CAREER: Microbial-Based Engineering Approaches for Prevention and Treatment of Acid Mine Drainage: An Integrated Research and Education Plan

本提案所述的研究旨在研究通过刺激异养微生物生长来减少原位酸形成的方法。据推测，如果给予适当的条件（即可降解的有机碳源），异养细菌将能够在酸性矿山排水（AMD）地点与负责催化酸形成反应的铁氧化微生物竞争。这是一个尚未引起重视的领域，但有潜力作为补救和预防技术加以利用。本研究将对模拟极端环境下的微生物群落结构提供基础认识；然而，研究结果可以转移到其他受类似限制的极端环境中的社区动态。本研究将通过实验评估添加有机碳基质对断裂或生物膜系统中矿物氧化的影响。本研究的具体目标是：1。在高表面积体积比的实验室系统中，确定增强的异养微生物生长对嗜酸微生物氧化矿物的影响。2 .建立异养诱导防酸机制，确定在生物膜为主的系统中加强异养诱导防酸的适宜条件。3 .确定酸性环境下微生物铁还原和硫酸盐还原对酸性矿井排水生物修复的相对影响。评估有机碳底物添加对酸性生成的影响，在一个具有良好特征的AMD位点。拟议研究的长期和更广泛的科学和工程影响涉及开发预防和减轻酸性排水的新方法。虽然目前的应用主要集中在处理酸性、含金属的水流——通常是利用化学沉淀——但拟议的研究将试图在需要处理之前在原地防止酸的形成。虽然拟议研究的主要目标是首先防止酸的产生，但也将努力确定实现原位铁和硫酸盐还原的功效，特别是在低温环境中。与这个项目有关的科学推广活动将包括PI参加旨在教育公众了解与酸性矿井排水有关的问题的区域公众会议。PI已经与加州地区水质控制委员会（Lahonton地区）的监管机构和水质科学家建立了工作关系，并将与这些人合作传播实验结果。本研究的更广泛的基于教育的含义包括开发交互式实验，以纳入移动工程教育实验室（me2l）。要求资金支持本科生设计和建造移动实验室的互动展示。除了对ME 2.0项目有用之外，这些演示还将被纳入UNR的工程日和科学日项目，这两个项目旨在让高中生认真思考科学和工程方面的职业。除了这些基于外展的教育目标之外，PI还建议开发环境工程本科和研究生系列课程，在工程课程中介绍环境微生物学的基础和应用方面。

0239314 Marchand The research described in this proposal aims to study methods for minimizing acid formation in situ by stimulating heterotrophic microbial growth. It is hypothesized that if given the appropriate conditions (namely, a degradable organic carbon source), heterotrophic bacteria will be able to out-compete the iron-oxidizing microbes responsible for catalyzing acid-forming reactions at acid mine drainage (AMD) sites.This is an area that has not achieved much attention and has the potential to be utilized as both a remediation and prevention technique. The proposed research will provide fundamental understanding of microbial community structure in a model extreme environment; however, results may be transferable to community dynamics in other extreme environments that are subject to similar constraints.This investigation will experimentally evaluate the influence of supplemental organic carbon substrate addition on mineral oxidation in fractured or biofilm-based systems. The specific objectives of the research are:1. Identify the influence of enhanced heterotrophic microbial growth on mineral oxidation by acidophilic microbes in laboratory systems with a high surface area to volume ratio.2. Establish the mechanism(s) involved in heterotroph-induced prevention of acid generation and determine the appropriate conditions to enhance heterotroph-induced prevention of acid generation in biofilm-dominated systems.3. Identify the relative influence of microbial iron and sulfate reduction in acidic environments for bioremediation of acid mine drainage.4. Assess the influence of organic carbon substrate addition on acid generation at a well-characterized AMD site.The long term and broader scientific and engineering impacts of the proposed research involves the development of new methods for both prevention and mitigation of acidic drainage. While current applications focus on treatment of acidic, metal-containing water streams - typically utilizing chemical precipitation - the proposed research will attempt to prevent acid formation in situ before treatment is required. While a primary goal of the proposed research is to prevent acid generation from occurring in the first place efforts will also be made to identify the efficacy of achieving in situ iron and sulfate reduction, particularly in low temperature environments.Scientific outreach activities associated with this project will include participation of the PI in regional public meetings aimed at educating the public about issues associated with acid mine drainage. The PI has already developed a working relationship with regulators and water quality scientists at the California Regional Water Quality Control Board - Lahonton Region and will work with these individuals to disseminate experimental results.The broader education-based implications of this research involve the development of interactive experiments for incorporation into the Mobile Engineering Education Laboratory (ME 2 L). Funds are requested to support undergraduate students while they design and build interactive displays for the mobile lab. In addition to their utility for the ME 2 L program, these demonstrations will also be incorporated into Engineering Day and the Science Day programs at UNR, two programs aimed at getting High School students to think seriously about careers in science and engineering. In addition to these outreach-based education goals, the PI has also proposed to develop an undergraduate and graduate coursework series in environmental engineering that introduces fundamental and applied aspects of environmental microbiology in an engineering curriculum.