Abstract: At approximately 12:27 p.m. on January 4, 1993, Employee #1 was digging a trench along the north exterior of a residential structure. The trench was 5 ft 11 in. deep, 8 ft 4 in. long, and 2 ft 8 in. wide, with nearly vertical walls and an irregular floor. A spoils pile was placed adjacent to the edge of the trench. The north wall of the trench caved in from a point 12 in. below the grade, pinning Employee #1 against the masonry foundation of the residence, and burying him up to his knees. Employee #1 was removed from the trench and transported to the hospital, where he was treated and released. Employee #1 suffered contusions to his lower legs and swelling around his left knee.