2018-01-02_REPORT - C2010089

• Permit No: C2010089
• IBM Index Class Name: Report
• Doc Date: 1/2/2018
• Doc Name: Annual Hydrology Report
• From: Tri-State Generation and Transmission Association, Inc
• To: DRMS
• Annual Report Year: 2017
• Permit Index Doc Type: Hydrology Report
• Email Name: BFB
• Email Name: DIH
• Media Type: D
• Archive: No

Spoil Springs — Data for sites SS -1 (toe of backfill NH1 mine) and SS -2 (up gradient of SS -1)
have been complied and are shown on the summary tables below and graphically. Summary
tables for indicator parameters are provide below for each site and include data from 2008 to the
end of September of 2017 if available.
't `j i.xory.,+�oh,,=�r,•�i5?'�Y;`� r�'��"F��t_' .t'.. -_"�,r:;n. ;�A. ,.<'v' �t•8+,� ..�i` z' p�91;'�"�s;t i „�,``-;w ty�`:z�'
»k,. .+, ,iL ;:'�II.C' :.{moi.-„d,,.�:.,-,.• �'�.- , 'Y. :.?_�41.-..E.. _.....c`�'.r +�¢ - .,. , a , t»ok. .:�;�','-,. ,� .-.�Y n,-.= x
Me"t..�,�i
an ;^ d Range ' ` Min. ._ Min at
Lob PH'
7.9
0.1
0.5
9.2
7.7
; 11110 '
5/22/14
Lab Cc A (nT!�osian)
2,922
609
2,916
3,430
514
2/1 AS
11/25/13
TDS (mg/1)
2,708
656
2.970
3,280,
310
111/7/14
11/25/13
Sulfate (mg/1)
1,726
453
2,009
2,150
141
11117/14
11/25/13
Calcium (mg4)
491
109
511
586
75
11/17/14
11/25/13
Iron (tot rec ug/1)
1,925
2,658
10,000
10,400
400
11/27/14
8/19/14
Magnesium (mg/1)
204
21
245
259
14
2/12/15
11/25/13
Sodium (mg/1)
38
10
46
53
7
5/16/17
11/25/13
SS -2
Parameter Mean Std Range Max. Min. Max at Min at
dev
Lab pH - - - - - - -
Lab Cond. (umhos/cm) - - - - - - -
TDS (mg/1) - - - - - - -
Sulfate (mg/1) - - - - - - -
Calcium (mg/1) - - - - - - -
Iron (tot rec ug/1) - - - - - - -
Magnesium (mg/1)
Sodium (mg/1)
A review of the water year data no minimums or maximums occurred at either spring. SS -2 was
did not flow for the entire water year.
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