2018-10-19_PERMIT FILE - M2016054 ‎(6)‎

• Permit No: M2016054
• IBM Index Class Name: PERMIT FILE
• Doc Date: 10/19/2018
• Doc Name: Adequacy Review Response
• From: Blue Earth Solutions
• To: DRMS
• Email Name: AME
• Email Name: MAC
• Media Type: D
• Archive: No

blue earth
SOLUTIONS
October 16, 2018
Colorado Department of Natural Resources RECEIVED
Division of Reclamation, Mining and Safety OCT ,� 9
Attn: Ms. Amy Eschberger 2018
1313 Sherman Street; Room 215 OMSION OF RECLAMgT"
Denver Colorado, 80203 MINING MD&VM
RE: Response to Adequacy Review Comments dated September 28,2018
Irwin/Thomas Mine, Permit No. M-2016-054,Aggregate Industries—WCR, Inc.
Dear Ms. Eschberger:
The following discussion and attachments are submitted on behalf of our client, Aggregate
Industries—WCR, Inc., in response to the Adequacy Review comments prepared by the Division
of Reclamation, Mining and Safety dated September 28, 2018 for the Irwin/Thomas Mine 112
Construction Materials Reclamation Permit application. The information and discussion below
address each comment as it was presented by the Division:
Proof of posting responses to the Adequacy Review comments dated September 28, 2018
with the Boulder County Clerk and Recorder is attached.
6.4.7 Exhibit G— Water Information
1. The applicant commits to incorporating all of the Flood Impact and Mitigation Evaluation
Report (Blue Earth Solutions, LLC, July 2018) recommendations into the Irwin/Thomas
Mine mining and reclamation plans. Mining Cell IA in MA1 (see revised Exhibit C-4,
Pre-Mining Plan Map) shall be mined and backfilled prior to other MA1 mining within the
St. Vrain Creek jurisdictional 100-year floodplain. Mining and backfilling in Cell I shall
occur during the non-flood prone season; October through April. Similarly, in MA3 and
MA4 the first 200 feet of the mining cells closest to St. Vrain Creek shall be mined and
backfilled prior to other mining in the cells. This initial mining and backfilling shall also
occur during the non-flood prone season; October through April.
2. A revised Exhibit C-5, Water Resources Map, is attached (Attachment A) and includes the
non jurisdictional 100-year floodplain boundary developed for the City of Longmont
Resilient St. Vrain Project. Revised Exhibits C-4, Pre-Mining Plan Map, and F-1 through
F-4, Reclamation Plan Map, are also attached (Attachment A). The revised plan maps
illustrate the changes made in response to the Flood Impact and Mitigation Report
recommendations including the mining sequencing to establish backfill setbacks from
St. Vrain Creek.
In the Flood Impact and Mitigation Report, some mining and backfilling setback distances
are referenced from the St. Vrain Creek top of bank. Since this reference point may be
difficult to identify in the field, the City of Longmont pedestrian path has been called out on
Blue Earth Solutions, LLC P.O.Box 2427 Fort Collins,CO 80522 # [phone]