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LKA International Inc. <br />Golden Wonder/ Level 6/ Hydrologic Setting Executive Summary <br />Executive Summary <br />The hydrologic setting of Level 6 of the Golden Wonder mine at Gold Hill has been the <br />subject of regulatory interest due to the presence of groundwater seeps and other <br />ephemeral flows in Deadman Gulch. Level 6 includes approximately 1 acre of surface <br />disturbance comprised of a functional mine portal and working pad. These features are <br />immediately adjacent to Deadman Gulch. The working pad contains waste rock <br />historically produced from the mine's underground workings, including, but not limited <br />to, Level 6. The waste rock is largely comprised of rhyolite rock which predominates <br />throughout Gold Hill and has the potential to generate acid. The purpose of the studies <br />summarized in this document is to assess whether the water quality of one or more <br />groundwater seeps located at the toe of the waste rock or other ephemeral flow in <br />Deadman Gulch is affected by the waste rock. <br />The Hydrologic setting of Level 6 is fairly complex as a result of topographic influences <br />and underlying groundwater systems associated with distinct geologic layers and <br />formations. Studies completed to date indicate there are two groundwater systems - one <br />associated with spring melt flows that saturate porous surface alluvium and the second <br />associated with underlying fractured rhyolite that is also affected by spring melt - and <br />ephemeral surface water flow that occurs as a result of the two groundwater sources <br />reaching surface expression points created by the geologic formation itself (i.e. seeps). <br />This water can be channeled into fault systems such as Deadman Gulch and the historic <br />collapse fault that connects to Deadman Gulch. The existence of the fault systems <br />(associated with Deadman Gulch and the historic collapse) has been verified with <br />geologic mapping, and water quality studies in mine features on either side of the fault <br />(water quality from the Golden Quartz, Dawn of New Hope and the LKA No. 2 well). <br />The observation in Spring 2008 of seep flows at the toe of the waste rock pad with flow <br />rates greater than 200 gpm provided the first true indication that the sources of water in <br />the seeps are more than just upstream flows in the channel or underground sump or other <br />water from the mine. At the time of these significant flows, Deadman Gulch was <br />hydrologically contained within a geotextile channel isolating other surface flows away <br />from the seeps and the underground mine workings were virtually dry. As a result of <br />these conditions, it was apparent a significant groundwater source is the source of water <br />in the seeps. These observations (by LKA Int., Richmont Mines Inc., BLM and DBMS) <br />led to the hypothesis that the site setting needs further study with the use of distinct <br />piezometer wells designed to sample the distinct geologic formations associated with the <br />I