This is only a multicache because there is something to find
at the listed coords. However, unless you've solved the puzzle and
taken along (or arranged access to) a piece of required
information, you're not going to find it!
This is a fake log 
but the answer to this puzzle has more to do with the natural
variety.
These ravers are probably using e 
and so should you! Just not the type that comes as a pill and
makes you feel good (oh, and suppresses your immune system and
other nasty side-effects...); the other e!
At the listed coordinates, you'll find a post by a gate, near a
parking spot at a sharp corner. On this post, you'll find a six
digit number which tells you how many past the point you need to go
to get another six digit number, ABCDEF. Use these numbers in the
format
S 31° 56.ABC E116° 02.DEF
to find the cache, which is a grey clip-lock container in some
rocks.
Free clue! A=6!