Municipalities are discovering rapid degradation of infrastructures in wastewater collection and treatment facilities due to infiltration of leaking water from the surrounding environments. Rehabilitation of these facilities by in situ methods, including the use of grouting, is used to return structures to their original working conditions. Grouting is the most widely used leak-control method in small to large wastewater treatment plants and other collection systems. Application of grouts to leaking joints is considered a challenge, and performance must be evaluated using model tests representing close to actual field conditions. The grout used for repairs must be durable enough to withstand the effect of the severe physical and chemical environmental conditions to which it will be subjected to during the service life. This verification evaluated Separation Systems Consultants, Inc's (SSCIs) supplied GST Number 3 grout under laboratory conditions at the Center for Innovative Grouting Materials and Technology (CIGMAT) Laboratories at the University of Houston. Testing was conducted on the grout and a grouted substrate over a period of 6 months to evaluate the grouts performance under various simulated physical and chemical environments.