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Eugene Planning Commission May 2, 2018 Page 10 2.e. "LiDAR geomorphology and Floral Hill Drive Pavement Deformation" GeoScience presented several figures showing geomorphic maps identifying likely slope movements on and in the vicinity of the proposed PUD. These map were prepared on'the basis of LiDAR "hill- shade" images which are generated from a LiDAR digital elevation model (DEM). This is currently the most advanced technology available for generating topographic maps of larger areas. Aware of the limitations of "remote sensing", GeoScience determined that the presence of these inferred slope movements could probably most reliably be supported by field observations of deformations in anthropogenic features such as roads. GeoScience consciously determined not to use 'residences for this purpose, as the resulting testimony is public record and could have repercussions in the property values of affected existing residences. If the LiDAR interpretation was correct, Floral Hill Drive should have been offset to the east mainly in the areas of the landslide lobes mapped on the LiDAR hillshade. This was indeed found to be the case and was shown on both aerial and site photos using straight lines to emphasize the lateral offset in the pavement at the landslide lobes, which are present correspondingly on both sides of the street. In addition, whereas the pavement is mostly relatively flat (both in portions of the road with overlay and in the portions with just the original pavement), significant vertical deformation ("wrinkling") of the pavement is present at the junction of two of these landslide lobes. In their rebuttal on March 28, 2018, Branch Engineering attempts to disprove the conclusion that the lateral and vertical deformation of the pavement of Floral Hill Drive is due to active slope movement. Instead they propose that the lateral shifts are due to "mailbox locations and driveways"". This is incorrect. At the location of the northern of the two mail boxes in this section, the actual pavement is a couple of feet west of the area with the maximum eastward pavement deflection, which is located about 120' north of the mailbox. Similarly, the southern of the two mailboxes is located approximately 30' north of the area of maximum deflection of the southern of the two lobes crossed by the road. In addition, as mentioned above, in these areas, the pavement does not change appreciably, and the eastward shift is notable along both the eastern and western edge of the pavement. Nonetheless, although the Branch rebuttal document contains only statements and three photographs which are not annotated to prove their point, the HO finds that: "the applicant's engineerprovides a detailed factual analysis to support its conclusion that there is no indication of landslide movement in that area. " In other words, the annotated air photos and site photos presented by GeoScience as evidence are 19 Branch Engineering GeoScience Inc Addendum Rebuttal 3/28/18, p. 1, para. 2 & 3.