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Cripple Creek & Victor Gold Mine <br />Valley Leach Facility Expansions <br />Detailed Design for Permitting <br />NewFields Project No. 475.0106.064 <br />September 2025 <br /> <br /> <br /> <br />Page 6 <br />3.3. Valley Leach Facility Expansion Geophysical Survey (IGES, 2023) <br />Intermountain GeoEnvironmental Services (IGES) completed a seismic velocity survey within the <br />VLF1 and VLF2 Expansion footprints. The survey included ten seismic velocity P-wave (VP) <br />refraction profiles and three seismic velocity shear wave surveys (VS100), to determine the seismic <br />velocity profile of the shallow subsurface to a depth of 0 to 40 feet and to delineate depth to <br />bedrock. The (VS100) was completed to determine the shear wave velocity profile of the near <br />surface to determine the seismic site class. Ten survey lines between 150 feet and 870 feet were <br />evaluated in the facility's footprint and along the general alignments of the internal <br />embankments. <br />The results of the geophysics indicate the site wide VS100 (average shear wave velocity in the <br />upper 100 feet of the subsurface) ranges from approximately 1,700 to 2,800 feet per second <br />(fps). Approximate depth to bedrock is delineated in the profiles by displaying two general <br />velocity zones. Low density materials exhibiting velocities (VP) of less than 4,000 feet per second, <br />and higher density materials exhibiting velocities (VP) of greater than 4,000 feet per second. <br />Based on these findings approximated depth to bedrock ranges from 0 to 60 feet depth along all <br />profiles. Section B displays the shallowest area of bedrock ranging from 0 to 10 feet depth along <br />the profile and Section I displays the deepest bedrock ranging in depth from 50 to 60 feet. The <br />IGES report is provided in Appendix A. <br />3.4. Laboratory Testing Program <br />Laboratory testing in support of the VLF Expansions included index testing of foundation soils. <br />Samples from the test pit program were labelled and tested at NewFields on-site materials <br />testing laboratory. The purpose of the testing program was to characterize the materials <br />encountered during the field investigation, confirm the field interpretation of the materials, and <br />to develop engineering parameters to aid in the VLF Expansions’ design. <br />Materials testing on representative samples obtained during the field investigation included the <br />following laboratory tests: <br /> Natural Moisture (ASTM D2216) <br /> Sieve Analysis with No. 200 Sieve Wash (ASTM D6913) <br /> Atterberg Limits (ASTM D4318) <br />Individual laboratory sheets are included in Appendix B, and a summary of the laboratory testing <br />is included in Table B.1 in Appendix B.