Diablo Canyon Nuclear Powerplant: 5-Year CDP & 20-Year Federal Consistency

The Commission approved PG&E's coastal development permit and federal consistency determination for extended operations of Diablo Canyon Nuclear Power Plant through October 2030, conditioned on a significantly enhanced mitigation package than what PG&E proposed at the November hearing. The improvements, while still falling short of the immediate conservation of all 12,000 acres of Diablo Canyon Lands that ActCoastal and many others demanded, lay out a feasible pathway to achieve full conservation over time. These significant enhancements would not have been possible without the work of Senator John Laird, Assemblymember Dawn Addis, tribal voices, a wide range of coastal advocates, and a united front from Coastal Commissioners at last month's hearing demanding PG&E fully conserve the Diablo Canyon Lands before earning their vote.

Why Mitigation? 

Diablo Canyon's once-through cooling system withdraws approximately 2.5 billion gallons of seawater daily, entraining marine organisms, eggs, larvae, and early life stages across a source water area equivalent to more than 14 square miles of nearshore coastal ecosystems. Commission staff acknowledged that even with the approved mitigation package, the project cannot achieve full consistency with Coastal Act Sections 30230 and 30231, which require the protection of marine biological productivity.

‍Key Improvements in PG&E's Mitigation Package

Below is a brief summary of the improvements, compared to what PG&E initially proposed at the November hearing.

North Ranch: Conservation easement expanded from 1,100 to 4,500 acres, covering virtually the entire area except ~100 acres needed for plant security. Would expand Montaña de Oro State Park by over 50%.

Wild Cherry Canyon: Excluded entirely from the initial mitigation offer, now included with an immediate purchase option for ~2,200 acres available to government agencies, nonprofits, or California Native American Tribes who also acquire HomeFed's leasehold interest. Option expires October 2030, then converts to right of first refusal.

South Ranch: Initially excluded, now includes a 1,290-acre deed restriction on all coastal zone lands plus right of first refusal for all 5,000 acres with required conservation easement upon purchase. Available to government agencies, nonprofits, and California Native American Tribes.

Public Access Trails: Expanded from 10 to 25 miles with new "through-trail" connecting Montaña de Oro to Port San Luis, plus extended Point Buchon and Pecho Coast Trail loops. Funding increased from $5.6 million to $10 million.

Tribal Equity: Last-minute hearing amendments added nonprofits and California Native American Tribes to equal standing with government agencies for North Ranch and Wild Cherry Canyon acquisition, correcting the previous inconsistency where tribes had equal standing only for South Ranch.

Extended Timelines: South Ranch right of first refusal exercise period extended from 180 days to 12 months, with termination date extended to December 31, 2040, providing realistic timeframes for complex conservation transactions.

The Vote

After several hours of public comment and hard questioning between Commissioners, Commission staff, and PG&E's representatives, a majority of Commissioners felt the enhanced mitigation package was sufficient to approve continued DCPP operations. The Commission voted 9-3 to approve PG&E's CDP for another 5 years of operations and to certify federal consistency for up to 20 years of continued operations. Commissioners Jackson, Escalante, and O'Malley (alternate for Bochco) dissented on the grounds that full, binding conservation of all 12,000 acres of Diablo Canyon Lands had not been achieved.

‍

‍

ActCoastal applauds the Commissioners for demanding a stronger mitigation package from PG&E. PG&E's spokesperson deflected and demurred in November over why more robust conservation would not be possible, only to return a month later offering the very things he previously claimed were infeasible. The Commission's tough negotiating resulted in real and lasting conservation improvements that will be enjoyed for generations in San Luis Obispo County.

However, the mitigation still fell short of what ActCoastal called for. Full and immediate conservation of all 12,000 acres of Diablo Canyon Lands was not achieved. More critically, we urged the Commission to require the entire mitigation package be calibrated to the 5-year CDP period, not the 20-year federal consistency review period. The divergence stems from a mismatch: while the state legislature has only authorized DCPP operations until 2030, PG&E's application to the Nuclear Regulatory Commission seeks a 20-year federal license. Staff used this longer federal timeline to justify evaluating—and effectively pre-approving—mitigation for two decades of operations. We disagree with staff's assertion that this approach was legally required.

As approved, PG&E must return for another CDP if the state legislature allows DCPP operations to continue beyond 2030, but the Commission's ability to demand additional mitigation will be severely constrained. Commission staff explicitly stated they "anticipate" such future review would be "expedited" and that "additional or different mitigation would not be required"—essentially pre-approving mitigation for 20 years of operations when only 5 years are currently authorized. Meanwhile, PG&E is positioned to receive roughly $2 billion in corporate incentives and fees over the five-year extension period, while ratepayers bear the risk of rising operational costs and potential loan defaults.

The Coastal Act demands full mitigation to the maximum extent feasible for DCPP's ongoing destruction of coastal ecosystems. PG&E's financial position would allow them to provide all available mitigation immediately for the authorized 5-year period, and to provide additional mitigation in 2030 if operations continue beyond that date. Therefore, we count this an Anti-Coast vote despite the significantly improved mitigation package.

‍