Ground Level Ozone
which occurred at the Port Huron site on May 22, 1996
During the years 1992-2001, the highest detected 1-hour
(MDEQ, 2003).
concentration for all of  Michigan was 0.184 ppm,
O
3
) Values Averaged at 3-year Increments, 1995-2001
TABLE 44
Fourth Highest 8-Hr Ozone (O
3
The proposed USEPA 8-hour standard is met when the 3-year average of  the
th
4  highest concentration is less than or equal to 0.08 ppm.
Station
Values in ppm
1995
1996
1997
1998
1999
2000
2001
th
Port Huron
4  highest 8-hr
0.094
0.086
0.079
0.091
0.091
0.08
0.084
Value
3-yr average
0.089
0.088
0.086
0.085
0.087
0.087
0.085
Rounded to
0.09
0.09
0.09
0.09
0.09
0.09
0.09
0.01 ppm
Source: MDEQ 2003
Although the U.S. EPA has not begun to designate areas
Carbon Monoxide
as nonattainment; Table 44 indicates that should recent
Not Monitored.
circumstances persist, Port Huron would be in non–
attainment with the new ozone standard.
Coarse/Inhalable Particulate Matter (PM )
10
Nitrogen Dioxide (NO )
2
Not Monitored.
Not Monitored.
Fine/Respirable Particulate Matter (PM )
2.5
3
TABLE 45
Annual Mean PM  Concentrations, 1999-2001 (annual mean, rounded to nearest 0.1 µg/m ) -
2.5
3
Annual USEPA PM  Pending/Proposed Annual Standard - 15.0 µg/m )
2.5
Station Name
1999
2000
2001
Mean
Port Huron
13.2
14.4
14
13.9
NOTE: Calculating the Annual arithmetic mean to determine attainment status,
mean concentrations are averaged over three years.
the annual average of  the quarterly PM
2.5
3
This result must be less than or equal to 15 µg/m .  For Port Huron, its calculated annual
3
average is 13.9 µg/m ), which would be in compliance with the new standard.
52