A reader e-mailed Monday with a familiar comment:

"It has been shown that if all vehicles were to be pulled off the road here in the Valley, we still would not meet the air quality guidelines as so much of the pollution blows into the Valley from the Bay Area.
Yet, what is being done to control this problem at the source?"

Bay Area pollution does come into the Valley, but its contribution to the air problem here is often overstated. Even if nothing came from the Bay Area, the Valley would have big problems.

Does anyone speak up about pollution that blows into the Valley? Yes.

I have heard officials at the San Joaquin Valley Air Pollution Control District argue that the Bay Area should have the same stringent smog controls as Valley residents have. The argument has been successful many times.

There have been federal health violations seven of the last eight days here. Yesterday, the only monitor to show a violation was in Sequoia National Park. I wonder if Bay Area pollution had anything to do with that?