Naturally Occurring Asbestos in El Dorado County

Open-File Report 2000-02:

Areas More Likely to Contain Natural Occurrences
of Asbestos in Western El Dorado County, California

On May 12, 2000, the California Department of Conservation’s California Geological Survey (CGS) released an improved map showing areas where naturally occurring asbestos is more likely to be found in Western El Dorado County. Asbestos is a term used for several naturally occurring fibrous minerals, often (but not always) present in serpentine rocks. State, federal, and international health agencies have classified asbestos as a known human carcinogen. In 1998, CGS produced a smaller, less-detailed version of this map. In March 1999, a task force comprised of local, state and federal agencies recommended that DOC develop a series of more-detailed maps showing areas where asbestos is more likely to be found throughout California. Because of growing health concerns, western El Dorado County was selected as a "pilot project" for this effort.

The accompanying report discusses asbestos health issues, the history of the asbestos issue in El Dorado County, the geologic basis for the classification of units shown on the map, the methods used to produce the map, and limitations and recommended uses of these products. An evaluation of Landsat Thematic Mapper images for mapping is included as Appendix A. Appendix B is the current state law that permits creation of Geologic Hazard Abatement Districts—a mechanism that enables local residents to raise funds, sell bonds, etc., to fund investigation and mitigation activities.

Copies of the resulting report, maps, and related information are available for immediate downloading in the formats as indicated below.

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