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<?xml version="1.0" encoding="windows-1252"?> |
<ownershipDocument> |
| <schemaVersion> X0306 </schemaVersion> |
| <documentType> 4 </documentType> |
| <periodOfReport> 2022-07-01 </periodOfReport> |
| <issuer> |
| | <issuerCik> 0000822818 </issuerCik> |
| | <issuerName> CLEAN HARBORS INC </issuerName> |
| | <issuerTradingSymbol> CLH </issuerTradingSymbol> |
| | </issuer> |
| <reportingOwner> |
| | <reportingOwnerId> |
| | | <rptOwnerCik> 0001322710 </rptOwnerCik> |
| | | <rptOwnerName> Weber Brian P </rptOwnerName> |
| | | </reportingOwnerId> |
| | <reportingOwnerAddress> |
| | | <rptOwnerStreet1> 27 INDEPENDENCE DRIVE </rptOwnerStreet1> |
| | | <rptOwnerStreet2></rptOwnerStreet2> |
| | | <rptOwnerCity> WALPOLE </rptOwnerCity> |
| | | <rptOwnerState> MA </rptOwnerState> |
| | | <rptOwnerZipCode> 02081 </rptOwnerZipCode> |
| | | <rptOwnerStateDescription></rptOwnerStateDescription> |
| | | </reportingOwnerAddress> |
| | <reportingOwnerRelationship> |
| | | <isDirector> false </isDirector> |
| | | <isOfficer> true </isOfficer> |
| | | <isTenPercentOwner> false </isTenPercentOwner> |
| | | <isOther> false </isOther> |
| | | <officerTitle> EVP (CHESI) </officerTitle> |
| | | <otherText></otherText> |
| | | </reportingOwnerRelationship> |
| | </reportingOwner> |
| <nonDerivativeTable> |
| | <nonDerivativeTransaction> |
| | | <securityTitle> |
| <value> Common Stock </value> |
| </securityTitle> |
| | | <transactionDate> |
| <value> 2022-07-01 </value> |
| </transactionDate> |
| | | <transactionCoding> |
| <transactionFormType> 4 </transactionFormType> |
| <transactionCode> F </transactionCode> |
| <equitySwapInvolved> 0 </equitySwapInvolved> |
| </transactionCoding> |
| | | <transactionAmounts> |
| <transactionShares> |
| <value> 1805 </value> |
| <footnoteId id="F1"/> |
| </transactionShares> |
| <transactionPricePerShare> |
| <value> 90.32 </value> |
| </transactionPricePerShare> |
| <transactionAcquiredDisposedCode> |
| <value> D </value> |
| </transactionAcquiredDisposedCode> |
| </transactionAmounts> |
| | | <postTransactionAmounts> |
| <sharesOwnedFollowingTransaction> |
| <value> 64106 </value> |
| </sharesOwnedFollowingTransaction> |
| </postTransactionAmounts> |
| | | <ownershipNature> |
| <directOrIndirectOwnership> |
| <value> D </value> |
| </directOrIndirectOwnership> |
| <natureOfOwnership> |
| <value></value> |
| </natureOfOwnership> |
| </ownershipNature> |
| | | </nonDerivativeTransaction> |
| | </nonDerivativeTable> |
| <derivativeTable></derivativeTable> |
| <footnotes> |
| | <footnote id="F1"> Payment of tax liability by withholding of securities incident to vesting of securities in accordance with Rule 16b-3. </footnote> |
| | </footnotes> |
| <ownerSignature> |
| | <signatureName> /s/ Brian P. Weber </signatureName> |
| | <signatureDate> 2022-07-05 </signatureDate> |
| | </ownerSignature> |
| </ownershipDocument> |