Anglesea Landfill Sideliner Extension

PROJECT DESCRIPTION

Operating since 1974, Anglesea Landfill has been a Type 2 ‘valley fill’ landfill, accepting approximately 20,000 tonnes of waste, including putrescible waste, solid inert waste and fill material.

The Original Cell on the site, comprising of Cell 1 and Cell 2 has been filled to capacity. The eastern section of the Original Cell has undergone rehabilitation with a soil cover, and the southern part of Cell 1 has been rehabilitated under Stage 2 works. Cell 3, which is contiguous with Cell 2 (Stages A and B) has been constructed up to Stage C and is currently receiving waste.

The task of constructing a new cell liner, Stage D (Cell 3) along with completing the Stage C liner (Bund Wall) extension was entrusted to a civil works contractor with specialised experience in waste projects, particularly landfill rehabilitation and construction. To increase the height of the bund wall, a retaining structure was required. The reinforced soil structure specified for the bund wall height extension to be 5m high and 105m long.

OUR SOLUTION

To construct the reinforced soil structure, Geofabrics proposed the use of Maccaferri® Green Terramesh® Wire Mesh due to its unmatched speed of installation, cost effectiveness and proven performance. Based on these key benefits and previous project case studies, the Geofabrics’ proposed solution was selected.

The Green Terramesh solution is an environmentally friendly option that is typically used to form vegetated faced reinforced soil slopes (Mechanically Stabilised Earth) and embankments. It consists of pre-fabricated units of double twisted wire mesh that is stiffened with a welded mesh panel. Two integral pre-formed steel braces maintained the unit to the required 70.

Maccaferri® ParaLink® Reinforced Soil Structure Geogrid (200 kN/m) was included at each Green Terramesh layer to augment the strength of the double-twist wire mesh. As per the British Board of Agrément certificate 03/4065 for Paralink, the creep reduction factors are available for design temperatures up to 40˚C, installation damage factors for a D90 particle size up to 150 mm and chemical effects for pH of soil up to 11. This makes Paralink geogrids particularly suited to landfill and tailings dam applications.

Green Terramesh was rapid to install as all components are factory fitted. The unit was simply erected on site with the bracing angles supporting the face at the designated angle without the need for any external formwork or shuttering. Structural backfill was placed upon the soil reinforcement geogrids,and a loose rock veneer was stacked on the inside face of the Green Terramesh which negated the use of topsoil or an erosion control blanket.

Included in the initial proposal to the contractor, Geofabrics supplied a comprehensive installation manual. The contractor said the system was quick and easy to install.

PRODUCT USED

Maccaferri® Green Terramesh® Wire Mesh

• Durable wire mesh structure coated with Galmac and PoliMac provides a design life of over 120 years under normal inland application, offering greater abrasion resistance, better performance at low temperatures and enhanced UV and chemical resistance
• Improved performance compared to welded mesh facings due to the greater connection capacity provided by its integral mesh tail which avoids the need to provide a geogrid wrap to the facing unit
• Quick and simple installation with the use of bracing brackets to support the face at the designated angle
• Independently verified and tested with BBA-HAPAS certification