Northern Border Partners, L.P.. The Group's principal activity is to transport natural gas imported from Canada to the United States. The Group's operations are comprised of three segments. The Interstate Pipelines segment provides natural gas transmission services in the midwestern United States. The Group owns a 1,249-mile interstate pipeline system that transports natural gas from the Montana-Saskatchewan border to interconnecting pipelines in the upper Midwest of the United States. The Natural Gas Gathering and Processing segment provides services for the gathering, treating, processing and compression of natural gas and the fractionation of natural gas liquids for third parties and related field services. The Coal Slurry pipeline transports crushed coal suspended in water. Natural gas transportation accounted for 68% of 2002 revenues; Gas gathering, 27% and Coal slurry, 5%.