A trial to determine whether a nuclear fuel processing plant is responsible for eight cases of cancer could set the tone for more than 200 related cases.

Eight people who have cancer or represent others who died of the disease have sued Atlantic Richfield Co., Babcock & Wilcox Co. and B&W Nuclear Environmental Services Inc., the successive operators of the plant in Apollo, about 30 miles northeast of Pittsburgh.The trial, which opened Monday, is expected to take three weeks.

The lawsuit, filed in 1994, will serve as a test for more than 90 personal injury cases, about 120 property damage cases and a class-action lawsuit seeking medical monitoring for residents. The other cases are on hold.

The plant processed uranium as fuel for nuclear reactors and submarines from 1957 to 1978. In the early 1990s, it was torn down, and more than 800,000 cubic feet of soil and debris were shipped to a radioactive disposal site.