While North America has been gripped by controversy over the Keystone XL pipeline that would ship crude to the United States from the Canadian oil sands, a small Canadian company has been quietly digging in the oil sands of Utah with a secret weapon it thinks may end the environmental argument: citrus. U.S. Oil Sands Inc says its method will cut the cost and reduce the energy needed to separate oil from sand, lowering the environmental impact. Opponents are far from convinced. The Calgary-based firm is developing its PR Spring project on a 32,000-acre lease about 280 kilometers (174 miles) southeast of Salt Lake City. It plans to start producing 2,000 barrels per day next year with the potential to reach 10,000 barrels per day. Its patented technology uses a solvent whose main ingredient is derived from orange and lemon peels. […]