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previously NPDES4-Data provided for this Bond Release Application reflect NPDES4 and not <br />NPDESS or NPDES6. Parameters monitored are provided in Tables 6 and 9 for outfalls 002 <br />and 004. Sample analysis has included testing for Whole Effluent Toxicity at NPDES2 (WET <br />testing is no longer required at NPDES4). Sample data has been reported quarterly in discharge <br />monitoring reports (DMRs) filed with the CDPHE and the CDRMS. These DMRs indicate that <br />no exceedances of permit limits (with the exception of selenium, previously discussed) have <br />occurred in the past five years. However, asample from NPDES4 (1/8/2014) had a TR iron <br />value of 1.55 mg/l. The limit in the CPDS permit is 1 mg/l. The 1.55 value is an anomaly; <br />NPDES4 has exceeded this standard only once since monitoring for TR iron began in 1987 <br />(4/7/2005 with a value of 1.47). The 2/13/14 sample had a TR value of 0.11 mg/1. <br />D) Clean Water Act Effluent Limitations (40 CFR Part 434) <br />Monitoring data for five years provided in Tables 6 and 9 indicate the mine has not caused <br />exceedances of either limitation identified in 40 CFR Part 434 that is applicable to reclamation <br />areas on coal mines (settleable solids (STS) of 0.5 ml/l and pH of 6.0 to 9.0). PSCM records STS <br />values that it measures monthly for these outfalls and documented in the field notebook. Only <br />values that are at or above the detection limit, 0.4 ml/1, are entered in to PSCM's water quality <br />database. The absence of those values on Tables 6 and 9 indicates that no samples were measured <br />at or above the detection limit. <br />E) Impacts to Alluvial Valley Floors (AVFs) <br />There are two potential AVFs in the Grassy Creek basin. They include a 45 acre parcel near the <br />confluence of Little Grassy Creek and Grassy Creek and a 40 acre parcel along Little Grassy <br />Creek. Per the CDRMS (1/28/2009 email from Tom Kaldenbach), these two parcels are <br />`grandfathered' (per Rule 4.24.3(4)) and are exempt, and are not evaluated. <br />An AVF is present in the Fish Creek basin downstream of PSCM Outfall 004. It was originally <br />discussed on page 7-279, Tab 7 of the Seneca II Mine permit package, which identifies an AVF <br />where irrigation was practiced on Fish Creek from the point where Cow Camp Creek is confluent <br />with Fish Creek down to where Fish Creek is confluent with Trout Creek. This 63 acre parcel is <br />located downstream of the confluence with Bond Creek. However, the irrigation ditch for this <br />33 <br />