GENERAL31233

• Permit No: C1980007
• IBM Index Class Name: General Documents
• Doc Date: 10/10/1986
• Doc Name: Proposed Decision & Findings of Compliance for RN1
• Permit Index Doc Type: Findings
• Media Type: D
• Archive: No

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use, only about 1% of the lowest flow on record would be consumed. The
information provided above demonstrates that there is no risk of
material damage to the quantity and quality of water supplying the AVF
identified on the North Fork of the Gunnison River.
Mining activities at the Mt. Gunnison Mine will not affect the quantity
or quality of water in the North Fork or Sylvester Gulch. The coal seam
to be mined lies a significant distance above the North Fork and is not
considered to be an aquifer. Surface facilities have been designed and
located to prevent contamination of the river. The applicant has met
the requirements of Rules 2.06.6 and 2.06.8.
Alluvial Valley Floors - Findings (North Fork and Sylvester Gulch)
"5-Year Permit Area"
Based on the above information, the Division makes the following
findings:
1. The surface coal mining operations would not interrupt,
discontinue, or preclude farming on an alluvial valley floor (Rule
2.06.8(5)).
Although underground mining would occur in areas adjacent to the
alluvial valley floor, all surface disturbances are located more
than a mile upstream from the alluvial valley floor. The alluvial
valley floor will not be undermined by the operations, nor will it
be significantly affected by surface and ground water impacts from
the surface operations.
2. The surface coal mining operations would not materially damage the
quantity and quality of water in surface and underground water
systems that supply those alluvial valley floors or portions of
alluvial valley floors (Rule 2.06.8(5)).
All of the surface flow from the permit area drains to the North
Fork of the Gunnison. The applicant has monitored the largest two
drainages crossing the permit area. During this period, Lone Pine
Gulch has experienced no flow. Sylvester Gulch has experienced
ephemeral stream flow. The record yield of 208 acre -ft/yr, in
1978 is less than 1% of the mean annual flow in the North Fork of
the Gunnison River. Surface flow supplied to the alluvial valley
floor along the North Fork comes primarily from areas upstream from
the permit area and this flow is regulated by Paonia Reservoir
which is located approximately 6 miles upstream of the alluvial
valley floor. Mining operations require approximately 150 acre-ft.
of fresh water per year for sanitary and drinking water. This
water is withdrawn from the North Fork during spring runoff when
water rights are available and used throughout the year. The
wastewater is then treated and returned to the hydrologic system
through periodic discharges from the waste water treatment plant.
This results in negligible loss to the system.
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