2017-09-29_PERMIT FILE - M1994117

• Permit No: M1994117
• IBM Index Class Name: PERMIT FILE
• Doc Date: 9/29/2017
• Doc Name Note: Potential Violation
• Doc Name: Comment
• From: Michael S. Thomas, P.E.
• To: DRMS
• Email Name: AME
• Media Type: D
• Archive: No

Transportation Department
2525 13th Street, Suite 203 • Boulder, Colorado 80304 • Tel [phone] Fax [phone]
September 25, 2017 pF—Cov
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Amy Eschberger, Environmental Protection Specialist
Colorado Division of Reclamation, Mining and Safety pMS�pNOF�F`" 44 1
1313 Sherman St., Room 215 ��NINGANvSi�
Denver, CO 80203
RE:GOLD HILL MILL SITE—POTENTIAL VIOLATION HEARING ON SEPTEMBER 27, 2017
Ms. Eschberger,
I am the Boulder County Engineer and,on behalf of the Boulder County Transportation Department,
I have investigated Sunshine Canyon Drive (aka Horsefel),which is a Boulder County road, in the
area of a collapse of an existing and historic mine adit coming from the Gold Hill mine.The support
embankment for Sunshine Canyon Drive has experienced recent degradation due to the collapse of
the Gold Hill mine's adit tunnel.The degradation is evidenced by severe subsidence of material and
the erosion of edge of the hillside supporting the road toward the edge of the traveled way.
Photographs 1-4 in in DRMS's inspection report of August 1, 2017 depict this situation accurately.
Type I traffic control devices (vertical traffic control panels)were placed in late spring as the
conditions continued to deteriorate in an effort to maintain the safety of the travelling public.
The Transportation Department has been very concerned about the safety along the north edge of
the road in this collapse area as soon as we were made aware of it and,while the subsidence has
not progressed at a significant rate, it is still of extreme concern that it may progress further,
partially inhibiting travel along the roadway.This would have significant effects on daily travel,
ongoing maintenance,and emergency access on the road, a vital link between Boulder and Gold Hill,
especially with a flood recovery project beginning soon on Gold Run Road (south of Gold Hill)as well
as the onset of winter weather. Continued soil erosion as a result of rain or snow melt would
continue to degrade the edge of the road,further exacerbating the reduction of safety at this
location.
As background,the Transportation Department has had recent historic dealings with the agents of
this mining site,specifically Mark Steen and Lewis Perkins,who I understand to be owner and
operator, respectively.These interactions are summarized below:
May 24,2017—Mike Thomas and Joshua Trickey from Transportation Department met with Lewis
Perkins about guardrail removal for access to perform work on the adit; Mr. Perkins mentioned
sloughing of the hillside over the adit collapse area; Mr. Perkins was also concerned about additional
sloughing due to recent rainfall,stating that moisture had caused concern on his part;the
Transportation Department agreed to monitor but wanted to see what would happen over time
June 21,2017—Mike Thomas and John Holste from Transportation Department looked at the site to
determine further progression of sloughing; noted Type I traffic control devices were in place as a
Cindy Domenico County Commissioner Deb Gardner County Commissioner Elise Jones County Commissioner
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