In February, multiple people were arrested while protesting Whitehaven and Idemitsu’s approved clearing of the Leard State Forest to expand their mines.

The clearing must stop once the temperature hits 35 degrees, as animals become too hot to flee the imminent danger.

Activists claim forest was cleared illegally during extreme heat, with Front Line Action on Coal protesters on the ground recording temperatures above 35 degrees.

Department of Planning and Environment (DPE) investigated the claim and found the Boggabri, Tarrawonga, and Maules Creek mines were “operating at a high-level of compliance with the clearing commitments”.

“Weather stations were audited to ensure they comply with relevant Australian standards, and their locations and maintenance records were also checked,” a spokesperson said.

“The mines were found to be meeting their consent requirements to monitor temperature and stop clearing at the 35 degree limit.”

Leard Forest Alliance spokesman Phil Sparks said the investigation didn’t change the irreversible damage the clearing was doing.

"You can't mitigate the impact the land clearing is going to have on the endangered species of the forest," Mr Sparks said.

"Those couple of degrees is a very small comfort to the animals that had their homes knocked down. 

"Even if they did escape, there is a very high mortality rate. You can't force species into other habitats where there are no vacant niches for them to set up camp, it's not that simple.

"We want to know how many endangered plants were destroyed and how many animals were killed or displaced, they would be more relevant facts."

A Whitehaven spokesman said environmental compliance was incredibly important to the company.