Prime Resins, Inc.
2291 Plunkett Road
Conyers, GA 30012

May 6, 2004

This letter is to provide validation of the durability of the chemical grout products we supply. With proper installation per the instructions, our chemical grout used to stop leaks or to stabilize soil can be expected to surpass even the lifespan of the structure it has been applied to. As for a definition of the lifespan of concrete, for example, the May 3, 2004 issue of ENR (Engineering News-Report) supplied a good explanation in a side-column feature called “Concrete Q and A’s”.

“How long is it reasonable to expect a concrete structure to last? Time itself has no effect on concrete. The material sets, hardens, gains strength and exhibits reduced permeability over time. But the changes result from an interaction with the surrounding environment, not merely the passage of time. For example, a very cold or very dry environment will greatly retard and alter the process of change that occurs naturally in a warm, moist environment. Concrete needs to be formulated to survive the unique demands of the particular service condition in which it is located to survive.”

 Prime Resins polyurethane chemical grouts and gels are formulated to last beyond the life of the structure. They are also inert when cured and are non-toxic. When applied correctly and for the proper application, they do not break down. In fact, in July 1999, Rehabilitation Technology magazine published an article that explained that chemical grouting for rehab should be considered “a permanent repair”.

“Rick Harris, sewer maintenance supervisor for the Borough of Downingtown, PA, has over 20 years of experience with chemical grout. The first half of those years was spent as a grout contractor while the last half has been spent in his current job. “Chemical grout is definitely the most cost- effective way to stop groundwater infiltration into a sewer system,” he said….

…As Harris said, “I don’t know where the idea that chemical grout is just a Band-Aid came from because there are millions of joints sealed with grout that are still dry after more than 20 year.

We also have a longevity report from NASSCO with project specific data compiled to track the
durability of chemical grout (see case studies).

Prime Resins

Julie Merced

Corporate Technical Services Structural Engineer
ASTM Testing – Research & Development