By Nancy Zuckerbrod
The Associated Press

WASHINGTON - The Justice Department is joining a lawsuit that alleges a subsidiary of Lockheed Martin Corp. illegally stored and disposed of radioactive and hazardous waste and defrauded the government while the company was a contractor at a nuclear facility in Paducah, Ky.

The Justice Department announced its decision Friday - four years after a plant worker, two retired employees and the Natural Resources Defense Council filed their suit in federal court in Kentucky.

"We're extremely pleased that they're intervening," said attorney Joseph Egan, who represents the workers and the environmental group. "In a case like this, it's very important to have the resources of the government behind you."

Lockheed Martin Energy Systems and its corporate predecessors conducted key operations at the uranium enrichment plant for the Energy Department from 1984 through 1998. The suit accuses the company of violating environmental laws by dumping radioactive waste and hazardous materials in plant landfills and nearby.

The suit also accuses the company of submitting false claims with the government to illegally obtain fees it didn't deserve. Whistleblowers are entitled to a share of any money recovered in such cases.

The suit doesn't put a dollar figure on the alleged wrongdoing. But one source close to the case, who spoke on the condition of anonymity, estimated the plaintiffs would seek more than $1 billion.

In a statement, Bethesda, Md.-based Lockheed Martin Corp. denied any wrongdoing. "We strongly believe that the allegations are without merit," the company stated.

The Justice Department declined to throw its support behind two of the lawsuit's allegations. Those include complaints that the company misled the government about how well it protected its workers from radiation and that the company introduced radioactively contaminated metals into interstate commerce.

A Justice Department spokesman declined to comment on the agency's strategy.

Egan said the statute of limitations had expired on the interstate commerce complaint, and he noted that a separate class-action lawsuit dealt with the worker exposure complaint.