I can sum its current ops up in one word: non-existent.

DL abandoned Portland long ago. It's amazing there are still DL domestic flights out of there.

Do a search here in the DL Forum; it may be your best source of information.

In addition to the economic downturn that the nation suffered at the turn of the decade, PDX had a reputation for having some of the worst INS employees in the US. This distinction earned the city the nickname Deportland. These two factors probably are what killed off DL's operations out of PDX.