Radiator fluid leak???

Well I'm befuddled! :confused: My 2000 Alero 3.4 with 200,000+ on her sprung a leak. I could have sworn it was the water pump laying down and just went ahead and changed it. NOT! After a closer examination, it looks like it is dripping off of the block between the crank pulley and the a/c pulley but closer to the a/c pulley. And it leaks pretty bad. Yesterday I pull up in the driveway and quite a bit leaked out. Just filled the reservoir back up after the pump change and it started dripping out almost immediately. Anybody ever experience anything like this in this area before? Can't imagine where it is coming from. Any ideas/experience sharing will be greatly appreciated gents. Thanks.

Additional info. I think I recall somebody once telling me that they had a similar leak and had chased it to an o-ring that apparently goes around the timing chain cover where the engine routes the radiator fluid as part of the cooling system. Sound familiar to anybody? If so, how difficult to do-it-yourself? Thanks again.