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Minrec, Incorporated Water Quality Assessment CO- 0048233 the regulation states that this requirement may be waived where the salt load reaching the mainstem ofthe Colorado River is less than 1 ton per day, or less than 366 tons per year. The Division may permit the discharge of salt upon a satisfactory demonstration that it is not practicable to prevent the discharge of all salt. See Regulation 61.8(2)(1)(i)(A)(1) for more information regarding this demonstration. For municipal dischargers, an incremental increase of 400 mg /l above the flow weighted averaged salinity of the intake water supply is allowed. This may be waived where the salt load reaching the mainstem of the Colorado River is less than 1 ton per day, or less than 366 tons per year. The Division may permit the discharge of salt in excess of the 400 mg /l incremental increase, upon a satisfactory demonstration that it is not practicable to attain this limit. See Regulation 61.8(2)(1)(vi)(A)(1) for more information regarding this demonstration. Regulation 75 contains requirements for the release of water from Cheraw Lake. Any entity releasing water from Cheraw Lake must ensure that either: 1) the water has a TDS concentration less than or equal to 4300 mg /1, or 2) that an adequate quantity of water of less saline nature can be supplied for dilution purposes such that a salinity level of 4300 ppm, measured as TDS, can be maintained in Horse Creek immediately above the first diversion below the confluence with the Cheraw Lake outlet channel. In addition, the Division's policy, Implementing Narrative Standards in Discharge Permits for the Protection of Irrigated Crops, may be applied to discharges where an agricultural water intake exists downstream of a discharge point. Limitations for electrical conductivity, sodium absorption ratio, or sodium, may be applied in accordance with this policy. Temperature Temperature shall maintain a normal pattern of diurnal and seasonal fluctuations with no abrupt changes and shall have no increase in temperature of a magnitude, rate, and duration deemed deleterious to the resident aquatic life. This standard shall not be interpreted or applied in a manner inconsistent with section 25 -8 -104, C.R.S. Segment specific Cold Stream Tier I numeric standards have been developed for segment COUCRFIO and are June - September MWAT = 17.0 C with the DM = 21.2 C, and October -May MWAT =9.0 C with the DM 13.00. Segment Specific Numeric Standards Numeric standards are developed on a basin - specific basis and are adopted for particular stream segments by the Water Quality Control Commission. To simplify the listing of the segment- specific standards, many of the aquatic life standards are contained in a table at the beginning of each chapter of the regulations. The standards in Table A -3 have been assigned to stream segment COUCRF 10 in accordance with the Classifications and Numeric Standards for the Upper Colorado River Basin. Appendix A (WQa v 7.0) Page 6 of 25 Last Revised Sept 14, 2009 /ES