The cache is NOT at the posted coordinates, but you do need to go there. This is a field puzzle.
Signal's canine pal Tracker buried his collection of bones nearby. Can you find them? He encoded a passphrase using the park rules sign.
6‑3‑1 / 2‑4‑2 / 1‑1‑2 / 1‑2‑3
3‑18‑1 / 2‑2‑2 / 5‑2‑1 / 2‑3‑1 / 9-3-2 / 2‑7‑2
14-2-1 / 13-8-1 / 2‑1‑2 / 3‑1‑3 / 3‑9‑1 / 9‑16‑1
15‑2‑4 / 13‑2‑2 / 14‑7‑2 / 12-2-5
2‑7‑2 / 2‑2‑2 / 3‑2‑4 / 2‑4‑2
The park is open daily from 7:00 AM to dusk.