GENERAL32022

• Permit No: M1983194
• IBM Index Class Name: General Documents
• Doc Name: COVER SHEET-2 PUBLIC COMMENTS ON DRAFT EIS & RESPONSES TO COMMENTS
• Media Type: D
• Archive: No

2. RESPONSES TO PUBLIC COMMENTS

(3) Joinu and dissolution features are examples of
secondary porosity; therefore, no change is necessary.
Response No. 61. This data was submitted to BLM on
May 1, 1984, from Cliffs Engineering, Inc. These data are
from analytical resulu of water sarnples obtained during
drilling of production well no. 1 and from the monitoring
well at the bulk sample site.
Response No. 63. Commenu noted. The paragraph you
refer to was revised in the Water Resources rewrite to provide
clarity, although it may be noted that if roof collapse did
occur, brines would not immedialeny separate or stratify
due to density differences (or some period after structure
stabilvation.
Response No. 64. No change necessary. This action
would cause a significant impact and would notjust slightly
change natural conditions.
Response No. 65. This sentence is describing navel time
under natural conditions Gom the well field to the White
River as estimated from Section 31.2 in the draft E[S,
Groundwater, Site Specific, last paragraph (estimated Oow
of the: lower aquifer is about 90 feet per year).
Response No. 66. No change necessary. The text is
describing remedial actions taken, if and when, the
monitoring systems detect movement: from the well field
or if dissolved solid levels increase.
Response No. 67. No change necessary. Comment does
not add to the statement in the text. It is difficult to distinguish
between a low probability and a very low probability when
not using actual numbers or ranges.
Response No. 68. These figures have been revised due
to a change in pumping rates and hydrologic assumptions.
Current figures compare average maxinnum depletion values
(e.g., 0.06 cfs for 125,000 TPY Alternative) with average
monthly discharge records from the Yellow Creek U.S.
Geological Survey (USGS) station (or water years 1974
to 1982.
Response No. 69. Referral to a recharge rate of 20 and
50 years was incorrect and has been deleted from the text.
The groundwater model, run by Wright Water Engineers,
did not calculate the recovery rate for the aquifer or streams
affected by the pumpage of water on tract. Therefore,
estimated recharge rates and times were not obtainable.
Response No. 70. No change necessary. Changing
"persist for the foreseeable future" to "tlhe wnditions would
stabilize after a certain period of time", would not change
the meaning of the text. Numeric valw:s were not derived
for this impact, therefore no change is necessary.
Response No. 71. Yourcommentpeirtainstoinformation
contained within the Biological Assessment prepared by
BLM in fulfillment of Section 7 of the ]Endangered Species
Act. This document appears in the draft EiS as reference
material and is not subject to revision in the final EIS.
However, BLM must inform the U.S. Fish and Wildlife
Service (USFWS) Endangered Species Office of any
deviations in project design or operation, or newly acquired
information relevant to threatened or endangered species
impact evaluation. Since BLM has refined the water resources
analysis, USFWS will be informed of such changes tbrough
an amendment to the Biological Assessment.
Response No. 71. Based on USGS remrds for water
years 1974 to 1982, Yellow Creek generally maintains Flow
throughout the year. To the best of our knowledge, the
lower 10 miles of Yellow Creek has maintained continuous
Bow from October 1973 to present, except for consecutive
days io September 1978 (6), December 1978 (17), January
1979 (14), and February 1979 (5).
Response No. 73. We acknowledge this correction and
will notify the USFWS of this change.
Response No. 74. Projected Flow depletions for "dry
years" were based on USGS discharge records represented
by the drought and recharge recovery years of 1977 and
1978 when abnormal low Bow patterns were evident for
Yellow Creek.
Response No. 75. BLM would like to expand in depth
on head differences and the relationship of recharge and
discharge areas in the EIS, but this document is not a technical
report. Therefore, we present only a brief overview of
consolidated data and findings.
Response No. 76. Injection pressures will only be
sufficient to overcome the natural piezometric head and eject
solupon from the production well. For further clarification,
please refer to the drag EIS, Sections 4.2.2, Rock Quality
and 4.3, Mineral Resources; and the TEXT CHANGES
section in this document (Water Resources rewrite) for
proposed subsidence impacts from mining alternatives.
Response No. 77. The dissolution is not necessarily
proportional to the areal extent, but for a general comparison
i[ shows that the area affected a minute relative to the
entire basin.
For clarity on the significance of groundwater impacu,
please refer to the TEXT CHANGES section for pages 4-
8 through 4-13 (Water Resources, Environmental
Consequences).
Response No. 78. No change necessary. Wright Water
Engineers contends that the upper and lower aquifers in
the area of the production well field are in direct
communication with one another, due to low head
differences.
Well completion reports indicate that the upper and lower
aquifer were properly isolated when this data was collected.
However, the reported head differences alone do not
substantiate increased communication between the aquifers.
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