The Town's own Environmental Impact Report says that. See the Town's assessment of extreme congestion of many intersections in the project vicinity here.
The only project-required change to existing substandard road conditions is a single right-turn lane extension at the westbound Diablo Road/Green Valley Road/McCauley Road intersection. That's like a tiny band-aid on a gaping wound.
Read concerns expressed to the Town by a local former Fire Battalion Chief, and by a 25-year veteran local firefighter