2007-11-07_HYDROLOGY - M1977300

• Permit No: M1977300
• IBM Index Class Name: HYDROLOGY
• Doc Date: 11/7/2007
• Doc Name: Hydrologic evaluation of mine closure & reclamation
• From: Whetstone Associates
• To: Cotter Corpoartion
• Media Type: D
• Archive: No

1V
Schwartzwalder Mine -Hydrologic Study of Mine Closure and Reclamation
Table 11. Completion Data for Alluvial Monitoring Wells .......................................................................... 21
21
Table 12. Summary of Single Well Permeability Tests in Alluvium ...........................................................
.......... 24
Table 13. Sump Pumping Rates ............... ..................................................................
........................
Average Monthly Inflow to the Mine from Infiltration of Precipitation, 1995 - 1999 .................
Table 14
31
.
Table 15. Average Rate of Water Level Rise in Mine Shaft ........................................................................ 36
38
Table 16. Mine Void Volumes and Observed Inflow Rates During Refilling .............................................. 40
Table 17. Calculation of Final Static Water Level in the Flooded Mine ...................................................... 41
Table 18. Summary of Isotopic Data for Water Samples .............................................................................
......... 44
................................
Table 19. Discharge Permit Effluent Limitations ...............................................
ination of Hardness Values Used in Calculating Hardness-Based Aquatic Standards .....
t
D
0
46
erm
e
.
Table 2
Table 21. Water Quality Standards for Ralston Creek Stream Segment 17b ...............................................47
49
Table 22. Compliance Monitoring Stations and Non-Routine Sampling Stations in Ralston Creek............
49
Surface Water Quality Sampling Stations From the 1998-1999 Baseline Hydrology Study ......
ble 23
T .
.
a
Table 24. Water Quality in Ralston Creek, 1998 - 2007 ..............................................................................
with Location in Ralston Creek, November 1998 ....................
ter Qualit
f W
i .62
88
y
a
son o
Table 25. Compar
::: :
Table 26. Uranium Concentrations in Ralston Creek, 1990 - 2007 .........................................................
91
Table 27. Location and Frequency of Groundwater Quality Samples .........................................................
.. .
.93
Table 28. Groundwater Quality Standards .................................................................................................
.. .97
Table 29. Water Quality in the Alluvium ..................................................................................................
........... 116
Table 30. Water Quality in the Sumps .............................................................................................
Table 31. Uranium Concentrations in Sumps and Seep, 1998 - 2007 ........................................................ 117
119
Table 32. Water Quality in Shallow Bedrock ............................................................................................. 121
Table 33. Locations of Underground Water Quality Samples .................................................................... 123
Table 34. Water Quality at Underground Sampling Stations in the Lower Mine Levels ........................... 125
Table 35. Flow Rates at Underground Sampling Stations in the Upper Mine Levels ................................ 127
Table 36. Water Quality at Underground Sampling Stations in the Upper Mine Levels ........................... 129
Table 37 Summary Statistics for Water Samples Collected from Flooded Mine ....................................... 140
Table 38. Summary of Geochemical Characterization Data for Waste Rock and Fill ............................... 141
Table 39. Average Mineral and Chemical Analyses of Schwartzwalder Rocks ......................................... 142
Table 40. Summary of Acid-Base Accounting Results .............................................................................. 147
Table 41. Average Water Quality for Samples Collected from Deep Mine Workings ............................... 148
Table 42. Weighted Average Water Quality for the Upper Mine Workings ..............................................
149
Table 43. Controlling Mineral Phases in Deep Mine Water ...................................................................... .
150
Table 44. Controlling Mineral Phases in Flooded Mine Water ................................................................. .
150
Table 45. Effect of pH and Eh on Controlling Mineral Phases .................................................................
....... .
.152
Table 46. Summary of Reclamation Activities ...................................................................................
LIST OF FIGURES
p .....................
Figure 1. Schwartzwalder Mine Location Ma •••••••••••••••••••••••••••••••••••••••••""""""""""""""""2
Figure 2. Locations of Monitoring Wells and Surface Water Stations near the Mine Site .............................6
Figure 3. Generalized Geologic Map .....................................................~..................
......................... 7
Figure 4. Detailed Geologic Map of a Portion of the Ralston Butte 7.5 Quad .....................
Figure 5. Cross Section Showing Mine Workings, Major Fault Systems, and Underground Water Sample
Locations ............................y ......................................................................10
................................
Figure 6. Average Flow Rates in Ralston Creek vs. Monthl Mean Precipitation .............................
Figure 7. Flow Rates Measured in Ralston Creek near the Schwartzwalder Mine, by Month, 1998 - 1999 13
Figure 8. Flow Rates Measured in Ralston Creek near the Schwartzwalder Mine, by Station, 1998 - 199914
Whetstone Associates
4109B.071116