2011-05-18_PERMIT FILE - C1981012 ‎(2)‎

• Permit No: C1981012
• IBM Index Class Name: Permit File
• Doc Date: 5/18/2011
• Doc Name: PROBABLE HYDROLOGIC CONSEQUENCES OF MINING
• Section_Exhibit Name: Exhibit 08.4 Probable Hydrologic Consequences of Mining on the Allen & Apache Coal Seams
• Media Type: D
• Archive: No

Probable Hydrologic Consequences New Elk Mine 15
East Portal Shaft and monitors potential effects of mining on stream water quality. Data for PRS -1 and
PRS -4 between 2001 and 2008 are summarized Table 8.
Table 8. Water Quality Summary Table for Stations PRS -1 and PRS -4 on Purgatoire River
4.2 Apache Canyon
Apache Canyon is an ephemeral drainage that traverses the permit area in a north easterly direction and is
tributary to the Purgatory River. The canyon drains an area of approximately 7,264 acres and is divided
into Right and Left Forks that join near the eastern edge of the permit area. The canyon is narrowly incised
and contains a thin veneer of alluvium and colluvium along the valley floor. The unconsolidated deposits
have limited lateral extent and are unsaturated for most of the year.
Surface flows in Apache Canyon occur only in response to snowmelt and precipitation in the surrounding
drainage. A flume with continuous recorder (station AFC -1) was established on the main stem of the
drainage approximately 1 mile below the confluence of the Right and Left Forks in 1984 (Plate 3). The
station recorded 20 days of flow over the following year and was discontinued in 1985. Stream flows
occurred in response to localized heavy thunderstorms and snowmelt. All flows were recorded as short
duration spikes on the hydrograph ranging from 0.001 to 51 cfs (WFC, 1985).
Three bedrock springs occur in the Apache Canyon and are shown as springs 12, 13, and 14 on Plate 3.
Springs 12 and 13 originate at contacts between shale and sandstone. Spring 14 originates from the contact
between a coal bed and a shale or sandstone layer. Spring 14 is a developed pond for livestock use. The
4164A.110421 Whetstone Associates
'I'D G6. QfA1 Donn 1 I,< it / ) 1
PRS -1
PRS -4
Parameters
Units
# of
Min
Max
Mean
# of
I
Min
Max
Mean
Samples
Samples
Solution Parameters and Major Ions
pH (Lab)
S.U.
2
8.0
8.2
8.1
2
8.1
8.2
8.2
Hardness
CaCO mg /1
8
129
178
150
8
131
177
153
SAR
S.U.
8
0.2
0.27
0.24
8
0.22
0.31
0.26
TDS @180C
mg/I
8
5
200
141
7
160
200
180
TDS (calculated)
mg /1
5
146
195
174
5
135
197.5
177
TSS
mg /I
6
5
8
6
6
5
12
7
Settleable Solids
mg/I
0
- --
- --
- --
1
5
5
5
Hydroxide
CaCO mg /l
5
2
2
2
6
2
2
2
Carbonate
CaCO mg /1
8
2
2
2
8
2
2
2
Bicarbonate
CaCO mg /1
8
64
143
121
8
77
143
126
Calcium, dissolved
mg /I
8
40.4
57.2
46.7
8
41.7
56.5
47.4
Chloride
mg/1
7
1
5
2
7
1
3
2
Magnesium
mg /1
2
7.2
7.9
7.6
2
7.4
8.7
8.1
Magnesium, dissolved
mg/1
8
6.4
9.4
8.1
8
6.5
10.1
8.4
Potassium, dissolved
mg /I
8
1.1
1.6
1.3
8
1
2
1.3
Sodium, dissolved
mg/l
8
5.3
8
6.8
8
5.9
9.3
7.5
Sulfate
mg/I
1 8
20
50
34
8
23
40
33
Metals
Iron, total
mg/l
8
0.07
0.64
0.32
8
0.12
0.73
0.33
Iron, total rec.
mg/l
8
0.07
0.64
0.28
8
0.11
1.02
0.33
Iron, dissolved
mg/I
8
0.03
0.15
0.06
8
0.03
0.83
0.15
Manganese
mg/I
0
- --
- --
- --
1
0.064
0.064
0.064
Manganese, total
mg /1
8
0.019
0.072
0.044
7
0.022
0.078
0.048
Manganese, dissolved
mg /I
8
0.006
0.036
0.022
8
0.007
0.042
0.024
Lead, dissolved
mg /I
3
0.0001
0.001
0.0007
3
0.0001
0.001
0.0007
Selenium, dissolved
mg/1
2
0.001
0.001
0.001
3
0.001
0.002
0.001
Zinc
mg/I
1 1
5
5
5
1
0.01
0.01
0.01
Field Parameters
Flow
cfs.
18
2.57
326.3
45.7
19
5.5
288
43.8
pH
S.U.
20
7.3
8.8
8.1
21
7.3
8.8
8.1
Specific Conductance
µS /cm
20
193
425
300
21
192
825
348
Temperature
°C
20
1.5
21.6
7.2
21
0.8
23
7.1
4.2 Apache Canyon
Apache Canyon is an ephemeral drainage that traverses the permit area in a north easterly direction and is
tributary to the Purgatory River. The canyon drains an area of approximately 7,264 acres and is divided
into Right and Left Forks that join near the eastern edge of the permit area. The canyon is narrowly incised
and contains a thin veneer of alluvium and colluvium along the valley floor. The unconsolidated deposits
have limited lateral extent and are unsaturated for most of the year.
Surface flows in Apache Canyon occur only in response to snowmelt and precipitation in the surrounding
drainage. A flume with continuous recorder (station AFC -1) was established on the main stem of the
drainage approximately 1 mile below the confluence of the Right and Left Forks in 1984 (Plate 3). The
station recorded 20 days of flow over the following year and was discontinued in 1985. Stream flows
occurred in response to localized heavy thunderstorms and snowmelt. All flows were recorded as short
duration spikes on the hydrograph ranging from 0.001 to 51 cfs (WFC, 1985).
Three bedrock springs occur in the Apache Canyon and are shown as springs 12, 13, and 14 on Plate 3.
Springs 12 and 13 originate at contacts between shale and sandstone. Spring 14 originates from the contact
between a coal bed and a shale or sandstone layer. Spring 14 is a developed pond for livestock use. The
4164A.110421 Whetstone Associates
'I'D G6. QfA1 Donn 1 I,< it / ) 1