High Density Polyethylene (HDPE) is used as a chemical-resistant material of construction to line tanks, surnps, and trenches. Typical applications for mechanically attached HDPE linings would include trenches to convey wash-downs in chemical process areas, sumps to contain mixed hazardous wastes, storage of chemical process reagents,
containment of landfill leachate, secondary containment, and lining of waste processing vessels. Special concerns exist as to material choice and use of HDPE that will resist the tendency to stress crack as well as methods to measure stress-cracking resistance. Assurances are needed in these critical applications that proper materials have been chosen and used by the installer. This paper reviews some of the more important concerns that relate to the use and installation of HDPE liners for chemically resistant applications and how these concerns are addressed. Special focus will be placed on methods used to predict
stress-cracking resistance and on procedures to use to certify to the customer that qualified materials are used.