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Notice of National Natural Landmark Designation for Irvine Ranch, Orange County, CA

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National Park Service, Interior.


Public notice of National Natural Landmark Designation.


The Secretary of the Interior has determined that an area of 36,398 acres within the Irvine Ranch in Orange County, California meets the criteria for national significance and has designated this site a National Natural Landmark.

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Steve Gibbons at 360-856-5700, extension 306.

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On October 6, 2006, Interior Secretary Dirk Kempthorne designated a 36,398-acre area within Irvine Ranch in Orange County, California, as a National Natural Landmark. This area is significant for its Mediterranean shrublands, including extensive areas of chaparral and coastal sage scrub associations. It is one of the largest areas of this association remaining in the South Pacific Border Province. The Irvine Ranch NNL also represents a remarkably unique, long time-range stratigraphic succession that shows the linkage between tectonic framework, provenances, sedimentology, paleoenvironments, paleontology, paleoclimate, landscape evolution and geologic history. In this regard it represents one of the most critical time intervals and locations in the geologic history of the South Pacific Border Province.

The Secretary of the Interior established the National Natural Landmarks Program in 1962 under the authority of the Historic Sites Act of 1935 (16 U.S.C. 461 et seq.). The National Park Service (NPS) manages this program using regulations found at 36 CFR Part 62. Potential natural landmarks are identified in studies by the NPS and from other sources, evaluated by expert natural scientists, and, if determined nationally significant, designated as landmarks by the Secretary of the Interior. When designated, a landmark is included in the National Registry of Natural Landmarks, which currently lists 581 National Natural Landmarks nationwide. Of the 581 listed landmarks, half are administered solely by public agencies, i.e., Federal, State, county or municipal governments. Nearly one-third are owned solely by private parties. The remaining natural landmarks are owned or administered by a mixture of public and private owners. Owner permission must be obtained to visit natural landmarks that are privately owned or not managed for public access. Designation does not infer a right of public access.

National natural landmark designation is not a land withdrawal, does not change the ownership of an area and does not dictate activity. However, Federal agencies should consider impacts to the unique properties of these nationally significant areas in carrying out their responsibilities under the National Environmental Policy Act (42 U.S.C. 4321 et seq.). Designation could result in State or local planning or land use implications. National Natural Landmark preservation is made possible by the long-term, voluntary commitments of public and private owners to protect the outstanding values of the areas. Information on the National Natural Landmarks Program can be found on the Internet at​nnl.

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Dated: December 7, 2006.

Margaret A. Brooks,

National Natural Landmarks Program Manager.

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[FR Doc. 06-9692 Filed 12-13-06; 8:45 am]