The U.S. Court of Appeals ruled yesterday that the Labor Department gave "wholly inadequate" reasons for approving the results of last year's controversial Washington Teachers Union election and ordered the department to reexamine its findings.

The election outcome was challenged by James D. Ricks, a former Ballou High School science teacher, who contended that campaign violations by longtime incumbent union president William H. Simons and his supporters prevented Ricks from ousting Simons.

Simons won by 204 votes.

The June 1983 balloting was the third attempt in two years by the union to elect officers. U.S. District Judge Aubrey Robinson Jr., acting at Labor's request, disallowed two earlier elections because of voting irregularities.

Labor is required to review the validity of union elections under a federal law designed to "guarantee internal union democracy."

A three-judge appeals panel disagreed yesterday with six of seven charges by Ricks, including allegations that ballots were improperly mailed and that some ineligible union members were permitted to vote.

But the court said Ricks' claim that improper interference with his distribution of campaign literature might have affected the election outcome was "far more troubling." Labor's statement of its reasons for asking Robinson to override that "well-documented" allegation were "wholly inadequate," the court said.

Robinson declared the voting a "lawful election" last October.

In its ruling, the appeals court said Ricks had supplied affidavits saying his literature was removed from school mailboxes "before the intended recipients had an opportunity to read it . . . . "

"If attributable to the union leadership, such interference constitutes a clear violation of the law and certification of the election would be improper if the infraction 'may have affected the outcome of the election.' "

The opinion said Labor failed to give "even the most cursory statement of the facts" supporting its conclusion that Ricks made inadequate attempts to overcome the alleged violation.

The court also labeled the department's finding that the alleged violation did not affect the election outcome "perfunctory and cryptic."

Ricks' lawyer, Oliver Long, said the election results could be thrown out if Labor cannot substantiate its findings. A Labor spokesman declined to comment. Attempts to reach Simons and Ricks, now a National Education Association employe, were unsuccessful.

The decision was written by Circuit Judge J. Skelly Wright and joined in by Judges Patricia M. Wald and George E. MacKinnon.