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On September 12, 2012 the CDPHE issued Notice of Violation #I0-120912-1 to the PSCM for <br />selenium excursions of the selenium effluent limits in PSCM's CDPS discharge permit (CO - <br />0048275) in 2011 and 2012 that occurred at Outfalls 002 and 004. PSCM is working with the <br />CDPHE to resolve this issue. Long Term measures proposed to the CDPHE to remedy the <br />situation include (but are not limited to): developing seasonal effluent limits for selenium during <br />renewal of the CDPS Permit; and using downstream wetlands as a treatment method. PSCM <br />performed an extensive synoptic water quality sampling study and aquatic life surveys in 2013 at <br />existing and temporary surface water monitoring sites along Grassy Creek, Cow Camp Creek and <br />tributaries associated with both drainages. The sampling and surveys were conducted over three <br />seasons during 2013 to help identify the sources and fate of selenium. Data collected and <br />findings related to these efforts were submitted to the Colorado Water Quality Control Division <br />in late February 2014. Upon issuance of the new CDPS Permit many of the parameter standards <br />fell under a temporary modification set to "Current Conditions" to allow PSCM time to resolve <br />uncertainty as to whether the Table Value Standards were appropriate and necessary to protect <br />the aquatic life. PSCM has initiated a sampling plan to perform comparative analysis of <br />biomonitoring and water quality data to determine appropriate standards. <br />The CDPS and CDRMS sample data from PSCM from 2011 through 2014 support a finding that <br />the mine is not causing exceedances of the in -stream standards. Using dissolved selenium data <br />collected at SSG2 on Grassy Creek and at SSF13 on Fish Creek over five years (2010-2014), the <br />85`' percentile was calculated to determine whether each receiving stream has been in attainment <br />of the previous selenium numeric limit of 4.6 ug/1 for chronic aquatic life. This statistic is <br />founded in the CDPHE 303d listing criteria for impaired surface waters. The 85`h percentiles for <br />D selenium were 0.55 ug/1 and 2.68 ug/1 for Fish Creek and Grassy Creek, respectively. Based <br />on these calculations, the receiving streams (Fish Creek at Site SSF13 and Grassy Creek at Site <br />SSG2) are in attainment of the selenium standard (85th percentile of data for the last five years). <br />C) Permit Requirements of the Colorado Discharge Permit System (CDPS) <br />PSCM currently maintains three outfalls effected by the areas being requested for this Phase III <br />bond release: Ponds 002 (NPDES2) Spoil Spring 1(SSSPGI / NPDES6), and Spoil Spring 2 <br />(SSSPG2/ NPDES5) which are monitored under the CPDS Permit No. CO -0048275. Prior to <br />the CDPS permit renewal, effective January 1, 2016, NPDES5 and NPDES6 feed pond 004 <br />32 <br />