The Senate Appropriations subcommittee on transportation added $6.8 million yesterday to an appropriations bill to provide funds for the widening of a heavily congested stretch of Jefferson Davis Highway (U.S. Rte. 1) in Crystal City.

The money was added at the request of Rep. Frank R. Wolf (R-Va.) and Sens. John W. Warner (R-Va.) and Paul S. Trible (R-Va.), after Arlington and Virginia officials complained that the $2.7 million in a House-passed appropriations bill was inadequate.

"We certainly appreciate the Senate's action," said Arlington County Board Vice Chairman Mary Margaret Whipple. "We were so surprised to find it was not in the House appropriations bill that this is certainly a welcome change."

"That's great," said Donald M. Wagner, urban programs engineer for the Virginia Highway Department. "We could use more, but that's a big help."

The Virginia lawmakers asked the Senate subcommittee to add $7.3 million, and were satisfied with the amount approved, according to a Wolf aide. Wagner said that some work may have to be delayed if more state money is not found, but that most of the project can proceed on schedule.

Earlier this week, Arlington County Board Chairman John G. Milliken sent letters to Virginia congressmen complaining that the House transportation bill did not included $16.2 million needed for the long-awaited Rte. 1 improvements. The letters sparked charges by Wolf that Milliken was "grandstanding." Milliken, a Democrat, is frequently mentioned as a possible challenger to Wolf.

The project calls for the widening of Rte. 1 from four lanes to six through Arlington, starting at S. 12th Street near Crystal City, and running to Reed Avenue in Alexandria. State officials hope to begin early next year, and expect the project to cost $40 million.