Site

State

PM AQI* (ug/m3)

Libby Courthouse

MT

29

Lewiston

ID

21

Seeley Elementary School

MT

17

Pinehurst

ID

12

Rossiter Pump House

MT

12

Bismarck Residential

ND

11

St. Maries

ID

11

Hannover

ND

11

Miles City

MT

10

Pioneer Park

MT

9