ROUNDUP DOT Unit Recommends  
m The Transportation DepartmentÛªs public advocate has urged approval of the merger of Northwest Airlines and Republic Airlines, concluding that travelers will not be harmed by the acquisition, officials said yesterday.</br></br>The proposed purchase by Northwest of Republic for $884 million, which would be the largest merger in U.S. airline history, is still before a department administrative law judge, who must decide whether to recommend approval by June 27. The final decision is up to Transportation Secretary Elizabeth Hanford Dole.</br></br>In papers filed before the law judge, the departmentÛªs ÛÏpublic counselÛ urged approval of the merger and contradicted conclusions reached by the Justice Department, which has opposed the deal on the grounds it would hurt competition.</br></br>While the Public CounselÛªs Office is within the Transportation Department, department spokesman Ed OÛªHara emphasized that the counsel represents only one view and that the administrative law judge might not agree.</br></br>Republic and Northwest compete against each other on 40 routes and carry between them about 80 percent of the passengers board-I ing at Minneapolis. The two airlines also compete extensively through Detroit.