Red Shield Environmental, which bought the mill, began re-starting the pulp machines on Monday. Now a total of 175 former GP workers are back on site.
Some of the pulp now being produced will help feed University of Maine-based technology to turn wood into fuel or plastics.
The 50-million dollar wood-ethanol plant will take about two years build, but the chairman of Red Shield says other jobs will be added to the Old Town facility between now and then.
More than 450-workers lost their jobs when Georgia-Pacific pulled out of town more than a year ago. Red Shield re-opened the facility in november, hiring 55-employees to start up the biomass boiler.
The boiler now heats the facility and is expected to provide power to other companies that move on site.