When you look at a map of the existing pipeline crossing the Ogallala Aquifer, you realize what nonsense that fear is:
http://www.transcanada.com/docs/Key_Projects/Ogallala_Aquifer_Map.pdf
I lived for thirty years with a pipeline running through my front yard. Other than the time that I came within a few feet from uncovering the pipeline while bulldozing a driveway, I never even considered that it was there. My family and I slept soundly, knowing that much needed energy was flowing beneath our land.