New information shows Anadarko has modelled oil leaks using numbers far worse than Greenpeace used in its criticism of the Texan oil giant's deep sea drilling plans.
Prime Minister John Key had described Greenpeace's simulations as "scare-mongering", the environmental lobby group said today.
"Anadarko's modelling assumed a spill rate of 12,000 barrels of oil every day for one well location and 18,000 barrels at another," Greenpeace spokesman Nathan Argent said.
Greenpeace's own spill modelling report, released in October, assumed 10,000 barrels a day.
The data is contained in about 1700 pages of documents released today by Maritime New Zealand after an Official Information Act request for Anadarko's discharge management plan.
The plan is required of all offshore oil and gas installations, including exploration drilling and production facilities.
MNZ said the plan "establishes procedures and practices aimed at reducing the environmental impacts from discharges of harmful substances, including oil and chemicals, from offshore activities".
Greenpeace said the information from Anadarko showed a more than 50 per cent chance of oil reaching land in the event of a spill.
Anadarko's oil spill data estimated a spill would reach New Zealand shores in 66.05 per cent of cases in autumn and 51.82 per cent in summer, the environmental lobby group said.
The information was omitted from wider documents made available in September.
Greenpeace has argued in court that the Government's Environmental Protection Authority made an "error in law" by allowing the drilling programme without looking at these documents.
Argent said there was "more than a hint that the Government and the oil lobbyists colluded to keep this secret".
"They simply do not want the New Zealand public to know about the potential for an oil spill," he said.
The Green Party's energy spokesman, Gareth Hughes, said the documents showed New Zealanders had every right to be concerned about deep-sea drilling.
"A capping stack would take 33 days to get to New Zealand and a relief rig would have to come from East Africa and would take between 80 and 115 days to get here."
Key's claim Greenpeace had been scaremongering "was clearly ill-founded and playing politics", Hughes said.
It was outrageous that it took so long for the documents to be released. The public should have had access to them before Anadarko started drilling, he said.
- Fairfax Media
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