The Port of Hood River says roadway asphalt repairs at the Oregon approach and bi-annual bridge deck maintenance welding will prompt several single-lane closures of the Hood River-White Salmon Interstate Bridge this month.  Bridge users should plan for delays or seek alternate routes from Monday at 8 p.m. to Tuesday at 2 a.m. for the asphalt work at the Oregon approach.  Welding crews will be on the bridge for maintenance of its deck the weeks of October 21 and October 28 from 9 a.m. to 3 p.m. each weekday.  Flaggers will direct traffic around the work zones in all cases.  Port officials advise motorists to expect delays and drive slowly for worker safety.