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91.
In Hawaii, trace concentrations of pesticides used in the production of pineapple were found in the groundwater supplies of
Mililani Town in the Pearl Harbor Basin on the island of Oahu. Groundwater serves as the major source of drinking water and
residents pay for wellhead treatment of the contaminated water, via their monthly water bill. The agricultural chemical users
within the Pearl Harbor Basin do not include these wellhead treatment costs in their production costs. The agricultural industry
benefits from using pesticides but does not pay the entire societal cost of using these chemicals. In this study we evaluate
the specific financial cost of wellhead treatment, and not the economic value of groundwater. While wellhead treatment costs
could conceivably be shared by several parties, this study focuses on the financial impact of the pineapple industry alone.
This study factors annual wellhead treatment costs into annual pineapple production costs to measure the effect on annual
financial return from pineapple production. Wellhead treatment costs are calculated from the existing granulated activated
carbon (GAC) water treatment facility for Millilani Wells I and II. Pineapple production costs are estimated from previous
cost of production studies. The inclusion of wellhead treatment costs produces different production-cost results, depending
on the scale of analysis. At the local scale, the Mililani wellhead treatment costs can be factored into the production costs
of the pineapple fields, which were probably responsible for contamination of the Mililani Wells, without causing a deficit
in economic return. At the larger regional scale, however, the return from all of the pineapple grown in the Pearl Harbor
Basin can not sustain the cost of wellhead treatmentfor the entire water supply of the basin. Recommendations point to the
prevention of groundwater contamination as more cost-effective measure than wellhead treatment. 相似文献
92.
Robert C. Borden Philip B. Bedient 《Journal of the American Water Resources Association》1987,23(4):629-636
ABSTRACT: A three well injection-production test was performed at the United Creosoting Company (UCC) site in Conroe, Texas, to estimate the effective in situ retardation factors for adsorption and to evaluate the significance of biotransformation in limiting the transport of polycydic aromatics present in the shallow aquifer. The field test was also used as a model to determine if this type of testing would be feasible at other hazardous waste sites. During the test, chloride, a non-reactive tracer and two organic compounds, naphthalene and paradichlorobenzene (pDCB), were injected into a center well for 24 hours followed by clean ground water for six days. Ground water was continuously produced from two adjoining wells and monitored to observe the breakthrough of these compounds. Data from the test were analyzed by comparing the statistical moments of the chloride and organics distributions. Retardation factors for naphthalene and pDCB were estimated to be 1.03 and 0.97 by comparison of the statistical moments. A significant loss of naphthalene and pDCB was also observed during the three well test, apparently due to biotransformation. These results suggest that biotransformation is the major process limiting the transport of naphthalene and similar compounds at the UCC site. 相似文献
93.
G. William Page 《Journal of the American Water Resources Association》1988,24(4):847-854
ABSTRACT: Contamination of ground water supplies with volatile organic compounds is a new and significant problem. Municipalities and their community water systems are often the first to discover ground water contamination because of the monitoring programs they are required to carry out. When contamination exceeds standards, some action is required. The responses of Wisconsin municipalities to volatile organic compounds that exceed standards in their ground water sources is described. Actions to protect human health are prompt, but the survey results indicate plumes of contaminated ground water are usually not treated. They may continue to migrate and contaminate other private and public wells. 相似文献
94.
五氯酚对环境污染及居民健康影响研究 总被引:2,自引:0,他引:2
中国长期以来使用五氯酚纳盐杀灭亡血吸虫的中间宿主──—钉螺.为评价它对环境的污染及居民健康危害,1990-1993年在我省开展了五氯酚环境污染及对居民健康影响研究.在研究区采集环境样品(空气、水体、土壤及底泥、蔬菜、肉、蛋、鱼等)共173份;生物材料(人血、尿)共457份,分析五氯酚浓度.结果在明,在五氯酚使用区,环境中PCP浓度稍高于对照区,而生物材料尿、血中PCP浓度明显高于对照区.全血胆碱脂酶活性用药区明显低于对照区,统计学分析有显著差异(P<0.001),证实了长期低剂量使用可造成环境及生物蓄积. 相似文献
95.
96.
