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DocuSign Envelope ID: 2D970A62 -10C1- 4949 - 9224- E9F2ADB7D568 <br />1. LiDAR and Multi- Spectral Imagery <br />Analysis of LiDAR data enables the assessment of topographic variation at resolutions <br />finer than what can be displayed on 1:24,000 contour maps. In certain environments, <br />such as fluvial and coastal settings, LiDAR analysis may reveal variation in elevation <br />and /or relic landscape features useful for creating site probability zones within a project <br />area. LiDAR scanning is also useful for documenting certain archaeological features and <br />landscapes in the field, such as rock art installations and historic road beds. <br />Multi - spectral, hyper - spectral, and other high resolution imagery may prove useful in the <br />identification of archaeological sites through the analysis of vegetation and soils. For <br />example, sensors designed to recognize radiation across the electromagnetic spectrum <br />have the potential to measure variation in plant growth rates, which can be affected by <br />subsurface features such as foundations, roadbeds, and middens. As the analysis of high <br />resolution imagery is a developing field, detailed process logs should be maintained to <br />facilitate the replication and evaluation of results. <br />2. On -Site Remote Sensing <br />On -site remote sensing techniques such as metal detecting, ground penetrating radar <br />(GPR), and proton magnetometry may be useful at any stage of archaeological <br />investigation. Metal detecting, for example, can provide information for developing <br />recommendations of National Register eligibility for historic period sites during Phase I <br />surveys by providing information on 1) site dates, through recovery of datable objects <br />(e.g., nail types); 2) artifact diversity, and thereby site function; 3) artifact distribution, and <br />thereby site size and organization; and 4) artifact clustering, which may relate to intact <br />features or other deposits below the plow zone. If these types of information would be <br />helpful in completing the National Register assessment of a historic period site during a <br />Phase I survey, then we recommend metal detecting be conducted. <br />If an area is investigated with on -site remote sensing techniques such as metal detecting, <br />ground penetrating radar (GPR), and /or proton magnetometry, a study grid should first <br />be established. The study grid should be tied into a datum, and the datum should be <br />mapped, preferably with GPS technology. Coverage should be systematic within the study <br />grid. The area(s) covered with any of these remote sensing devices should be documented <br />on the field map. For example, if an entire area was swept with a metal detector, then the <br />coverage would be 100 percent of that area. If an area was instead sampled, then only the <br />portions (or the lanes) that were investigated should be marked on the field map as being <br />examined. <br />Metal detecting study lanes should be no wider than 1.5 meters (5 feet) in order to ensure <br />adequate coverage. The vegetation or leaf litter may need to be removed within study <br />lanes in order to effectively sweep the metal detector across the ground surface. All metal <br />detector `hits' should be flagged, numbered, and mapped. A sample of hits should be <br />examined through excavation. Notes should be maintained on each of the `hits' that are <br />investigated, which should include at a minimum the following information: site number <br />(if applicable), date, project number, what the object was, depth of object, and whether it <br />was retained or discarded. <br />North Carolina Oce of State Archaeology — Archaeological Investigation Standard and Guidelines December 2017) Page 9 <br />