Well, that explains the lower pump current you reported in post #53.
I'm surrounded by 5 major earthquake faults and see unusual changes in water flow occasionally. A while back the river out front of my home lost half of its flow in 30 minutes. Within a couple of days we experienced a series of low level quakes (2's, 3's, etc.) and then the river returned to normal flow.
Without sounding like too much of a geek, I view your situation as a golden opportunity for a little science experiment. Record your ground water level and water temperature and plot it over time. If you don't have a convenient way to obtain water level, substitute pump pressure for that number.
Also record the earthquake info for your area. Don't depend on your "butt" to tell you when there's been an earthquake, go to this USGS site: Maps of Recent Earthquake Activity in California-Nevada. Their maps are updated real-time. Mark this info on your plot of water table level and temperature. I suspect you'll start to see a correlation between the data sets.
Would I worry? Hell no! Well at least not based on the info you provided so far, anyway.
Have fun with it! You're lucky to be part of this once in a lifetime opportunity!
--Boot Hill