Study of Differences in Phase Distribution in Soils Exceeding Soil Leaching Standards Due to Differences in Soil Type and Volatile Organic Compounds

Abstract

The Soil Contamination Countermeasures Act sets soil leaching standards for 13 volatile organic compounds. It is assumed that leaching standards vary greatly among soils and substances in terms of groundwater contamination and ease of remediation, even in the same standard exceedance conditions. In this study, the phase distribution of each contaminant in soil that exceeded the standard value by a factor of 2 was estimated. The groundwater contamination potential and ease of remediation were discussed based on soil property values and contaminant physical properties, as well as the significance of the standard value. The fact was found that the groundwater contamination potential is approximately twice as large in highly adsorptive soils, even under the same standard exceedance conditions, and that more than 90% of organic compounds such as chloroethylene in low adsorptive soils are distributed in the pore gas phase and the outer pore water phase, where they are more easily transported.