Eisenhower memorial tunnel. Edwin C. johnson bore . . Mining of west top section of second bore completed. Post Ap 26, 1977 p.26 Excavation starts on second bore. Post My 21, 1977 p.10 Mining to start early in August. Post Jy 13, 1977 p.2 Mining started on east section of second bore. Post Ag 3, 1977 p.42