Environment Canterbury (ECan) and the Waimate District Council yesterday released two decisions granting the consents for 35 years, clearing the way for the plant to be built unless there are appeals to the Environment Court.
Oceania acting chief executive Paul Park welcomed the decisions and said the aim was still to start production next dairy season.
The company had to raise $75 million in capital, but Mr Park was confident of achieving that by the deadline of March 31 for construction contracts to be let in April.
The granting of resource consents would give added confidence to investors, he said.
However, a Glenavy farming family objecting to the plant is not happy with the outcome, particularly the potential effect on its export peony business and the views from their house 2.5km away.
Andrew and Jane McFarlane had not seen the decisions when contacted by the Otago Daily Times yesterday but indicated they had given it "their best shot" in opposing the plant at a hearing in December and would not appeal to the Environment Court.
"Time and resources are against us," Mr McFarlane said.
Mr and Mrs McFarlane fear plans to spray milk waste from the plant on to land will raise groundwater levels and change nutrient levels, killing the paeony plants.
Mr McFarlane said yesterday there would be no consequences to Oceania if the paeony business was affected.
He also failed to see how conditions on landscaping would hide the view of the plant from their house.
The other objector, Murphy Farms Ltd, represented by Robin Murphy, had also not seen the decisions and said it was too early to make a decision on whether to appeal.
Mr Park said Oceania and its consultants were still working through the decisions but, at this stage, the company was happy the project could go ahead.
He did not think the company would appeal.
"It's pretty much what we want."Oceania earlier this month extended the deadline for raising $75 million in capital for the plant from investors and farmers.
Mr Park said some were waiting for the outcome of the resource consents process.
"That plays a big part - in some respects, it's a confidence thing and certainly significant for investors," he said.
The two major issues identified by the hearings panel in its decision were the effect of the plant on groundwater and the view from the McFarlanes' house.
It was satisfied the wastewater treatment system would not raise groundwater levels but called for ongoing monitoring of groundwater levels and quality and imposed a review condition to enable measures to be taken to mitigate any adverse effects.
The panel acknowledged the plant would be "an unwelcome intrusion" on the McFarlanes' rural outlook but "we could not accept that the effects on landscape values to one particular property in a rural environment of this nature are fatal for a grant of consent".
However, it imposed four mitigation measures, including extra landscaping, colours used on the plant and a variation in materials.