Completed in March 2021, the Mt. Comfort Lift Station is the most recent upgrade and expansion of the Mt. Comfort Corridor development plan for Central Indiana. Penetron’s innovative anti-microbial concrete admixture, protects key lift station concrete elements from microbially-induced corrosion (MIC). PENETRON ADMIX SB was used to waterproof the project’s precast concrete manhole structures.
The towns of Cumberland, McCordsville and New Palestine, are located in central Indiana and make up the Mt. Comfort Corridor. This region is not only a well-traveled traffic conduit to downtown Indianapolis via 1-70, but also comprises the fastest growing communities in the state. The three municipal governments have collaborated on a comprehensive regional development plan that also encompasses expansion of the shared wastewater treatment infrastructure.
“The Mt. Comfort Corridor collaboration has implemented a number of notable upgrades to the sewage and water treatment infrastructure of the three communities,” adds Christopher Chen, Director of The Penetron Group. “These include a multimillion-dollar wastewater treatment plant expansion and further lift station improvements. The Mt. Comfort Lift Station is a central part of the most recent phase of upgrades.”
Seeking Protection from MIC
The Mt. Comfort Lift Station project comprised construction of a number of manholes as well as a wet well lift station (measuring 33’ x 96”). The project’s precast concrete supplier asked Penetron for a solution to provide protection against microbially-induced corrosion (MIC) within the lift station’s wet well.
Micro-organisms within these sewer environments are responsible for converting hydrogen sulfide gas (H2S) into biogenic sulfuric acid (H2SO4). The formation of biogenic sulfuric acid on the surface of the concrete causes the concrete to deteriorate and metal embeds to corrode causing further damage to the concrete, a process known as MIC. Added to the concrete mix during batching, Penetron’s anti-microbial admixture uses an electro-physical mechanism to destroy the cell walls of micro-organisms on contact and thus prevent the production of biogenic sulfuric acid and the damaging effects they cause.
“Penetron’s anti-microbial admixture becomes an integral part of the concrete matrix and is completely leach resistant,” adds Christopher Chen. “This anti-microbial admixture is just as effective years later as it is on the first day – regardless of repeated contact with the micro-organisms – to ensure permanent MIC protection for the concrete matrix.”
Crystalline Formation Prevents Leaks
PENETRON ADMIX SB was also added to the concrete mix as a waterproofing solution for the precast manhole structures. When added to the concrete mix, the proprietary chemicals in PENETRON ADMIX SB react in a catalytic reaction with moisture to generate a non-soluble crystalline formation throughout the pores and capillary tracts of the precast concrete element. The resulting crystalline formation seals pores and micro-cracks, and becomes an integral part of the matrix, making the concrete impermeable. The concrete also has the ability to self-heal newly formed hairline cracks, significantly reducing the maintenance needed over the lifespan of the concrete manhole elements.
“Both PENETRON ADMIX SB and our new anti-microbial admixture will continue to provide the needed durability to the concrete and significantly reduce any future maintenance of the treated concrete structures,” concludes Christopher Chen.
