North Carolina Counties with 8-Hour Ozone Violations 2005-2007

In March 2008, the US EPA promulgated a revision of the ozone standard with a lower nonattainment threshold. We have colored the Design Value map in a novel way so that it can be compared easily to past years with the previous standard and to future years with the new standard. We present the details in four tables. Table 1 and Table 2 refer to the ozone standard that was effective from 1997 through 2007. Table 3 and Table 4 refer to the ozone standard that was effective beginning in 2008.

Table 1. The following table shows two counties with a 3-year average of the annual 4th high value for each year equaling 0.085 ppm level or higher (violation of the 8-hour standard that was in effect from 1997 through 2007). The first column lists the county; the second lists the average value for that county. On the 2005-2007 Design Value Map, these counties are colored red.

County Average value
Mecklenburg 0.093 ppm
Rowan 0.090 ppm

 

 

 

 

Table 2. The following table shows 29 monitored counties that are attaining the 0.085 ppm standard that was in effect from 1997 through 2007. The first column lists the county; the second lists the average value for that county. On the 2005-2007 Design Value Map, these counties are colored gray and green, with gray signifying counties that would not attain the 2008 8-hour standard.

County Average Value
Alexander 0.079 ppm
Avery 0.070 ppm
Buncombe 0.074 ppm
Caldwell 0.076 ppm
Caswell 0.077 ppm
Chatham 0.074 ppm
Cumberland 0.082 ppm
Davie 0.083 ppm
Durham 0.078 ppm
Edgecombe 0.077 ppm
Forsyth 0.081 ppm
Franklin 0.078 ppm
Graham 0.078 ppm
Granville 0.081 ppm
Guilford 0.082 ppm
Haywood 0.079 ppm
Jackson 0.077 ppm
Johnston 0.076 ppm
Lenoir 0.076 ppm
Lincoln 0.083 ppm
Martin 0.074 ppm
New Hanover 0.072 ppm
Person 0.077 ppm
Pitt 0.077 ppm
Rockingham 0.078 ppm
Swain 0.066 ppm
Union 0.081 ppm
Wake 0.081 ppm
Yancey 0.078 ppm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 3. The following table shows 25 counties with a 3-year average of the annual 4th high value for each year equaling 0.076 ppm level or higher (violation of the 8-hour standard established in 2008). The first column lists the county; the second lists the average value for that county. On the 2005-2007 Design Value Map, these counties are colored red and gray, with red signifying counties that violated the 1997 8-hour standard and gray signifying counties attaining the 1997 8-hour standard.

County Average Value
Alexander 0.079 ppm
Caldwell 0.076 ppm
Caswell 0.077 ppm
Cumberland 0.082 ppm
Davie 0.083 ppm
Durham 0.078 ppm
Edgecombe 0.077 ppm
Forsyth 0.081 ppm
Franklin 0.078 ppm
Graham 0.078 ppm
Granville 0.081 ppm
Guilford 0.082 ppm
Haywood 0.079 ppm
Jackson 0.077 ppm
Johnston 0.076 ppm
Lenoir 0.076 ppm
Lincoln 0.083 ppm
Mecklenburg 0.093 ppm
Person 0.077 ppm
Pitt 0.077 ppm
Rockingham 0.078 ppm
Rowan 0.090 ppm
Union 0.081 ppm
Wake 0.081 ppm
Yancey 0.078 ppm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 4. The following table shows 6 monitored counties that are attaining the 0.076 ppm standard that was established in 2008. The first column lists the county; the second lists the average value for that county. On the 2005-2007 Design Value Map, these counties are colored green.

County Average Value
Avery 0.070 ppm
Buncombe 0.074 ppm
Chatham 0.074 ppm
Martin 0.074 ppm
New Hanover 0.072 ppm
Swain 0.066 ppm

 

 

 

 

 

 

 

 

Note:

  • Additional counties may be involved in emission reduction strategies
  • Nonattainment designations may not follow county boundaries
  • Final data validation is not yet complete