Laserfiche WebLink
COLORADO DEPARTMENT OF HEALTH, Warn Quality Control Division <br />Rationale -Page 16, Permit llo. CO-0034142 <br />Table VI-6 - Stanrnary of Mrus Balance CalenlaHons <br /> <br />- .... ...............:... Stmm~.:$/grtdad;:(M3),":.::; <br />..: ::::::. :ArrQe/Clirtinic:.::.:.:.; : ;:;;:!:: ;:'F„Q`luent Concaitiatlari,. {M?); :.: :...:::::.: <br />;.::::::Attire/L7widc:.: : ' ::::;::::::::.::::':. <br />7RC, mgQ 0.011/0.019 41.3/76.4 <br />Arsenic (I), ugR SO/100 371.0/849.0 <br />Cadmium (PDJ, ug/! 9.87/1.13 75.9/9.8 <br />Copper (PD), ugq 17.74/11.82 136.4/102.2 <br />Iron (PD), ug/l NA/300 0~ . <br />Lcad (PDJ, ugQ 50/3.89 384.4/33.6 <br />Manganese (PD), ugR NA/SO NA/355.7 <br />Mercury (TJ, ug/1 2.4/0.01 18.45/0.1 <br />Nickel (PDJ, ugR 922.2/95.58 7088.2/826.3 <br />Silver (PDJ, ug/1 2.03/0.32 15.6/2.8 <br />Zinc (PD), ug/l 117/106 899.5/916.2 <br />(PDJ: Potentially Dissolved <br />t": Both the acute and chronic limitations far potemially dissolved iron wne less than Zno. This rs a result ojthe <br />reponed background concentrations of potentially dissolved iron and total recovnable iron in the receiving stream <br />exceeding the applica4le warn quality standard. 7hnefare, potentialty dissolved iron limitations at OutfalLs 003, <br />022, and 024 will be sn equal to the warn quality criteria for potentially dissolved iron. <br />Total Residual Chlorine: For Outfall 023, effluent limitations jot total residual chlorine, as done in the <br />previous pernw, wne calculated using a design flow of 0.012 MGD, the standard Iisted in section IlI.A.3 <br />of this ratiorutle, and the annual chronic and acute low flows of the Williams Fork River limed in section <br />11/.8.2 of thG• rationale. Since the discharge consisu of domestic wastewatn, no other pollutants except <br />pH, are expected to be present in the discharge. The calculated effluent limit for total residua! chlorine, <br />as shown in Table V/-6, it greater than that a/low,ed by the State Regulations for Effluent Limitations. <br />Therefore the limit of 0.5 mg/I (daily maxirmun) specified in the Regulations shall apply. <br />Total Arrononia: For total arrunonia, the dejauk maximum allowable instream concentrations listed in <br />section IILA.3. wne used as values for Mt in the mass balance equation. The resulting calculated limit <br />for total atturonia !'sited in Table V/-2 is much grearn than any concentration upected to be found in the <br />effluem. In addition, ammonia is not expected to be present in the discharge. Therefore, no limit or <br />monitoring far ammonia will be required. <br />Metals: For metals with dissolved standards, corresponding effluent limits are based upon the potentially <br />dissolved method of analysis. For standards based upon the total and total recoverable methods of <br />analysis, the limits are based upon the same method as the standard, except for arsenic. For arsenic, the <br />total recoverable analysis must be performed using a graphite furnace. <br />