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Comments Submitted by Denver Water <br />August 20, 2010 <br />a way that the location of Ralston Creek was altered. The existence of these features has <br />the effect of pollutants being discharged at multiple points. The WQA and Permit <br />development is based upon a single point of discharge and both documents should be <br />revised to reflect multiple discharge points <br />2. Description under Figure A-1. The description of the study area from a mining and <br />reclamation perspective is absent and needs to be included. The Schwartzwalder Mine <br />site has pollutant sources impacting Ralston Creek located at the mine pool, in alluvial <br />fill areas, from seeps in the alluvial fill area, and from waste rock piles. It is important to <br />document that portions of past reclamation strategy have been determined to have failed <br />and that new reclamation approaches are being re-evaluated by DRNIS and re-instituted <br />by the permittee as a result of water quality impacts. <br />3. Description under Figure A-1. The description of the study area from a water supply <br />perspective is not quite correct and needs to be revised. The diversion at the Long Lake <br />Feeder Ditch Headgate into Upper and Lower Long Lakes occurs approximately 1 to 1- <br />1/4 miles upstream of Ralston Reservoir, which is approximately 3/ to 1 mile <br />downstream from Outfall No. 001. A portion of Ralston Creek is diverted at the Long <br />Lake Feeder Ditch Headgate and supplies Upper and Lower Long Lakes on the Ralston <br />Reservoir property and Vern Lake on Arvada's Long Lake Ranch Park. Water diverted <br />at this headgate is used for irrigation and not for water supply and there isn't a return of <br />this water to Ralston Creek or any other Creek. Long Lake Ranch Park is open space <br />property with public access. <br />4. Table Value Standards and Hardness Calculations. The hardness value used for the <br />calculation of table value standards should be based on upstream water quality data, <br />which may be available from USGS, Cotter, Denver Water and others. The use of <br />hardness values from downstream locations reflects a degraded condition of the water <br />quality in Ralston Creek and results in higher permit effluent limits than is appropriate to <br />restore water quality. The use of downstream hardness values promotes the continued