Engineering Demands at the Colville River.

• Author: JONES, PATRICIA

Getting oil from the Alpine project to the trans-Alaska oil pipeline in an environmentally friendly way was difficult with a mile-wide river in the way.

The pressure couldn't have been greater. In March 1998, nearing the end of what would be the shortest season on record for North Slope oil field construction, managers of Arco Alaska Inc.'s headliner Alpine development were just a touch nervous.

That's because a key element of that $1 billion developing field-construction of an underground river crossing by means of a drilling technique new to the North Slope-wasn't proving up.

Crews had failed five times to bore a 4,500-foot hole underneath the Colville River in attempts to create a mini-transportation tunnel designed to carry crude oil from the remote oil field to existing North Slope pipeline structures.

Designers were scratching their heads trying to figure out how to apply this technology, called horizontal directional drilling, to Arctic conditions. Drillers from Outside were still coping with the operating changes required by the cold environment.

And time was quickly running out for that winter construction season, the only time that crews are permitted to work on the fragile North Slope tundra, protected by a deep layer of frost and ice.

Fast-track to the present Representatives from Arco Alaska and the project's designer, Michael Baker Jr. Inc., are just a touch nervous again. But for an entirely different reason-they're awaiting a decision as to whether this same Colville River crossing project, now nearly complete, will win a national engineering achievement award.

Already, the project's design has been selected by the Alaska section of the American Society of Civil Engineers for a state award. It was also named an outstanding project in the organization's western zone, according to Howard Thomas, past president of the Alaska section.

"Uniqueness was a big reason for the Colville project's selection for the state award," he said. "This directionally drilled river crossing was the first of its kind in the arctic and in permafrost."

Even Alaska Coy. Tony Knowles got on the bandwagon of praise for the project. In a supportive letter submitted to the national engineering organization, Knowles lauded the environmental attributes of the design and the new technology of boring under the river, as compared to more conventional bridge construction or trenching through the riverbed.

"The goal of the project was to leave behind nothing but...