Horizontal Distribution Characteristics and Cause Analysis of Soil Contamination in Mining Area

Abstract

On the basis of the comparison and analysis of the chemical properties of contaminated and uncontaminated soils in a coalbed methane well site in Lyuliang city, the horizontal distribution characteristics of soil contamination caused by CBM produced water were discussed. Results indicate that both the moisture content and pH value of contaminated soil were higher than these of uncontaminated soil. The contaminated soil moisture content decreased first and then stabilized with the increase of the distance between the profile and CBM produced water, whereas, there was no significant change for pH value in horizontal direction. Na+ and Cl- were the main contaminantions in produced water and their content, in contaminated soil were obviously higher than these in uncontaminated soil. Herein, they varied greatly in horizontal direction at 0-10 cm depth, with no obvious change rule. Whereas, the values near the CBM produced water at 10-30 cm depth were higher and, changed obviously then tended to be stable with the increase of the distance between the profile and CBM produced water. Furthermore, the values decreased with increasing horizontal distance at 30-70 cm depth.

Keywords

• coalbed methane produced water
• soil
• contamination
• horizontal distribution