From the GMA Techline
Subject: Landfill temperatures — I’ve had discussions with a South African consultant regarding the effects of temperature on the life expectancy of the geomembrane found in South African hazardous landfills. They have tested and found that they are getting temperatures on the membrane of up to 70°C (ca.160°F).
He has read the research from Rowe and is obviously worried. He has gone down the road of specifying material that passes the highpressure OIT only, but would like to know more about the potential problems and how to mitigate them. (Andrew, UK)
Reply: Thanks for your question, which is not at all uncommon.
We are nowhere near 70°C (ca.160°F) at our monitoring, even for bioreactor landfills, and I haven’t even tried to project out to such values. But the half-life will be short.
Where I think you can justify the geomembrane is that these are half-life predictions, and when this time is reached the GM is still there, only now it is at 50% of its original elongation and/or strength. Thus, it has a long time to go before it disintegrates.
The other consideration is that these lab studies are done under full oxygen, i.e., 21%. At the bottom of a landfill, the oxygen content might be zero, or some very low value (called starved-air conditions). In such conditions, there is no oxygen available for oxidative reduction purposes, thus much longer lifetimes are anticipated. Just how much longer is not known.
We have tried for some research in this area but nothing as of now.