A new report which found fracking could potentially set off "very tiny" earthquakes justifies Christchurch's frack-free status, mayor Bob Parker says.
In April, Christchurch became New Zealand's first fracking-free city.
Fracking - hydraulic fracturing - involves injecting water and chemicals deep into underground rocks to fracture them in an attempt to release oil and natural gas.
It has been banned in some countries after concerns over water and air pollution, and has been linked to small tremors.
Parliamentary Commissioner for the Environment Dr Jan Wright released an interim report into fracking yesterday.
She has held back from calling for a moratorium on fracking, but is worried about the way the process is regulated and monitored.
Her report also found the process could cause only "very tiny" quakes.
Parker said the report confirmed the council's decision was a "sensible" one.
"There are a number of questions that are still not answered to my satisfaction."
He highlighted the potential impacts on fault lines, particularly in a region that had been through thousands of earthquakes, and the possible contamination of water as reason enough not to allow fracking.
Meanwhile, the Greens have called for an immediate halt to fracking until strong regulations are in place, but the Government believes Wright's report into the controversial mining practice is an endorsement.
"During the course of this investigation I have come to a similar conclusion to the Royal Society which is that fracking is safe if it is properly regulated and managed," the commissioner said.
"But at this stage I cannot be confident that operational best practices are actually being implemented and enforced in this country."
She thought drilling companies were being trusted rather too much to all do the right thing and said she was concerned about how fragmented and complicated the regulations were.
"I am also concerned that regulation may be too light-handed, particularly if fracking opens the door to a large-scale and widespread oil and gas boom with a lot of different companies involved."
Those concerns will be the focus of the next stage of her investigation, which she hopes to finish by the middle of next year.
Wright said yesterday that if she found issues that were sufficiently worrying she would not hesitate to call for a moratorium, but did not think it was justified at present.
The Greens, though, want a temporary halt.
"The PCE's report does not say that fracking in New Zealand is safe; the report concludes that fracking companies do not have a ‘social licence' to operate and that the regulation is fragmented and light-handed," energy spokesman Gareth Hughes said.
Prime Minister John Key said it was a positive report. "What she is fundamentally saying is that it is safe to undertake fracking in New Zealand, but you need to carry out that fracking within world-class standards."
Environment Minister Amy Adams said she had told the Environment Ministry to create clear guidelines on the roles of central and local government in fracking control.
- © Fairfax NZ News
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