After six years, dirt is flying at Merrimack Premium Outlets.

Town and state officials joined the project developers last week to celebrate the formal groundbreaking of the 130-store outlet mall now under construction on Industrial Drive.

The $100 million project, first proposed in 2004, received final approval in 2008 after years of contentious debate. But developers, delayed by further planning and logistics, are just now setting to work clearing the 170-acre property, near Exit 10 of the F.E. Everett Turnpike.

Construction crews will conduct site work through the winter and much of the spring, and they could start to erect buildings by the summertime, according to Mark Silvestri, executive vice president of Premium Outlets, a division of the Simon Property Group.

The project will create more than 800 jobs during construction, and when it’s complete, likely in 2012, it will add another 800 full- and part-time service jobs, according to Simon figures.

The first phase will consist of 100 clothing, home-good and other retail stores, with other additions to follow.

In total, the center is projected to generate more than $140 million in retail sales each year, as well as more than $1 million annually in property taxes.

“We’re here today to celebrate change,” Tom Koenig, chairman of the Town Council, told the crowd that gathered for Wednesday’s ceremony. “Merrimack Premium Outlets is coming to Merrimack, bringing change. …This change gives us a chance to grow our community.”

– JAKE BERRY