This is a Challenge cache. So in additional to signing the log, you must satisfy the Challenge criteria as well.
The cache is hidden at the coordinates.
Normally date challenges are based on the day you find the cache. In this case it is based on the date the cache was hidden.
In order to attain the Gold standard you must have found a cache on 365 of the 366 possible days in the year.
This statistic is not readily available on www.geocaching.com but is available from project-gc.com. You can either take a screen shoot of your statistics or simply link your profile to project-gc. Instructions on how to do this are on the www.project-gc.com site. If you are are retired or otherwise have some time on your hands you could always list the 365 caches by date order in your find log. 
Rules:
1. All cache types in all locations qualify as long as they were active on www.geocaching.com when you found them. Caches found before the publication of this cache count.
2. You must have found caches placed on 365 of the 366 days of the year.
3. You have to find and sign the log book as well as qualifying for the challenge.
The challenge is based on dates, not on poking your hand into dark crevices. That said it is tucked away from casual walkers so I will tell you that the cache is hidden at the base of the big one.