Thomas R. Waldron realized how important his new job as manager of Virginia's planned commuter rail service is to the region's commuters when he went furniture shopping.

Waldron mentioned to the saleswoman that he recently had been hired to run the Virginia Railway Express, scheduled to begin carrying passengers from Fredericksburg and Manassas to the District's Union Station in October 1991.

"She said, 'You're the guy. I can't believe it. I didn't think you existed,' " said Waldron, who started working 12 days ago. "She gets up at 5 a.m. to beat the traffic. That's obscene."

With only 13 months to pull together the $60 million commuter rail service, Waldron faces unique challenges.

Most platforms and parking lots haven't been built or designed, fares and schedules haven't been set, and the locomotives and passenger cars are still being built or refurbished.

The six governments sponsoring the rail service hired Waldron because they believe he can make it happen.

His "experience was ideally suited for the kind of work we had," said Prince William Supervisor Edwin C. King (D-Dumfries), chairman of the railway's operations board. "He had worked with multi-jurisdictional {organizations}, had in effect started a new line, and had experience working with Amtrak."

Two years ago, New Jersey Transit Corp. gave Waldron nine months to start its 58-mile Atlantic City line. That line not only started on time, but now runs 11 round-trip trains, serving between 1,500 and 1,600 passengers daily.

"I needed to find a person I could count on to pull off a complex job," said Waldron's former boss, George Warrington, acting executive director of New Jersey Transit Corp. "When you give {Waldron} a job, he is obsessed with getting it done on time and on budget and with very high quality work."

Waldron, 34, began working in transit planning shortly after graduating from the State University of New York with degrees in economics and political science. He worked first with a suburban New York commuter line called Metro North and then with New Jersey Transit.

His interest in designing cities dates to his childhood in Peekskill, N.Y.

"I went to the '65 World's Fair in Flushing and went to the GM pavilion where they had a futuristic city and I was just awed. From then on I wanted to do something in urban planning," he said. "Unlike many other jobs, there are real tangible {results} when you've done a good job," he said. "You improve the quality of life."

Waldron, who will be paid $70,000 a year, doesn't have his own staff, or even his own office. Instead, he must borrow from the commissions the local governments set up to finance the railway. Waldron also has no direct control over the timing or the construction of the 16 railway stations and parking lots.

Some stations and parking lots already have been designed by Virginia Department of Transportation engineers, but local officials are still looking for land on which to build the Brooke station in Stafford County and the Fairfax Station. Many sites also need major road improvements.

The fate of a 17th station, in Spotsylvania County, south of Fredericksburg, is unsettled

The railway also has to work out formal leases for right of way on which to build the platforms with the three freight railroads that own the track, said Stephen MacIsaac, attorney for one of the sponsoring commissions. In addition, keeping the car and locomotive manufacturers on schedule could be difficult because the plants are in Brazil and Pennsylvania, respectively.

Waldron said his other key task is to find out what commuters really want. Railway planners expect the service to draw 4,000 round-trip passengers daily, but their projections may be outdated and do not specify what times people prefer to travel.

"I've also got to be sure the public is educated on how to use the system . . . what the advantages are," Waldron said.

As planned, Virginia Railway Express will provide eight daily round trips: four on the 40-mile Manassas line and four on the 55-mile Fredericksburg line. Daily round-trip fares are expected to average $5 to $8.

The operations board recently received proposals for fare card machines, which would accept only credit cards, and Waldron wants to establish a network of convenience stores and banks that would sell daily, weekly and monthly tickets.

Waldron said he is confident the rail service will start on time.

"This rail service will start in 1991. That's what I was hired to do and if I don't do it, I won't be here," Waldron said.

The local officials who hired him are up for reelection in November 1991.