If the footer is right below the dirt level, within 6 inches, and it comes out 12 inches, then you should make your trench out where the footer ends. In other words, instead of digging a 6 inch trench directly against the structure, you will move the trench away from the house where you can dig down past the footer. You should still treat the soil in between the trench and the house (where the soil sits on top of the footer) by just drenching the soil if you can.
Termidor SC is an excellent professional termite control product for killing termites and protecting your home from future infestations. Termidor will protect your home and eliminate almost any termite problem in less than 90 days. In addition, when used as an in-ground barrier treatment, Termidor will protect your home or business for over 10 years. Termidor is completely undetectable by termites and once termites touch it they contact, ingest and spread the termiticide until it eliminates the entire colony. Termidor controls all types of termites including subterranean, formosan, and drywood termites.
Termidor SC is not a good option for fire ant control because it can only be used on or immediately next to a structure. It is not labeled to be used in the lawn.
Talstar P (Talstar One) would be a good option for chiggers in the lawn. This can be broadcast across the yard.
For fire ants, we would recommend a bait, Extinguish Plus Fire Ant Bait. This can be broadcast across the lawn or applied to individual mounds.