ST. PAUL, Minn. (AP) — The public authority overseeing the new Minnesota Vikings stadium and the main contractor building it are headed for a three-day mediation session next month over some disputed costs.

Minnesota Sports Facilities Authority Chairwoman Michele Kelm-Helgen said Wednesday that the commission and Mortenson Construction are going before a mediator starting Nov. 9 to determine who should pay for $15 million in unforeseen costs resulting from changes to the $1 billion project. She told a legislative panel that taxpayers won’t face additional exposure because the public share is capped and a $29 million contingency fund remains available.

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The mediation is private. If it fails the dispute could head for arbitration.

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The stadium is more than 70 percent complete and slated to open next summer. The Vikings are covering about half the costs.

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