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Page 2 December 19,2018 <br /> With the exception of well MW-TPZ, the wells were all completed in the Salt Wash Member of the <br /> —- Morrison Fortnatiom MW-TPZ was completed on May 7, 2013 Aepth of 20 feet below ground <br /> surface (bgs) at the toe of the main waste rock pile at the Topaz Mine. This well was installed to <br /> monitor for the possible occurrence of leachate impacts from the waste rock pile;no groundwater was <br /> encountered. Well MW-Sunl was completed on December 5,2012 to a depth of 1,240 feet;MW-Sun2 <br /> was completed on December 18, 2012 to a depth of 735 feet; and MW-Sun3 was completed on May <br /> 10,2013 to depth of 571.5 feet. <br /> The locations of the constructed wells are shown in Figure 1. Monitoring well diagrams are presented <br /> in Figures 2 through 5.Well permits are shown in Attachment A. <br /> Sampling Methods <br /> Table 1 summarizes the sampling events of the three monitoring wells located downgradient of the <br /> mine complex.The table demonstrates that at least six quarters of sampling data were collected at each <br /> well. Note that samples Sunday 1 and Sunday 65 (a duplicate) collected at the MW-Sunl well on <br /> December 10,2012 were collected by the use of a Bennett Sample Pump(Bennett).The Bennett pump <br /> uses a stainless steel piston driven by pressurized nitrogen that cycles groundwater to the surface.These <br /> samples were collected after several days of purging the MW-Sun 1 well. <br /> Beginning in 2013, low-flow BESSTTM samplers were installed in wells MW-Sunl and MW-Sun2. <br /> The low-flow sampling method was selected because of the extremely low recharge rate of the <br /> constructed wells. This method was proposed to DRMS and BLM, and was accepted. The BESSTTM <br /> samplers function by displacement of water in a downhole chamber through the use of nitrogen <br /> injection. WWL installed the BESSTTM sampling pumps and operated the sampling equipment during <br /> all sampling events.EFR personnel were on site to collect,label and ship the samples to the analytical <br /> laboratory. EFR used various sample identifications through the five quarter program. WWL, by <br /> convention,used actual well name for the last sampling event. <br /> Typically,low-flow sampling is conducted with a minimal(less than a few tenths of a foot)drawdown <br /> in the well.Low-flow methods do not typically involve well purging prior to sampling. Because of the <br /> low recharge rate and extensive amount of time involved to collect samples from the MW-Sunl and <br /> MW-Sun2 monitoring wells, Energy Fuels proposed a sampling method that reflected the initial <br /> method used at MW-Sunl. This method involved the initial evacuation of the BESSTTM tubing water <br /> above the well screen followed by low-flow sampling of the well water within the screened interval. <br /> This method was accepted by both the BLM and DRMS (see letter of June 10, 2013 and emails of <br /> December 3 and 10,2013).At well MW-Sun3,the Bennett pump was used for all sampling events. <br /> The samples collected on September 24,2013 at well MW-Sunl used low-flow methods with the <br /> newly installed BESSTTM well apparatus.Because of the extremely low recharge rate at the wells,the <br /> low-flow sampling method initially used at MW-SunI involved some experimental samples. Sample <br /> SMW 1 Pre involved sampling of the BESSTTM tubing water in the well above the pump intake,and <br /> did not involve any purging of water in the screened interval.A duplicate sample,SMW 11,was also <br /> collected.Sample SMW 1 Final involved sampling of water within the well screen,but again,no well <br /> purging was conducted. Samples SMW 1 Pre2,SMW 1 Final 2,and SMW 11(2)(Dup)represents re- <br /> analysis by the analytical laboratory(GEL Laboratories LLQ to correct for the dilution factor for anion <br /> analyses.The sampling event information is presented in Table 1. <br /> Mest 121918.doc <br />