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Refer to correspondence of 13 January 2014 from AWES, LLC. <br />Plate 4 - Durham Pumping Simulation indicates a current groundwater <br />elevation at MW -4 of 4616 and a current groundwater elevation of 4620 <br />approximately 380 feet south of the southern permit boundary. Plate 5 - <br />Coulson Pumping Simulation indicates a modeled groundwater elevation at <br />MW -4 of 4600 and a modeled groundwater elevation of 4605 approximately <br />380 feet south of the southern permit boundary. This is a drawdown of 15 to <br />16feet, not 7.65 feet, which could impact the groundwater wells located near <br />the permit boundary. <br />Refer to correspondence of 13 January 2014 from AWES, LLC. <br />Additionally, the model does not indicate the historic, pre- Durham <br />dewatering, groundwater elevations and potential effects. Please model the <br />potential effects of the proposed dewatering activity from historic <br />groundwater elevations and reevaluate the results of the model from the <br />Durham to Coulson simulations. <br />Refer to correspondence of 13 January 2014 from AWES, LLC. <br />Please provided and explain the mitigation measures to be implemented for <br />the potential impacts to the surrounding groundwater wells and trigger points <br />which would put mitigation measures into effect. Typically, a trigger point of <br />a 2 feet change from historic ground water levels is acceptable. <br />Refer to correspondence of 13 January 2014 from AWES, LLC. <br />20.The Shadow /Mounding Analysis by AWES, LLC dated June 27, 2013 does not <br />accurately predict the potential shadowing and mounding effect of the <br />proposed clay liner at the Varra- Coulson site. The Applicant must define or <br />predict the shadow and mounding effect expected for the Coulson site not <br />Varra Pits 110 and 112. If the analysis determines a shadow or mounding <br />effect will occur offsite impacting a groundwater user, the Applicant must <br />explain all mitigation measures to be implemented and trigger points which <br />would put mitigation measures into effect. Typically, a trigger point of a 2 <br />feet change from historic ground water levels is acceptable. The mitigation <br />measures must include a scenario for the installation of a French drain to <br />direct groundwater around the clay liner and restore groundwater levels to <br />the historic elevation in area of groundwater mounding. <br />Varra Companies, Inc. Coulson Resource Project OMLR M- 2013 -064 11 <br />Correspondence to Peter Hays 21 January 2014 <br />