In February 2001, the U.S. Supreme Court upheld the
EPA’s designation of 0.08 ppm measured as the maxi-
mum daily 8-hour average concentrations as the primary
and secondary standard; the State of Michigan will be
required to comply with this standard. Designation of
nonattainment of the standard is scheduled to begin in
April 2004 . State Implementation Plans (SIPs) required
by the U.S. EPA from all states with nonattainment areas
describing how the state will achieve and remain in
attainment of the NAAQS will be due three years after
designation occurs. The MDEQ analyzed three years of
recent data to project the impact of this standard.
Results show that counties in and downwind of Detroit
typically record values greater than 0.08 ppm (as re-
corded for the fourth highest 8-hour O concentration)
(Ref. 35). Thus, it is anticipated that the Greater Detroit
Carbon Monoxide (CO)
region may be found in nonattainment for ozone in the
There are seven stations monitoring CO in the
Figure 1, produced by MDEQ shows the influence of
Greater Detroit Area; Warren, Oak Park, Allen Park,
meteorological conditions, specifically the link between
Linwood, Livonia, Joy Road, Penobscot Bldg-Down-
elevated ambient temperatures and number of days with 8-
town (monitoring at this latter site ceased after 2000).
hour O levels greater than 0.08 ppm (1980-2001). As high
levels of ozone are often associated with higher tempera-
Under the National Air Quality Monitoring require-
tures, the impacts of ozone, particularly health impacts,
ments, all MSAs with populations greater than 500,000
would typically be greatest during the summer months.
are required to maintain two stations for CO monitor-
ing; one to monitor peak concentrations in major
Figure 2, a map of Michigan counties, illustrates the
traffic locations (the W. Fort site; however, no data
maximum 8-hour averages for ozone based on 1995 data.
available from MDEQ); the other located in a highly
Macomb, Wayne, and Oakland would all exceed the
populated area to measure the community’s exposure
NAAQS of 0.080 ppm. St. Clair County, which represents
(the Joy Road site).
Port Huron, would also be well above the pending standard.