Ekibastuz (ĕkēbästŏsˈ) [key], city (1990 pop. 134,627), N Kazakhstan. It is the industrial center of a bituminous coal-mining basin, which has coal reserves estimated at 8 billion tons. Although coal mining began in the late 19th cent., the city became industrialized only in the 1950s, when the railroad reached it. The coal is burned to provide electricity.