The Energy Department has agreed to pay a fine to the Environmental Protection Agency for failing to meet cleanup schedules at a nuclear weapons plant in Ohio, a government source said Friday night.

The source, who spoke on condition that he not be identified by agency, said the two government agencies would announce Monday that the department would pay $100,000 to EPA, and concede the environmental agency's authority to impose fines.The agencies also will negotiate a new cleanup schedule for the plant, the Feed Material Production Center at Fernald, the source said.

The fine represents a large reduction in the amount sought by EPA, which had reached $500,000 at the rate of $20,000 a week since the EPA announced its penalty plans last year.

EPA administrator William Reilly had said he would decide by Monday whether to go ahead with the fines, which posed the remarkable specatcle of the federal government fining itself - shifting money from one pocket to another.

The Energy Department, before now, had not conceded that it was subject to being fined by EPA.

At Fernald, the Energy Department signed a consent agreement that set out a series of required actions and a deadline for each. When the Energy Department signed the agreement, it also agreed in advance to the penalties that would kick in if the terms were not met.

The Fernald plant fabricated uranium components of nuclear weapons. It was closed in 1989 for a cleanup of uranium contamination of soil and groundwater and decades of process waste.

The government said later the plant would never reopen.