STEPHENSON -- The two utilities behind the proposed Potomac Appalachian Transmission Highline are putting their best foot forward.

Officials from Allegheny Power and American Electric Power held an extensive briefing for reporters on Wednesday in advance of public hearings on the project.

The $1.8 billion, 765-kilovolt line is proposed to run from St. Albans, W.Va., to Kemptown, Md., via northern Frederick County.

Much like its controversial sibling, the Trans-Allegheny Interstate Line, PATH is designed to give electricity another route across the Appalachians into the high-use areas of Northern Virginia and farther up the East Coast.

Some environmental groups oppose the line, in part because it would bring power from coal-fired power plants from West Virginia to points east.

That would increase pollution and carbon dioxide emissions, according to court papers filed by the Sierra Club this week.

But utility officials are quick to point out that all electricity, regardless of whether it comes from a wind turbine or a coal-fired power plant, has to move across the grid to reach users.

Building PATH will make the region's grid much more fault-tolerant, the utilities say. As it stands, only one or two key line failures during a time of high demand could lead to brownouts or blackouts.

"It really is a mid-Atlantic grid reinforcement," said Mike Gogol, a consulting engineer with Allegheny.

Electricity flowing along the line won't just go to power-hungry Northern Virginia, Gogol said. Allegheny's Northern Shenandoah Valley service area will also benefit.

"It's kind of like you've got a bunch of water pipes coming out of a bucket, and the water is going to go every direction where the pipes are headed," he said.

A number of residents who live near the corridor have expressed concern about the noise that will be generated by the line.

That's understandable, according to utility officials. All high-voltage transmission lines generate "corona" effects, which include interference with AM radio signals and some noise.

Corona noise was quite audible standing directly under the existing Mount Storm-Doubs line on Wednesday afternoon -- a low, quiet half-buzzing, half-crackling sound just loud enough to remind those standing nearby of the immense amounts of energy flowing just overhead.

High humidity and drizzle made the effect louder than normal, according to Archie Pugh, a project manager with AEP.

But the noise lost its impressive character quickly, dropping off to inaudible levels just a few dozen feet away from the midpoint of the right of way.

Engineers weren't thinking about sound when they built the Mount Storm line in 1961, according to Les Gilpin, manager of transmission lines maintenance for Allegheny.

PATH should be quieter than the existing line, according to Pugh.

Instead of pushing the power through just six conductors like the Mount Storm-Doubs line, PATH will use a 18 separate strands.

"That creates a more efficient system to move the electricity," he said. "The good thing about that, when compared to our older 765 designs, we can reduce the noise at the edge of the right of way almost in half."

PATH will consume little new land not already covered by transmission lines, according to the utilities.

In fact, the new towers will also carry an existing 138-kilovolt line, eliminating almost an entire set of towers.

The Virginia State Corporation Commission will hold a two-day hearing on the line beginning Monday at John Handley High School. The hearing will begin at 2 p.m. and reconvene at 7 p.m. It will continue on Tuesday at 10 a.m.