Scientists warn fracking for oil and gas could poison underground aquifers.
Parliamentary Commissioner for the Environment Jan Wright on Tuesday release a report that concludes fracking can be done safely in New Zealand, but current regulations are fragmented and light-handed.
University of Canterbury environmental chemist Sally Gaw told the Science Media Centre that that even if rules were tightened, there was still the possibility of blow-outs, mechanical failure and human error causing soil and water contamination.
"The consequences of a contamination incident have been understated in the report as there are limited to no options for remediating groundwater and soil once contamination has occurred."
GNS Science petroleum geoscientist Rosemary Quinn downplayed the effects of earthquakes, produced by fracking - or injecting water and chemicals into the ground to fracture rocks and release oil and gas.
Any earthquakes caused by fracking - identified in the US, UK and Canada and up to 3.8 in magnitude - would be small and not stand out against any of New Zealand's regular quakes, she said.
University of Canterbury and Lincoln University freshwater scientist Jenny Webster-Brown has concerns about the potential contamination of groundwater aquifers by fracking chemicals and deep oil field saline brines.
"Such contamination has been reported from countries where there has been a longer history of fracking, who have suffered the consequences of leaking well casings and blow outs," she says.
She further questions the need for fracking.
"From a philosophical standpoint, I'm afraid I cannot see why we should risk the environmental effects of fracking, in order to extract every last drop of the non-renewable fossil fuel resource.
"It is a stop-gap measure at best, and one which we could well regret. Surely the money and ingenuity dedicated to the development of fracking technology would be better redirected into the development of alternative fuels?"