One of the things to complete the quest is to talk twice with Sully Mathis. Starting the quest, and ending it, but after you talk with him for the last time, and end the quest, "Talk to Sully Mathis" doesnt get marked as done.

Same here. Wasn't sure if this was a bug or what. Sully said he'd need some more time to tinker with the pump, but I've waited 5-7 in-game days and the quarry is still filled with water.

Same here.

Im having this problem too.