Castle Airport Castle Airport is a public use airport located seven nautical miles ( 13 km ) northwest of the central business district of Merced , a city in Merced County , California , United States . It is operated by the Merced County Department of Commerce , Aviation , and Economic Development . The airport is located at the former Castle Air Force Base which closed in 1995 . This land is owned jointly by the city of Merced , city of Atwater and the county of Merced . Until 2007 this land was administered by the JPA or Joint Powers Administration . It serves one school , Sierra Academy of Aeronautics , which specializes in training foreign pilots , from the People ' s Republic of China . Activity related to this school makes up the majority of the air traffic at Castle . In early 2007 , the control tower was reopened to handle increased training traffic . Castle Air Museum is away , displaying over 50 restored World War II , Korean War , and Cold War era aircraft . Among the exhibit highlights are a Lockheed SR - 71 Blackbird , the world ' s fastest manned aircraft , and the massive Convair RB - 36 Peacemaker , the only surviving reconnaissance variant of the largest bomber ever built for the United States Air Force . Facilities and aircraft . Castle Airport covers an area of which contains one runway ( 13 / 31 ) with an 11 , 802 x 150 ft ( 3 , 597 x 46 m ) asphalt and concrete pavement . For the 12 - month period ending July 1 , 2010 , the airport had 72 , 153 aircraft operations , an average of 198 per day : 98 % general aviation and less than 2 % military , air taxi , and scheduled commercial . At that time there were 80 aircraft based at this airport : 85 % single - engine , 12 % multi - engine and 3 % jet . Pollution . Since the mid - 1940s , aircraft maintenance , fuel management , and fire training activities on the base have generated wastes that consist primarily of waste fuels , oils , solvents , and cleaners . Base activities also have generated lesser amounts of paints and plating wastes . The EPA currently has this base listed on their database due to the bulk wastes such as solvents , oils , fuels , and sludges which were disposed in pits at landfills around the base until 1977 . Fuel and waste oils were incinerated by the Air Force during fire training exercises . The Air Force ceased disposal of hazardous waste on site in 1977 , and the base was officially closed in 1995 . During the following cleanup efforts , all hazardous and toxic materials that the Air Force was unwilling or unable to transport offsite were sealed into four onsite landfills . EPA investigations have been completed at multiple areas of contamination including landfills , discharge areas , chemical disposal areas , fire training areas , fuel spill areas , and polychlorinated biphenyl ( PCB ) spill areas . Through the fiscal year 2006 , $ 164 . 27 million was spent on cleanup activities at Castle . The USAF expects to spend an additional $ 70 . 98 million through fiscal year 2044 . Approximately 6000 people obtain their drinking water from both municipal and private wells located near the site . The principal pollutant at the base , trichloroethylene ( TCE ) , was found in a plume . Merced Irrigation purified the water at the edge of the plume and released the purified water outside the plume . Working their way inward , they managed to clean the contaminated water . The methods used to purify the groundwater included passing the water through carbon filters and then aerating it . The pollutant remaining after purification was packaged in a barrel and removed from the site . In 1991 , a Base Realignment and Closure ( BRAC ) Cleanup Team ( BCT ) was created to review and offer comments / recommendations on the progress of the cleanup effort at Castle . BCT membership included representatives from the Air Force , federal and state regulatory agencies , and appointed representatives from the governing bodies of surrounding communities . The Castle RAB , or Restoration Advisory Board , which was established in 1994 on behalf of the former Castle Air Force Base , was responsible for reviewing Federal cleanup methods and efforts , and was officially adjourned on January 16 , 2007 . Air National Guard . In 2004 , recommendations were made to relocate the 129th Rescue Wing ( 129 RQW ) of the California Air National Guard and its associated HC - 130 , MC - 130 and HH - 60 aircraft from Moffett Federal Airfield ( formerly Naval Air Station Moffett Field ) to the former Castle Air Force Base , now Castle Airport . Rationale for this move was the high cost of living in the Sunnyvale / Mountain View / San Francisco Bay Area for full - time Active Guard and Reserve ( AGR ) and Air Reserve Technician ( ART ) personnel assigned to the unit , and the travel time and non - reimbursed expenses cost for " traditional " part - time air national guardsmen serving in the unit , most of whom reside in the San Joaquin Valley region due to lower cost of living . It was estimated that the cost to relocate the 129 RQW to Castle , to include associated military construction ( MILCON ) costs , could be recouped in seven ( 7 ) years . This would result in the reestablishment of an Air Force cantonment area at Castle that would be renamed either Castle Air National Guard Base or Castle Air National Guard Station . However , likely due to organizational restructuring currently occurring in the Air National Guard nation - wide and higher priority defense spending requirements for the U . S . Air Force , the National Guard Bureau and the Air National Guard since September 2001 , this initiative has been placed on indefinite hold and the 129 RQW remains at Moffett . California High - Speed Rail . With its central location in the San Joaquin Valley , on the route of the proposed California High - Speed Rail system , and with a large , underdeveloped site , Castle Airport has been submitted as a possible location for the central maintenance facility for the system .