Gem Hill Quarry Project by CalPortland Company (PP21404)

6 Documents in Project


SCH Number
Lead Agency
Kern County
Document Title
Gem Hill Quarry Project by CalPortland Company (PP21404)
Document Type
NOP - Notice of Preparation of a Draft EIR
Present Land Use
Document Description
The project proponent has submitted: (a) a Conditional Use Permit (CUP 45, Map 214) application, to allow a surface mining operation and development of a reclamation plan on 82 acres of an approximately 210-acre reclamation plan boundary, which would utilize a 0.75-acre primary access road outside of such reclamation plan boundary to provide access to/from Mojave Tropico Road. Access to the site would be obtained via two access roads to Mojave Tropico Road, specifically the aforementioned access road and a secondary access road to the north thereof. The project proponent proposes to employ open pit, multibench, and drill and blast mining techniques to mine naturally occurring pozzolan (volcanic tuff), which is used in the production of cement. No crushing or processing of mined mined material would occur onsite. The life of the operation is proposed to be 30 years. Annual mineral production is estimated to be 500,000 tons, and the maximum total mineral production is estimated to be 15,000,000 million tons. The total anticipated production of mine waste (overburden) is estimated to be 600,000 tons, which would be disposed in two onsite overburden stockpiles. The proposed maximum depth of excavation is 300 feet below original grade. No phasing of mining is proposed. Maximum operational inter-bench slopes (also referred to as bench face slopes) for the quarry will be 0.25:1 (horizontal:vertical (H:V)) with overall slopes of 1:1 (H:V). Maximum final reclaimed inter-bench slopes for the quarry will be 0.25:1 (H:V). Overall final reclaimed slopes for the quarry will be a maximum of 1:1 (H:V). Maximum operational slopes for the overburden stockpiles will be 1.5:1 (H:V). Maximum and overall final reclaimed slopes for the overburden stockpiles will be 2:1 (H:V). Operations would typically be conducted between 7:00 a.m. and 7:00 p.m., Monday through Saturday, with the understanding that additional shifts or longer/alternative hours may be required due to operational constraints. As proposed, there would be a maximum of 20 employees onsite at any one time. These 20 employees would include haul truck drivers, who would haul overburden onsite (from the quarry to the overburden stockpiles), as well as hauling naturally occurring pozzolan (volcanic tuff) offsite to clients.

Contact Information

Randall Cates
Agency Name
Kern County Planning and Natural Resources Department
Contact Types
Lead/Public Agency


Cross Streets
Mojave Tropico Road & Backus Road
Total Acres
Parcel #
State Highways

Notice of Completion

State Review Period Start
State Review Period End
State Reviewing Agencies
California Air Resources Board (ARB), California Department of Fish and Wildlife, Central Region 4 (CDFW), California Department of Parks and Recreation, California Department of Resources Recycling and Recovery, California Department of Transportation, District 6 (DOT), California Department of Transportation, District 9 (DOT), California Department of Water Resources (DWR), California Energy Commission, California Governor's Office of Emergency Services (OES), California Highway Patrol (CHP), California Natural Resources Agency, California Regional Water Quality Control Board, Lahontan Victorville Region 6 (RWQCB), Department of Toxic Substances Control, Office of Historic Preservation, California Native American Heritage Commission (NAHC), California State Lands Commission (SLC), California Department of Conservation (DOC)
State Reviewing Agency Comments
California Native American Heritage Commission (NAHC), California State Lands Commission (SLC), California Department of Conservation (DOC)
Development Types
Mining (Mineral Pozzolan)
Local Actions
Use Permit
Project Issues
Aesthetics, Agriculture and Forestry Resources, Air Quality, Biological Resources, Cultural Resources, Cumulative Effects, Drainage/Absorption, Energy, Flood Plain/Flooding, Geology/Soils, Greenhouse Gas Emissions, Growth Inducement, Hazards & Hazardous Materials, Hydrology/Water Quality, Land Use/Planning, Mandatory Findings of Significance, Mineral Resources, Noise, Population/Housing, Public Services, Recreation, Schools/Universities, Septic System, Sewer Capacity, Solid Waste, Transportation, Tribal Cultural Resources, Utilities/Service Systems, Vegetation, Wetland/Riparian, Wildfire, Energy,


Draft Environmental Document [Draft IS, NOI_NOA_Public notices, OPR Summary Form, Appx,]
Notice of Completion [NOC] Transmittal form

Disclaimer: The Governor’s Office of Planning and Research (OPR) accepts no responsibility for the content or accessibility of these documents. To obtain an attachment in a different format, please contact the lead agency at the contact information listed above. You may also contact the OPR via email at or via phone at (916) 445-0613. For more information, please visit OPR’s Accessibility Site.

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