The early price tag to the city for such an operation: about $7.8 million a year.

"It won't solve all your waste disposal problems, but it will provide a little breathing room as you move forward," said Jim Hodge, head of Pacific Rim Environmental Resources, one company seeking the job.

Council members must decide by December whether to expand the city's landfill at Waimanalo Gulch or seek approval for a new dump elsewhere. The city also is considering a $64.1 million expansion of its H-Power trash-burning facility.

O'ahu generates more than 1.6 million tons of solid waste annually. Under separate proposals presented yesterday, somewhere between 6 percent and 18.5 percent of that trash could be sent to the Mainland.

Pacific Rim Environmental Resources, which says it could have such an operation up and running in Honolulu within four months, has proposed charging the city $78 a ton for the service, with a clause that allows the cost to go up with the consumer price index.

Idaho Waste Systems, which is about 18 months away from a startup, has not developed a proposed fee schedule but would be competitive with Pacific Rim, said company Vice President Grant Gauthier.

Initially skeptical about exporting O'ahu trash, several council members said they now see at least some potential in the idea.

"The more I hear about it and research it, the more I think it might actually work," said Councilman Charles Djou.

Both waste haulers said they would put the trash in shipping containers that would otherwise be empty on their way back to the Mainland after arriving here full of building supplies and other material.

The key to making the trash environmentally safe is the shrink-wrapping process, which would kill any insect or microorganism inside by depriving it of air, they said.

Nobody at the presentations before the City Council's Public Works Committee yesterday suggested that the plan, if adopted, would cancel the need for a new or expanded landfill — a contentious issue that divides communities and makes politicians step lightly.

"We are going to have to select a landfill; we have no other option," said Public Works Committee Chairman Rod Tam. "There is no single remedy that is going to take care of 100 percent of our solid-waste problem."

Of the two proposals presented yesterday, Pacific Rim's was clearly more advanced, with detailed cost estimates and sites already identified for operations at Sand Island and Kalaeloa.

Its sanitizing system also has received key approval from the U.S. Department of Agriculture, Hodge said.

The company has years of experience shipping trash from Alaska to the huge regional landfill in Klickitat County in central Washington.

Idaho Waste Systems would use a similar bundling and wrapping system, then ship O'ahu's trash, first by barge and then by rail, to a site near Boise, Idaho, Gauthier said.

Despite the appeal of easing O'ahu's trash crunch, several people at yesterday's hearing urged the city not to rush into signing a deal with either firm.

• Councilman Romy Cachola worried how the trash diversion would affect revenue the city receives from landfill tipping fees now paid by private operators. "We might have to raise property taxes to cover the loss," Cachola said.

• Djou, Councilwoman Barbara Marshall and others wondered about the public relations fallout when Mainland tourists hear we are shipping our trash to their home states. "The last thing our tourist industry needs is negative publicity," Djou said.

• And Wai'anae resident Cynthia Rezentes warned officials the city would remain legally responsible for any environmental problems caused by the trash, even once it is buried on the Mainland.

Tam said the committee would hold another hearing Thursday to hear other proposals for dealing with O'ahu's waste.

City administration officials, who have been openly skeptical in the past about shipping solid waste to the Mainland, will present their own report on the idea, as well as its proposal to expand the H-Power facility, Tam said.