Rotorua ratepayers could be out of pocket by as much as $40,000 after last week's white powder scare at the Rotorua Lakes Council.
The discovery in the council's call centre last Thursday led to emergency services closing down the building and nine staff members having to go through a decontamination process.
The powder was found to be harmless.
At Tuesday's extraordinary meeting to debate the Te Arawa Partnership model councillor Charles Sturt said: "To the idiot who put the white powder in the envelope, you cost the ratepayers $40,000. It was a cowardly act."
He said yesterday that chief executive Geoff Williams had told him the clean-up figure before the meeting started, but Mr Williams has since said the council had yet to receive the final bill and that $40,000 "could be the upper limit of it".