Features

WHITTIER — Polly Bobadilla’s ride may not have quite the power of her old set of wheels, but she’s happy to be seen driving down the street in it. 

No longer must she endure the noise from her old bus’s diesel engine, or dirty looks from motorists freshly sullied with stinky black exhaust. 

“I don’t have to inhale the fumes or smell all the smoke. And I don’t need to shut the windows,” said Bobadilla, who has driven students in a compressed natural gas-powered bus for about three years. 

That’s an experience regulators and environmentalists want more students and bus drivers to have in California, which despite an array of trailblazing air-pollution rules has more of the oldest, worst-polluting school buses than any other state in the nation. 

About 9 percent of the state’s 24,000 school buses were built before 1977, when federal safety and emissions rules kicked in. Only Washington state even approaches that percentage, according to the trade publication, School Bus Fleets. 

Both state and Los Angeles-area regulators are formulating plans to clean up school buses. The most contentious issue is whether diesel fuel – which runs more than two-thirds of the school buses on California roads – can be reformed enough to keep it viable. 

The Air Resources Board held a hearing Monday in Sacramento – and will conduct another Thursday in El Monte – to ask citizens how it should spend $50 million in state money earmarked for cleaner school buses. The board is expected to allocate the money in December. 

Meanwhile, the South Coast Air Quality Management District, which includes Los Angeles, Orange and parts of Riverside and San Bernadino counties, is expected to soon propose rules that would force school districts to buy only the cleanest-burning buses. 

Diesel vehicles still have their backers. Oil companies, diesel engine manufacturers and many school districts want to allow the purchase of diesel vehicles, which they say are much cheaper and can burn 90 percent cleaner with low-sulfur fuel in the tank and pollution-cutting particulate traps attached to the exhaust. 

The alternative can be prohibitive: a particulate trap estimated to cost $7,500 versus a natural-gas bus about $25,000 more expensive than its diesel equivalent. 

“We’re all for cleaning up environment, and alternative fuel vehicles are great, but I do think diesel (should) be part of alternative fuels,” said Betty Manwill, director of transportation for the Irvine Unified School District. “We can clean up the air a lot faster.” 

Environmental groups support retrofitting diesel school buses to use particulate traps, but oppose allowing the purchase of new diesel vehicles.  

They contend that the new diesel technology – which is being tested on about 60 buses in the South Coast district – is failure-prone and still not as clean as natural gas. 

Government research shows that Californians have a one in 2,000 chance of getting cancer from diesel emissions. Within the South Coast district, the risk doubles. 

Controlling school-bus emissions is a particularly important task because studies have shown children to be more sensitive than adults to air pollution. 

The infrastructure for natural gas is more daunting than the vehicles themselves, said Alan Tomiyama, business manager for the Los Angeles Unified School District, which uses 1,300 district-owned or contracted buses, owns 33 natural-gas buses and is testing a half-dozen buses with particulate traps. 

The need for new fueling stations and ventilation systems can require fleet operators to spend millions replacing garages before their natural gas buses can start operating. 

Tomiyama said range is also an issue: His district’s natural-gas buses can run only about 100 miles between lengthy fuel-ups, so they can’t be used on some routes. 

Tomiyama said natural-gas buses are more expensive to operate, but officials at the Pupil Transportation Agency – the Whittier-based agency Bobadilla drives for – said their costs have been about the same. 

The agency – which has 13 natural-gas buses among its fleet of more than 100 – last month spent nearly a quarter less per gallon for natural-gas fuel than for diesel, said Stan Ross, director of transportation. 

There are some maintenance savings as well, said shop supervisor Bill Grimley.  

For instance, oil changes for diesel vehicles are needed six times more often than those for natural-gas engines, he said. 

Natural-gas engines are less powerful, but Grimley said he gladly accepts the trade-off. 

“I’d rather go up a hill slower with natural gas than with a diesel engine with all that black smoke,” he said. 

On the Net: 

www.arb.ca.gov 

www.nrdc.org