Some ramps along the San Bernardino Freeway from Fremont Avenue to Rosemead Boulevard will be closed beginning next week as part of a $1.6-million rehabilitation project, according to Heinz Heckeroth, district director of the California Department of Transportation. The ramps will be closed at alternating interchanges, beginning with the eastbound ramps. For example, beginning Tuesday, the Fremont and Garfield Avenue ramps will be closed, but the Atlantic Boulevard and New Avenue ramps will remain open. Crews will work along the eastbound side between 5:30 a.m. and 2 p.m. weekdays until mid-July and return westbound from 9 a.m. to 3 p.m. through late August. Each ramp will close for about 10 days while workers repave the surface, widen the shoulders and lengthen the merging areas, Heckeroth said. Work is expected to be completed in March, 1986. Griffith Co. of Long Beach has the contract.