Parties React to Safety Policy Division's Evaluation in the SoCalGas/SDG&E RAMP Proceeding

The following summary synthesizes all major stakeholder responses to the Sempra Utilities' (SoCalGas/SDG&E) 2025 Risk Assessment and Mitigation Phase (RAMP) filings, including the utilities’ own comments and those submitted by TURN, the Mussey Grade Road Alliance (MGRA), Cal Advocates, the Indicated Shippers, and the Small Business Utility Advocates (SBUA).

Driven by an August 11 scoping memo and Safety Policy Division (SPD) evaluation, these comments reveal how SoCalGas/SDG&E's risk models, tranching methodologies, mitigation-selection logic, and cost-benefit analyses are being scrutinized and challenged across the proceeding.

(For reference, SoCalGas's application is available here; SDG&E's application is available here.)

SoCalGas/SDG&E

The Sempra Utilities defend the overall structure and compliance of their 2025 RAMP filings, emphasizing that their risk models, scaling methodology, and alternative Homogeneous Tranching Method (HTM) are aligned with the CPUC’s Risk-Based Decision-Making Framework and reflect meaningful improvements in data quality, model sophistication, and wildfire/PSPS risk evaluation. The utilities express willingness to adopt many of the CPUC Safety Policy Division’s recommended refinements, such as:

• Clarifying cost-benefit ratio (CBR) calculations;
• Improving documentation;
• Increasing tranching transparency;
• Disaggregating risk categories; and
• Better aligning mitigation plans with risk outputs...

...while maintaining that their filings already meet regulatory requirements and appropriately prioritize high-consequence events. They highlight enhancements such as 24-hour unsuppressed fire modeling, improved physics-based probability-of-failure modeling, and more granular risk segmentation, and commit to integrating additional refinements into their upcoming Test-Year 2028 General Rate Case.

Meanwhile, every intervenor argues that substantial methodological, transparency, and analytical deficiencies remain. The intervenors identify common themes:

• Unexplained changes in risk scores;
• Insufficient justification for the Sempra Utilities' risk-scaling choices;
• Opaque mitigation-selection logic;
• Over-segmentation and misalignment in SDG&E’s wildfire and Public Safety Power Shutoff tranching; and
• Inconsistent or incomplete alternatives analyses.

INDICATED SHIPPERS

The Indicated Shippers concentrate on SoCalGas’s gas-side modeling, arguing that SoCalGas provides no adequate justification for drastic increases in LoRE (Likelihood of Risk Event)/CoRE (Consequence of Risk Event) values compared to the 2021 RAMP, and that risk-averse scaling can transform weak mitigations into apparently strong ones.

The Shippers strongly endorse SPD’s recommendation to require unscaled cost-benefit ratios and warn against ratepayer commitments to high-cost mitigations with unscaled cost-benefit ratios below 1.0. For Underground Gas Storage, the Shippers press the Commission to require field-specific risk segmentation, especially for aging, higher-risk facilities, and to ensure mitigation plans reflect those differences.

CAL ADVOCATES

Cal Advocates supports SPD’s findings and adds concerns about the Sempra Utilities' inconsistencies in mileage, cost, and benefit assumptions in undergrounding and covered conductor comparisons. Cal Advocates calls for corrected analyses and resubmitted cost-benefit ratio calculations.

Cal Advocates argues further that the utilities' modeling lacks adequate stability and documentation, and that meaningful decision-making requires more granular cost data and transparent explanations of how scaling and discount-rate assumptions influence mitigation choices.

TURN

TURN focuses on modeling weaknesses, especially in SDG&E’s wildfire and Public Safety Power Shutoff chapters. TURN argues that the utility’s revised tranching still fails to create genuinely homogeneous risk groupings, that historical risk reduction from past investments is omitted, and that SDG&E incorrectly ignores the mitigating effects of customer and facility backup power in PSPS consequences. TURN also warns that SDG&E’s fire simulations, without accounting for suppression, distort the risk landscape and potentially misguide mitigation spending.

MUSSEY GRADE ROAD ALLIANCE

MGRA extends TURN's critique by questioning the realism of SDG&E’s fire modeling, especially the 24-hour “unsuppressed burn” assumption that ignores Cal Fire’s operational success in containing the vast majority of fires. MGRA argues that this approach severely inflates the scale of potential wildfire consequences.

MGRA also challenges SDG&E’s cost-benefit transparency, especially for grid-hardening programs where primary and secondary infrastructure cost and risk data are lumped together, making it impossible for stakeholders to evaluate the true trade-offs between undergrounding, covered conductor, and other mitigations.

SMALL BUSINESS UTILITY ADVOCATES

SBUA argues that convex scaling may inflate catastrophic risk and systematically bias the Sempra Utilities' modeling toward capital-heavy projects that impose disproportionate rate impacts on small commercial customers. SBUA highlights the lack of tranche-to-mitigation traceability, warning that SoCalGas/SDG&E do not clearly demonstrate how individual risk tranches map to spending decisions.

SBUA supports further alternatives analysis (including vegetation management, non-infrastructure mitigations, and discrete Battery Electric Storage System safety risk modeling) and offer cautious support for the utilities' proposed Homogeneous Tranching Method while acknowledging SPD’s findings that HTM still fails to produce consistently homogeneous tranches in wildfire modeling.

INSTANT ANALYSIS: Collectively intervenors argue that the Sempra Utilities' risk modeling architecture remains too opaque, too volatile, and too dependent on mathematical transformations (especially convex scaling) to support confident, cost-effective mitigation planning.

• While SoCalGas and SDG&E defend the integrity of their RAMP submissions and commit to iterative refinements, every intervenor identifies the same structural problems: unexplained LoRE/CoRE inflation, misaligned or over-segmented tranching, unrealistic wildfire consequence modeling, weak alternatives analysis, and mitigation portfolios that appear optimized for scaled results rather than underlying, verifiable risk reductions.
• Practically speaking, the RAMP-to-General Rate Case pipeline may not yet be reliable as a foundation for billions in wildfire, PSPS, and gas-system spending. Stakeholders are effectively telling the CPUC: do not carry these models forward without correction.
• The CPUC must now either require the utilities to rerun key analyses with transparent, replicable assumptions (including unscaled CBRs and field-specific risk segmentation) or risk anchoring the 2028 GRC in models that (according to intervenors) obscure tradeoffs, inflate benefits, and make independent verification nearly impossible.