2023-10-31_REVISION - M1973021 ‎(25)‎

• Permit No: M1973021
• IBM Index Class Name: Revision
• Doc Date: 10/31/2023
• Doc Name Note: Introduction and Table of Contents
• Doc Name: Request for Technical Revision
• From: Holcim - WCR, Inc.
• To: DRMS
• Type & Sequence: TR9
• Media Type: D
• Archive: No

Ninth Technical Revision(TR09)to Permit M-1973-021,Holcim-WCR,Inc.Morrison Quarry
1 Introduction
1 . 1 Purpose and Objectives
The purpose of this document is to support the request to the Colorado Division of Reclamation
Mining and Safety (DRMS) for a Technical Revision JR) to the 112c Reclamation Permit Operations
for Morrison Quarry (File number M-1973-021). The objective of this document is to provide a
narrative and updated Exhibits that explain the requested revisions to the approved Phase III Mining
and Reclamation Plans based on anticipated exposure of groundwater in the South Quarry. Revised
Exhibits include the following:
Exhibit D— Mining Plan
Exhibit E— Reclamation Plan
Exhibit F— Reclamation Plan Map
Exhibit G —Water Information
Exhibit L— Reclamation Costs
Rule 6.5 —Geotechnical Stability Exhibit
Specifically, Holcim requests that the Phase III South Quarry mining plan and reclamation plans,
below elevation (El.) 6,600, be modified to focus mining operations in an area referred to as the
Satellite South Pit. The Satellite South Pit mining will proceed in accordance with the mining plan for
the South Quarry approved in AM07 for benches below El. 6,600. Based on groundwater level
monitoring in and around the South Quarry, groundwater is anticipated to be encountered. This TR
also discusses how groundwater will be managed in the South Quarry once encountered.
Other revisions to the approved reclamation plan include the following:
• Updates to the drainage plan for the South Quarry specifically drainage for the reclaimed
West Wall of the South Quarry;
• Updates to the reclamation plan to remove the South Quarry horizontal drain; and
• Remove groundwater monitoring requirements in the South Quarry based on ongoing efforts
to complete a Substitute Water Supply Plan and well permit for the South Quarry.
1 .2 Background
Morrison Quarry is a hard rock aggregate mine located west of Colorado Highway 8 and
approximately 0.5 miles north of U.S. Highway 285 in Morrison, Colorado. The mine site is located
west of the Dakota hogback along the Colorado Front Range west of Denver. Morrison Quarry
currently consists of four mining cells that are either active or in reclamation stages: the North
Quarry, the Central Quarry, the South Quarry, and the West Quarry. Active mining is limited to the
South Quarry and West Quarry.
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