"Under the agreement we have to compact and destroy the two buses we are replacing," Buxbaum said, adding the district will destroy the old buses once it receives the new buses.
He said the CNG buses will be fueled in El Centro at the new fueling station opened for natural gas buses.
The El Centro Elementary School District recently purchased a low-emission, clean-powered bus.
For the value of the price CUSD is getting for the buses, Buxbaum said district officials don't mind driving to El Centro to fuel the buses.
He added if CUSD decides to go with all CNG buses in the future, a fueling station in Calexico might be built.
The agreement with the Energy Commission will allocate money from the program to school districts, which in turn will buy buses fueled by either low-sulfur diesel or natural gas.
"Our cost is about $35,000 per bus," said Buxbaum, adding the district will probably have to pay to upgrade the air conditioning in the buses.
He said the buses will be used "for all the schools (in the district) in some capacity."
A total of 66 clean-powered buses — 37 powered by compressed natural gas, three by liquefied petroleum gas and 26 by clean diesel — will be procured by districts from Shasta County to Imperial County.
"The great thing about these school buses is that they are safer for children and cleaner for the environment," said Energy Commission Chairman William Keese.
In the 2000-2001 state budget, Gov. Gray Davis provided $50 million to the low-emission program to continue the replacement or retrofit of school buses to improve the health and safety of school children.
The California Air Resources Board is running the $12.5 million retrofit program.
The California Energy Commission will spend $7.5 million for the 66 clean-powered buses and some fueling stations for various school districts throughout the state.
The idea behind the program is to phase out or retrofit all aging buses throughout the state.
More than 44 percent of school buses in California are older than 13 years, while 12 percent of the vehicles are more than 23 years old.