California's freakishly dry 2013-14 winter dealt the San Joaquin Valley more than a crippling blow to the farm economy.
It set the stage for a lung-scarring siege of soot that squashed any hope of making a key federal air standard.
In December and January, the worst episode of stagnant air in 15 years settled over the region, especially in Bakersfield, says the San Joaquin Valley Air Pollution Control District. The air became a smothering blanket of soot and other microscopic debris.
The particles, known as PM-2.5, are a health nightmare, triggering heart disease and lung illnesses, including asthma and bronchitis. This cold-weather pollutant causes far more premature deaths than summertime ozone, health researchers say.
The California Air Resources Board, the state's air-quality enforcement agency, says hundreds of Valley lives would be saved every year if the PM-2.5 standard was achieved here.
But after last winter, the Valley doesn't have a chance of making the 2015 deadline for the federal standard. It wouldn't make the standard even if the worst hot spots recorded no specks whatsoever, said Jessi Fierro, assistant legal counsel for the district.
"The punchline is you'd need a negative 67 at one monitor in Bakersfield," she said. "You can't go below zero, obviously. So we need more time to make the standard."
The district's governing board this month asked the U.S. Environmental Protection Agency to postpone the deadline until 2019.
EPA officials say they expect to announce their answer soon, adding that they know the Valley faces big challenges with surrounding mountains and stagnant conditions trapping dirty air.
The Valley's biggest PM-2.5 problems are soot from fireplaces and diesel engines. Other tiny specks form when ammonia from dairies combines with oxides of nitrogen from trucks and cars, creating ammonium nitrate.
Over the last five years, the U.S. Department of Agriculture has poured more than $100 million into incentives for farmers to replace dirty diesel engines on their tractors and other equipment. Millions of dollars in state and federal funds also are being spent to help clean up diesel truck fleets.
Kerry Drake, an associate director in EPA's San Francisco regional office, said the federal agencies will continue investing in the Valley and California.
"Our goal is healthy air for the people of the San Joaquin Valley," he said.
Support for the standard
But postponing a standard has touched a nerve among environmentalists who don't think the air district pushes hard enough to clean up pollution.
Activist Tom Frantz of Shafter in Kern County says if EPA allows the deadline extension, it will be a death sentence for hundreds of residents.
He said district leaders should be tougher on oil producers, dairies, biomass incinerators, distribution centers and urban sprawl. The deadline should remain the same, and more urgency should be encouraged, he said.
"They are trying to delay tighter regulations at the expense of human health," he said.
If the district misses the 2015 deadline, more restrictive regulations would be required to avoid federal sanctions, which could include higher expenses for businesses locating in the Valley or the temporary loss of road-building money.
Air district leaders say they have some of the toughest rules in the country. The latest update on the residential wood-burning rule is projected to remove more than 5 tons of soot daily from the winter air. That reduction is several times higher than most rules these days.
But the Valley still won't attain the PM-2.5 standard by the deadline next year, officials say.
The daily federal health standard for PM-2.5 is an average of 35.4 micrograms per cubic meter of air. Thirty or 40 of these specks would fit side by side across the width of a human hair.
Between 2012 and 2013, PM-2.5 increased at every Valley monitor -- more than doubling at one monitor on Planz Road in Bakersfield. Because no storms were coming through the Valley for two months, pollution hung around and accumulated.
But why wouldn't the Valley be in attainment if pollution simply dropped below the standard next year? That's not the way this complicated federal law works.
A monitor must have a three-year average of less than 35.4 micrograms. The law requires one of the worst readings of each year in the calculation.
At Planz Road, the number jumped from 40.6 microns in 2012 to 96.7 in 2013. Even with a zero this winter, the three-year average would still be more than 45.
The end of the drought would not mean the end of the problem, air officials said. The Valley usually has episodes of stagnant winter weather, and the EPA could further tighten the standard by lowering the amount of daily particle pollution allowed.
In any event, the district will have to continue reviewing rules and recommending changes, officials said. That could include further restrictions on residential wood burning.
Other smaller sources of PM-2.5, such as restaurant charbroiling and commercial yard-care equipment, also would be reviewed.
The Valley is one of the country's worst-polluted basins, and many rules already are on the cutting edge, district leaders said. But even the smallest pollution sources are becoming important now.
"We need the extension," Fierro said. "The natural challenges and the legal challenges make this very hard."