We have a seasonal well and like clockwork, during this August's dry season, the well water replacement rate is below that of household use.
1. There is a considerable amount of limestone in the area, so a cave is not an unreasonable hypothesis.
2. We do have hard water coming from the well
3. We have a Well Manager for conservative water draw (20 sec/hr) is usually enough to replace normal household use (3 adults).
4. We have had (one time) the Water Wagon come and add water to the well to help it recover during the dry season.
Last Election Day, the water wagon came to fill our well manager tank (~200 gal) four 55 gal barrels and to fill the well (100 ft/6" casing).
The minimum delivery from the water wagon was 2000 gallons. After filling the tanks in the garage, the driver put approximately ~1500 gallons into the well. The water going in got to the top and then rapidly disappeared down the column. (well recovered after the addition of water and we are now just getting to the 55 gal barrels to alleviate our current water shortage)
My question: before I ask the Water Wagon to come fill the well again, am I creating a geologic disaster like a sinkhole or am I just more likely filling some vein that is leading to some unknown deep cave somewhere or is there no way to know without a full sonar/geologic survey? I just do not want to be responsible for some disaster. I may be paranoid or just cautious?
If the well was sealed off, a 100' deep well will only hold about 150 gallons of water. You are just pouring water into a crack in a rock and it will probably go somewhere else. A larger cistern for the Well Manager would be better. A 1500 gallons storage tank is sealed and the water can't leak out and go away. Your well might even be able to keep up if you have a larger cistern tank. If nothing else, the water from Water Wagon would not just be wasted pouring it down a hole in the ground.