An important part of this discussion must be how successful the EPA has been in implementing the current ozone standard of 75 ppb set in 2008. If many areas of the country are not in compliance, or as the EPA puts it, in non-attainment, then it becomes questionable whether we should be pursuing a stricter standard. We need to attain the current standard first before moving to something stricter. On the hand hand, if EPA has acheived the current standard in most places, then perhaps it is time to attempt something more ambitious.
The answer to this question might be ambiguous. Take a look at EPA’s web page Classifications of 8-Hour Ozone (2008) Nonattainment Areas which you can view by clicking here. This web page lists areas in non-attainment in five categories: extreme, severe 15, serious, moderate, and marginal. The areas in the first three categories are all in California. Two non-California areas are in the moderate category: Baltimore and Dallas/Ft. Worth. Where ozone problems exist outside of California, they are nearly all in the least severe category, the marginal category.
This information is displayed graphically on a map, which you can view by clicking here. Large areas of California have a particularly severe ozone problem. Otherwise, mild-to-moderate ozone non-attainment is concentrated on the Northeast Corridor and many major metropolitan areas: Buffalo, Pittsburgh, Cleveland, Columbus, Cincinnatti, Chicago, St. Louis, Charlotte, Knoxville, Atlanta, Memphis, Baton Rouge, Houston, Dallas, Denver, Phoenix, and the Upper Green River Basin area in Wyoming. Ground-level ozone, not surprisingly, is a problem of cities. Even so, most cities are in the marginal category, which indicates if just a little more was done to reduce ozone in these cities, they would attain the 75 ppb standard.
So an argument can be made both ways. One can argue that more work needs to be done to reach the 75 ppb standard before we attempt something more ambitious, or one can argue that we have nearly attained the 75 ppb standard (except for California) and that it is time to work towards saving even more lives.
In my next post, I will present my own conclusions and recommendations, which you are free to accept or reject.