Government documents allegedly show the New South Wales environment department had picked a side on the coal train dust issue, before seeing the results of a report it commissioned.

The Hunter Community Environment Centre says it has thousands of documents obtained under freedom of information, which show the Environmental Protection Authority (EPA) knew of the significant pollution caused by un-covered coal trains.

The Environment Centre says it also has a copy of a draft press release stating there was no risk, written before the actual results had been viewed.

Environmentalist and spokesperson for the Hunter Community Environment Centre, Dr Jame Whelan, says it is evidence of a cover-up.

“The EPA has been more concerned with public relations and spin than they have been with finding out problems with the environment and putting in place measures to control that pollution,” he says.

“We know that the EPA locked themselves into a position that coal trains were not a source of pollution before they even received the report.”

“Five hundred people in Newcastle have already written to the Premier calling for an Upper House parliamentary inquiry into this matter.

“When the head of a government department and an Environment Minister mislead the community in this way and mislead Parliament, an inquiry is necessary to uncover how we've been misled so systematically,” Dr Whelan said.

Chair of the New South Wales Environment Protection Authority Barry Buffier says it is normal procedure to produce a range of statements, and not publishing it meant it was not the EPA’s official stance.

“We were at the time under a very tight time frame in terms of getting the report out so within media someone may have drafted a document trying to be ready for when the report was put out,” he told the ABC.

“The draft media release, is merely that, a draft media release.

“The proof that we are not trying to hide anything here really lies in the fact that I commissioned an external, independent peer review of this process because I knew it was an issue of concern in the Hunter,” he said.

“If I was trying to hide something, if I was concerned about issues like that, I would not have gone to an external peer review, would I?”