Exhibit 21.1



SUBSIDIARIES OF THE REGISTRANT



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|----------------------------------------------------- |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|·GSE Lining Technology, Inc.                          |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | Delaware                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
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|Other trade names used:                               |  | Bentofix; GSE Conductive; GSE Conductive White; GSE Curtain Wall; GSE Fabricap; GSE FabriNet HS; GSE FabriNet UF; GSE Flexitanks; GSE Geomembranes; GSE Geonets & Geocomposites; GSE Green;
GSE GundSeal GCLs; GSE GundWall; GSE HD; GSE HD Textured; GSE HD White; GSE HyperFlex; GSE HyperFriction Flex; GSE HyperNet CP; GSE HyperNet HF; GSE HyperNet HS: GSE HyperNet UF; GSE Nonwoven Geotextiles; GSE Nonwoven Technology Company; GSE
Polylock; GSEQuickCover; GSE QuickContainment; GSE Smooth Edge; GSE Tunnelliner; GSE Ultraflex; GSE UltraFlex Textured; GSE UltraFlex White; GSE UltraFlex White Textured; GSE UltraFriction Flex; GSE VFPE; GSE White; GSE White Textured;
Geotextiles
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|·GSE Clay Lining Technology Co.                       |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | South Dakota                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
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|Other trade names used:                               |  | None                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|·GSE International, Inc.                              |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | Delaware                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
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|Other trade names used:                               |  | None                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|·GSE Lining Technology GmbH                           |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | Germany                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
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|Other trade names used:                               |  | Tunnel Liner                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
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|·Geoplastics Gesellschaft Fur Abdichtungssysteme GmbH |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | Germany                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
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|Other trade names used:                               |  | None                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|·Deposita Folientechnik GmbH                          |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | Germany                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
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|Other trade names used:                               |  | None                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|·Deposita Folientechnik GmbH                          |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | Germany                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
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|Other trade names used:                               |  | None                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|·GSE (UK) Limited                                     |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | England                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
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|Other trade names used:                               |  | None                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|·GSE Lining Technology Limited                        |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
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|Jurisdiction of organization:                         |  | England                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
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|Other trade names used:                               |  | None                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 



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|                                        |  |                       
|--------------------------------------- |  | ----------------------
|                                        | 
|·GSE Lining Technology Co. Egypt S.A.E. |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Egypt                 
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|Other trade names used:                 |  | None                  
|                                        | 
|·Hyma/GSE Lining Technology Co. S.A.E.  |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Egypt                 
|                                        | 
|Other trade names used:                 |  | None                  
|                                        | 
|·Hyma/GSE Manufacturing Co. S.A.E.      |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Egypt                 
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|Other trade names used:                 |  | None                  
|                                        | 
|·GSE Lining Technology Company Ltd.     |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Thailand              
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|Other trade names used:                 |  | None                  
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|·GSE Australia Pty Ltd.                 |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Australia             
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|Other trade names used:                 |  | None                  
|                                        | 
|·GSE Gulf Offshore Ltd.                 |  |                       
|                                        | 
|Jurisdiction of organization:           |  | British Virgin Islands
|                                        | 
|Other trade names used:                 |  | None                  
|                                        | 
|·GSE Lining Technology (Canada) Ltd.    |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Canada                
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|Other trade names used:                 |  | None                  
|                                        | 
|·BentofixTechnologies, Inc.             |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Canada                
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|Other trade names used:                 |  | None                  
|                                        | 
|·BentofixTechnologies (USA) Inc.        |  |                       
|                                        | 
|Jurisdiction of organization:           |  | Nevada                
|                                        | 
|Other trade names used:                 |  | None                  



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