The water line should be PVC, which will not allow the product to penetrate into the water line. Also, if the line is 12” deep and you dig down 6” deep, then you should be fine as far as not hitting the water line.
Dominion 2L Termiticide is applied at 0.1 to 0.2 fl oz per inch of trunk diameter for trees at the base of the tree inside the drip line. For a tree measuring 187” in diameter, the rate of Dominion 2L needed would would come to 18.7 to 37.4 fl oz for soil drenching. The minimum amount of water recommended for trees is 16 oz of water per inch of trunk diameter but can use more if needed. Based on the product label recommendation of 16 oz of water per inch of trunk diameter for trees, a minimum of 23 gallons of water would be needed. Keep in mind, water simply acts as a carrier and it is important that even distribution of the product is achieved.
After the soil drench has been applied you should water it in with at east 1/2 inch of water. Before applying drenches, it is important to remove or pull back any mulch or dead leaves so the insecticide solution is poured directly on the mineral soil. It is also important to keep the soil around the tree or shrub moist for the next 7-10 days after applications to encourage uptake.
Please review the product label for more information.
Dominion 2L Termiticide Concentrate cannot be used inside so is not labeled for bedbugs nor is it labeled for common crickets. It can be used as a perimeter spray outside around the foundation for ants and roaches or as a systemic soil drench on plants/trees for aphids. You can review the product label for the list of insects it controls and application instructions.