Because this concerns substances that could be harmful to the environment the bottom seal is always HDPE with a thickness of 2 mm. This foil is chemically resistant.   
 
This means that welding of the strips must take place on site because the material is very stiff. The construction takes place on the basis of a laying certificate from Genap, whereby the basis for such a project is always formed by the layout plan designed by Genap.

The final result is geared to the storage of all types of sludge classes, or for the capture of recirculation and process water. 
 
Genap also uses very flexible and yet durable foils, such as Sarnafil MP 965-12 or the oil resistant foil Coolguard. A great advantage of these two last foils is that Genap can prefabricate the foil to size.