I've drilled in ground so soft, water was not needed. However when you do hit a hard spot, your bit is usually plugged up and you have to pull out the whole string to unplug the orofice. Best to use water at all times even if, just to keep the jet flowing. In time you'll figure out what works best. The mystery of drilling is, the ground seems to change on every bore, so you need to be prepared for anything.
Big Dog
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