The Keystone XL extension was proposed in 2008. It is 1,179-mile (1,897 km), 36-inch-diameter crude oil pipeline beginning in Hardisty, Alberta, and extending south to Steele City, Neb. “XL” stands for “eXport Limited”, this pipeline is a critical infrastructure project for the energy security of the United States and for strengthening the American economy. Along with transporting crude oil from Canada, the Keystone XL Pipeline will also support the significant growth of crude oil production in the United States by allowing American oil producers more access to the large refining markets found in the American Midwest and along the U.S. Gulf Coast.
Pros:
1- Building modern infrastructure creates jobs and stimulates the U.S. economy.
2- Taxes paid by TransCanada provide counties much-needed revenue to pay for infrastructure.
3- Supports U.S. manufacturing.
4- Keystone XL Pipeline enhances energy security.
5- Keystone XL supports energy independence.
Cons:
1- Dirty tar sands oil
2- Water waste and pollution
3- Forest Destruction
4- Indigenous populations
5- Pipeline spills
References:
http://keystone-xl.com/?gclid=CjwKEAiAkpCkBRCtstKQo5ia5nESJACsCikRqI9M1hy4NVZ_KeE0yCpVQTu9_4_zi3HbhGuadai7YxoC_afw_wcB#sthash.Y8cLsMhI.dpuf
http://www.mlive.com/opinion/kalamazoo/index.ssf/2014/05/julie_mack_weighing_the_pros_a.html
http://harvardmagazine.com/2013/11/the-keystone-xl-pipeline