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aquitard. The dry mine workings are 500 feet above the top of the Navajo sandstone that is considered <br />an aquifer in the region and up to 900 feet above the lower part of the Navajo where any groundwater <br />is likely to exist. A part of this separation (approximately 100 feet) is the aquitard Summerville <br />Formation. The interbedded mudstones within the Salt Wash are also considered aquitards. Therefore, <br />water quality of the Navajo groundwater (if present) is not important since it will not be impacted by the <br />mining operation. No groundwater monitoring program is needed due to the dry condition at the mine. <br />10. Surface Water Control and Containment Information <br />The mine site is more than 6 miles from the Dolores River. The drainage connection between the mine <br />and the Dolores River is ephemeral for the entire length. The surface water control aspect of this EPP <br />has three components: <br />The natural terrain and historic drill roads uphill of the mine indicate that very little surface flow <br />runs onto the site. A water bar will be installed on the access road east (uphill) of the top of the <br />waste rock pile to reduce the amount of stormwater from running onto the waste rock pile. The <br />location of the water bar is shown on the map, Figure 2. The integrity of this water bar will be <br />monitored for damage due to traffic or storm events and repaired as needed. <br />A berm will be constructed on the outside (downhill) edge of the top of the waste rock pile. This <br />berm will be 2 feet high and will contain the precipitation that falls on the top of the pile. This will <br />also reduce the amount of water that will flow onto the slope of the waste rock pile. The location of <br />the berm is shown on the map, Figure 2. <br />A liner will be placed under the ore stockpile area that will contain any precipitation that falls on <br />the material contained in the ore stockpile. A low berm around this liner will prevent water from <br />running onto the ore stockpile liner. The berm will also make the liner a zero discharge facility. The <br />design of the liner is discussed in Appendix U -2. All other chemicals or materials used on site (fuel, <br />oil and grease, antifreeze, etc.) will be stored in secondary containment structures. <br />11. Surface Water Quality Data <br />Since the only flowing stream (Dolores River) is greater than 6 miles from the site, no surface water <br />quality data is included with the EPP. <br />12. Water Quality Monitoring Plan <br />No surface water monitoring program is needed due to the prevailing dry conditions and intermittent <br />(ephemeral) nature of the surface flows of the drainage between the mine and the Dolores River, <br />greater than 6 miles away. The mine workings are dry and expected to remain that way as future <br />expansion occurs. No water will be discharged from the site. The only potential groundwater sources <br />within two miles of the site are either stratigraphically above and isolated from the mine horizon or <br />hundreds of feet beneath the mine. Therefore, no groundwater monitoring plan is needed. <br />7 <br />