2017-03-23_REPORT - M1988112

• Permit No: M1988112
• IBM Index Class Name: REPORT
• Doc Date: 3/23/2017
• Doc Name: Annual Fee/Report/Map
• From: Battle Mountain Resources, Inc.
• To: DRMS
• Annual Report Year: 2017
• Email Name: WHE
• Media Type: D
• Archive: No

July 6. 2016 Miller Geotechnical Consultants,Inc.
1027 W.Horsetooth Rd,Suite 200
Fort Collins, CO 80526
[phone](office)
[phone](mobile)
[e-mail]
Battle Mountain Resources. Inc.
PO Box 310
San Luis. CO 81152-0310
Attn: Mr. Julio Madrid. Site Manager
Re: 2016 Dam Safety inspection Report for San Luis Tailings Dam
Dear Mr. Madrid:
Attached is the 2016 Annual Inspection Report for San Luis Tailings Dam. phis is the third annual dam
safety inspection conducted by Miller (icotechnical Consultants (MGC) for the facility following the
initial (2013) detailed inspections and dam safety analysts ofthe facility performed by MGC' which are
documented in the initial Detailed Inspection Report(MG(' 2014').
The subsequent first annual inspection%%as performed in April 2014. Tvvo maintenance issues were noted
in the April 2014 annual inspection: (1) minor surface erosion was observed in an area repaired in 2013
can the downstream right groin ofthe dam embankment. and (2) re-blocking ol'the sub-drain pipe outfalls
at the toe ofthe dam due to sloughing of earth materials above tite pipes. T`he pipe out falls were cleared
of debris in 2013 but new sloughing had partially re-covered the pipes in the spring of 2014. After the
.April 2014 annual inspection. the right groin area vvas repaired again by re-grading and construction of
contour herms and ditches on the dam face directing runoff into the right groin ditch.
Fhe second annual inspection was completed in January 2015. At that time, the right groin area repair
appeared to be in good condition, but minor erosion rills were observed. Additional erosion protection
was recommended to prevent gullying and erosion in this area. In 2015 the erosion-control measures were
enhanced by adding riprap-fined down-drain channels. and seeding »ith vegetation (see Photos 16-21.
attached). The system appears to he �%orkinl_' quite well, except for some erosion where flow from the
rock-lined down-drains is jumping over the contour berms at the bottom of the rock channels(see Photos
19 and 20). This situation should continue to be monitored and may be improved by minor grading efforts
and shaping ofthe dcnvn-drain channel:to reduce flow velocities into the cross berms. Vegetation appears
to be getting established .utd the erosional stability in this area is anticipated to improve over time as
vegetation matures.
titGC (2014) San t.ws Project Iailing Dam Detailed inspection Report. prepared for Battle Afountain Resources Inc. be
Miller Geotechnical Consultants.Fort Collins.CO,Februan.
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2016 Dam Safety Inspection Report San Luis Tailings Dam