南强讲座第404期
Managing Risks from Contaminated Sediments
（污染沉积物的风险管理）
时间：6月11日（星期五）19:00-20:30
地点：图书馆五楼南强报告厅
演讲者：Danny D. Reible教授
Bettie Margaret Smith Chair Professor of Environmental Health Engineering, University of Texas at Austin
美国德克萨斯大学环境健康工程方向首席科学家
教授个人简介：
Danny D. Reible教授是国际知名的环境工程学家，于1982年获美国加州理工化学工程博士学位，1986年被美国工程教育学会授予“工程学科杰出教育者”奖励，目前已发表了100多篇科技论文，撰写了《环境工程的基础》、《环境迁移扩散模型》等专著、教材。Reible教授现任德克萨斯大学环境健康工程方向首席教授及美国有害物质研究中心主任，同时任职于美国国家科学研究委员会环境与毒理学研究理事会，并为美国众议院水资源与环境委员会的污染沉积物管理决策提供科学咨询。
教授个人主页：
http://www.ce.utexas.edu/reiblegroup/biography.html
讲座内容摘要：
Managing Risks from Contaminated Sediments
Contaminated sediments pose some of the most difficult problems for site remediation and risk management. Sediment sites are typically large in volume and contain relatively low levels of contamination. Because of the extent and difficulties of managing contaminated sediments, literally billions of dollars often depend upon the selection and implementation of appropriate remedial decisions. As highlighted by a recent National Research Council study, traditional approaches calling for the removal of sediments for subsequent treatment or disposal often leave significant residual contamination and generate large amounts of water that must be treated. Thus invasive removal options are often less protective of the environment in addition to being more costly than other approaches. As a result, efficient and effective management of contaminated sediments has often been a contradiction in terms.
A variety of research has been undertaken over the past decade, however, that has improved our ability to assess and effectively manage contaminated sediments. Key to this improvement is a better understanding of the risks of contaminated sediments, both with time and space. Contaminated soils and sediments are normally regulated on the basis of bulk solid concentrations. This phase is normally neither mobile nor available to biota and a better indicator of exposure and risk is often the concentration in the mobile phase, typically the interstitial water. For strongly hydrophobic contaminants, such as low solubility organic compounds, measurement of the interstitial water concentration has normally been difficult and hence reliance on the regulatory default has often been necessary. In addition, in-situ management of such contaminants is often accomplished through containment systems and the low mobility of these compounds has made it difficult to assess and monitor containment effectiveness. Recently, however, passive gradient samplers have come available that allow rapid and sensitive measurement of interstitial water contaminants and their migration. This seminar will summarize efforts to develop and apply a field deployable solid phase microextraction (SPME) sampler for profiling interstitial water concentrations of hydrophobic organic contaminants. Laboratory studies were used to evaluate kinetics and equilibrium uptake in the fibers and compare to bioaccumulation in benthic organisms. Conclusions are drawn as to the applicability of interstitial water concentrations for assessing availability and uptake of PAHs and PCBs. The approach was also demonstrated in the field including comparison of uptake in caged organisms to SPME measurements and the use of gradients in the interstitial water concentration for the assessment of the effectiveness of demonstration sediment caps in the Anacostia River, Washington, DC.
