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peak water level in the piezometers was missed as the new site manager, Dale <br />Davis, was getting familiar with the site conditions and the required monitoring <br />program. <br />Piezometers located within the Pinnacle workings include P-4 and P-5. P-9 is <br />located downgradient of the Pinnacle workings and also monitors water levels within <br />the workings. Piezometers located upgradient of the Pinnacle workings (and <br />Pinnacle Adit plug) include P-7, P-8, and P-10; these piezometers are not within the <br />workings. <br />Piezometers that monitor water levels in the underground mine workings (P-4, P-5, <br />and P-9) have very similar since 1997. Spring and summertime water levels may <br />vary from year to year due to the magnitude and timing of snowmelt and heavy <br />summer precipitation event; however, water levels during low-flow conditions since <br />1997 (i.e., over-the-winter) have consistently been between 10,391 to 10,397 ft-amsl. <br />Water levels during low-flow conditions should be considered when assessing trends <br />and indicate that there is no increasing trend for the Pinnacle workings. Based on the <br />available data since 1997, the water level in the workings has essentially reached <br />steady state. <br />Piezometer P-7 is designed to monitor bedrock water levels upgradient of in the <br />Pinnacle Adit plug. As shown on Figure 4, the water levels in P-7 are approximately <br />10 to 15 feet below the level in the Pinnacle workings and follow the same seasonal <br />water level patterns as the piezometers that are within the workings, suggesting that <br />P-7 is somewhat hydraulically connected to with the workings. The slightly lower <br />water level is due to the complex geology and hydrogeology at the Pitch site. <br />Groundwater is compartmentalized, as documented in early hydrogeology reports by <br />Dr. David Snow (Leeds, Hill, and Jewett, Inc. 1979), which is a result of cross cutting <br />faults and the underground workings add another level of compartmentalization. <br />Review of the water levels in P-7 reveals that the low-flow levels have been relatively <br />consistent since 2001, varying over a very small range from 10,381 to 10,383 feet. <br />Therefore, we believe that the water level in P-7 is not increasing and has reached <br />steady state similar to the water level within the Pinnacle workings. <br />Piezometer P-8 lies just to the north of the Pinnacle workings and was constructed to <br />monitor bedrock water levels upgradient of the Pinnacle Adit plug, and is closest <br />piezometer to the Chester Fault Zone. P-8 was converted to a dual-purpose <br />inclinometer in 1999 by installing inclinometer casing inside the piezometer casing. <br />P-8 has consistently displayed the lowest water level in the mine vicinity although it <br />Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />2010 Annual <br />Reclamation Report <br />21