2001-06-14_GENERAL DOCUMENTS - C1981014

• Permit No: C1981014
• IBM Index Class Name: General Documents
• Doc Date: 6/14/2001
• Doc Name: Proposed Decision and Findings ‎(RN-3)‎
• From: DMG
• Permit Index Doc Type: Findings
• Email Name: JHB
• Media Type: D
• Archive: No

CONTAINING RECORDS OF WATER DISCHARGED FROM THE MINE, CONSUMED
IN THE MINE AND IMPORTED FOR USE WITHIN THE MINE; AND A
DISCUSSION OF WATER BALANCE WITHIN THE MINE. THE INFLOW STUDY
IS TO BE DONE DURING THE SPRING OF EACH YEAR WITH THE REPORT
SUBMITTED BY JULY 1 .
The language of Stipulation No. 7, pertaining to collection and
reporting of hydrologic monitoring data, has been incorporated
into pages 2 . 05 . 6-52 through 2 . 05 . 6-54 of the permit
application, and is considered satisfied.
These long-term data records are necessary to identify any
pattern of water quality changes . EFCI ' s hydrologic
monitoring plan should be adequate to predict possible
hydrologic impacts and determine if a modification of surface
or underground mining activities, to minimize disturbances to
the prevailing hydrologic balance, is necessary (Rule
4 . 05 . 13 . (1) (b) ) .
The Southfield Mine workings have the potential to deplete the
quantity of groundwater through mine-induced groundwater
flows. The mining operation will induce inflows by dewatering
the coal seam and the associated roof and floor strata as the
mine workings advance. In addition, overlying aquifers could
be dewatered through subsidence-related fractures . Locally
perched groundwater aquifers in strata above the workings may
be dewatered through subsidence cracks or fractures . Thus the
water will drain down through the fractures to the voids
created by the mine.
The greatest potential effect on ground water is for perched
aquifers in the Vermejo and the overlying Raton Formations to
be dewatered by subsidence . Wells that use these perched
aquifers could experience drawdown effects . However, due to
the low hydraulic conductivity of the associated aquifers, the
fact that the aquifers in this area tend to be laterally
discontinuous and the effects of past surface and underground
mining, ground water impacts (both magnitude and extent) are
difficult to predict . The operator is obligated to comply
with Rule 4 . 05 . 15 pertaining to water rights and replacement
if an owner is injured as the result of the operation. The
ground water monitoring plan has been designed to identify
ground water impacts before they extend to water supply wells .
These measures will ensure a better understanding of the
impacts to the ground water system and protection of water
resources in the future.
Southfield Mine Permit Renewal 03
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