Developing a Reactive Geocomposite to Remediate Contaminated, Subaqueous Sediments

本研究项目的目标是开发一种新的土工复合材料覆盖层，以容纳和修复受污染的水下沉积物。目前处理这类沉积物的做法是用干净的沉积物在水下封盖，或者将沉积物移出，进行移地处理和/或储存。即将开发的以土工合成材料为基础的活性帽将提供与传统帽相同的隔离，但也将提供一个补救层，将吸收并有效中和目标污染物；细泥沙颗粒的块状再悬浮；作为一种稳定的，保护性的基础材料。在土工复合材料原型设计开发完成后，将使用现有的大型固结装置进行一系列实验规模的测试，以评估每种土工复合材料的过滤相互作用和修复效果。使用三种不同粒度的土壤和两种污染物进行的试验将表明修复量、污染物/颗粒再悬浮量以及土工复合材料在长期性能方面的局限性。土工复合材料的修复过程将使用测试结果和现有的水下沉积物数据进行分析建模。该研究将证明该概念在实验规模上的可行性，并为现场规模的实施和建模奠定基础。

This goal of this research project is to develop a new geocomposite overlay to contain and remediate contaminated, subaqueous sediments. The existing state of practice to treat such sediments is either subaqueous capping with clean sediments, or removal of the sediment for ex situ treatment and/or storage. The geosynthetic-based, reactive cap to be developed will provide the same isolation as that of traditional caps, but will also: provide a remediation layer that will absorb and effectively neutralize target contaminants; block resuspension of fine dediment particles; and serve as a stable, protective foundation material. After prototype geocomposite designs have been developed, a bench-scale testing series will use an existing large-scale consolidation device to assess each geocomposite's filtering interactions and remediation effectiveness. Tests using three soils of different grain sizes and two contaminants will indicate the amount of remediation, contaminant/particle resuspension, and limitations of the geocomposite with regard to long-term performance. The geocomposite's remediation process will be analytically modeled using the test results and existing data on subaqueous sediments. The research will show the feasibility of this concept at the bench scale, and serve as a basis for field scale implementation and modeling.