Remediation of heavy-metal contaminated land by soil stabilization and groundwater extraction

• Main Authors: Hsien-Wei Li, 李賢偉
• Other Authors: Jimmy C. M. Kao
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/2s549q

碩士 === 國立中山大學 === 環境工程研究所 === 102 === In Taiwan, most of the listed polluted sites by Taiwan Environmental Protection Administration are contaminated by heavy metals and the polluted media are mainly soils. In this study, the design factors and operational parameters for the remedial systems for a heavy-metal polluted groundwater site were investigated. At this site, the soils also contained low levels of Zn and Ni (lower than the soil standards). However, groundwater contained high levels of Ni, Zn, and Cr. In this study, groundwater containment and soil stabilization technologies were applied for site remediation. The site soils were mainly silt and sandy silt. Clay layer was located around 11 m below the land surface. The hydrologic conductivity was around 10-3 cm/s, which indicating that the site soil had good permeability. Preliminary test results showed that no heavy metal dissolution occurred when the soil pH was adjusted to 5.5. Investigation results showed that the site containment could effectively minimize the plume migration and reduce the impact of contaminants on site environment. Groundwater extraction could also reduce the heavy metal concentrations in groundwater. Soil stabilization could result in the increase in soil pH and achieve the soil remediation objective. X-ray fluorescence was used for on-site soil analysis to evaluate the remedial effectiveness.