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Page 1 of 1 <br />From: Bird, David <br />Sent: Thursday, January 31, 2008 4:25 PM <br />To: Means, Russ <br />Cc: Pickford, Kate; Keffelew, Berhan; Sorenson, Allen; Mount, Carl <br />Subject: Comments to Whirlwind PAR response <br />Russ <br />Here are my comments on the Whirlwind PAR response. Memo to come later. <br />1) Pg 3. Applicant states that the hydraulic conductivity of the Salt Wash unit was tested to be 2.5 x <br />10-3 m/day, and that the unit "will transmit water but at a very slow rate." In fact, 2.5 x 10-3 <br />m/day falls in the mid-range of sandstone units (Freeze and Cherry, 1979), which typically are <br />considered good aquifers due to their water production capabilities. Characterizing the transmissive <br />properties of the unit as "very slow" may not be entirely accurate. <br />2) To allow monitoring of the potential increase in mine inflow over time as a result of mine <br />expansion, during those periods when pumping of standing water from the mine is performed, I <br />recommend that Energy Fuels be required to include the quantity of water pumped in their periodic <br />reporting obligations. <br />3) Pg. 6. Applicant states that "drinking water standards do not apply to mine water discharge'." <br />Please provide the rationale for this statement. Is applicant implying that the mine discharge is <br />sufficiently distant from any drinking water intake that the site specific conditions allow this <br />generalization, or is the applicant citing a specific regulation? Additionally, applicant contradicts <br />this assertion by presenting a rationale for why sulfate, for which the only regulatory limit relates to <br />drinking water, will not exceed its regulatory limit of 250 mg/L. <br />4) Pg. 7. Applicant states that the probability of contaminating the strata beneath the waste rock <br />piles and other surface facilities is "virtually nil" because of the low permeability and extensivE: <br />thickness of the intervening mudstones. Vertical permeability values in the range of 10-~ t 10-11 <br />cm/sec are referenced. DRMS acknowledges this, but reminds applicant to be cognizant of th~° <br />potential for fracture flow beneath those facilities, in which case a downgradient monitoring well is <br />clearly justified. <br />5) Pg. 7. In reference to the proposed monitoring well, applicant states "if the lower Brushy Basin <br />sandstones are not present, the boring will be abandoned....." DRMS suggests that the monitoring <br />well be installed even under such conditions, providing ground water is encountered. Even <br />completing the well in the Salt Wash Formation, despite the poor water quality that characterizes <br />the formation, could provide indications of mine-related impacts and allow an early warning to <br />prepare mitigation measures. Furthermore, reference is made to establishing baseline conditions, <br />and so far baseline conditions are limited to data from the mine pool, mine inflows, springs, and <br />historic information. A monitoring well will provide essential baseline data. <br />6) Pg. 8. Applicant refers to established baseline data. DRMS reminds the applicant that <br />establishing baseline conditions is an extremely important step in protecting the operator frorn <br />culpability in the event of future environmental impacts for which the ultimate origin is in quE:stion. <br />7) Pg. 15. Regarding the statement that the bulkhead will be installed below the mine seepag~° to <br />prevent that water from entering the mine. DRMS is not clear on what is to prevent mine seepage <br />from building up in the drift and flowing out of the mine portal. Even if the mine entrance area is <br />backfilled, the backfill material will likely not be impermeable. <br />file://C:\Documents and Settings\GRM\Desktop\0708 docs\112\Whirlwind, M-2007-044\Comme... 2/6/2008 <br />