2009-03-17_REPORT - M2008078 (3)

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JOSEPH A. CESARE AND ASSOCIATES, INC., GEOTECHNICAL ENGINEERING CONSULTANTS Pincomb (2003). To determine the average aggregate thickness across each lot the volume of aggregate was divided by the area of the lot. This same method was used to determine the average overburden thickness on the lot. Aggregate thickness contour maps and overburden thickness contour maps for the parcel are presented in Appendix A. The aggregate thickness contour maps are shown with and without setbacks from the boundary of the parcel. The setback distance around the parcel was determined to be two times the average gravel thickness of 45 feet for a set back of 90 feet around the perimeter of the parcel. The mined slope was assumed to be at 1 horizontal to 1 vertical (1:1). Based on our investigation and analysis, it is estimated that the portion of the West Farm property considered in our investigation contains a total indicated mineral resource of 26.4 million short tons of aggregates. When a setback of 90 feet is applied to the perimeter of the parcel the total indicated mineral resource drops to 23.9 million short tons of aggregate. In our calculations of aggregate volume the sloping gravel pit walls were also taken into consideration as a loss of material. Assuming a slope of 1:1 and using the average gravel thickness along the pit walls, it was determined that the loss of material due to sloping pit walls is approximately 450,000 cubic yards or 0.675 million short tons. The total amount of aggregate available for mining, after consideration of the losses from setbacks and sloping pit walls, is 23.2 million short tons of aggregate. The estimated volumes and tonnages of aggregate resource are presented in Table 2. Our aggregate resource estimate does not include loss of material due to mining dilution, or loss of fines during washing and processing. Samples were not tested for aggregate characteristics such as hardness, durability, soundness, chemical reactivity, and specific gravity. However, according to the CGS open-fire report 01-19, Koeing, 2001, deposits in the Arkansas River valley have a history of producing well-sired products for construction aggregate and roadbase materials. TABLE 2 Aggregate Volume and Tonnage g9 ' ick s ? ?? 1G4?11 ss? IIIIQ C Q ?? -_ ? a'e :r. .4 3 .?? Ax?!s° , JY 'n46 "« ?.. ,- .'S:xi br. ',`.. • Parcel1 240 45 12 17.6 26.4 Parcel 1 (Setbacks) 215 45 12 15.9 23.9 Parcel1 215 45 12 15.4 23.2 Setbacks & Slopes) Project No. D07.090 - 06/13/07 5 709OtKt