The Bhopal tragedy: its influence on process and community safety as practiced in the United States

The chemical accident at 12:45 AM on December 3, 1984 in Bhopal India had a profound effect on the practice of chemical process safety in the United States. Fearing the possibility of similar events occurring in the United States, the United States Congress convened several hearings and investigations into the causes of the disaster. The inquiries focused both on the state of process safety within the US chemical industry and on the readiness of communities located near chemical operations to respond to sudden and dangerous toxic discharges. Of equal significance were concerns over the safety of workers in chemical plants. This paper reviews the major legislative, academic, and industrial changes initiated in the area of process safety after the event, their influence on saving lives, and on improving living conditions surrounding chemical complexes in the United States.     

美国环保署农药地下水风险评估模型

在介绍美国农药环境风险评估的概念、分级、地下水农药监测情况及水资源的立法保护等基础上,重点阐述了美国环保署在农药登记管理过程中使用的2个地下水风险评估模型,即SCI-GROW和PRZM-GW模型。SCI-GROW是以好氧条件土壤半衰期和土壤有机碳分配系数为自变量的经验线性回归模型,而PRZM-GW则是描述农药在土壤中运动的一维、有限差分模型。本文通过对美国环保署这2个特点鲜明的模型的介绍,希望能为我国的农药地下水风险评估及模型的开发提供一个新视角。     

The role of co-products in stabilizing the metal mining industry

The objective of this paper is to test the hypothesis that cyclical metal mining activity is more stable when multi-metal products are produced. A theoretical short-run supply curve for a metal is developed showing by-product, co-product, and main product behaviour. This curve is used to illustrate co-product pricing trends that are indicative of different cyclical behaviour patterns. The non-parametrical sign test is used to test co-product price trends for the US metal mining industry. The results indicate that multi-metal production stabilizes the mining industry in the short run but not in the long run.     

Regional resource management techniques: The case of Colorado oil shale development

Regions under stress from rapid development require comprehensive planning and management tools, capable of identifying the pace, location and magnitude of growth and assessing social, economic and environmental impacts. Northwest Colorado, endowed with massive rich deposits of oil shale, went through a boom-bust cycle of growth during the early 1980s as US interest in synthetic fuels peaked and then rapidly declined. An innovative resource information system has been developed which has assisted the region in anticipating growth and modifying its consequences. This article reviews the organization and development of the Colorado Resource Information System (CRIS) and evaluates its role and impact in the decisionmaking process. Experience shows that regions which develop and maintain planning and information tools can have significant influence on economic development.     

Use and abuse of Pb-isotope fingerprinting technique and GIS mapping data to assess lead in environmental studies

The danger to health, especially of young children, from lead-bearing particulates in the surface environment is still a valid concern. Given the multifaceted uses of lead today as well as historically, the sources of lead must be investigated to distinguish the etiology of lead contamination on the environment. The lead isotope finger printing technique based on isotopic ratio analyses (IRA) is one of the methods used commonly for provenancing lead sources in environmental studies throughout the world. This technique, however, has some inherited shortcomings. Therefore, caution must be used in the interpretation of the results, as this technique can lead to overestimations as well as underestimations of the true source etiology/apportionment of lead in specific environments. This paper illustrates this with some examples. Data on geographical information systems (GIS) mapping in urban regions are also presented in this paper.     

Forward pricing and efficiency in the silver market

If futures prices ‘fully reflect’ all available information, then these prices may be interpreted as market anticipations of spot (cash) prices at the delivery date of the futures contract. This hypothesis, which has tended to find most support among established markets for storable commodities, is investigated for the Chicago silver futures market. Using instrumental variable estimation and a joint (χ²) test, the unbiased prediction hypothesis is rejected, and a tentative explanation is offered for this outcome. This result, however, does not necessarily imply that the market is inefficient, and two tests of the weak form efficient markets hypothesis suggest that, while there is some slight dependence in past prices, this is only marginally more than would be expected from normal sampling variation.     

US strategic minerals: Policy options

The USA is becoming increasingly dependent on key strategic metals (such as chrome, cobalt, manganese and platinum-group metals) from politically unstable regions of the world. This dependence is the result of an inconsistent and fragmented US non-fuel minerals policy. Neglect of the US minerals industry has led to a decline in US mineral production and processing capabilities. Options for a comprehensive US non-fuel minerals policy include increased domestic production; increased substitution and recycling; a domestic stockpiling programme; and diversification of, and ensured access to, foreign sources of supply. These four options are examined and recommendations are made for increased mineral surveys of public lands, a regulatory review, domestic production of strategic minerals, tax incentives, conservation, stockpiling, and a foreign policy that will ensure security of supply.     

美国与欧盟关于PM2.5和臭氧的监管政策述评

分析了美国与欧盟关于PM_2.5和臭氧的监管政策的演变与现状。美国的监管政策以《清洁空气法》为主体,以国家层面管理为主导,以州为独立执行单位进行自主管理,这种制度能够更好地促进各州根据当地情况进行监管,充分调动其积极性;欧盟的监管政策由七个欧盟组织和机构共同进行监督、管理和调控,各成员国共同遵循2008/50/EC指令或更严格的本国标准。美国和欧盟的监管系统将监管主体定位在各州或各成员国,制定严格的标准,加强监测,做到高的公众告知程度,这些监管政策对中国PM_2.5及臭氧的监管政策及措施的调整提供了参考。     

Controls on Mercury and Methylmercury Deposition for Two Watersheds in Acadia National Park, Maine

Throughfall and bulk precipitation samples were collected for two watersheds at Acadia National Park, Maine, from 3 May to 16 November 2000, to determine which landscape factors affected mercury (Hg) deposition. One of these watersheds, Cadillac Brook, burned in 1947, providing a natural experimental design to study the effects of forest type on deposition to forested watersheds. Sites that face southwest received the highest Hg deposition, which may be due to the interception of cross-continental movement of contaminated air masses. Sites covered with softwood vegetation also received higher Hg deposition than other vegetation types because of the higher scavenging efficiency of the canopy structure. Methyl mercury (MeHg) deposition was not affected by these factors. Hg deposition, as bulk precipitation and throughfall was lower in Cadillac Brook watershed (burned) than in Hadlock Brook watershed (unburned) because of vegetation type and watershed aspect. Hg and MeHg inputs were weighted by season and vegetation type because these two factors had the most influence on deposition. Hg volatilization was not determined. The total Hg deposition via throughfall and bulk precipitation was 9.4 μg/m²/year in Cadillac Brook watershed and 10.2 μg/m²/year in Hadlock Brook watershed. The total MeHg deposition via throughfall and bulk precipitation was 0.05 μg/m²/year in Cadillac Brook watershed and 0.10 μg/m²/year in Hadlock Brook watershed.