(i) Review existing information on historic properties potentially affected by the undertaking, including any data concerning the likelihood that undentified historic properties exist in the area of potential effects;

(ii) Request the views of the State Historic Preservation Officer on further actions to identify historic properties that may be affected; and

(iii) Seek information in acordance with agency planning processes from local governments, Indian tribes, public and private organizations, and other parties likely to have knowledge of or concerns with historic properties in the area.

(2) Based on this assessment, the Agency Official should determine any need for further actions, such as field surveys and predictive modeling, to identify historic properties.

(b) Locating historic properties. In consultation with the State Historic Preservation Officer, the Agency Official shall make a reasonable and good faith effort to identify historic properties that may be affected by the undertaking and gather sufficient information to evaluate the eligibility of these properties for the National Register. Efforts to identify historic properties should follow the Secretary's ``Standards and Guidelines for Archeology and Historic Preservation'' (48 FR 44716) and agency programs to meet the requirements of section 110(a)(2) of the Act.

(c) Evaluating historical significance. (1) In consultation with the State Historic Preservation Officer and following the Secretary's Standards and Guidelines for Evaluation, the Agency Official shall apply the National Register Criteria to properties that may be affected by the undertaking and that have not been previously evaluated for National Register eligibility. The passage of time or changing perceptions of significance may justify reevaluation of properties that were previously determined to be eligible or ineligible.

(2) If the Agency Official and the State Historic Preservation Officer agree that a property is eligible under the criteria, the property shall be considered eligible for the National Register for section 106 purposes.

(3) If the Agency Official and the State Historic Preservation Officer agree that the criteria are not met, the property shall be considered not eligible for the National Register for section 106 purposes.

(4) If the Agency Official and the State Historic Preservation Officer do not agree, or if the Council or the Secretary so request, the Agency Official shall obtain a determination from the Secretary of the Interior pursuant to the applicable National Park Service regulations.

(5) If the State Historic Preservation Officer does not provide views, then the State Historic Preservation Officer is presumed to agree with the Agency Official's determination for the purpose of this subsection.

(d) When no historic properties are found. If the Agency Official determines in accordance with Section 800.4 paragraphs (a) through (c) that there are no historic properties that may be affected by the undertaking, the Agency Official shall provide documentation of this finding to the State Historic Preservation Officer. The Agency Official should notify interested persons and parties known to be interested in the undertaking and its possible effects on historic properties and make the documentation available to the public. In these circumstances, the Agency Official is not required to take further steps in the section 106 process.