Fate of trace contaminants at waste sites

从废物场址释放的无机和有机污染物可导致用于供水的地下水的恶化和污染物向地表水体的排放。污染物从源区的释放和运输在空间和时间上都是不同的，这取决于物理和地球化学过程的复杂组合。在一些场址，最高浓度的污染物是在废物处置的头几十年里释放出来的，而在其他场址，要经过几十年才能观察到最高浓度。在一些地点，污染物可以迁移数公里，而在另一些地点，污染物迁移的距离可能仅限于几十米。该研究项目旨在量化控制固体和液体废物场地污染物长期释放的物理和地球化学过程。将在旧矿山和炼油厂废料场址进行水文地质和地球化学研究。这些场地的特点往往是溶解金属的浓度非常高，超过10,000毫克/升，在废物处理停止后的几十年内可能会释放出来。实验室和现场测量物理水和气的输送过程和水，气和固相地球化学反应将进行。这些结果将用于改进计算机模型，以开发污染物运输的长期预测。该研究计划的第二个组成部分将侧重于控制废水处理场污染物运输的物理和地球化学过程。来自家庭、农业和商业的废水通常被处理在瓦片床中或通过其他方式，并被允许渗入地下，导致大量受污染的地下水的发展。主要和微量污染物（包括药物化合物、个人护理产品和病原体）的运输将在整体羽流化学的背景下进行评估。了解上述过程是为受污染的固体和液体废物场地制定有效和长期补救计划的一个基本方面。

The release of inorganic and organic contaminants from wastes sites can lead to the deterioration of groundwater used for water supply and discharge of contaminants to surface water bodies. The release and transport of contaminants from source zones vary spatially and temporally depending on a complex combination of physical and geochemical processes. At some sites, the highest concentrations of contaminants are released during the first few decades of waste disposal, whereas at other sites, many decades will pass before the highest concentrations are observed. Contaminants can be transported several kilometers at some sites, whereas at others the distance of contaminant migration might be limited to only 10s of meters. This research program is directed at quantifying the physical and geochemical processes controlling the long-term release of contaminants from solid and liquid waste sites. Hydrogeological and geochemical studies will be carried out at old mine and refinery waste sites. These sites are often characterized by very high concentrations of dissolved metals, in excess of 10,000 mg/L, which can be released over many decades after waste disposal ceases. Laboratory and field measurements of physical water and gas transport processes and water, gas and solid phase geochemical reactions will be made. These results will be used to refine computer models to develop long-term predictions of contaminant transport. A second component of the research program will focus on physical and geochemical processes controlling contaminant transport from wastewater disposal sites. Wastewater from domestic, agricultural, and commercial sources is routinely disposed of in tile-beds or by other means and allowed to infiltrate into the subsurface leading to the development of large plumes of contaminated groundwater. The transport of major and trace contaminants, including pharmaceutical compounds, personal care products, and pathogens, will be evaluated in context of the overall plume chemistry. The understanding of the above processes is a fundamental aspect of the development of effective and long-term remediation schemes for contaminated solid and liquid waste sites.