Both the National Historic Preservation Act and the Archaeological Resources Protection Act mandate that Federal agencies only disclose site locations if no harm, theft, or destruction of cultural resources will result from disclosure. The pertinent sections of the acts are as follows:
- The head of any Federal agency, after consultation with the Secretary, shall withhold from disclosure to the public, information relating to the location or character of historic resources whenever the head of the agency or the Secretary determines that the disclosure of such information may create a substantial risk of harm, theft, or destruction to such resources or to the area or place where such resources are located. Section 304, National Historic Preservation Act of 1966, as amended.
- Information concerning the nature and location of any archaeological resource for which the excavation or removal requires a permit or other permission under this Act or under any other provision of Federal law may not be made available to the public under subchapter II of chapter 5 of title 5 of the United States Code or under any other provision of law unless the Federal land manager concerned determined that such disclosure would--(1) further the purposes of this Act or the Act of June 17, 1960 (16 USC 469-469c), and (2) not create a risk of harm to such resources or to the site at which such resources are located. Section 9, Archaeological Resources Protection Act of 1979.
To comply with these mandates, the park superintendent has established three classes of cultural resource sites based on their ability to withstand visitor impacts due to the nature of the sites themselves, active physical protection, indirect protective mechanisms, and visitor demands to access the sites. Park employees may only provide location information only to Class I and II sites.
Locations of Class I sites are readily disclosed to the public. Class I sites have a long history of visitation, are marked on USGS topographic maps, are described in widely available guide books, are generally known to visitors, and/or are actively promoted as destinations. Since Class I sites receive the greatest impacts from visitors, they receive the greatest physical protection and management.
Class II site locations may only be disclosed to the public when visitors request the information by site name, photograph or description, and the requested site is on the official Class II sites list. Class II sites may be as well known to visitors as Class I sites, but they are either more fragile or vulnerable to visitor impacts than Class I sites or there are other concerns (such as the presence of endangered species or visitor safety hazards) which result in Class II sites being unable to withstand the number of visitors received by Class I sites.
Class III sites are considered vulnerable, fragile cultural resources. Class III site locations are withheld from the public to ensure site preservation and protection, as mandated in the National Historic Preservation Act (NHPA) and Archaeological Resources Protection Act (ARPA). While visitors are not told where Class III sites are located, they are welcome to discover them on their own.
In summary, the intention of this policy is to balance demands of visitors to access cultural sites with mandates to preserve and protect significant cultural resources. To balance access with preservation, the site disclosure policy is directly linked to programs of direct and indirect site protection. A list of Class I and II sites will be maintained at all park visitor information stations and within appropriate divisions.