The federal government is facing a second legal challenge over its decision to allow excavated seabed to be dumped in the Great Barrier Reef marine park.



Documents will be lodged with Brisbane’s federal court on Monday to challenge the dredging and dumping project that will expand the Abbot Point port near the Queensland town of Bowen.

The Mackay Conservation Group, which is bringing the legal action, claims environment minister Greg Hunt has contravened his international obligations by allowing the expansion to proceed.

The group will argue that under the federal Environment Protection and Biodiversity Conservation Act the government is required to fully protect world heritage-listed areas.

The legal action, to be handled by lawyers at the Queensland Environmental Defenders Office, has been bolstered by a $150,000 crowdfunding campaign from activist group GetUp!. Conservationists hope the case will set a legal precedent to help protect other world heritage sites.

“This is an unprecedented case. It will be a novel challenge for the courts,” Ellen Roberts, co-ordinator of the Mackay Conservation Group, told Guardian Australia.

“We have advice that Greg Hunt has failed his obligation to protect world heritage areas. We have long had deep concerns that the dredge plumes will affect local marine ecosystems, such as sea grasses and hard and soft corals.

“There is a lot of concern about port development, from Gladstone up to Cairns. It will be interesting to see what impact this case will have on these developments.”

In December Hunt approved an expansion of Abbot Point which will see five million tonnes of sediment dredged from the seabed in order to allow ships to access the port, which will export coal from newly cut mines in central Queensland.

The Great Barrier Reef Marine Park Authority subsequently approved the dumping of the seabed material within the reef’s marine park, despite internal documents showing it held reservations about the plan.

The authority’s approval has already triggered a legal challenge by the North Queensland Conservation Council, meaning the federal government is facing two court cases over the decision.

The government has insisted the expansion plan will have a minimal, temporary impact upon the reef. However, some scientists have argued the dumped spoil will add to the pressures faced by the reef by smothering sea grasses, used as food by turtles and dugongs, and coral.

In June Unesco’s world heritage committee will decide whether to list the reef as “in danger”, a year after warning the government over the level of development alongside the huge coral biota.