Norwich — Workers with Wiese Construction were working on demolishing the 1830 granite mill building Thursday on the Yantic River at the Uncas Leap Heritage Park.

The company, based in Norwich, submitted the low bid of $349,752 for the proposal to remove the roof and upper story of the dilapidated mill building, shore up the exterior first-story walls to create a ruin and stack the granite blocks on site for future use as seating for a proposed amphitheater.

City officials and representatives from the Mohegan Tribe have been working on the plan to create the Uncas Leap Heritage Park for the past several years. The project started coming into form in 2017, when the city used grant money and hired planning consultant Milone & MacBroom to design a master park plan at the 1.4-acre site along Yantic Street adjacent to the falls.

Project planners determined the cost would be prohibitive to try to save the granite mill. Instead, the plan calls for keeping the first-story exterior walls and window openings and creating a walking path through the ruins.