Laserfiche WebLink
CMC <br /> Continental Materials Corporation <br /> Transit Mix Concrete Co. 440 S. LaSalle St. Suite 3100 <br /> Chicago IL 60605 <br /> January 3,2016 <br /> Mr.Tim Cazier <br /> Colorado Division of Reclamation, Mining and Safety <br /> 1313 Sherman,Suite 215 <br /> Denver,CO 80203 <br /> Subject: Wash Fines Pond Embankment Technical Revision geotechnical clarification <br /> information for Transit Mix Concrete Company on behalf of Continental Materials <br /> Corporation, Daniels Sand Pit#2 M-1973-007SG <br /> This document is intended to answer questions from Mr.Tim Cazier and Mr.Wally Erickson post Daniels <br /> Pit#2 site inspection on December 7, 2016 and post meeting held in the Department of Reclamation, <br /> Mining, and Safety(DRMS)office on December 19, 2016. <br /> Responses to your comments and questions are provided by Brierley Associates.These refer to the <br /> geotechnical stability of the embankment, operating practices,and dam jurisdiction of the Daniels Sand <br /> Pit#2 Wash Fines Technical Revision. <br /> Pond Jurisdiction <br /> The Colorado Division of Water Resources(CDWR), Dam Safety Branch has deemed the proposed Wash <br /> Fines Pond at Daniels Sand Pit#2 as an "exempt structure under 2-CCR 402-1 Section 17.1.4 based on <br /> the fact that the water impoundment will be completely below existing ground and no low outlet will be <br /> constructed."They have added the proposed structure to their database under DAMID: 100472. See <br /> Appendix A for a copy of the letter from CDRW, Dam Safety Branch. <br /> Embankment Failure Volume Comparison <br /> The maximum height of the Wash Fines to be deposited in the proposed pond will be at the 5,807 foot <br /> elevation, mean sea level (MSL)with the crest of the embankment will be at the 5,810 foot elevation <br /> (MSL).Transit Mix Concrete Company(TMCC) on behalf of Continental Materials Corp. (CMC)commits <br /> to keeping a minimum of three (3)feet of free board below the designed embankment crest elevation. <br /> When assessing volumes that would be present in a failure situation of the proposed embankment, <br /> Brierley Associates evaluated an embankment failure when the pond was at full capacity or an <br /> approximate volume of 452 acre-ft of water and fines. The expected flow of water and fines in the event <br /> of a failure will reach an elevation of 5,797 feet(MSL) or 5 feet above the invert elevation of the <br /> underpass at Academy Blvd. Brierley Associates concludes some material will likely flow through the <br /> underpass at Academy Blvd, however the likely hood of off-site impacts would be insignificant.See <br /> Appendix B: Brierley Associates Geotechnical Evaluation Memorandum for a discussion of this. <br />