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<br /> <br />Mr. Darry Ferguson -5- February 18, 1993 <br />Geochemistry <br />1. Geochemistry information was acquired from three holes with <br />composite samples averaging more than 30' in thickness. As <br />our guidelines recommend 4' intervals, please re-sample the <br />geological column at the site. Hopefully, the cores were <br />organized at some location. If not, please drill three new <br />holes. <br />2. The results of a substantial drilling program are presented <br />in Appendix 4-3. Seventeen holes were drilled of which five <br />had significant amounts of water during drilling. Water <br />appeared to overlie the coal seams; it was initially <br />observed in these wells approximately 15' above the Upper <br />Shamrock, in the Shamrock-Carbonera sequence, and then in <br />the sandstone above the Lewis Coal. Six holes went down <br />into the Pictured Cliffs Sandstone a short distance, but <br />drill logs are available for seven logs for which there is <br />no location. Please reconnoiter all holes remaining on the <br />site to see if water came in after drilling. Static water <br />levels are 226'-330' above the bottom of the holes. <br />3. Some water quality information has been acquired from three <br />springs over the last nine years. Two of the springs <br />discharge small volumes of water ( 5 g.p.m.) throughout the <br />year and discharge higher volumes in response to <br />precipitation events. Salinity, as reflected by TDS, varies <br />from 180 mg/1 to 4,275 mg/1, suggesting different sources. <br />These springs reflect unconfined yet reliable sources of <br />water; the permit indicates that they and other springs <br />supply the canyon with some of their flow. Please provide <br />full suite monitoring on the springs to better characterize <br />them; information in the permit is restricted to field <br />parameters and TDS. <br />4. Well B-17 is on the northeastern end of the permit area. It <br />produces a moderately alkaline and saline (TDS = 400 mg/1), <br />sodium bicarbonate water with low hardness. It is 165' <br />deep, and its perforated interval intersects the Lewis Coal, <br />and zones 15' higher and lower than the coal, 20'-60' below <br />the surface. The water level has ranged from the ground <br />surface to 12' below the surface. The Division is concerned <br />that this well has flowed out from the top of the hole. <br />Please put a valve on it if such is the case. <br />