Summary:
About 8:00 am 02/03/03 ***** personal began to set up the 50-ton rough terrain crane at the oil barge dock to unload cargo for the ***** project. After the crane was positioned approximately 8′ from the edge of the bulkhead and all pre-lift checks had been made with dry run we proceeded to lift the first piece. The operator lifted up the cargo about 10 to 12 inches high and stopped to insure the load and crane was stabile, at that point the operator felt a shift in the crane and felt the concrete on his left front outrigger cave in. The load came back to rest in its original position on the barge. No one was hurt due to this incident minimal damage done to property.
Root Cause:
the soil was undermined beneath the concrete where the outrigger was set to stable the rig for lift.
Contributing factors:
From past experiences of ******** employees and boilermakers present at the time of the incident, that area had not been a problem location. Heavy equipment had been placed there and used in the past to unload barges with no incident prior to this date.
Corrective action:
******** had the soil tested on 02/03/03 to determine if the undermining was isolated and insure soil stability for future location of equipment as well ******** will have better communication with ******** for other locations that may have possible known undermining prior to setting up equipment in the barge area. ******** has repaired and compacted the undermined area.
Submitted by Casper, our friendly Safety Professional
