ANAEROBIC AND AEROBIC BIOREMEDIATION OF CHLORINATED ORGANIC COMPOUNDS

降低污染水体中氯代有机物的危害 地下水已经研究了我们的多学科团队的教师和 工程、微生物学和环境卫生专业的学生， 开发基于反应器的生物修复方法和独特的厌氧和 共代谢有氧富集。 退化的速度和程度 重要的氯化脂族和氯化芳族毒物 进行了调查，有助于开发实用的厌氧和 好氧生物降解工艺的应用。 共代谢变换 氯化脂肪族化合物的甲烷氧化菌，苯酚，甲苯，和 丙烷氧化剂已经为这些社区制定了比较比率， 了解代谢物毒性和竞争性抑制作用。 厌氧和好氧过程已经被研究，伴随着 使用细菌测定法测量残留毒性。 地上反应器处理污染物的局限性 来自非水相液体（NAPLs）的地下水已成为 越来越明显。 泵送的低NAPL去除效率和 冲洗方法可能需要几十年的时间来进行场地修复。 因此 提案中的研究重点已经转向理解 在NAPL附近的原位生物降解的生物刺激。 一 水文地质学家加入我们的团队，以协助设计和使用 对含水层微观世界的研究结果。 分子方法和近- 需要进行微观分析以了解生物刺激过程 其可显著增强NAPL的溶解和转运。 微生物研究的重点正在转向开发和使用 分子探针的博士后来协助这项工作。 该项目的主要目标是继续研究厌氧微生物 和好氧微生物富集，能够生物修复 氯代有机化合物，并研究其生物刺激在近 在NAPL附近。 将研究富集培养物和分离株， 研究微生物特性和工程应用。 原位研究需要开发含水层微观世界来模拟 非水污染区附近的地下生物修复和开发先进的 取样和了解化学和微生物的工具 对工程变量的响应。 生物动力学，富集 开发，含水层微观测试将在室内进行 温度，比我们以前的工作更接近地下水条件。 微生物活动的动力学建模将继续，但更大的 模拟活动将集中在t运输和生物降解， 多孔介质与生物刺激和地下水流。 建模将 被用来设计微观研究，然后解释和模拟他们的 结果并将结果外推到现场规模 生物修复 这项工作将提供强有力的，持续的合作 在工程、微生物学和健康领域的师生中， 以理工科为重

The reduction of hazards from chlorinated organics in contaminated groundwater has been studied by our multidisciplinary team of faculty and students from engineering, microbiology and environmental health by developing reactor-based bioremediation methods and unique anaerobic and cometabolic aerobic enrichments. Rates and extent of degradation of important chlorinated aliphatic and chlorinated aromatic toxicants have been investigated, helping to develop a practical range of anaerobic and aerobic biodegradation process applications. Cometabolic transformations of chlorinated aliphatic compounds by methanotrophs, phenol, toluene, and propane oxidizers has developed comparative rates for these communities and an understanding of metabolite toxicity and competitive inhibition effects. Anaerobic and aerobic processes have been investigated, accompanied by residual toxicity measurements using bacterial assays. The limitations of above ground reactors for treating contaminated groundwater resulting from non aqueous phase liquids (NAPLs) have become increasingly apparent. The low NAPL removal efficiency of pumping and flushing methods may require decades for site remediation. Consequently the research emphasis in the proposal has shifted to understanding biostimulation of in situ biodegradation in the near vicinity of NAPLs. A hydrogeologist is added to our team to assist in designing and using results of studies with aquifer microcosms. Molecular methods and near- microscale analyses are needed to understand the biostimulation processes that may significantly enhance dissolution and transport from NAPLs. Emphasis is being shifted in microbiological studies to development and use of molecular probes with a post-doctoral position to assist in this work. The broad objectives of the project are to continue to study the anaerobic and aerobic microbial enrichments that are capable of bioremediation of chlorinated organic compounds and to study their biostimulation in the near vicinity of NAPLs. Enriched cultures and isolates will be studied to investigate microbiological characteristics and engineering applications. The in situ studies require development of aquifer microcosms to simulate subsurface bioremediation near NAPLs and the development of sophisticated tools for sampling and understanding the chemical and microbiological responses to engineering variables. Biological kinetics, enrichment development, and aquifer microcosm testing will be done at room temperatures, closer to groundwater conditions than in our previous work. Kinetic modeling of microbial activity will continue, but a greater modeling activity will focus on the t transport and biodegradation in porous media with biostimulation and groundwater flow. The modeling will be used to design microcosm studies, then interpreting and simulating their results and extrapolating the results to field scale in situ bioremediation. This work will provide strong, continuing collaboration among faculty and students in engineering, microbiology and health sciences.