Mayor Mufi Hannemann and opponent City Councilwoman Ann Kobayashi challenged each other last night on their mass-transit solutions, political ambitions and stances on the island's only landfill in their final and most combative debate.

With a week left until the general election, Hannemann tried to discredit Kobayashi's statements, calling her “;confused”; several times throughout the night. Kobayashi, veering from her typically friendly demeanor, shot back angrily at times.

One of the sharpest exchanges of the night occurred during a segment that allowed the candidates to ask each other questions. Hannemann, in an expected move, brought up Kobayashi's last-minute filing for mayor that set in motion 2004 mayoral opponent Duke Bainum's uncontested run for her City Council seat.

“;There was obvious communication,”; said Hannemann, alleging that one of Kobayashi's allies had tipped Bainum off to her candidacy for mayor.

“;I don't know who that would be,”; Kobayashi said. “;The best way is to ask him. Instead of throwing out these innuendoes and whisper campaigns, just pick up the phone and ask him.”;

Last night's debate at the Hawaii Theatre, hosted by KGMB9 News and the Honolulu Advertiser and sponsored by the Office of Hawaiian Affairs, touched on a variety issues, including the closing of Waimanalo Gulch Landfill, Hannemann's refusal to commit to another four years as mayor and the most visible issue, mass transit.

Hannemann said he doubted the accuracy of the cost estimates of Kobayashi's $2.5 billion mass-transit plan developed in a couple of weeks with former opponent and University of Hawaii engineering professor Panos Prevedouros.

“;That's sort of insulting to the students of the University of Hawaii,”; Kobayashi said in a response to a question by moderator Peter Boylan, a Honolulu Advertiser reporter, that her plan isn't “;exactly cheap.”; Kobayashi said, “;Dr. Prevedouros and his students have been working on this for about four years.”;

On her transit plan, a 40-mile system that includes a 15-mile elevated three-lane highway for zipper lanes and a hybrid express “;rubber tire on concrete”; bus, Hannemann said, “;In the real world, you don't take three weeks to say you're going to spend $3 billion.”;

The two also clashed over the Waimanalo Gulch Landfill. Kobayashi criticized Hannemann for failing to close the landfill after taking office, and she proposes to find better technology to the city's incinerator to reduce landfill waste.

“;Once again, Ann, you're confusing the facts,”; Hannemann said, referring to a statement Kobayashi made that the city didn't look for newer technology. “;You voted twice to keep that landfill open. Let's be honest about our facts and voting record. You cannot run from your voting record.”;