2010-06-03_REVISION - C1996083 - Laserfiche WebLink

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J. J. Dudash -10- June 1, 2010 list of water monitoring sites starting on revised page 2.05-120. The sites located west of Steven's Gulch are ponds 11-8, 12-5 and 12-7, spring 1-8 and pond/spring 28, 29 and 1-10. In addition, there are springs 5-2 and 6-7 along the West Fork of Terror Creek. Should these sites be removed from Map 9 or were they inadvertently left off of the list of monitoring sites? BRL - All of the monitoring points listed are intended to be inactive. All but spring 5-2 are shown in black on Map 9 which indicates an inactive monitoring point. Spring 5-2 was shown in blue but will be changed to black on amended Map 9. The subject monitoring points are outside of the permit boundary and outside the influence of mining. 51. A major concern in reviewing the proposed western mine plan area with regard to potential groundwater impacts is that none of the monitoring wells associated with the Bowie No. 1 mine plan area have been incorporated into the Hydrologic Monitoring Plan for the new expanded Bowie No. 2 permit area as described on page 2.05-117. The proposed plan includes monitoring wells located at the Terror Creek mains and one proposed well down gradient from a portion of the proposed new disturbance. There are essentially no wells included in the hydrologic monitoring plan that would be either directly up gradient or down gradient from the new disturbance associated with the western mine plan proposal. There appears to be numerous inactive wells from the Bowie No. 1 permit area that would be suitable monitoring wells for the new western mine plan area. In addition, several surface water and groundwater monitoring sites are listed in Tables 1, 3 and 4B in Volume 4 of the Bowie No. 1 Mine permit application along with the footnote that monitoring would be reactivated if mining occurred in the east part of the Bowie No. 1 Mine. Please address this and modify the Hydrologic Monitoring Plan accordingly. BRL - There are five Bow-1 monitoring wells in a location that potentially could be used to supplement the Bow-2 Mine's groundwater monitoring. They are DH-47, DH-58, DH-62, DH-69 and DH-70. None of the five holes are completed in the B-Seam or in an aquifer above the B- Seam. DH-47 is screened from 150' to 225' some 1,000 feet above the B-Seam in an unknown formation. DH-58 and DH-69 are screened above, through and below the B-Seam thus mixing the target water monitoring zones. DH-70 is screened below the lower B-Seam in a zone that does not need to be monitored. There is no completion information on DH-62. DH-62 was mined under. 52. The information on revised page 2.05-120 and on Map 9 shows that there is no upstream monitoring site for Steven's Gulch. An upstream monitoring site is needed to compare with the monitoring information gathered at downstream monitoring site SW-5. Please propose a Steven's Gulch upstream monitoring site or explain why such a site is impractical. BRL - It is not practical to have an upstream Stevens Gulch monitoring point because there is no Stevens Gulch stream north of the permit boundary. In the far northwestern edge of the permit boundary, there is a saddle where the drainage flows to the north into the West Fork of Terror Creek. 53. A discussion of the Bruce Park Dam begins on page 2.05-136. The permit text continues to refer to the Bruce Park Dam, while the various permit maps use the name "Terror Creek Reservoir". In the interest of clarity, please consider adding, "and Bruce Park Dam" to the feature on the various maps and/or modify the permit text to explain that the reservoir formed by the Dam is the Terror Creek Reservoir.