An employee descends the stairwell after conducting a safety inspection of a chimney at the Vostok Energo power plant, operated by the Donbass Fuel &amp; Energy Co., or DTEK, in Donetsk, Ukraine, on Thursday, Oct. 18, 2012. DTEK, Ukraine's largest private coal and energy producer, signed a supply contract with OAO OGK-2, the Russian wholesale power generator controlled by OAO Gazprom. Photographer: Vincent Mundy/Bloomberg via Getty Images