The NSW Environment Protection Authority has advised it cannot adequately assess the potential air quality and noise impacts from the Federal Government's proposed gas peaker plant at Kurri.
The authority made one of almost 260 submissions regarding the contentious $600 million project, currently under assessment by the Department of Planning, Infrastructure and Environment.
"The EPA has reviewed the environmental impact statement and notes that it does not provide the information required by the Secretary's Environmental Assessment Requirements to adequately assess the potential impacts to air quality and noise," the authority said.
Of the 257 submissions relating to the project's EIS, 221 were from individuals, 26 were from organisations and 10 were from public authorities.
Only two submissions were supportive of the project, while 217 were opposed to it.
Submissions made by public authorities were classified as comments.
The Department of Defence said the plant's design meant it would not adversely impact on RAAF and civil aircraft operations, however, it did request precautions be taken regarding gas plumes.
"Defence requests that a permanent charted danger area is to be promulgated using global airspace solutions dimensions to account for the vertical plume velocities generated from the plant," it said.
"The parameters of the Danger Area will include a vertical elevation of 884 metres and a horizontal radius of 155 metres, it should include a note to avoid the danger area."
The government argues the gas peaker is needed to fill the gap in dispatchable power caused by the closure of Liddell Power Station in 2023.
However, critics argue it is not needed, will only run for two per cent of the time and create 10 full time jobs.
The Australia Council said the strategic need for the project had not been established and it would displace other better feasible alternatives.
"The subsidised Hunter Power Project intervention is unlikely to result in lower electricity prices in NSW than if alternative capacity is provided by a market response," its submission said.
"This subsidised government gas intervention will displace investment in batteries and renewable capacity that would provide equivalent or greater reliability at a lower system cost."
But the Australian Energy Council argued that peaking gas should be viewed as complementary to, rather than a substitute for, renewable generation.
"The accelerating pace of the change to Australia's electricity generation mix brings with it opportunity, but also challenges," the council's submission said.
"Because these sources are variable, they require flexible and firm back-up capacity to cover periodic lulls in their output.
"Dispatchable generation, like a peaking gas-fired power station, is well suited to perform this role even as overall gas consumption declines."
Despite the objections, the Department of Planning, Infrastructure and Environment is likely to approve the project, which has state significant infrastructure status.
Lock the Gate spokeswoman Georgina Woods said the public submissions reflected the lack of support for the project in the wider community.
"The overwhelming percentage of submissions opposed to the Morrison government's foolish Kurri Kurri gas plant demonstrates just how few people would benefit from this polluting project," she said.
"No one wants this gas-fired failure.
"This is unforgivable in a place like the Hunter Valley, where unacceptable air quality is already a serious problem due to the presence of many open cut coal mines in the region.
"In fact, as the EPA also points out, Snowy Hydro has not conducted an ozone and inter-regional transport assessment, despite the proposed plant expected to emit ozone precursors, volatile organic compounds and oxides of nitrogen.
The Gas Free Hunter alliance recently gained 3400 signatures on an online petition opposed to the project.
The alliance has called on Energy and Environment Minister Matt Kean to reject the plant.
"We're in a climate crisis, you've got the International Energy Agency telling you no more fossil fuel projects if you want to meet the Paris targets, and you've had every climate scientist in the world, just about, telling you that for the last couple of years," Alliance member Janet Murray said.
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