"Adverse impact on visibility" means visibility impairment which interferes with the management, protection, preservation, or enjoyment of the visitor's visual experience of a Class I area. This determination shall be made on a case-by-case basis taking into account the geographic extent, intensity, duration, frequency and time of visibility impairments, and how those factors correlate with (a) times of visitor use of the Class I area, and (b) the frequency and timing of natural conditions that reduce visibility. This term shall include effects on integral vistas designated in Chapter 114.
06- 096 C.M.R. ch. 100, § 4