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Diablo Canyon stopped for ever, California, United States


On June 21, 2016, PG&E announced a proposal written with labor and environmental organizations to increase investment in energy efficiency, renewables and storage, while phasing out nuclear power. Specifically, the operating licenses for Diablo Canyon Units 1 and 2 will not be renewed. These were set to expire on November 2, 2024 and August 26, 2025 respectively. Diablo Canyon has been famous in the annals of environmental struggles since the 1960s (4), when in 1966 the Sierra Club Board voted to endorse the Diablo Canyon site. They discovered later that it was  home to the largest Abalone site in California. A major campaign to reverse the astonishing endorsement of the atomic plant by the Sierrra Club was started by several board members inclusiding David Brower. All this led to the founding of Friends of the Earth. There was civil disobedience and many protests against Diablo Canyon. In 1977,  "activists staged civil disobedience at the gates of Diablo Canyon.

47 were arrested while 1,500 others showed support at a nearby rally. Activists did statewide teach-ins to educate the public about Diablo Canyon and nukes" (4). In September 1981,"the Abalone Alliance starts a blockade of Diablo Canyon that lasts two weeks. Over 1,900 people are arrested, while tens of thousands show up to support them" (4).  In any case Diablo Canyon was built (although it was alleged that the site suffered the risk of an earthquake) and it  functioned until 2016, when the decisions was taken to close it down.  Political and environmental presures lies behind this decisions. In October 2010 a major controversy had arisen when California enacted a new policy banning the use of antiquated "once-through cooling" systems, which allow coastal power plants to directly take in and discharge massive amounts of sea water -- causing significant damage to marine creatures and the environment. While all plants were supposed to comply with the policy by 2015, Diablo Canyon was given the opportunity to instead explain by 2015 why they should not comply with the policy or face compliance by 2024. As Diablo Canyon caused some 80 percent of the damage to the marine environment of all the coastal power plants combined, excluding Diablo from the policy would make a mockery of the program. (5). ========================================= == In June 2016, pro-nuclear analysts still lament that Diablo Canyon Nuclear Power Plant in San Luis Obispo County, California is closing down. They say that "the plant is safe, can withstand an large earthquake, tsunami and any other disaster, provides billions to the local economy, and produces more clean energy than all the wind turbines in California combined".(2)  For critics who have long insisted that nuclear power is inherently dangerous and too expensive, the prospect of delivering a death blow to Diablo was something to relish. "Two nuclear plants are down in California and we're working on a third  one which is Diablo Canyon," said Kathryn Phillips, director of Sierra Club California, referring to the San Onofre Nuclear Generating Station in early 2012 and the Rancho Seco plant near Sacramento in 1989.  (1).  PG&E claims that  nuclear energy will be replaced completely with gains in efficiency and renewables. "But the proposal’s details do not back this up. In fact, it calls for implementing renewables and efficiency equal to only about a quarter of Diablo Canyon’s generation. Instead, experts agree, the generation will mainly be replaced by natural gas, and attempts to buy energy from out-of-state." (2). Whether it is solar and wid, or increased efficiency, or natural gas that replaces Diablo Canyon, the fact is that its closing down signals the end of nuclear commercial energy in California. The decommisioning expenditures will be very high , and as usual there is no clear plan for coping with the nuclear waste. On the whole, however, the closure plan is a final blow for commercial  nuclear energy in California. The impending closure of Diablo Canyon would leave just one nuclear plant on the West Coast, the Columbia Generating Station, about 200 miles outside of Seattle.  To craft the closing down proposal, PG&E worked with the International Brotherhood of Electrical Workers Local 1245, the Coalition of California Utility Employees, the Natural Resources Defense Council, Environment California, Friends of the Earth and the Alliance for Nuclear Responsibility.

Basic Data

Name of conflict:Diablo Canyon stopped for ever, California, United States
Country:United States of America
State or province:California
Location of conflict:San Luis Obispo
Accuracy of locationHIGH (Local level)

Source of Conflict

Type of conflict. 1st level:Nuclear
Type of conflict. 2nd level:Nuclear power plants
Specific commodities:Electricity

Project Details and Actors

Project details

The Diablo Canyon nuclear facility near San Luis Obispo was the only nuclear energy plant left in California by 2016. It was approved in the late 1960s when public sentiment in California was starting to shift from embracing nuclear power to opposing it (1). PG&E made in 1977 its 5th revision to costs. Unit 1 costs were $695,000,000 with an operational date of 3/15/78. Unit 2 costs were $560,000,000 with an operational date of 10/15/78 (4). Diablo Canyon's two units had a capacity of 1,073 and 1,087 MWe, generatings almost 18,000 gigawatt-hours of power each year, powering 1.7 million homes. By itself, Diablo Canyon, operated by Pacific Gas & Electric, accounted for nearly 9 percent of California's electricity production. PG&E could have applied for a 20-year extension through the Nuclear Regulatory Commission.

As required by California law, PG&E has established a trust fund created by ratepayers, through their electricity bills over the course of decades, to cover decommissioning costs. The trust fund for Diablo Canyon is nearly $2.8 billion. In PG&E's most recent submission to the California Public Utilities Commission, the utility estimated it would cost $3.779 billion to decommission Diablo Canyon. (3). The nuclear waste will be kept on site because, as in the case with all nuclear facilities in the US, companies are not liable for final disposal: it is the federal government's responsibility to ultimately find places to deposit nuclear waste. However, with the proposed depository at Yucca Mountain in Nevada scrapped, nuclear facilities keep spent fuel at their respective sites.

