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• f' ~ U '.0 Nedra(ogir Dara lnrrrprrration and lmpaR .iuarmrnt for the Prrmir and Adjarrnr Arrar appear to be unaffected by mining activities until the extraction of coal breaches the well, such as demonstrated in Well SOM-C- 72-H. Monitoring within the Jumbo Mountain tract included three decreed springs: #22 (Jumbo Mountain site 15), #23 (Jumbo Mountain site 18), and CR-12 (decreed Spring #12). Water migration in the coal seam, and in the underlying and overlying formation, is very low; the boundazy formations aze relatively impermeable. The coal seam carries little water due to low quantities of water available for recharge. Ia summary, there is a low impact on the water regime of the mined and adjacent azeas. 2.2 ASSESSMENT OF SPRINGS MCC monitored twenty-six springs during the WY. May flows at all springs totalled 772 gpm (1.72 cfs), while June flows a[ all springs totalled 421 gpm (0.94 cfs). Flows at the Jumbo Mountain sites were lower in June than May, while the reverse held true for other sites. Flows from springs were far above average, reflecting the high precipitation levels. Five sites with flows greater than 50 gpm contributed 486 gpm or sixty-three percent of the total flow in May. These sites were G-22, and Jumbo Mountain sites 4, 5, 15, and 18. Ten of the twenty-six springs monitored have a relatively constant flow while sixteen springs show defutite seasonal variation. With the exception of Springs G-I2 and G- 20, springs aze consistently responsive to spring runoff. The flow rates of springs G- 12 and G-20 (too low to sample in 1995) aze sporadic and many times do not correlate well with other seasonal parameters such as snowpack, precipitation, or streamflow. Af~t~93.:10105/IS/96f I:JBpml Six springs had one or more water quality parameters outside baseline ranges. This reflects the limited duration of baseline spring monitoring rather than any impact from mining. No impact from mining activities on springs is expected if the mine workings aze not hy- draulically connected. For example, ground subsidence (transmission of cracks up through the overburden from settlement) might impact the integrity of a groundwater regime. None of the data on monitored springs and seeps distant from underground mining activities suggests an impact from mining activities. Springs nearby underground mining activities aze Jumbo Mountain resource numbers 6 (shown as decreed spring 14 on Exhibit 2), 3 (shown as decreed spring 18 on E.ektibit 2), 9 (shown as decreed spring 19 on Exhibit 2), 15 (shown as decreed spring 22 on Exhibit 2), and springs G-20 and G-25. The data on these springs suggest no impact from underground mining activities. Monitored springs underlain or in close proximity to the underground mining activities are Jumbo Mountain resource numbers 4 (shown as decreed spring 17 on Exhibit 2), 5 {shown as decreed spring 16 on Exhibit 2), (17) (shown as G-30 on Exhibit 2), 18 [shown as decreed spring 23 and spring G-31 (appears as G-3 due to overstrike by a symbol) on Exhibit 2], 20 (also listed as G-28 or G-28a), spring G-26A, and spring G-26B. Data on one of these springs, Spring G-26B, suggests a possible impact from underground mining 16 REVISED 09P_7/96