Sal Lupoli has always thought big. Now the Chelmsford restaurateur and real-estate entrepreneur must think big, fast and out of the box.

A major mixed-use development at the long underutilized mill building next to the Gallagher Terminal was approved by the Planning Board Wednesday, passing a key hurdle.

Sal Lupoli is sold on the future of the Merrimack Valley real estate market. The founder of the Sal’s Pizza and Salvatore’s restaurant chains has cooked up a second career as a real estate developer, restoring the massive Riverwalk mill complex in Lawrence into a multitenant office and medical complex.

Developer Sal Lupoli is hoping city regulators fast-track his Thorndike Exchange mill renovation project so he can offer housing to dozens of residents facing eviction from Perkins Place apartments, which was purchased by UMass Lowell in June for student housing.

Plans to dramatically remake the old Comfort Furniture and Bedding building on Thorn-dike Street have been formally submitted to the city, with the first public hearing set for next month.

Cambridge College announced the college has signed an 8,300 SF lease at 280 Merrimack Street in Lawrence. The building is owned by Lupoli Companies’ Riverwalk Properties. During lease negotiations, Cambridge College was represented by Jeffrey Moore and Ken Oppenheim of Lincoln Property Company.

A long-dilapidated mill at a major gateway to the city would become an iconic building with dozens of new apartments and several restaurants, developer Sal Lupoli told the Planning Board Monday in the first look the public got at the project.

Entrepreneur Sal Lupoli inspired more than 100 area business leaders with vignettes from his years in food industry, real estate development and business as part of the Lowell General Hospital Business Leadership Forum this month.