In spring of 2011, State Senator Sam Blakeslee  and US Representative Lois Capps  both expressed concern for a renewed safety review. Speaking before the Senate Committee on Environment and Public Works, the congresswoman stated that she believed the "Nuclear Regulatory Commission should stay the license renewal process until the completion of independent, peer reviewed, advanced seismic studies of all faults in the area."
The Alliance for Nuclear Responsibility began circulating a petition to similar effect, going further and calling for an outright halt to relicensing. An array of San Luis Obispo-based anti-nuclear groups including Mothers for Peace also rallied and called for the closure of Diablo Canyon nuclear power plant.
The Alliance for Nuclear Responsibility also works at the level of the California Public Utilities Commission and initiated a letter writing campaign to Governor Jerry Brown, which requests he "instruct the CPUC to rescind the Certificate of Public Convenience and Necessity for ... Diablo Canyon ... and allow them to operate conditionally only under the agreement by the utilities to immediately begin to fully comply with completion of the state-directed AB 1632 [seismic]studies." 
The Alliance continued to maintain, through and including June 2011, a model letter for its supporters to send to the CPUC which states:
- RE: RELICENSING OF CALIFORNIA’S NUCLEAR PLANTS
- CPUC Application. 10-01-022 (Diablo Canyon)
- Dear Governor Brown and CPUC Commissioners:
- In light of the tragic events unfolding in Japan due to the earthquake, tsunami and nuclear meltdowns, we are gravely concerned about the seismic threats at California’s nuclear power plants. As the Japanese have ::sadly learned, despite assurances from their regulators, the seismic risks were greatly underestimated. After the discovery of a new fault only 1800 feet from Diablo Canyon, which has yet to be independently studied, ::analyzed, and peer reviewed, there is no reason to delay fully implementing the studies authorized under AB 1632 for both operating reactor sites.
- We ask that you instruct the CPUC to rescind the Certificate of Public Convenience and Necessity for both PG&E’s Diablo Canyon and SCE’s San Onofre nuclear power plants, and allow them to operate conditionally only ::under the agreement by the utilities to immediately begin to fully comply with completion of the state-directed AB 1632 studies. These studies must be completed and independently peer reviewed by 2015, and any ::ability of the utilities to operate the facilities after that date will be contingent upon the results of the studies and analysis.
- We cannot wait for a disaster like the one befalling Japan to strike before we act.
Both the San Luis Obispo and Santa Barbara Boards of Supervisors began discussing resolutions or letters supporting suspension of the processing of a re-licensing for Diablo. Rueters announced that the NRC agreed to suspend the environmental portion of the re-licensing application, but that the safety portions had already been completed.
According to Indymedia, a grass roots media project, protesters rallied on the weekend of April 16th demanding the closure of "Diablo Canyon Nuclear Power Plant". The article claimed that over 300 people gathered for the protest at Avila Beach in San Luis Obispo County. They also insisted that the Nuclear Regulatory Commission must halt PG&E's relicensing application process for the structure.The article continued to assert that the group Mothers for Peace was behind the fight to stop the construction of the nuclear power plant in the 1970s and was the organizer of Saturday's rally as well. Jane Swanson, speaking on behalf of the anti-nuclear organization, said that her group spearheaded the rally in response to the Fukushima nuclear disaster in Japan. She commented from the podium, "Mothers for Peace said in 1973 a workable evacuation plan is not possible at Diablo Canyon and in 2011 this is still true. It is time to shut it down". The crowd raised their voices in agreement, shouting "Shut it Down!" over and over.
Diablo Canyon was built and entered service despite legal challenges and civil disobedience from the anti-nuclear protesters of the Abalone Alliance. Over a two-week period in 1981, 1,900 activists were arrested at Diablo Canyon Power Plant. It was the largest arrest total in the history of the U.S. anti-nuclear movement.
- Hickey, Julia (April 17, 2001). "Anti-nuclear rally at Avila Beach". The Tribune. http://www.sanluisobispo.com/2011/04/16/1565807/anti-nuclear-rally-at-avila-beach.html.
- Wills, John (2006). Conservation Fallout: Nuclear Protest at Diablo Canyon. Reno: University of Nevada Press. ISBN 0874176808.