tensioner causing coolant leak

I just bought a 1999 Trans Am w/ an LS1 and 6 speed. The title may be a bit misleading, the tensioner doesn't cause the leak but when I take the tension off of the belt a coolant leak starts behind the bell/pulley on the water pump. It makes a small pool on the ground then stops.

I found this leak when changing the A/C belt behind the main drive belt. The temp. gauge on the car stays at a steady 210 degrees, so theres no over heating issues. Though I had to add a little bit of coolant when I first bought it, it was nothing to make me worry. Until I found the leak. If you release the tension, the leak starts, but stops immediately when you let off the tensioner, putting tension back on the belt. Am I going to need a new water pump soon?? I've done some searching on the web and haven't come across anything. Thanks.
Sean  

Sean,

The title was misleading, I went "WHAT?!?" when I saw this post!

Well, with no tension, is it possible that some of the bolts are a little loose, causing the leak? Maybe check those first and tighten them up (if need be). It is also possible that the gasket is crushed/leaking/torn and that should be replaced.

How many miles are on the car?  

Hi, thank you for the reply. I've checked the bolts and they are all tight. Theres 138 thousand on the car. It seems to be coming from behind the pulley/bell where you cant see. Also I went out there today and released the tension and wiggled the bell a little, there seemed to be a very slight amount of play. Not enough for me to notice at first, but enough for a leak around the shaft if there's normally no play there. (I would imagine) I'm still not sure though, also when I did that today, there was no leak, though I didn't stay trying.