TOURISM operators have launched the third legal action against the Abbot Point dredging project, taking on the Great Barrier Reef Marine Park Authority over the approval.
The action, launched by the Association of Marine Park Tourism Operators, is the third separate legal action against various aspects of the project's approval.
It follows two other separate challenges by environmental groups to both the authority and Environment Minister Greg Hunt's approvals of the project.
AMPTO executive director Col McKenzie said the association's court case centred on challenging whether the authority adhered to its own legislation.
He said the case questioned whether the authority took account of the "precautionary principle" in approving the development.
"We believe the decision is not in accordance with their legislation, there can be no doubt that the science is not firm," he said.
"There is an enormous amount of doubt, and based on that, the authority has not adhered to the principle."
"Simply, I think some of the senior management team decided to mirror the minister's decisions because that's what they felt the minister wanted."
Mr McKenzie said so many scientists had raised doubts about the effect of the dumping that the authority should not have approved it.
"They could have ordered that a longer jetty be built, it's a fairly costly exercise, or they could have said they had to dispose of the spoil on land," he said.
Mr McKenzie said the court case represented the "business end of town" that could be affected by the approval to dump three million cubic metres of dredge spoil in the marine park.
"We're not against mining, not against dredging or port development or exporting coal, but we are a business group and we want to have a pristine environment to offer tourists," he said.
"This could take 18 months or two years to resolve, but we had a really good look at our options a month ago and decided we would challenge the authority's approval, certainly it's not going to happen overnight."
A spokeswoman for the marine park authority said it could not comment as it was now before the courts.
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