Need some insight into my sump pump.

Just a background on the location of my home. I live relatively close to Standly lake.

My sump pump has been kicking on every few days. I know before the well used to be bone dry. Does any one know why water would be seeping into my well? The water is also crystal clear. I also have a concern will the pump sucking up the sand at the bottom of the well, can someone help me out on this one?

Thanks

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