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 the case it is based on the date the cache was hidden.
In order to attain the Silver standard you must have found a cache on 244 of the 366 possible days in the year.
This statistic is not 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 have a job with internet access and no supervison you could always list the 244 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 244 of the 366 days of the year.
3. You have to find and sign the log book as well as qualifying for the challenge.
A spoiler photo is included in the gallery since the challenge is based on dates, not on poking your hand into random dark crevices. Its pretty poor but it was taken in low light with a phone.