WA State MatchBack data from 07.30.2019

Below are WA county return information for 07.30.2019 [source]. Some smaller counties (AS, GA, SM, WK, WT) are not yet reporting. These totals will change daily. Totals as of 07.30.2019:

    CountyCode   Count     Accepted Received Rejected
    Total        4432473   445536   12876     9997

Statewide turnout is still an anemic 10% This statistic assumes all counties and precincts are active for this 2019 Primary election and some counties will only have a partial primary: 

       Statewide Turnout (Accepted/Count)

       (445536/4432473) * 100
        10.052

A quick look at the 10 counties with more than 100K registered status active voters shows Spokane and Whatcom outdistancing other counties in PCT_Accepted ballots. It also shows Benton county with a comparatively high percentage of rejected ballots: 

Column Totals represent:
Count    # 07.17.2017 Status Active Voters
Accepted # Ready for Tabulation (e.g. 'Turnout')
Received # On conveyor belt for Accepted/Rejected
Rejected # Challenged Ballots
PCT_Accepted=round(Accepted/Count,3) * 100 (e.g. Turnout PCT)
PCT_reject = round(Rejected/(Accepted+Received+Rejected),3)* 100)

See here for list of County Codes with map.