Union raises safety concerns about refinery Marathon Petroleum is disputing issues raised by several labor unions about potential safety lapses at their St. Paul Park refinery Author: John Croman Updated: 9:27 PM CDT April 27, 2021 ST PAUL PARK, Minn. — Union workers who've been locked out of the Marathon Refinery in the south metro suburb since January say they're worried about potential safety hazards. In fact, a group of labor unions issued a report this week, sounding the alarm about replacement workers' lack of knowledge and experience. Marathon says the St. Paul Park plant is operating safely, and the unions are off base with their criticism of how safety protocols are being enforced on the site. It comes as talks have stalled between the Ohio-based petroleum company and Teamsters Local 120.