Submitted By: Jimmy Lopez
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Presentation By: Sean Lanier
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Department: Engineering
FORMAL TITLE:
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Change Order and additional expenditures under the contract with All Webbs Enterprises, Inc., for the construction of two Upper Floridan Aquifer Wells at Water Treatment Plant No. 2 in the amount of $176,736
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OCALA'S RELEVANT STRATEGIC GOALS:
Operational Excellence
PROOF OF PUBLICATION:
N/A
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BACKGROUND:
On April 1, 2025, City Council approved the award of the contract to All Webbs Enterprises, Inc. (AWE) for the construction of two 24-inch diameter Upper Floridan Aquifer Wells. Well No. 11 and No. 12 will be located at the future Water Treatment Plant No. 2 (WTP#2) site for redundancy in water availability throughout the City of Ocala (City). WTP#2 is located at 3744 South Pine Avenue.
FINDINGS AND CONCLUSIONS:
AWE has commenced drilling at the City's WTP#2 site, focusing on Well Nos. 11 and 12. Initial efforts on Well No. 11 employed mud rotary methods, but circulation was lost at 70 feet below land surface (bls). To regain circulation, AWE implemented alternate drilling techniques; however, the results were inconsistent. During drilling a sinkhole was identified approximately 20 feet from the rig which prompted a geotechnical review. The geotechnical evaluation of both well sites showed no anomalies within the top 25 feet of lithology. Consequently, AWE proposed drilling Well No. 12 with a smaller 12.25-inch bit to better evaluate the local geology.
At 70 feet bls, circulation was again lost, but drilling continued to 83 feet bls to collect borehole data. Based on drilling, testing, and previous design assessments, it has been identified that an unknown 13-foot open void exists at both sites between 70 and 83 feet bls. AWE is seeking the City's approval to install a 30-inch diameter casing down to approximately 90 feet bls, intended to isolate the zone responsible for circulation loss and sinkhole formation. This ch...
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