Inmates from a medium-security state prison in Norco could help staff a city fire station that has been closed since 1982, under a plan being discussed by Corrections Department and city officials. An engine company now based inside the California Rehabilitation Center would move just outside the prison fences to the city's old Corydon station, providing quicker response times and valuable aid to city firefighters, said City Manager John Donlevy. The ranks of city firefighters were trimmed severely in the same wave of city budget cuts that closed the fire station. Firefighters oppose the plan. A decision to reopen the fire station with state personnel and prisoners is not imminent, Bob Borg, superintendent of the California Rehabilitation Center, said.