What is the Ogallala Aquifer?

The Ogallala or High Plains Aquifer underlies an area from South Dakota to Texas and is a significant source of water for drinking and irrigation. It is one of many treasured sources of water in the United States. Independent government analysis has concluded that a pipeline leak would not threaten the aquifer. Here are seven facts to help explain how this finding is consistent with the nature of the aquifer and other aspects of daily life.

Today, nearly 25,000 miles of petroleum pipelines exist within the Ogallala Aquifer, including 2,000 miles in Nebraska. These pipelines transport about 730,000,000,000 barrels of crude oil across the aquifer – each year, including nearly 100,000,000 barrels of crude oil transported across the aquifer in Nebraska. After this oil is refined into gasoline, diesel fuel, aviation gas and other products, pipelines transport much of it back across the aquifer for use on Nebraska farms, ranches and roads.

The Ogallala Aquifer — part of the High Plains Aquifer System — consists of braided layers of sand, gravel silts and clays deposited over the millennia. Water flows through the small “interstitial” spaces. Although it’s easy to think of the aquifer as an underground lake in a cavern across the surface of which oil might easily travel, that is not its nature. As shown in the photo at right, the makeup of the aquifer actually resembles a mechanical filter. Like dirt and other particles, oil has a very difficult time moving through this physical environment. Even the water itself moves very slowly — about one foot per day, according to USGS. Some hydrocarbon contaminants can dissolve in the water but that takes time and then movement is very slow and limited in extent. Even if there were a significant release from the pipeline in an area where the oil could reach groundwater, movement of hydrocarbon contaminants in groundwater would be neither broad nor regional.

Since 1930, 24,000,000,000 barrels of crude oil have been produced within the Ogallala Aquifer. In Nebraska, 500,000,000 barrels of crude oil have been produced from 2,000 oil wells drilled through the Ogallala Aquifer.

In response to input from Nebraskans, the safety of the aquifer was independently evaluated in detail in the Environmental Impact Statement (EIS) prepared for the U.S. Department of State as a part of the multi-agency regulatory review of the project, now entering its third year. The EIS includes detailed information on a major oil release in 1979 of 10,700 barrels, in sandy soils with shallow groundwater, similar to the environment in the Sandhills of Nebraska. The groundwater impacts are limited to within 650 feet from spill, and only in the direction of underground water flow. Details of this analysis are available on page 3.13-55 of the EIS. The discussion forms part of a broader, 100-page analysis of what would and what could happen in the event of an oil release from the pipeline in Section 3.13. The full document is available online at www.keystonepipeline-xl.state.gov.

The conclusions of the independent regulatory review are consistent with preeminent Ogallala hydrologist and UNL Professor Emeritus Jim Goeke’s testimony before the Natural Resources Committee that if groundwater were affected, he expected the impact would be measured in the tens of feet or hundreds of feet. It is also consistent with experience from other historical oil releases affecting groundwater, which demonstrate that movement of dissolved hydrocarbon constituents typically is confined to less than 300 feet.

This is why regional petroleum contamination of the Ogallala Aquifer has not been a problem despite:

• The decades that crude oil has been withdrawn through the Ogallala Aquifer in western Nebraska and in other states;

• The decades that petroleum has been used to lubricate and power farm equipment on farms across the state;

• The decades that oil has been applied for dust control on rural roads throughout the state.

The existing petroleum pipelines that cross the aquifer are required to meet federal safety standards that will also apply to Keystone. In response to concerns about safety in Nebraska, Keystone has also voluntarily committed to be bound by a new chapter of federal pipeline regulation. When petroleum pipelines must cross wellhead protection areas or highly populated areas, additional safety measures are required to help ensure the protection of critical resources or large groups of people. Keystone has adopted these provisions throughout the entire Sandhills and Ogallala Aquifer areas and throughout the entire pipeline.  Keystone has also adopted additional safety measures that even pipelines crossing sensitive settings have never had to meet. Together, these provisions require stronger steel, better fabrication, more protections against pipeline failure, repeated testing to ensure integrity, greater vigilance to detect abnormalities, and the most highly-trained construction and operations work forces ever.

Keystone will be bound by existing Nebraska law confirming that it is responsible to clean-up and is financially liable for oil spills, road repairs, and damage done to land or contamination of water supplies. (See Neb. Rev. Stat. §§ 76-3301 to 76-3306 and §§ 81-1501 et seq.; See 29 Neb. Admin. Code Title 126, Part 18.)