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This amendment addresses the proposed subgrade repository to be used to <br />store the subgrade ore until such time it can be processed economically. The <br />subgrade repository exists as an historic crosscut behind the underground <br />milling area. This portion of the underground workings is on a slight incline <br />allowing for the collection of 'fluid' portions within the lower area (immediately <br />adjacent to the underground mill), and allowing for milling water to decant for <br />recirculation. This portion of the repository will be lined with a geotextile pond <br />liner, and retained behind a bulkhead (approximately 5-6 feet tall). The entire <br />repository is an historic cross-cut tunnel approximately 1000 feet long at the <br />same elevation as the underground mill (10,844 ft elevation) with a slight <br />ascension towards the top due to the incline grade. This elevation is over 100 <br />feet above the water level in the mine (10, 690 ft elevation). Since it is a cross <br />cut, there is no 'economic mineral' in this underground working. Given these <br />site setting features, the repository provides a comprehensive 'vacuole' to <br />contain the subgrade ore. There is a minimal amount of water present, and the <br />introduced water from the milling is actively re-circulated. Since this repository <br />cross cut is not flooded, the only water to be concerned about is associated with <br />the water from the subgrade ore itself. With the presence of the liner, and the <br />recirculation of the water-there should be minimal to no head pressure, <br />therefore minimal to no transfer of water to underlying workings. If water does <br />transport via fractures to underlying features, it is likely the water will seek a <br />path of least resistance and end up in the lower workings of the mine itself. If it <br />does, then this water will be captured by the CDPS discharge, and controlled as <br />per the CDPS permit conditions. From this perspective, any water associated <br />with the subgrade repository is captured and held in control. As a conservative <br />measure, the Ruby Trust will conduct sampling of the subgrade material on a <br />routine basis in order to test the geochemical character and be sure the <br />subgrade ore does not contain acid- or toxic-character. If either of these <br />characteristics are detected, production of ore will cease until such time <br />appropriate controls are put into place. Therefore in summary, there should be <br />no impact to groundwater as a result of this proposed process. Further detail is <br />provided in Section 2 below. <br />As per the Mineral Rules for the protection of groundwater, the proposed <br />milling process will adhere to State-wide groundwater quality standards. As per <br />assessment by CDWR, the Ruby Trust occurs within an 'unclassified area' <br />meaning the groundwater (likely due to lack of sufficient quantity) has not been <br />given a defined use. Regardless, under the 'antidegradation' clause of the Clean <br />Water Act, the proposed process should not introduce any anthropogenic <br />contaminants of concern. The proposed milling relies strictly on gravimetric <br />separation methods and therefore does not 'introduce' any anthropogenic <br />6