Here's a link which covers a dirt airstrip on the North edge of the Grand Canyon, L50 (Tuweep):
http://www.swaviator.com/html/issueMA02/Tuweep3402.html
The article mentions the ranger, Clair Roberts, but I've found out that Clair is no longer the resident ranger there, sad to say. My wife and I had our wedding ceremony at Toroweap overlook there in 1999, and Claire helped us out a great deal with the preparations. As far as I know, we're the only couple who ever had a wedding ceremony there.
We were camping there about a year before our wedding, in 1998, and we met a pilot who had flown into Tuweep and brought along a dirt bike in his plane; a pretty cool idea. If we hadn't met this fellow, I probably would never have known about the airstrip. Supposedly, its closed now, but it may still be possible to fly into there; I dunno.