2019-02-26_REVISION - M1996052

• Permit No: M1996052
• IBM Index Class Name: REVISION
• Doc Date: 2/26/2019
• Doc Name: Concurrence Correspondence
• From: LG Everist
• To: DRMS
• Type & Sequence: TR1
• Email Name: ECS
• Media Type: D
• Archive: No

DEERE & AULT
CONS UL-FAN-rS,INC.
MEMORANDUM
TO: Matt Noteboom, L.G. Everist
FROM: Scott Palmer and Roy Spitzer,Deere & Ault Consultants, Inc.
DATE: July 23, 2010
RE: Firestone Site, Slope Liner Design; D&A Job No. CG-0201.011.00
As per our proposal dated May 11, 2010, we provided engineering services for the design of a
slope liner at the Firestone Resource Site located near Firestone in Weld County, Colorado. As
part of these services we reviewed the available project data, developed parameters for design,
and prepared a project manual. Following mining, the aggregate mine may be reclaimed as a
below grade water storage reservoir. The project manual includes select construction documents
for the design consisting of a technical memorandum, technical specifications for the
embankment construction, forms for documenting the construction, and a typical cross-section
for the slope geometry analyzed. The goal of these engineering services is to provide general
guidance in mine reclamation to support permit acquisition, and provide a general plan for
reclamation following mining. These documents do not include a site specific grading plan,
specific cross-sections, stationing, or complete reservoir design.
PURPOSE OF DESIGN
The goals for this engineering project include:
1. Design a compacted soil embankment slope liner section calculated to meet leakage
design standards as set forth by the Colorado "State Engineer Guidelines for Lining
Criteria for Gravel Pits," August 1999.
2. Design of a reclamation slope using site soils, which will meet or exceed the minimum
standards set by the DRMS for reclaimed gravel pits and which are calculated to provide
suitable factors of safety for stability over typical range of reservoir operating conditions.
To accomplish these design goals, the analysis of the soil embankment slope liner included slope
stability. This letter summarizes the results of the analysis. Below we present a brief
background and the results of our findings.
Although a site specific seepage analysis was not performed, the design delineated in this project
manual is based on experience with similar projects and a properly constructed slope liner
embankment based on the guidelines provided in this manual should meet the SEO guidelines for
600 S Airport Road,Building A,Suite 205
Longmont,CO 80503
Phone- 303-651-1468• Fax: [phone]