Abstract: Employee #1 was installing a 3 in. PVC riser pipe within 1 ft of a concrete block wall on the east side of a single family dwelling under construction. The wall, which was in the basement, was 10 in. wide by 88 in. high by 60 ft 8 in. long. Another employee, who was close by, heard the 2 in. by 10 in. wooden wall braces breaking and told Employee #1 to get out because the wall was coming down. The basement walls had been finished 8 days earlier and the backhoe operator had just finished backfilling the outside of the east wall. Employee #1 was trapped under the block wall and was manually dug out by two coworkers. He suffered a broken pelvic bone and sustained bruises and contusions on his entire body.