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Docu5lgn Envelope ID: FC3F95A4.9A61-4664-B416.344D1AA47C5B <br />Remote Sensing (ASP RS) accuracy standards for large scale class I maps for V = 100' (and l" = 200' for <br />some areas) mapping in order to be incorporated into existing participants' GiS systems. <br />DEFINITIONS <br />The following definitions shall apply throughout this SOW: <br />1. &iij(insReuresentation <br />The term "Building Representation" shall mean Planimetric Feature representing the representation of <br />an erect building (not under construction or ruin) that serves a primary business, government, or <br />residential function. <br />SCOPE OF WORK <br />Utilization of stereo imagery to generate building representations with height attribution. This method will <br />allow for data extraction without radial displacement and delineation of features obstructed by building <br />lean. <br />1. Horizontal accuracy shall be consistent with Second Order, Class 1, i.e. ninety- five percent <br />(95%) confidence interval of 2 em base error and 20 parts per million linear errors. <br />2. Data creation shall be constrained to American Society for Photogrammetry and Remote Sensing <br />(ASPRS) accuracy standards for large scale class I maps for V = 100'. <br />3. Vertical datum shall be NAVD88. All vertical stations set will be tied directly to NGS <br />monuments whose orthometric height was determined by differential leveling and adjusted <br />by the NGS on, or after June 1995. <br />4. Units shall be U.S. Survey Feet. <br />S. All features will conform to the representative State Plane Coordinate System required <br />by the customer. <br />6. Each enclosed building representation polygon shall contain two "z" (elevation) attributes <br />representing the highest point on the building (building height above ground and mean sea <br />level), excluding flagpoles, chimneys, and other features smaller than 4 square feet. <br />7. Original building IDs shall be maintained with new building IN generated for buildings. A <br />separate data set for demolished/removed building representations will also be created. <br />TESTED CHARACTERISTIC <br />MEASURE OF ACCEPTABILITY <br />Feature <br />Features captured will represent building representations for <br />permanent structures that meet the minimum size requirements. <br />This excludes RV parks. <br />Feature Types <br />Primary buffifln -Polygon enclosing all erect buildings <br />(not under construction or ruin) that serve primarybusiness <br />and residential functions (i.e, houses, apartments, commercial <br />facilities). Includesattached covered porches, permanent <br />overhangs, carport roofs, covered sidewalks, etc. as part of <br />the building. Do not show common rooflines (e.g, between <br />town homes, or interior sections/firewalls in commercial <br />buildings). <br />Courtyard or Atrium - Polygon created inside a primary building <br />that is fully encompassing of an open area. <br />Fecondarry hnildinn- Polygon enclosingall erect buildings <br />(not under construction or ruin) that serve as secondary or <br />minor buildings (garage/outbuilding). Includes the following: <br />Smokestack - A closed circle enclosing the base of a large <br />cylindrical smokestack. <br />Silo/Bin - Polygon enclosing a large cylindrical receptacle for <br />farm product storage. <br />Tank - Polygon enclosing commercial storage tank features <br />(Oil, chemical and propane). Do not capture small private/ <br />residential propane tanks. <br />i <br />Water tower - Polygon encfosin$ water tower. <br />______ <br />SCAG_Extemal Entity Fomr._C:11074408_June 17,2020 8 ort0 <br />