hole near geotherm field

zepfan

i went on a call today at a house that we did not install the geotherm system,but have done all the service on it for the last five years.the system currently works fine with no operating problems.the house has five florida heat pumps installed on the loop.the whole system is eight years old.the homeowner noticed a hole in the backyard that is about five inchs in diameter in diameter and appx. 25 feet deep.it is located directly over the ground loop.i put a tape measure down through it and the whole tape measure had no signs of noticable moisture anywhere on it.the only thing i think this could be is a dry hole from where they were going to install his well.the only thing that concerns me is that it is so close to the geotherm field.all the measurements and readings that i took today do not indicated that there is a problem with the geotherm system.i was going to tell him to go ahead and back fill it and forget about it,but was wondering if anyone else has ever ran into this with a geotherm system.thanks to all.i have attached a picture of this hole.