Aside from looking at the antennas on the trucks to determine the band, my guess is they are on VHF-lo. The low-band Burlington county and NJ state radios around here have been silent for years.
I've had both in my scanner for a while and have never heard a peep on either one. I've never sat on them either though. If I had to guess, it would be VHF, since the rest of the township operates on VHF.
They actually use the vhf one with that pl but they dont really talk that much on it. The old 45mhz channel still exists but only for green twnshp dpw. I confirmed today. Also use to work there.