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B. EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
<br />1. $ffluent Limitations
<br />b. Post-Mining Ouffalls
<br />PART 1
<br />Pagc No. 5
<br />Permit No. COG-850000
<br />Post-mining limitations may apply to ouffalls serving surface azeas, which have been retttmed to the required contour and on which
<br />revegetation (specifically, seeding or plantiag) work has commenced. The permittee may request consideration for change from
<br />active mining limitations topost-mining limitations when these conditions have been met.
<br />POST-MINING PRIMARY LIMITATIONS
<br />Flow, MGD
<br />'Settleable Solids, rnl/1
<br />pH, s.u.
<br />Oil and Grease, mgR
<br />Total Dissolved Solids, mg/1••
<br />Total Phosphorus (as P), mg/1•••
<br />5Li-+' 3 ~ ~ 1.-g?~.,w8'~t+t.,z u..;c ~-aan _~. -
<br />. -._,n.~-''~a'~..~f.:t;1...:.=~, ~~ .~'~.'~ ~~r~LtmrtahOn -.~e:.,.....,_ .. ~..~.. w.
<br />Report
<br />0.5
<br />6.5-9.0
<br />10
<br />Report
<br />Report
<br />POST-MINING ALTERNATE LIMITATIONS
<br />Any dischazge or increase in the volume of a discharge caused by precipitation within any 24-hour period greater than the I 0-yeaz,
<br />24-hourprecioitation event (or snowmelt of equivalent volume) »~ comply with the following limitations -- subject to burden of
<br />proof requirements descnbed in Part I.B.l.d).
<br />~,. _.
<br />
<br />~y=~. ..-,~. ... _..~:~arameter ~ ~
<br />- ..~.
<br />,___-ria~. ? `~.~:.d.vas_...,~~.-~~... xT.invtauon_ ~„<,...,~ _. ~.~.
<br />Flow, MGD Report
<br />•Settleable Solids, mUl Report
<br />pH, s.u. 6.5-9.0
<br />Oi] and Grease, mg/1 10
<br />Total Dissolved Solids, mg/l•• Report
<br />Total Phosphorus (as P), mg/1••" Report
<br />•If discharge is to land, TSS and settleable solids monitoring is waved. ''Applies only to drainages within the Colorado River Basin
<br />'''Applies only to drainages directly above Cha~eld Reservoir, Cherry Creek Resmorr, Dillon Resrnoir, a Upper Bear Creek
<br />c. Genera] Limitations -Active and Post-Mining Outfalls
<br />1) There shall be no dischazge of sanitary wastewaters from toilets or related facilities.
<br />2) There shall be no dischazge of floating solids or visible foam in other than trace amounts.
<br />3) There shall be no land application of wastewater other than for dust control.
<br />4) No chemicals shall be added to the dischazge unless the Division grants specific approval
<br />d. Btuden of Proof Reauvements
<br />The permittee has the burden of proof when requesting relief from total suspended solids (TSS), total iron, total manganese, and/or
<br />settleable solids limitations. Relief shall be gtanted only when necessary and shall not be granted when the pertrtittee has control
<br />over the discharge. The petmittee should endeavor to meet the primary limitations whenever posstble. The Division shall have final
<br />authority in determ;n;r,g whether relief is granted.
<br />1) For rainfall, to waive TSS, total iron, and total manganese limitations, it is necessary to demonstrate that dischazge occurred
<br />within 48 hotus after measurable precipitation has stopped. To waive settleable solids limitations, it is necessary to prove that
<br />dischazge occtrred within 48 hotus after precipitation greater than the 10-yeaz, 24-hour event has stopped.
<br />2) For snowmelt, to waive TSS, total iron, and total manganese limitations, it is necessary to demonstrate that discharge occurred
<br />within 48 hotus after pond inflow has stopped. To waive settleable solids limitations, it is necessary to prove that dischazge
<br />occtured within 48 hours after pond inflow volume greater than the ]0-yeaz, 24-hour event has stopped.
<br />The Division shall determine the adequacy of proof. As part of this determination, the Division shall evaluate whether the petmittee
<br />could have controlled the dischazge in such a manner that primary limitations could have been met. All manual dewatering of ponds
<br />that are equipped wiUt automatic dewatering systems must meet TSS, total 'son, and total manganese limitations. If a pond has only
<br />manual dewateting capability, relief is available only to the extent required to regain necessary stability and capacity.
<br />See Part I.C. for Definitions
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