Texas-based Encina plans to build a plant on the Susquehanna River in Point Township, Northumberland County.

Environmental groups and researchers want to establish a baseline for the small pieces of plastic, so they can tell if nurdles are getting into the river from the massive plant.

Sherri Mason said policymakers ask how much of plastic pollution comes from bags or bottles — and she can’t answer. So she’s working to find out.

The move comes as the city of Philadelphia seriously considers a ban on single-use plastic bags.