United Refining's Warren, PA facility has made recent modifications to reduce its sulfur dioxide emissions by 62 percent from 2011 levels, the Pennsylvania Department of Environmental Protection (DEP) and United Refining Company announced Thursday.

The modifications, which were initiated by United Reining, are now part of an agreement signed by the company and DEP. It has been sent to the Environmental Protection Agency (EPA) and is currently under review.

The agreement is part of the state's efforts to bring Conewango Township, Glade Township and the City of Warren into compliance with federal air emissions standards.

The DEP hopes to demonstrate these areas are in compliance with the ambient air standard in 2018 after three years of required testing. Sulfur dioxide levels have been well below the standard 75 parts per billion following the reductions made by United Refining in 2015.

The agreement allows the new limits to be legally enforceable. It imposes daily penalties on United Refining if the air emissions do not meet the limits agreed upon.

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