Potential greenhouse gas emissions from the Northern Territory's largest-ever land-clearing project were not weighed because their impact on global warming could not be measured, the head of an environmental watchdog says.
Paul Vogel gave evidence this week in a landmark challenge brought against the EPA's decision to not require an environmental impact assessment of a proposal to clear 20,000 hectares at the Maryfield cattle station south of Darwin.
The case is considered to be the first in the Northern Territory to challenge the approval of land clearing on the basis of climate change impacts.
Lawyers for the Environmental Defenders Office NT argued the authority was wrong in regarding itself unable to consider the impact of the clearing's emissions because the Northern Territory had no climate policy and because the emissions would not have a nationally significant environmental impact.
The Supreme Court heard that estimates of the likely emissions were not provided to EPA members in the briefing papers prepared for them, despite officers from the Department of Environment and Natural Resources calculating an estimate of 2.3 megatonnes or 18.5 per cent of the NT's total annual emissions for 2015.
Dr Vogel said while the EPA seeks to ensure that proponents keep emissions as low as possible, the impact of activities from individual projects on climate change is not measurable.
"We did say [the proposed clearing] was significant in terms of emissions for the Territory but then you've got to turn your mind as a board to [asking] 'is there a significant effect of that?'" he said in court.
"The answer is 'it isn't possible to tell' so what we did, therefore, we said subjecting it to an impact assessment wasn't a reasonable thing to do."
'An inefficient tool'
Dr Vogel made his own estimate of the project's likely emissions volume based on photographs of the property's vegetation, which he considered similar to Western Australia's Pilbara region where he previously worked.
His predicted figure was less than half that of the environment department's but he said the difference was not scientifically material.
"From the point of view that global greenhouse gas emissions are about 40 thousand million tonnes per year, nationally about 560 [megatonnes], the Territory around 17, [the Maryfield clearing] might make a contribution of 1, 2, 5 or 10 [megatonnes]," he said.
"You would not be able to discern an environmental impact."
The barrister for the Environmental Defenders Office, James Hutton, pressed Dr Vogel on the position.
"It would not be acceptable assessment process for the EPA to proceed on the basis that because the particular project will not cause an appreciable impact on global temperatures then one might as well not worry about those emissions, would it?" he asked.
Dr Vogel replied: "No and that's not what the EPA did."
In its reasons for the decision to not require an assessment the authority said the Maryfield proposal raised policy issues around land clearing and climate change but that individual environmental impact assessments were "an inefficient tool for dealing with these broader, important policy issues."
It said the authority would instead raise the issue with the department and the Pastoral Lands Board.
Proposal raised 'flashing red' concerns: EPA member
The Environmental Defenders Office (EDO) lawyers also argued the authority's decision was invalid because the EPA had not followed its own meeting procedures nor voted on the final decision.
Emails discussed in court between the EPA decision-makers, who mostly live outside the Territory, revealed concerns raised by a number of members.
"My inconsistency radar is flashing red," wrote Dr Ian Wallis.
"For many projects with a much smaller area involved we have required extensive flora and fauna surveys."
Mr Wallis said the land-clearing proposal should be exposed to public scrutiny through an assessment process.
Another EPA member suggested the authority clear the project for approval only on the basis that it ensure recommended conditions were met.
Recommendations were made but some of the conditions were then rejected by the Pastoral Land Board, which ultimately approved the clearing.
The matter will return to court later in December.
