SemGroup Corp. provides gathering, transportation, storage, distribution, marketing and other midstream services primarily to independent producers, refiners of petroleum products and other market participants located in the Midwest and Rocky Mountain regions of the United States of America, Canada and the West Coast of the United Kingdom. The company also maintains and operates storage, terminal and marine facilities at Milford Haven in the U.K. that enable customers to supply petroleum products to markets in the Atlantic Basin. It operates its business through six segments: Crude, SemStream, SemLogistics, SemCAMS, SemMexico and SemGas. The Crude segment operations include crude oil transportation, storage, terminalling, gathering and marketing in Colorado, Kansas, Montana, North Dakota, Oklahoma and Texas for third party customers as well as for itself. The Crude business unit consists of three primary operations: Kansas and Oklahoma pipeline system; Cushing storage; and the White Cliffs Pipeline. The SemStream segment is engaged in the residential propane supply business through its wholly-owned subsidiary, SemStream Arizona Propane with operations in Page and Payson, Arizona and holds its interests in NGL Energy Partners LP. The SemLogistics segment owns the largest independent petroleum products storage facility in the U.K. The main activities of SemLogistics are the receipt, storage and redelivery of clean petroleum products and crude oil at the Milford Haven site. The SemCAMS own and operate four natural gas processing and gathering facilities in Alberta, Canada. The SemMexico segment provides a variety of liquid asphalt cement products and product application services to the Mexican market. The SemGas segment provides natural gas gathering and processing services. It owns and operates gathering and processing plants and assets in Kansas, Oklahoma and Texas. SemGroup was founded in February 2000 and is headquartered in Tulsa, OK.