SMARA Mineral Land Classification

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San Rafael Rock QuarryCalifornia's Surface Mining and Reclamation Act of 1975 (SMARA) requires the State Geologist to classify land into mineral resource zones based on the known or inferred mineral resource potential of that land. The primary goal is to ensure that important mineral resources do not become inaccessible due to uninformed land-use decisions.

To this end, the California Geological Survey performs objective mineral land classification (MLC) to assist in the protection and wise development of California's mineral resources. The MLC process is based solely on geology, without regard to existing land use or land ownership.

MLC Maps and Reports

The primary products of CGS mineral land classification are maps and reports. Local agencies are required to use the classification information when developing land-use plans and when making land-use decisions. This section provides access to our collection of over 200 MLC products.

Information Warehouse MLC Portal

The CGS Information Warehouse: Mineral Land Classification Portal is our most comprehensive collection of MLC products. It provides a convenient map interface for viewing MLC petitions and study areas, and for finding and downloading MLC reports and maps in portable document format (PDF).

MLC Publications Index [updated August 2020]

Publications o​​f the SMARA Mineral Land Classification Project Dealing with Mineral Resources in California is a printer-friendly list of all mineral land classification reports produced by the California Geological Survey. We've updated the list to include reports published after 2013, and added a 1977 report (OFR 77-16) that wasn’t on the previous list.

[Recent Release] Special Report 245 - Mineral Land Classification: Concrete Aggregate in the Greater Sacramento Area Production-Consumption Region

Preview of SR 245 Plate 1, which is a map of the Greater Sacramento Area Production-Consumption Region. Opens a larger image in a new Matt D. O'Neal and Fred W. Gius

NOTE: SR 245 is a new release that is not yet available through our Information Warehouse MLC Portal.

Summary of SR 245

Urban expansion in the Greater Sacramento Area Production-Consumption (P-C) Region threatens to preclude mineral resource extraction. At present, the P-C Region contains sufficient concrete aggregate resources to meet the projected 50-year demand. However, there is a substantial and important disparity between the geographic distribution of mineral resources and population centers. Only a minor proportion of resources are located near population centers. Utilization of more distant resources results in a significant increase in cost to the aggregate consumer, road wear and tear, traffic congestion, greenhouse gas emissions, and air pollution. For example, each additional mile of aggregate transport costs 15 cents per ton, and one mile of a six-lane highway consumes more than 110,000 tons of aggregate.

Special Report 245 and its associated plates (maps) are available as free downloads or as printed products. (NOTE: The plates measure 36 inches by 48 inches each.) To purchase printed copies, contact our Publications Sales Desk or visit the California Geological Survey Library in Sacramento.

PDFSpecial Report 245 - Mineral Land Classification: Concrete Aggregate in the Greater Sacramento Area Production-Consumption Region 2018 (2.6 MB PDF)

PDFSR 245 Plate 1: Mineral Land Classification Map (23 MB PDF)

PDFSR 245 Plate 2A: Resource Sector Map 1 of 2 (13 MB PDF)

PDFSR 245 Plate 2B: Resource Sector Map 2 of 2 (19 MB PDF)

Map Sheet 52 - Aggregate Sustainability in California (2018)

Preview of Map Sheet 52. Opens a larger image in a new John P. Clinkenbeard and Fred W. Gius

Background of Map Sheet 52

Sand, gravel, and crushed stone are “construction materials.” These materials, collectively referred to as aggregate, provide bulk and strength to portland cement concrete, asphaltic concrete, Class II base, and other aggregate commodities such as subbase, drain rock, and fill. Aggregate normally provides 80 to 100 percent of the material volume in these uses.

The building and paving industries in California consume large quantities of aggregate and future demand for this commodity is expected to increase throughout California. Aggregate materials are essential to modern society, both to maintain the existing infrastructure and to provide for new construction. Because aggregate is a low unit-value, high-bulk-weight commodity, it must be obtained from nearby sources to minimize economic and environmental costs associated with transportation. These factors make information about the availability and demand for aggregate valuable to land-use planners and decision makers charged with planning for a sustainable future for California’s citizens.

Map Sheet 52 was originally published in 2002 and subsequently updated in 2006 and 2012. Map Sheet 52 (2018) is an update of the version published in 2012. The estimates of permitted reserves, aggregate demand, and years of permitted reserves remaining are based on conditions as of January 1, 2017.

Summary of Map Sheet 52

Map Sheet 52 is a statewide overview of projected future aggregate needs and currently permitted reserves. The purpose of the map is to compare projected aggregate demand for the next 50 years with currently permitted aggregate reserves in various regions of the state. The map also shows the projected years of permitted reserves remaining and highlights regions where fewer than 10 years of permitted aggregate supply remain.

The following conclusions can be drawn from Map Sheet 52 (2018) and the accompanying report:

  • In the 30-year period from 1987 to 2016, Californians consumed an average of about 180 million tons of construction aggregate (all grades) per year or about 5.3 tons per person per year.
  • In the next 50 years, the study areas identified on Map Sheet 52 will need approximately 11 billion tons of aggregate.
  • The study areas currently have about 7.6 billion tons of permitted reserves, which is about 69 percent of the total projected 50-year aggregate demand identified for these study areas. This is about 10 percent of the total aggregate resources located within the study areas.

Comparing regional needs to available reserves and resources demonstrates the important aggregate resource issues facing lead agencies in California. These issues include the need to plan carefully for the use of lands containing these resources and the need to consider the permitting of additional aggregate resources before currently permitted deposits are depleted.

Map Sheet 52 and its companion report are available as free downloads or as printed products; prints are $25 each, plus $8 to cover shipping. (NOTE: the map measures 36 inches by 42 inches.) To purchase printed copies, contact our Publications Sales Desk.

PDFMap Sheet 52 - Aggregate Sustainability in California (2018) (4 MB PDF)

PDFMap Sheet 52 companion report (270 KB PDF)

NOTE: Aggregate reserves and projected aggregate demand shown on Map Sheet 52 are updated from mineral land classification reports published by CGS between 1979 and 2017. Although the statewide and regional information presented on the map and in the accompanying report may be useful to decision-makers, it should not be used as a basis for local land-use decisions. The more detailed information contained in each of the aggregate studies employed in the compilation of Map Sheet 52 should be used for local land-use and decision-making purposes.

MLC Guidelines and Petition Information

In addition to the state's self-initiated classification activity, individuals and organizations may petition the State Mining and Geology Board (SMGB) to classify mineral lands that are claimed to contain significant mineral deposits. For complete information, please see SECTION III. GUIDELINES FOR CLASSIFICATION AND DESIGNATION PETITIONS starting on page 9 of the SMGB's Guidelines for Classification and Designation of Mineral Lands.

The "Petition for Classification-Designation of Mineral Lands" form can be found in Appendix A of the aforementioned SMGB Guidelines document. For your convenience, the SMGB provides a standalone version of the Classification Petition form on their web site.

Completed Petitions should be sent to:

The California State Mining and Geology Board
Attn: Jeffrey Schmidt
801 K Street MS 20-15
Sacramento, CA 95814

Make Check payable to: The State Mining and Geology Board

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