From JPCL September/October 2024
By the summer of 2022, the coatings protecting the Village of Caseyville, Illinois’ Wastewater Treatment Plant assets had reached their performance life expectancy. The protective coatings on the critical infrastructure substrates were spent, worn and some assets were beginning to show signs of corrosion. Within the plant, assets requiring refurbishment included clarifiers, pipes and racks, stairs and catwalks, structural steel, rails and miscellaneous metals, doors and generators, as well as block and pre-cast concrete buildings. In summation, the whole facility needed a fresh coatings job.
Along with Caseyville’s hired engineering firm, the painting contractor teamed up with the coating manufacturer to specify the optimal coating solutions for each substrate, with performance, project timing and weather conditions in mind.
The surface preparation and coatings work at the facility began in September of 2022. According to the specification prepared by the engineering team, the following sequence of work was completed. The exteriors of the steel clarifier tanks were abrasive blast-cleaned to an SSPC-SP 6/NACE No. 3 Commercial finish. The contractor then applied one prime coat of a thick-film ceramic epoxy, selected to replace more costly traditional zinc primers without sacrificing performance. This coating also allows for a 45-minute time-to-recoat, a one-year maximum recoat window and low moisture vapor permeability. After primer application, an intermediate coat of a high build, surface-tolerant epoxy chosen for its adhesion properties on overcoating jobs was applied, followed by a urethane finish coat (Fig. 1).
Fig. 1: The clarifier, structural steel and catwalks were finished with a gloss urethane topcoat, colored according to safety and specific color codes for piping and mechanical identification. aLL Photos: Scott Simmons, Thouvenot, Wade & Moerchen, Inc. / Village of Caseyville
The steel catwalks, stairs, structural steel, railings, pipe, pipe supports and other miscellaneous steel received a 5,000 psi pressure wash according to SSPC WJ-4, as well as hand- and power-tool cleaning according to SSPC-SP 2 and -SP 3. The contractor then applied a prime coat of high build, surface-tolerant epoxy and two coats of urethane finish, with both offering color and gloss retention characteristics in extended UV exposure (Figs. 2-7).
Figs. 2 (above) and 3 (below): These show the condition of some of the facility’s piping systems before (left) and after (right) cleaning and coating application.
Figs. 4-7 (below): Various catwalks, stairways railing, piping and structural steel were recoated in the facility’s exterior storage area and concrete basins.
The CMU block and cast concrete structures also received a 5,000 psi pressure wash according to SSPC WJ-4, and two coats of a low-odor, water-borne acrylic epoxy formulated for toughness, stain resistance and waterproofing characteristics (Fig. 8).
Finally, the doors and facility generator received a pressure wash, a SSPC-SP 2 hand tool clean, a prime coat and two coats of an acrylic polysiloxane for durability and color retention properties (Fig. 9).
Figs. 8 (above) and 9 (below): Cementitious building surfaces and the facility generator were also coated to refurbish the facility’s previously deteriorating conditions.
All in all, this project was another example of all the parties working together toward one goal—an issue-free application that extended the service life of the treatment plant assets for the owner. The contractor credited proper product selection and technical service received from the coating manufacturer, as well as the field performance of the project superintendent, site foreman and coating applicators.
Paul Powers, Mid-Central Regional Manager
Induron Protective Coatings
Paul Powers is the Mid-Central Regional Manager for Induron Protective Coatings. He is a NACE-certified Coating Inspector (Level 3) with more than 40 years of coatings industry experience. Powers joined Induron as a sales and service representative in 2016 and has held his current position since 2022.
Kevin White, Senior Vice President
Bazan Painting Company
Kevin White is the Senior Vice President of Bazan Painting Company in St. Louis. He has almost 30 years of experience as an industrial painting contractor, previously holding superintendent, project manager and estimator positions within the company. White is a NACE-certified Coating Inspector.
Tagged categories: Features; Recoating; Wastewater Plants; Water/Wastewater
