With mail tucked into his waistband and a container of tomato vegetable soup in his hand, Dave Carstairs maneuvered along the sidewalks and crosswalks on a weekday of light traffic and low humidity.

Since signing a purchase of sale agreement for a 95-acre parcel behind the Monitor building, Kevin Lacasse, CEO of New England Family Housing, has gotten to work.

Early plans to develop a 95-acre parcel of land along the Merrimack River would include more than 600 units of housing in a mixed-use project along Interstate-93 and the railroad, north of the Concord Monitor building.