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Page 5 <br />Requirement Regulation Comment <br />modification (expired December 31, 2018) of the <br />Selenium standard as “current conditions”. <br /> <br />PSCM claims that part of the high Selenium levels is <br />due to water received from Scotchman’s Gulch, <br />which is in contact with the Lewis Shale which <br />contribute to high Selenium values in many of the <br />streams in the area. <br /> <br />According to the AHR, the detection limit for <br />Ammonia is .05 mg/l and that all values above the <br />detection limit are compared to the table standard on <br />page 87 of the EPA website: <br />http://nepis.epa.gov/Adobe/PDF/20003O3L.pdf <br />Based on this table it does not appear the ammonia <br />limit was exceeded given the temperature of the <br />water and the pH at the time of sampling. <br /> <br />Mercury exceedances: <br />According to page 22 of the 2016 AHR, the Colorado <br />Department of Public Health and Environment <br />performed a reasonable potential analysis on PSCM’s <br />outfalls and determined that there was no reasonable <br />potential for PSCM’s outfalls to exceed the Mercury <br />limit; therefore, Mercury monitoring is no longer <br />required for PSCM’s outfalls. <br /> <br />10. Interim Narrative <br />Standard for Ground Water <br /> <br />CWQCC regulation 41 <br /> <br />It was determined that bedrock groundwater points of <br />compliance are unwarranted at the PSCM mine. <br /> <br />Well SGAL70 serves as the PSCM Grassy Creek <br />Alluvial groundwater point of compliance. This <br />wells was approved to be the groundwater point of <br />compliance well for the original Seneca II mine (see <br />TR-47 and Attachment 7-3 of the C-1980-005 permit <br />for details). <br /> <br />Table 7 of the AHR provides the Ground Water Point <br />of Compliance Standards for the SGAL70 Alluvial <br />Well. <br /> <br />Upon review of the 2016 data for SGAL70, one of <br />the standards from Table 7 were exceeded. <br /> SGAL70, selenium in May 2016 <br />