Meeting minutes for the mine’s koala technical working group say there has been a steep drop in koala populations at the mine site in the Liverpool Plains.

Experts who sit on the working group have raised concerns the clearing of habitat for the project will accelerate this decline at a time when the species is under pressure as a result of bushfires, drought and chlamydia.

The Environmental Defenders Office has written to the state government on behalf of the Lock the Gate Alliance, asking it to suspend the approvals process for Shenhua’s koala management plan because the full impact of the project on the threatened species “cannot be adequately assessed” until the damage to koala populations and habitat in NSW caused by the bushfires is fully understood.

The EDO has also asked the federal environment minister, Sussan Ley, to use her powers to step in for other threatened species, including the regent honeyeater and the swift parrot, both of which lost habitat in the fires and were species considered in the original federal assessment of the mine.

But Ley has no power in relation to the koala because it was not listed as a threatened species under national environment law when the project was declared a controlled action that required federal environmental approval in late 2011.