Laserfiche WebLink
i <br />i <br />1 <br /> <br /> <br /> <br /> <br />1 <br />1 <br />1 <br />n <br />U <br /> <br /> <br />1 <br /> <br /> <br />i~ <br />The approximate 100-yr flood limits in Rite Seco in the <br />vicinity of the proposed mine are shown on Figure G-8. The <br />depth of flow, used to draw the limits of inundation was <br />estimated by calculating individual rating curves at 14 cross- <br />section locations. The approximate limits of inundation between <br />cross-sections were estimated by assuming a uniform water <br />surface between cross-sections. <br />Based upon engineering judgment, a constant Manning's <br />"n" of 0.10 was used for each cross section. <br />G.2.4 Minimum Streamflow Standards on Rito Seco <br />According to the Colorado Water Conservation Board's <br />(CWCB) Instream Flow Appropriations table for [ii vision III <br />(Ruth Yeager, CWCB), there are currently no minimum Streamflow <br />standards for Rito Seco, either through the reach near the <br />mine site or anywhere within the Rito Seco drainage basin. <br />This table is included as Appendix K. <br />G.2.5 Surface Water Quality <br />To date, eight sets of baseline water quality data have <br />been obtained from the existing surface water st~~tions. With <br />the exception of the radiological data from the .ianuary 1989 <br />samples, all of the analytical results have been received. <br />Water quality data for each surface water <:tation are <br />summarized in chronological order in Tables G.2-6 through <br />G.2-9. <br />Water quality data obtained from Rito Seco and its <br />tributaries indicate a predominantly calcium-bicarbonate type <br />water. There is little indication of metals with tFe exception <br />of consistently high iron concentrations. ThE data for <br />monitoring site RS-3 indicate a generally poorer water quality <br />than the other two surface water stations sampled. Station RS- <br />G-22 <br />