GENERAL41505

• Permit No: C1981034
• IBM Index Class Name: General Documents
• Doc Date: 5/1/1984
• Doc Name: PROPOSED DECISION AND FINDINGS OF COMPLIANCE
• Permit Index Doc Type: FINDINGS
• Media Type: D
• Archive: No

V. Surface Water Hvdroloav - Rules 2.
The surface water hydrology Information, sediment control, and protection of
the hydrologic balance sections of the application have been reviewed by the
Division. Surface water information can be found in Volume 1, Volume 8 and
Volume 9 of the application. Additional hydrologic monitoring data was
submitted in May, 1983. Volume 8 (a September, 1982 addendum) addresses a
number of concerns expressed by the Division during the review with regard to
potential impacts of the operation on the surface water regime. Volume 9
(November, 1982) contains post-mining drainage profiles and cross sections of
the disturbed area at Red Canyon. Drainage and sediment control text, plans
and calculations are presented on pages 96a through 108 of Volume 2.
For a description of the surface water hydrology of the mine area (including
baseline data) and a discussion of the impacts of mining on surface water,
please refer to the Surface Water Description and Probable Hydrologic
Consequences - Surface Water portion of Section IX - Probable Hydrologic
Consequences and Cumulative Impact Assessment of this document. Sediment and
drainage control and stream channel reconstruction are discussed below.
Sediment and drainage control at Red Canyon is currently accomplished by a
system of diversion ditches above the disturbed area and a number of
collection ditches and culverts within the disturbed area (see map
2.05.3(4)-2). Disturbed runoff and water pumped from the mine is routed to an
existing sediment pond. The existing pond will be eliminated by construction
of the proposed Red Canyon No. 2 portal bench. Prior to Red Canyon No. 2
development work, a new sediment pond will be constructed farther down the
draw, and will retain disturbed runoff from existing and proposed disturbed
areas at the mine. The existing sediment control system was reviewed and
approved under the requirements of the interim program.
The applicant originally anticipated that "D" seam development and
construction of the proposed diversion system and sedimentation pond would
begin immediately upon permit issuance. As a result, designs and design
calculations for the existing structures were not included in the
application. Subsequently, the applicant has indicated that "D" seam
development and associated sediment control will not be initiated for an
undetermined period of time. A pond certification report of August 30, 1983
indicated that the actual sediment and water storage volumes are somewhat less
than designed. In addition, it has been determined that the pond as
originally designed, was not sized to store mine water in addition to the
design storm runoff. The following stipulation is therefore necessary, in
order to document that the existing sediment control system is in compliance
with permanent program requirements.
Stipulation No
WITHIN 30 DAYS OF ISSUANCE OF THE PROPOSED DECISION, THE PERMITTEE WILL
SUBMIT POND SIZING CALCULATIONS FOR INCORPORATION INTO THE PERMIT
APPLICATION. STORAGE CAPACITY FOR SEDIMENT AND WATER PUMPED FROM THE
MINE MUST BE ADDRESSED. IF THE POND IS DETERMINED TO BE NOT IN
COMPLIANCE WITH THE REGULATIONS, IT WILL BE UPGRADED AS NECESSARY WITHIN
3 MONTHS OF PERMIT ISSUANCE, AND PRIOR TO RESUMPTION OF ACTIVE MINING
STATUS AT RED CANYON.
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