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                                                                  EXHIBIT 31.2

                   CERTIFICATION OF CHIEF FINANCIAL OFFICER

I, Mark S. Burgess, certify that:

       I have reviewed this annual report on Form 10-K of Clean Harbors, Inc.;

       Based on my knowledge, this report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to
make the statements made, in light of the circumstances under which such
statements were made, not misleading with respect to the period covered by
this report;

       Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects
the financial condition, results of operations and cash flows of the
registrant as of, and for, the periods presented in this report;

       The registrant's other certifying officer(s) and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined
in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over
financial reporting (as defined in Exchange Act Rules 13a-15(f) and
15d-15(f)) for the registrant and we have:


       (a)  Designed such disclosure controls and procedures, or caused such
            disclosure controls and procedures to be designed under our
            supervision, to ensure that material information relating to the
            registrant, including its consolidated subsidiaries, is made
            known to us by others within those entities, particularly during
            the period in which this report is being prepared;

       (b)  Designed such internal control over financial reporting, or
            caused such internal control over financial reporting to be
            designed under our supervision, to provide reasonable assurance
            regarding the reliability of financial reporting and the
            preparation of financial statements for external purposes in
            accordance with generally accepted accounting principles;

       (c)  Evaluated the effectiveness of the registrant's disclosure
            controls and procedures and presented in this report our
            conclusions about the effectiveness of the disclosure controls
            and procedures, as of the end of the period covered by this
            report based on such evaluation; and

       (d)  Disclosed in this report any change in the registrant's internal
            control over financial reporting that occurred during the
            registrant's most recent fiscal quarter that has materially
            affected, or is reasonably likely to materially affect, the
            registrant's internal control over financial reporting; and

       The registrant's other certifying officer(s) and I have disclosed,
based on our most recent evaluation of internal control over financial
reporting, to the registrant's auditors and the audit committee of the
registrant's board of directors (or persons performing the equivalent
functions);

       (a)  All significant deficiencies and material weaknesses in the
            design or operation of internal control over financial reporting
            which are reasonably likely to adversely affect the registrant's
            ability to record, process, summarize and report financial
            information; and

       (b)  Any fraud, whether or not material, that involves management or
            other employees who have significant role in the registrant's
            internal control over financial reporting.

Date: March 31, 2005                              /s/ Mark S. Burgess
                                       ---------------------------------------
                                                    MARK S. BURGESS
                                       PRESIDENT AND CHIEF EXECUTIVE OFFICER