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107 <br /> Hands Four Development Cooperative <br /> SW Orange County, IVC <br /> Page 2 <br /> Diabase rocks are not unusual in the region. Diabase is a dark, iron-rich, fine-grained <br /> crystalline igneous intrusive rock that was injected as magma through local fractures and <br /> fissures in the surrounding rocks. The closest mapped diabase dike to this site is located about <br /> 1,000 feet southeast of the site along the Collins Creek stream valley (NCGS 1978; 2016) <br /> (Figure 2), Diabase dikes, if present, can provide a significant source of water for water-supply <br /> wells due to the enhanced fracturing that occurs with the emplacement of diabase. No diabase <br /> has been mapped on the property in previous work by the NCGS. <br /> Geophysical Evaluation <br /> Geo-Solutions Limited, Inc. (Geo-Solutions) conducted a magnetometer survey of the property <br /> on June 7, 2023. A map prepared by Geo-Solutions is presented in Figure 3. The <br /> magnetometer survey measures the deviations of the earth's total magnetic field as magnetic <br /> energy passes through the rocks near the surface. Iron-rich rocks, like diabase, can produce <br /> measurable deviations in the natural magnetic field, and magnetometer surveys can identify the <br /> presence of diabase, as well as other changes in rock type, including abrupt contacts between <br /> different rock types. <br /> Geo-Solutions identified two areas of higher total magnetic field readings (colored in red) in the <br /> southeastern corner of the property (Figure 3). The location of these dikes corresponds to <br /> north-south trending ridges that are present in the topography at the site. The presence of <br /> high magnetic readings and their narrow, long linear nature indicate the likely occurrence of <br /> diabase dikes in the subsurface. In GMA's opinion, the apparent diabase dike locations <br /> represent favorable drilling targets for future water-supply wells. <br /> Field Investigations <br /> GMA personnel conducted a reconnaissance of the site on June 8, 2023. The purpose of the <br /> visit was to identify important geologic conditions on the property that could influence the <br /> availability of groundwater. Field reconnaissance included a physical walk-over of the property <br /> to evaluate rock exposures and stream valleys/ridges as indicators of the composition and <br /> physical structure of the underlying rocks. The locations of rock exposures with planar features <br /> (e.g., fractures, faults,joints, and bedding planes) were documented using a GPS device, and <br /> the orientations of planar features were measured using a geologic transit/compass. GMA's <br /> field effort was conducted in conjunction with preliminary data collected from the geophysical <br /> survey conducted by Geo-Solutions on June 7, 2023. <br /> GMA personnel traversed the property generally along cleared pathways and along stream <br /> beds. We observed several outcrops of metavolcanic rocks along the stream bed of Collins <br /> Creek located east of the property. We also observed an outcrop of metasedimentary rock near <br />