Santa Clara County has adopted G100UL fuel, the first jurisdiction in the US to do so, despite concerns about its lack of ASTM approval and potential compatibility issues with other unleaded fuels like Swift 100R. The decision to adopt G100UL, driven by political pressure and a desire to reduce lead emissions, raises questions about liability, infrastructure, and potential financial risks to the community. The Board of Supervisors is urged to address these concerns and provide guidance to the airport community.