Common use of Survey Control Clause in Contracts

Survey Control. Simultaneous to the LiDAR data collection mission, QSI will conduct a static (1 Hz recording frequency) survey of the horizontal and vertical positions of two or more survey control dual-frequency DGPS base stations established at monuments with known coordinates. Maximum baseline lengths between control points and the aircraft GPS do not exceed 24 kilometers (13 nautical miles). After the static GPS data have been collected, the files will be processed using the Online Positioning User Service (OPUS). Multiple sessions will be processed over the same monument to confirm antenna height measurements and reported OPUS position accuracy. Control monument locations will be certified by a QSI Washington PLS. Q uality control real-time kinematic (RTK) ground check survey data will be collected within the project area, with an established Root Mean Square Error (RMSE) of less than 2 cm. Absolute laser spot accuracies will be statistically analyzed based upon an adequate sample (500 per 50,000 acres, depending on access and GPS conditions within study area) of well-distributed RTK ground survey points on open, bare earth surfaces with level slope. Deliverables Deliverables will match standard for Puget Sound LiDAR Consortium: Report of Survey Text report that describes survey methods; results; vendor's accuracy assessments, including internal consistency and absolute accuracy; and metadata .pdf, .doc, or .odt format Aircraft trajectories (SBET files) Aircraft position (easting, northing, elevation) and attitude (heading, pitch, roll) and GPS time recorded at regular intervals of 1 second or less. May include additional attributes. ASCII text format All-return point cloud List of all valid returns. For each return: GPS week, GPS second, easting, northing, elevation, intensity, return#, return classification. May include additional attributes. No duplicate entries. ASCII text and LAS version 1.2 format 1/100th USGS 7.5-minute quadrangle (0.75 minute by 0.75 minute) tiles Ground point list List of X,Y,Z coordinates of all identified ground points. ASCII text. 1/100th USGS 7.5-minute quadrangle (0.75 minute by 0. 75 minute) tiles Ground surface model Raster of ground surface, interpolated via triangulated irregular network from identified ground points. No unavoidable point misclassification ESRI floating point grid, 3 ft cell size, snapped to (0,0), 1/4th USGS 7.5-minute quadrangle (3.75 minute by 3.75 minute) tiles First-return (highest-hit) surface model Raster of first-return surface, cell heights are highest recorded value within that cell, voids may be filled with ground surface model ESRI floating point grid, 3 ft cell size, snapped to (0,0), 1/4th USGS 7.5-minute quadrangle (3.75 minute by 3.75 minute) tiles Intensity image GeoTIFF,1.5. ft pixel size, 1/4th USGS 7.5-minute quadrangle (3.75 minute by 3.75 minute) tiles Projection Washington State Plane North Horizontal Datum NAD83 (CORS96) Vertical Datum NAVD88 (GEOID03) Units U.S. Survey Feet Delineations USGS Quadrangle tiling scheme Area of Interest – King County, WA T he area of interest (AOI) for this cost proposal includes 700,329 acres spread through King County, WA (Figure 1). Previous LiDAR collections for the PSLC and Pierce County are shown in grey. Overlap between collections will facilitate data matching. The AOI will be buffered by 100 meters to ensure complete coverage and adequate point densities around study area boundaries.

Survey Control. Simultaneous to the LiDAR data collection mission, QSI will conduct a static (1 Hz recording frequency) survey of the horizontal and vertical positions of two or more survey control dual-frequency DGPS base stations established at monuments with known coordinates. Maximum baseline lengths between control points and the aircraft GPS do not exceed 24 kilometers (13 nautical miles). After the static GPS data have been collected, the files will be processed using the Online Positioning User Service (OPUS). Multiple sessions will be processed over the same monument to confirm antenna height measurements and reported OPUS position accuracy. Control monument locations will be certified by a QSI Washington PLS. Q uality Quality control real-time kinematic (RTK) ground check survey data will be collected within the project area, with an established Root Mean Square Error (RMSE) of less than 2 cm. Absolute laser spot accuracies will be statistically analyzed based upon an adequate sample (500 per 50,000 acres, depending on access and GPS conditions within study area) of well-distributed RTK ground survey points on open, bare earth surfaces with level slope. Deliverables Deliverables will match standard for Puget Sound LiDAR Consortium: Report of Survey Text report that describes survey methods; results; vendor's accuracy assessments, including internal consistency and absolute accuracy; and metadata .pdf, .doc, or .odt format Aircraft trajectories (SBET files) Aircraft position (easting, northing, elevation) and attitude (heading, pitch, roll) and GPS time recorded at regular intervals of 1 second or less. May include additional attributes. ASCII text format All-return point cloud List of all valid returns. For each return: GPS week, GPS second, easting, northing, elevation, intensity, return#, return classification. May include additional attributes. No duplicate entries. ASCII text and LAS version 1.2 format 1/100th USGS 7.5-minute quadrangle (0.75 minute by 0.75 minute) tiles Ground point list List of X,Y,Z coordinates of all identified ground points. ASCII text. 1/100th USGS 7.5-minute quadrangle (0.75 minute by 0. 75 minute) tiles Ground surface model Raster of ground surface, interpolated via triangulated irregular network from identified ground points. No unavoidable point misclassification ESRI floating point grid, 3 ft cell size, snapped to (0,0), 1/4th USGS 7.5-minute quadrangle (3.75 minute by 3.75 minute) tiles First-return (highest-hit) surface model Raster of first-return surface, cell heights are highest recorded value within that cell, voids may be filled with ground surface model ESRI floating point grid, 3 ft cell size, snapped to (0,0), 1/4th USGS 7.5-minute quadrangle (3.75 minute by 3.75 minute) tiles Intensity image GeoTIFF,1.5. ft pixel size, 1/4th USGS 7.5-minute quadrangle (3.75 minute by 3.75 minute) tiles Projection Washington State Plane North Horizontal Datum NAD83 (CORS96) Vertical Datum NAVD88 (GEOID03) Units U.S. Survey Feet Delineations USGS Quadrangle tiling scheme Area of Interest – King County, WA T he area of interest (AOI) for this cost proposal includes 700,329 acres spread through King County, WA (Figure 1). Previous LiDAR collections for the PSLC and Pierce County are shown in grey. Overlap between collections will facilitate data matching. The AOI will be buffered by 100 meters to ensure complete coverage and adequate point densities around study area boundaries.scheme