Partner Highlands Pacific said the PNG Supreme Court chief justice declined to hear an injunction application by local landowners and would convene a full bench to hear the application on August 19.
However, it said project operator China Metallurgical Construction Company subsidiary MCC Ramu NiCo had committed to not using the deep-sea tailings placement system while it carried out current work and commissioning tasks.
The National Court of Madang last week removed injunctions holding the joint venture back from undertaking deep-sea tailings placement.
"It was expected that the plaintiffs would appeal the National Court decision," Highlands Pacific managing director John Gooding said.
"At this stage we do not believe the project will be further delayed by these legal actions and we remain confident that the decision in the National Court will be reaffirmed if challenged."
Located 75 kilometres west of the provincial capital of Madang, the Ramu mine is expected to produce 31,150 tonnes of nickel and 3300t of cobalt per annum in a high-grade concentrate over a 20-year mine life.
The resources could also potentially support mining for a further 15-20 years.
MCC Ramu NiCo owns 85% of the project, but Highlands' stake will increase from 8.56% to 11.3% once the project development debt is paid off, which could be in eight years.
The PNG explorer also has an option to acquire a 9.25% stake of the emerging mine at a fair market value, providing the potential for Highlands to increase its total stake to 20.55%.