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through 1999. As the mine was being developed to the south, thirty-six (36) mine inflow points were <br />identified. The measured mine inflow varied over the period of record from a low of around 100 <br />gallons per minute to over 350 gallons per minute. During the final two years of the mine inflow <br />studies (1998 and 1999), mine inflows were measured at 326 and 302 gallons per minute, respectively. <br />Most of the water inflow comes from the south end of the mine as shown on Attachment 12 - Roadside <br />South Mine Inflow Map. <br />The majority of the mine inflow originated from the following three locations when the mine portals <br />were sealed in April of 2000. <br />Monitoring Location <br />1998 Flow <br />1999 Flow <br />Average <br />03 <br />50.4 <br />38.5 <br />44.4 <br />33 <br />244 <br />244 <br />244 <br />34 <br />24.3 <br />18.8 <br />16.6 <br />Totals m) <br />318.7 <br />301.3 <br />305.0 <br />Monitoring Location Description: <br />03 - No. 1 South Mains near No. 1 East Mains - flow from 2nd West Panel Seals <br />33 - 4 South Mains at Rapid Creek Mains, inflow from floor and ribs in 4 South Mains <br />34 - 2 South Mains Seals below 5 East Mains includes flow from former locations 24, 25 and 27-31. <br />All of the mine inflows flow down dip to the mined out workings at the north end of the mine. This <br />large mined out area is referred to in the permit as the northwest intake pool. An angled hole was <br />drilled into the northwest intake pool so water can flow by gravity from the mine. An eight -inch <br />diameter pipe was installed in the angled hole. Discharge from the northwest intake pool averaged <br />279 gpm during the 2013 Water Year. This discharge rate compares favorably with the preceding <br />mine inflow estimates. <br />A close inspection of the mine workings by SCC showed that no secondary mining occurred under <br />Rapid Creek or Cottonwood Creek except for the 3rd East Panel which was mined out in August <br />1982. There are no mine inflows associated with the panel and mining apparently did not affect Rapid <br />Creek. The mine inflow rate has remained steady from late in the mine's operation to present day. <br />This suggests that the origin of the water is produced from the underground formation (groundwater <br />seepage) into the mined out workings, which is recharged at the surface some distance up gradient <br />from the mine. An additional significant source of seepage into the mine workings is perched or semi - <br />confined groundwater. The Division concludes that the source of the water discharging from the 016 <br />Outfall is groundwater inflow to the mine not directly related to Cottonwood and Rapid Creeks. <br />SCC has performed a study of the discharge from Outfall 016 to determine if it has been impacted <br />historically by the irrigation season which would suggest communication between water placed at the <br />surface and the mine inflow water that discharges at Outfall 016. To determine if there was an <br />increase in discharge from Outfall 016 when irrigation season was at its peak, SCC compiled a set of <br />flow trend graphs comparing the discharge from December -January 2003-2012 (no irrigation) to <br />June -July 2003-2012 (peak irrigation season). The data show remarkable consistency between the <br />two seasons with discharge remaining between 250-300 gpm for all measurements and there was no <br />Page 30 <br />