Work included annual cleaning of up to three digester tanks per year, for a total of five years, or until 10 digester tanks had been effectively cleaned. Each digester tank is approximately 110-ft. in diameter. Then each tank was released to Pipe & Plant with sludge at an elevation 2-ft. below the manway. Sludge contents were required to be screened and dewatered for disposal at a drying bed furnished by the Wastewater plant.
Pipe & Plant developed a three-person team specifically trained to clean digester tanks. Their proficiency in working with proprietary pumping equipment and understanding of digester tank operations allowed us to finish all 10 digester tanks within the five-year time frame.