No. 81-1498. Argued January 6, 1982. Decided March 23, 1982. Diana Orantes Ceresi, Atty., Washington, D.C., with whom William A. Lubbers, Gen. Counsel, John E. Higgins, Jr., Deputy Gen. Counsel, Robert E. Allen, Acting Associate Gen. Counsel, and Elliott Moore, Deputy Associate Gen. Counsel, Washington, D.C., were on brief, for petitioner. S. Mason Pratt, Jr., Portland, Maine, with whom Donald W. Perkins, Pierce, Atwood, Scribner, Allen, Smith Lancaster, Portland, Maine, and Robert E. Jackson, West