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Matthew S. Hayes June 28, 1989 Page 10 The addition of the new monitoring well will make the total B seam wells number 4 as follows: Well Description SOM 23-H-2 E Seam Coal SOM 127-H B Seam Coal SOM C-72-H Lower Coal Member (immediately above the B seam) SOM 128-H (new) As determined during drilling In addition to these wells aze all of the F seam monitoring wells in the Upper Coal Member and F coal seam, numbering 19. Due to the overall general knowledge of the hydrologic regime in the Mt. Gunnison mine block, we feel this is entirely sufficient to monitor for B seam mining. 3. a. It appears that the PVC casing in well SOM 23-H-1 was fractured or split by a nearby landslide movement. It also appears that better quality alluvial water is seeping into the casing, diluting the B seam water and changing the well head. WECC plans to discontinue monitoring this well for B seam purposes. Historical data from this well obtained in 1977, should represent accurately the conditions existing in the B seam. Groundwater which is associated with downwazd gradient movement is typically high in TDS due to contact with strata in the Mesaverde as opposed to water which moves locally through the alluvium and fractures associated with surface runoff which is lower in TDS and generally of better quality. b. High pH in well C-72-H may be due to grout used during comple- tion of the well. Although the pH is high, well C-72-H will continue to be used as a B seam monitoring well. WECC will flush the well utilizing drilling equipment in conjunction with drilling of the additional B seam well. Hydrologic consultants from Geowest, as well as WECC geologists, feel that the high pH, if grout related, can be remedied by flushing with water and jetting the well dry.