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COLORADO LEGACY LAND $CHWARTZWALDER MINE time period does not fit with historical data and there is no plausible explanation that CLL knows other than this mislabeling and poor nomenclature to explain this variability during this time.Regardless,the few months of variable data in 2017 do not alter the conclusion that the mine pool has been chemically stable for the last four years. E.5.2.3. Chemical Stabilization of the Mine Pool Discussion The concentrations and linear regressions for uranium and molybdenum over the last 3.5 consecutive years are shown on Figure E-8. The uranium concentrations (dissolved and total) have maintained an average of approximately 12 mg/L since March 2018 with a positive slope. The majority of the uranium concentrations are in the 10 to 15 mg/L range with more recent data at approximately 20 mg/L. The molybdenum concentrations(dissolved and total) have maintained an average of approximately 0.6 mg/L since March 2018 with a slight negative slope. These stable average concentrations indicates that the in-situ treatments have been effective in controlling the concentrations of these two metals that are particularly elevated in concentration in this mine pool environment. The January 2020 in-situ treatment did not show the dramatic decreases in dissolved uranium concentrations as during the first two in-situ treatments, which is likely an indication that an environment favorable to U(IV)has been achieved. A figure that combines multiple parameters(dissolved)with the mine pool elevation,in-situ treatment periods, and when the RO reject was injected back into the mine is presented on Figure E-9. Note that RO reject was injected back into the mine on a continuous basis starting in mid-2017 and the two events before that, e.g., 2013 and 2015,were only temporary periods of injection.Also note that the dates for the mine pool elevation correspond to the sampling dates and CLL does not have mine pool elevation data before December 2016. There does not appear to be any correlation between the mine pool elevation and the parameter concentrations shown on Figure E-9.The observations from Figure E-9 follows: • The uranium and molybdenum concentrations are directly affected by the in-situ treatments, e.g., decrease during treatment and generally staying low for several quarters,with a subsequent increase toward baseline conditions. • The arsenic and iron concentrations follow a similar pattern as the uranium and molybdenum concentrations. The arsenic and iron concentrations also increase in the 2017 period of the suspect data and coincide with a time that some of the RO concentrate was returned into the mine pool through the "open hole". The increase in concentrations appears to have occurred during the time where the continuous injection of RO concentrate began and is interpreted to be a result of leaching from broken rock in the open hole. Other than during that period (2016-2017) arsenic and iron concentrations decrease as a result of in situ treatment and have remained in line with concentrations observed after the refilling and pre-dewatering period. Iron is typically insoluble in oxidized and neutral conditions observed when the mine initially filled and transitioned to slightly soluble conditions when the mine became mildly reducing from being filled and sealed and the introduction of in-situ treatments. This should be considered a positive development that is consistent with a lack of increase in sulfate as not iron increasing due to iron sulfide oxidation, but rather from reductive solubility increase. Arsenic concentrations generally follow this same trend—low solubility in oxidized conditions with iron present,and slightly more soluble in mildly reducing conditions.However,a change from 3.6 ppb mean AUGUST2022 26 AMENDMENT