Reactive geocomposite for remediating contaminated sediments

Abstract

In one application for remediating sediments, employing a geocomposite sheet eliminates the need for a thick cap or removal and subsequent ex situ treatment of the sediment. A geocomposite with at least one layer of reactive material is placed over the area to be remediated. A layer of available surcharge materials such as sand, gravel, or riprap covers the geocomposite. The weight of the surcharge materials causes pore water to flow from the sediment through the reactive layer or layers of the geocomposite. Contaminants may be trapped in this reactive layer or layers. A top or bottom layer, or both a top and bottom layer, may be provided to inhibit incursion from outside the sediment layer, while permitting appropriate flow direction of pore water into the reactive layer or layers.

We claim:  
     
         1 . A geocomposite comprising: 
 at least one first layer of geosynthetic material;    at least one second layer of geosynthetic material; and    at least one third layer composed of at least some reactive material, said at least one third layer affixed between said first and second layers,    wherein said geocomposite may be employed to remediate sediments.    
     
     
         2 . The geocomposite of  claim 1  in which said geosynthetic material is commercially available.  
     
     
         3 . The geocomposite of  claim 2  in which said commercially available geosynthetic material is selected from the group consisting of woven, non-woven, and combinations of woven and non-woven geosynthetic material.  
     
     
         4 . The geocomposite of  claim 1  in which said reactive material is commercially available.  
     
     
         5 . The geocomposite of  claim 4  in which said commercially available reactive material is selected from the group consisting of activated carbon, zeolites, particulate polymers, granular forms of commercially available chemical adsorption materials, activated carbon fabric commercially available in sheets, geosynthetic drainage net incorporating pores for holding granular reactive material, and combinations thereof.  
     
     
         6 . A remediation configuration comprising: 
 a geocomposite comprising: 
 at least one first layer of geosynthetic material;  
 at least one second layer of geosynthetic material; and  
 at least one third layer composed of at least some reactive material, said at least one third layer affixed between said first and second layers, and  
   a layer of surcharge materials placed above said geocomposite, wherein said remediation configuration may be employed to remediate sediments.    
     
     
         7 . The remediation configuration of  claim 6  in which said geosynthetic material is commercially available.  
     
     
         8 . The remediation configuration of  claim 7  in which said commercially available geosynthetic material is selected from the group consisting of woven, non-woven, and combinations of woven and non-woven geosynthetic material.  
     
     
         9 . The remediation configuration of  claim 6  in which said reactive material is commercially available.  
     
     
         10 . The remediation configuration of  claim 9  in which said commercially available reactive material is selected from the group consisting of activated carbon, zeolites, particulate polymers, granular forms of commercially available chemical adsorption materials, activated carbon fabric commercially available in sheets, geosynthetic drainage net incorporating pores for holding granular reactive material, and combinations thereof.  
     
     
         11 . The remediation configuration of  claim 6  in which said surcharge materials are selected from the group consisting of riprap, gravel, sand, and combinations thereof.  
     
     
         12 . A method for remediating sediments, comprising: 
 deploying a geocomposite in a plane, said geocomposite having at least a topmost edge when deployed approximately vertically and comprising: 
 at least one layer of geosynthetic material,  
 wherein at least one said at least one layer is composed of at least some reactive material, and  
 covering said geocomposite with a layer of surcharge materials,  
   wherein if more than one layer is used in said geocomposite, each of said layers is arranged approximately parallel to each other in said plane, and    wherein said method facilitates remediating sediments.    
     
     
         13 . The method of  claim 12  in which said layer of surcharge materials is deployed over said geocomposite along said plane.  
     
     
         14 . The method of  claim 13  in which said plane is approximately horizontal.  
     
     
         15 . The method of  claim 13  in which said plane is approximately vertical, wherein said layer of surcharge materials is deployed above said topmost edge and over the surface horizontally adjacent to said topmost edge for the length of said topmost edge.  
     
     
         16 . The method of  claim 12  in which said geosynthetic material is commercially available.  
     
     
         17 . The method of  claim 16  in which said commercially available geosynthetic material is selected from the group consisting of woven, non-woven, and combinations of woven and non-woven geosynthetic material.  
     
     
         18 . The method of  claim 12  in which said reactive material is commercially available.  
     
     
         19 . The method of  claim 18  in which said commercially available reactive material is selected from the group consisting of activated carbon, zeolites, particulate polymers, granular forms of commercially available chemical adsorption materials, activated carbon fabric commercially available in sheets, geosynthetic drainage net incorporating pores for holding granular reactive material, and combinations thereof.  
     
     
         20 . The method of  claim 12  in which said surcharge materials are selected from the group consisting of riprap, gravel, sand, and combinations thereof.  
     
     
         21 . A geocomposite for remediating sediments comprising: 
 at least one layer of geosynthetic material,    wherein at least one of said at least one layers is composed of at least some reactive material.    
     
     
         22 . The geocomposite of  claim 21  in which said geosynthetic material is commercially available.  
     
     
         23 . The geocomposite of  claim 22  in which said commercially available geosynthetic material is selected from the group consisting of woven, non-woven, and combinations of woven and non-woven geosynthetic material.  
     
     
         24 . The geocomposite of  claim 21  in which said reactive material is commercially available.  
     
     
         25 . The geocomposite of  claim 24  in which said commercially available reactive material is selected from the group consisting of activated carbon, zeolites, particulate polymers, granular forms of commercially available chemical adsorption materials, activated carbon fabric commercially available in sheets, geosynthetic drainage net incorporating pores for holding granular reactive material, and combinations thereof.  
     
     
         26 . A remediation configuration for remediating sediments comprising: 
 a geocomposite comprising: 
 at least one layer of geosynthetic material,  
 wherein at least one of said at least one layers is composed of at least some reactive material; and  
   a layer of surcharge materials placed above said geocomposite.    
     
     
         27 . The remediation configuration of  claim 26  in which said geosynthetic material is commercially available.  
     
     
         28 . The remediation configuration of  claim 27  in which said commercially available geosynthetic material is selected from the group consisting of woven, non-woven, and combinations of woven and non-woven geosynthetic material.  
     
     
         29 . The remediation configuration of  claim 26  in which said reactive material is commercially available.  
     
     
         30 . The remediation configuration of  claim 29  in which said commercially available reactive material is selected from the group consisting of activated carbon, zeolites, particulate polymers, granular forms of commercially available chemical adsorption materials, activated carbon fabric commercially available in sheets, geosynthetic drainage net incorporating pores for holding granular reactive material, and combinations thereof.  
     
     
         31 . The remediation configuration of  claim 26  in which said surcharge materials are selected from the group consisting of riprap, gravel, sand, and combinations thereof.