The move follows a long pressure campaign by environmental and NYC community organizations, who enlisted the help of Governor Pataki and State Senate Transportation Committee Chair Norman Levy during the past few years.

Still at issue is exactly what type of bus NYC Transit will buy -- NRDC is pushing for the compressed natural gas (CNG) buses already in use by Long Island Bus and other transit agencies. NYC Transit President Lawrence Reuter was cited in press reports Thursday favoring hybrid electric-diesel buses that generate electricity on-board with an efficient, steady-burning diesel engine. The electricity powers drive motors at each wheel, permitting a rider-friendly low floor design. At the unveiling of the hybrid's prototype in February, MTA officials hailed it as the "bus of the future" and said it would be ready to hit the streets in large numbers by 1999, though others were skeptical of this timetable for an unproven technology. Reuter said the hybrids would avoid the need for costly fueling depot conversion to CNG, though NRDC and NYC Transit cite different figures regarding conversion costs ($29 million vs $70 million).

The U.S. Environmental Protection Agency will likely tighten federal standards for particulate pollution (which comes from diesel engines and other sources) during the next year. This will lend further impetus to cleaning up urban bus fleets. NRDC estimates particulates cause 4,000 premature deaths in NYC each year.v