Abstract: On September 21, 2001, Employee #1 and a coworker, both unlicensed day laborers of Kazem Paya, were going to backfill a retaining wall by hand. The retaining wall was located on a homeowner's property. At the time of the accident, Employee #1 and the coworker were clearing out debris and soil behind the wall. The debris and soil accumulated at the base of the wall since the initial excavation was done. The wall had 9 ft to the foundation. Employee #1 and the coworker were working at the end of the wall on both sides. While Employee #1 was working on the west side of the wall, the soil where the hill had been excavated rolled down and buried Employee #1. Employee #1 sustained minor injuries and was taken to the University of California, Los Angeles Medical Center Emergency Room in Los Angeles, California. Employee #1 was examined, treated and released the same day. The causal factor of the accident was that the vertical face of the excavation behind the retaining wall was not shored or sloped properly to prevent a cave-in.