For nuclear's supporters, Diablo Canyon was seen as essential to deliver reliable, base-load power and an effective way to reach the state's ambitious goals to reduce greenhouse gas emissions. "Diablo Canyon is an absolutely necessary part of the energy mix in California," had said Eugene Grecheck, president of the American Nuclear Society. This was not to be, however. It's not just California. There are 99 nuclear reactors in the U.S. providing in 2016, 19 percent of the nation's electricity. But the majority of those 99 plants are over 30 years old.

Project area:300
Level of Investment:3,800,000,000 (only the cost of decomissioning)
Type of populationSemi-urban
Affected Population:50,000
Start of the conflict:1966
End of the conflict:2016
Company names or state enterprises:Pacific Gas and Electric (PG&E) from United States of America
Relevant government actors:Government of California
Nuclear Regulatory Commission
Environmental justice organizations (and other supporters) and their websites, if available:Abalone Alliance
Sierra Club (after initially supporting the nuclear power plant)
Scenic Shoreline Preservation Conference (SSPC)
Friends of the Earth
The Mothers For Peace
The Natural Resources Defense Council
Environment California
Alliance for Nuclear Responsibility.

Conflict & Mobilization

IntensityHIGH (widespread, mass mobilization, violence, arrests, etc...)
Reaction stagePREVENTIVE resistance (precautionary phase)
Groups mobilizing:International ejos
Local ejos
Local government/political parties
Social movements
Trade unions
Recreational users
Local scientists/professionals
Important role in the blockade of 1981 of Mothers for Peace and the Abalone Alliance. Support for anti-nuclear movement from Gov. Brown.
Forms of mobilization:Development of a network/collective action
Public campaigns
Artistic and creative actions (eg guerilla theatre, murals)
Involvement of national and international NGOs
Lawsuits, court cases, judicial activism
Media based activism/alternative media
Objections to the EIA
Street protest/marches
Creation of alternative reports/knowledge
Occupation of buildings/public spaces
Development of alternative proposals
Official complaint letters and petitions
Strong defence of the abalone (phylum Mollusca, a group which includes clams, scallops, sea slugs, octopuses and squid) and of the scenic beauty of the site. Massive demonstrations, many arrests after civil disobedience, during the building period in the 1970s and early 1980s.
Shareholder/financial activism.
Boycotts of official procedures/non-participation in official processes


Environmental ImpactsVisible: Loss of landscape/aesthetic degradation, Other Environmental impacts
Potential: Biodiversity loss (wildlife, agro-diversity), Fires, Soil contamination, Surface water pollution / Decreasing water (physico-chemical, biological) quality, Groundwater pollution or depletion, Large-scale disturbance of hydro and geological systems, Reduced ecological / hydrological connectivity
Other Environmental impactsOnce-through cooling systems allow coastal nuclear power plants to directly take in and discharge massive amounts of sea water -- causing significant damage to marine creatures and the environment.
Health ImpactsVisible: Exposure to unknown or uncertain complex risks (radiation, etc…)
Potential: Other environmental related diseases
Socio-economical ImpactsVisible: Loss of landscape/sense of place
Other socio-economic impactsProduction of nuclear waste over many decades


Project StatusStopped
Conflict outcome / response:Criminalization of activists
Negotiated alternative solution
Project cancelled
Many arrests of activists took place at the time the two nuclear units were built
Do you consider this an environmental justice success? Was environmental justice served?:Not Sure
Briefly explain:It took very long for the opponents of nuclear energy to achieve success in the sense of stopping the plant - however, the PG&E company closed down Diablo Canyon when it is still had a good chance of extending its licence. The proposal for shortening the plant's lifespan was negotiated with unions and environmentalists. The decommissioning will be expensive. Nuclear waste remains in situ.

Sources & Materials

(1) Nuclear power's last chance in California? by Rob Nikolewski (San Diego Union Tribune, 4 June 2016).

Los Angeles Times, PG&E to close Diablo Canyon, California's last nuclear power plant, Ivan Penn and Samantha Masunaga, 21 June 2016

(2) Forbes, Jul 15, 2016, Closing Diablo Canyon Nuclear Plant Will Cost Money And Raise Carbon Emissions, by James Conca.

(3) It'll take time — and $3.8 billion — to shut down the Diablo Canyon nuclear power plant, Los Angeles Times, Rob Nikolewski, 22 June 2016

Related media links to videos, campaigns, social network

(5) Timeline of the struggle on Diablo Canyon by Friends of the Earth 1958-2012

(4) The Diablo Canyon Timeline (until 1981) .This is the archival site for the Abalone Alliance.

Dark Circle, documentary film (Mothers for Peace, Abalone Alliance, the blockade of 1981 etc.)

A QUESTION OF POWER (1986) is a moving and informative documentary history of the nuclear power controversy and the U.S. antinuclear power movement. Narrated by Peter Coyote, the film focuses on 35 years of grassroots opposition to the “peaceful atom” in California, where the antinuclear power movement was born (in 1959-64 over the proposed Bodega Bay Atomic Park), and reached its peak in 1981 with the protests over the Diablo Canyon Nuclear Power Plant.

Meta information

Last update18/08/2019




The Diablo Canyon blockade