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<br />addition, tailings impoundments elsewhere in the state, notably <br />Henderson, have similar designs. As the design appears to be <br />common in the industry, I suggest there are many others in the <br />state. Earthquake frequency notwithstanding, if Washington's DSS <br />knows something about this design that we do not, it seems prudent <br />to verify their skepticism about this method. <br />I understand from conversations with Bruce Humphries that the <br />Colorado Geological Survey examined the design of the San Luis <br />tailings impoundment during the permit review period and found no <br />fault with the design. However, we now have one state agency at <br />odds over a similar design. I note that the DSS's objections are <br />empirical, not rigorously calculated, but am concerned with the <br />DSS's note that tailings de-watering is critical to the stability <br />of the dam; to my knowledge, BMG conducts no tests to affirm the <br />moisture content of the tailings prior to applying each lift. <br />Bruce has suggested that Pendleton and/or Sorenson re-examine the <br />permit correspondence with the CGS regarding the impoundment <br />design. I would recommend further that we ask BMG about the DSS's <br />comments and determine whether BMG is testing the tailings for <br />moisture content. <br />cc: Jim Stevens <br />Carl Mount <br />m:min\CRNJWL.mem <br />