SACRAMENTO, Calif. (AP) – A new state-commissioned study says California’s 12 oldest prisons, some dating to the mid-1800s, need major repairs or replacements if they are to continue housing about a third of the state’s inmate population. The $5.4 million study by private consultants made public Tuesday says the majority of the prison buildings “are beyond their useful life.” They include San Quentin State Prison, built in 1852, and Folsom State Prison, built in 1880. The Kitchell CEM report comes as the state is already scrambling to fix deteriorating prison roofs that in some cases have required officials to stop using dining or housing areas. The consultants haven’t estimated the cost to fix all 12 prisons. But the projected cost for just one prison built in 1955 was estimated at more than $763 million.