Environment minister Greg Hunt is set to grant himself retrospective legal immunity against potential claims that he failed to consider environmental advice before approving key mining projects.



A Senate inquiry has cleared the way for a bill to pass the upper house preventing legal challenges to environmental approvals issued by Hunt before 31 December last year, on the grounds the minister ignored expert advice on risks to threatened species.



Decisions granted immunity include controversial approvals in Queensland of dredging at Abbot Point, an LNG export facility at Curtis Island and a coalmine in the Galilee Basin.



In June 2013, the federal court overturned an approval by the then environment minister Tony Burke of an iron ore mine in Tasmania’s Tarkine forest.



The court ruled that Burke had failed to give regard to “approved conservation advice” about the impact of the mine on the forest’s threatened Tasmanian devil population, bringing work on the mine to a brief but expensive halt.



The Environment Department said the substance of threats to the Tasmanian devil was covered in its briefings to Burke, even if the official conservation advice did not pass his desk.



Hunt told the lower house the bill was necessary to provide certainty for the mining industry, facing numerous legal appeals by environmentalists against previously approved projects.



“There could potentially be more [approvals overturned] based on technicalities. These could cause endless delay without there being any substantive basis for the claims of improper decision making,” he said.



But the Law Council of Australia said there were no “clear and compelling reasons” for the bill to grant retrospective legal immunity, and that it “casts doubt on the integrity” of the way environmental protections are implemented.



Greens senator Larissa Waters said the bill “sends the message to the public that the environment minister doesn’t have to make science-based decisions”.



She said the bill took away the community’s right “to challenge past decisions that might have been incorrectly made”.



The bill passed in the lower house with Labor’s support. The Senate is expected to debate it in the next sitting week, beginning 3 March.