Source-Controlled Remediation with Combined Geosynthetic and Cement-Based Solidification/Stabilization Systems

加拿大棕地遗址的修复是对加拿大经济和环境的严重挑战。加拿大联邦政府通过为期15年的联邦污染场地行动计划，已拨出35亿美元，用于评估和处理其确定的2.1万个地点。需要对这些地点采取经济和可持续的补救办法；如果潜在补救项目的成本过高，补救棕地地点的动机无疑会很低。这类工作的经济衍生产品意义重大。正如加拿大市政当局联合会在2009年指出的那样，每投资1美元用于棕地重建，平均就有3.8美元投资于经济。在加拿大，将受污染的土壤与水泥混合是一种正在得到推广的修复技术；最近的例子是悉尼焦油池项目修复70万吨受污染的沉积物，耗资5200万美元。这笔费用中的大部分与购买水泥有关。这项技术依赖于控制现场污染物的释放(即源头控制的补救措施)。然而，这项技术在加拿大的实施提出了几个问题：1)源头控制方法在加拿大经历冰冻/融化的寒冷地区将发挥多大作用？2)如何利用土工合成材料改进该技术，同时以较低的成本实施？本研究试图为这些问题提供一些答案。研究生(1名博士，1名硕士)将进行研究，考察污染土壤的水泥基固化/稳定化(CB S/S)处理的冻结/融化水力性能。其他人(2名博士，3名硕士)将研究土工膜和土工合成粘土衬里(即人造衬垫系统)作为炭黑S/S系统垂直截流和覆盖系统的长期适宜性，以降低整个修复系统的成本(即水泥百分比)，同时保持对污染物的长期源头控制。每个研究生都将接受加拿大强大的工程服务行业对技术知识和专业技能的培训。

The remediation of brownfield sites in Canada represents a serious challenge to the Canadian economy and environment. The federal government of Canada, through the 15-year Federal Contaminated Sites Action Plan, has allocated $3.5 billion to assess and deal with their 21,000 identified sites. Economic and sustainable approaches for remediation of these sites are required; if the cost of a potential remediation project is excessive, the motivation of remediating the brownfield site will undoubtedly be low. Economic spinoffs from this type of work are significant. As noted by The Federation of Canadian Municipalities in 2009, for every $1 invested in brownfield redevelopment, an average of $3.80 is invested in the economy. Mixing contaminated soil with cement is a remediation technique that is gaining traction in Canada; the most recent example being the remediation of 700,000 tonnes of contaminated sediment at the Sydney Tar Ponds Project at a cost of $52 million. Most of this cost relates to purchase of cement. This technique relies on controlling the release of contamination from the site (i.e. source-controlled remediation). However, implementation of this technology in Canada poses several questions: 1) How well will the source-control approach work for cold regions in Canada which undergo freeze/thaw? 2) How can the technology be improved with geosynthetics, yet implemented at lower cost? This research attempts to provide some answers to these questions. Graduate students (1 PhD, 1 Masters) will perform research examining the freeze/thaw hydraulic performance of cement-based solidification/stabilization (CB S/S) treatment of contaminated soil. Others (2 PhD, 3 Masters) will examine the long term suitability of geomembranes and geosynthetic clay liners (i.e. manufactured liner systems) as vertical cutoffs and cover systems for CB S/S systems in order to reduce the cost (i.e. percentage of cement) in the overall remediation system, yet maintain the long-term source-control of contaminants. Each graduate student will receive training in the technical knowledge and professional skills-sets in high demand by Canada's strong engineering services industry.