Anaerobic Pond Cover Removal
Mainstream Commercial Divers, Inc. was contracted by a paper mill facility in Tennessee to provide a topside crew and equipment to assist with an over-the-water removal of a cover over an anaerobic pond.
A pontoon boat was deployed into the pond and capstans were stationed on each side of the pond to pull the pontoon back and forth across the 700’ long pond. Once the pontoon was in place, divers utilized a pole saw to cut the pond cover and frame. The gasses trapped under the cover consisted of H2S and methane, which would vent as cuts were made. As a safety measure, air monitors were aboard the vessel to ensure the H2S and methane gas concentrations did not approach safe working limits and high-pressure breathing air cylinders and full-face masks were stationed on the boat in the event respiratory protection was required due to excessive concentrations of hazardous gasses. As the cut progressed across the pond, an excavator on the shoreline pulled the cover to the bank for removal.