10
Day of Week NOx Emissions from Four Coal-fired Plants near Charlotte
-25
-20
-15
-10
-5
0
5
10
15
20
Sun
Mon
Tue
Wed
Thu
Fri
Sat
Day of Week
Text Box: % Difference from
% Difference from
Text Box: 7-Day Average
 7-Day Average
Allen
Riverbend
Marshall
Buck
From Perry and Owens, AWMA, 2001