Graves Supermarkets will sell four of its five stores and retain ownership of one store in the company’s home base of Aroostook County, the company announced Wednesday. Graves stores in Bar Harbor and Camden, as well as the shopping plaza where the Camden store is located, will be sold to Scarborough-based Hannaford Bros. Co., according to a written statement about the sales agreements. Dana Edwards, who worked for Hannaford for 30 years and now is director of operations for Graves Supermarkets, has signed a letter of intent to purchase the Graves stores in Hampden and Dover-Foxcroft, the statement indicated. The Graves company, which was founded in Mars Hill in 1935, will keep its store in Presque Isle. Terms of the sales were not disclosed. The deals are expected to close at the end of this year. Hannaford Bros., a subsidiary of Delhaize Group in Brussels, Belgium, employs more than 24,000 workers at the 144 stores it operates in New England and New York. The company plans to offer employment to all workers at the Bar Harbor and Camden stores, according to the release.