Public and occupational risks of the Nevada (USA) Test Site

The Nevada Test Site (NTS), north of Las Vegas, was the scene of hundreds of nuclear weapons tests over four decades, both above- and belowground. There is considerable interest, both in neighboring communities and elsewhere, in the risks it poses. Overall, the greatest risks are nonradioactive in origin, with occupational risks to employees and accident risks in transporting low-level nuclear wastes to the NTS from other Department of Energy (DOE) sites ranking highest. For radiation risks, that to workers handling radioactive materials is much higher than that to the surrounding population, either present or future. Overall, annual risks are small, with all fatalities approximately 0.008% of total Nevada deaths. At the NTS, the government spends about 5000 times more on radiation as opposed to nonradiation deaths. This suggests that at least some resources may be misallocated towards cleanup of public risks and that the occupational risk of cleanup may be much higher than the public risk. Thus risk may be multiplied by well-meaning programs.     

Information Management System for Site Remediation Efforts

/ Environmental regulatory agencies are responsible for protecting human health and the environment in their constituencies. Their responsibilities include the identification, evaluation, and cleanup of contaminated sites. Leaking underground storage tanks (USTs) constitute a major source of subsurface and groundwater contamination. A significant portion of a regulatory body's efforts may be directed toward the management of UST-contaminated sites. In order to manage remedial sites effectively, vast quantities of information must be maintained, including analytical dataon chemical contaminants, remedial design features, and performance details. Currently, most regulatory agencies maintain such information manually. This makes it difficult to manage the data effectively. Some agencies have introduced automated record-keeping systems. However, the ad hoc approach in these endeavors makes it difficult to efficiently analyze, disseminate, and utilize the data. This paper identifies the information requirements for UST-contaminated site management at the Waste Cleanup Section of the Department of Environmental Resources Management in Dade County, Florida. It presents a viable design for an information management system to meet these requirements. The proposed solution is based on a back-end relational database management system with relevant tools for sophisticated data analysis and data mining. The database is designed with all tables in the third normal form to ensure data integrity, flexible access, and efficient query processing. In addition to all standard reports required by the agency, the system provides answers to ad hoc queries that are typically difficult to answer under the existing system. The database also serves as a repository of information for a decision support system to aid engineering design and risk analysis. The system may be integrated with a geographic information system for effective presentation and dissemination of spatial data.     

主成分分析法在三江交汇处水质分析中的应用

本文应用主成分分析法，利用三江交汇处的三个断面从1984年到1998年的监测资料对交汇处的水质做分析，分析前先对量化数据标准化处理，处理后提取主成分，并且计算其贡献率和累计贡献率，再由相应的特征向量得到主成分的线性表达式。结果表明：五项影响因素中，三个断面桔水期均受亚硝酸盐氮的影响比较大，丰水期和平水期均受悬浮物和化学需氧量的影响比较大。交汇前，小南门断面的水质综合污染最严重，凉姜沟断面的水质综合污染最轻；交汇后，三江口断面的水质在两者的缓冲下，水质综合污染居中。则说明主成分分析法为河流的综合治理提供了科学依据。     

上海潜在滨海旅游资源调查及开发研究

上海市的海岸线蜿蜒460km，涉及5区1县，潜在滨海旅游资源亟待开发。为了更好地了解和掌握潜在上海滨海旅游资源的现状，结合上海独特的自然禀赋和社会经济条件，参照《旅游资源分类、调查与评价（国家标准）》（GB／T18972-2003），在对上海潜在滨海旅游资源普查的基础上，研究了上海潜在滨海旅游资源分类，分析了潜在滨海旅游资源特征和资源富集区状况，选划出上海应重点开发的6大潜在滨海旅游资源区，并分别就各资源区的开发对策与建议提出初步构想。     

新疆城市集中饮用水源地水质状况调查评价

随着经济社会的发展和人民生活水平的提高,人们对饮用水水质要求也日益关注,但目前城市饮水中普遍存在着水源不足、水污染、安全保障措施薄弱、应急能力低等诸多问题,加强城市饮用水水源地环境保护已经刻不容缓.对饮用水水源地水质状况调查评价为进一步查清我区城市水源地的水质现状、水源保护区内存在的环境问题以及污染源现状,科学制定饮用水水源地保护和管理对策和保障措施提供依据,并为后续饮用水源地环境保护规划工作奠定基础.     

