A tentative Harvard Parking Office plan to redirect Yard traffic from Johnston Gate to Widener Gate has touched off a dispute between two unions over the employment of security guards who may be terminated in the move, a union leader said this week.

The plan, designed to reduce daytime traffic congestion in the Yard, was introduced early this month by Parking Office Manager Jeffrey L. Smith.

Controversy centers on the possibility that security guards now posted at the gates, members of the Service Employee International Union (SEIU) Local 254, will be replaced by parking "monitors" from the Harvard Union of Clerical and Technical Workers (HUCTW). It remains unclear why the transfer would take place.

"We will lose 18 guards [with this plan]," said Robert V. Travers, chief steward of Local 254. "We will refuse to negotiate a new contract on November 16 until [the provision to replace the guards] is dissolved. The University wants to get the two unions fighting," said Travers, who described the losses as significant.

According to Travers, the University employs about 100 security guards and 300 to 400 groundskeepers with SEIU.

Director of Facilities Maintenance Thomas E. Vautin, who originally conceived the plan to preserve the Yard environment, confirmed that the two unions are negotiating for the positions.

But George J. White, assistant manager of the parking office, said the plan is still tentative, pending Smith's return in November from vacation. White, who said he joined the parking office only this summer, added that the proposal is being discussed by Facilities Maintenance and other Harvard offices that often use vehicles in the Yard.

HUCTW spokespersons refused to comment on the possibility of a conflict between unions because the plan is still in the preliminary stages. According to White, changes to the proposal can be recommended until Smith returns.

The traffic management plan seeks to make aesthetic improvements and cut costs, in addition to relieving traffic problems, said Vautin.

"We felt the large vehicles detracted from the attractive and historical area as well as pose a health hazard for the over--populated Yard," Vautin said. "We also felt the extensive traffic caused significant expense to yearly maintenance."

If put into effect, the parking office would divert traffic by opening the gate behind Widener Library for major vehicle deliveries between 7 a.m. and 3:30 p.m. during the work week. Johnston Gate would remain open from 7 to 10 a.m., during which time service vehicles and those too large for the Widener Gate could enter through Johnston.

To reduce Yard traffic, the plan also emphasizes the use of a delivery service operated by Facilities Maintenance in the Science Center. Parking regulations around Harvard buildings near the Yard will also be tightened.