Two employees of the south Philadelphia oil refinery that caught fire last week have filed a proposed class action lawsuit over the company’s plans to close the facility.

Employees Nathan Rutkowski and Martin Harper filed the lawsuit against Philadelphia Energy Solutions in the U.S. District Court for the Eastern District of Pennsylvania on Friday. According to the 21-page complaint, PES, which operates several refineries in Philadelphia, is expected to lay off more than 1,000 employees July 1.