The Granite Chief Wilderness was expanded in the northwest by a purchase of both logged and unlogged watershed lands by the American River Conservancy. Some of these lands were added to the wilderness, some are undergoing restoration. The wilderness is now about 115 km2 ( about 28,374 acres), an addition of 11 km2 (about 2800 acres) to the original 104 km2 (25,680 acres). These areal measurements are approximate.
The map below shows this new boundary, which can be accessed at https://www.gaiagps.com/datasummary/area/860a1d85-93c5-4fc9-b2e3-dfd6c82f1a53/. The outline came from an official USDA Forest Service geodatabase. This area and map is part of my long term project of getting all the trails mapped via tracing or tracks, and providing that info to you.