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STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman St., Room 215 Denver, Colorado 80203 Phone: (303) 866-3567 FAX: (303) 832-8106 April 22, 2002 Jim Stover, P.E. J.E. Stover & Associates 2768 Compass Drive, Suite 101 Grand Junction, Colorado 81506 RE: 2000 Annual Report, Bowie No. 1 Mine, Permit No. C-81-038, Bowie Resources Limited. Dear Mr, Stover: Df VISION OI MINERAL`. GEOLOGY REC LAM ATIOh MININ G•SAFE7Y BiII Owens Governor Greg E Watcher Executive Director Michael B. Long Division Director The Division has reviewed Bowie Resources submittal for the 2000 Annual Report. This adequacy review letter is divided into three sections, the 2000 Annual Hydrology Report, the 2000 Annual Mine Inflow Report and the 2000 Annual Subsidence Report. The Division has the following comments and questions concerning the hydrology report and has comments concerning the mine inflow and subsidence reports: 2000 Annual Hydrologv Report The Division agrees with BRL's summary of the results of the surface water and ground water monitoring. In general, there do not appear to be any results which are out of line with the historic hydrology data. There are quite a few monitoring locations that have dried up. The years 1998, 1999 and 2000 have been drier than normal and have contributed to the drying up of some seeps and ponds. Precipitation for 2000 was 11.87 inches, while the average precipitation is 15.26 inches. There are some monitoring results which warrant a closer look. As discussed in the report, sulfate levels at ground water well B07 rose to 410 mg/1 from last yeaz's value of 350 mg/1. Sulfate values at this location have been higher in the past and the current value is close to the baseline average of 302 mg/1. Since this well is important as a down gradient monitoring paint for the east mine, continued scrutiny is called for. In addition, the Division notes other increases at other locations. Conductivity and TDS at monitoring well SM-11, located in the alluvium/colluviumfust north of the west mine bench area, appear to be showing a general trend upward since 1994. However, the historic values for conductivity and TDS at SM-11 were similar in magnitude for the period from 1986 to 1989. Conductivity and TDS at SM-11 for 2000 were 2370 umhos/cm and 1550 mg/1 respectively. Monitoring point SM-10, located close to SM-11 in the same alluviaUcolluvial deposits, also was showing an increase in conductivity and TDS from 1990 to 1998, although at a higher peak magnitude than at SM-Ll. However, since then, the values have come down considerably. Future monitoring data will reveal if the increase at SM-11 continues to a point of concern. Surface water monitoring location S W06 showed a conductivity level of 1200 umhos and a TDS level of 830 mg/1 for 2000. Although these values are somewhat high, the historic data show similaz values. The 2000 data and the historic data both show that the values fluctuate greatly within the same year.