Most of the metro area's 23,382 blue collar federal workers are due two pay adjustments this month. Amounts of the increases have not been set, but they cannot exceed a total of 7.02 percent.

The first raise is retroactive to Oct. 1. It will go to any blue collar worker who was due to get more than 5.5 percent last year as a catchup with local industry. Congress limited employes to 5.5 percent last year, but that fiscal year ceiling expired Sept. 30. Employes due more money will get retroactive checks representing their new, higher rate from the beginning of this month.

A second raise will go into effect Sunday. It is the regular October adjustment government makes here to bring federal blue collar rates into line with salaries for similar jobs in private industry.

Many blue collar workers will get both the retroactive raise, and the new raise. Some will get only the 1979 catchup-with-industry adjustment.

Defense Department officials, who make the wage adjustment for all blue collar workers here, are now trying to figure out who is owed money from Oct. 1 of this year before they can establish the average raise due to go into effect Sunday. They hope to have it figured out within a couple of weeks. But whenever it is paid, the raise, or raises, will be retroactive.