2010-04-20_REVISION - M1977300 ‎(8)‎

• Permit No: M1977300
• IBM Index Class Name: REVISION
• Doc Date: 4/20/2010
• Doc Name: 11
• From: Whetstone
• To: DRMS
• Type & Sequence: TR11
• Media Type: D
• Archive: No

Environmental Protection Plan, Schwartzwalder Mine 11-3
Methodologies for Surface Water," Document 5 CCR 1002-31, Table III, footnote (3). At Station SW-
BPL, the low-flow season occurs between July and February. Hardness values were calculated from
magnesium and calcium concentrations, and the calculated values were similar to laboratory-determined
hardness values, when reported by the lab. Because values for many analytes, including calcium and
magnesium, were different before and after the sump shut-off, only data from post sump shut-off were used
to determine the mean hardness value used in the numeric criteria calculations. Calculated hardness values
for these distinct periods are presented in Table 11-2.
Table 11-2. Hardness Values Used in Calculating Hardness-Based Aquatic Standards
•
•
Pre sum shut-off
Calculated
Hardness,
mg/L as
Date CaCO3 Post sum shut-off
Calculated
Hardness,
mg/L as
Date CaCO3 Post sump shut-off, low flow
Calculated
Hardness,
mg/L as
Date CRCO3
10/20/98 149 6/25/02 194 12/31/02 352
11/19/98 153 12/31/02 352 1/31/03 305
12/17/98 121 1/31/03 305 2/27/03 222
1/19/99 123 2/27/03 222 7/29/03 258
2/15/99 160 3/26/03 112 7/31/03 146
12/21/00 108 4/29/03 46 9/26/03 165
1/29/01 172 5/22/03 49 10/31/03 138
2/28/01 119 6/23/03 88 11/25/03 112
3/27/01 89 7/29/03 258 12/16/03 123
4/18/01 69 7/31/03 146 1/23/04 123
5/29/01 68 9/26/03 165 2/25/04 93
6/19/01 115 10/31/03 138 7/29/04 86
7/11/01 110 11/25/03 112 8/30/04 76
8/24/01 153 12/16/03 123 9/29/04 90
9/17/01 121 1/23/04 123 7/31/05 221
10/24/01 137 2/25/04 93 8/30/05 214
11/27/01 128 3/30/04 103 11/30/05 138
12/18/01 126 4/28/04 69 12/31/05 103
1/22/02 166 5/31/04 117 2/27/06 123
2/26/02 202 6/29/04 106
3/26/02 115 7/29/04 86
4/24/02 111 8/30/04 76
5/28/02 104 9/29/04 90
3/22/05 93
5/31/05 62
6/22/05 73
7/31/05 221
8/30/05 214
11/30/05 138
12/31/05 103
2/27/06 123
3/29/07 72
Average: 127 Average: 133 Average:
163
4109C.100419 Whetstone Associates