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II. Distillation Process Concerns We have not yet been provided access to any chemical analysis of the process solution recovered from mining activities. We believe an opportunity to analyze the process solution highly significant for the evaluation of American Soda's plan to meet its duties as an operator with respect to water quality and quantity. We have two related yet independent concerns in this regazd. First, the process and temperature utilized by American Soda is likely to cause an accumulation of oil, or related organics, in the production cavity over time. We understand that American Soda's process may not result in instantaneous distillation of oil shale [Cummins and Robinson, "Thermal Degradation of Green River Kerogen at 150 Degrees Celsius to 350 Degrees Celsius": 1972 USBM, Report of Investigation 7620]. However, instantaneous distillation is not the only issue; distillation is generally temperature and time dependent, and may occur over time at temperatures lower than those required for instantaneous distillation. In the event that this latter type of distillation of oil shale occurs, it will dramatically alter the assessment of aquifer and cavity integrity with respect to water quality, and the way in which the cavern reclamation should be considered. An assessment of this latter type of distillation could conceivably be made requiring American Soda to depressurize its pilot cavity in order to obtain a sample of the liquid surface of the production solution. We distinguish between the liquid surface and the process solution for essentially the same reason as one would look for oil at the top of a vessel containing both oil and water. We have not seen any evidence of such a request, or of any other efforts to fully evaluate the potential for oil shale distillation over time. Our second concern is that there appears to be no attention to the potential for American Soda's process to take dawsonite along with nacholite. Dawsonite is a mineral found in the lease azea which could be subject to solution mining using essentially the same process that American Soda proposes to use. However, as we set forth in some detail below, American Soda's lease stipulations prevent recovery of this resource. At a minimum, the DMG should be testing for dawsonite and chemicals related to dawsonite (especially aluminum / alumina chemistry's) since this mineral is a protected resource and indication that destructive distillation of oil shale is in progress. FURTHER DETAIL RELATED TO COMMENT ABOVE LITERATURE SEARCH The following is an excerpt from the article "Soluble-Salt Processes for In-Situ Recovery of Hydrocarbons From Oil Shale", Journal Of Petroleum Technology September 1977, pg.1079 "In addition to halite and narholite, dawsonite [NaAI(OI-n2C0~] is also present in the target region in average concentrations of about 5 percent. Dawsonite is not very soluble in water. I[ decomposes when heated, giving off C02, aad reacts in an aqueous environment with silica (SiO~ to give various insoluble alumina silicates, the most common of which is enalcite (NaA1SiZ0~."