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999 <br />Memorandum <br />To: Jerry Koblitz <br />From: Mazc Sydnor <br />Subject: Lorencito Canyon Hydrologic Monitoring Program <br />Drilling at this site has been completed and as such, this is a summary of the program to date. A <br />total of 10 alluvial wells have been installed and tested via the Bouwer and Rice slug test method. <br />All wells penetrate lithologies with similaz properties and all results show alluvium. Six pad sites <br />were selected for the installation of monitoring wells. The wells were installed in sets (three to each <br />site) and the same horizons were selected at each site. A total of 17 deep wells have been installed <br />to monitor the Ciruela and Primero coals. These wells were installed with one well installed in the <br />overburden of the coal, one in the coal, and one in interburden below the coal. Overburden and <br />underburden monitoring horizons were selected based upon the nearest likely water bearing zone <br />above and below the coal zones. <br />Very little water was encountered in the wells installed azound the Ciruela coal zone and many were <br />drilled strictly with air. Two well locations MW1 and MW1A encountered water during drilling, <br />however; this water was less than 5 gallons per minute. Further testing of the wells showed that the <br />zones surrounding the Ciruela coal were not aquifers, and the Ciruela itself exhibited water only in <br />the one MW ] location. Testmg of the overburden well at the MW 1 site did not develop a hydraulic <br />conductivity since the slug introduced into the well did not result in a falling head for over an eight- <br />hourduration. "the MW 1 well installed in the coal exhibited a transmissivty that was approximately <br />1.3 ft-/day. This value is rated as infeasible too poor for constructing a domestic well within this <br />zone. Since an aquifer is "a body of rock of that is sufficiently permeable to conduct ground water <br />and yield economically significant quantities of water to wells and springs" then both the Ciruela <br />coal and the surrounding strata would not be considered aquifers. <br />One well pad drilled into the Ciruela Coal (pad MW3) was discontinued during the drilling since <br />water in the wells drilled previously indicated that no aquifers exist. Wells on pad MWl north of <br />the site are dry, and the boring and subsequent well at the MW3 site is also dry. Additionally, as <br />previously discussed, the only wells in the zone with water have transmissivity values that are not <br />considered to be aquifers, therefore; groundwater issues for the Cireula coal and associated <br />overburden and interburden are not considered consequential. <br />Drilling in the Primero encountered water in moderate qualities (20 gpm from alluvium) at the MW4 <br />pad site. All strat below the alluvium drilled dry. Pad site MW6 was also dry. A notable exception <br />to dry drilling was MWS. At this site a shallow zone (perched or potentially alluvial) was <br />encountered that produced up to 175 gallons per minute from 50 feet below surface. This water is <br />thought to be originating from the runoff in Alamosa canyon. Further up the canyon, surficial water <br />is present that enters the subsurface west of the proposed permit boundary. East of the drill site <br />