Geosynthetics

Our services

 

  • Design and construction of landfill cells and caps 
  • Site remediation and management 
  • Operation of waste facilities 
  • Hazardous waste cells
  •  Leachate management and drainage systems 
  • Gas conveyance systems
  • Gas barriers
  • Process ponds
  • Contaminated water treatment systems
  • Leachate ponds and digesters
  • Landfill biogas solutions
  • Design of golf courses and the associated ponds
  • Bulk excavation
  • Subdivisions
  • Roads
  • Carparks
  • Detailed excavation
  • Asbestos removal and remediation
  • Waste water treatment facilities
  • Plant and labour hire 
  • Vertical cut off wall barriers 
  • Demolition (industrial, commercial and residential)

Why geosynthetics

Evaporation and Containment Cells, Leachate Ponds, Retention Basins and more

A tailings dam is typically an earth-fill embankment dam used to store byproducts of mining operations. Conventional water retention dams can serve this purpose, but due to cost, a tailings dam is more viable. Tailings can be liquid, solid, or a slurry of fine particles. Solid tailings are often used as part of the structure itself. 


For sites where remediation or isolation of a contaminant is a goal, the act of evaporation in an engineered pond can be an effective solution, especially in the case of contaminated sediments. It is imperative that the flowback of water combined with sand, sediment, oil and other additives be contained to ensure it does not permeate into the ground. Evaporation and containment ponds are typically lined with a multilayered lining system which include leak detection and recovery systems to help identify and prevent any seepage or leaks.  


LMI provides total turn key civil construction and the subsequent installation and testing of approved lining systems for the construction of evaporation ponds and other containment requirements to the mining sector. Our lining systems are installed by our fully trained and certified welding technicians. 


LMI’s tailing cells are designed and constructed to provide tailings containment for up to 40 years (based on 500 tons per day for 40 years). The cells are approximately 21 meters deep, and each have capacity for 2.45 million tons of tailings with 2m of freeboard. This represents 13 years of capacity per cell at a process rate of 500 tonnes per day.



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Woodlawn containment cell

Materials

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HDPE & LLDPE

Gauges  

0.75mm, 1mm, 1.5mm, 2mm, 2.5mm and 3mm


Suppliers of the material
Solmax, GSE and many more reputable manufactures


High Density Polyethylene (HDPE) plastic is a ridged high tensile strength sheet. The material is sturdy and resists vigorous handling, stabilised against ultraviolet light, is resistant to both hot and cold extremes and is used in the mining, oil/gas, agriculture, marine, chemical storage and food industries. Items can be custom manufactured to suit any application. Available in a full range of sheets, thicknesses and sheet sizes. We can cut to size or deliver full sheets.
HDPE is commonly used for lining applications such as landfill caps and cells, sediment/detention basins, evaporation ponds and much more.

Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. It was the first grade of polyethylene, produced in 1933 by Imperial Chemical Industries (ICI) using a high-pressure process via free radical polymerization.

Geosynthetic clay liners (GCLs)

Geosynthetic clay liners (GCLs) are factory manufactured hydraulic barriers consisting of a layer of bentonite or other very low-permeability material supported by geotextiles and/or geomembranes, mechanically held together by needling, stitching, or chemical adhesives. The lower the hydraulic conductivity the more effective the GCL will be at retaining seepage inside of the landfill. Bentonite composed predominantly (>70%) of montmorillonite or other expansive clays, are preferred and most commonly used in GCLs. A general GCL construction would consist of two layers of geosynthetics stitched together enclosing a layer of natural or processed sodium bentonite. 


Typically, woven and/or non-woven textile geosynthetics are used, however polyethylene or geomembrane layers or geogrid geotextiles materials have also been incorporated into the design or in place of a textile layer to increase strength.

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Geotextiles

Grades range from- 100gsm - 2000 gsm

Geotextiles are a geosynthetic material that has become more popular in the civil engineering sector. The material resistant to biodegradation in most applications. Geotextiles are synthetic fibres that can be made into a flexible, porous, nonwoven or woven fabric. They are porous to water flow, to a varying degree. Geotextiles are used to filter liquid, protect underlying and overlying materials and to separate soil layers.


With fine particles like soft sand, crusher dust can be used as a cost-effective filling and packing material around water tanks; blended with natural sands to improve concrete shrinkage and water demand; and as a material to back-fill trenches with. It can also be used as a concrete aggregate used to create distinctive textures and as a substitute for concrete when creating pathways and driveways.

Drainage Net (Geonets and Geocomposites)

Tri-planar products consist of centralised middle HDPE ribs that provide channelized flow, and diagonally placed top and bottom strands that minimise geotextile intrusion. The void maintaining core structure provides higher transmissivity than bi-planar products.


Geonets are synthetic drainage materials manufactured from high-density polyethylene (HDPE) resin. They are designed to transmit fluids and gasses under many field conditions.


Geocomposites consist of a geonet heat bonded with a nonwoven needle-punched geotextile and are designed to provide drainage filtration to keep silt and soil particles from clogging the flow or to increase the friction characteristics.

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HDPE Drainer Pipe

Piping made from polyethylene is a cost effective solution for a broad range of piping problems in municipal, industrial, marine, mining, landfill, duct and agricultural applications. It has been tested and proven effective for above ground, surface, buried, slip lined, floating, and sub-surface marine applications. High-density polyethylene pipe (HDPE) can carry potable water, wastewater, slurries, 

chemicals, hazardous wastes, and compressed gases. In fact, polyethylene pipe has a long and distinguished history of service to the gas, oil, mining and other industries. It has the lowest repair frequency per mile of pipe per year compared with all other pressure pipe materials used for urban gas distribution.