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To supplement this study, data was collected for the same time period for Palisade Annual Rainfall <br />and Mesa Lakes Annual Snowpack. Data for the Palisade Annual Rainfall was collected from the <br />Western Regional Climate Center, Palisade Station #056266, which is the closest station to the mine <br />site. The location for this station is shown as Latitude 39.1080560, Longitude -108.350556°, which <br />is approximately 3 miles southwest of Rapid Creek. The annual mean precipitation for this site varied <br />from 5.28 inches to 15.28 inches. Recorded rainfall for this area shows a downward trend from 1986 <br />to 2012 as depicted on the Palisade Annual Rainfall diagram in Attachment 8. Data for the Mesa <br />Lakes Annual Snowpack was collected from NOAA — Colorado Basin River Forecast Center, Mesa <br />Lakes Station MESC2. The annual snowpack for this site varied from 10 inches SWE (snow water <br />equivalent) to 33.1 inches SWE with a downward trend from 1987 to 2012 as depicted on the Mesa <br />lakes Annual Snowpack diagram also contained in Attachment 9. <br />Data from Rapid Creek monitoring site SWGS O1, along with both of the flow comparisons (Colorado <br />River and Plateau Creek) and the rainfall and snowpack data, show downward trends in flow, rainfall <br />and snow accumulation from 1986 to 2012. Based on this data, SCC concluded that the slight <br />downward trend of flow in Rapid Creek was most likely caused by climatic conditions as opposed to <br />subsidence effects. It is also important to note the flow in these creeks is largely controlled by the <br />City of Palisade, depending upon their need for domestic water. Also, irrigation water is diverted <br />from the creeks by private water right holders at various locations. <br />Portions of Cottonwood and Rapid Creeks were undermined above their confluence, with depths to <br />the underground workings ranging from about 300 feet to 460 feet below ground surface. A portion <br />of Rapid Creek below the confluence was undermined, with the depth to the underground workings <br />being about 170 feet below ground surface (at SWGS-01). Subsidence cracks extending towards the <br />surface could potentially affect the flow in these Creeks and cause a sudden loss of water. The <br />Division does not believe this is the case based on our review of available groundwater information <br />and water level data. To try and determine if there is a loss of water in Rapid and Cottonwood Creeks <br />due to subsidence from coal removal beneath the creeks, the Division reviewed the Roadside Mine <br />Plan for Alluvial Ground Water Monitoring of Rapid and Cottonwood Creeks which was submitted <br />in response to Stipulation No. 6, dated March 7, 1983. This plan contains the well construction detail <br />for six alluvial monitoring wells and is included as Attachment 10. In summary, there are three <br />groundwater monitoring stations: one up gradient on Cottonwood Creek, one up gradient on Rapid <br />Creek, and one down gradient below the confluence of the two creeks (see Attachment 8 for <br />locations). Each station contains two separately constructed wells for a total of six wells. Each well <br />was completed and cased to bedrock. Well A at each station was drilled to bedrock and constructed <br />with a perforated interval only in the lowermost portion of the alluvium. Well B was constructed with <br />perforated casing along the entire depth of alluvium. The Division concludes that the wells were <br />properly designed and constructed and water level monitoring data presented to date is accurate. <br />Water level data were reviewed for the period from 1984 to present. The ground water monitoring <br />points on Cottonwood and Rapid Creeks are monitored twice during the Water Year. Results of the <br />monitoring taken from the 2013 AHR are provided as Attachment 11. Included in Attachment 10 are <br />Diagrams G13-1 thru 3 showing a graphical representation of the depth to water for these wells since <br />monitoring began in 1984. Table G13-1 is also included in Attachment 11 and was prepared by SCC <br />to show average water levels in the spring and fall to correspond with high and low water levels in <br />the adjacent creeks respectively. There appears to be little impact on Rapid and Cottonwood Creeks <br />Page 28 <br />