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NORWEST <br />C O R P O R A T I O N <br />Page 2 <br />January 30, 2015 <br />Letter to Mr. Marshall <br />The first reason is the nature of the lithology. The six shallow <br />( <225 feet deep) holes are to be drilled through the Mahogany <br />Zone of the Parachute Creek Member of the Green River <br />Formation, which is the most prolific oil shale unit in the Uinta <br />Basin. Oil shale by its very nature is an impermeable rock unit, <br />and can only act as an aquifer if it is extensively fractured. <br />The second reason is the isolated ridges. Even if the oil shale is <br />found to be extensively fractured, there is limited capacity for a <br />particular ridge to hold groundwater as it is separated from <br />other ridges in the area by the deep drainages. Therefore, not <br />only is there a limited volume of material in which <br />groundwater could be contained, but hydraulic connectivity of <br />the beds is at a minimum because the ridges are isolated from <br />one another. The only groundwater flow (if present) within a <br />particular aquifer would be north- south, following the trend of <br />the ridges, otherwise it would rapidly drain out of the ridge and <br />into the drainage below. <br />The third reason is the dip of the strata. The strata dip to the <br />west, and groundwater flow in low permeability formations <br />largely follows the dip. Since the ridges run north -south and <br />groundwater flow (if present) would be to the west, it means <br />that practically all groundwater contained within an individual <br />ridge would have drained out of the ridge and into an adjacent <br />drainage. This would also preclude the possibility of <br />substantial quantities of groundwater being developed and <br />maintained at a particular location. <br />Taking all of these factors into consideration, it is believed to be <br />highly unlikely that any groundwater will be encountered in the six <br />shallow holes. However, the one deep hole (GRH -1, 1800 -1900 <br />feet deep), being nearly 8.5X deeper than the other holes, is <br />anticipated to encounter groundwater in the sandstone units <br />contained within the Douglas Creek Member of the Green River <br />Formation, located approximately 400+ feet below the base of the <br />Mahogany Zone (likely around 600 -650 feet below the surface at <br />our drill hole locations). It was in anticipation of encountering this <br />groundwater that the containment pit for the GRH -1 pad was <br />planned to have much larger dimensions than for the shallower <br />holes. <br />Due to the unlikelihood of encountering groundwater in the six <br />shallow holes, TOTAL is committed to the plugging and <br />