1995-06-27_REVISION - M1988112

• Permit No: M1988112
• IBM Index Class Name: Revision
• Doc Date: 6/27/1995
• Doc Name: FAX COVER
• From: DMG
• To: BMRI
• Type & Sequence: AM1
• Media Type: D
• Archive: No

l • •
~~ BATTLE MOUNTAIN RESOURCES, SAN LUIS PROJECT
CMLRD ADEQUACY LETTER RESPONSES
Page 17 of 28
26. Please provide a sliding wedge stability ana]ysis for the main
embankment at Phase 2, Raise 1 and Phase 2, Raise 2.
RESPONSE: The sliding wedge stability analysis for the main emb ankment is
provided on the revised Figure D.6-9, Sliding Medge Stability
Summary.
27. Please revise the stability analysis summary in Figure D.6-12 to
include the VLDPf instead of the material type 1 as foundation
material.
RESPONSE: Figure D.6-12 has
Material Type 1 been revised to include the VLDPE
as foundation material. The revised instead of
figure is
included here.
28. Please provide a stability analysis of Waste Rock Disposal Area D,
similar to those provided for the other waste rock facilities in the
approved application.
RESPONSE: The stability analysis for Waste Rock Disposal Area D is provided
in Figure D.3-2. This analysis did not include an analysis of the
single bench static and pseudostatic factors of safety. A revised
'~ Figure D.3-2 is provided with this submittal.
29. Please describe what methods will be used to validate the assumption
that unsaturated conditions will be maintained within the embankment
fill throughout the )ife of the facility. Piezometers should be
placed within the embankment, and within the tails adjacent to the
embankment inslope to verify the design assumptions.

RESPONSE: A series of pneumatic piezometers will be placed beneath the
embankment, at the upstream toe of the embankment and within the
beach sands deposited on the upstream slope of the embankment.
30. The model assumes 50% of the tailings disposal area is under
deposition at any point in time and thus 50% of the area will be
evaporating. How many days will an area of tailings be dry and
subject to wind erasion? What would be the maximum extent (acres)
of area with moisture conditions conducive to wind erosion and
resultant dust generation? What measures, aside from residual
moisture, wi)1 be used for dust control?
RESPONSE: Once the area of tailings approaches desiccation and begins to dry
at the surface, this is an indication that the thin layer deposition
concept is working properly and that the area is ready for the next
thin layer to be deposited. Dust generation at the facility will be
controlled through the active management of the thin layer deposition
techniques. As an area dries out, the spigots will be reopened and
more slurry deposited, preventing dust generation.