Planning Minister Justin Madden released a statement late yesterday saying he was satisfied that Esso Australia's planned extension of the Longford gas conditioning plant would not be required to undergo an environmental effects statement (EES).

Green groups attacked the decision, saying the plant will emit about a million tonnes of carbon dioxide a yea, a level about five times higher than the trigger point that forces the minister to consider ordering an environmental effects statement.

But Madden said the proposed site contained "no landscape, biodiversity, cultural heritage or water body features of established environmental significance” and as it was a brownfields site, an EES would provide no additional information.

"I am satisfied that greenhouse gas emissions will be readily assessed once the proposed plant design is finalised and that the EPA (Environment Protection Authority) work approval process will provide a satisfactory means of assessing suitable means to reduce these emissions," he said.

Esso Australia, a wholly owned subsidiary of ExxonMobil pointed out that the green groups criticising the plant recognised that gas was a much better fuel source than the coal that produces most of Victoria’s electricity.