2020-03-24_PERMIT FILE - C1981019A ‎(2)‎

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 3/24/2020
• Type & Sequence: TR135
• Section_Exhibit Name: Rule 2 Permits -ST
• Media Type: D
• Archive: Yes

RULE 2 PERMITS
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The possible alluvial valley floors near the mine impact areas will incur no adverse impact due to mining
by Colowyo. Surface water pollution will be controlled by sedimentation ponds, sediment control
measures, proper mining and reclamation techniques, and frequent monitoring of discharge water quantity
and quality. The hydrologic consequences of mining will not result in disruption of the essential
hydrologic functions due to the beneficial effects of water treatment and flood control provided by the
sedimentation ponds.
Additional Information
The following excerpt taken from an October 8, 1981 letter from Colowyo to the Division expands further
on the alluvium/colluvium issue in the Taylor Creek drainage.
"In the original permit application submittal, Colowyo had described the soils in the
Taylor Creek Drainage (Map 1013) as Quaternary Alluvium. The description was derived
from a U. S. Department of Agriculture Service Soils Classification Survey at the series
level which identified the Taylor Drainage soil as a (stratified alluvium)."
"On the basis of a September 18, 1981 field reconnaissance by Colowyo personnel
together with Dave Craig and Brian Munson of the CMLRD staff, it was agreed that the
SCS classification of Taylor Creek as an area of stratified alluvium was and is erroneous
particularly as geomorphic criteria required to describe an AVF are absent. As a
consequence, the designation of the Taylor Creek Drainage as quaternary alluvium on
Map 10B, Regional Hydrology has been deleted. This area should be mapped as
colluvium.
"Other examination of the area on September 18, 1981 further confirmed a colluvial
classification, in that some unsuccessful irrigation in the area is presumed to have
occurred, and such irrigation was practiced on the colluvial slopes adjacent to the bottom
of the drainage. No irrigation ditches, however, are extant, and it is apparent that no
subirrigation occurs in the area.
"Additionally, insufficient water flows in the Taylor drainage to sustain any flood
irrigation. Irrigation apparently began from a ditch known as the Mary C. ditch in 1913
on an undetermined acreage, but was certainly less than 25 acres. The state Division of
Water Resources records date back to 1960, and they have no record that this ditch has
been used since that time. Years ago small isolated areas such as this could be irrigated
economically, and were important to 160 acre size homesteads.
"However, in recent years with larger farms and ranches, larger equipment, and increased
labor costs, small isolated areas such as this are seldom irrigated. This is especially the
case when the water source is from an ephemeral drainage such as Taylor Creek, and
runoff is mostly a function of snow melt and large precipitation events, and varies largely
from year to year.
"The revised Map 1013 will be submitted when all of the map revisions have been
completed. Map 10 will also be revised to show that the area of quaternary alluvium
extends to the confluence of Taylor and Wilson Creeks from the north. The labeling of
the gauging stations at the confluence of Taylor and Wilson Creeks will also be corrected
on the revised Map 1013".
South Taylor/Lower Wilson — Rule 2, Page 90 Revision Date: 4/7/17
Revision No.: RN -07