FROM AGGREGATE AVAILABILITY TO SUSTAINABILITY IN CALIFORNIA

California leads the nation in the production of sand and gravel, and ranks second behind Texas in the production of portland cement. Under the California Surface Mining and Reclamation Act of 1975 (SMARA), the State Geologist classifies mineral resources solely on geologic factors, and without regard to existing land use and land ownership. Following classification, the State Mining and Geology Board (SMGB) may consider “designating” such lands should the classified area contain mineral resources of regional or statewide economic significance and that may be needed to meet future demands. Maps and descriptions of the designated mineral lands were placed in the California Public Resources Code and officially transmitted to those lead agencies having permitting authority over those lands. CGS’s statewide Aggregate Availability Map, commonly referred to as Map Sheet 52, was developed in 2002 and updated in 2006. The purpose of Map Sheet 52 was to compare projected aggregate demand for the next 50 years with currently permitted aggregate resources in 31 “production-consumption” regions of the state, and flag regions where there were less than 10 years of permitted aggregate supply remaining. The 31 P-C aggregate study areas covered about 25 percent of the State’s geography, but about 90 percent of California’s population. It was shown that in the next 50 years, California was projected to need approximately 13.5 billion tons of aggregate. Map Sheet 52 demonstrated the need for additional permitting of mineral resources, but did not address the overall effectiveness of the state’s efforts to protect aggregate resources, or aggregate sustainability. To address the effectiveness of the state’s overall efforts to conserve and address aggregate sustainability, new maps are being considered. These maps may incorporate other factors to reflect the pace of urbanization, quality of the mineral resource, and environmental factors (i.e., sensitive habitat, wildlife refuge, etc.), material haul distances, infrastructure (suitability of roads and bridges) condition, and greenhouse gas emissions.