We’ve lived in a nuclear evacuation zone long enough. It’s time to close Diablo Canyon

There’s a misguided effort by some to keep Diablo Canyon nuclear plant operating beyond the closure dates of 2024 and 2025. This date was set by PG&E and approved by the California Public Utilities Commission. Additional years of operation would generate more radioactive waste, exacerbate the climate crisis and expose residents to additional years of health risks.

Don’t believe the myth that nuclear is carbon free. The fuel cycle of mining, milling, enriching and transporting uranium produces carbon dioxide. Construction and decommissioning activities are heavy carbon dioxide emitters.

There is no guarantee of reliable baseload power from a 40-year-old nuclear plant. Unit 2’s failed main generator was replaced in 2019 but failed again in 2020 and was online only 30% of the time that year. The complex and costly repairs of aging systems are likely to multiply in the ensuing years.

The spent fuel pools are overcrowded to at least three times their original capacity. A “beyond design” earthquake (think Fukushima) could crack the pools, cause water to leak out, and the spent fuel could spontaneously ignite — the most unimaginable catastrophe possible. This is a “low probability, high consequence” scenario, and it’s not included by the NRC in its spent fuel pool safety analysis because “it won’t happen.” We hope not.

Seasoned, highly skilled workers are retiring and moving on, resulting in loss of institutional knowledge about the unique idiosyncrasies of Diablo Canyon.

If the lifetime of the nuclear plant were extended, a new radioactive waste storage facility would have to be constructed to accommodate the additional wastes. With no federal repository, it’s likely to be stored on our fragile, seismic-prone coastline beyond any foreseeable future.

Diablo Canyon circulates 2.5 billion gallons of seawater every 24 hours in a system responsible for 80% of the loss of marine life on the California Coast. This system is no longer allowed in California, but the State Lands Commission made an exception for Diablo, allowing it to continue until the expiration of its operating licenses. If Diablo stayed open past 2025, PG&E would have to construct a costly alternative cooling system.

The seawater intake structure is vulnerable to rising levels of ocean water brought on by global climate change. This is the water that cools the plant. During seawater’s circulation through the facility, it warms by 19°F before being discharged back into the ocean, contributing to ocean warming. Think about it: 2.5 billion gallons every single day for 40 or more years. The math and the impacts are almost incalculable.

Diablo Canyon is situated at the nexus of at least 13 earthquake faults. Two of these, the Hosgri Fault and the Los Osos Fault, are classified by the U.S. Geological Survey as “major” and “active.” Keeping Diablo Canyon operating beyond its planned closure is playing Russian roulette.

We can do better. People of the Central Coast have tolerated living in a nuclear evacuation zone for four decades. Nuclear energy is dirty and dangerous. Diablo needs to close on the dates agreed upon by PG&E and the state of California.

Jane Swanson and Linda Seeley are spokespersons for San Luis Obispo Mothers for Peace.