CPUC staff outline SB 884 project-data template, require RRU IDs and two alternative mitigations

California Public Utilities Commission staff on May 30 presented a draft data template and guideline for SB 884 electrical undergrounding project lists and fielded stakeholder questions about identifiers, backcasting and how the ICE reliability calculator will be used.

The template requires a Risk Reporting Unit (RRU) identifier, an OEIS project ID and an "undergrounding alternative mitigation" field as primary keys linking tables that collect project characteristics, cost breakdowns, risk-model change history and reliability monetization inputs. Staff said each RRU row must be submitted for the undergrounding mitigation and for each of two alternative mitigations, producing three rows per RRU for comparative analysis.

The requirement matters because it is intended to make utility submissions traceable, auditable and comparable across phase 2 applications and subsequent progress reports, CPUC staff said. The template also includes fields for backcasted values so progress-report numbers can be compared to what would have been reported under the RRU structure at the time of the original filing.

CPUC staff framed the template as aligning with the risk‑based decision (RDF) proceeding and Energy Safety guidance. Matthew Rapelson, a consultant working with CPUC staff, said the RRU "is designed to allow accurate aggregation" to program-level filings such as an Electrical Undergrounding Plan (EUP). Rapelson and staff emphasized that the naming schema for RRUs should be short, transparent and avoid reuse.

Staff walked through six tables in the draft template. Table 1 collects RRU identifiers, mitigation plans, pre‑ and post‑mitigation risk and backcasted fields. Table 2 captures disaggregated capital and operating costs (labor, materials, permits, environmental and other). Table 3 is a risk-model change tracker to document how model or asset-definition changes alter risk scores. Table 4 records associated lower‑risk assets (for example, secondary or service lines) and miles in high‑fire-threat districts (HFTD). Table 5 collects financial inputs, including the three discount rates required by phase‑3 decision d240564, a value of statistical life (VSL) and present value revenue requirement (PVRR). Table 6 gathers the inputs used with the ICE reliability calculator to estimate dollar value per customer‑minute interrupted (CMI) by operational division and HFTD tier.

Staff said utilities must record the ICE calculator version used in submissions because the ICE tool is expected to be updated. Stakeholders asked whether the draft assumes ICE v1 fields that are not present in a newer ICE v2 and whether alternative granularities would be allowed. Staff answered that the draft reflects draft ICE inputs and that the template will be updated if ICE v2 differs; staff said they currently prefer a common granularity across utilities to support consistent comparison but had no final determination on flexibility.

Questions from utility and industry participants focused on backcasting and traceability. Stakeholders asked when backcast fields are required and how CPUC expects a utility to compare project‑level filings to later subproject or RRU‑level reports. Staff replied that backcasting is intended to enable apples‑to‑apples comparisons when a utility reports at a coarser project level in its phase‑2 application and later reports at subproject/RRU granularity in progress reports; the backcast fields bridge those differences.

Participants also asked how filings should reference prior proceedings and funding requests. The template includes a table‑level field labeled "filings" that asks utilities to list relevant filings (advice letters, petitions for modification or other filings) where the project is reported or budgeted. Stakeholders sought clarification about whether that requirement is limited to EUP‑funded work or applies more broadly; staff acknowledged the need to clarify and said they would follow up.

No formal votes or commission actions were taken at the workshop. Staff indicated this was an early draft and said further technical working groups are scheduled, including an ICE‑focused workshop on June 24 and a follow‑up technical working group on June 10; staff also said final guideline timing remains under internal development.

The session closed with staff inviting written interpretations and suggested edits in advance of the next workshop and with participants recommending numerical examples for CBR and ICE calculations to clarify how wildfire ignition and outage‑program benefits should be combined in numerator calculations.

The CPUC presentation and Q&A clarified the draft template's structure and flagged several open questions—ICE version compatibility, the exact use of backcasting, the scope of the "filings" field and acceptable granularity. Staff asked stakeholders to provide written feedback ahead of the next technical working group so the template can be revised and updated before it is finalized.