of cargo from container 206 via discharge tube 104 load vent ports 106 project through apertures in bulkhead 202 the top of liner 102 to provide access for loading the cargo fig3 illustrates a method of fabricating liner 102 without heat sealing for ease of discussion the fabrication process for liner 102 and for ports 502 shown below in fig5 will be discussed in terms of fabrication on site and prior to loading however those skilled in the art will recognize that a preferred embodiment of this invention is the use of prefabricated liners and prefabricated ports 502 in fig3 a liner 102 has an open end the material used to fabricate liner 102 is typically a flexible material such as 6 mil polyethylene or 6 mil polypropylene due to the flexibility end portions 302 may be folded over to form an end wall fig3 b shows the next step in the fabrication process wherein end portions 302 are folded such that they overlap the edges of end portions 302 are sealed via double stick tape to form wall tape seal 304 fig3 c shows the end seals 306 formed by folding the ends over the end wall of liner 102 the end seals 306 are formed with double stick tape in the same manner that wall tape seal 304 was formed after sealing excess material resulting from folding can be trimmed or taped against the wall of liner 102 as a reinforcing layer those skilled in the art will recognize that the location of wall tape seal 304 can vary in orientation or distance from a particular edge likewise end seals 306 can be formed against the end wall of liner 102 or against the.