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Scope of Work Preparation of Plans,Specifications and Estimates Sunol Boulevard/1-680 Improvements Project August 21,2023 2.2.2 Ground Control Surveys As a basis, the ground control surveys for this project will initially utilize selected previous approved monuments from the adjacent Interstate 680 (I-680) Express Lanes Project. Prior to use, a verification survey will be performed to determine the positional accuracy of the aforementioned I-680 project monuments. Following verification, a control survey utilizing Global Navigation Satellite System (GNSS), Total Station Survey System (TSSS), and Differential Levelling methods will be performed to establish supplemental control stations throughout the project footprint. The control survey will also include measurements to recovered ROW monuments to aid in land net development. 2.2.3 MTLS Surveys MTLS Ground Control Point Survey Prior to MTLS data collection, MTLS Ground Control Points (GCP)must be installed and surveyed. As provided by R.E.Y. Engineers (REY), the mobile LiDAR subconsultant, 21 GCP's are required for this project. The GCP survey will consist of two separate surveys: 1) GCP installation and first Conventional Real Time Kinematic (CRTK) observation, and 2) differential level survey and second CRTK observation from a different base station location. MTLS Data Collection and Mapping REY will perform a Type A MTLS field survey and prepare the mapping product in Microstation DGN format using CT mapping standards. A map compilation scale of 1"_ 20' showing one(1) foot contours is anticipated. Due to equipment and accuracy limitations, the MTLS mapping limits will generally be the hard surface extents but may include areas outside of those extents such as shoulders, earthen islands at intersections, driveways, and other similar features where bare ground is visible. 2.2.4 Supplemental and MTLS Ground Control Point Survey Control Reports Supplemental Survey Control Report The raw control data will be reduced, compiled, and analyzed. Measurements from a minimum three (3), preferably four(4) Continuously Operated Reference Stations (CORS)will be incorporated. A minimally-constrained least squares adjustment of all raw survey measurement data will be performed to determine the integrity of the survey measurements. Once analyzed and accepted, a fully-constrained least squares adjustment will be performed. Following acceptance of the fully-constrained adjustment, the Supplemental SCR will be prepared. This SCR will include the GNSS, TSSS, and differential level measurements for determination of precise coordinates and elevations of the supplemental control and recovered benchmarks. The Supplemental SCR is a narrative detailing the purpose of the survey, datums utilized, controlling monumentation, post-processing to include the minimally- and fully-constrained adjustments, and the results and conclusions. The Report also includes final coordinates and elevations, Page I 1 of 42