Application of Monitoring Data forGiardia andCryptosporidium to Boil Water Advisories

Despite the problems associated with analyzing water samples for Giardia cysts and Cryptosporidium oocysts, the data can be very useful if their strengths and weaknesses are understood. Two municipalities in northern Ontario, Temagami and Thunder Bay, both issued boil water advisories for Giardia contamination. Data from these two cities are compared to show that only one municipality experienced a real outbreak, whereas the other did not. The concentration of Giardia cysts was much higher than background during the outbreak at Temagami, and the postoutbreak concentrations of cysts were very similar to the long-term average cyst concentration at Thunder Bay. The waterborne outbreak of giardiasis at Temagami was characterized by consistent positive results from water samples, concentrations two to three orders of magnitude higher than normal, and an obvious increase in the number of cases of giardiasis in the population. No outbreak was experienced at Thunder Bay, but a boil water advisory (BWA) was set in place for more than a year on the basis of a single sample from Loch Lomond in which only two cysts were detected but the sample equivalent volume was low. This gave the impression of a sudden increase in concentration, but 39 of 41 subsequent samples were negative. Additional factors that led to a BWA at Thunder Bay are described, and recommendations are presented to help determine when a BWA is necessary and when it should be rescinded.     

Effects of Etiological Agent and Bather Shedding of Pathogens on Interpretation of Epidemiological Data Used to Establish Recreational Water Quality Standards

The overall goal of the study reported herein was to use techniques in the field of risk assessment (specifically a state-space population dynamic model of disease transmission within recreational waters) to explore the relative significance of (1) active shedding of microorganisms from bathers themselves, and (2) the type and concentration of etiological agent on the observed heterogeneity of the incidence of illness in epidemiological studies that have been used to develop ambient water quality criteria. The etiological agent and corresponding dose ingested during recreational contact was found to significantly impact the observed incidence of illness in an epidemiological study conducted in recreational water. In addition, the observed incidence of illness was found not to necessarily reflect background concentrations of indicator organisms, but rather microorganisms shed during recreational contact. Future revisions to ambient water quality criteria should address the etiological agent, dose, and the significance of microbial shedding relative to background concentrations of pathogens and indicator organisms in addition to the incidence of illness and concentration of indicator organisms. Without a quantitative assessment of these additional variables, study findings may potentially be site specific and not representative of the health risks associated with specific indicator concentrations in all recreational waters.     

青州沙溪特大桥水中墩双壁钢围堰施工技术

由于水中墩双壁钢围堰施工难度相对较大，施工过程的控制比较麻烦，因而应根据工程地质状况及技术条件决定采用与否。介绍了青州沙溪特大桥水中墩双壁矩形钢围堰的施工过程，包括钢围堰的制作、拼装过程，墩位清基与基床整平过程，浮运及定位下沉过程，钢平台搭设及钢护筒沉放等过程。     

高含NaAc废水综合利用试验研究

某制药厂排放的废水ＮａＡｃ 含量较高，本试验采用廉价的硫酸等进行反应，综合回收醋酸、硫酸钠，反应残留母液还可制成缓蚀剂．既有经济价值又避免环境污染．     

国外流域水资源管理模式演进及对我国的借鉴意义

通过回顾国外流域水资源管理模式的演进历程，联系国外水资源管理理论与实践背景，对其管理模式、管理政策与管理方法的科学性和有效性进行了评析。研究和总结了国外水资源管理的未来发展趋势和经验教训，在分析我国水资源管理现状的基础上，系统地讨论了国外水资源管理模式与方法对我国未来水资源管理的借鉴意义。     

Safe drinking water and satisfaction with environmental quality of life in some oil and gas industry impacted cities of Nigeria

The availability and safety of drinking water and the environmental quality of life was investigated in five cities located in an oil-producing area of Nigeria using questionnaire-based scales, discussion and laboratory tests. Polythene-packaged sachet water and commercial and non-commercial private boreholes largely met the drinking water requirement of the cities. Consumption of sachet water was high (14.0–20.0 points vs. 25.0 points) but regression analysis indicated strong negative relationships with income group (β = −0.75, P < 0.005) and educational level (β = −0.77, P < 0.005) of respondents (658). Private borehole water was prevalent (18.7–19.9 vs. 20.0) while public water supplies were almost non-existent (4.8–5.6 vs. 20.0) in the cities. Vulnerability to contamination in all water sources was indicated following unacceptable counts of total and faecal coliform bacteria in 10–62.5 and 3–25% of samples, respectfully. Respondents were not satisfied with environmental quality of life indicated by the quality of housing, school, health services, refuse disposal, recreation, streetlight, transport and police (3.43–4.01 vs. 10). It is concluded that modernization and industrialization due to the oil and gas industries, tended to increase individualization to the negligence of common services as evidenced by the preponderance of private boreholes and sachet water.     

老子教育思想阐释与分析批判

老子思想的核心是“道” ;老子教育思想的目的是要培养“孔德”(得道 )的人 ;其教育的主要内容是“水”和“赤子”(婴孩 ) ;其教育的原则和方法是无言之教等。本文进行了四个方面的批判扬弃 ,充分肯定了老子教育思想给我们今天的教育的反面和正面的启迪意义     

建筑给水塑料管现状及对比研究

介绍了建筑给水塑料管的发展现状 ,并对PAP管、PE -X管和PP -R管的应用特点作对比研究     

锅炉水中氯离子的自动测定系统研究

介绍了电厂锅炉水中氯离子的测定原理与检测系统，从而完成氯离子的自动测定．本系统可以连续在线监测锅炉供水的氯离子浓度等，为锅炉的安全生产与自动控制提供了条件，采用改进后的PH计作为在线氯离子计，以代替原来的人工检测，整个系统检测数据可靠，有效地提高氯离子检测的准确性．     

Reducing Drinking Water Supply Chemical Contamination: Risks from Underground Storage Tanks

Drinking water supplies are at risk of contamination from a variety of physical, chemical, and biological sources. Ranked among these threats are hazardous material releases from leaking or improperly managed underground storage tanks located at municipal, commercial, and industrial facilities. To reduce human health and environmental risks associated with the subsurface storage of hazardous materials, government agencies have taken a variety of legislative and regulatory actions—which date back more than 25 years and include the establishment of rigorous equipment/technology/operational requirements and facility‐by‐facility inspection and enforcement programs. Given a history of more than 470,000 underground storage tank releases nationwide, the U.S. Environmental Protection Agency continues to report that 7,300 new leaks were found in federal fiscal year 2008, while nearly 103,000 old leaks remain to be cleaned up. In this article, we report on an alternate evidence‐based intervention approach for reducing potential releases from the storage of petroleum products (gasoline, diesel, kerosene, heating/fuel oil, and waste oil) in underground tanks at commercial facilities located in Rhode Island. The objective of this study was to evaluate whether a new regulatory model can be used as a cost‐effective alternative to traditional facility‐by‐facility inspection and enforcement programs for underground storage tanks. We conclude that the alternative model, using an emphasis on technical assistance tools, can produce measurable improvements in compliance performance, is a cost‐effective adjunct to traditional facility‐by‐facility inspection and enforcement programs, and has the potential to allow regulatory agencies to decrease their frequency of inspections among low risk facilities without sacrificing compliance performance or increasing public health risks.