Water-Holding Properties of Clinoptilolite/Sodium Polyacrylate-Modified Compacted Clay Cover of Tailing Pond.

Clinoptilolite and sodium polyacrylate (Na-PAA) were used as water-retaining agents to improve the water-holding capacity of compacted clay cover (CCC). The optimum moisture content and Atterberg limits of the CCC modified by clinoptilolite and Na-PAA were studied. The soil-water characteristic curve (SWCC) of the CCC modified by clinoptilolite and Na-PAA was studied.

Field Investigation of Effect of Plants on Cracks of Compacted Clay Covers at a Contaminated Site.

Compacted clay covers (CCCs) are effective in restricting the upward migration of volatile organic compound (VOC) and semi-volatile organic compound (SVOC) vapors released mainly from unsaturated contaminated soils and hence mitigate the risks to human health. Desiccation cracking of CCCs would result in numerous preferential channels. VOC or SVOC vapors can prefereially migrate through the cracks and emit into the atmosphere, exposing threats to human health and surrounding environmental acceptors.

Microbial induced carbonate precipitation for immobilizing Pb contaminants: Toxic effects on bacterial activity and immobilization efficiency.

Microbial induced carbonate precipitation (MICP) is a natural bio-mediated process, which has been explored for soil stabilization and heavy metals immobilization in soil and groundwater. Previous studies have shown that MICP is capable of immobilizing various heavy metals including lead (Pb). However, most studies focus merely on the immobilization of heavy metals with relatively low concentration.