Diablo Canyon reactors timeline

May 26, 1958: PG&E proposes construction of first reactors at Bodega Bay
Pacific Gas & Electric Co. announces plans to build the nation's first "commercially viable" nuclear power plant near Bodega Bay, a fishing village on the Pacific coast 50 miles north of San Francisco.

May 26, 1958-Oct 30, 1964: California resists
Opposition to the Bodega Bay plant swells from the public, press and elected officials in the first anti-nuclear power campaign in the U.S. and what historians consider the birth of California's modern environmental movement.

Oct. 30, 1964: PG&E gives up on Bodega Bay
After five years of grassroots organizing, protests, editorials, lawsuits and scientific studies, capped by the discovery that a branch of the San Andreas Fault runs through the site -- PG&E stops construction on the plant.

Feb. 27, 1963 – 1965: Site selection continues
Thwarted in Bodega Bay, PG&E purchases a tract in the Nipomo Dunes, south of San Luis Obispo, with plans for up to five reactors. After the Sierra Club, which had split over Bodega Bay, opposes the Nipomo Dunes site, PG&E agrees to sell the land to the state for a park and look elsewhere.

Feb. 1965: Diablo Canyon
PG&E picks Diablo Canyon, on the coast 12 miles west of San Luis Obispo, surrounded by three known earthquake faults, including the San Andreas Fault.

April 1968: Construction permit is granted for Diablo Canyon Unit 1
PG&E receives a construction permit for Reactor Unit 1 from the U.S. Atomic Energy Commission, precursor to the Nuclear Regulatory Commission. PG&E tells state and federal authorities that it expects to spend $188 million to construct Unit 1.

July 1969: Friends of the Earth forms, Diablo Canyon is first campaign
After failing to get the Sierra Club to reverse its support for Diablo Canyon, David Brower resigns as executive director. He forms Friends of the Earth, and the organization makes the fight against Diablo Canyon its first campaign.

Dec. 1970: PG&E receives construction permit for Diablo Canyon Unit 2
The Atomic Energy Commission gives PG&E a construction permit for Reactor Unit 2. The utility estimates that Unit 2 will be built at a cost of $192 million.

1971: Seismic shock- Hosgri Fault identified
Petroleum geologists reveal a previously unknown fault, the Hosgri Fault, less than three miles from the Diablo Canyon site. While the reactors were designed to withstand an earthquake of magnitude 6.75, the Hosgri Fault appears capable of generating a much larger 7.5 magnitude quake. The geologists publish their findings in the American Association of Petroleum Geologists Bulletin, and it receives little attention.

Nov. 15, 1973: Mothers intervene
Mothers for Peace, which was formed in 1969 in San Luis Obispo in opposition to the Vietnam War, shifts its focus to opposing Diablo Canyon as the war ends. Mothers for Peace files as an intervener in the licensing case.

Nov. 1973: Earthquake education
A report in the Los Angeles Times makes the existence of the Hosgri Fault a matter of public record and concern. PG&E says it learned of the fault a year earlier but did not inform the public or the Atomic Energy Commission.

Aug. 1977: Abalone Alliance
Seventy groups come together to form the statewide Abalone Alliance to fight Diablo Canyon and other nuclear power projects. The coalition stages its first blockade at Diablo Canyon in August 1977.

March 28, 1979: Three Mile Island
The Three Mile Island nuclear reactor in Pennsylvania suffers a partial meltdown, setting off a national outcry against nuclear power. Gov. Jerry Brown calls for a moratorium on construction of Diablo Canyon.

June 30, 1979: Gov. Brown opposes Diablo
An Abalone Alliance rally near the plant draws 40,000 people. At the rally, Gov. Brown comes out against its opening.

Sept. 15, 1981: Occupy Diablo!
Abalone Alliance mounts a two-week occupation of the site. Almost 2,000 protesters are arrested, the largest number ever arrested for civil disobedience in the United States.

Sept. 27, 1981: Backwards blueprints
After work is completed on structural supports to increase earthquake safety in response to the discovery of the Hosgri Fault, an engineer discovers that the supports for Unit 2 were installed backwards as a result of reversed blueprints.

March 26, 1984: Quality assurance problems
NRC staff engineer Isa Yin testifies that he does not believe that Diablo Canyon Unit 1 should be allowed to go critical due to a breakdown in quality assurance for the plant’s piping. His testimony directly contradicts that of his superiors and he tells the media: "They didn't bother to read my report." Yin later resigns to protest the NRC’s handling of safety issues.

