From the GMA Techline
9090 testing on LLDPE and HDPE
I would like to know if the 9090 testing was done strictly with 40-mil liners or was it done to multiple thickness liners, HDPE or LLDPE?
The Pennsylvania Department of Environmental Protection (Pa.DEP) is requiring I produce it with the chemical compatibility chart to get a permit for an above-ground storage tank (AST). I have seen 9090 testing results for 40-mil LLDPE. I typically like to use dual 30-mil LLDPE in the tanks that we use. Can you help with this issue?
(Brian | West Virginia)
Reply: EPA 9090 testing can, and has, been done on many liners and in all thicknesses. Ideally, the specific material one is considering should be evaluated. Since the data that results is a percentage of the nonincubated material, every test result is related to the as-manufactured material.
If you go to our website at www.geosynthetic-institute.org and click on “Accreditation,” you will find the accredited labs that do this type of testing. It is under ASTM D5322 for incubation and then ASTM D5747 for the specific testing methods. (The EPA 9090 method, per se, is no longer used).