BNSF 1653 is a former BN unit which, until recently, wore the Cascade Green colors, just like her sister unit BNSF 1652. Soon there will likely be no BN flagged units running in the Denver Yard - eventually they will all get painted into the Heritage III scheme.
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.