Appendix IV 



will generally be considered ineligible for the 

 National Register, unless a strong case can be 

 made based on other significant evidence such 

 as associated structural remains or diagnostic 

 artifacts, excellent environmental integrity, or 

 close continuity between adjacent segments. 



There are a number of situations in which the 

 evaluation of significance of a trail segment is not 

 simple and straightforward. Hence, the veracity 

 or accuracy of historic documentation may be 

 subject to question and different aspects of 

 physical or environmental integrity may be in 

 varying states of preservation. For example, well 

 defined ruts might be flanked or crossed by paved 

 roads, two-tracks, or jeep roads; or the area 

 adjacent to a swale might be laden with modern 

 intrusions. In those situations where the eligibility 

 of a trail segment is not clear, a case should be 

 made for or against eligibility by addressing the 

 questions in the following section. We strongly 

 recommend that all three elements (historical 

 significance, environmental integrity, and physical 

 integrity) be present for a trail segment to be 

 considered eligible for the National Register, 

 especially trails having only state and local 

 significance. However, there may be cases when 

 only two of the three elements might exist for 

 eligibility to be recommended (for example, when 

 a documented significant trail segment lacks 

 physical integrity, but still maintains excellent 

 environmental integrity or when a trail segment 

 maintains good physical integrity, but lacks 

 environmental integrity, or possible certain 

 segments of National Historic Trails). 



EVALUATIVE QUESTIONS 

 CONCERNING ELIGIBILITY 



The following section is provided as a guide 

 to the field contractors and BLM District Offices 

 in assessing the eligibility of trail segments when 

 eligibility is not clearly established and cannot be 

 immediately determined. 



Historical Significance and Use 



—Is the trail part of the national Trails System 

 Act of 1968 (i.e., Oregon Trail and Mormon 

 Trails)? 



—Does the trail have national, regional, or local 

 historical significance? 



-How reliable and extensive are the documented 

 sources? What level of effort was expended 

 to reach this conclusion? 



-Has use of the trail been sporadic or ongoing 

 to the present? 



-How much use of the trail can be documented? 

 (The expectation of remains will be related 

 to the amount of use.) 



ENVIRONMENTAL INTEGRITY 



—Is the immediate landscape of the trail repre- 

 sentative of or giving an overall impression 

 of the original setting? Can the historical 

 association be recalled? 



—To what degree have modern intrusions, such 

 as well pads, pipelines, access roads, fence 

 lines, reservoirs, etc., compromised the 

 environmental integrity? Are they dominating 

 or easily overlooked? 



—To what extent have natural erosional processes 

 impacted the environmental setting? 



— If the trail is part of the National Historic Trails 

 System, how does the management plan 

 evaluate the environmental integrity of the 

 segment? 



PHYSICAL INTEGRITY 



—What types of physical evidence are observable 

 (ruts, parallel sets of ruts, swales, vegetation 

 changes, artifacts, associated fire hearths, 

 associated structures and foundations, 

 inscriptions, rust stains on cobbles, etc.)? 

 What is the integrity of these remains? 



—Are other nearby segments of the trail better 

 preserved? 



— Do the aerial photos exhibit any evidence of 

 trail remains? 



—Has the evidence been compromised through 

 blading, ditching, crowning, paving, etc.? If 

 so, to what extent? 



—Does the physical evidence display enough of 

 the original appearance and the efssociated 

 artifacts the proper characteristics to recall 

 the historical association? 



—If a two-track with light use is associated with 

 the trail remains, has it compromised the 

 integrity or is it actually lending itself to 

 preserving the trail? 



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