The EPA's plan – also supported by the South Coast Air Quality Management District and the California Air Resources Board – acknowledges that "90 percent of NOx emissions and 60 percent of VOC emissions come from vehicles," and that those contribute to smog and pollution. The four groups say that the problem is that the plan has tremendous loopholes that allow polluters to continue their old habits. The director of the Sierra Club's My Generation Campaign, Evan Gillespie, told the Tribune, "We are extremely disappointed to see this loophole was relied on again in the plan submitted by the air district. We have all the tools at our finger tips to solve this problem. It is really at this point not a technological problem but a political problem."
The "tools" Gillespie referred to include electric cars and "other less-polluting technologies," the Tribune notes. Read more here or listen to an audio report here.