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Mr. Travis Marshall <br />Mr. David Bird <br />Division of Reclamation, Mining, & Safety <br />• May 11, 2011 <br />Page 8 <br />sampling that falls within the normal distribution about the mean of <br />the reported values should be expected to be within the natural <br />range of variability of the groundwater thus justifying the 2 <br />standard deviation rationale. <br />7. Section 62.2 pg 30: What is the temperature of the hot water delivered versus the <br />ambient ground water temperature? <br />Ambient groundwater temperature at a depth of approximately 2000 ft is <br />approximately 95° to 105° F. Injected water temperature is intended <br />to be approximately 350° F at surface, falling to approximately 300° F <br />average in the reservoir. <br />8. Section 62.2 pg 30: States that solutions produced during the nahcolite leaching will be <br />routed to an oil/gas/water separator to sequester ambient gases. Are there any liquid <br />hydrocarbons anticipated to be produced? What means are proposed to separate or <br />sequester these, and what are the means of disposal? <br />Ambient gases already present in the formation include small but <br />persistent concentrations of C02 and methane. These gases will be <br />routed to a flare. Liquid hydrocarbons are not expected to be present <br />in liquids produced during leaching as the leaching fluid is below <br />pyrolysis temperatures. However, in the Parachute Creek Member small <br />bits of bitumen (possibly detrital) have been detected, and if <br />present, may melt during leaching to form a skin of liquid <br />hydrocarbons in the separator as long as the separator fluid remains <br />hot. If a liquid hydrocarbon skin or layer forms during the leaching <br />phase, it will be collected in the oil water separator and combined <br />with subsequent oil production from pyrolysis phase of the project. <br />9. Section 62.4 pg 31: Regarding the statement that the voids generated will be filled with <br />water. Please describe the source of the refill water. <br />Based on discussion with the BLM, Shell is maintaining the option to fill <br />or not to fill the reservoir with water, which is consistent with the <br />option to rely on water-assisted cooling or natural cooling. If water is <br />used to re-fill the voids generated by leaching and pyrolysis, the source <br />of water will be from a Shell water right. <br />10. Section 6. 5.2 pg 40: Regarding the footnote on page 40, has a contingency plan been <br />devised in the event that 300°F as a leaching temperature does not conserve the oil shale <br />resource? <br />Shell laboratory testing and field experience indicates that liquid <br />hydrocarbons would not form at the planned leaching temperature and <br />project timeframe, even though over geologic time, such hydrocarbon <br />production might be possible. The Oil Shale resource would be conserved <br />• in this fashion, not wasted. Contingency plans as indicated in the