Class III Survey Exclusion Policy

Class III Survey Exclusion Policy

Class III Survey Exclusion Policy

Wyoming State Historic Preservation Office
2301 Central Avenue
Barrett Building, Third Floor
Cheyenne, Wyoming 82002
Phone: 307-777-7697


Printable Policy:


Section 106 of the National Historic Preservation Act (106) indicates that Federal Agencies need to take into account the effect of Federal undertakings on historic properties. A Federal "undertaking" is defined in the National Historic Preservation Act of 1966, as amended, Section 301(7) as; 

"Undertaking" means any project, activity, or program funded in whole or in part under the direct or indirect jurisdiction of a Federal agency, including-- 


A. those carried out by or on behalf of the agency; 

B. those carried out with Federal financial assistance; 

C. those requiring a Federal permit, license, or approval; and

D. those subject to State or local regulation administered pursuant to a delegation or approval by a Federal agency. 


As part of the identification effort required under the Advisory Council's Regulations 36 CFR 800.4(a), it is the policy of the Wyoming SHPO to require a Class III 100% intensive inventory of all Areas of Potential Effect (APE) for projects except in the instances listed below. 


  • The project is not an undertaking as defined in the National Historic Protection Act of 1966, as amended. 
  • The project is an undertaking, but is exempt from Class III Survey because:
    • The project's APE has been inventoried previously by a documented Class III survey of sufficient quality to meet current SHPO and Secretary of Interiors Standards. (Note that surveys conducted prior to 1980 generally do not meet current SHPO and Secretary of Interior Standards) 
    • Previous Class III surveys in the vicinity indicate a low probability for any historic or prehistoric sites to exist in the area of effect. These previous surveys must meet current standards and be of sufficient size, and similar in topography, geology, geomorphology, hydrology and environmental setting to provide a statistically valid predictive model. 
    • The APE has been previously disturbed to such an extent that the probability of intact cultural resources remaining in the area is remote. (Note that agricultural plowing does not constitute sufficient previous disturbance nor does the existence of an existing Right-of-Way or Easement.) 
    • The project consists entirely of replacing or repairing existing facilities within existing disturbed areas and the facilities themselves are not historic resources. 
    • Activities which involve no more than 2 square meters of cumulative surface disturbance and no more than 1 square meter of contiguous disturbance in any given location, unless within the boundaries of a known historic property or an unevaluated cultural resource. 
    • Other special situations may be excluded from Class III survey on a case-by-case basis. 


The above situations exempt a project from a Class III survey, but not from compliance with Section 106 and 36 CFR Part 800. 

For all undertakings, a Class I inventory (file and literature search) must be conducted by the agency or a qualified cultural resource consultant in order to meet the requirements of 36 CFR Part 800.4(A)(1). If known historic properties are located in the file search, additional field work in the form of site relocation, National Register of Historic Places evaluation, determination of effects and development and implementation of mitigation plans may be necessary to meet the requirements of Section 106. 

If the Federal Agency determines that the undertaking does not require a Class III Survey, the Federal Agency shall initiate consultation with SHPO by furnishing SHPO with the appropriate documentation. This documentation will include, but is not limited to, the following: 

  • Project name, description and legal location. 
  • Narrative description of results of Class I files/literature search. 
  • Justification for exclusion from Class III survey. 
  • USGS Topo map illustrating project location, previous survey area, previously recorded sites, previous disturbance, appropriate photos if needed, etc.

Wyoming State Historic Preservation Office Menu


About UsAbout Us

Events & TrainingEvents & Training


Online ToolsOnline Tools


Wyoming State Historic Preservation Office

The Wyoming State Historic Preservation Office documents, preserves, and promotes Wyoming’s heritage with our preservation partners.


Get a Compliance Letter...

Help with Funding...

Get a Poster or purchase Archaeology wear...

How do I list a property on the NRHP?...

How do I find forms?...

Contact Us...


What's New

Visit Us On Facebook