This editorial originally appeared in the Fairbanks Daily News-Miner:

Federal agencies appear to have agreed on conditions that will allow ConocoPhillips to build a bridge and pipeline across a Colville River channel on the North Slope. The agreement could help provide much-needed access to oil fields west of the river in the National Petroleum Reserve-Alaska.

According to Alaska’s congressional delegation, an agreement between the ConocoPhillips, the Environmental Protection Agency and the Department of the Interior should allow the U.S. Army Corps of Engineers to issue the necessary permits for the bridge and pipeline. This is good news for Alaska, which needs new oil to sustain its economy.

ConocoPhillips has pursued this project for nearly a decade. It needs the road to reach CD-5, a drilling pad for a satellite field in the Alpine development, and to provide a year-round road link to future development in NPRA. The company wants the pipeline to cross above the river on the bridge for safety and cost reasons.

The review process proceeded well until almost two years ago, when the Corps denied a permit to disturb wetlands in the area. An effort to reverse that decision stumbled on objections from the EPA and Interior Department.

To answer those objections, ConocoPhillips changed the bridge design and agreed to other measures, including an agreement to allow other companies to use the bridge, according to an announcement from the Interior Department.

The initial disagreement centered on the environmental impact of the bridge and pipeline proposed by ConocoPhillips.

The Corps, in February 2010, concluded that approving the company’s project would violate its guidelines. The Corps said it can’t allow such work in wetlands “if there is a practicable alternative ... which would have less adverse impact on the aquatic ecosystem.”

The Corps suggested the environment could be better protected by dropping the road and bridge entirely and by boring a tunnel under the Colville River’s Nigliq Channel for the pipeline. Access to the CD-5 site would have been limited to aircraft and vehicles traveling a winter ice road.

This certainly was an “alternative,” but it was hardly a “practicable” one, in that it offered far poorer access to CD-5 and other areas of NPRA that potentially could be developed.

The Corps, in announcing its initial decision to reject the permit, noted the Colville River Delta “is the largest and most complex delta on the Arctic coastal plain and drains nearly 30 percent of the North Slope.” The delta hosts migrating caribou and dozens of bird species and contains “nearly 70 percent of overwintering fish habitat within the North Slope,” it said.

But the roadless tunnel concept is of dubious advantage in protecting the delta environment. A road connection would reduce aircraft traffic and allow the company to build a smaller pad at CD-5, because it could share equipment with the main Alpine pad. Also, a pipeline above the Nigliq Channel would be more easily monitored for corrosion and leaks, an important advantage in lines carrying unprocessed North Slope crude oil.

All members of Alaska’s congressional delegation expressed hope Monday the new agreement would permit the Corps to issue the necessary permit. That’s the best practicable alternative. The Corps should take it.