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,a <br />The results of the modeling suggest that it could take up to 1,000 years for water to travel <br />from the waste dump to the water table, if it is 400 feet below. Therefore, in addition to <br />the above mentioned well (or in lieu of the above mentioned well if the perched Salt <br />Wash aquifer is found to be dry at that location), Cotter proposes a soil water sampler <br />(lysimeter) be installed It will be neaz, and on the down-gradient side of the waste rock <br />dump, while still allowing for dump expansion. The approximate location of the <br />proposed lysimeter was discussed with DMG during the field meeting, and is shown on <br />the attached map. This will serve as a timely sampling system showing the amount and <br />quality of water percolating through the dump material. <br />The installation plans for the lysimeter aze as shown on the attached "OPERATING <br />INSTRUCTIONS FOR SOILMOISTURE EQUIPMENT CORPORATION MODEL <br />1920 F1 PRESSURE-VACUUM SOIL WATER SAMPLERS". <br />The monitoring schedule for the lysimeter installation will be to sample on a monthly <br />basis as long as adequate sample quantities can be collected, to establish a baseline set of <br />data. Following the initial collection efforts sampling may be reduced to a quarterly basis <br />depending on the concentrations of the potential contaminants in the samples. <br />Also included with this information is a report from GeoScience Services titled "The role <br />of fractures in unsaturated transport". This report discusses how the faults and fractures <br />in the azea of the JD-9 mine waste dump should limit the transportation of potential <br />contaminants from the mine waste material. <br />The other aspect being addressed is the impact of underground mining operations (and <br />the closure of the underground mine) on the perched groundwater. Cotter is not presently <br />impacting the perched groundwater quality since water entering the mine is pumped, <br />treated, and discharged. It is Cotter's contention that the perched water is limited in <br />aerial extent, has extremely low flow rates due to limited recharge, low permeability, and <br />the lack of hydraulic forces due to a flat dip, and is of poor quality. To test the validity of <br />these azguments, Cotter has sampled the groundwater entering the mine, azea seeps and <br />springs, and will sample the proposed well. Preliminary results have been received. This <br />information will chazacterize the groundwater quality. Furthermore, possible age dating <br />and flow measurements in the well might determine the rate and direction of groundwater <br />movement, which will be useful in evaluating the possible impact to the perched water <br />currently and once pumping ceases. <br />The Division's determination (Third Review from Harry Posey and Kate Pickford to <br />Russ Means, March 6, 2006) that the JD-9 Mine is a DMO because "re-flooding of <br />underground workings with perched aquifer water from the Salt Wash formation would <br />have the potential to violate state-wide standards" is "based on SPLP results". Cotter <br />does not believe that the acid solution used in the SPLP test represents the leaching <br />potential of the groundwater in the mine. Therefore, Cotter has completed a bottle roll <br />tests on materials representative of rock exposed in the underground workings using Salt <br />Wash goundwater. Preliminary results of this test were just received. As soon as we <br />have an opportunity to review these results we will forwazd the results to the Division. <br />JD-9 geo_Isup - 2 - <br />