Pleas to drivers to reduce pollution by limiting car trips failed to keep smog at acceptable levels in the San Joaquin Valley, meaning the first region in the nation to be fined under federal clean air laws will face penalties until at least 2013.
The valley, a geographical bowl, was polluted by millions of vehicles, thousands of tractors and hundreds of dairies with noxious emissions Thursday that baked under triple-digit temperatures amid a low-pressure system that stilled wind from the Pacific Ocean.
“It was the perfect storm of both temperature and meteorological conditions, said Sayed Sadriden, executive director of the San Joaquin Valley Air Pollution Control District.
The federal Clean Air Act says the maximum ozone level recorded in an area cannot exceed 125 parts per billion. The eight-hour average level is 75 and the subject of debate since the Obama administration — worried that anti-pollution measures could slow factory work during the economic slowdown — declined this month to lower it to a level some scientists agree is healthy.
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For the $29 million federal penalty imposed on the valley to be removed, no monitoring station can exceed the ozone standard more than three times in three years. Last week’s violation means the earliest the fine can be lifted is 2013, if no more readings exceed the limit.
The recording of 154 parts per billion Thursday occurred in Clovis, east of Fresno in the central part of the valley.
Normally the highest smog levels are recorded farther south near Bakersfield because of prevailing winds that blow from San Francisco to the southeast and trap pollutants against the Tehachapi Mountains.
On Thursday, however, a rare weather phenomenon recently described as the “Fresno Eddy” created a swirl of counterclockwise wind between Bakersfield and Clovis. Pollutants at the southern tip of the valley rode the eddy to a point east of Fresno where the violation occurred.
“It happens a few times a year,” Sadriden said. “Unfortunately, (Thursday) was one of those days.”
The agricultural region has flirted with an ozone violation since schools opened in late August and harvest season kicked into high gear.
Local air-quality regulators had launched a media campaign hoping to persuade drivers to reduce car trips and limit idling to get out from under the $29 million annual fine, most of which will be paid as a $12 fee added to vehicle registrations.
The valley never has gone a full calendar year under the federal ozone limit, but this marked the latest date that a violation has occurred.
Officials were especially disheartened because a break in the triple-digit heat was expected Saturday, and ozone levels could drop next week.
“We fell two days short of making it, so it’s disappointing in that respect,” Sadriden said. “But this is the latest we’ve come in history, so that’s good.”
The valley in recent years has reduced emissions at factories and on farms, but continues to deal with smog because pollution generated as far north as San Francisco is sucked into the bowl.
The toxin in question is ground-level ozone, the ingredient that forms smog. In the high atmosphere it protects the Earth from harmful rays, but at ground level it can blister lungs like a sunburn affects skin.
Ozone is created when car emissions and fumes from solvents react under heat and sunlight.