Although nobody has been able to provide me with an answer as of yet, I am lead to believe my issue lies within the heater core. More specifically, the heater core seals. We removed the interior floor from the drivers cabin, and were able to located signs of where the leak occured. When we started the car to attempt to get it to leak to pinpoint the problem however, the car showed no signs of antifreeze leaking. The explanation we are currently going with (which is apparently a known issue) is that volvo used 15 cent seals on their heater core, which is made of cheap plastic and is known to wear overtime. During colder temperatures, we believe the seal is loose and leakage occurs then (~freezing) During the summer weather however, the seal is warm and is keeping the antifreeze within the tubing (also whenever the car warms up, hence not TOO much antifreeze leaking really. We are replacing the seals with some $1.50 bosch seals, and hopefully that problem is solved. Any comments or other views into this problem is greatly appreciated still, as I am not going to attempt to replace the seals for another week or so.