Horizon has provided the California Public Utilities Commission (CPUC) with CEQA, NEPA and regulatory compliance services since 2013. CPUC conducts environmental assessments of projects proposed by utility applicants. Projects proposed by utility applicants are defined as work related to the application of any Investor Owned Utility for either a Permit to Construct or a Certificate of Public Convenience and Necessity.

Services provided by Horizon include:

  • Reviewing CEQA/NEPA documents prepared by state and federal agencies.
  • Preparing CEQA documents and mitigation monitoring plans.
  • Providing construction monitoring services.
  • Coordinating public notices and meetings.
  • Providing expert witness testimony.


Examples of Horizon’s CPUC work include the following:

EIR for NextEra Energy Transmission West Suncrest Dynamic Reactive Power Support Project.

The project in San Diego County involves construction of a dynamic reactive facility approximately 1 mile east of the existing Suncrest Substation and interconnecting this facility with the substation via an underground transmission line. Horizon prepared the EIR and responded to hundreds of pages of comments received during the public review period.

CEQA Compliance for Pacific Gas & Electric/NextEra Energy Transmission West Estrella Substation Project.

Horizon prepared a Draft Environmental Impact Report (EIR) for the California Public Utilities Commission (CPUC) for the proposed Estrella Substation and Paso Robles Area Reinforcement Project. The Draft EIR was published in December 2020. The Project is proposed by Horizon West Transmission, LLC, and Pacific Gas and Electric Company.

The Proposed Project would involve construction and operation of a new 230 kilovolt (kV)/70 kV substation and a new approximately 7-mile-long 70 kV power line, and replacement/reconductoring of approximately 3 miles of an existing 70 kV power line. The Proposed Project would also provide for the future establishment of three new distribution feeders from the proposed Estrella Substation, including construction of roughly 1.7 miles of new distribution lines in unincorporated San Luis Obispo County and within the City of Paso Robles.

The Proposed Project is intended to address identified deficiencies in the electrical grid system in the Paso Robles area and to accommodate projected new growth. The Proposed Project is needed to provide transmission system redundancy and power support in the event of outages, as well as increased distribution capacity to accommodate forecasted electrical load growth in the Paso Robles area.

In addition to the Proposed Project and the No Project alternative, the Draft EIR evaluated eight project alternatives at an equal level of detail.


CEQA Compliance for SDG&E Tie Line 649 Wood-to-Steel Replacement Project.

Horizon prepared an IS/MND for project involving replacement of San Diego Gas & Electric’s existing wood poles with steel poles to reduce the likelihood of service disruption along tie line 649 (7-mile-long alignment) in the event of a wildland fire.

NEPA/CEQA Compliance for Winterhaven Last Mile Underserved Broadband Project. Horizon prepared an environmental assessment for a project that will extend high-speed internet service to approximately 15 square miles covering the Winterhaven Community and other areas of unincorporated Imperial County, including the Yuma-Quechan Indian Reservation.

CEQA Compliance for Control Silver Peak

The Control-Silver Peak subtransmission line alignment extends approximately 42 miles from the Control Substation in Inyo County near the City of Bishop, to the Fish Lake Valley Metering Station in Mono County at the California-Nevada border. An additional 16-mile section runs from north central Inyo County through Chalfant Valley to supply power to the Zack Substation in south central Mono County, and an additional 2.4-mile section provides power to the Deep Spring Substation in northeastern Inyo County.Horizon is assisting the California Public Utilities Commission (CPUC) with environmental review of the Control-Silver Peak Project (Proposed Project), which is part of the Southern California Edison (SCE) Transmission Line Rating Remediation (TLRR) Program to bring circuits into compliance with CPUC General Order 95 (e.g., meeting minimum clearance distances between powerlines and the ground surface). SCE identified clearance problems on the 55 kilovolt (kV) subtransmission lines that comprise the Proposed Project.

The Proposed Project includes rebuilding approximately 39 miles of the existing 55 kV subtransmission system (i.e., replacement of poles and conductor), with additional work on smaller portions of the remaining 21 miles of the alignment (e.g., addition of ground wiring). The majority of the project alignment occurs within the Inyo National Forest and also on Burea of Land Management (BLM) land in the White Mountains. BLM is the federal lead agency for the Proposed Project.

In support of the CPUC’s CEQA process, Horizon has completed a pre-filing review of SCE’s proponent’s draft environmental assessment (PEA) for deficiencies prior to SCE’s formal application submittal; has held initial project review meetings with key agency stakeholders including the U.S. Forest Service, both Inyo and Mono Counties, and the City of Bishop; and has conducted initial outreach meetings with local tribes in advance of AB 52 consultation. Horizon will prepare an environmental impact report (EIR) for the CPUC upon SCE’s formal application and submittal of a final PEA, anticipated in 2021. Horizon is also assisting with environmental coordination with the BLM, the NEPA lead agency. Key issues to be considered in the EIR will include project construction access and staging in remote steep terrain and potential impacts on biological, cultural, and forest resources resulting from Project construction. Potential operational impacts to aesthetics as a result of new steel poles and viewsheds will also be considered.

Following project approval, Horizon will also assist the CPUC with construction compliance monitoring to ensure that mitigation measures identified in the EIR are properly implemented during construction activities.



On-Call Environmental Consulting Support for Electric and Gas Projects (since 2013)

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