Prime Tanning Co. said recently that it will close its Berwick plant and transfer operations to its Hartland facility in central Maine. Roughly 150 manufacturing jobs will be lost in Berwick, but the company expects to add about 75 people to handle the increased work in Hartland. Prime Tanning, which has held a central role in Berwick since 1935, blamed the move on skyrocketing energy and chemical costs, and languishing sales. It was said it now costs 20 cents more to produce each foot of leather at Prime, where each foot has an average selling price of $3. That's because the price of fuel oil -the company's top material expense -is up between 40 percent and 50 percent from last November, and suppliers aren't negotiating on the increased cost of chemicals. Prime has spoken to the Maine Department of Labor, said an agency spokesman. Department experts will be in Berwick for rapid-response sessions, worker education on career center offerings, unemployment benefits, health care and other services.