse through varied terrain covering crop fields, forests, rivers, populated areas, desert, hills and offshore. Any malfunction of these pipelines may cause devastating effect on the environment. Hence, the pipeline operators plan and design pipelines projects with sufficient consideration of environment and social aspects along with the technological alternatives. Traditionally, in project appraisal, optimum technical alternative is selected using financial analysis. Impact assessments (IA) are then carried out to justify the selection and subsequent statutory approval. However, the IAs often suggest alternative sites and/or alternate technology and implementation methodology, resulting in revision of entire technical and financial analysis. This study addresses the above issues by developing an integrated framework for project feasibility analysis with the application of analytic hierarchy process (AHP), a multiple attribute decision-making technique. The model considers technical analysis (TA), socioeconomic IA (SEIA) and environmental IA (EIA) in an integrated framework to select the best project from a few alternative feasible projects. Subsequent financial analysis then justifies the selection. The entire methodology has been explained here through a case application on cross-country petroleum pipeline project in India. 相似文献
22.
John Troiano Craig Nordmark Terrell Barry Bruce Johnson 《Environmental monitoring and assessment》1997,45(3):301-319
A well sampling study was conducted to evaluate anempirical approach to classifying areasof land in California as vulnerable to ground watercontamination by pesticides (Troiano et al., 1994). Wells were sampled from sections of land that had noprevious detections of pesticideresidues. The sections had been classified into vulnerablesoil clusters or into a not-classified groupusing a procedure based on Principal Components Analysis(PCA). Grape, citrus, and olive growingareas of Fresno and Tulare Counties were targeted, areas wherepre-emergence herbicide residues hadbeen detected in well water. Overall, herbicide residues weredetected in 75 of 176 sampled wells, ahigh frequency of detection in relation to results fromprevious targeted well sampling studies. Sinceresidues were also detected in the not-classified group, theclassification procedure was modified usingan approach based on Canonical Variates Analysis (CVA). Moresections were classified intovulnerable soil clusters with the CVA approach than with thePCA method. Data from two otherexplanatory variables, depth to ground water and amount ofpesticide used per section, were includedto illustrate how additional information can be incorporatedinto this approach of identifying vulnerable areas. 相似文献
23.
Diazinon contamination of California's rivers has resulted in placing several rivers on the federal Clean Water Act § 303d list of impaired waterways. Impaired water body listing requiresthe development of Total Maximum Daily Loads (TMDL). Previous studies identified stormwater related diazinon pulses in California rivers. This study was conducted to monitor diazinonconcentrations in the Sacramento River watershed after rainfallevents, to ascertain whether pulses could be identified and, ifconcentrations of concern were observed, to estimate loadings anddetermine geographic origins of the insecticide. TMDL developmentrequires knowledge of contaminant sources, loadings, and geographic origins. Flow and diazinon concentrations peaked in the Sacramento River at Sacramento after the three largest stormsduring January and February 1994. Diazinon concentrations peakedconsequent to each of three storms. Diazinon concentrationsmeasured in the Sacramento River at Sacramento exceeded theCalifornia Department of Fish and Game acute and chroniccriteria for protection of aquatic life during January andFebruary for nine and nineteen days, respectively. Multipleexceedances were observed throughout the watershed. Diazinon loading and geographic origin differed with each of the three storms. The design of this study provides a useful template for others attempting to identify loadings and sources of contaminants in surface waters and to rectify aquatic ecosystemcontamination from various land use practices. 相似文献
24.
利用一个三维非静力区域大气化学输送模式与中尺度气象模式MM5相连接构成一个数值模拟系统,模拟了中国地区对流层臭氧与其前体物的分布以及二氧化硫转化为硫酸盐的过程,模式扬地面源排放、大气输送和扩散、干沉积、气相化学反应和云雨过程。结果表明:日间,O3浓度主要由NOx和NMHC的源排放和光化学反应过程支配,大气辐射是光化学反应强弱的决定因子,其强度可使SO2、O3和SO4^2-的生成浓度呈现不同的日变化和季节变化,结果表明高浓度的O3对二氧化硫转化为硫酸盐的化学过程有很大的促进作用,然而,这种作用受NMHC浓度的影响很大,较高浓度的NMHC使O3浓度上升,但同时增加了对OH等自由基的消耗,使SO2的转化率降低。 相似文献
25.
我国城市降雨径流污染控制模式探讨 总被引:1,自引:0,他引:1
随着城市的发展与点源污染控制的不断完善,城市降雨径流污染日益突出,对城市水体构成严重威胁,必须得到有效的控制。对国内外城市降雨径流污染控制模式进行了比较,并结合我国的实际情况,首次提出了双重控制模式,以期为我国城市降雨径流污染的控制与决策提供参考和借鉴。 相似文献
26.
对含柠檬酸盐电镀废水的几种处理方法的比较表明,氯化钡添加法能较好地使柠檬酸盐沉淀,操作简便,处理效果理想,其柠檬酸根离子的去除率达98%以上。 相似文献
27.
28.
硫酸法钛白生产水洗工序清洁生产技术初探 总被引:1,自引:0,他引:1
通过开展水洗工段用水审计并试验了温度、偏钛酸ξ电位和漂白工艺对水洗的影响效果,从实践和理论上探讨了为其提高钛白质量改进水洗工艺的清洁生产方案的可行性和合理性。 相似文献
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30.
田博 《辽宁城乡环境科技》2007,27(1):19-21
介绍了将铁法煤业(集团)有限责任公司三台子矿区污水处理工程工艺由以卡鲁塞尔氧化沟为主体的二级生化处理工艺改造为更适宜在北方气候条件下运行的A-O法工艺;同时对系统的启动进行了介绍。 相似文献