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91.
The National Environmental Policy Act (NEPA) of 1969 and the Council on Environmental Quality (CEQ) regulations in the United States require federal agencies to apply an environmental impact assessment (EIA) in decision-making related to their actions. One aspect requires an examination of direct, indirect and cumulative impacts (CIs). Historically, cumulative impact assessment (CIA) has been given limited attention in EIA and resultant environmental impact statements (EISs), not because of its lack of importance, but owing to limitations in methodologies and procedures, including documentation consistency. The objectives of this study were to identify deficiencies in the documentation of CIs and CIA in EISs and to formulate appropriate recommendations (potential solutions) related to such deficiencies. The study involved the systematic review of 33 EISs (11 each from the U.S. Department of Agriculture: Forest Service, the U.S. Army Corps of Engineers, and the U.S. Department of Transportation: Federal Highway Administration). The results indicate that improvements have been made in documentation practices since 1990; however, inconsistencies and inadequacies still exist. Therefore, the following recommendations were developed: (1) CIs should be reported in a separate part of the “Environmental Consequences” section, and they should be addressed for each pertinent environmental resource; (2) a summary of CIs should be included; (3) any CIs considered not significant should be mentioned plus the reason(s) for their non-significance; (4) spatial and temporal boundaries addressed within the CIA process should be defined for pertinent environmental resources; and (5) utilized guidelines and methodologies should be described. 相似文献
92.
以邢台市环境保护监测站10年来的监测资料为依据,运用单因子比值法,环比发展速率外推法和直线回归法,对地下水环境质量现状及10年的动态变化进行了分析,研究和评述,并对发展趋势做了预测性评价。 相似文献
93.
对色泽较深,含杂质量较高的废水加硅油I以抑制测定中蒸馏产生的泡沫.结果表明,在250ml水样中加硅油IO.10~1.25ml,即可收到理想效果.硅油I性质稳定,不随水蒸汽蒸出,对测定无干扰. 相似文献
94.
于2015年10月对上海市嘉定区4家(A、B、C、D)汽车制造企业涂装废气ρ(VOCs)和组成特征进行了调查分析。结果表明,A、B、C、D厂涂装废气排放口ρ(VOCs)总为0. 743~6. 11 mg/m~3,主要检出物和最高检出值分别为:A厂二甲苯2. 06 mg/m~3、B厂二甲苯0. 578 mg/m~3、C厂甲苯2. 59 mg/m~3、D厂庚烷0. 274 mg/m~3;芳香烃类是A、B、C厂排放比例最高的VOCs组分,烷烃类是D厂排放比例最高的VOCs组分。指出,原、辅料种类影响排放物的主要成分,废气处理工艺类型影响排放物主要成分和浓度。 相似文献
95.
Young northern pike,yellow perch and crayfish as bioindicators in a mercury contaminated watercourse 总被引:2,自引:0,他引:2
J. W. Parks C. Curry D. Romani D. D. Russell 《Environmental monitoring and assessment》1991,16(1):39-73
Young-of-the-year and yearling northern pike (Esox lucius), yearling yellow perch (Perca flavescens) and adult crayfish (Orconectes virilis) were collected in the mercury-contaminated Wabigoon/English/Winnipeg River System, Ontario, and analyzed for total mercury. Analysis of mercury concentrations in these organisms produced consistent geographical trends; i.e. mercury concentrations in biota downstream of Dryden > English River system > Winnipeg River system > control sites. In the Wabigoon River system the bioavailability of mercury increases with distance downstream of the historical point source. Mercury concentrations in the biota studied were highly correlated with mercury concentrations in fish species which are of sport and commercial interest. The locations where young fish obtain their bodyburdens are known typically within 100 m. The biota studied compare favourably with the criteria proposed by Phillips (1980) as prerequisites for biological indicators. The wide distribution of young pike, perch and crayfish in North America, Europe and Asia may enhance their appeal as biomonitors.The views expressed are those of the authors and do not necessarily reflect the views of the Ontario Ministry of the Environment. No endorsement should be inferred. 相似文献
96.
