The hide is at the posted coordinates, but you must complete the challenge before you can claim the find.
The challenge is to fill your difficulty and terrain (DT) grid with traditional caches. Only 81 finds are strictly necessary, but I am guessing that all cachers who fulfill the challenge will have a fair few more than that. There is no time limit, caches can found before or after this challenge was published, and can be from anywhere in the world. You may sign the log book at any time in anticipation of meeting the challenge in the future.
My DT grid is attached as an image to show what a completed DT grid should look like and to demonstrate I have met the requirements of the challenge myself.
You can easily check if you meet requirements by looking at your statistics on Project-GC or using the challenge checker below.
This is a difficult challenge (hence the D5 rating), but for those cachers still to complete their traditional DT grid, it will be a rewarding experience to work towards this challenge. The terrain of this cache is around 2.5.