PERMFILE115285

• Permit No: M2004067
• IBM Index Class Name: Permit File
• Doc Date: 7/13/2005
• Doc Name: request for assistance on radiation monitoring
• From: dmg
• To: Philip Egidi CDPHE
• Media Type: D
• Archive: No

DIVISION OF MINERALS AND GEOLOGY
Department of Natural Resources
7313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
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STATE OF CC)LORADO
COLORADO
DIVISION O F
MINERALS
GEOLOGY
0.ECLAMATION•MININO
$AFETY•SCIENCE
Bill Owens

l Govemar
Ju
y 13, 2~~5 Russell George
Executive Director
To: ~ Philip Egidi, CDPHE-HMWMD Radiation Management Program Ronald W. Gnany
Roland Hea, CDPHE-APCD Stationary Sources Program Division Director
Christopher Gates, CDPHE-WQCD Water Quality Protection Secti
o
n
~ Natural Resource Trustee
r
_
.
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From: / Bruce Humphries, DMG, Minerals Program Supervisor `~~ V
RE: Request for assistance on radiation monitoring: Clear Creek District Water Providers, LLC, MMRR
Quarry application; File No. M-2004-067 /
The Division of Minerals and Geology requests assistance from the CDPHE-HMWMD Radiation Management
Program, the CDPHE Air Pollution Control Division, and the CDPHE-WQCD Water Quality Protection Section to
determine how to most practically sample and monitor for potential off-site contamination of radioactive materials
that might become airborne by blasting during open pit mining at a proposed quarry site in Gilpin County. We
would like advice on pre-mining sampling and analysis, advice on how radioactivity levels in blast holes or blast
hole cuttings might be measured prior to blasting to initiate secondary protection measures, and advice on protocols
for water monitoring to ensure protection of surface and groundwater resources.
A mining operator has proposed to quarry from the Precambrian Idaho Springs formation approximately 5 miles
south of Blackhawk, immediately north of Highway 119. The company proposes to excavate quarried rock from
approximately 10-15 acres; the quany area could be increased in future years through amendments to the permit.
Bedrock locally near the proposed mine hosts several mapped uranium occurrences. From the standpoint of
exploration geology, the area has a greater than average potential to house high-grade uranium in veins or
disseminations over a limited area. While no uranium or thorium deposits have been found at the surface in the
proposed quarry area, there is permissive reason to project a possibility, albeit limited, for encountering such
deposits below the surface.
Based on published maps and studies, the Division of Minerals and Geology notes that uranium and thorium occurs
in anomalous concentrations in the local area. Uranium minerals and their radioactive products plus thorium would
be the principal sources of radioactivity.
A neighbor has raised the notion that blasting will release dust that would include radioactive mineral particles that
are present within the rock. If such blasted rock included a high concentration of uranium or thorium, the radiation
levels may be equivalently higher. Potential consequences to human (or animal) receptors downwind from the
blasting that might ingest dust from radioactive minerals are of concern.
Partly at DMG's urging, the operator has proposed to sample drill cuttings from development blast holes for
"uranium." However, we believe that the proposal to sample for uranium might be revised to sample or monitor for
radioactivity.
In addition, objectors have raised concerns for protection of water quality in North Clear Creek from offsite
Office of Office of Colorado
Mined Land Rxlamation Active and Inactive Mines Geological Survey