1999 Mercury Mountaineer EGR Exhaust Manifold Line Leaking

I have a problem with a cooling leak. It has been leaking coolant front somewhere under the hood for a couple of months, but the leak has been so small I could not find it. This morning however I noticed a small amount of smoke coming from under the hood and found a small hiss of steam coming from the EGR to Exhaust Manifold Tube at the Exhaust Manifold connection. My first thought is to try and tighten or replace the line, but is there a bigger problem brewing? I have had trouble over the last year with parts of the cooling system and have had many of the the lines, radiator, and heater core all replaced.

(5.0L V8)