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

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Schwartzwalder Mine -Hydrologic Study of Mine Closure and Reclamation
6. SURFACE WATER QUALITY .............................................................................................................43
6.1 Surface Water Quality Standards ........................................................................ .................44
6.1.1 Discharge Permit Limits ........................................................................ .................44
44
6.1.2 Stream Standards ................................................................................... .................
6.2 Previous Studies of Surface Water Quality ........................................................ .................48
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6 Surface Water Sample Stations ........................................................................... .................48
. 6.3.1 Compliance Monitoring Stations ........................................................... .................48
48
6.3.2 Additional Non-Routine Sampling ........................................................ .................
49
6.3.3 1998 - 1999 Baseline StudyData ........................................................... .................
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6 Potential Loading Sources .................................................................................. .................50
. 6.4.1 Upgradient Sources ............................................................................... ..................50
...50
6.4.2 Alluvium and Fill .................................................................................. ...............
..50
6.4.3 Mineralized Bedrock ............................................................................. ................

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Ralston Creek Water uali ............................... .......................
Q ty ..................... .. 52
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1 Water Quality During Operation of the Sumps and WTP ....................
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5 53
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6.5.2 Water Quality After Turning off the Sumps and WTP ......................... ..................53
7. GROUNDWATER QUALITY ...............................................................................................................91
7.1 Groundwater Quality Standards and Point of Compliance ............................... ...................92
7.2 Alluvial Water Quality ......................................................................................
94
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7.3 Sump Water Quality ......................................................................................... .................115
7.4 Seep Water Quality ........................................................................................... .................115
7.5 Shallow Bedrock Water Quality ....................................................................... .................119
7.6 Underground Mine Water Quality .................................................................... .................120
7.6.1 Deep Mine Water ................................................................................. .................121
....125
7.6.2 Shallow Mine Water ........................................................................... ..............
127
7.6.3 Water Quality in the Reflooded Mine .................................................
1 Evaluation of Mine Water Mine Water Quality with Depth .
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..................130
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2 Evaluation of Chemical Trends in Mine Water as a Function of Time ...130
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7.6.3.3 Concentration Correlation Plots ............................................. ..................139
8. CHARACTERIZATION OF WASTE ROCK AND FILL .................................... ...............................140
8.1 Whole Rock Analysis ......................................................................... ...............................140
8.2 Acid-Base Accounting ....................................................................... ................................141
8.3 Acid Consumption Tests .................................................................... ................................142
................142
9. IMPACT ANALYSIS ........................................................................................... ................
9.1 Waste Rock Piles ............................................................................... ................................142
9.2 Alluvium and Fill ............................................................................... ................................144
.............145
9.3 Mine Refilling .................................................................................... ...................
Whetstone Associates •
4109B.071116