The state's largest wind farm, under construction immediately south of this Hi-Line town, will be finished in five months, officials with the San Francisco-based company said at the site Wednesday.

Glacier Wind Project, which will produce 210 megawatts of electricity, is being constructed under the direction of general contractor Mortenson Construction out of Minneapolis.

Spain-based NaturEner, whose U.S. headquarters are in San Francisco, is the owner/operator.

Work began earlier this spring and NaturEner has scheduled an Oct. 31 completion date, NatuEner's Bill Alexander and Dave Dumon said.

"Put it this way, nobody at this site will be taking any vacations between now and then," Alexander said.

The aggressive construction scheduled is no coincidence, as a federal production tax credit for wind developers expires Dec. 31.

June typically has slower wind speeds, which also is guiding the ambitious construction timeline.

"Once you start lifting to 250 feet, everything is blown around," Alexander said.

The $400 million Glacier farm will be larger than the Judith Gap Energy Center, which is currently the state's biggest wind farm.

The wind farm's 140 towers, each 250 feet tall, aren't up yet, but parts are beginning to arrive.

On Wednesday, blades weighing 13,000 pounds each with 120-foot spans, as well as sections of 90-ton steel towers, sat beside foundations filled with 400 yards of concrete and set 20 feet into the ground.

Cranes 300 feet tall waited nearby.

"It's like a big Erector set, except everything has to be a little bit more precise," said Dumon, as he drove along one of the new roads crossing the prairie.

Towers will be erected beginning in about two weeks.

Even in Wednesday's sprinkling rain, there was no dilly-dallying at the 32-square-mile site, which is located between Highway 2 and the Marias River.

Contractors, who are working six days a week, were cutting new roads. Concrete tower foundations were being prepared.

"It's really weird for me to have to use my blinker out here," said Dumon, who helped arrange the land leases needed for the project.

The project currently employs about 100 workers, a number that's expected to rise once towers begin going up.

"The process is very much like an assembly line," Alexander said.

Towers will go up from east to west.

The area's wind blows best during the winter.

"It's not the best," Alexander said, "but it is an above average site for Montana."

Electricity from the wind farm will connect to the grid via NorthWestern Energy and Glacier Electric lines and sold to an out-of-state customer that Alexander said doesn't want to be named.

If additional transmission becomes available, more turbines could be added in at the site, he said.

Dumon and Alexander, then owners of Great Plains Wind and Energy, began putting the Glacier project together in February 2005.

The company later merged with NaturEner.

"It's very capital-intensive business," Alexander said. "The company we had was a development company only."

Besides the Glacier project, NaturEner has 750 megawatts worth of wind projects planned in Montana and 1,000 megawatts in Alberta, Canada, Alexander said.

"It's going to be limited by the amount of transmission that's available," he said.

While Alexander has been involved with dozens of wind construction projects in his career, the Glacier project is a first for Dumon, and he couldn't be more pleased to be a part of the development.

The 61-year-old, who is originally from Kevin, Mont., is old enough to recall the jobs that were lost when area oil refineries shut down years ago.

"To bring this back to the county that I grew up in is really kind of thrilling," Dumon said.