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flow is significantly larger than the Tuttle Draw flow) the impact is negligible. <br />During periods of irrigation, Tuttle Draw is flowing at a higher rate while the River <br />is running low, which is the time of maximum impact of the spoil water flows. <br />During this period of time, the increase in TDS of the River ranges from 620 to <br />652 ppm, or. an increase of 5.1 %. It should be noted that Tuttle Draw flows are <br />always higher in TDS than the River, regardless of the spoil springs, therefore, the <br />impact from the spoil springs may a 2 to 3% increase in TDS. During <br />March/April, the river is flowing fast and Tuttle Draw is at low flow, therefore the <br />increase in TDS for the river is only 2 ppm, or an increase of 0.4%. Also, these <br />impacts are for the time when the spoil material is leaching salts at a maximum. As <br />described earlier, the TDS levels will drop as pyrite and salts are leached out of the <br />spoil, lessening the impact to the waters downstream even further. <br />Calamity Draw is not included in the above table since the spoil springs from both <br />mine areas will not enter this stream. This intermittent stream should not be <br />affected in the long term by the mining and reclamation operation. <br />Overall, the. effects of the spoil springs are not significant to the waters <br />downstream., <br />All probable impacts have been determined to be of a relative short-term nature, of <br />minimal significance, or a plan has been presented to mitigate those determined to <br />have some significance. As a result, mining affects to current land uses should be <br />minimal. A;detailed report is included in Section 2.04.7 and Table 2.05.6(3)-1 of <br />the permit application. <br />III. Topsoil <br />A. Within the NH-1 permit block, topsoiling operations have been fully completed. <br />Topsoil was' generally replaced in approximate thickness of 1.0 feet on dryland <br />pastures and 1.5 feet on irrigated pastures, dependent upon the actual amount of <br />topsoil recovered. <br />In the NH-2 permit block, topsoiling operations have been completed in the eastern <br />portions of the area, and are on-going on areas to the west of 2700 road, as the <br />mine operations advance to the west. <br />Soil stripping and replacement practices have been revised a number of times <br />subsequent to initiation of operations in 1992, most recently by TR-57, approved in <br />early 2009. ;Soil baseline information including soil survey results, soil analyses, <br />and salvage projections are contained in Section 2.04.9 (Soils Resource <br />Information) of the permit application. Map 2.04.9-1 (Soil Baseline Map-New <br />Horizon 2 Mine) delineates soil units based on soil surveys contracted by the <br />operator. Map 2.04.9-2 (Topsoil Balance Map As Of February 2008) depicts the <br />status of soil salvage, replacement, and stockpiling operations as of February, <br />36