The United States Postal Service's planned 20 percent reduction in starting pay for new employees may result in long-term savings in labor costs, but it could lead to ''some sort of action'' by unionized workers who are barred by law from striking.
Although Moe Biller, the president of the American Postal Workers Union (APWU), said in Washington that he would not rescind ''immediately'' a call for calm and for business as usual among angry workers, he no longer intends to emphasize it.
The reaction was the same in three other unions which, with the APWU, represent 600,000 postal workers. A spokesman said the imposition of a dual-pay system ''certainly increases the chances that resentful workers will undertake some sort of action.''
No retaliatory steps are expected before the two largest unions, the APWU and National Association of Letter Carriers, hold separate conventions the week of Aug. 19. Those unions are expected to coordinate policies for tackling Postal Service bargaining.
Indicating the growing tension, Mr. Biller said that at a time when the principle of equal work for men, women, and minorities has been established, it is obvious that the Postal Service ''under the Reagan-dominated board of governors is fighting to end this and make it unequal pay for equal work.''
''We won't tolerate this,'' Biller said.
The Postal Service is now a quasi-federal agency. Although technically independent, it is supervised by a board of governors named by the president and depends on financial aid from the US Treasury. Before the start of 1984 contract negotiations, the board pointed out that the Postal Service pays wages that exceed those for similar work in private industry. It told contract negotiators that labor costs must be reduced 20 percent or more over the next three years.
Following instructions, Postal Service negotiators proposed a three-year wage freeze for those now employed (who average $23,238 a year in pay and $4,655 in benefits). At the same time, management negotiators asked the unions to accept a reduction of about 20 percent in starting pay and cuts in sick leave and annual leaves for all who are newly hired. Unless changed in future bargaining rounds, such a lower wage base would affect the workers' earnings throughout their careers.
This proposed disparity was the key issue in bargaining, with both sides frozen into demand and rejection positions as contracts ran out last Saturday.
Because of the prohibition against strikes in the Postal Service written into law by Congress, the deadlocked dispute went to fact finding as a step toward possible binding arbitration as a last resort, with a Dec. 10 deadline for a settlement.
Usually there are no changes in contract terms during fact finding and arbitration. But when contracts with its unions expired, the Postal Service elected to move immediately in imposing the dual-pay plan rejected by the unions.