The composition of precipitation is being monitored in collectors sited throughout the United Kingdom. In the first year, 1986, hydrogen ion, nitrate, ammonium and non-marine sulphate were measured in samples from 47 sites and annual mean concentrations determined. Spatial analysis based on Regionalized Variable Theory revealed autocorrelation in all four ions and reasonable bounded models were fitted to the sample variogram of all four. These were then used to estimate values of a fine mesh grid by simple kriging, and the estimates were then contoured. The estimation errors were similarly mapped, and both sets of maps are presented. The maps show that concentrations of these ions are greatest in eastern parts of the country, as expected from consideration of European emissions and weather patterns. For the first time estimation errors were also mapped and show how the network could be improved. 相似文献
97.
Excrement cast from Great Blue Heron nests was collected during the nesting period of 1978 from four colonies in Washington and Idaho. Cheesecloth strips placed on the ground beneath the nests served as excrement collecting devices. Chemical analysis for lead, mercury and cadmium were performed on dried samples. Lead was the most abundant trace metal found in heron debris. The Idaho colony at Lake Chatcolet had an average concentration of 46 ppm in the beneath-nest samples and 6 ppm in control samples. A heron colony near Tacoma, Washington had beneath-nest samples averaging 28 ppm and control samples averaging 20 ppm. Two colonies located in the interior region of Washington had substantially lower concentrations of lead. The difference observed between colonies was attributed to their associations with a polluted watershed (Chatcolet colony) an interstate highway (Tacoma colony) and an unpopulated largely agricultural area (inland Washington). 相似文献
98.
大气连续采样在乌鲁木齐应用分析 总被引:3,自引:0,他引:3
对乌鲁木齐市大气连续采样方法试运行实验进行总结,比较了以往的定时采样方法后认为,连续采样方法更准确反映本地大气污染物的状况。 相似文献
99.
Strontium-90 (90SR) released to the ground near the N Reactor at the U.S. Department of Energy's Hanford Site enters the Columbia River through shoreline seeps. The 90Sr is then potentially available for uptake by plants and animals. The life history and foraging behavior of nesting Canada geese is such that female geese could ingest 90Sr while foraging on shoreline plants. Radichemical analyses showed that goose eggshells taken from an island, downstream from the N Reactor, contained more 90Sr than did eggshells collected from other downstream islands. Reed canary grass samples taken from shoreline areas immediately downstream from the N Reactor contained higher concentrations of 90Sr than samples from other downstream areas. All goose eggshells did not contain enhanced levels of 90Sr, and all reed canary grass samples did not contain enhanced levels of 90Sr, but a relationship exists between the releases of 90Sr to the Columbia River and the enhanced levels of 90Sr in some of the environmental samples analyzed.Pacific Northwest Laboratory is operated by Battelle Memorial Institute for the U.S. Department of Energy under contract DE-ACO6-76RLO 1830. 相似文献
100.
ICP-MS analysis recorded historical change (c. 1846 to 2002) in the arsenic concentration of bark included within the trunks (tree bark pockets) of two Japanese oak trees (Quercus crispula), collected at an elevated location approximately 10 km from the Ashio copper mine and smelter, Japan. The arsenic concentration of the bark pockets was 0.016 +/- 0.003 microg cm(-2) c. 1846 (n = 5) and rose 50-fold from c. 1875 to c. 1925, from approximately 0.01 to 0.5 microg cm(-2). The rise coincided with increased copper production in Ashio from local sulfide ores, from 46 tons per year in 1877 to 16,500 tons per year in 1929. Following a decline in arsenic concentration and copper production, in particular during the Second World War, a second peak was observed c. 1970, corresponding to high levels of production from both local (6,000 tons per year) and imported (30,000 tons per year) ores, smelted from 1954. Compared to the local ores, the contribution of arsenic from imported ores appeared relatively low. Arsenic concentrations declined from c. 1970 to the present following the closure of the mine in 1974 and smelter in 1989, recording 0.058 +/- 0.040 microg cm(-2) arsenic (n = 5) in surface bark collected in 2002. The coincident trends in arsenic concentration and copper production indicated that the bark pockets provided an effective record of historical change in atmospheric arsenic deposition. 相似文献