Selectmen will hold a public hearing Monday night to consider whether to pursue a state grant to help underwrite the cost of improvements to River Road West. The work would entail building a roundabout and turning lanes on the road to accommodate a planned mixed-use retail and residential project, said Jon Weaver, a project manager for Worcester Business Development Corporation, a nonprofit organization performing consulting work on the project. The public hearing begins at 7:30 p.m. in the Municipal Building.