See the regulatory agency document at
Beyond permeation issues and structural property changing and/or weakening warnings etc. noted in this regulatory document (talking about water, sewer, and storm etc. pipelines -- see e.g. , "Once compromised, permeated plastic piping must be replaced since the piping will retain its swollen porous state after permeation and chemical degradation..." etc.), I would only further note that it should also be realized that natural absorption of hydrocarbons into a plastic pipe wall can/will? reportedly also cause other problems e.g. with any future required or desired repair or lateral connections (taps, etc.) involving fusions to the affected pipes (.The site e.g.
e.g. now includes the caveat,
"Liquid Hydrocarbon Permeated Pipe
Liquid hydrocarbons such as crude oil, gasoline, kerosene, fuel oil, natural gas condensates and the like that are in the pipe or in surrounding soil will permeate into the pipe wall. Liquid hydrocarbon permeation generally has a minor effect on pipe that is already installed and joined. However, weak, unreliable joints can result when heat fusion is used to join polyolefin piping that has been permeated with liquid hydrocarbons.
In the field, liquid hydrocarbon permeation is indicated by a bubbly or pock-marked surface when the heating tool is removed during fusion joining. In some instances, the odor of the liquid hydrocarbon from the pipe or the surrounding soil or an enlarged pipe OD can be an indication.
Research indicates that joints made using pipes having moderate to higher levels of liquid hydrocarbon permeation will be unreliable, low-strength fusion joints. Low levels of liquid hydrocarbon permeation may not be as deleterious, but there are no quick field tests to determine the actual level of permeation..." )