GEOWEB Slope Protection & Load Support System

Project Name: Site Access to Mining Pond

Project Location: Western United States

Site Access Solution to Evaporation Pond Integrates 3D Soil Stabilization System; Utilizes On-Site Waste Rock

PROJECT SYNOPSIS:

A mining engineering company contacted Presto Geosystems to help create a stable ramp over a liner system into a 1,000,000-square-foot evaporation pond. The pond was being built at a large open-pit mineral mine in the Western United States. The ramp to the pond would have to support large loaders and dump trucks required to remove accumulated sediment from the pond and protect the liner system from damage.

PROJECT SUMMARY:

The GEOWEB® 3D Soil Confinement System, utilizing the mine’s on-site rock infill, was selected to help stabilize the access ramp into the pond.

To support an articulated truck’s load and driving forces—the largest piece of equipment that would use the ramp—Presto recommended the GEOWEB 6-inch-deep material. The material was anchored with three polyester tendons per panel and the patented ATRA® Tendon Clip load transfer device every fourth cell downslope. The tendons were anchored to a 4-inch PVC pipe, buried 2 feet below grade at the crest of the slope in the same anchor trench that secured the liner system.

The liner system consisted of, from bottom to top, a geosynthetic clay liner (GCL), a 60-mil HDPE secondary
geomembrane, a 200-mil geonet, and a 60-mil textured HDPE primary geomembrane.

PROJECT RESULTS:

Approximately 75,000 square feet of Presto GEOWEB material was installed on the 16-foot vertical, 3H:1V ramp and infilled with on-site mine waste without anchor penetrations through the liner system.

GEOWEB CONFINEMENT & LOAD TRANSFER DEVICE:

Presto’s GEOWEB soil confinement system, filled with on-site mine waste rock provided lateral load reinforcement to support traffic. The use of on-site waste rock reduced project costs.

The ATRA® Tendon Clips (high-strength load transfer devices) were used to connect tendons with the GEOWEB cell walls for the most secure connection. With 2X the pull-through strength of any other load transfer device, the number required per section was reduced by half, saving time and installation costs.