RESEARCH TRIANGLE PARK - The N.C. Turnpike Authority's planned toll road promises six new lanes of parkway to ease the pain of Research Triangle Park commuters.

But Craig Alexander and other opponents or the road, to be called Triangle Parkway, say they don't want to pay for the privilege of driving to work. With the project looming, they vow instead to chart more circuitous routes to their jobs. Anything to avoid paying the toll, many parkway opponents say, but one of their go-to routes into the park would be cut off with construction of the parkway.

The half-mile extension of the Durham Freeway that currently links Interstate 40 to T.W. Alexander Drive would be closed with construction of the parkway. The project is scheduled to begin this summer, assuming the turnpike authority receives money from the General Assembly to cover an expected gap between toll collections and parkway costs.

The Turnpike Authority has projected that the new parkway could cut traffic on I-40 between 540 and the Durham Freeway by as much as 46,400 vehicles a day by 2030 and could ease congestion on RTP stretches of N.C. 55 and N.C. 54. But losing a free offramp linking the Durham Freeway to the Park does not seem worth the cost for Alexander and other commuters opposed to tolls.

"It would be nice to keep that spur open, because it's going to limit at least two of my alternative ways off of 40 home," said Alexander, who lives in the Parkwood neighborhood in Durham. "It's going to require me to go some alternative routes that take a little bit longer time."

Triangle Parkway tolls may range from 10 cents to 15 cents a mile, although the N.C. Turnpike Authority has yet to set rates. The authority first held a public workshop two years ago, but commuter criticism is now percolating on the eve of the proposed project.

A public hearing Feb. 13 drew about 150 RTP workers, and about 60 turned out for a hearing March 25. One opponent, Raleigh resident David McDowell, set up a "NoTollson540" Web site.

Concerns about noise and air pollution have some workers worried about the expressway's proximity to a day-care center on the RTP campus shared by the U.S. Environmental Protection Agency and the National Institute of Environmental Health Sciences.

The Durham Freeway spur that Alexander and many other RTP workers use would be closed to control access to the new toll road.

The N.C. Department of Transportation built the spur as a temporary connection. It has turned into a fairly elastic definition of "temporary." The Durham Freeway spur has provided access between T.W. Alexander Drive and I-40 for 21 years, enough time for commuters to develop a liking for that route.

EPA employee Sylvia Saracco also serves as president of the local chapter of the American Federal Government Employees union, which represents about 1,000 RTP workers. For all the RTP workers coming from Durham, Chapel Hill and other parts of Orange County, closing the Durham Freeway spur could end up lengthening their commute, Saracco said. Even if they use the parkway, she added, many of the 1,800 employees working on the joint EPA-NIEHS campus could end up fueling new traffic bottlenecks on Hopson Road as they try to maneuver to the back end of their work campus.

"This has a lot of people scratching their heads," Saracco said. "I'm sure there are some people who will use the toll road, but that seems like such a small area, I'm trying to see what the benefit is.

"If we're interested in looking at this issue, what about mass transit?"

Jennifer Harris, a Turnpike Authority engineer, said it would be difficult to determine individual motorists' future travel patterns or predict how many RTP commuters will end up seeking alternate routes to avoid paying a toll. Harris noted, however, that drivers will still be able to get off the Durham Freeway farther west of the Alexander Drive spur on N.C. 55, for example.

"We can't track every car and say right now, 'This one will use the parkway, this one won't,' " she said.

If the parkway opens in 2010 as planned, commuters willing to jump on the toll road have two more years to hoard change.