Union Pacific is testing Electro-Motive Diesel’s SD70ACes on the Moffat Tunnel Subdivision west of Denver, Colorado. UP’s mobile laboratory car No. UPP 210 is bracketed by EMD demonstrators Nos. 1206 and 1208 on high-adhesion tests with a westbound West Elk Mine coal empty leaving Rocky and about to enter Big 10 Curve on August 26, 2013.