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 E49-16
Impacts to Receiving Streams -Minimum Required Stream Flow at Maximum Site 115 Discharge, 1999
Meeting Sulfate Standard on Trout Creek below Fish Creek
a
b
'17
t'~
m
W
0
N
O
O
O
Mine discharges (max. loading) Flow ~ Flow TDS ; Conduct. ~ Sulfate ~ Year
(see Case 1) cfs 1 gpm f mg/L ~umhos/cm1 mg/L 1
109 0.76; 3421 2900; 39001 1600; 1999
115 2.671 12001 61001 73001 33001 1999
Mean Flow Dry Year Flow
Estimated Baseline Flow TDS I Conduct. ~ Sulfate Flow ~ TDS ;Conduct. ; Sulfate
cfs ? mg/L ;umhos/cm; mglL cfs ! mg/L ;umhoslcm; mglL
Trout Creek, above Fish Creek 46.41 3831 511 I 158 87.61 4121 5491 174
Fish Creek above confl. W/Trout 26.0; 441; 588; 172 36.6! 456; 608j 181
Trout Creek below Fish Creek 1999 72.4 4041
1 5381
I 163 124.2

1 4251 5671
I
1 176

Predicted Values I 1 1 ~ 1
1999 1 1 I
Trout Creek, above Fish Creek 47.2; 424; 565; 181 88.3; 4331 578; 186
Fish Creek above confl. W/ Trout Creek 28.71 9691 12141 464 39.31 8401 10631 393
_
Trout Creek below Fish Creek 75.81 6301 811; 288 127.7; 5591 7281 250
Mine Discharge Data Flow & 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.
Sulfate for 109 from 3130/99 analysis of 6 Right inflow, lower values prorated from TDS value
Sulfate for 115 from 2/8/99 analysis, lower values prorated from TDS value
Baseline Water quality data taken Low Flow Data from Exhibit 32
Trout Creek below Fish Creek is value being calculated
Other segment flows set to be same ration of flows in Low Flow baseline conditions in Exhibit 32
Predicted values calculated using mass balance equation shown in text
TR 99-72
Table E49-16
5/3/99