本文对大巴山区农业生产中用化学药剂防治状况及存在的主要问题进行了分析研究。在此基础上,提出开展农药区划和区域性宏观调控,建立农药污染监测管理机制,进一步提高综合防治技术水平和专业化防治程度,加强防止污染微观技术的研究与推广控制策略和措施,以实现对化学药剂防治与农业生态环境保护。把农业环境保护工作纳入农业发展和国家农业环境保护的总体规划。 相似文献
97.
双流区域地下水污染现状及评价 总被引:1,自引:0,他引:1
本文在双流区域地下水污染调查基础之上,选用了主要反映工业生活污染的综合指标COD、BOD5和反映农业污染程度的NH3-N,NO3-N,NO2-N作为评价因子,研究了双流地下水污染现状,采用了综合指数法和点群分析法分类并评价了区域地下水污染对饮用水源地的影响程度。 相似文献
98.
Stanley N. Davis 《Journal of the American Water Resources Association》1973,9(5):1028-1034
ABSTRACT: Teodoro Ardemans, first post-Renaissance water expert of Spain, recognized problems of ground-water contamination, influence of minerals on water quality, and mutual interference between closely spaced wells. He is also noted for his achievements in architecture and the writing of the first comprehensive building code for Madrid. 相似文献
99.
Muniz P Danulat E Yannicelli B García-Alonso J Medina G Bícego MC 《Environment international》2004,29(8):1019-1028
As part of the first environmental assessment within Montevideo Harbour, in summer and winter of 1998, sediments samples were collected at eight locations to determine the spatial distribution of anthropogenic pollutants. Muddy sediments with high organic matter content dominate the study area. Heavy metal levels indicated that sediments were highly polluted with Zn (overall mean: 312+/-102 microg g(-1) dry sediment), Pb (85+/-31), Cu (89+/-25), Cr (162+/-62), and Hg (0.63+/-0.3) and moderately with Ni (30+/-2) and Ag (1.2+/-0.4). Depending on location and season, aliphatic hydrocarbons reached from 21 to 120 microg g(-1), while the unresolved complex mixture represented up to 76% of the total aliphatic fraction. Total PAH concentrations ranged from 1.56 to 90.44 microg g(-1); except at one location, petroleum derivatives were identified as main local source. The results pointed out that almost all the harbour area presented some substances that can cause adverse biological effects, especially in the inner region where all metals are above PEL levels. Principal components analysis confirmed that the inner harbour region is most severely affected by the pollutants and it was possible to differentiate three regions according to their environmental quality. 相似文献
100.
Environmental changes in Sepetiba Bay,SE Brazil 总被引:2,自引:0,他引:2
M.?M.?Molisani R.?V.?Marins W.?Machado H.?H.?M.?Paraquetti E.?D.?Bidone L.?D.?LacerdaEmail author 《Regional Environmental Change》2004,4(1):17-27
Sepetiba Bay is an example of an aquatic environment that has been severely impacted by human occupation and industrial activities in its basin. Some 400 industries including metallurgical, petrochemical and pyrometallurgical smelters, which emitted pollutants to air, soil and water, were established in Sepetiba Basin during the past 30 years. Apart from these point sources, changes in land use have also resulted in a large remobilization of pollutant deposition on Sepetiba Bay Basin. Studies have pointed out significant changes in sedimentation rates, concentrations of inorganic pollutants (Zn, Cd, Pb and Hg) and more recently, eutrophication, pointing to this area as an example of an impacted coastal zone. Notwithstanding local sources, Sepetiba Bay also suffers environmental impacts caused by diversion of river waters from adjacent basins, with some 30% of the total Hg flux to Sepetiba Bay and a 10-fold increase in water and sediment fluxes resulting from this. Decreasing environmental quality compromises both the large biodiversity and the potential economic uses of Sepetiba Bay, including fisheries and tourism. Monitoring of heavy metal levels in organisms (algae, mollusks, crustaceans and oysters) often shows concentrations well above the limits allowed following Brazilian legislation for food quality. Historical evolution of these concentrations suggests a worsening of the situation. Failure to monitor the effect of land-based activities, including those from other basins artificially associated with Sepetiba Bay has resulted in poor scenario construction and proper management planning. 相似文献