EVALUATION OF ERSENIC CONTAMINATION AT AGENT ORANGE/DIOXIN CONTAMINATED AREAS AND VICINITY AT BIEN HOA AIRBASE

Abstract

   Soil, sediment, surface water and ground water samples were collected at dioxin contaminated areas and vicinity at Bien Hoa airbase and analyzed by HVG-AAS method to evaluate the arsenic contamination level. Results show that among 25 soil and sediment samples, 13 samples have As concentrations from 1.1 to 21 times higher than allowance level. Most of them are sediment samples or soil samples taken from dioxin contaminated areas. The concentration of As in surface water and ground water were found to lie below the allowance level for ground water (0.05 mg/L) but some samples exceed the allowance level for drinking or domestic water (0.01 mg/L). The distribution of As concentration in water and sediment has a correlation: areas having low As concentration in sediment samples also have low As concentration in water. The contamination of As in soil, sediment and water might be originated from the Blue agent that American army used during Vietnam War, next to the natural origin and domestic activity.  This study has pointed out the possible risk of As contamination to areas and residence in the vicinity of Bien Hoa airbase, and might form a base to select a suitable dioxin remediation technology that also can remediate As in those places.