MARBLEHEAD-The town has chosen the Concord Square Planning and Development Group of Boston to perform a $40,000 study of Smart Growth.On the recommendation of the Smart Growth Committee the selectmen awarded a contract to the Concord Square group to study the implementation of Chapter 40R, a state law that some town officials suspect to be a viable alternative to Chapter 40B.The committee told selectmen that three applicants responded to the committee’s request for proposals. One was withdrawn and the committee chose Concord Square over Horsely Witten Group of Sandwich and Newburyport.Chapter 40R emphasizes mixing land uses. The town has several mixed-use buildings already – stores on the first floor, apartments upstairs – and Town Planner Rebecca Curran and the Smart Growth Committee are looking at it as a way of increasing the town’s relatively small amount of affordable housing.Curran serves on the committee ex officio and has said that 6.2 percent of Marblehead’s housing stock is “affordable.” That’s 543 units short of the 10 percent the state requires to exempt the town from Chapter 40B projects.Chapter 40R offers four incentives to communities that pursue Smart Growth, including additional incentive payments if the town uses the law to create new housing units. The incentive payments are $75,000 for 22-100 units and $200,000 for 101-200 units. There is also a bonus of $3,000 per unit when building permits are issued, and a priority on state capital funding for any needed improvements and a payment for school costs for any school-age children living in the new units.Committee members include Chairman Gordon King, Dirk Isbrandtsen, Kurt James, Judy Jacobi, William Woodfin, David Stern, Don Morgan and Michael McCloskey.The committee has said that public hearings will be held throughout the process to hear from interested parties and a page on the town website will be devoted to the process.Study findings will be publicized.Like any Zoning Bylaw changes, the establishment of a Chapter 40R District in Marblehead will have to be approved at Town Meeting.