Evaluation of the Feasibility of Oyster-Shell and Eggshell Wastes for Stabilization of Arsenic-Contaminated Soil

Abstract

The objective of this research was to evaluate the feasibility of using oyster-shell and eggshell wastes for the stabilization of arsenic-contaminated soil. Artificial As(V) contaminated soil was mixed with 0~5% oyster-shell and eggshell wastes and each sample was incubated for 30 days in a controlled environment. The efficiency of each treatment was evaluated using various single extractants (1 N HCl, 0.1 N NaOH and 0.5 N ). The concentration of As(V) was reduced by 10% upon a 5% oyster-shell or eggshell waste treatments based on the Korea Standard Test method (1 N HCl extraction). Analogous trends were observed in the 0.1 N NaOH or 0.5 N extractions. In addition, the oyster-shell and eggshell waste treatments increased the pH of each soil from 6.54 (Control) to 7.62~7.94. The exchangeable Ca in each soil also sharply increased from 6.87 cmol(+)/kg (Control) to 12.77~20.18 cmol(+)/kg. Further research is needed to increase the effectiveness of the oyster-shell and eggshell waste for the stabilization of As(V) in the contaminated soil.