Fate of contaminants in groundwater and development of passive remediation systems

遗留的人为活动释放的污染物导致加拿大和世界各地许多地方的地下水、土壤和沉积物受到大规模污染。例如，采矿和制造活动导致有毒元素的释放，包括砷、镉、钴、铜、钼、镍、铅、汞、锌和钒，这些元素现在已造成水质退化或在污染源地区下游的土壤和沉积物中积累。由于污染的规模，需要采取昂贵的控制措施，以最大限度地减少供水和受影响生态系统的进一步退化。在过去的几十年里，已经开发了许多修复地下水、沉积物和土壤的方法，并取得了进展。就地修复技术通常应用于几公里以内的污染场地。

The release of contaminants from legacy anthropogenic activities has resulted in large-scale contamination of groundwater, soils and sediments at many locations in Canada and around the world. As an example, mining and manufacturing activities have led to the release of toxic elements, including As, Cd, Co, Cu, Mo, Ni, Pb, Hg, Zn, and V that have now caused degradation of water quality or have accumulated in soils and sediments downstream from source areas. Due to the scale of the contamination, costly controls are required to minimize further degradation of water supplies and affected ecosystems. A number of approaches have been developed for remediating groundwater, sediment and soils and advances have been made over the past several decades. In situ remediation techniques are generally applied at contaminated sites that are less than several km