2009-04-13_REPORT - C1996083 (5)

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value was recorded at 9, with a 4.3 mS/cm conductivity. The hand measured temperature observation of the water was of room temperature with a flow rate estimate of approximately 1/4 a gallon per minute. Monitoring Site No. 3 was picked due to its correspondence along the D5 fault in the 2'd North Mains between cross cuts 6 and 7 in entry No. 2 (see Sample Location 3). The water sample taken at this monitoring location is in the middle of the sloping incline of the No. 2 entry towards the B8 Headgate. This sample location shows a consistent amount of water diipping off the rib mesh, which is coming from a roof bolt. The water sample taken on 7/16/08 at 11:20 is clear with no suspended sediment. This approximate estimated flow rate of this dripper is .17 gallons per minute. The combination of drippers along both sides of the rib near this sample location would allow for a much higher estimated flow rate. The recorded pil value for this sample location was 8.4 with a 4.9 mS/cm conductivity. Monitoring Site No. 4 is located in the extremely wet conditions of B8 Headgate, entry No. I in cross cut 11 (sec Sample Location 4). The water sample taken on 7/16/08 at 11:45 had an estimated flow rate of approximately 5 gallons per minute. This site proved to show the fastest flow rate seen throughout the mine. The water sample taken at this location came from a crack in the wall that had a consistent and high flow rate. There was evidence of higher flowing springs coming out of open joints and cracks under unsupported roof with lots of water pooling up near the face in this particular entry. The clear water sample taken at this location had a pH of 8.2 and conductivity of 4,8 mS/em with no evidence of suspended sediment. 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 16`" of July in 2009. 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 two methods should be used. The flt'st method is to record the amount of time it takes to fill a container of known size, and 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 off the each meter prior to each test 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 7 and 10. When capturing the water sample for lab parameter testing, it is necessary to rinse the container being used multiple times to make sure no contaminate is captured. When collecting the water sample in the appropriate container, fill the container up as much as possible as to limit the amount of air captured, minimizing oxidation. Also, a standard mercury thermometer is recommended to take the necessary temperature measurements during field testing. Sample Handling: