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MEMORANDUM A& Adrian Brown 8. Piezometers have been installed outside the diatreme, in Grassy Valley, Poverty Gulch, Squaw Gulch, Arequa Gulch,and Vindicator Gulch (Plate 12). In general these piezometers read water levels near ground surface. Notable exceptions are the piezometers on the east wall of the Wild Horse Extension Mine(WHEX),and SGMW-05, the westernmost piezometer in Squaw Gulch.These wells are dry to the depth drilled,typically greater than 250 feet.These wells demonstrate localized drawdown in the Precambrian rockmass adjacent to the steep-sided portions of the diatreme, caused by drainage through the low permeability granitic rocks into the diatreme due to the approximately 3,500 feet of head drawdown caused by the flow from the drainage tunnels.This data has been used to estimate the capture boundary of the drainage tunnels in the diatreme (currently the Carlton Tunnel),which is shown as a red dashed line on Plate 12. Note that the capture area excludes the double hatched infiltration area where infiltration is captured by Grassy Valley(see above).The Carlton Tunnel capture boundary encloses an area of approximately 8.6 square miles. Conclusion This comprehensive memorandum has been prepared to provide a detailed determination of the static water level within the diatreme prior to and following surface mining. It contains all relevant shaft and borehole data, all information related to mineral samples, and a full exposition of their analysis and interpretation. The conclusions of the memorandum are: 1. In the pre-mining(natural) state, infiltration of precipitation passed in general across the diatreme to the west, emerging in large part into Squaw Gulch. However, seepage flowed to the east from the Grassy Valley capture zone (double hatched area). 2. Since the installation of drainage tunnels, infiltration of precipitation has been largely captured by those tunnels, most recently the Carlton Tunnel.Approximately 0.81 square miles of the eastern fringe of the diatreme (which includes the Grassy Valley capture zone [double hatched area]) has not been affected by the drainage tunnels. References ABC, 2015.Amendment 11 Hydrogeochemistry Evaluation. Report prepared by Adrian Brown Consultants, Inc., for Cripple Creek and Victor Gold Mining Company in support of Amendment No. 11, Office of Mined Land Reclamation Permit M-80-244. Dated December 15, 2015 Eary LE, Runnells DD, Esposito KJ, 2003. Geochemical controls on ground water composition at the Cripple Creek Mining District, Cripple Creek, Colorado.Applied Geochemistry 18(2003) 1-24 Hamm JC, 1972. Cripple Creek Hydrology—Cameron Mine. Memorandum from J.C. Hamm to D.B.Smith, Golden Cycle Corporation, dated August 8, 1972. (Copy in Attachment 1). Henderson CW, 1926. Mining in Colorado—A History of Discovery, Development, and Production. U.S. Geol. Prof. Paper 188, pp. 57-59, 1926. Page 9 Adrian Brown Consultants, Inc. 130 W.4rh Ave., Denver CO 80223 303-698-9080 www.abch2o.com