PERMFILE67692

• Permit No: C1982056
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: EXHIBIT 49 PHC Modification Support Tables
• Media Type: D
• Archive: No

•,
Table E49-21
Impacts to Receiving Streams, SAR -Case 3
a
b
b
'~7
°e'
tf7
b
Mine discharges (max. loading) Flow TDS Conduct. ~ Sodium : Calcium Magnes. SAR i Year
cfs mg/L lumhos/cm1 mg/L mg/L mg/L i
109 max. combined 0.09; 3000; 4000; 834; 230; 196; 9.8; 1999
115 max combined 8 individual 1.34; 6100; 7300; 1620; 258; 139; 20.2; 1999
109 max. individual 0.58; 23001 3100; 639; 176; 1501 8.6; 2014
115 value to use w/109 max. 0.90; 2900T - 3 OB 0 770 j 123; 66j 13 9 2014
M ean Flow Dry Year Flow
Estimated Baseline (Exhibit 32) Flow ~ Sodium ~ Calcium ~ Magnes.. SAR Flow ] Sodium ~ Calcium ~ Magnes.. SAR
cts mg/L mglL mg/L cts mg/L mg/L mg/L
Trout Creek, above Fish Creek 46.4; 20.11 58.3; 28.81 0.5 16.5; 7; 37; 16; 0.2
Fish Creek above confl. W/ Trout 26.01 44.51 60.8; 37.7; 1.1 6.91 661 901 341 1.5
Trout Creek below Fish Creek 72.4; 28.9; 59.2; 32.0; 0.8 23.4; 24.3; 52.4; 21.2; 0.7
Predicted Values
Combined 109 + 115 Load Maximum
Trout Creek, above Fish Creek 46.5; 21.7; 58.7; 29.2; 0.6 16.6; 11.7; 38.1; 17.0; 0.4
Fish Creek above confl. W/ Trout Creek 27.31 121.5; 70.4; 42.7; 2.8 8.2; 319.7; 117.4; 51.1;
' 6.2
Trout Creek below Fish Creek 73.81 58.71 63.01 34.21 1.4 24.8; 113.41 64.31 1
28.3 2.3
109 at individual Load Maximum
Trout Creek, above Fish Creek 47.0; 27.8; 59.8; 30.3; 0.7 17.1; 28.6; 41.8; 20.6; 0.9
Fish Creek above confl. W! Trout Creek 26.91 68.81 62:91 38.71 1.7 8.21 140.11 88.81 35.71 3.2
Trout Creek below Fish Creek 73.8; 42.8! 61.0; 33.4! 1.1 24.9; 65.7; 57.9; 25.9! 1.8
Mine Discharge Data Flow 8 conductivity from estimated future water balance. TDS calculated from conductivity: TDS = 0.75' cond.
except for conductivities greater than 5000 umhos/cm TDS = 0.84' cond.
Cations for 109 from 3130/99 analysis of 6 Right inflow, lower values prorated from TDS value
Cations for 115 from 2/8/99 analysis, lower values prorated from TDS value
Baseline data Mean and low flow rates taken from Exhibit 32
Low Flow water cations from Table 63
Mean flow cations for Trout Creek upstream & Fish Creek are mean values of pre-1984 data for sites 69 and 1003
Mean flow cations for Trout Creek downstream are calculated from Trout Creek upstream and Fish Creek values
-~T Predicted values calculated using mass balance equation shown in text (2.05.6(3)(b)(iii) Probable Hydrologic Consequences, Surface
~ Water Systems, Impacts of Mine Water Discharge)
o Example: Fish Creek above confl. W/Trout Creek, 109+115 max =
cn [[0.67(Flow~)•258(Ca,)J+[26.0(Flowz)'60.8(Ca=)]]126.7(FlowroJ = 65.7
o SAR = (Na • 0.0435) /{ [(Ca' 0.0499) +(Mg' 08226)]^0.5}
0
TR 9332 Table E49-21
11!15/99