WA Radio Scanner Users' Group

Gday guys, got some unencrypted chatter on the Central Park police p25 network this morning, im pretty sure it was WAPOL talking to control, both UID's came through clear as day, there was 22 hits over a few hours now nothing? anyone know what happing here? this is what i had in my scanner:

p25 trunk sys

freq:
502.143700
502.468700
502.781200
503.106200
503.306200
503.531200
503.731200
503.968700
505.662500
506.037500
506.675000

TGID 15

UID
2023015
2023815

all transmissions where picked up on 506.03750

figured out it is water police