The U.S. Environmental Protection Agency (EPA) has decided to use a different and more efficient cleanup method to remove arsenic from 170,000 cubic yards of plant site soils at the Vineland Chemical Co. Superfund site in Cumberland County, N.J. The new method will reduce remediation time by years, reports the agency.
After careful testing and evaluation, EPA determined that the previously selected cleanup method, "soil flushing," would take over 40 years to meet the agency's cleanup goal for the soil in the most contaminated locations. The newly selected method, "soil washing," will reduce the arsenic levels to the cleanup goal in approximately two years.
The company made arsenic-based herbicides at the 54-acre property from 1950 to 1994, when it ceased operations. The plant soils contaminated the ground water, which in turn, conveyed the arsenic to the Blackwater Branch tributary, Maurice River and Union Lake water and sediments.
The process of soil flushing involves repeatedly forcing large volumes of ground water up through the contaminated soil to remove the arsenic. Soil washing involves excavating contaminated soil and running it through an above-ground system of washing cycles to separate out the arsenic in the soil. The results of EPA tests on soil flushing showed that it would take 17 to 20 years of flushing to reduce the average level of arsenic in the plant soils, which is 178 parts per million (ppm), to the cleanup goal of 20 ppm. The tests also showed it would take 38 to 43 years of flushing to reduce the level of arsenic in more highly-contaminated soils (1,720 ppm) to the cleanup goal.
"The switch in the soil cleanup plan will dramatically cut the time it takes to eliminate the arsenic at the site as a source of off-site contamination. Soil washing will take about two years rather than decades to finish the job and may result in significant cost savings in the end," said EPA Regional Administrator Jane M. Kenny.
EPA projects that it would have cost approximately $2 to 3 million a year to run the soil flushing system and that the total cost of soil washing will be $33.6 million and take about 24 months from start to finish.
In February 1994, a consent decree was entered in federal court to settle the liability for the contamination with the owner and only responsible party for the contaminated site, Miriam Schwerdtle. That settlement did not provide sufficient funds to carry out the remedy. The Superfund Trust will pay 90 percent and the State of New Jersey is responsible for 10 percent of the total cost of the cleanup. The New Jersey Department of Environmental Protection agrees with EPA's revision of the original cleanup plan.
The soil cleanup will be the latest step in a series of agency actions to address the environmental and public health problems posed by the site:
- In 1994, EPA fenced off the contaminated areas on the property and removed hazardous chemicals stored there, which significantly reduced the risk to human health and the environment posed by the site.
- In 1995, EPA completed the $3 million building demolition work at the site when more than 2,500 tons of building debris were shipped to federal and state approved facilities for disposal.
- Last summer, the $15.1 million ground water collection system began operations and is successfully reducing arsenic-contaminated ground water to the agency's cleanup goal.
Future agency actions, in addition to the site soils cleanup, will address the cleanup of arsenic-contaminated sediments in the tributary, river and lake.
edited by Sandy Smith ([email protected])