1) I have 4 pipes that come out of the ground. One goes into the pump. Two come out of the filter. The third one just sits there 4 feet out of the ground and connects to nothing. It has a threaded cover at the end. I don't know what this pipe is or if there is anything I should do with it. Should I take off it's cover?


More than likely, it is a pressure side vac line that was removed when the system was re-plumbed.