According to an article by David Danelski in the Riverside California Press Enterprise, http://www.presstelegram.com/article/20161002/NEWS/161009932, smog is getting worse in Southern California but there is no consensus on what if any additional measure's should be instituted to fix the situation.
One proposal is for Congress to create a fund, akin to the "Superfund" under CERCLA for polluted land and water contamination clean up, to fund air clean-up measures. Another proposal is for appropriate government entities at the State and Local levels to enact vehicle registration surcharges to raise such funding.
Neither proposal, according to the article, has generated much favorable interest. There has been no movement in Congress on the special fund proposal; and both a Republican Assembly Member and the Democratic head of the State Senate have denounced the surcharge proposal, saying the surcharge would put an unfair additional burden on the public.
The Democratic leader adds that the "polluters' should pay to clean up their pollution. A superficially attractive thought. However, the leader fails to take into account that companies who are fined or otherwise charged for creating pollution are not natural person who would be hurt personally by such impositions; rather, these entities are fictional persons who would do everything possible to pass those charges on to consumers--the very public that politicians claim they want to protect from such higher costs.
The proper question is whether, if we want to increase regulation of air-pollution control, the cost of the regulation should be imposed on the entre public or on the consumers who use the "polluters'" products. That inquiry requires a much more sophisticated analysis than our politicians are likely to provide.