This is the first Amtrak departure from Portland, the first morning train to Seattle. Don't think the trains were named yet, but at the start there were two daily trains between Portland and Seattle, with the tri-weekly train that would become the Coast Starlight in the mid day slot. The first train to depart had a pair of SP&S Fs. The BN 9750 is, I believe the former SP&S F3A 801.
Also in this photo you can see the just arrived UP City of Portland on the left, and I believe that's the last BN 23 (former SP&S 3) on the right.