The fast-track proposal for the company’s Central Otago gold mine is at the stage of short hearings in Wellington. The focus yesterday was just on one witness, who appeared because she is unavailable next week.
Water scientist and ecologist Kate McArthur, of Palmerston North, addressed the hearing panel on behalf of Fish & Game Otago.
Ms McArthur said there was a cascade of uncertainty around water at the site and the receiving environment.
There was a lack of detail from the applicant around water and contaminants and how they moved through the site and uncertainty about the models developed and their inputs.
Key receiving environments, including the Ardgour and Bendigo aquifer, had not been assessed, despite clear hydrological connectivity and the potential for contaminants to migrate down gradients with limited attenuation or dilution, she said in her written evidence.
She could not understand the potential of what the effects were, given the information they had been given.
There was also a lack of ecological assessment in the receiving environment.
She said no ecological values had been valued by the applicant such as irrigation, stock water and recreation.
"Experts collectively have done some work to understand these values. But there is a dearth of information about what is the base line and around the water quality," she said.
Values could have been identified in the receiving environment and trout was recognised at both a national and regional level in waterways in the area.
Trout were land-locked in the Lindis River and went down to Lake Dunstan and into the Clutha River.
She could not give any confident view on how the effects could be managed into the future in several hundred years, given the lack of information.
"If we get this really wrong the scale of effect could be great. The probability of that happening — I can’t comment on because of the level of uncertainty at the moment. Some of the issue arises out of not really understanding what the potential effects are at this stage," she said.
"The ability to read the effects is highly uncertain. I cannot look into the future and see what the applicant is going to do."
She said there was a large basket of work which needed to be done up front. There was a smaller basket of work that could be done as the project went along.
She unequivocally said it was technically possible to produce a suite of results rather than how the experts from the applicant had produced their reports.
More water evidence was due to be discussed on Monday.
