Workers test a gas drilling facility at the Kumzhinskoe Gas Field, located in the delta of Pechora River, 60 km from Narjan-Mar, a city in Russia's Arctic. In 1979, an explosion in one of the wells caused an uncontrolled gas fountain, with the condensate polluting huge areas of the tundra around, including the Pechora River. In May 25, 1981, the Soviets tried to collapse the field with an underground nuclear explosion at 1470 m depth. The explosion caused even more damage and pollution. After that the field was closed and the area marked a nature reserve. Recently, more gas was found in the area. In 2007, then-President Vladimir Putin signed a decree demarcating the area from the nature reserve so that drilling work can begin.