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Based on a review of the water quality data, no sites exceeded the sulfide standard of 0.002 mg /1, the <br />aquatic life ammonia standard detection limit of 0.05 mg /1, nor either the drinking water standard (2 <br />ug /1) nor the aquatic life standard (0.01 ug /1) for mercury. Based on the NPDES permit renewal, the <br />CDPHE performed a reasonable potential analysis on NPDES2 and NPDES4 and determined that <br />there was no reasonable potential for the outfall to exceed the mercury limit; as such, mercury <br />monitoring is no longer required at these outfalls. <br />The Peabody Sage Creek Mine includes six monitored spoil springs ( SSPG1 through 4 and 6 and <br />6A0). Spoil Springs SSSPG 1 and 2 flow into Pond 004 (NPDES4) and Springs SSSPG 3, 4, 6, and <br />6A flow into Pond 002 (NPDES2. Due to the fact that the post- mining land use for the Peabody Sage <br />Creek Mine has been approved as grazing and wildlife habitat, a review of the water quality data was <br />compared to the CWQCC surface water agricultural standards. Three of the surface water <br />agricultural use standards were exceeded for the past three years. The manganese standard was <br />exceeded at SSSPG2 and SSSPG6. However, as indicated in CWQCC Regulation 31, the standard of <br />0.2 mg /1 applies to plants grown in acidic ( <6.0 pH) soils. In alkaline soils, as found in the Peabody <br />Sage Creek Mine Permit area, a more appropriate standard is 10 mg /1. The 10 mg /1 standard was <br />exceeded once at SSSPG6 in 2011 with a value of 13.1 mg /1. The manganese standard at SSSPG6A, <br />located downstream of SSSPG6, collected the same day was 0.031 mg /1. <br />For NPDES4 and NPDES2, the 13 samples of the selenium noted were NPDES permit limit <br />exceedances. The CDPHE issued a Notice of Violation to PSCM for the exceedances of the selenium <br />effluent limits that occurred at NPDES2 and NPDES4. Although a portion of the bond release area <br />run -off report to Ponds 004 and 002, both ponds and spoil springs SSSPGI, 2, 3, 4, 6 and 6A are not <br />included as apart of the SL -3 application. Sites SSF 11 and SSF 13 downstream of NPDES4 and <br />SSG2 and YSG5 are in compliance with the receiving stream standard for selenium. The CDPHE <br />uses the 85th percentile of dissolved selenium values over the past five years to determine stream <br />attainment of the selenium standard. <br />Permit Requirements of the Colorado Discharge Permit System (CDPS) <br />The Peabody Sage Creek Mine maintains two outfalls which collect runoff from the SL -3 Bond <br />Release area, Pond 002 (NPDES2) and Pond 004 (NPDES4), which are monitored under the CPDS <br />Permit No. CO- 0048275. Pond 2 and Pond 4 are not included in the SL -3 bond release application. <br />Sample data were collected and reviewed for all required parameters and sample analysis included <br />testing for Whole Effluent Toxicity at NPDES2. Sample data have been reported on a quarterly basis <br />in discharge monitoring reports filed with the CDPHE and the CDRMS. These DMRs indicate that <br />one exceedance of permit limits has occurred in the past three water years, with the exception of the <br />selenium standard noted above. The total recoverable iron standard of 1.0 mg /l was exceeded during <br />January 2014 with a value of 1.55 mg /1 at NPDES4. NPDES4 has exceeded this standard only once <br />since monitoring for total recoverable iron was initiated in 1987. The February sample had a total <br />recoverable iron value of 0.11 mg /1. <br />Clean Water Act Effluent Limitations (40 CFR Part 434) <br />Monitoring data for the past three years indicate that the Peabody Sage Creek Mine has not caused <br />