Laserfiche WebLink
<br />COLORADO DEPART.`SENT OF HEALTH <br />Water Quality Control Division <br />Rationale - Page 2 <br />Permit No. CO-0035653 <br />FACILITY DESCRIPTION: <br />The Grassy Gap Coal Mine was formerly know as the Grassy Creek Coal `tine. <br />vas renamed about two years ago. <br />Most of the mine is in the reclamation phase. Only pit number 4 remains <br />active, although no mining Sa currently taking place. Outfall number 001 <br />serves pit tl4, Pit Y4 is expected to remain active for about three years. <br />Pits 1, 2, 3, 5 and 6 have been reclaimed. Surface areas have been <br />recontoured, and revegetation has been occurring for about a year. <br />All autfalls (001-005) are the outfall structures from sedimentation ponds, <br />all of which will contain the volume generated by the 10-year, 24-hour <br />precipitation event. <br />APPLICABLE RULES AND REGULATIONS: <br />It <br />Table 1 below, shove State Effluent Standards (SES), Federal Beat Practicable <br />Control Technology (BPT), Federal Best Available Technology Economically <br />Achievable (BAT) and State Water Quality Standards (WQS) applicable to outfall <br />001. <br />TABLE 1 <br />Parameter SES SS BPT BAT <br />pH, e.u. a/ 6.0 - 9.0 6.5 - 9.0 6.0 - 9.0 N/A. <br />011 and Grease, mg/1 a/ 10.0 N/A N/A N/A <br />Total Suspended Solids, mg/1 30/45 d/ N/A 35/70 b/ N/A <br />Total Iron, mg/1 N/A N/A 3.5/7.0 b/ 3.5/7.0 <br />Settleable Solids, ml/1 c/ N/A N/A N/A 0,5 <br />a/ This parameter applicable at all times <br />b/ Thia limitation applicable to discharges during periods of no preciptitation <br />c/ Thia parameter applicable to discharges during periods of precipitation less <br />than or equal to the 10-year, 24-hour event for this facility <br />d/ Thia limitation does not apply pureuant~to Section 10.1.3(3) of the State <br />Regulations for Effluent Limitations <br />