Iv had that problem. Tilt the container at a steep angle so that the dirt won't fall but all the water will pool at the bottom. Then scoop out the water. Also you could squeze water out. And if neither of those things work then do the other thing I did and take a space heater and two heat lights to it.(I got the temperature to 160 degrees ferenheight.)
I had that problem recently. After burning some in the oven & microwave( yes the microwave can burn it) I found laying it out on several layers of newspaper it wil dryout in no time at all.
Then I discovered "T REX JUNGLE BED" sold at Petsmart is the same stuff and comes dried !!!