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At approximately 4:30 p.m. on February 23, 2000, employees were working on a "French-drain" pipe at a wastewater treatment plant. The slopes of the north and south banks, above the trench shield, ranged from 61 to 88 degrees. Prior to the project bidding, the city had hired a local civil engineering firm to conduct geotechnical testing and report on subsurface soil conditions. One of the soil borings, Boring #2, mentioned in the report was located approximately 28 ft west of the well-point location. Boring #2 showed layers of medium stiff to very stiff tan and gray clays, down to a depth of 12 ft over a layer of dense tan fine sand, down to its final depth of approximately 20 ft, (i.e., "Type A" soil over "Type C" soil). The geotechnical report clearly identifies the need for "dewatering device(s)" between 9.5 ft and 19 ft at this facility location to remove ground water (year round). This report states three times that any excavations should be made in accordance with OSHA requirements for "Type B Soil". The report also mentions the presence of substratum sands, and the need to verify soil classifications during construction in the field. Employee #1 had gone into the 19.5-ft deep excavation to locate the west end of the 15-ft-to-20-ft-long pipe. The Job Superintendent overseeing this work said the crew had moved the 20-ft-long by 4-ft-wide by 8-ft-tall GME Trench Shield toward the west and away from an operating, vertical 12-in.-diameter well-point pipe about an hour earlier. The excavation measured 59 ft long, east to west, and was 12.8 ft to 19.9 ft wide. The excavation's north wall collapsed, killing Employee #1.
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