I wouldn't call having all lifts open on December 27th on all snowmaking to be "compromised", but there is definitely a significant issue with the snowmaking on the summit, that I have found the source of.
That being said, the leak should be able to be fixed within this season. Really, the repair should take no more than 24 hours. The main pumphouse is near the reservoir, and pumps up one large diameter feed line to a valvehouse just above the North Quad unload. The line follows Pipeline and is above ground, but then disappears. It is most likely underground on Powder Pass, given that is where the water was visible, and it wasn't traceable to a particular source on the surface. The repair would consist of digging up the trail to locate the leak, then welding on a patch, pressure testing, and backfilling when it is confirmed that it is fixed. Now that there is snowmaking on the trail, they would be able to make snow on top of it and you wouldn't even know it was dug up in the first place. Killington has done multiple of these repairs all within 24 hours, though they don't have to do this anymore, as they replaced the pipe in all the problem spots.