The Structure of the Ogallala Aquifer & the TransCanda Pipeline

Only on 10/11 Governor Dave Heineman explained live why he wants the proposed TransCanada oil pipeline re-routed. He doesn't want the state's main water supply contaminated. We looked into what makes up the Ogallala aquifer.

One UNL professor released a study that says an oil spill could be a catastrophe for the aquifer.

But another emeritus professor says a spill couldn't possibly threaten the entire aquifer.

The stakes are enormous with more than 70 trillion gallons underneath Nebraska.

The Ogallala aquifer is not a lake, but sand and concrete sediment built up over millions of years.

UNL Emeritus Geologist Professor Bob Diffendal says, "There's tremendous variability from one place to another. In some places it's so well cemented water will not move through it."

Diffendal's studied the geology of the aquifer for more than 20 years and taken drill samples to find out the structure of the aquifer.

He tells 10/11, "When you get down below the water table, the aquifer, that's the part that's water saturated is in between the individual grains of sand and gravel."

The Ogallala aquifer lies underneath eight states and covers 174,000 square miles.

66 percent of the water in the Ogallala aquifer is in Nebraska. Hydrogeologist Jim Goeke says the water moves west to east very slowly downward at right angles.

Knowing that, Goeke says when it comes to the proposed TransCanada pipeline, the entire aquifer would not be at risk.

He tells 10/11, "Hydrologically it's impossible, with 75% of the aquifer is west and up gradient."

Meaning if there were a leak in the pipeline, contaminated water can't travel upstream.

Goeke says, "So that puts everything west of the pipeline out of play."

And Goeke adds if there were a contamination, the structure, water flow and make-up of the aquifer would keep it very localized.

"It would probably be within a mile or two of the pipeline, of the right of way, so it's going to be very localized if there's a spill."

On the other hand, a study done by another UNL professor, Dr. John Stansbury, on the consequences of worst case spills from the pipeline says 4.9 billion gallons of water in the Sandhills would be contaminated.

A quote from his study published online says, "Could form a plume 40 feet thick, by 500 feet wide, by 15 miles long." He also says, "It would pose serious health risks to people using that ground water for drinking and irrigation."

10/11 did try contacting Dr. Stansbury, but he did not get back to us.

Jim Goeke says the study which predicts a plume that's 40 feet thick, 500 feet wide and 15 miles long, ignores the composition of the aquifer.

He says, it assumed the aquifer was all one uniform material and could move easily in every direction.