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water levels recorded for this well appear to reflect the fact that <br />• the well has subsided but do not indicate that dewaterinq of the <br />alluvium has occurred. The changes during late October and into <br />November appear to reflect seasonal changes and changes which can <br />be attributed to subsidence. The water level in the well appears <br />to have stabilized since first being subsided. The water quality, <br />as reflected by the field parameters, does not show any significant <br />variation which could be attributed to subsidence. <br />Well GWAP7, like the above well, started showing subsidence during <br />October, with 2.0 feet of subsidence being reported for this well <br />on October 18, 1993. By the end of the year the well had subsided <br />a total of 2.2 feet. The water levels recorded for this well <br />appear to reflect the fact that the well has subsided but do not <br />indicate that dewaterinq of the alluvium has occurred. The changes <br />during late October and into November appear to reflect seasonal <br />changes and changes which can be attributed to subsidence. The <br />water level in the well appears to have stabilized since first <br />being subsided. <br />Well GWB2, like the above well, started showing subsidence during <br />October, with 2.4 feet of subsidence being reported for this well <br />on October 18, 1993. The well had to be replaced on December 13 <br />due to pinching off of the well casing. it appears the well <br />pinched off at the contact between the sandstone and a shale. When <br />the well was first completed the water well was reported above <br />ground elevation. However, during the mining process the shallow <br />• sandstone was dewatered and the water level as of December 30, 1993 <br />was measured at 35.8 feet below the measuring point. During the <br />last week of the year the water level appears to have stabilized <br />and may be showing signs of recovering. The water quality, as <br />reflected in the field parameters, does not appear to have been <br />impacted by the well subsiding. Normal seasonal variation is <br />reflected in the data presented on table 52. <br />Well GWB1, like well GWB2 and GWB2R, is also completed in the <br />shallow sandstone. This well is located outside of the subsided <br />area but has shown a decline in the water elevation during this <br />half of the year. The data indicate that the well has stabilized <br />and appears to be recovering. The water quality data does not <br />appear to have been impacted by the sandstone unit subsiding. <br />4.0 CHANNEL PROFILE <br />The Fish Creek channel was surveyed prior to subsiding the area and <br />the results of the survey are presented on Figure 1. In addition <br />to the premining survey a survey was conducted during November, <br />1993 which showed the extent of subsidence within the channel. <br />Selected sections of the channel has subsided by approximately 1.5 <br />feet, which is within the predicted range presented in Twentymile's <br />permit. Visual observations of the channel, bank and valley floor <br />have not revealed any significant impacts resulting from subsiding <br />• the sections of the creek. The hydrologic data presented on tables <br />53 and 54 due not reflect a degradation in water quality due to <br />