Cleanup of soil, water OK'd
By Kevin Dayton
Advertiser Staff Writer
The U.S. Environmental Protection Agency has given final approval to a nearly $13 million plan to clean up chemical contamination of soil and groundwater at the Del Monte Corp. Superfund site in Central O'ahu.
Construction is under way or already completed on major pieces of the EPA cleanup plan, including a new facility to clean deep groundwater under the plantation. Another system has been operating since 1998 to decontaminate shallow groundwater using koa haole plants.
Soil and groundwater at the 6,000-acre plantation were contaminated by chemicals used to treat nematodes, a type of worm that infested pineapple fields.
The contamination was traced to a 495-gallon spill in 1977, as well as smaller spills in a pesticide-mixing area next to the plantation's housing camp, Kunia Village.
Tests in 1980 found chemicals in the drinking water from the Kunia Camp well, and the well was shut down.
The chemicals that tainted the water include ethylene dibromide or EDB, dibromochloropropane or DBCP, and dichloropropane or DCP. There is also trichloropropane or TCP, a solvent.
The EPA plan is designed to decontaminate the water to prevent the chemicals from spreading further underground, said Dean Higuchi, press officer for the EPA.
The cleanup is being paid for by Del Monte, he said.
Cleanup crews will use a soil vapor extraction process to remove chemicals trapped in the soil, and then treat the vapors with a carbon filtering process before the vapor is released.
Plants will be grown in a "cap" on the soil to reduce the amount of rainwater that filters through the untreated soil and carries chemicals to the groundwater below.
The shallow groundwater is being pumped from 20 to 100 feet deep to the surface and placed in lined treatment cells planted with the koa haole plants.
The EPA said data collected from the system shows it has been breaking down the contaminants.
Deep groundwater will be pumped from 800 feet down starting at the Kunia well, and will be cleaned using air stripping and carbon filters. Construction is expected to be complete in August on a plant to treat the deeper water.
Monitoring wells will be used to determine whether the clean- up reduces contaminants to within federal drinking water standards, the EPA said.
The EPA placed the Del Monte site on the national Superfund list in December 1994 because of concerns about contamination of the groundwater.
Reach Kevin Dayton at kdayton@honoluluadvertiser.com or (808) 935-3916.
