Concrete block home foundation question
I have a home over a crawl space (encapsulated) with hollow foundation blocks. I have just found out I have termites on one load bearing wall. Exterior of this wall has an at-grade wooden deck that is flush with the siding, so a termite company wants to go into the crawl space and drill holes in the blocks so it can insert tubes so a liquid termiticide can be injected into the impacted surrounding outside soil. The company says it will "fill up" the holes with the application is completed. They also intend to use the standard bait/poison stations around the perimeter of the house. My question, and concern, is will drilling holes in the blocks of the foundation compromise the integrity of the blocks, and thus the foundation. Can anyone advise me about this?