2.2.1
Criteria Air pollutants
Nitrogen Dioxide (NO )
2
During 2001, Detroitís NO  monitoring sites at Linwood
Sulphur Dioxide (SO )
2
2
and E. Seven Mile Road measured annual mean concen-
trations of  0.023 ppm and 0.019 ppm, respectively.  The
There are seven monitoring stations for SO  within the
2
annual mean NAAQS for NO  is 0.053 ppm.  The highest
2
Primary Metropolitan Statistical Area (PMSA).  During
annual mean value occurred at Detroitís Linwood site in
the year 2000, Detroitís W. Fort Street site shared (with
both 2000 and 2001; the annual arithmetic means were
the Port Huron monitoring station) the highest annual
0.025 ppm and 0.023 ppm, respectively.  Although there is
average for SO  in the state, with an annual average of
2
no hourly NAAQS, the maximum 1-hour concentrations
0.007 ppm.  This remains below the annual NAAQS of
also occurred at Linwood during 2000 and 2001; the
0.03 ppm.
maximum hourly concentrations were 0.128 ppm and
0.194 ppm, respectively.  Trends (1992-2001) show the
In 2000 and 2001, the highest 24-hour concentration of
Detroit PMSA average annual NO  level at about 0.02
2
SO  within the state of  Michigan occurred at the Detroit
2
ppm, which is comparable to the historical nationwide
W. Fort monitoring site (Ref. 32).  The W.Fort Site is a
average.
National Air Monitoring Station (NAMS) site situated to
levels (Ref. 33).  The W.
monitor  maximum SO
Ozone (O )
2
3
Jefferson site also measured high concentrations,
Monitoring of  ozone levels occurs at six sites within the
although both sites were still below the 24-hour NAAQS
3
Detroit PMSA; three located in Wayne County (E. Seven
(0.14 ppm or 365 µg/m ).  For both years, the Linwood
Mile Rd., Linwood, Allen Park); two located within
site had high 3-hour concentration measurements; again
Macomb County (New Haven and Warren); and one
these concentrations were well below the 3-hour second-
located within Oakland County (Oak Park).
ary NAAQS (0.50 ppm).
Maximum O  concentrations typically occur downwind
Total Reduced Sulphur (TRS)
3
from metropolitan areas that produce the precursor
emissions (Ref. 34).  Monitoring sites meant to detect
Unlike Ontario, TRS is not routinely measured in
concentration(s) are typically located 10-30
maximum O
Michigan.
3
miles downwind from an urban area.  For this reason,
rural areas can, on occasion, detect higher O  concentra-
3
tions when compared to urban or suburban sites.
TABLE 24
Year 2000 and 2001 Summary of  SO  Data for Greater Detroit Area
2
3
Primary NAAQS
Annual Arithmetic Mean
0.03  ppm (80 µg/m )
3
)
24-hour
0.14 ppm (365 µg/m
3
)
Secondary NAAQS
3-hour
0.50 ppm (1300 µg/m
Station
2000 (all values in ppm)
2001 (all values in ppm)
Annual
Max.
Max
Max
Annual
Max.
Max
Max
Mean
1hr
24hr
3hr
Mean
1hr
24hr
3hr
Values
Values
Values
Values
Values
Values
Warren
0.003
0.078
0.017
0.058
0.002
0.068
0.130
0.042
River Rouge
0.005
0.094
0.019
0.050
0.005
0.075
0.016
0.055
W. Fort
0.007
0.126
0.058
0.088
0.007
0.224
0.045
0.115
Linwood
0.006
0.149
0.030
0.098
0.005
0.209
0.028
0.129
E. Seven Mile
0.005
0.083
0.018
0.052
0.004
0.160
0.020
0.073
W. Jefferson
0.008
0.163
0.046
0.103
0.007
0.126
0.044
0.098
Dearborn
0.007
0.118
0.041
0.078
0.008
0.079
0.032
0.045
33