The soil scientist who found the 'landfarming' of oil industry waste in Taranaki was sound says he didn't know livestock was being exposed to the waste on some farms before it was safe.
Doug Edmeades said the Parliamentary Commissioner for the Environment's recommendation for the government to intervene and to stop it happening is a "no-brainer".
Dr Edmeades, produced a report in 2013 for the Taranaki Regional Council that found that over time microbes in the soil had broken down the petrochemicals, heavy metals and salts in the waste and that the pasture on the so-called landfarms was fit for livestock.
Dr Edmeades said he never came across livestock grazing in untreated oil industry waste during his research and said it is not on that there are no rules stopping livestock being in the waste before it's safe.
He says the Commissioner's recommendation is common sense.
"Well that part of the report I think that's a no-brainer - it most certainly should keep animals out of those landfarms during the process in which the material is being incorporated into the soil that is just common sense to me," Dr Edmeades said.
"I actually don't know whether its a requirement of the consent that the animals are kept out, but if its not in the consent it most certainly should be."
Taranaki Regional Council said it does does not condone livestock grazing on active landfarms, but is adamant it does not have the ability under the Resource Management Act to regulate livestock on landfarms areas.
It said this sits outside of the Council's jurisdiction.
Dr Edmeades said while he appreciates the Commissioner's recent oil and gas report wasn't just about landfarming - he would have liked to see more information in the report on the landfarming process to let the public know how much monitoring of the sites goes on.
Environment minister Amy Adams has said she will consider the Commissioner's recommendation to keep livestock out of the oil industry waste before its safe.