A Queensland tourism group is mounting a legal bid to overturn a decision to allow dredge spoil to be dumped in the Great Barrier Reef Marine Park.

The Great Barrier Reef Marine Park Authority (GBRMPA) gave developers of the Abbot Point coal port, near Bowen, the green light this year to dump three million tonnes of spoil offshore.

The Association of Marine Park Tourism Operators (AMPTO) claims this decision breaches the authority's own legislation to protect the reef from potential harm.

"We want the decision overturned," AMPTO spokesman Col McKenzie told AAP on Monday.

"The reality is that there is more than enough scientific opinion out there to say that this will do irreparable damage to the reef.

"There is a very clear requirement in the GBRMPA act for them not to grant a permit to do an activity where there is doubt to the affect it will have on the reef."

Mr McKenzie, who claims he isn't against the Abbot Point expansion and isn't anti-development, says his group wants the spoil dumped onshore.

Next month, the group plans to take GBRMPA and developers North Queensland Bulk Ports to the Federal Court to challenge the decision.

Queensland Resources Council chief executive Michael Roche says claims about a lack of scientific scrutiny surrounding dredging didn't stack up and studies specific to Abbot Point were readily available.

"Not one of these studies - including on dredge plume modelling and water quality - has been questioned in terms of their scientific validity," he said.

The federal government and GBRMPA are allowing Bulk Ports to dump dredge spoil in the park as it turns the Abbot Point port into one of the world's biggest coal terminals.

The spoil will be dumped about 40 kilometres from the nearest offshore reef, but green groups claim it will harm coral and other marine life.

A number of other environmental groups have also mounted legal challenges to overturn the decision.