An employee had been spotting for a mini-excavator. The employee was working to relocate a water pump to give the mini-excavator an adequate area for the spoil pile. The employee retrieved the water pump located beside a 24'' metal manhole cover. As he started walking, his right foot stepped on the edge of the manhole cover and his right leg went into the opening up to his knee. His left leg and foot remained on the ground and twisted as he lost balance and fell to the ground. The employee sustained a closed dislocation of the metatarsophalangeal joint of the left foot and required surgery.