Environment: Cracking the Highway Trust

John A. Volpe must enjoy confounding his critics. A millionaire highway builder and former Republican Governor of Massachusetts, he was expected to pave over America when he became Richard Nixon's Secretary of Transportation. Instead, Volpe has stopped highway projects that would have thrust through park land and destroyed low-income housing and historic buildings. Says he: "We've got to provide a national transportation system with the least possible harm to the environment."

This week, when Volpe presents the Highway Act of 1970 to the House Public Works Committee, he plans to go even farther. He proposes to open the hitherto untouchable—indeed, almost...