They have an 800mhz trunking radio set to "8-MTNCOM" or something like that abbreviation. The only traffic you might hear (if scanning via the County 800 trunking system) would be an ambulance with a minor "BLS" transport enroute to the facility just giving them a heads-up. Most call-ins for Paramedic "ALS" calls go through Arrowhead Regional or Loma Linda Univ. and occur either on cell-phone or 8-ALS-1 / 8-ALS-2. Then the MICN at ARMC or LLUMC will phone Mountains Comm. with the info about the incoming patient.
My friend got hurt snow boarding last weekend and I was with him at Mountain Community. I looked around and talked with a couple of people. They don't have a radio system except the county TRS. The antennas on the roof are for county fire's ECS group. When they are activated they staff MCH and the fire stations for the areas served.