|Semgroup Corporation provide 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, 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 United Kingdom that enable customers to supply petroleum products to markets in the Atlantic Basin. It also operates a network of liquid asphalt cement terminals throughout Mexico. The Company conducts its operations through six primary business segments: Crude, SemStream, SemLogistics, SemCAMS, SemMexico and SemGas. Effective August 1, 2013, SemGroup Corp acquired the entire interest of Mid-America Midstream Gas Services LLC, provider of gas transmission services, from Chesapeake Midstream Development LP, a wholly owned unit of Chesapeake Energy Corp.