From the Executive Summary: "The U.S. Department of Homeland Security/Federal Management Agency (DHS/FEMA), Region IX National Preparedness Division - Technological Hazards Branch, evaluated an offsite biennial Plume Phase Exercise in the Plume Exposure Pathway Emergency Planning Zone (EPZ) around the Diablo Canyon Power Plant (DCPP) on November 7, 2012. Out-of-sequence interviews were conducted on November 8, 2012. [...] This After Action Report (AAR) contains the draft written evaluation of the biennial exercise. All state and local organizations, except where noted in this report, demonstrated knowledge of their emergency response plans and procedures and adequately implemented them. There were no deficiencies and no Area Requiring Corrective Action (ARCA) identified during the course of the exercise. No ARCAs were corrected and there were no ARCAs from a previous exercise corrected."
U.S. Nuclear Regulatory Commission: https://www.nrc.gov/
Diablo Canyon Power Plant. San Luis Obispo County, CA. November 7, 2012