You can almost feel the clenched teeth in Mayor Peter Carlisle‘s letter to the Honolulu City Council last week about the treatment of sewage at Sand Island.

It’s one of the few issues that Carlisle and the Council have really clashed publicly. They pointed fingers last summer and tried to assign blame for the budget cut that led to the city trucking raw sewage around the island.

The Council, particularly Romy Cachola, has continued to push for answers about alternate technologies for the plant — something to replace the fertilizer-pellet-generating system built by Synagro, which has had major problems elsewhere.

Now, Carlisle has pushed back. Here’s the graf that reveals the mayor’s frustration:

To our knowledge Synagro is not in breach of their contract with the city and the company has not bribed anyone or done anything else illegal within our state. If any councilmember has information to the contrary, as the former prosecuting attorney, I strongly urge that councilmember to immediately contact the federal bureau of investigation.

He also points out that it would cost the city $2 million to cancel its contract with Synagro. He said he hopes the letter “puts the question to rest until we all have a failsafe backup plan for the Sand Island treatment plant before us.”