She was back this morning, presumably laying more eggs into the hole...and digging up more of the yard. I was able to get a picture of her this time. Box turtle or snapper?
Here's a picture of the nest too (sorry, I have no idea how to arrange photos here). Yesterday you could see one of the eggs in there, covered mostly with mud. Today, it looks like she peed in the hole and maybe laid more eggs. (That's what I read, I know, it's kinda icky but hey, that's nature!)