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