The contractor performing upgrades to the town’s wastewater pollution control facility is preparing to ask for a time extension, but the new phosphorus removal system is slated to be up and running by the state’s April deadline, town officials said. Upgrades to the water pollution control facility, 155 John St., have been in the works since 2011, when the state Department of Energy and Environmental Protection introduced stricter phosphorus discharge regulations. Neil Amwake, Water and Sewer Divisions general manager, said during a Public Utilities Commission meeting last month that C.H. Nickerson, a Torrington-based environmental construction firm, is preparing a time extension change order. Currently, the construction completion is slated for Feb. 17, but things like paving won’t be finished before the spring, Amwake said. The total cost of the entire upgrade project is $86 million. State grants and low interest loans have been applied to the phosphorus removal system.