To complete "Destroy Sand Castles in a 124+ zone"; you need to have the Locating quest "Collect 60 BluGlo in a 124+ zone" active at the same time.
To complete "Destroy Fish Shaped Rocks in a 140 zone"; you need to have the Locating quest "Build a Radar Tower in a 140 zone" active at the same time.
This is purely because Destroy 11 and 12, both point to Locating 11 and 12 in the files.
Extremely literal explanation in screenshot below.
The "Destroy" questline has a Survivor Charger in it, so you probably don't wanna miss out on it.
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