首都大学生的自然灾害认知调查与减灾教育建议

2006年国际减灾日的主题是"减灾始于学校",了解学生的灾害认知水平有助于减灾教育工作的有效开展。以北京5所高校的大学生为调查对象,通过问卷方式调查大学生对自然灾害的关注程度、防灾意识、灾害理论知识、应急行为知识以及对减灾教育的看法。问卷统计结果表明:大学生总体的灾害认知水平较低,现行减灾教育方式和内容与学生的期望有较大偏差。在此基础上,提出了减灾教育内容要将学生"该知道的"与"想知道的"相结合,通过演练演习等方式提高学生的防灾应急实际技能等减灾教育建议。     

某厂化学装置爆炸对设备房结构的损坏——调查与模拟分析

在对某厂化学爆炸所作的现场调查的基础上，对设备房钢筋混凝土框架结构构件的受损状况进行了分类描述，采用有限元方法对框架结构在静力和爆炸冲击荷载下的反应进行了模拟分析，分析结果与现场调查情况基本一致，给出了一些有意义的结论。     

Contamination of Oxygen-Consuming Organics in the Yellow River of China

Contamination of oxygen-consuming organics (OCOs) was one of the most serious problems in the Yellow River of China. This study was conducted to analyze monitoring of the data on OCOs contamination for the river in 1980 and during 1992–1999 as well as examining the effect of suspended solids (SS) on chemical oxygen demand (COD_Mn) and biochemical oxygen demand (BOD₅) of river water. Several significant results have arisen from the study. First, COD_Mn and BOD₅ of the river water showed an increasing trend from the upper to the lower reaches of the mainstream. BOD₅ values of river water in 1992 were significantly higher than those in 1980 and showed an increasing trend during 1992–1999. Second, OCOs in river water of the mainstream was attributed mainly to point sources; the ratio of point to non-point sources of BOD₅ was about 2.81. The load from point sources showed an increasing trend during 1992–1998. In contrast, the load from non-point sources manifested a decreasing trend during this period; this was caused by the decreasing trend of SS content in river water. The total load of BOD₅ from point and non-point sources displayed an increasing trend during 1992–1998. Third, as the humic substances in SS can hardly be biologically oxidized in natural conditions but can be oxidized by chemical oxidants such as potassium permanganate, COD_Mn was not suitable for being regarded as a parameter reflecting the pollution degree of OCOs in river water with a high SS content.     

酒精在常见可燃地面材料燃烧痕迹特征规律研究

易燃液体燃烧痕迹识别对助燃剂放火火灾调查至关重要。选用丙纶地毯和PVC地板革作为纤维和塑料地板的代表,以工业酒精作为易挥发助燃剂的代表,研究酒精用量、灭火方式等对燃烧痕迹形成及痕迹稳定性的影响。通过与未加载酒精的痕迹对比,发现丙纶地毯因热稳定性较差,燃烧后往往能形成烧坑或烧洞,其燃烧轮廓以典型的灰化形式存在,加载酒精的部位熔融严重,与地面紧紧粘连在一起;PVC地板革因为表面光滑,酒精在其表面不断流淌,燃烧后会留下清晰的轮廓,类似于细线状的印痕,而地板革本身基本不会燃烧。燃烧熄灭的方式也会对其炭化程度、燃烧图痕、残余形状产生影响。     

Semi-analytical solution of two-dimensional sharp interface LNAPL transport models

In this paper, we present semi-analytical solutions for two-dimensional equations governing transport of Light Non-Aqueous Phase Liquids (LNAPL) in unconfined aquifers. The proposed model is based on sharp interface displacement and steady groundwater flow assumptions, where both the water–LNAPL interface and the LNAPL–air interface are represented as sharp interfaces. In the case of steady groundwater flow, these equations can be reduced to a two-dimensional nonlinear solute transport equation, with the LNAPL thickness in the free product lens being the primary unknown variable. The linearized form of this solute transport equation falls into the category of two-dimensional transport equation with time-dependent dispersion coefficients. This equation can be solved analytically for an infinite domain region. In this paper, the general form of the analytical solution for the transport equation, as well as the solutions for some specific cases are presented. To demonstrate the utility of the proposed solution, numerical results obtained for two example problems are discussed and presented comparatively with a finite-element solution and other more restrictive solutions available in the literature. Although the solutions discussed in this paper have some simplifying assumptions, such as sharp-interfaces between fluid phases, steady groundwater flow and homogeneous aquifer properties, the semi-analytical solutions presented in this study may be used effectively as bench mark solutions in evaluating LNAPL migration in the subsurface. These solutions are simple and cost effective to implement and may be used in the calibration of other more complex numerical solutions that can be found in the literature.