2010-03-08_REPORT - C1996083 (5)

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water contents as the working faces moves further from water sources. There was a water inflow of approximately 5 gal/min one year prior. Monitoring site No. 3B is located in the B9 headgate inby of cross cut 7, in entry #2 by 50 ft. The steady flow of 60 gal/min has a conductivity of 4.9 mS/cm. The water, with a pH of 7.9, is consistently warm with an in-situ field temperature of 33 degrees Celsius. The steady flow of water seen here is consistent with the water trends seen near the working faces, where ground water penetrates through the exposed fractures, joints, faults, and drill holes. The sample was taken on 07/07/09 at 10:00 am. Monitoring site No. 4 is located in the wet conditions of the B8 headgate, entry No. 1, in cross cut 11 (see Location #4). The water sample taken on 07/07/09 at 11:00 had an estimated flow rate of approximately 80 gal/min. The water sample taken at this location came from an open joint in the rib that had a consistent and high flow rate. The clear water sample taken at this location had a pH of 8.0 and was fairly warm with a temperature of 32 degrees Celsius. There was no evidence of suspended solids and had a conductivity of 4.7 mS/cm. Monitoring site No. 5 is located in the B8 headgate at cross cut 11, in entry No. 1 (see Location #5). The water sample taken on 07/07/09 was warm with a temperature of 31 degrees Celsius and a heavy flow rate of 110 gal/min. This sample had a normal pH of 8.4 and a conductivity of 5.0 mS/cm. This water sample was taken from an open joint near the roof on the rib, at 12:00 pm, and had no appearance of suspended solids. Monitoring site No. 6 is located in the B8 tailgate at cross cut 10, in entry #3. This damp location had a high flow rate of 85 gal/min. The water sample was taken from a source that was flowing from a bolt support holding up a water hose. There was a conductivity of 2.3 mS/cm and pH of 8.0. The water found at this location was relatively warm with a temperature of 30 degrees Celsius and was taken on 07/07/09 at 10:32. Sampling Protocol: According to the Hydrologic monitoring Plan 2.05.6 of the Permit Application Coal Mining in Colorado, Volume I Text, the mine inflow sampling frequency should be measured annually. The results of the inflow parameter testing should be recorded in the annual hydrologic report. In order to be in compliance with the Hydrologic Monitoring Plan, the next date of field and lab parameter testing should take place on or before the 16th of July in 2010. The annual sampling frequency allows for the complete analysis of the impact of mining on the hydrologic balance. Sampling Measurements and Procedures: In order to obtain accurate and consistent field testing results, appropriate procedures should be followed. When determining the flow rate, one of the two methods should be used. The first method is to calculate the flow rate by using the flow rate equation of Q=VA. A, being the cross sectional area of the nozzle/source of water, and V being the known velocity at the nozzle. The other method is to use a portable 60 degree V-notch weir. When taking field measurements using a pH and conductivity meter, it is good practice to clean each meter prior to in-situ tests, using a rinse, as to not have any contamination affecting the final results. Likewise, the pH and conductivity meter should each be appropriately calibrated before performing field measurements. For water inflow measurements, the pH meter should be calibrated to either 7 or 10. When capturing the water sample for lab parameter testing, it is necessary to rinse the container being used to make sure no contamination is involved. When collecting the water sample, it is 2