Evaluation of Groundwater Supply Alternatives Within Bernal Subbasin

Zone 7 Water Agency – Hansen Park Test Well Summary and Production Well Design Recommendations 2 Zone 7 Water Agency December 2025 built figure (Figure 3). Multiple coarse-grained intervals were identified in the borehole that could be targeted in a future production well between 298 feet and 756 feet bgs. Coarse-grained intervals above 298 feet bgs were not considered potential target zones in a new well due to potential for poor water quality. LSCE submitted a test well profile (Figure 3) to Zone 7 for approval. The test well design included multiple intermediate bentonite seals to isolate each coarse-grained zone and a cement annular seal to a depth of 265 feet bgs. Test well design features are included in Table 1. Table 1. Hansen Park Test Well Construction Information Depth of Borehole (ft bgs) 770 Borehole Diameter Diameter (in.) 30-Inch (0-100 ft bgs) 14.75-Inch (100-770 ft bgs) Depth of Well (ft bgs) 766 Conductor Casing Depth (ft bgs) 0-100 Diameter (in) 18 I.D.* Wall Thickness (in) 0.3125 Material Type Mild Steel Blank Casing Depth (ft bgs) 0-298, 318-458, 578-608, 628- 656, 676-736, 756-766 Diameter (in) 8.625 O.D.** Wall Thickness (in) 0.250 Material Type Mild Steel Screened Interval Depth (ft bgs) 298-318, 458-578, 608-628, 656-676, 736-756 Screen Type Louvered (Ful-Flo) Slot Size (inches) 0.060 Screen Material Type Mild Steel Gravel Envelope Depth (ft bgs) 267-325, 440-585, 600-640, 650-690, 720-770 (type/size)SRI #8 Transition Seal Depth (ft bgs) 265-267 Seal Material Type Fine Sand Intermediate Seal Depth (ft bgs) 325-440, 585-600, 640-650, 690-720 Seal Material Type Bentonite Chips Annular Seal Depth (ft bgs) 0-265 Seal Material Type 10.3 Sack Sand/Cement Grout *Inside Diameter **Outside Diameter