Helper 4 with SDP40 290 and SD45’s 321, 328, and 331, and Helper 1 with SD70ACe’s 4310, 4313, and 4300 sit on the set out track. The helpers will spend the day on the set out track while a work window has Mullan Pass shut down. Helper 4 was the mid-train helper on the H-KCKPAS. Helper 1 powered the main part of BNSF coal train C-BKMSPB1-30 as the lead units while Helper 2 (another set of three SD70ACe’s) worked as the rear helper.
The EMD SD (special duty) series are a strong and reliable kind of locomotive which still serve America's rails today. They have proved themselves reliable by clocking in several million miles of freight service over several decades.