Sequestration and immobilization of metal and metalloid contaminants in sediments

沉积物中金属和类金属污染物的封存和固定

• 批准号: 7340851
• 负责人: Peggy A O'Day
• 金额: $ 28.74万
• 依托单位: UNIVERSITY OF CALIFORNIA, MERCED
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-30 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7340851
• 关键词: Address; Aging; Amendment; Basic Science; Bioavailable; Biological Availability; Biota; Caustics; Chemicals; Chemistry; Chronic; Collaborations; Complex; Condition; Data; Effectiveness; Elements; Encapsulated; Engineering; Environment; Food Chain; Health Hazards; Human; Immobilization; In Situ; Industry; Inorganic Sulfates; Investigation; Knowledge; Laboratories; Metals; Methods; Microscopic; Minerals; Modeling; Molecular; Organism; Phase; Public Health; Reaction; Research; Research Personnel; Roentgen Rays; Site; Solid; Synchrotrons; System; Technology; Thermodynamics; Time; Unspecified or Sulfate Ion Sulfates; Water; Work; aluminosilicate; base; bioaccumulation; day; design; environmental change; experience; novel; programs; remediation; research study

DESCRIPTION (provided by applicant): We propose basic research into the use of reactive amendments as an alternative remediation technology for hazardous metal and metalloid contaminants (namely, As, Hg, Se, Pb, Cu) of high priority in sediments at Superfund and other contaminated sites. These inorganic contaminants are particularly problematic because they do not degrade, they pose chronic health hazards to humans and organisms at low concentrations, they can be widely dispersed, they may be remobilized by changing environmental conditions, and many can bioaccumulate. Our approach is aimed at developing a molecular-chemical understanding of element sequestration mechanisms as a result of in situ reaction between the amendment and contaminated sediments. Using laboratory experiments with sediments from contaminated sites, we will investigate contaminant sequestration reactions and aging of the amendment products, with the aim of optimizing novel treatments to maintain or increase their stability as sedimentary environments change from oxidized to reduced. We will employ advanced spectroscopic and microscopic characterizations, including synchrotron X-ray methods, to determine contaminant element speciation, mechanism(s) of sequestration, and host phases at the molecular-to-microscopic scale in complex sediment mixtures. Our proposed work will also evaluate the feasibility of adapting existing engineering technologies for the delivery of reactive amendments to field systems. Because few remediation alternatives exist presently for contaminated sediments, this research will fill gaps in basic knowledge about the long-term fate of sediment amendments and their sequestered contaminants in subsurface environments, which presently contributes to a lack of acceptance and use of this approach. New methods for the sequestration and immobilization of inorganic contaminants in the environment will have positive impacts on public health by reducing their ability to enter the food chain and thus their potential bioaccumulation and biomagnification.

描述(由申请人提供)： 我们建议进行基础研究，使用反应性改良剂作为替代修复技术，以修复Superfund和其他污染场地沉积物中高度优先的有害金属和类金属污染物(即As、Hg、Se、Pb、Cu)。这些无机污染物特别有问题，因为它们不会降解，它们在低浓度下对人类和生物体构成慢性健康危害，它们可以广泛分散，它们可能会因环境条件的变化而重新动员，而且许多可能会生物积累。我们的方法旨在发展对元素隔离机制的分子化学理解，这是由于改良剂和受污染的沉积物之间的原位反应造成的。通过对污染场地的沉积物进行实验室实验，我们将研究污染物的固定反应和修正产品的老化，目的是优化新的处理方法，以在沉积环境从氧化到还原的变化中保持或增加其稳定性。我们将使用先进的光谱和显微表征方法，包括同步辐射X射线方法，在分子到微观的尺度上确定复杂沉积物混合物中的污染物元素形态、隔离机制(S)和宿主相。我们拟议的工作还将评估采用现有工程技术对外地系统进行被动修正的可行性。由于目前对受污染的沉积物几乎没有修复替代方案，这项研究将填补关于沉积物改良剂及其在地下环境中的隔离污染物长期去向的基本知识空白，这是目前对这种方法缺乏接受和使用的原因之一。在环境中隔离和固定无机污染物的新方法将减少它们进入食物链的能力，从而减少其潜在的生物积累和生物放大作用，从而对公众健康产生积极影响。