95 Blazer loosing coolant

[71-C10]

I have a 95 Blazer that has a coolant leak somewhere. Last week, it started running a little hotter than usual. I checked the radiator, and it was low. I put coolant in it, and it stopped getting hot. Problem here is it ran at less than 200 degrees and the heater did not get the interior warm. I took it to my mechanic and he replaced the thermostat along with a flush, fresh coolant, and a radiator cap. I still had a smell of antifreeze, but I could not find a leak. I drove it again yesterday, and it still had an antifreeze smell. I looked in the radiator and it was low again by a quart. The recovery tank was full. My wife drove it to work and later in the morning she looked out at it and noticed a small puddle under it. She went out and moved it back, and the puddle was indeed antifreeze. Also she noticed it dripping between the radiator and the front of the engine. Where she works is not far from the shop, so she took it back. Before she left, she opened the radiator (now cold) and it was full. My mechanic thought at first it may be a water pump. Now he doesn't think so. Right now, he's trying to find the source of the leak. He say's it might be the intake gasket. Anybody had a problem like this with a 4.3? Oil is not contaminated. and is at the full mark. Blazer does not smoke at all. Antifreeze is green.