The $350million plant has been told by the two authorities processing the company’s resource consents it must carry out a cultural impact assessment for its application.
The consents are being processed by Environment Canterbury (ECan) and the Waimate District Council (WDC).
South Island Resource Recovery Ltd (SIRRL) was notified this week that the application would not be processed until it also received a completed cultural impact assessment report.
It originally applied for its consents in September but the authorities sent them back, wanting more information.
More work was then done by SIRRL on the consents and they were sent to the two authorities last month.
SIRRL director Paul Taylor said the refiled application had addressed many of the matters raised in the previous application.
"However, the councils said that neither would accept the application until a cultural impact assessment, already under way, was complete and submitted," Mr Taylor said.
SIRRL was considering legal advice at present on whether this decision was a breach of legal process, and whether processing of the other reports that made up the Project Kea application should proceed in the meantime, he said.
He said SIRRL would formally reply to both ECan and WDC on the matter by the end of this week.
The proposed plant could convert 350,000 tonnes of waste into renewable energy each year, by burning rubbish to create steam which would then be fed through a turbine to produce electricity.
Waste materials delivered to the plant would be contained in a negative pressure bunker, and all emissions from the processing would meet air quality and noise standards, according to SIRRL.
