2021-03-15_REVISION - C1981044 (2)

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Manual of the mining permit. Ground Water Impacts One bedrock well (83-02), exists down the hill and to the north of the Utah Tract,monitoring water levels in the mine relative to subsided areas. Wells 83-02 and TR-7a monitor the Middle Sandstone formation. A second bedrock ground water well TR-7a, exists to the west and south of the Strip Pit. Well TR-7a is within the expected flow path of mine leachate. Well TR-7a data indicates the parameters monitored are within their baseline water quality levels. The pH levels at this well fluctuated above and below the drinking water standard but within the baseline levels. Water levels are trending upwards. The upward trend may be attributed to the cessation of mining and dewatering activities. There are no water quality monitoring wells in the bond release blocks. Surface Water Impacts The four permitted ponds located in the Strip Pit Area rarely hold water. Sediment ponds at the site generally only hold a small amount of water for a short period of time between March and June. Permanent pond PA-PI is the only pond to have a record of discharge, and has not discharged since 1990. Structures have been designed as per the permit to contain the requisite flood events. Division reviews indicate that there have been no water quality problems at these ponds. A spoil spring,No 1 Strip Pit, outfall 022,is monitored for NPDES parameters. The spring generally discharges as a result of snowmelt form March through June. Total dissolved solids, and iron concentrations have trended upwards since 2002 with levels remaining within historic ranges. Surface sampling site Y-2 is located to the west of the Strip Pit. This site has a quarterly sampling requirement of water quality parameters. No significant,unpredicted or adverse environmental impacts to water quality have been noted based on review of the 2019 AHR. Utah Tract Cover and Species Composition The reclamation standard for cover in both 2014 and 2015 have been met in the Utah Tract for Range Sites A and B as discussed above. Production The sample mean was greater than 90%of the reclamation standard but, sample adequacy was not achieved in either Range Sites A, B or Reference Area 3 in 2014 or 2015. Therefore, a t-test of the reverse null hypothesis, described in Rule 4.15.11(2)(c), was used to demonstrate reclamation success for both range sites in 2014 and 2015. The reverse null hypothesis was rejected and for Range Site A in 2014 and 2015. Allowable production in 2014 for the area was 1459.7 lbs/acre, in 2015 allowable production was 11010.0 lbs/acre, again exceeding 90% standard of 500.9 lbs/acre. Permit Number C1981044 Page 22 of 25