No. 79-1237. Argued February 8, 1980. Decided October 3, 1980. Theodore J. Martineau, Philadelphia, Pa. (L. Jean Shannon, Ballard, Spahr, Andrews Ingersoll, Philadelphia, Pa., Jack W. Burtch, Jr., Hunton Williams, Richmond, Va., on brief), for petitioner. James Y. Callear, N.L.R.B., Washington, D.C. (John S. Irving, Gen. Counsel, John E. Higgins, Jr., Deputy Gen. Counsel, Robert E. Allen, Acting Associate Gen. Counsel, Elliott Moore, Deputy Associate Gen. Counsel, Janet C. McCaa, N.L.R.B., Washington