Abstract: A height adjustable water-tight sump for use in hazardous waste storage systems. The sump comprises an inspection cover, an access cover, a riser section and a base. The riser section has alternately adjacent threaded sections and grip sections in appropriate areas along the riser for height adjustment of the sump in that, at a desired height, the riser section may be cut off to conform to that desired height. To form the sump the riser section is threadably engageable with the base, the access cover is threadably engageable with the riser section, and the inspection cover is threadably engageable with the access cover.

Abstract: A permeable membrane system comprised of at least two sheets, at least one of the two sheets being a grooved permeable membrane having regularly spaced grooves on at least one surface, the grooves having a predetermined spacing factor, the grooved permeable membrane either having essentially no barrier layer or having a barrier layer on one grooved surface, the sheets being positioned in a configuration with the grooves of that one grooved surface of the grooved permeable membrane sheet forming feed channels with a surface of another sheet which covers that one grooved surface, the grooves being about 0.5 to about 100 mils wide and deep and the feed channels being used to deliver the feed stream to the membrane surface. Preferably, both sheets are permeable membranes. The grooves in the sheets are preferably about 5 to about 35 mils wide and deep for reverse osmosis, about 0.5 to about 20 mils wide and deep for gas separation, and about 15 to about 75 mils wide and deep for ultrafiltration.