Laserfiche WebLink
<br /> <br />www.NewFields.com 9540 Maroon Cir, Suite 300, Englewood, CO 80112 T. 720.508.3300 <br /> <br />Date: 08/13/2024 NewFields Project 475.0106.069 <br /> <br /> <br />Newmont Mining Corporation <br />Cripple Creek and Victor Gold Mining Company <br />100 N. 3rd St. <br />Victor, CO 80860 <br /> <br /> <br />Attention: Evan Fonger <br /> Projects Manager <br />Newmont CC&V <br /> <br /> Antonio Matarrese <br /> Environmental Superintendent <br /> Newmont CC&V <br /> <br />RE: Leak Detection Trench Geomembrane Substitution <br /> <br />Dear Evan, <br /> <br />CC&V has requested that NewFields review the substitution of 40-millimeter HDPE Micro-Spike <br />geomembrane (40mil HDPE Micro-Spike) for 40-millimeter LLDPE Smooth geomembrane (40mil <br />LLDPE Smooth) in the construction of the VLF2 Phase 3 Stage B Leak Detection Trenches. <br />Currently only the 40mil LLDPE Smooth is called out on the approved drawings and in the <br />specifications, see attachments 3, 4, and 5. CC&V is requesting that 40mil HDPE Micro-Spike <br />allowed as a suitable geomembrane liner alternative in the construction of the Leak Detection <br />Trench. <br />In NewFields opinion, it is acceptable to install 40mil HDPE Micro-Spike geomembrane in the <br />Leak Detection Trench for the following reasons: <br />· All physical property values, other than the lower elongation break percentage (ASTM <br />D6693, Type IV) for the 40 mil HDPE Micro-Spike meet or exceed the current specified <br />values for 40mil LLDPE Smooth, and <br />· The geomembrane will be installed shingled with a minimum of a 5-foot overlap per panel <br />within the trench and the length of each liner panel is maximized to minimize the number of <br />shingles in the trench. Additionally, the liner panels will not be welded to each other. This <br />greatly reduces the potential risk of the liner panels from being exposed to the elongation <br />stress caused by ore loading or foundation settlement as the liner is free to move inches. <br />· Leak Detection Trench is designed to be a gravity drain system. If any fluids should reach <br />the trench due to an upset condition in the primary liner system, the fluids will drain down <br />towards the sump for recovery. For fluids to travel uphill around the shingles would require <br />the trench to be plugged.