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Zone 7 Water Agency – Tennis Park Test Well Summary <br />and Production Well Design Recommendations <br /> <br /> <br /> 5 Zone 7 Water Agency <br />December 2025 <br /> <br />Table 5. Zone Sampling Information <br />Sample Zone Sample Depth <br />Zone #1 217 feet bgs <br />Zone #2 290 feet bgs <br />Zone #3 370 feet bgs <br />Zone #4 460 feet bgs <br />Zone #5 550 feet bgs <br />Zone #6 690 feet bgs <br />Zone #7 735 feet bgs <br /> <br />The maximum contaminate level for manganese is 0.050 mg/l. The zonal concentration of manganese <br />ranged from a low of 0.036 mg/l in Zone #2 (290 feet bgs) to high of 0.17 mg/l in Zone #5 (550 feet bgs). <br />Based on a review of water quality from other wells in the area, manganese is not a constituent of concern. <br />The elevated and variable manganese concentrations seen in the well are likely a result of incomplete <br />removal of drilling fluids during the well development process. It is not uncommon to have elevated <br />manganese levels in monitoring wells and small diameter test wells in areas/depths where manganese is <br />not a constituent of concern due to the limitations of development with these types of wells. The <br />composite (all zones contributing) concentration manganese was 0.032 mg/l. <br />2.5. Flow Survey <br />On April 9, 2025, a spinner survey was performed in the well by Pacific Surveys to quantify the <br />groundwater flow contribution from individual screen intervals under pumping (dynamic) conditions. <br />Table 6 summarizes the flow contribution for each screen section in the well. The dynamic spinner survey <br />log is included in Appendix A. <br />Table 6. Zonal Flow Contribution Pumping Conditions <br />Screen Interval (feet bgs) Production (gpm) % of Flow <br />195-240 164 27.6 <br />300-320 161 27.2 <br />380-420 97 16.4 <br />470-520 106 17.9 <br />560-600 19 3.2 <br />700-730 31 5.2 <br />740-760 15 2.6 <br /> <br />The results of the spinner survey show that 89% of the total well yield is derived from screened intervals <br />above 520 feet bgs. The low contribution from the lower three screen sections is not surprising, <br />considering the thickness and the resistivity response on the geophysical log of those zones.