The U.S. Environmental Protection Agency and the state Department of Health have completed a Superfund Removal Program cleanup removing over 814 tons of contaminated soil from residential and commercial property on Kauai. The site was once a pesticide mixing and storage area at the former Kilauea Sugar Mill.

“As a result of this toxic soil cleanup, the local residents are safer and the environment is better protected,” said Jared Blumenfeld, EPA’s Regional Administrator for the Pacific Southwest. “This joint effort is an example of the success achieved by the state’s program targeting old pesticide areas that have the potential to harm nearby communities.”

The removed soil contained residues of arsenic and dioxin from the pesticides stored and mixed at the site. Soil testing found elevated levels of the contaminants in a stormwater drainage ditch behind a commercial warehouse and at two adjacent residential properties. Sampling of other properties showed that surface and subsurface soils did not pose a health risk.

In addition to backfilling the area with new clean soil, the drainage ditch was capped with a concrete barrier. Throughout the process, over 230 air samples were taken that showed no detection of any contaminants being released by the work. The removed soil was safely disposed of at the Kekaha Landfill, which is permitted to accept chemically contaminated soils. The levels of contamination in the soil were relatively low, requiring no treatment.

Inorganic arsenic is a known human carcinogen and short-term exposure of humans to high levels of dioxins may result in skin lesions, such as chloracne and patchy darkening of the skin and altered liver function. Long-term exposure is linked to impairment of the immune system, the developing nervous system, the endocrine system and reproductive functions.