I would have used fewer LBS services but be much happier.
The work was excellent. Further study determined most of the work was unnecessary. The leak was coming from the electrical conduit to our water pump. Your system has never run and the gravel beneath the slab was clean.
The book was pretty informative. Salesman seemed to be very competent and have lots of experience. Had he looked under some shelves (or had I done so) he might have determined the real problem which was finally fixed by our well contractor last fall.