U.S. District Judge Charles R. Richey yesterday ordered a black engineer for the Navy Department to pay $248.65 to the federal government for costs the government incurred in defending a race discrimination suit he filed and lost.

The ruling is believed to be the first time a federal employee has been forced to pay the costs of a bias case, which, in the case decided yesterday, involved witness fees, the cost of taking pretrial testimony and the cost of filing certain documents.

A week ago, U.S. District Judge John H. Pratt ordered another plaintiff in a race and sex discrimination case to pay the as-yet-undetermined attorney's fees for government lawyers who successfully defended against that claim - which Pratt described as frivolous.

However, Richey's ruling came under a different theory that did not include attorney's fees. It merely applied what Richey said was the law that the government can recover its costs in successful court cases despite the merits of the claims.

Richey's ruling involved the case of Charles Thomas, 41, & GS-14 engineer with the Naval Air System Command Headquarters in Crystal City. Thomas claimed he was denied a promotion to GS-15 became of his race.

Richey found last March that Thomas did not prove discrimination. The judge did find that some NA-VAIR employees made comments about black employees "that demonstrate we have a long way to go in our society to uproot the last vestiges of race and sex prejudice, which does unfortunately still exists in our society and on our governmental offices."

Richey said in his March opinion that he believed the agency "will be the better as a result of this case," but that Thomas' specific claim of bias was unfounded.

Assistant U.S. Attorney Stephen S. Cowen of the Civil division filed papers in court indicating the actual costs to the government for defending the case were $409.50. He said the government would not press for the full amount because Thomas was already heavily in debt for legal expenses in connection with the case.

Richey commended the U.S. Attorney's Office here for being "compassionate and candid" in agreeing to a reduction of the cost award against Thomas. He said Cowen was "a credit . . . to the U.S. government" for taking that position.