Following a report published in the Sacramento Bee in November of last year, which uncovered evidence indicating that the technician in charge of testing the structural integrity of the San Francisco-Oakland Bay Bridge had been caught falsifying test data on previous projects, the California Department of Transportation (Caltrans) launched a special investigation into the reliability of the safety test results for many of its construction projects. The team of engineers assigned to this project has discovered doctored test results and other discrepancies warranting further investigation into the actual safety of several Caltrans construction projects, including the San Francisco-Oakland Bay Bridge’s eastern span, which connects the bridge to Yerba Buena Island.
According to reports and emails obtained by the Sacramento Bee from the Federal Highway Administration, more than 20 of the radiation tests used to verify the structural integrity of the reinforced concrete foundations of California bridges including the Bay Bridge, the Dunbarton Bridge, and others, contain suspicious irregularities that merit further investigation.
In December of 2011, a team of Caltrans engineers began to review the results of recent gamma gamma logging tests. These tests use radiation to scan the surfaces of bridge and roadway support piles for defects that may compromise the foundation, and the Caltrans engineers reportedly found many inconsistencies in the gamma gamma logging results indicating possible falsifications, some dating back to 2004. Some of these data irregularities include possible copying and pasting from other test results, inaccurate data file time stamps, and erroneous test meter calibration information. The engineering team is currently unable to accurately report the number of serious falsifications or the extent of their effect on the reliability of the information Caltrans currently possesses regarding the structural integrity of the these bridges. The expected due date for the engineering team’s final report, originally intended for a summer release, has been pushed back to fall. Before the results are made public, the team’s research methods and results will be scrutinized by an independent panel working on behalf of the Federal Highway Administration.
The administration has previously criticized Caltrans’ oversight of safety testing procedures – particularly their continued reliance on radiation test results conducted by a technician who admitted to fabricating previous test results and Caltrans’ failure to notify federal officials after the falsification of these test results became known to the state agency.
The chair of California’s Senate Transportation Committee has scheduled a public hearing to discuss these issues on August 14.