Transportation Secretary Elizabeth Hanford Dole told Congress yesterday that it is time to "redefine the role of the federal government in transportation" as she strongly defended the administration's proposed elimination of Amtrak subsidies and deep cuts in urban transit aid.

Democratic and Republican members of the House Appropriations transportation subcommittee homed in on those two subjects to the virtual exclusion of the rest of the administration's proposed transportation budget for fiscal 1986 in Dole's first appearance on Capitol Hill to defend it.

The proposal would leave highway, aviation, Coast Guard and assorted safety programs virtually untouched while producing a 13 percent cut in overall spending, if approved by Congress.

Rep. William Lehman (D-Fla.), subcommittee chairman, first read from the Constitution about promoting "the general welfare" and defined transportation as being part of the general welfare. Then he observed that "the 13 percent decrease is not equitably distributed -- it's almost all in the Urban Mass Transportation Administration and the Federal Railroad Administration," which handles Amtrak subsidies.

"Why do you believe that's equitable?" Lehman asked Dole.

She replied, "Looking at the current situation, the deficits, it is appropriate we redefine the role of the federal government in transportation. We should be concerned about programs that impact nationally. When they are regional or local, we may have to do some redefining."

She said that Amtrak carries only 2 percent of intercity passenger trips nationally and only 10 percent of intercity passenger trips in the Northeast Corridor, between Washington and Boston.

Dole said Amtrak passengers get a subsidy of $35 per trip, about 55 percent of the people who ride Northeast Corridor trains are paid more than $30,000 annually, and federal subsidies to Amtrak will total about $8 billion over the next decade if nothing changes. "So we have to look at where the priorities are," she said.

Dole said she does not accept Amtrak's assertion that the end of federal subsidies means the end of Amtrak, particularly in the Northeast Corridor, and she said John Riley, head of the railroad administration, had been instructed to contact interested states and promote interstate compacts or other methods of finding state and local subsidies for Amtrak.

"I just can't go along with a proposal to eliminate Amtrak," said Rep. Silvio O. Conte (R-Mass.). He attributed the suggestion to "the young slasher," an obvious reference to Office of Management and Budget Director David A. Stockman.

Mass transit systems can raise fares, sharpen management and cut service to the suburbs to make up for the loss of federal assistance, Dole said. Federal aid for operating budgets, she said, is only "10 percent on average."

But Rep. Richard J. Durbin (D-Ill.) said, "You may be dealing with national averages, but you would put a burden" on three transit systems in his district -- in Quincy, Springfield and Decatur -- that "they could not handle." The system in Quincy, he said, received 55 percent of its operating budget from federal aid, and would simply have to close if the aid disappears.

"So you're cutting 55 percent in a budget that increases military spending 11 percent," Durbin said.

The budget would cut $2.7 billion in transit aid and leave $1.1 billion, which would be raised entirely by a 1-cent a gallon gasoline tax passed as part of the 5-cents a gallon federal tax increase in 1982. Rep. Lawrence Coughlin (R-Pa.) told Dole that the "penny on the gasoline tax was sold to us as additional funds for mass transit, not the total."

Conte also asked why the administration is willing to eliminate Amtrak subsidies but to continue to finance plans to reopen Union Station here.

"Maybe you should have alternative plans for Union Station, put in some stalls and hay racks," he said.

Conte also said he supported the administration's plans to charge user fees for some Coast Guard services. The fees, he said, "wouldn't cost, on some of those boats, what they pay for their Guccis . . . . It's a beautiful playground out there and we don't even charge admission."