Nov. 2, 1984: Unit 1 operating license
The Nuclear Regulatory Commission issues a license to the Unit 1 reactor for operation until November 2, 2024.

Aug. 26, 1985: Unit 2 operating license
The NRC issues a license to the Unit 2 reactor for operation until August 26, 2025. Massive cost overruns mean that the two reactors have not been completed at the original estimate of hundreds of millions of dollars but at some $5.52 billion.

Jan. 10, 1985: Evacuation planning scandal
KRON-TV in San Francisco reveals secret transcripts showing that the Nuclear Regulatory Commission illegally granted Diablo Canyon a license without properly reviewing evacuation plans.

Oct. 17, 1989: Seismic scare
The San Andreas Fault triggers a magnitude 6.9 earthquake, centered about 150 miles north of Diablo Canyon, killing 63 people and causing $6 billion in damage. The following spring, the U.S. Geological Survey says the Hosgri Fault near Diablo Canyon is a thrust fault capable of triggering a similar earthquake .

Feb. 5, 1997: Whistleblower warning
A Diablo Canyon whistleblower named Neil Aiken testifies before the Independent Safety Committee that PG&E's "focus on profits ... has created an environment in which safe operation is being jeopardized." Instead of taking him seriously, the utility tries to brand the control room operator as mentally ill.

March 22, 2004: Nuclear waste buildup
The Nuclear Regulatory Commission gives PG&E permission to build an “Independent Spent Fuel Storage Installation” to hold up to 2100 metric tons of spent reactor fuel that will not fit in Diablo Canyon’s spent fuel pools. This facility stores spent fuel in passively cooled dry casks which are safer than storing spent fuel in cooling pools but still vulnerable to terrorist attacks. San Luis Opisbo Mothers for Peace and Dr. Gordon Thompson alert the NRC to the potential for an attack on the spent fuel facility.

Nov. 21, 2008: A new fault is discovered
PG&E informs the Nuclear Regulatory Commission that USGS geophysicist Jeanne Hardebeck has discovered yet another previously unknown fault less than a mile from the Diablo Canyon plant. Dr. Hardebeck says the Shoreline Fault is likely connected to the Hosgri Fault and that together they could produce ground motion greater than that which Diablo Canyon was built to withstand.

Nov. 24, 2009: 20 more years?
PG&E applies to the Nuclear Regulatory Commission for 20-year license renewals for both reactors, which, if granted, would allow the then 40 year-old reactors to operate for an additional 20 years, to 2044 and 2045 respectively, rather than their originally agreed closure dates in 2024 and 2025.

Oct. 2010: Reactors in hot water
California enacts 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 creatues and the environment. While all plants are supposed to comply with the policy by 2015, Diablo Canyon is given the opportunity to instead explain by 2015 why they should not comply with the policy or face compliance by 2024. As Diablo Canyon causes some 80 percent of the damage to the marine environment of all the coastal power plants combined, excluding Diablo from the OTC policy would make a mockery of the program

March 11, 2011: Fukushima
An earthquake and tsunami hit the reactors at the Fukushima Dai-ichi nuclear power plant in Japan. The earthquake and resultant loss of power at the site leads to loss of coolant in the reactors’ cores and triggers three meltdowns. Some 160,000 people are evacuated within 50 kilometers and thousands more do so voluntarily. Ultimately, it is estimated that as much as 8 percent of the landmass of Japan, or over 18,000 square miles, has been contaminated and cost estimates of the damage reach an estimated $250 billion.

March 17, 2011: Emergency cooling failure
In the wake of the disaster at the Fukushima nuclear plant in Japan, the Union of Concerned Scientists reports that for 18 months in 2008 and 2009, Diablo Canyon's emergency cooling system was accidentally turned off.

April 10, 2011: Seismic slowdown
PG&E asks the Nuclear Regulatory Commission to delay consideration of Diablo Canyon’s license renewal until comprehensive seismic safety studies are completed. The utility says it will complete the studies by December 2015.

March 12, 2012: Lessons from Fukushima
The NRC informs reactor operators that they must re-evaluate seismic threats and preparations. Reactor operators must submit seismic hazard analyses to the NRC by March 2015.

Feb. 19, 2014: Contract questions
The chairman of the California Public Utilities Commission tells PG&E that, before its ratepayer contract is reviewed for possible extension, the utility must justify the cost effectiveness of electricity from the plant in light of the billions of dollars that must be spent on seismic studies, a solution to the once-through cooling problem, waste disposal and other safety concerns.

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