2015-08-03_REVISION - P2009025 (5)

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The BLR description of the one -hole test suggests that the water will be recycled in operation. There has been no discussion as to the extent of water treatment prior to re-injection into the borehole and how much make-up water would be required. This also could have an impact on the geochemistry. Every description of the complete UBHM process prior to the current application includes mention of a requirement for a 22"-24" diameter borehole which would include both the water injection system and the "air-lift" slurry recovery system. BLR's statement that a 12" borehole would be adequate for the requested one -hole pilot test appears to contradict previously published information. A much more complete explanation should be requested. Chemistry and Geochemistry The question of the amount of dissolved oxygen that will be in the water injected through the borehole into the face of the orebody was completely misrepresented by BLR in its responses to DRMS staff. At standard temperature and atmospheric pressure there is normally a small amount of oxygen found in water. BLR is correct that at approximately 8000 feet of altitude at the Hansen site, the oxygen concentration in water would be less than at sea level or even at 5000 feet. In fact, when water would be transported from Canon City as proposed by BLR, some of the dissolved oxygen would be expected to bubble out of solution at the Hansen site due to the reduced barometric pressure as altitude increases. The issue, however, is how much atmospheric oxygen would be dissolved into the water as it is being pressurized on site prior to injection into the borehole. The capacity for water to incorporate oxygen into solution is a function of the pressure at the interface of the water and air. Henry's law is one of the gas laws formulated by William Henry in 1803. It states: "At a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid." An equivalent way of stating the law is that the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid. [https:Hen.wikipedia.org/wiki/Henry's law] Since it has not been disclosed by BLR to what degree the compressor will pressurize the water to be injected (that question should have been asked!), it is not now known how much oxygen could be dissolved into the water. Theoretically, since solubility is proportional, one- hundred times standard atmospheric pressure (1500 psi or 100 Bar) would result in a one -hundred times increase in dissolved oxygen. The actual concentration of DO must be determined empirically. However much oxygen is carried down the borehole —at a significantly higher level than normal -- as the pressure drops as the cavern is being excavated, molecular oxygen will bubble out of solution and be available to chemically react with the freshly created ore fragments. That is a classic description of an oxidizing environment. It is true, as BLR stated in its response to the Deficiency Notice, that the intact underground orebody is a reducing environment, as it has been since the uranium oxide was originally "reduced" and deposited from its oxidized soluble U+6 state to the insoluble U+4 state in prehistoric times. That chemical conversion, from an oxidizing to a reducing environment, can be, and is, reversed when strong oxidizers are present. That is precisely what occurs in In -Situ Leach Solution Mining and is expected to occur to a 2