A group of University of Minnesota students were scheduled to join other students in boarding diesel-burning buses recently for Washington, DC. There they were planning to protest the Keystone XL pipeline and the global warming impact of carbon dioxide emissions from Canadian tar sands oil.
There is actually little difference in emissions from the tar sands oil versus conventional oil, as nearly all petroleum emissions are from burning the end products like gasoline, jet fuel, diesel, etc. Those CO2 emissions are the same regardless of the crude source.
Pipelines are the safest and most economic way to transport oil and gas. There are thousands of miles of oil and gas pipelines in the US, and they operate with minimal safety problems. Some of those lines are directly above the Ogallala aquifer, which is unaffected. The new Keystone XL pipeline will continuously monitor sensors that register pressure and leak issues. Valves are spaced along the pipeline and are closed from remote centers to limit loss from leaks.
Nearly all of the transport fuel used in Minnesota is refined from Canada's tar sands heavy oil at the Flint Hills refinery in Rosemount, Minn. The Alberta Clipper pipeline from Alberta to northern Minnesota, with a spur line to the Twin Cities from Clearbrook, carries 300,000 b/d of tar sands oil to Flint Hills, the largest heavy oil refinery in the US. A pipeline from that refinery to Minneapolis-St. Paul provides all of the jet fuel for departing aircraft.
The big threat to the Ogallala is from irrigation-based single-crop farming for biofuels. Millions of tons of fertilizers, pesticides, and irrigation water are continuously dumped on the soils which drain directly above the aquifer. A study by Prof. Sangwon Suh of the University of Minnesota reported that, in Kansas and Nebraska, 500 gal of water are required to grow and process the corn for each gallon of ethanol produced. Much of that water is drawn from the Ogallala, which declines 3 ft/year in some areas. Nature replenishes the aquifer about 1 in./year.
I hope those students will also lobby for serious carbon tax and fuel conservation measures to reduce fossil-fuel consumption. That will be a tough sell as any legislator who even suggests a few cents more tax on gasoline is likely to be out of office at the next election. Less effective dreams like covering the state with wind turbines and solar panels are resonating better with voters.
Rolf E. Westgard
Osher Lifelong Learning Institute
University of Minnesota
St. Paul
