A federal mediator has called Allina Health and the Minnesota Nurses Association (MNA) back to the bargaining table in a late attempt to avoid 4,800 nurses striking beginning on Labor Day, according to the Minneapolis Star-Tribune.

The MNA has given a 10-day notice of intent to strike beginning at 7 a.m. on Sept. 5. It would be the second strike by the nurses this year after a one-week walkout in June, and this time, there wouldn’t be a set date for the nurses to return to work.

“This is an open-ended strike,” said MNA Executive Director Rose Roach. “These nurses have never felt more disrespected and more devalued by this employer in their entire careers. They are mad.”

The MNA has argued against Allina’s contract terms to end union-backed health plans and save an estimated $10 million by moving nurses to its corporate benefit plans. Allina has argued the corporate plan is still a generous insurance package, and said the MNA’s counterproposal would be “unfair” to other employees and ignored the system’s cost concerns.

“Allina Health nurses currently have access to four extra health plans, which were first introduced in the early 1990s,” Allina said about the negotiations. “Back then, it was typical that people paid their monthly premium and not much for the cost of the care they received. As health care costs have skyrocketed over the years, so too have the costs of these nurse-only plans.”

The Associated Press reported Allina expects the MNA to offer another counterproposal when the two sides meet again Sept. 2.

If the nurses go ahead with the strike, it would affect five Minnesota hospitals: United Hospital in St. Paul, Mercy Hospital in Coon Rapids, Unity Hospital in Fridley and Abbott Northwestern Hospital and the Phillips Eye Institute in Minneapolis. Allina has said it's recruiting temporary nurses to make key medical services available during any walkout.