hi sigmund,
I wasnt quite clear from your description where you found wet ground. More details would be helpful. Pictures if you have them.
Step one - determine "where" on the pipe the leak is coming from. Is the whole thing bad or just one spot?
BTW, I can tell you how to turn a "honey, we just need to fix the leaky standpipe" into a $30K complete rennovation!
Gator