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2024 ANNUAL GROUNDWATER MONITORING REPORT TEICHERT AGGREGATES AND GRANITE CONSTRUCTION VERNALIS AREA level data,collected semi-annually from 1960 through 2020 by the California Department of Water Resources, are also available for one shallow zone well. Groundwater levels in the shallow wells have declined an average of approximately 25 feet to the lowest levels since the period of record began in 1994. Groundwater elevation contour maps indicate relatively steady shallow groundwater flow in easterly to southeasterly directions over the period of record. Groundwater levels observed in the deep wells are typically lower than in the shallow zone and exhibit greater seasonal and annual fluctuation than groundwater levels in the shallow wells due to increased aquifer confinement and pumping stresses. In the early 2000's,groundwater levels in the deep zone noticeably declined, likely in response to reported increased pumping stress and overall dry conditions. In the mid 2000's,substantial recovery of groundwater levels occurred, however,seasonally high-water levels remained below those observed in the mid to late 1990s. Since 2013,groundwater levels in the deep wells have approximately declined an average of about 100 feet. The groundwater quality record documents stable conditions in both the shallow and deep aquifer zones.Shallow groundwater is generally of Ca-Na/HCO3-CI or Na-Ca/HCO3-CI type and deep groundwater is of Ca-Na/HCO3-SO4 or Ca-Na/SO4-HCO3 type. The overall content of soluble minerals is slightly higher in shallow zone groundwater than in deep zone groundwater. Elevated nitrate concentrations in groundwater, documented since pre-mining times to the present, are most likely attributable to historical and ongoing agricultural land use in the area. In summary,the existing data record shows no indication that mining operations have changed groundwater quality to date. LUHDORFF&SCALMANINI CONSULTING ENGINEERS 10