HILO — The county Environmental Management Commission is satisfied there's nothing improper about the administration's continued renting of a bulldozer it sold as surplus six years ago.

The county sold the 1991 Caterpillar D8 for $52,083 in 2003, as part of a trade-in for a new bulldozer. It has since spent more than $427,025 renting it back.

A contract with the owner, C&H Ishii General Contractors, will carry the county through June 30 for another $12,725 a month.

The county Department of Public Works bought the bulldozer new for $276,020.

The county is responsible for providing the operator and all required maintenance and repair. It's not known how much repairs and maintenance of the 18-year-old bulldozer have cost taxpayers over the years.

A used bulldozer of this kind would cost $125,000 to $150,000 to buy.

The commission in September asked county Environmental Management director Lono Tyson for justification of the county's actions following a West Hawaii Today report.

"If you delve into it, it makes sense," commission vice chairman Steve Pavao said Wednesday.

Tyson's report indicates the county Department of Public Works traded it in to Pacific Machinery for a new bulldozer more suited to road work. The county Department of Environmental Management then executed "emergency procurement" no-bid contracts with Ishii to temporarily replace bulldozers out for repairs. When the project was put out for bid, Ishii was the sole bidder until this year.

Ben Ishii, an engineer in the Department of Public Works, is a first cousin of C&H Ishii's president. He told West Hawaii Today that he has no involvement with the company.

Tyson says that renting the bulldozer has saved the county $7.1 million a year by helping keep the Hilo landfill open and avoiding trucking garbage across the island. He said the bulldozer is specially designed for landfill work, with a hardened undercarriage, closed cab and air filtration. "Based on the results of my review, it is apparent that no wrongdoing or mismanagement of county resources occurred," Tyson said in his report.

The county owns four bulldozers — two at each landfill. They are often down for repairs because of heavy use, Tyson said. But Tyson was unable to explain how repairing a bulldozer the county owns differs from repairing one it rents.

Hilo contractor Buddy Azevedo, contacted for his opinion, disputed that the Ishii bulldozer is specially designed for landfill work.

The "hardened undercarriage" is known as a "belly guard," and all bulldozers have them, he said. Closed cabs and air filtration are also common, he said. "This is a normal 'dozer," Azevedo said. "This is just one big cover-up, that's all."