EX-21 3 a2191090zex-21.htm EXHIBIT 21
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EXHIBIT 21

SIGNIFICANT SUBSIDIARIES OF CLEAN HARBORS, INC.

 
   State of Organization   Other Business Names

CH Canada Holdings Corp

   Nova Scotia   N/A

Clean Harbors Aragonite, LLC. 

   Delaware   N/A

Clean Harbors Buttonwillow, LLC. 

   Delaware   N/A

Clean Harbors Canada, Inc. 

   New Brunswick   N/A

Clean Harbors Canada LP

   Ontario   N/A

Clean Harbors Caribe, Inc

   Puerto Rico   N/A

Clean Harbors Deer Park, L.P. 

   Delaware   N/A

Clean Harbors Disposal Services, Inc. 

   Delaware   N/A

Clean Harbors El Dorado, LLC. 

   Delaware   N/A

Clean Harbors Environmental Services, Inc. 

   Massachusetts   N/A

Clean Harbors Grassy Mountain, LLC. 

   Delaware   N/A

Clean Harbors Lone Star Corp. 

   Delaware   N/A

Clean Harbors Mercier, Inc. 

   Quebec   N/A

Clean Harbors PPM, LLC. 

   Delaware   N/A

Clean Harbors Quebec, Inc. 

   Quebec   N/A

Murphy's Waste Oil Service, Inc. 

   Massachusetts   N/A

Spring Grove Resource Recovery, Inc. 

   Delaware   N/A



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