Two days after Honolulu Mayor Mufi Hannemann vowed to fight the EPA over charges that Honolulu's wastewater treatment isn't up to snuff, he lashed out at Gov. Linda Lingle for agreeing with the EPA assessment and then criticizing the city for discharging untreated sewage in the ocean — a statement Hannemann said only "showed her ignorance of the issue."

The mayor criticized Lingle in a statement concerning comments she made to reporters on Friday in response to questions about an EPA announcement on Wednesday that the city's Honouliuli Wastewater Treatment Plant does not meet federal water quality standards, and that the EPA is now reviewing the city's Sand Island wastewater treatment plant.

At the same time the EPA issued a tentative decision against renewing a city permit variance exempting the 'Ewa plant from "full secondary treatment requirements."

Revoking the permit exemption could unnecessarily force the city to spend hundreds of millions on secondary wastewater treatment upgrades, said the mayor.

The mayor said there's no evidence the plant's discharge is harmful to people or sea life. He called the EPA decision unfair to O'ahu residents.

However on Friday Lingle said, "Actually, I agree with the EPA's decision," when asked if she would be willing to assist the city in its wrangle with the EPA. Then she added that she didn't think the city should be "dumping untreated sewage into the ocean."

It was the "untreated sewage" part that outraged the mayor to the point of accusing Lingle of not knowing what she's talking about.

"The governor showed a total lack of understanding when she characterized the city's treatment of wastewater," said the mayor, who contends the water at the 1980 'Ewa plant is, in fact, "treated."

While the plant may lack full secondary treatment capabilities, it does treat 27 million gallons of wastewater daily that it discharges through the Barbers Point deep ocean outfall — a mile and a half out to sea, in waters 200 feet deep. The plant also uses a secondary and tertiary process that treats up to 12 million and 13 million gallons respectively each day for industrial and irrigation purposes.

According to Russell Pang, the governor's chief of media relations, Lingle made the comments at a routine press event in response to a question about Wednesday's EPA announcement. He said Lingle commented that Maui had outlawed dumping wastewater into the ocean back when she was mayor of that county.

But Pang said the governor said that if Hannemann wants, "she would be happy to sit down and discuss what options there are and what they could do to work together on it."

Pang described Hannemann's statement yesterday as "a little strong."

Hannemann has said he disagrees with the EPA's conclusions, and said upgrading both plants would cost taxpayers more than a billion dollars and could catapult Honolulu homeowner sewer fees to $3,600 a year within the next two decades.

Reach Will Hoover at whoover@honoluluadvertiser.com.