The Butler Transit Authority is seeking proposals to provide natural gas for its buses.

Authority board members agreed Tuesday to issue a request for proposals to provide gas for the compressed natural gas fueling station for five years.

“We’re looking for pricing for the next five years,” said John Paul, authority executive director

The station is nearly complete and will be tested on Dec. 18, he said. It is expected to be operational in January.

A temporary fueling station, which the authority leases for $7,500 per month, is currently being used to fuel the buses.

Three of the authority’s local service buses and all five commuter buses run on compressed natural gas. Three more gas-powered local service buses will go into service by April, Paul said.

The trolley bus, which runs local service routes, will be only diesel- powered bus in the fleet, he said.

The board is expected to vote on hiring a gas provider at its Dec. 11 meeting.