The Arlington County Board, which has placed a priority on retaining supermarkets in the rapidly urbanizing county, has cleared the way for Safeway Stores Inc. to replace its Cherrydale store with a larger, more modern facility.

The board agreed at its meeting last Saturday to rezone a 6,373-square-foot tract on N. Monroe Street behind the existing Cherrydale store on Lee Highway from a residential to a low-rise commercial classification. The rezoning had been delayed while Safeway negotiated to purchase the land.

The rezoning was necessary for the project because the county code bars using residential property for access to commercial property. Safeway plans to use the tract for access to its parking lot and loading dock.

A new 41,000-square-foot store would replace the current 28,000-square-foot market, and would include a pharmacy, delicatessen, bakery, expanded seafood department and flower shop. The old store is to continue operating while the new one is built. Construction is scheduled to begin in August and be completed next spring.

The pharmacy is expected to fill the gap in the Cherrydale and Maywood neighborhoods, which have been without a drugstore since the old Drug Fair a block away on Lee Highway closed a few years ago.

Although the fate of the Safeway store in Rosslyn has been in doubt for several months, Barbara Ettinger, a Safeway spokeswoman, said the grocery chain did not expect to close the Cherrydale store if the rezoning had not been approved.

Ettinger said earlier this week that Safeway is still negotiating with the Kaempfer Co., developers of a planned 12-story office building at the Wilson Boulevard site of the Rosslyn Safeway, and expects to be incorporated in the new building.