Abstract: Employees #1 and #2 were digging a hole in an excavation in order to put in a sump pump that would remove standing water 1 to 1 1/2 feet deep. Both employees were wearing standard 12 inch rubber boots. Within one hour of working in the water, Employees #1 and #2 felt burning on their legs where their pants were wet. After two hours they complained to their foreman/site safety administrator about the burning, but no action was taken. After three hours Employees #1 and #2 could not bear the pain and told the foreman that they were going home. The foreman then told them to wash off and see the safety administrator, who took them to the hospital. They were suffering second degree burns on the calves of both their legs. The excavation site had been used as a dump site 30 years ago by a manufacturer of acetylene and later monitoring showed a presence of calcium hydroxide in the water.