HYDRO27678

• Permit No: M1974015
• IBM Index Class Name: Hydrology
• Doc Name: AN ANALYSIS OF POSSIBLE GROUNDWATER & SURFACE WATER IMPACTS RESULTING FROM LYONS ROCKIN WP GRAVEL P
• Media Type: D
• Archive: No

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Table S
Western Mobile, Inc.
Average Impact on 5[reamflow
Amended Application Only
Historic Cotditions Future Conditions
Discharge from Recharge from Discharge from Recharge from
Depth to Impact of Mining on
Date Alluvium to Stream to Alluvium to Svearn to
Water Surface Flow in Stream
Stream Alluvium Stream Alluvium
(1} (2) (3) (~) (5) (6)
(feet) (acre-feet) (acre-feet) (acre-feet) (acre-feet) (acre-feet) (cfs)
15-Dec 5.78
7.1 0.6 -6.5 -0.11
IS-Jan 5.88
4.8 0.4 -4.4 -0.07
IS-Feb 5.95
0.9 O.l 0.9 0.02
15-Mar 5.94
36.8 2.9 33.9 0.55
15-Apr 5.42
94.3 7.4 86.9 1.46
I S-May 4.11
20.6 1.6 -19.0 _0.31
15-Jun 4.40
18.2 L4 16.8 0.28
15-Jul 4.14
8.1 0.6 7.4 O.12
15-Aug 4.03
58.2 4.6 -53.60 _O,g7
15-Sep 4.84
23.6 l.9 -21.7 -0.36
15-Oct 5.17
31.2 2.5 -28.7 -0.47
15•Nov 5.60
13.1 I.0 -12.0 -0.20
15-Dec 5.78
Total 158.4 158,4 12.5 12.5 0.0
' Notes: Mined Area : 477.92 acres
Pond Area : 5.64 acres
' Specific Yield O.IS
(1) Depth to water surface is determined Gom the average depths of all piezometers for the study period, Gcm Figure ?.
(2) Historic dischazge from alluvium to stream equals the change in the depth to the water table Gom the prvious month times the
' nursed area times the specific yield of the aquifer, during periods when the water table historically drop:.
(3) Historic recharge Gom stream to alluvium equals the change in the depth to the water [able Gom the previous month times the
mined area times the specific yield of the aquifer, during periods when the water table historically rises
' (4) Fu[we discharge Gom alluvium to stream equals the change in the depth to the water (able Gom the previous month tunes Ute
unlined pond azea, as the specific yield of the ponds is 1.0, during periods when the water table historic illy drops.
(5) Historic recharge Gom stream to alluvimu equals the change in the depth to the water table from the previous month times the
unlined pond area, as the specific yield of Ure ponds is L0, during periods when the water table historically rises.
(6) The impacts of the cturent application ou Ilmv in sVeam equals the change in the storage due to the mining operation plus the
addition of the unlined pits. Negative numbers represent a decrease in streamlloa• due to a decrease in discharge from the
' alluvium to the streams. Positive numbers represent an increase in streatn0ows due to a decrease in recharge to the alluvium.
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