2010-02-22_REPORT - C1981038 (5)

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during 2009 for water levels and field parameters when water is available. Well SM-1 is next to areas mined in 1991 and 1992 but showed no apparent impacts in the field data collected during 2009. Well SM-9 was undermined by Panel C during 1993 but showed no apparent impacts in the field data collected during 2009. No anomalous water quality observations were apparent during 2009 at the Stevens Gulch shallow groundwater monitoring wells. Surface Water Monitoring Stations - SPRINGS East Roatcap Creek- Two springs were monitored in the East Roatcap Creek drainage (refer to Table 1 and Map No. 4-1) during 2009. Spring 30 had flows that were near average during the year. Spring 30 was first undermined in April 1983. Spring 10-10 was dry during the reporting period. Spring 10-10 was encompassed by the angle-of-draw of Panel Y during October 1993. Subsidence impacts were not apparent at either of these locations during 2009. West Roatcap Creek- Two springs were monitored in the West Roatcap Creek drainage (refer to Table 1 and Map No. 4-1) during 2009. Spring 32 was monitored twelve times during the year. Spring 32 exhibited flows that were below average. Water quality parameters were consistent with last years sampling. Spring 14-4 was monitored quarterly. Flows were considered normal. No mining occurred during 2009 in the Spring-14-4 watershed. Stevens Gulch - One spring was monitored within the Stevens Gulch drainage (refer to Table 1 and Map No. 4-1) in 2009. Spring 25 lies below an area of the East mine inactive since 1982. This site had no measurable flows in May, June, August or November. Spring 25 has been identified as an adjudicated water right within the permit area. Two springs with ponds in the Stevens Gulch drainage, Spring and Pond 13-5, Spring and Pond 13-6 were monitored quarterly in 2009. Spring and Pond 13-5 was undermined during the last half of 1992. Spring and Pond 13-6 was undermined during the end of 1988. Spring 13-5 was reported as a seep during May and was 40 dry or damp during June, August and November. Spring 13-6 had measurable flow during May and was reported as a seep during June, August and November Terror Creek- There is one spring monitored within the Terror Creek drainage (refer to Table 1 and Map No. 4-1) and it was monitored during 2009. Spring and Pond 20 was undermined during the East Pod development, panels EP-3 and EP-4. The spring has extensive data collected to characterize the typical hydrology. This location was identified and targeted by the DBMS as adjudicated water right within the permit area. No adverse mine related impacts or other irregularities were noted at this Terror Creek Spring. Surface Water Monitoring Stations: STREAMS AND DITCHES Overall, adverse impacts attributable to mining were not evident at any of the monitored surface water stations (refer to Table 1 and Map No. 4-1). Stations SW-5 (Stevens Gulch) and SW-6 (East Roatcap Creek) exhibited flows and water quality parameters consistent with previous years data. Station SW-10 (Terror Ditch) exhibited typical flows for an irrigation ditch. No evidence of subsidence impacts in these drainages was apparent. Mining occurred in the Stevens Gulch drainage upstream of site SW-5 during 1993 in Panel C. Panel C mining was designed and conducted to prevent the development of subsidence to protect the waterway and certain structures in the vicinity. Data collected during 2009 shows these protective measures were successful. Surface Water Monitoring Stations: SMALL AREA EXEMPTIONS The east mine fan level was defined as a small area exemption since drainage from this area (refer to Map 8- 1) is not conveyed to a sediment pond. Three sample points were defined at this location and sampled for conformance with the NPDES discharge alternative limitations requirements associated with discharges occurring because of precipitation events of less than the 10-year and 24-hour magnitude. In these instances, settable solids and pH limitation must be met. No samples were collected during 2009 from these SAE points. • 3