Okay, so this happened to me twice. What happened was: I was using a quarry powered by redstone energy cells via a conduit from Thermal Expansion to mine a large chunk. Both times, after an IRL day (it wasn't on all the time, I loaded the world multiple times) the chunk the quarry was in reset, with a different seed! I used an enderchest on top of the quarry that my Applied Energistics system was getting items from, and both times I noticed that the quarry had stopped putting blocks in the enderchest. The second time this was especially odd, because I had hooked up a steam engine powered by steam in an endertank in a different chunk. When I checked it out, the chunk had regenerated. Not even with the same seed, the terrain was different and it had changed from a taiga biome to a woodlands biome, or something like that. I'm not sure what mod has this bug, because I was using at least 3 mods in each setup where the chunk was reset, so I just want to know: Has this ever happened to you? You had a quarry in a chunk and the chunk it was in was regenerated with a different seed?