Versaperm Vapour Permeability measurement

Geomembranes - Permeability Testing

The vapour permeability testing of Geomembranes is required under UK, EU and international regulations. Not only does the membrane need to be a barrier against water and water vapour, but also it needs to act against methane, CO2 and a host of other gases and chemicals.  Unfortunately all of the leeching gases react differently to every type of material or liner, and a product that is highly effective against some of them may virtually useless against another.

For example PVC is around 25 times worse as a barrier to Carbon Dioxide than it is for Nitrogen.

Geomembranes and vapour permeability testing

Versaperm equipment used to check the permeability of geomembranes

Geomembranes - uses and vapour permeability testing

It is also sensible to test any jointing seams as well as the membranbes themselves
Geomembranes can be produced using extrusion, calendering, and spread coating techniques, each of which with could produce a membrane with a different vapour permeability.  This is partly due to the different physical processes involved and partially due, even if the same basic polymer is used, to the additives, such as antioxidants, plasticizers, carbon black, fillers and lubricants (which helps with the processing).

Amongst the most popular materials to use are HDPE, LLDPE, fPP, PVC, CSPE-R, EPDM-R, and others such as ethylene interpolymer alloy (EIA-R
Wikipedia currently lists all of the following Geomembrane applications areas

  • As a barrier to odours from landfills
  • As a barrier to vapours (radon, hydrocarbons, etc.) beneath buildings
  • As containment structures for temporary surcharges
  • As covers (caps) for solid-waste landfills
  • As covers for aerobic and anaerobic manure digesters in the agriculture industry
  • As covers for power plant coal ash
  • As cutoffs within zoned earth dams for seepage control
  • As flexible forms where loss of material cannot be allowed
  • As floating reservoir covers for preventing pollution
  • As floating reservoirs for seepage control
  • As liners for all types of decorative and architectural ponds
  • As liners for brine solutions
  • As liners for golf course water holes and sand bunkers
  • As liners for heap leach pads
  • As liners for potable water
  • As liners for primary, secondary, and/or tertiary solid-waste landfills and waste piles
  • As liners for reserve water (e.g., safe shutdown of nuclear facilities)
  • As liners for secondary containment of underground storage tanks
  • As liners for solar ponds
  • As liners for the agriculture industry
  • As liners for the aquiculture industry
  • As liners for various waste conveyance canals
  • As liners for vertical walls: single or double with leak detection
  • As liners for waste liquids (e.g., sewage sludge)
  • As liners for water conveyance canals
  • As linings for emergency spillways
  • As waterproof facing for masonry and concrete dams
  • As waterproof facing for roller compacted concrete dams
  • As waterproof facing of earth and rockfill dams
  • As waterproofing liners within tunnels and pipelines
  • Beneath and adjacent to highways to capture hazardous liquid spills
  • Beneath asphalt overlays as a waterproofing layer
  • Beneath highways to prevent pollution from deicing salts
  • Liners for radioactive or hazardous waste liquid
  • To aid in establishing uniformity of subsurface compressibility and subsidence
  • To conduct water flow into preferred paths
  • To contain and transport liquids in trucks
  • To contain and transport potable water and other liquids in the ocean
  • To contain seepage losses in existing above-ground tanks
  • To control expansive soils
  • To control frost-susceptible soils
  • To face structural supports as temporary cofferdams
  • To form barrier tubes as dams
  • To prevent infiltration of water in sensitive areas
  • To shield sinkhole-susceptible areas from flowing water
  • Within cofferdams for seepage control

Testing the permeability of landfill liners and membranesThe geomembrane used to line landfill sites must be in compliance with the permeability requirements laid down by the EU's Council Directive 1999/31/EC of 26 April 1999 on the landfill of waste

Click here for a press release on permeability testing for the liner membranes of land fill sites.

Click here for information on geomembranes from Wikipedia

Click here for the UK Government information leaflet on Earthworks in Landfill Engineering

Click here for Eurocode 7 (EC7) website on geotechnical design

Click here for the UK Environmental Agency's Landfill directive