Mechanical cleanup was started shortly afterward using booms and skimmers, but the skimmers were not readily available during the first 24 hours following the spill, and thick oil and kelp tended to clog the equipment. Despite civilian insistence for a complete clean, only 10% of total oil was actually completely cleaned. Exxon was widely criticized for its slow response to cleaning up the disaster and John Devens, the mayor of Valdez, has said his community felt betrayed by Exxon's inadequate response to the crisis. More than 11,000 Alaska residents, along with some Exxon employees, worked throughout the region to try to restore the environment.