initiate a preconstruction meeting with each utility owner. A vacuum truck was utilized to excavate and safely remove material around the pipe and install a trench box and/or steel plating. Once the trench box or plate protection was installed, a smaller excavator would pretrench around the utility crossing prior to constructing the full-depth SCCB cutoff wall. The contractor maintained the slurry level temporarily below the utility and had a full-time, dedicated spotter until the cutoff wall panel crossed the utility at a full depth. SCCB backfill was then pumped to the top of the trench to fully encase the utility. Excavating Under Bridge The contractor initiated and executed a value engineering proposal to install the cutoff wall below the Rio Linda Boulevard Bridge to avoid performing temporary traffic control, excavating around numerous live utilities and turning off a streetlight that the City of Sacramento wanted kept in service. The bridge deck had approximately 15 ft to 17 ft (4.6 m to 5.2 m) of clearance above the existing ground surface elevations, and the cutoff wall work pad leading to the bridge was sloped with approximately 10 ft (3.05 m) of grade change, thereby greatly increasing the complexity of the proposed modified cutoff wall alignment. Forgen used GPS grading models to build a stepped panel approach to the grade changes. The model helped to ensure panel tie-ins/cutoff wall continuity was achieved, as well as to maintain the top elevation of the cutoff wall within the prism of the levee embankment. A total of four stepped panels on each side of the bridge were required to construct the cutoff wall over the full 10 ft (3.05 m) of the work pad grade changes. To avoid excavation conflicts with the 15 ft to 17 ft (4.6 m to 5.2 m) of bridge deck clearance, the contractor used a small excavator to pretrench before installing the full depth cutoff wall. Multiple spotters were used to avoid a conflict between the excavator and the bridge as well as to ensure a safe excavation around a fiber optic utility crossing. The contractor safely executed both Rio Linda Boulevard Bridge crossings underneath the bridge deck with zero utility or bridge conflicts. SCCB construction below Rio Linda Blvd. bridge Forgen's batch plant DEEP FOUNDATIONS * NOV/DEC 2020 * 83