1986-03-03_REPORT - C1981013 (4)

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3. Removing the chart from the recorder indicating the station, date, time, stage height, and initials of the person servicing the recorder; and 4. Back-flushing the inlet pipe to prevent sediment build-up and clogging. 2.2 Ground Water Monthly ground water samplings were-conducted at each of the eight designated stations PAW-1, PAW-2, PAW-3, PAW-4, PAW-5, PAW-6, CCAW-1 and ACAW-1 during the last week of each month. The Purgatoire alluvial wells PAW-1, PAW-2, PAW-5 and PAW-6 have been in place for a number of years. Stations CCAW-1 and ACAW-1 were completed during April 1984 while PAW-3 and PAW-4 were completed in April 1985. Depths to water below the top of the well casing was measured to the nearest hundredth-foot using an electric line water level detector. The elevation at the top of the well casing was subtracted from the depth to water to obtain the ground water level below the ground surface. Water quality was sampled in the field directly from the wells with a hand bailer. The wells were cleared by bailing at least three columns of water prior to collecting the sample. Equipment and procedures used for water chemistry analysis were consistent with those described above for Surface Water. 3.0 MONITORING RESULTS The geologic setting is an important factor when analyzing hydrology of an area. Stratigraphy in the region ranges in age from Pre-Cambrian to Quarternary. However, only the Raton Formation and Quarternary (alluvial) deposits are exposed in the area of the mines. The Raton Formation constitutes the bedrock of the area having a total thickness of 1200 to 1600 feet. Most of the formation consists of very fine to medium grained sandstone interbedded with siltstone and shale. Coal to be mined at the New Elk and Golden Eagle is located near the middle of the Raton Formation. The outcrop of the formation in the area may be characterized as stream deposits including channel-point bar facies, floodplain deposits and swamp deposits. -8-