If you want to heat and light the pump house, pull 2] 10g for the pump and 3] 12g of the correct colors. Install a small sub panel and a ground rod would not hurt, although you have your ground in the green or bare wire of the 12g portion of the run. 3/4" pvc conduit.

Remember to make your pro read the AIM manual.

Lots of rules on telephone and electric seperation and sewer and water seperation, but not many on electric and water. I have rarely opened buried conduit that was not full of water anyway. Moral of story, be careful pulling wire not to damage insulation.