HollyFrontier Corporation is an independent petroleum refiner that produces refined products, such as gasoline, diesel fuel, jet fuel, lubricant products, and specialty and modified asphalt. The Company operates in two segments, including Refining operations and Holly Energy Partners, L.P. (HEP). The Refining segment includes the operations of its El Dorado, Tulsa, Navajo, Cheyenne and Woods Cross Refineries and NK Asphalt. The HEP segment involves all of the operations of HEP. The Company�s refineries are located in El Dorado, Kansas (the El Dorado Refinery), Tulsa, Oklahoma (the Tulsa Refineries), which consists of two production facilities, the Tulsa West and East facilities, a petroleum refinery in Artesia, New Mexico, which operates in conjunction with crude, vacuum distillation and other facilities situated 65 miles away in Lovington, New Mexico (the Navajo Refinery), Cheyenne, Wyoming (the Cheyenne Refinery) and Woods Cross, Utah (the Woods Cross Refinery).