(1) If no heritage property exists within project's area of potential impact, the department may proceed with the project. If, during the course of the project, historic or prehistoric properties are identified, the department shall notify the SHPO immediately, provide it with site information, and stop any project work that could harm the property until the SHPO assesses the site's value as a heritage property. The SHPO shall provide its assessment to the department within two working days after receipt of a request for comments. If the site is judged to be a heritage property, the department will follow the procedures identified in subsection (2) of this rule.

(2) If heritage properties exist within the project's area of potential impact, the department shall determine, in writing, whether the project will alter or affect the attributes of the site which contribute to its heritage value and whether such alteration will be substantial. If the department determines that a project will substantially alter attributes of value to heritage properties, it shall prepare a written explanation of why one or more of the actions has been chosen and how it will be carried out:

(a) abandon the proposed project;

(b) modify or redesign the proposed project to avoid or lessen harmful impacts;

(c) mitigate harm or alteration through any method including recordation, excavation, other further documentation; or

(d) undertake the project with no avoidance or mitigation measures.

(3) Upon completion of its assessment of project impact and selection of the proposed action, the department will forward its determination to the SHPO for review and comment.

(4) The SHPO will review and comment on the department's assessment of project impacts and proposed actions within ten working days of receipt of a request for comment.

(5) If, the SHPO does not concur with the department's assessment and proposal the department and the SHPO will, attempt to resolve the difference. If the department and SHPO cannot agree on the SHPO recommendation the department shall decide how to proceed and shall document its decision in writing for the project file. The department shall provide the SHPO with a copy of its final decision.