One of the more elusive federal agencies to monitor is the Environmental Protection Agency, or EPA. They have a visible presence at many events, including many of the Homeland Security operational training simulations, but not many people have actually logged any EPA radio traffic.
I was once at a raid involving the local police and agents from the EPA, but it appeared that the EPA folks were carrying UHF radios on the police system.
In my preparation to visit the EPA's research vessel BOLD, I pulled up all the EPA frequency allocations I could muster:
40.9700
41.6300
49.8600
163.4375 - Nationwide allocation (shared)
164.1000
164.4500 - Nationwide allocation (shared)
165.2375 - DHS CBP Customs (EPA contracted dispatch)
165.4125 - Nationwide allocation (shared)
166.1250
166.4375 - DHS CBP Customs (EPA contracted dispatch)
167.0750
167.1500
168.5000
168.5250
168.6500
168.8500
169.0000
169.1750
169.5750
169.9750
170.1250
170.3750
170.4000
172.5500 - Nationwide allocation (shared)
172.7000 - Nationwide allocation (shared)
173.0250
173.9125
406.1500
406.2250
408.0000
409.2000
416.1000
419.6500
Besides these frequencies, be sure and try the nationwide federal interoperability channels and federal itinerant channels. And I'm sure the VHF marine band channels would be in use on any operations on or near the water. I have no area specific allocations, so try all these and let me know if you hear anything.
