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Louisville Fluoride Tank Coating Case (SES)

A secondary containment area for the Louisville Water Department needed remedial work. The water is a fluoride solution destined for addition to drinking water supplies, but the project area was strictly for spillage protection from not only potential run off into adjacent ground water but also because of the proximity to the front of the building which has offices.

Problems
Time, distance, and vertical surfaces, and close proximity to workers.
The window for completion of the work was only 30 days. Conventional coatings are typically two-part epoxy solutions which require about 24 hours to cure between coats and such a project would take a minimum of one to two weeks, including preparation time.

There was also a requirement for an NSF61 potable water certification for the coatings which also narrowed the field of suitable products. The vertical surfaces on sides and legs of the inserted primary fiberglass tank, would need to set up in seconds if thinning and dribbling was not to be a problem. There were also some damp patches of concrete where moisture had seeped through.

Solution
Southern Epoxy Solutions concluded that ECODUR 201S would provide a much more durable and simpler solution. Not only does it set up in a few seconds for effective vertical surface use, it also fills in cracks quickly and deeply, retaining long term flexibility should a surface move over time as a result of structural shift or temperature variations. It also went on in one coat.

Overall start to finish time was one and a half days, roughly equally divided between preparation and application, and touch ups.

Application results
One major benefit that was apparent even from the start was that odor was negligible as ECODUR 201S is entirely free of any volatile organic compounds VOCs, either in their content, application, or clean-up of the spray gear. The Water Department staff commented that they greatly appreciated not smelling strong vapors as their main entry point into the building was only 25 feet away.

The application of ECODUR 201S was, predictably, considerably faster than a conventional epoxy. It also provided better coverage of damp spots and subsequent pinhole treatment. With epoxy coatings, touch up require very lengthy waits until an applicator can back to the target sites. Southern Epoxy Solutions reported they only waited 30 minutes for any touch ups.

They also reported that with ECODUR 201S bonding so readily to itself, they felt much more confident about the long term patching ability as compared to conventional epoxies.
Vertical surfaces were satisfactorily coated in one pass in the concrete secondary containment structure as were the fiberglass legs which supported the primary containment tank.