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For Outfall 004 in April, the lab data indicates that we may potentially <br />be out of compliance of our DMR limit for potentially dissolved selenium <br />standard of 4.6 ug /1. The lab data indicates a value of 4.9 ug /l for <br />potentially dissolved selenium. However, the total recoverable selenium <br />value, 4.2 ug /1, is below the DMR limit. We have noticed often that the <br />total recoverable value is less than the potentially dissolved value, <br />which is just the opposite as one would expect as the total recoverable <br />digestion is more aggressive than the potentially dissolved digestion. <br />We suspect that the potentially dissolved method is subject to matrix <br />interferences that the total recoverable method is not. Site SSC6 is the <br />site below the Outfall 004 wetlands that PSCM has requested the CDPHE <br />approve as an alternate point of compliance for selenium in the CDPS <br />Permit (CO- 0048275). Data for that site for the same day in April is 3.2 <br />ug /1 potential dissolved selenium and 2.4 ug /1 total recoverable <br />selenium. This indicates that the wetlands site is in compliance for the <br />selenium limit. <br />For Outfall 004 in May, the lab data indicates that we may potentially <br />be out of compliance of our DMR limit for potentially dissolved selenium <br />standards of 4.6 ug /1. The lab data indicates a value of 6.4 ug /l for <br />potentially dissolved selenium. As mentioned above, Site SSC6 is the <br />site below the Outfall 004 wetlands that PSCM is seeking regulatory <br />approval as an alternate point of compliance for selenium. Data for that <br />site for the same day in May is 3.4 ug /l potential dissolved selenium, <br />3.6 ug /l total recoverable selenium, and 3.2 ug /l dissolved solids <br />selenium. This indicates that the wetlands site is in compliance for the <br />selenium limit. <br />On September 12, 2012, the CDPHE issued Notice of Violation #I0- 120912 -1 <br />to the PSCM for the selenium exceedances that occurred in 2011 and 2012. <br />The PSCM is working with the CDPHE to resolve this issue. Possible <br />remedies to the situation include (but are not limited to); indentifying <br />and isolating the source(s) of selenium, using downstream wetlands as a <br />treatment method, utilizing other treatment methods, and /or developing a <br />site - specific selenium standard for the respective receiving streams. <br />The PSCM has performed an extensive monitoring program this year to help <br />20 <br />