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Mr. Mark Campbell September 27, 2004 Page 3 SITE GROUNDWATER ~~ CIVIL RES7JU RCES, LLC Civil Resouroes has installed and surveyed seven piezometers as part of our geotechnical investigation in June, 2004 at the locations shown on Figure 2. The limited data indicates a slight hydraulic gradient toward the South Platte River to the northwest The average depth to groundwater in June and July, 2004 was approximately 25 feet. The piezometers will be monitored monthly in order to determine the seasonal fluctuations of the groundwater surface. STRUCTURES W1TN 200 FEET OF DISTURBED AREAS The known, permanent, man-made structures within 200 feet of the proposed mine area are listed below: • Highway 85 (western boundary}, • WCR 27 (eastern boundary), • WCR 8, south of the Villano Property 8 North of Sasaki 8 Adams Property, • WCR 6, south of the Yokooji Property, Fulton Ditch Lateral along the east boundary, • Gas Wells (Villano 8 Adams Properties), • Underground gas utilities, • Overhead power utilities. EXISTING EASEMENTS It is our understanding that the following easements exist at the site: • A proposed 60-foot ROW parallels the eastern Section 19 line for future road widening for WCR 27, • A proposed 50-foot ROW parallels the northern Section 19 line for future road widening for WCR 8, • A proposed 50-foot ROW parallels the southern Section 19 line for future road widening for WCR 6, • An existing ROW for Highway 85 extends along the entire western property boundary, • A 15-foot telecommunication easement extends along the eastern boundary of Villano, • The existing oil well on Villano has a 50-foot gasline easement running due north of the well, • The existing oil welt on Adams has a and a 50-foot easement along Highway 85, and • The Yokooji property has a 50-foot Panhandle Eastern Pipe Line Company easement along the northwest property line, and a 75-foot Public Service easement from the power lines on the northern margin. We assumed that the Fulton Ditch Lateral would maintain a prescriptive access easement of 35 feet from the ditch centerline or 15 feet from top of bank, whichever is greater. STABILITYANALYSES The stability of the proposed mining limits was evaluated at five sections under anticipated and required loading conditions around the perimeter of the site, discussed below. The computer program XSTABL was used for the analysis. The method for selecting the critical failure surface for each analyzed loading condition is the following. Modified Bishop's method of analysis is used to find the cdtical failure surface by randomly searching with 20 termination points and 20 initiation points (400 failure circles) over a broad range of the slope surface. This procedure is repeated over different initiation and termination locations until the most critical factor of safety failure surface is identified. The range is narrowed for the final mn of 400 circles to determine the lowest factor of safety. The final stability run analyzes the critical surface using the Spencer method by inputting the X and Y coordinates of the circle center and the X; location