The Yakima - has just a few non-ethanol gas station left. Check the www.pure-gas.org website to make sure which stations are still on the list. In the state of Washington if a station sells gas with ethanol their gas pumps (it is law) must have a sticker on them saying it contains ethanol.
Two listed in Yakima.
Sharp's Conoco, 208 E Moxee Avenue, Moxee WA
Apple Valley fuel, 920 N 6th Ave, Yakima WA (7:30AM-5:00PM M-F)
Richland & Kennewick show about 4 each - check out pure-gas.org for the different locations.