An administrative law judge with the Merit Systems Protection Board has issued an "initial decision" reinstating a Labor Department employe fired by Secretary Raymond J. Donovan for alleged misconduct involving hiring and travel practices.

But Judge Edward J. Reidy said he found no evidence to support Curtis A. Foster's contention that his firing was politically motivated or prompted by pressure from the owners of the Adolph Coors Co.

Foster, who also would be awarded back pay by Reidy's decision, was dismissed from his Senior Executive Service position in early 1982.

At the time, Foster charged that he was the victim of political discrimination stemming from his attempts as regional director of the Occupational Safety and Health Administration to conduct health and safety inspections in a Coors brewery in Golden, Colo.

Foster had charged that Joseph and William Coors used their close ties to the Reagan administration to coax Labor officials to fire him.

While finding no evidence to support that charge, Reidy nevertheless said Foster was discharged improperly. The decisions Foster made regarding the hiring of four construction inspectors and his handling of travel funds for the four men were in the agency's interest, Reidy said.

The decision becomes final unless a petition for review is filed within 35 days or the full board reopens the case.