The response to the announcement by premier Mark McGowan that Western Australia would be opened up to fracking has been first disbelief, followed by anger. History shows people are prepared to accept unpopular policies when a solid rationale is laid out based on sound evidence and analysis, but that is certainly not the case with this decision.

Journalists at the closed media briefing immediately saw through the disingenuous spin that 98% of the state will be frack free. Fracking 2% of WA is an area of 5 million hectares, or 50,000 square kilometres – around three quarters the size of the state of Tasmania.

But it’s the location of the fracking sites that is concerning: in the Mid West, directly covering the Yarragadee aquifer where Perth draws its drinking water; near Carnarvon, in the water catchment of fruit and vegetable growers producing much of our fresh produce; and a vast area in the iconic Kimberley, where many Traditional Owner groups have been calling for fracking to be banned.

By allowing fracking in existing petroleum leases, the new policy does little to reduce the area in which fracking would have been possible under the Barnett Government, which gave out petroleum leases like confetti with no community consultation or environmental assessment. So, it is essentially back to business-as-usual for the fracking industry.

Fears that allowing fracking in these areas is simply a way for the industry to get its foot in the door are already being borne out. An editorial in the West Australian newspaper enthused, “it should be possible before long to take the next step, and safely open up more than 2% of the state”. With no statutory protection for the frack free areas, that scenario will remain a distinct possibility.

Regarding the benefits of the fracking industry, the McGowan government can’t seem to get its story straight. On one hand, the fracking inquiry says the industry will be small in size, and therefore produce little pollution. On the other hand, the premier told ABC radio listeners, “it could be a very significant industry for Western Australia that could generate billions of dollars of royalties for the state and generate thousands of jobs”.

Most people would expect a major decision like this to be informed by economic analysis, however no such study has been done by the government. A briefing that had been arranged for MPs on the economic impacts of fracking by independent researchers at The Australia Institute (TAI) was vetoed by the premier. The economic impacts of fracking elsewhere might provide some clues as to why. In Queensland there has been a loss of 1.8 jobs in the agricultural industry for every new job created in fracking, according to the TAI research.

The research also shows employment of Indigenous people in the fracking industry is likely to be minimal, given most jobs are based in city offices rather than in the communities who will have to host the polluting gas fields.

The methodology used would struggle to pass a high school exam

It is also hard to believe McGowan’s claim that fracking will deliver “cheaper gas prices” for Western Australians. Any economist will tell you that the market price of a commodity is set by the marginal cost – or the cost added by producing one additional unit of a product. Since fracking is acknowledged by the industry to be a more costly way of producing gas than conventional means, the addition of fracked gas into the WA gas market is likely to have the opposite effect to the premier’s claim. Indeed, this is exactly what has occurred in the Eastern States, where the combination of demand from export market and the addition of costly unconventional gas developments has pushed up the overall gas price considerably.

As a nod to the landholders who have been protesting fracking so loudly, the announcement includes a new “veto right” where farmers and traditional owners can say “no” to fracking on their land. This sounds useful, but in practice it is not giving much comfort to landholders. In the Mid West, gas companies have already been buying farms so that they can avoid protracted negotiations with farmers seeking to protect their land and water. However, the surrounding landholders and community who will bear the impacts from pollution, noise, and other loss of amenity will be given no such veto.

People protest fracking in Western Australia. Photo supplied by Conservation Council of Western Australia Photograph: Supplied

It is in the area of carbon pollution and climate change that the fracking decision is so fundamentally out of step with science and public sentiment. It is also a clear breach of the the premier’s 2017 election commitment to conduct a “full lifecycle assessment” of pollution from fracking, and to maintain the fracking moratorium if fracking were shown to “contribute adversely to climate change”.

In September 2018, 50 of Australia’s leading climate scientists and experts signed an open letter to the McGowan government calling for a statewide ban on fracking due to its profound impacts on the climate, saying: “Unconventional gas resources in WA are one of the largest unexploited potential sources of carbon in the world. Opening these to exploitation would, in our view, be grossly irresponsible given urgency of the climate situation”.

The signatories to this letter include a “who’s who” of climate science in Australia, but the fracking inquiry refused to meet with them. Unsurprisingly, the inquiry, which did not have a climate scientist, reached a very different conclusion to these and other climate experts. Their report, which was suppressed until the government’s decision was announced, lays out how they reached their unlikely conclusion.

First, the inquiry simply ignored the largest share of pollution from fracking – the combustion of the gas it would produce, which would be responsible for up to 80% of total “lifecycle” emissions from fracking.

Second, and without any economic analysis to support this position, the inquiry assumed that fracking developments would be small. Rather than using the government’s own figures of the size of the “economically recoverable” gas resource, the inquiry inexplicably ignored the potential for fracking to supply established gas export markets, instead concluding only small scale developments for the local market would occur.

Finally, the inquiry argued that fracking would somehow lead to less development of conventional gas, so the only pollution that should be considered relevant is the difference between the two sources. For this to be true, it would require existing gas companies to voluntarily leave their conventional gas in the ground. This is an absurd proposition, however that did not stop the fracking inquiry from using it as a way to downplay the pollution from fracking.

Many assessments of carbon pollution from developments are undertaken every year, but very few are as misleading or ill-founded as the carbon analysis included in the fracking inquiry. The methodology used would struggle to pass a high school exam, and would certainly be rejected by the EPA if a proponent attempted to submit such an analysis. It certainly should not be relied upon by the community or government to inform policy on critical issues such as fracking and climate change.

The McGowan government’s decision to allow fracking in WA based on such analysis is a serious breach of the trust that thousands of Western Australians placed in the WA Labor party before the election. When people cannot trust the information that government decisions are based on, they not only reject the decisions, but the overall trust in government is undermined.

This decision will mobilise and radicalise our community and overshadow the positive environmental achievements of WA Labor. Like a barnacle on the government, this concern will continue to grow until a permanent statewide fracking ban is put into legislation.

• Piers Verstegen is the director of the Conservation Council of Western Australia