A major energy venture on Western Australia’s Barrow Island is one step closer to reality after getting a green light from state environmental officials. Chevron, ExxonMobil, and Royal Dutch Shell propose the development of a massive liquefied natural gas field expected to generate 10 million metric tons per year (which, in non-metric terms, is “a hell of a lot”). Some estimate that the Gorgon venture, which still awaits national approval and would be Australia’s biggest-ever resources project, will cost $17 billion to build. Earlier this week, Shell struck a 20-year deal with China to buy LNG from the trio, and the companies are talking with Japanese energy officials as well. But as Chevron and its buds go forward, they now need to factor in 36 environmental conditions from state officials, ranging from carbon sequestration to turtle conservation. Operations at the field, once expected to begin in 2010, are now likely to kick off closer to 2015.