2004FOUR HIGHEST MAXIMUM EIGHT-HOUR OZONE AVERAGES BY MONITOR
Based on Information Received by East-West Gateway Measured in Parts Per Billion
Location
First Highest
Second Highest
Third Highest
Fourth Highest
Missouri Monitors - April 1-October 31, 2004
Arnold
80
74
73
70
Orchard Farm
81
77
77
77
West Alton
80
80
78
76
Queeny Park
75
69
67
67
Breckenridge Hills
72
71
70
69
Ferguson
69
69
68
68
Ladue
72
69
68
67
Sunset Hills
76
73
72
70
Clark (St. Louis)
62
59
58
58
Margaretta (St. Louis)
77
74
73
72
Bonne Terre*
73
71
71
70
Illinois Monitors - May 1-September 30, 2004
Edwardsville
76
75
68
68
Wood River
81
80
73
73
Maryville
82
81
80
78
Alton
80
74
74
74
East St. Louis
78
76
75
73
Jerseyville
77
76
75
73
Nilwood*
80
69
68
67
Houston*
69
66
65
64
* Monitors outside the St. Louis eight-hour ozone non-attainment area Eight-hour ozone standard is 85 parts per billion (ppb)
Excursions of the standard are in bold
To attain the eight-hour ozone standard, the three year average of the annual fourth highest daily maximum eight-hour ozone concentration as measured at each
monitor has to be less than or equal to 85 ppb.
Source - Missouri Department of Natural Resources and the Illinois Environmental Protection Agency. Information is preliminary and has not been quality
assured.
East-West Gateway Council of Governments
One Memorial Dr., Ste 1600 St. Louis, MO 63102 phone: (314) 421-4220 or (618) 274-2750 fax: (314) 231-6120 e-mail: webmaster@ewgateway.org
