Sakhalin Energy stated that it spent about US $19 million on the upgrade works .
ExxonMobil and Sakhalin Energy , oil and gas companies working on projects in the region , had upgraded the airport .
companies   stated that Sakhalin Energy spent about US $19 million on the upgrade works .
ExxonMobil and Sakhalin Energy , oil and gas companies working on projects in the region , had upgraded the airport .