While the "Black Fog of Blossburg" isn't as impressive as it once was, the sight of blue SD40s leading anything over the Continental Divide west of Helena makes for an awe inspiring sight (and sound). Three MRL SD40-2XRs, on lease to BNSF, along with a SD70MAC destined for the Copper City local at Garrison, pull 7913 tons of manifest freight through the tunnel on top of Mullan Pass. This would end up being the last revenue use of the leased power as BNSF ended the horsepower payback requirement these units were used for abruptly and returned the units to MRL.
