2005-02-23_REVISION - M1977208

• Permit No: M1977208
• IBM Index Class Name: Revision
• Doc Date: 2/23/2005
• Doc Name: Addendum/Clarification to January 27 2005 Response to Adequacy
• From: CEMEX Inc
• To: DMG
• Type & Sequence: TR4
• Media Type: D
• Archive: No

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~~c-mix RECEIVE®
Erica Crosby FEB 2 3 Z~~ Febtuary 21, 2005
Environmental Protection Specialist Oivisian of Minerals and Geology
Division of Minerals and Geology Via Certified Mail
1313 Sherman St., ROOM 215 Return Receipt Requested
Denver, Colorado 80203 7004 2890 0003 2049 7779
RE: Addendum /Clarification to January 27, 2005 Response to Adequacy,
Comex, Inc., Lyons Quarry, Permit No. M-1977-208, TR-04.
Dear Ms. Crosby,
This letter clarifies, and in some cases slightly changes, our January 27, 2005 response to
adequacy. The issues are enumerated below:
Monitoring of off-site Dakota Formation Well (i.e. Hall Well)
Cemex has proposed no monitoring of this well based on findings on the geology and
hydrology of the area and the results of the computer modeling. In addition, artesian
conditions in this well (see attached letter report from Richard Henry) further support the
proposal not to monitor this well. Monitoring of this well may be warranted pending data
from the new detection well that will be installed in the coming months.
2. C-pit Water Ouality Monitoring
C-pit will continue to be monitored every 2 weeks until TR-04 is approved, and monthly
thereafter until data from the detection well is available. Following that, C-pit will be
monitored quarterly until there is no ponded water remaining.
Ate- it Water Ouality Monitoring
A-pit will be monitored every 2 weeks until TR-04 is approved, and monthly thereafter until
data from the detection well is available. A-pit monitoring will cease altogether upon
approval of the Division if the detection well is dry or if water quality in the detection well
meets applicable standards and is unaffected by C-pit water quality. Cemex will provide
written data from the detection well (i.e. water quality results or evidence of lack of water)
to the Division within 10 business days of receipt.
4. Water Treatment Plans
The water quality and volume of water remaining in C-pit will be determined in October
2005. Based on these data, a specific water treatment and mitigation plan will be developed
and submitted to the Division as a Technical Revision. Wildlife access mitigation may be
used as an alternative to water treatment. This Technical Revision will be submitted by
November 1, 2005. This plan will be implemented as warranted within 30 days of approval
of the Technical Revision.
Untied States Operations
P.0. Box 529, Lyons, Colorado 80540, USA, Phone: [phone], Fax: [phone]