The Dean Foods/Land O’Lakes plant in Thief River Falls will close later this year. Production and Cooler Manager Larry Amundson confirms the closing date will be between September 1 and October 15. This will affect about 45 of the 110 employees. The distribution center will remain open. Amundson says the company is striving to improve plant efficiency. Instead of operating three plants at less than full capacity, the milk volume now going to Thief River Falls will be transferred to Bismarck and Woodbury.