Site

State

PM AQI* (ug/m3)

Badlands

SD

42

Maple Falls-Azure Way

WA

25

St. Maries

ID

24

Shuttlesworth

AL

24

Marysville-7th Ave

WA

23

Rossiter Pump House

MT

23

Nogales Post Office

AZ

23

Portola

CA

21

Pinehurst

ID

21

Colville-E 1st St

WA

20