One thing I might suggest... Since (I assume) you will have a GMRS license holder at the central command office of the camp, why not set up a 5-watt, narrow band UHF base station on 462.6125 MHz, with no CTCSS tone. Put a small UHF antenna on your 40 foot pole, (use low-loss coax like LMR-400) and you will be able to cover your whole forest on the frequency known as FRS Channel 3. Tell everyone with FRS radios to stay off from channel 3 unless they have any emergency or need to get in touch with the camp headquarters, then just call on channel 3 with no privacy code. Even if those cheap bubble-pack radios can't talk to each other through the trees, they likely can be heard at the base station with the 40' high antenna, and with licensed 5 Watts at 40', they will hear you. Forget about a UHF repeater. NOTE: I'm just using channel 3 as an example, but any channel 7 or below could be used at 5 Watts. You could use higher power (50 Watts) on channels 15-22, but remember, a lot of older FRS-only radios don't go past 14, and channel 8-14 are low-power only. If there is any GMRS repeater within 50 miles, pick a channel 2 or 3 away from its output frequency, so its wide-band transmitter doesn't splatter on your narrow-band base receiver.