All Cities Utilize Countywide Coordinated Communications System (CCCS) Trunked Radio System.
Non Trunked Talk-Around (TA) Frequencies (sometimes encrypted) are Supplementary and used on Local basis as needed.
Non Trunked Frequencies Supplementary to Countywide Coordinated Communications System (CCCS)
See - Office of Emergency Services (Cal OES)
Fire/EMS - Los Angeles County Fire
Police - Brea Police
OCTA manages the FSP program and CHP provides dispatch and field services whenever law enforcement is required. The frequencies are licensed to OCTA.