Debris and weathered oil washed up on Mount Maunganui and Papamoa beaches over the weekend during the Cyclone Lusi storm.
Bay of Plenty Regional Council received complaints from beach walkers about oil on the beaches and alerted contractors Envirowaste. About 20kg of oil and debris was picked up on Mount Main Beach and another 15kg on Papamoa Beach by Envirowaste.
Regional council environmental management general manager Eddie Grogan said oil and debris on the beach was not unexpected after a storm, given the recent work to remove the top section of the accommodation block.
"It's a timely reminder that there are still small amounts out in the environment, and that's why we have a plan to deal with it after these events. We're grateful to members of the public for alerting us to the debris and oil so it can be promptly cleaned up," said Mr Grogan.
The Rena's owners are adding signs to beach accesses this week providing contact details if anyone finds oil or debris on the beaches.
Spokesman for Rena's owner and insurer Hugo Shanahan said he was aware some debris and small amounts of oil were recovered by the onshore debris management teams last Sunday and Monday.
"The oil would need to be fingerprinted to confirm its origin," he said.