Laserfiche WebLink
COLORADO DEPARTMENT OF HEALTH, Water Quality Con[ro! Division <br />Rnrionnlc - Pn~e l!. Permit No. CO-0032638 <br />S. Calculation of Water Oualirv-Based Ellluent Limitations <br />A mass balance equation was used to determine the effluent concentrations that would nor violate the <br />allowable in-stream concentrations defined by the water quality smndards (except in the case of pH, where <br />the limits arc set directly from stream standards or effluent regulations without using a mass balance <br />approach). 7hc mass balance equation is: <br />M, _ <br />MJQt- M~Qr <br />Q: <br />Where: <br />Qt = Upstream low flow (7QI0) from Pan I/1.B.2 <br />Q= = Average daily e~ttuu.llmv (design rnpaeity) <br />Qr = Combinod downstream flow (Qt + QrJ <br />Mt Upsutam background pollutant c»ncentration from /!/.B. I <br />Mr Unkrwwn; Mmumum allowable ejfiuent pollutant croneentration calculated using mass balance equation <br />Mr Maximum downstream alloxuhk pollutant aancentration (stream standard) <br />Because of the mathematical relationship between Jbw, pollutant rnncentration and pollutant mass, <br />concentration linutations taaleulated «sing this merlwd implicitly limit instream pollutant mass ro the nraxinuttn <br />allowable kveL Also, only flow and twncentration limitations need to be sped in the pcrnut. Mass <br />limitations are not required A sununnry of the mass balance tnkv/ations (tf any) are shown and discussed in <br />VLA.3. <br />6. Discrtrsion of Efjlttent Limitations <br />a LteRUlations for E1Ruem Limitations: The Regulations for Ejjhtent <br />Limitations (10.1.0). apply to the aanventional pollutants For this facility, as was done in the previous <br />permit, the limitations for Oil and Create at all Outfallr 001, 002, 003, 004, 005, and 006 are bared on <br />this regulation. <br />b. Aoolitaabk Federal E/Ruem Guidelines and Standards: 71u federal guidelines x~tich aPPh' to ~' tYPe of <br />fatality are found under 40 CF7e Pan 434, titled Coal Mining Poiu Souroe Category BPT, BAT, BCT <br />Limitations and New Souroe Paformtuux Standards The lintitatians rdtidt apply arc: <br />Table V/ - 4 - Fedcml Standards <br />Iron, total 3. S mgA 7.0 mgR <br />TSS 35 mg/l 70 mg/l <br />Settleable Solids NA 0.5 m!/1 <br />pH Buwren 6 0 su and 9.0 su <br />