MODESTO -- Stanislaus County and Modesto are in a legal dispute regarding who is responsible for environmental work and the cleanup of pollutants that are released from the former Geer Road landfill.
In April 2011, state authorities ordered the county to take more aggressive cleanup action for a toxic groundwater plume, which has moved slowly from the closed landfill to the edge of the Tuolumne River.
The former garbage dump lies several miles southeast of Modesto and about a mile northeast of Hughson.
The county claimed in a lawsuit last year that Modesto is responsible for all or part of the costs of dealing with toxic substances that continue to emanate from the buried garbage.
In May 2010, tests found dangerous concentrations of toxins in places under the 167-acre landfill, including vinyl chloride; 1,2 dichloroethane; and dichlorodifluoro-methane, also known as Freon-12. The first two chemicals are suspected of causing cancer.
Modesto was the largest generator of garbage that was taken to the Geer Road dump from 1970 through December 1990, when the landfill was closed. The city says in an August 2011 countersuit, however, that the county was responsible for cleanup costs.
The countersuit argues that a 1970 city-county agreement regarding the landfill spelled out that the county had full responsibility for the maintenance, operation and control of the garbage dump. City legal staff did not return calls Tuesday.
County Counsel John Doering said Tuesday that city and county officials have talked about settling the matter outside the courtroom. They are exploring whether their respective insurance policies could fund additional cleanup efforts.
"We believe that with the insurance resources available to the county and city, we will be able to resolve the issues out there," Doering said.
The county is required to submit a report to the state by Dec. 30 evaluating the best ways to clean the groundwater. The 2011 state order calls for a stronger cleanup effort and requires the county to better identify the spread of the contamination.
Monitoring wells show the toxic plume has migrated to the river, but is at a lower level than the river bottom, said Wendy Wyels, environmental program manager for the state's Central Valley Regional Water Quality Control Board.
Tests have not detected the pollutants in the nearby Tuolumne, and the plume has not crossed underneath to the south side of the river, county and staff officials said.
Jami Aggers, interim environmental resources director for the county, said staff members are working with consultants on the report due next month, so she could not estimate the cost of additional cleanup efforts.
As of 2011, the county had spent more than $7 million on cleanup operations and had mostly depleted a fund that has paid for closure costs. The county has used an extraction-well system on the property to collect and treat the contaminated groundwater. Another extraction system sucks out and burns gases that are emitted into the ground by the rotting garbage.
The county spent almost $2.2 million resolving lawsuits from neighbors whose wells were contaminated.
The Geer landfill was not constructed to present-day standards. The site is near a river and not far above groundwater, and it wasn't built with impermeable liners to keep pollutants from escaping.
Some officials are concerned the buried garbage will continue to emit pollutants that will pose a danger to people living nearby.
Doering said the ultimate solution could be the use of a "clean closure." Although it may be unfeasible to dig up and truck the old garbage to a disposal facility, there may be a way to inject material into the ground to seal off the landfill.
Bee staff writer Ken Carlson can be reached at firstname.lastname@example.org or (209) 578-2321.