I put it in my big tumbler and add amendments. It was full last fall and empty now.. I reuse it all the time.. Just add a lot of stuff. There are many recipes on how to do your own soil... look here. http://www.marijuanapassion.com/forum/forumdisplay.php?f=48
I heard on some growers that they don't recommend using the game soil but I still agree with everyone here. My Couz is using the same soil for his forth harverst and every yield has the same result. No problems.
I reused soil for years..but then I got hit with root knot menatoads(spelled that wrong)by the time I figured out what was wrong it was to late lost every thing,,i will never reuse soil again,,,many seem to have good luck reusing it so good luck to ya