PUC declines to admit confidential Comanche 3 root‑cause appendix and preserves it as an offer of proof

A dispute over late‑filed Comanche 3 materials dominated a portion of the Public Utilities Commission hearing, as intervenors sought to admit a June 2026 update to the utility’s Comanche materials and the company objected to admitting a newly filed confidential root‑cause analysis.

UCA lawyer Mr. Bunker told the commission UCA had filed five Comanche‑related documents and asked that the June 2026 report, its confidential root‑cause appendix and the large‑load forecast be admitted so parties could cross‑examine and the record would include the newest available information. Company counsel objected, saying the confidential appendix had been filed late, raised foundational and technical questions that would require experts to explain, and risked prejudicing the company because other parties had not had time to review or respond.

Commission staff agreed the body of the report could be considered, but the root‑cause appendix — a technical confidential file — lacked procedural opportunity for the company to present witnesses to explain conclusions and for intervenors to test them. The commission refused to formally admit the confidential root‑cause appendix into evidence during this hearing but, after discussion, preserved the confidential document as an offer of proof (administrative record item) so it will be available for appellate or later prudence review consideration.

Commissioner questions and party statements made clear that prudence and replacement‑power issues tied to the Comanche outage will be handled in a separate, later proceeding. Several parties noted the settlement before the commission contains a Comanche‑related performance framework and a suggested $30 million consequence tied to outages; the prudence review will determine whether any historical outage costs are recoverable in future rider or rate proceedings.

Representative quotes:
"This root‑cause analysis is highly relevant," UCA said; company counsel responded that the file was technical, late and lacked witnesses to lay foundation. The Commission preserved the confidential root‑cause report as an offer of proof but did not admit it into the evidentiary record at this hearing.

What happens next: The commission left the record intact and signaled that detailed prudence review of Comanche outage costs and replacement‑power modeling will be addressed in a separate docket when the company files its application.