Pilot Scientist Stephen Conley over Aliso (IMAGE) University of California - Davis Caption UC Davis scientist and pilot Stephen Conley flies over Aliso Canyon to take measurements of methane spewing from the natural gas storage facility in Southern California in January 2016. Scientists confirm the methane leak is the largest in US history. Credit Joe Proudman/UC Davis Usage Restrictions Provide credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.