An aide to U.S. Sen. Joseph R. Biden Jr., D-Del., has been appointed administrator of EPA Region III, which oversees Pennsylvania, Maryland, Delaware, Virginia, West Virginia and Washington, D.C..

W. Michael McCabe, 43, replaces former regional administrator Peter Kostmayer, a former Pennsylvania congressman who was fired from the environmental job earlier this year after disagreements with EPA Administrator Carol Browner. All of the Bay watershed, except the northernmost portion of the Susquehanna River drainage in New York, is in Region III.

McCabe's appointment to the Philadelphia-based office became effective July 17. He has worked for Biden for eight years, most recently as spokesman and projects director in Delaware.

Browner lauded McCabe's experience in dealing with environmental issues, including involvement with Delaware rivers and the state's clean air plan.

Before his work with Biden, McCabe served as staff director for the House Subcommittee on Energy Conservation and Power, which had oversight jurisdiction on nuclear power, utility regulation, energy conservation and renewable energy.

In 1980, he was coordinator of Environmentalists for President Carter, working to organize environmental activists in 10 key electoral states. From October 1979 to May 1980, he was executive director of Earth Day `80, organizing the national celebration of the 10th anniversary of Earth Day. And from 1976 to 1979, he was staff director of the Environmental and Energy Study Conference in Congress, a bipartisan legislative research organization. Before that, he was a legislative assistant to former Sen. Gary Hart, D-Colo.

In the mid-1980s, he worked as a commercial real estate agent in Delaware, specializing in buildings suited for historic rehabilitation and investment.