This is a challenge cache located at the published coordinates. In order to log it, you must have at least 31 virtual cache finds such that one is found on the first day of a month, another on the second day of some month, etc. up to one found on the 31st day of a month. The finds do not have to be on consecutive days or even in the same year.
The cache is at the given coordinates. I have verified that I qualify.
If you sign the log before the challenge is met, just write a note on the cache page. When you meet the challenge, claim a "Found it" and verify using this checker:
