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The quantity of sand and gravel was estimated for each of the fields labeled on the attached map. The average thickness of overburden and deposit was fast determined from the vazious drill holes representing each field. The net recoverable tons pec mineable acre for each field was then calculated, using a ten percent waste factor for strioning andpro~~sing. A preliminary mine map was prepazed for the property (not included with this report), considering typical mining set-backs from pipelines, roads and structures. The house at the southeast corner ofField-3 (0.8acres) was assumed to remain. This allowed an estimate of the mineable acres for each field, compazed to the gross acreages listed. These acreages were estimated by scaling distances from an aerial map, for lands outside the various road right-of--ways, and should be considered only as accurate as the methods stated. These values are cnmmari~Pd in the table below: Field 1 Field 2 Field 3 Field 4 Field 5 Total Avera e Overburden D th 5.4 6.5 7.3 7.3 10.8 - _ Aver e Sand&Gravel De th 39.6 36.1 36.0 38.3 36.2 - Product Tons/Mineable Acre 92K 84K 84K 89K 84K 86.8K Gross Acrea e 58.9 48.3 X3.3 40.9 38.2 239.6 Mineable Acr a 48.3 43.6 38.5 35.2 32.2 197.8 Recoverable Tons/Field 4.4M 3.bM 3.2M 3.1M 2.7M 17.OM In conclusion, this property should be expected to yield approximately seventeen million tons ofconstruction grade aggregates. No bulk samples were obtained for laboratory testing for aggregate quality, however the Saint Vrain Creek deposit has a history of producing acceptable quality products. While the primary scope of this project was to estimate the sand & gravel on the property, some issues concerning the future lining methods were encountered that should be discussed briefly. The strata beneath the sand and gravel deposit were generally a stiff, sandy clay, overlying a clayey, weathered sandstone bedrock. While not encountered on all holes at the depths of drilling, the underlying materials may need to be further evaluated to determine suitability for use as a compacted clay liner, should that method of lining the mined azeas be chosen. This sandstone bedrock would not be as impermeable as the Pierre shale often utilized as lining materials. Similarly, while the overburden had some plasticity at some drill locations, I was field classifying it as a silty, sand. No samples were taken, but these materials should be tested in the future before assuming compatibility as a clay liner material. Should the on-site materials not be suitable for a compacted clay liner, a slurry wall might be required for this site. If you have any questions, please feel free to contact me. Stan Peters, P.E. Enclosures :Drilling Logs and a Drill Hole Location Map Page 2