Located in the main stairwell landing between the 2nd and 3rd floors.  Next to the flags is a Puyallup Tribal language yard sign by Taylor Dean which says "didiʔɫ čəɫ ʔa" meaning "We are still here."

I emailed (12/1/21) Charlotte Basch, Historic Preservation Coordinator,  from the Puyallup Tribe Historic Preservation Office to see if she could point me in the direction of finding information about the symbols on the tribal flag. Here is her response, 

“This is a great question! I don’t have anything official drafted on this right now, but we are hoping to highlight this as a future Facebook post.

In short, the flag has two major symbols from Puyallup culture—təqʷuʔma [“Taquoma” or Mt. Tacoma instead of "Mt. Rainier"] and Thunderbird. Do you have a copy of Marian Smith’s The Puyallup Nisqually?  On page 70 there’s a reference to thunder that gives some insight to the connection between thunder, Thunderbird, and Puyallup. In order to really understand this explanation, though, it’d be good to have familiarity with the concept of powers—spiritual strengths individuals could receive through ceremony and/or individual contributions to community.

“The thunder was a bird…When it opened its mouth, sparks came out and these were lightning or flint. When it dashed through the air, it made thunder. It lived in a crater near Mt. Rainier on the north side of the ridge…The Puyallup were famous for their thunder power and when it thundered other people would say, ‘that is Puyallup power.’”

More simply though, I would share that the two symbols (thunder/Thunderbird and the Mountain) are central to Puyallup identity and culture—both being some of the most powerful and prominent features in the surrounding area, which is easy for non-Native residents today to understand. The Thunderbird made its nest in the Mountain, contributing to the Mountain’s physical and spiritual danger. Puyallup people understood the power of these beings, and as such regarded them both with the highest respect.”