Sienna Solar and Storage Project
5 Documents in Project
Summary
SCH Number
2022080518
Lead Agency
San Bernardino County
Document Title
Sienna Solar and Storage Project
Document Type
NOD - Notice of Determination
Received
Posted
10/28/2025
Document Description
99MT 8ME, LLC (Applicant) plans to construct and operate the Sienna Solar and Storage Project(Project), a utility scale, solar photovoltaic (PV) electricity generation facility that would produce up to 525 megawatts (MW) of solar power and include up to 525 MW of energy storage capacity rate in a battery energy storage system (BESS) within an approximately 1,854-acre Project site. . Energy generated by the Project will be transmitted to Southern California Edison's (SCE) electric grid via an inter-connection with the proposed SCE Calcite Substation.
Contact Information
Name
David Mack
Agency Name
San Bernardino County
Job Title
consultant planner
Contact Types
Lead/Public Agency
Phone
Name
99MT 8ME
Agency Name
99MT 8ME LLC
Job Title
-
Contact Types
Project Applicant
Phone
Email
Location
Cities
Unincorporated Lucerne Valley
Counties
San Bernardino
Regions
Southern California, Unincorporated
Cross Streets
Northside Road and Barstow Road
Zip
92356
Total Acres
1854
State Highways
Highway 247
Notice of Determination
Approving Agency
San Bernardino County
Approving Agency Role
Lead Agency
Approved On
County Clerk
San Bernardino
Final Environmental Document Available at
https://lus.sbcounty.gov/planning-home/environmental/desert-region/
Determinations
(1) The project will have a significant impact on the environment
Yes
(2a) An Environmental Impact Report was prepared for this project pursuant to the provisions of CEQA
Yes
(2b) A Mitigated or a Negative Declaration was prepared for this project pursuant to the provisions of CEQA
No
(2c) An other document type was prepared for this project pursuant to the provisions of CEQA
No
(3) Mitigated measures were made a condition of the approval of the project
Yes
(4) A mitigation reporting or monitoring plan was adopted for this project
Yes
(5) A Statement of Overriding Considerations was adopted for this project
Yes
(6) Findings were made pursuant to the provisions of CEQA
Yes
Attachments
Notice of Determination
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