Complex sentence: The property was once the site of a large settlement of Chumash people, a Native American community, so when the university tried to expand to accommodate an undergraduate program it met resistance from environmentalists seeking to protect the Chumash ancestral site and the wilderness terrain.
Split into simpler sentences: The property was once the site of a large settlement of Chumash people, a Native American community. When the university tried to expand to accommodate an undergraduate program it met resistance from environmentalists seeking to protect the Chumash ancestral site and the wilderness terrain.