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<br />in early hydrogeology reports by Dr. David Snow (Leeds, Hill, and Jewett, Inc. 1979), which is a <br />result of cross cutting faults and the underground workings add another level of <br />compartmentalization. Review of the water levels in P-7 reveals that the low-flow levels have <br />been relatively consistent since 2001, varying over a very small range from 10,381 to 10,383 <br />feet. Therefore, we believe that the water level in P-7 is not increasing and has reached steady <br />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 monitor <br />bedrock water levels upgradient of the Pinnacle Adit plug, and is closest piezometer to the <br />Chester Fault Zone. P-8 was converted to a dual-purpose inclinometer in 1999 by installing <br />inclinometer casing inside the piezometer casing. P-8 has consistently displayed the lowest water <br />level in the mine vicinity although it has increased approximately 15 feet since 1997, or 1.3 feet <br />per year on average. P-8 is located where the workings once day-lighted in the south wall of the <br />North Pit. Springs occur in this area (CFS and CFS-2) and perhaps the water is slowly filling the <br />secondary porosity in the bedrock resulting in increased water levels in the piezometer. The <br />fractured nature of the rock within the fault zone may also enhance infiltration of water from the <br />springs. Therefore, water in the Pinnacle workings does not appear to be the cause of the slightly <br />increasing water level in P-8. Additionally, precipitation does not appear to be responsible for the <br />increasing water levels because the water level trend has been linear over a 12-year period and <br />one would expect a noticeable change in the rate of increase corresponding to wet or dry years. <br />Flow from the Chester Fault Zone into the North Pit Lake is measured at CFS and CFS-2, which <br />are springs located on the south wall of the pit (Figure 1). The flow from CFS has been measured <br />since fall 1999 and has ranged from 0.5 to 7.2 gpm. The flow from CFS-2 has been measured <br />since fall 2002 and has a similar range from 0.4 to 4.4 gpm. Review of the flow measurements <br />reveals that there is no apparent increase in the flow rate from these springs into the North Pit <br />Lake. A similar consistent flow rate from the Pinnacle Adit has been measured since the adit was <br />plugged in 1995 (Figure 3). Flow rates from the adit during low-flow conditions have ranged from <br />approximately 2 to 8 gpm and there is no noticeable increasing trend. This further supports that <br />steady-state conditions have been reach in the Pinnacle workings. <br />Thank you for your continued cooperation and support of our reclamation and closure activities <br />at the Pitch Project. If you have any questions, please don't hesitate to contact me at (505) 287- <br />4456 x25 or cell (505) 400-2794. Cell is probably the best. <br />Sincerely yours, <br /> <br />HOMESTAKE M/N/NG COMPANY OF CAL/PORN/A <br />Alan D. Cox <br />Attachments: <br />Figure 1 - Site Plan: Pitch Reclamation Project <br />Figure 2 - Water Level Elevation Data in P Wells <br />Figure 3 - Hydrograph of Pinnacle Adit Discharge <br />cc: R. Chase - Barrick-SLC <br />D. Davis - Pitch <br />P. DeDycker - ARCADIS <br />P.O. Box 98 / HIGHWAY 605, GRANTS, NM 87020 Tee: (505) 287-4456 FAX: (505) 287-92B9