United States Environmental Protection Agency Region 5 award winning facility for excellence in Operation and Maintenance; this is a direct reflection of the Ionia Waste Water Treatment Plant staff’s commitment to excellence. The Ionia plant was designed to treat an average flow of 4 million gallons per day serving a population of over 10,500 located within the city of Ionia and the townships of Berlin, Ionia, Orange and Easton. Two of the plants digesters, number 3 and 4 have concrete domes that span more than 40 feet in diameter with gas draw off systems located on the top, with more than 3,500 square feet in surface area. The two domes were constructed at different times with different coating and insulation systems. Digester 3 utilized a dry –pack build up for the insulation with a traffic coating topping, while digester 4 had 2 inches of spray foam with an asphaltic based roof coating. The engineers determined that the efficiency of the added insulation did not offset the long term life cycle costing of the domes, specifying a urethane traffic coating system.
The condition of the concrete along with the differences in the insulation and coating systems posed unique challenges; individual removal and surface preparation plans were required. In addition to the presence of methane gas inside of the digesters, venting out at the top of the domes called for a job specific safety plan. Dangers of static build up and spark emitting removal procedures had to carefully be factored in during the removal process. The presence of methane gas required constant monitoring of the methane levels in conjunction with a gas ventilation system to ensure a safe work environment. Other procedures such as hydro blasting of the concrete was approve and utilized to eliminate the potential of static build up. Once the insulation and coatings were removed and the concrete was repaired and prepped, a solvent based polyurethane multi coat system was installed. The end result is a durable coatings system that not only looks good but will add years of durable protection.