Plastic pipes favoured for contaminated land

Jeremy Bowman from Uponor says that polyethylene based and metallic pipe systems have been assessed for their ability to stop petrol migrating through the pipe wall, fitting or joint and into water contained within the pipe. A quantitative test was devised that is capable of distinguishing between the different pipe systems. Key results were then obtained for the migration of benzene, toluene, ethyl benzene and xylene.

“Plain PE pipe is relatively translucent to petrol (estimated 5% petrol, 95% water).” Explains Bowman. “But the inclusion of a layer of welded aluminium in the middle of the wall of a PE pipe stops the migration of the petrol!”

However, Bowman says that to create an effective pipe network that stops petrol migration, the use of metallic fittings is required. “Iron based pipe systems show significant migration of petrol into the pipe and other contamination believed to arise from the lining used to stop the corrosion of these iron based pipe systems.”

He insists that the iron based systems were the worst performing, except for just plain PE pipes. His observations are therefore significant for pipe systems to carry potable water and to be installed in ground that may contain contamination arising from a previous industrial use.

“PE-Al-PE pressure pipe systems with metallic fittings offer the best and most secure solution for the transport of water in contaminated land,” he says.