Site

State

PM AQI* (ug/m3)

Laredo C313

TX

22

Shuttlesworth

AL

21

Mission C43

TX

20

San Antonio Old Hwy90 C677

TX

18

Brownsville C80

TM

17

Tallahassee Community College

FL

17

Hinds CC

MS

16

San Antonio Northwest C23

TX

16

Austin Webberville Road C171

TX

16

Seiling

OK

15