Four alternative fuel buses are taking kids to and from Tucson-area schools, which officials hope will reduce air pollution and even kidsβ asthma.
Tucson Clean Cities, a Pima Association of Governments program, received a $150,000 grant to replace six buses with cleaner fuel alternatives in Amphitheater Public Schools and the Marana Unified School District, as well as the Chandler Unified School District in the Phoenix area.
The grant, a part of the Diesel Emissions Reduction Act, came from the U.S. Environmental Protection Agencyβs West Coast Collaborative partnership.
Each district retrofitted two buses. Maranaβs run on compressed natural gas and Amphiβs run on propane, John Mikulin of the EPAβs West Coast region said via email. The newer vehicles must comply with βmuch more stringent exhaust emissions standards,β so they generate less air pollution, he said.
The federal limits are based on how much ozone a personβs body can tolerate over eight hours, said Beth Gorman, a senior program manager for the Pima County Department of Environmental Quality.
Pima County is at 69 parts per billion, nearly exceeding the new EPA standard of 70 parts per billion, Gorman said. However, that is an average of the highest level over the course of three years, she said, and does not represent Pima County air quality all the time.
The EPA tightened air quality standards in fall 2015, and will determine in 2017 whether Arizona counties comply.
Reducing bus pollution is an important factor in the health of schoolchildren, according to the 2014 State of the Air report from the American Lung Association.
About 11 percent of kids in Pima County have asthma, making them a vulnerable population when it comes to air pollution.
Mikulin said the new buses will not only produce quantifiable results of environmental benefits, but also increase awareness among parents and school officials about the need for improved air quality.
Marc Lappitt, director of transportation and food service for Amphi Schools, said he is a strong believer in alternative fuels and their benefits for school buses.
Propane was chosen for the school district over other cleaner alternative fuels due to its smaller storage requirements and fewer regulations than compressed natural gas, he said.
The buses are quieter and the fleet is cheaper to maintain than diesel, he said.
βThe bus drivers enjoy driving them as much or more so than they did a conventional diesel bus,β he said.
Amphi recently used school bond money to buy seven more alternative fuel buses for delivery next school year, Lappitt said.
Of the districtβs approximately 120 buses, 22 are propane, he said. Of the remaining diesel buses in the fleet, all are bio-diesel.
The grant program includes a policy for drivers to reduce idling at schools, said Colleen Crowninshield, the PAG Clean Cities manager, via email.
βVehicle exhaust is the leading source of hazardous air pollution in Arizona,β she said.
One example of how Amphi reduces idling, Lappitt said, is having multiple bus drivers sit on one bus to get their air conditioning while waiting after school, instead of having multiple buses idle in order for each driver to get cool air.
βItβs just a constant vigilant effort by our district to minimize school bus idling,β he said.
β βNo Idling β Young Lungs at Workβ signs are posted where children are dropped off to remind parents and bus drivers that turning off their engines curbs tailpipe emissions,β said Crowninshield. βBy simply turning off their engines, drivers can make a difference in reducing emissions.β
Gorman, of Pima County, notes that in a schoolyard parents idle their cars waiting in line for their kids after school. Childrenβs lungs are not fully developed until their late teens, Gorman said, so being outside and breathing polluted air during recess or outside activities can be harmful.
βWhatever we can do to help reduce our vehicle emissions is really going to help,β Gorman said.
