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The City of Provo, Utah, began construction for a new wastewater treatment facility in 2020. The plant was originally built in 1956, with the last major upgrade occurring in 1978. The existing plant lacks the ability to remove phosphorus and nitrogen from wastewater, which contributes to algae blooms in Utah Lake. The project completely upgrades the facility with advanced state-of-the-art Membrane Bioreactor technology. The new facility will exceed current state and federal regulations and is anticipated to meet future needs to reduce the amount of nutrients that enter the lake. The City of Provo celebrated the opening of the new treatment plant in June 2025. The regional geology of the project site is dominated by Lake Bonneville deposits, which include near-normally consolidated, fine-grained soils. The area is also located within the Intermountain Seismic Belt, one of the most seismically active areas in the interior western United States. The Wasatch fault zone is approximately 1–1/2 mi east of the project site, with additional younger, less-active faults located within 20 mi in the vicinity. Sands and some silts are prone to liquefaction at the project design earthquake magnitude 7.09 and peak ground acceleration of 0.70g. For the new facility to perform satisfactorily, a ground improvement system was deemed necessary to limit static settlement, improve bearing capacity, and mitigate potential liquefaction-induced settlement. The project team designed a ground improvement system consisting of 3-ft diameter Vibro Replacement Stone Columns (VRSC) extending 34 ft through the project’s soft silt and clays with a 25% replacement ratio. The design and construction included 20 pre- and 20 post-improvement CPTS side-by-side to evaluate the vibro densification effects. Construction also included temporary shoring and dewatering to install the ground improvement system below grade near the water table. This paper will discuss (1) the site exploration and characterization, (2) how the vibro stone column treatment selected based on the site unique soil profile, (3) how to verify the effectiveness of the vibro stone column treatment under the design earthquake, (4) how the surrounding soils as measured by post-improvement CPTs, and soil strength increased over time due to pore pressure dissipation, and (5) lessons learned from the construction of stone columns through the challenging geology consisting of saturated soft clays and Lake Bonneville gravels and cobbles.