Developing a Reactive Geocomposite to Remediate Contaminated, Subaqueous Sediments

这项研究项目的目标是开发一种新的土工合成覆盖层，以包含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覆盖在水下，或移走沉积物进行异地处理和/或储存。将开发的基于土工合成材料的反应性盖子将提供与传统盖子相同的隔离，但也将：提供一个能够吸收和有效中和目标污染物的补救层；阻止细小的浮泥颗粒的再悬浮；并作为稳定的保护性基础材料。在开发出土工合成材料原型设计后，将使用现有的大型固结设备进行一系列小试，以评估每种土工合成材料的过滤相互作用和补救效果。使用三种不同粒度的土壤和两种污染物进行的测试将表明修复的量、污染物/颗粒再悬浮以及土工复合材料在长期性能方面的局限性。土工合成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。这项研究将证明这一概念在试验台规模上的可行性，并作为现场规模实施和建模的基础。

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.