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f. The final reclamation of any phase of excavation shall be completed within two years of the commencement of the final reclamation process. Excavation shall be limited so that at any point of time a maximum of one phase is being reclaimed while one phase is being excavated. (Development Title Section 9-1415.2{o}) A. Initial excavation shall begin in Phase 2 away from arty sensitive structures such as canals, pipelines,and roadways to allow possible detection of any weak soil strata and/or perched zones of saturation. When the initial excavation has reached full depth, large !, block samples shall be obtained by a geotechnical engineer to determine the actual strength properties and analyze any possible change in the computed factors of safety. Additionally, for every 25 feet of excavation depth in each phase, an inspection by a geotechnical engineer shall be performed that evaluates whether the excavation has penetrated soil conditions other than those that were anticipated in the slope stability analysis. The inspection report shall determine if soil conditions exist that would decrease the anticipated factor of safety and include recommendations for revisions to the slopes in the affected area The geotechnical engineer for the above inspections shall be selected by San .Joaquin County with the applicant being responsible for the cost of the professionalized services plus an administrative fee of 15 percent h. Install three monitoring wells to a depth of ten feet below the invert elevation of the California Aqueduct. The wells shall be located between Phase 2 sedimentation ponds and the California Aqueduct for monitoring of any shallow perched groundwater. The applicant shall monitor water levels quarterly to ensure that if a zone of saturation forms beneath the aqueduct, it does not rise to a level higher than the invert of the aqueduct. The quarterly monitoring reports shall be sent annually to Development Services Division. Such monitoring wells are not required if sedimentation ponds are maintained below the invert elevation of the Aqueduct i. All phases of the mining operation shall be dry pits. The maximum depth of mining shall be six feet above the high level of the water table, but in no case shall the excavation be more than 150 feet below original grade. As a basis for initial and ongoing mining depths, the applicant shall submit annually to Development Services Division quarterly reports monitoring the water depths for a minimum of ten water supply wells around the general perimeter of the permitted mining area In the event that the applicant is unable to obtain or retain at least ten existing water wells for water level measurements, the applicant shall procure new wells for monitoring purposes at locations acceptable to Development Services Division. The applicant shall provide a verifiable bench mark at each well site that can be referenced for compliance monitoring. Based upon the water depth monitoring reports, Development Services Division may recalculate the high Ievel elevation of the water table, thereby adjusting the maximum allowed depth of mining. Under no circumstances shall the maximum allowed depth of mining be increased. Based upon current and recent historic groundwater level data,the groundwater elevation beneath the site is approximately 87 feet above mean sea level. Based on that elevation, the minimum mining elevation shall not be below 93 feet mean sea level in all phases. w Conditions of Approval - 5 - CSX-91-5