Integrated PAC-based cap delivery system, apparatus and compositions
Disclosed are novel solutions in which a preexisting sediment capping system is integrated with improvements such as a cap ingredient processing and delivery apparatus, cap processing method and novel compositional cap product, whereby a hazardous site is remediated by delivering at least one novel cap composition layer over the contaminated subaqueous waterway or terrestrial substrate floor. One embodiment includes a powdered activated carbon (“PAC”) based cap layer produced by the system and methodology disclosed, the cap layer ingredients comprising predetermined ratio amounts of dry PAC and dry powdered 2-Hydroxypropyl guar gum (“HGG”) used as a safe and effective delivery ingredient, blended in a cap processing and delivering apparatus with a dewatered sand semi-slurry, the processed resulting capping composition being delivered in a manner such that a novel PAC cap layer is provided to a cap placement area in need of remediation.
1. An integrated apparatus for processing capping ingredients and delivering a capping composition on a subaqueous waterway bottom substrate comprising: a cylindrically elongated flow housing frame having a first and second ingredient feed port and a dewatered sand input chute; an axeless auger extending longitudinally through the frame with both ends affixed such that the auger is able to be rotated by a motor; wherein the auger simultaneously processes dry and semi-dry ingredients to form a blended capping composition and the composition is discharged through a discharge port to a blending screen under the port capable of further processing the composition prior to delivery to a metering hopper and conveyor belt sub-system; and a capping composition pool to deliver the composition through a water column such that it settles, creating a cap on the water bottom.
2. The integrated apparatus of claim 1 , wherein the apparatus allows for the blending and delivery of a plurality of capping ingredients such that the resultant blended composition is a powdered activated carbon (PAC) cap layer.