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repaired by a conventional base repair construction method. In addition, this project also overlaid the existing roadway surface with asphalt concrete within the project limits. In 2015, O'Grady Paving, Inc. completed emergency repair work under the Annual Streets Resurfacing and Preventative Maintenance Project, CIP No. 145003, for $76,120 in areas adjacent to the 2013 repairs. The work included 21 locations along West Las Positas Boulevard between the DMV and Stoneridge Drive. Over 20,000 square feet of existing depressed pavement was milled and leveled with 1/2-inch hot mix asphalt concrete and 1,200 square feet of distressed pavement was also repaired. The repairs near the DMV appear to be relatively stable. In 2018, Ranger Pipelines completed leveling and roadway repairs at the Tassajara Creek crossing as part of the recycled water pipeline installation and traffic lane restoration work. This work included leveling work on and immediately adjacent to the segments repaired in 2013 and 2015. In summer 2019, cracks and minor settlement began showing up within repaired areas, including areas filled with the lightweight cellular concrete. By spring 2020, significant settlement had occurred in the street. The Streets Maintenance Division then installed signage and began work on temporary leveling and roadway repairs. Ultimately, the repairs became greater than the division's capacity to efficiently handle. In fall 2020, Goodfellow Bros., Inc. completed the pavement repair and roadway leveling on West Las Positas Boulevard between Hacienda Drive and Stoneridge Drive for $261,041 . The improvements restored the roadway to a safer operating condition but did not restore the roadway to the original grade. The pavement repair areas were within previously repaired roadway sections. DISCUSSION The City has attempted to mitigate the pavement settlement and distresses on West Las Positas Boulevard regularly with preventative maintenance, rehabilitation, and pilot repair projects. The roadway continues to experience differential settlement within repaired areas and will require the reconstruction of portions of the roadway. BSK Associates, under an on-call contract with the City, performed a preliminary geotechnical study over summer 2021 that included a review of historical records, previous studies and borings. A detailed visual inspection and visual monitoring were performed. The preliminary study identified that the pavement settlement and distress could be caused by several different issues ranging from trench failures, tree impacts, and settlement. The study made a recommendation for a subsurface geotechnical investigation, to collect the necessary data and information to recommend possible mitigation options/approaches so that the continued, persistent settlement and subsequent extensive repairs to the roadway would be significantly reduced. The scope of work for the proposed geotechnical study includes subsurface investigation, laboratory testing, engineering analysis, and recommendations. The first phase of work entails 35 hollow-stem auger borings to depths of approximately 7 to 40 feet below ground to collect samples. The testing on the samples will gather data/info related to the depth of fill within the roadway, moisture content, soil type, expansion potential, resistance value, the perceptible relationship between the moisture content Page 3 of 5