Which is it: cleaner air or more buses?
The Metropolitan Transportation Authority, which boasts of having the world's largest fleet of clean-air vehicles, is considering putting the brakes on its policy of buying only alternative fuel vehicles in order to put more buses on the streets.
Diesel buses cost less than buses powered by natural gas. Put another way, the MTA can buy 290 diesel buses for the cost of 223 natural gas buses, but they pollute twice as much as alternative fuel vehicles even though they meet air pollution standards.
Environmentalists say that the purchase of diesel buses would signal a return to the smoke-belching vehicles cursed by anyone who ever found himself or herself behind one.
But since the alternative fuel policy was adopted in 1993, the MTA has come under a federal court order to improve the nation's most crowded bus system.
"The MTA board must balance the cost of incremental improvements in air quality versus the ability to put more service on the street faster," said MTA board member Mel Wilson, an appointee of Los Angeles Mayor Richard Riordan.
The MTA has been the nation's leader with more than 823 alternative fuel vehicles on the street or on order. In all, the MTA has 2,160 buses.
But the agency's 333 ethanol buses have turned into 40-foot lemons, breaking down so often that, on a typical day, one-third of the fleet is out of service, officials said.
As a result, the MTA has encountered high costs in maintaining the ethanol buses. They were originally powered by methanol, which also gave the agency problems.
Mechanical troubles have continued. Engines are being replaced every eight months and officials are talking about spending more money to convert the ethanol ones to natural gas or diesel.
An executive with the ethanol fuel supplier contended that the problems stem from improper maintenance, including use of the wrong engine oil.
The agency's large fleet of compressed natural gas buses are more reliable, officials said. But last year, an explosion of a compressed natural gas bus led the MTA to temporarily pull the entire fleet off the streets. Officials say the natural gas buses have undergone retrofitting and are safe.
The bus riders' group that helped win the federal consent decree mandating bus improvements said the MTA can increase service without compromising the public's health.
"Should poor people get a bus or be poisoned by a bus?" Chris Mathis, an activist with the Bus Riders Union, recently told an MTA panel. "These are not choices."
He suggested that the agency consider scaling back its rail construction program.
Environmentalists say that quality-of-life issues also must be considered when calculating costs.
"Try not to say 'clean diesel' in the same breath," said Linda Waade, executive director of the Coalition for Clean Air.
"This region spends $9 billion a year on the health effects related to air pollution," said Waade. "Everybody forgets that when they talk about [compressed natural gas] buses costing $50,000 more per bus."
When the MTA in 1993 voted to buy only alterative fuel vehicles to reduce the region's air pollution, it was considered a milestone on par with the elimination of backyard incinerators.
The reassessment of that policy comes at a critical time because the MTA is moving to replace its fleet-- one of the oldest in the nation. About 800 buses exceed the recommended federal replacement standard of 12 years.
The MTA board is expected to make a decision this fall when it considers bids for 233 new buses.
The Natural Resources Defense Council and the Coalition for Clean Air have said that any change in policy would be a "giant step backward" in efforts to clean up the air in America's smoggiest region.
MTA board member Wilson, however, said the current policy is preventing some neighborhoods from getting newer buses.
Currently, there are no natural gas fueling facilities at bus yards in South-Central Los Angeles, Cypress Park and West Hollywood. Building such facilities is expected to encounter neighborhood opposition.
As a result, residents dependent on public transportation are left to ride older buses.
Richard Hunt, MTA deputy executive officer for transit operations, said the agency may modify its policy to allow the purchase of some diesel vehicles even though they are not as clean-burning as alternative fuel buses.
The tricky task for the MTA will be to put more buses on the street while remembering that its mission also includes reducing pollution.
"The decision has to be made weighing both missions," said Los Angeles City Councilman Richard Alarcon.