A US appeals court ruled on Friday that Shell Oil Co. and two railroads were liable for disputed cleanup costs at a toxic waste site in California's central valley.

A three-judge panel at the US Court of Appeals for the Ninth Circuit in San Francisco reversed a federal district court's finding that Shell, Burlington Northern & Santa Fe Railway and Union Pacific Transportation Co. were liable for only a minor portion of the total cleanup bill in the town of Arvin near Bakersfield.

The lower court had assigned a small share of liability to the railroads and Shell, but the appeals court said there was not enough evidence to apportion the harm.

The appeals court's decision did not specify the cleanup costs, but a lawyer who represented California's Department of Toxic Substances Control, a plaintiff in the case, estimated the cost at about $10 million.

The US Environmental Protection Agency also was a plaintiff in the case.

Agricultural chemicals were stored and distributed at a facility owned and operated by a now-defunct company, Brown & Bryant Inc., beginning in 1960.

Part of the land where the chemical operation was located was owned by two railroads that were predecessors to Burlington Northern and Union Pacific and some of the chemicals were supplied and delivered by Shell.

Leaks of the chemicals from storage tanks occurred and in 1983 Brown & Bryant was found in violation of hazardous waste laws. The EPA also found evidence of soil and groundwater contamination.

The EPA and the California Toxic Substances department filed actions in 1992 against the railroads and Shell for reimbursement of their investigation and cleanup costs. (Reuters)