This tool lets you pick a piece of geometry and fill it with closely packed grains that clump together like wet sand. It essentially creates the same network as 
Dry Sand but enables clumping weights and sets an attribute called wetness. This attribute is useful for creating partially wet and partially dry sand, such as a sandbox or a beach.
Using Wet Sand
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Select the geometry object to convert to wet sand.
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Click the
Wet Sand tool on the Grains tab.
For specific parameter information, see the POP Grains help.
Note
Scaling is an issue for sand because the number of grains are based on how many particles are around it. Changing resolutions may change results.
