Using the TopoZone mapping program I have on my laptop, I was able to figure out how to drive to the general location without much trouble. The figuring was not much trouble, that is. The actual drive was slightly less trouble free. Since I was driving from Pullman via Palouse, it looked like I would be best off going on Kriebel Road, just south of Ladow Butte. This turned out to be an ill-advised short cut since Kriebel Road is apparently not so well travelled this time of year and there was still snow in drifts across significant portions of the road. After driving as far as I could (and probably quite a bit farther than I should have), was able to back up for a ways, but unfortunately not far enough. I got stuck a few different times and tried digging the snow out and putting tree branches under the tires to improve traction. Both of these things helped a little bit, but they would only get me a few feet. Finally I had the bright idea to put the chains on. That's not so easy when the wheels are already sunk a few inches into the snow. With a little bit of effort, I prevailed and did not have too much trouble after that. It was a little bit of work getting back up the hill, but I was able to make it. I discovered when I went to take the chains off that one of them had already fallen off (which was probably the reason I was not able to drive right up the hill). It was probably a good thing I had not put the chains on in the first place because I probably would have kept driving and then gotten really stuck in a place where the chains did not help.
After getting back to the more well travelled Ladow Road, I able to stay on roads which were entirely snow free. I parked along Schneider Road at the point which was pretty much the closest I could find (according to the GPS) on the road. The hike was a little less than .75 miles and mainly involved walking through patches of trees and across partially snow covered fields. Without too much difficulty I followed the directions given by the GPS and made it to (roughly) 47°N 117°W where I took a few pictures to submit to the DCP. The ensuing walk back to the pickup and drive back to Pullman went without a hitch.