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                                                                Exhibit 4.18


                            TERM PROMISSORY NOTE B


$19,000,000.00                                           Boston, Massachusetts
                                                         April 12, 2001


     FOR VALUE RECEIVED, the undersigned, (collectively, the "Debtors"), hereby
unconditionally and jointly and severally promise to pay to the order of
CONGRESS FINANCIAL CORPORATION (NEW ENGLAND), a Massachusetts corporation (the
"Payee"), at the offices of Payee at One Post Office Square, Boston,
Massachusetts 02109, or at such other place as the Payee or any holder hereof
may from time to time designate, the principal sum of NINETEEN MILLION DOLLARS
($19,000,000.00) in lawful money of the United States of America and in
immediately available funds, in eighty-four (84) consecutive monthly
installments (or earlier as hereinafter provided) on the first day of each month
commencing May 1, 2001 of which the first eighty-three (83) installments shall
each be in the amount of TWO HUNDRED TWENTY-SIX THOUSAND ONE HUNDRED NINETY AND
48/100 DOLLARS ($226,190.48), and the last installment, which shall be due and
payable on the third anniversary of the date of the Loan Agreement (as
hereinafter defined), shall be in the amount of the entire unpaid balance of
this Note.

     Each Debtor hereby further promises jointly and severally to pay interest
to the order of Payee on the unpaid principal balance hereof at the Interest
Rate. Such interest shall be paid in like money at said office or place from the
date hereof, commencing May 1, 2001 and on the first day of each month
thereafter until the indebtedness evidenced by this Note is paid in full.
Interest payable upon and after an Event of Default or termination or non-
renewal of the Loan Agreement shall be payable upon demand.

     For purposes hereof,

     a)     The term "Interest Rate" shall mean, a rate of three and one-half
(3.5%) percent per annum in excess of the greater of (i) eight and one-half
percent (8.5%) or (ii) Prime Rate; provided, that, upon and after an Event of
Default or termination of the Loan Agreement, at Payee's option, the Interest
Rate shall mean a rate of six (6.0%) percent per annum in excess of the greater
of (i) eight and one-half percent (8.5%) or (ii) Prime Rate.

     b)     The term "Prime Rate" shall mean the rate from time to time publicly
announced by First Union National Bank, or its successors, as its prime rate,
whether or not such announced rate is the best rate available at such bank,

     c)     The term "Event of Default" shall mean an Event of Default as such
term is defined in the Loan Agreement, and

     d)     The term "Loan Agreement" shall mean the Amended and Restated Loan
and Security Agreement, dated April 12, 2001, as amended, between Debtors and
Payee, as the same


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now exists or may hereafter be amended, modified, supplemented, extended,
renewed, restated or replaced.

     Unless otherwise defined herein, all capitalized terms used herein shall
have the meaning assigned thereto in the Loan Agreement.

     The Interest Rate payable hereunder shall increase or decrease by an amount
equal to each increase or decrease, respectively, in the Prime Rate, effective
on the first day of the month after any change in the Prime Rate is announced.
The increase or decrease shall be based on the Prime Rate in effect on the last
day of the month in which any such change occurs. Interest shall be calculated
on the basis of a three hundred sixty (360) day year and actual days elapsed. In
no event shall the interest charged hereunder exceed the maximum permitted under
the laws of the Commonwealth of Massachusetts or other applicable law.

     This Note is issued pursuant to the terms and provisions of the Loan
Agreement to evidence the Term Loan B by Payee to Debtors. This Note is secured
by the Collateral described in the Loan Agreement and all notes, guarantees,
security agreements and other agreements, documents and instrument now or at any
time hereafter executed and/or delivered by any Debtor or any other party in
connection therewith (all of the foregoing, together with the Loan Agreement, as
the same now exist or may hereafter be amended, modified, supplemented, renewed,
extended, restated or replaced, being collectively referred to herein as the
"Financing Agreements"), and is entitled to all of the benefits and rights
thereof and of the other Financing Agreements. At the time any payment is due
hereunder, at its option, Payee may charge the amount thereof to any account of
any Debtor maintained by Payee.

     If any payment of principal or interest is not made when due hereunder, or
if any other Event of Default shall occur for any reason, or if the Loan
Agreement shall be terminated or not renewed for any reason whatsoever, then and
in any such event, in addition to all rights and remedies of Payee under the
Financing Agreements, applicable law or otherwise, all such rights and remedies
being cumulative, not exclusive and enforceable alternatively, successively and
concurrently, Payee may, at its option, declare any or all of Debtors'
obligations, liabilities and indebtedness owing to Payee under the Loan
Agreement and the other Financing Agreements (the "Obligations"), including,
without limitation, all amounts owing under this Note, to be due and payable,
whereupon the then unpaid balance hereof, together with all interest accrued
thereon, shall forthwith become due and payable, together with interest accruing
thereafter at the then applicable Interest Rate stated above until the
indebtedness evidenced by this Note is paid in full, plus the costs and expenses
of collection hereof, including, but not limited to, attorneys' fees and legal
expenses.

     Each Debtor (i) waives diligence, demand, presentment, protest and notice
of any kind, (ii) agrees that it will not be necessary for Payee to first
institute suit in order to enforce payment of this Note and (iii) consents to
any one or more extensions or postponements of time of payment, release,
surrender or substitution of collateral security, or forbearance or other
indulgence, without notice or consent. The pleading of any statute of
limitations as a defense to any demand against Debtor is expressly hereby waived
by each Debtor. Upon any Event of


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Default or termination or non-renewal of the Loan Agreement, Payee shall have
the right, but not the obligation to setoff against this Note all money owed by
Payee to any Debtor.

     Payee shall not be required to resort to any Collateral for payment, but
may proceed against any Debtor and any guarantors or endorsers hereof in such
order and manner as Payee may choose. None of the rights of Payee shall be
waived or diminished by any failure or delay in the exercise thereof.

     The validity, interpretation and enforcement of this Note and the other
Financing Agreements and any dispute arising in connection herewith or therewith
shall be governed by the internal laws of the Commonwealth of Massachusetts
(without giving effect to principles of conflicts of law).

     Each Debtor irrevocably consents and submits to the non-exclusive
jurisdiction of the Courts of the Commonwealth of Massachusetts and the United
States District Court for the District of Massachusetts and waives any objection
based on venue or forum non conveniens with respect to any action instituted
                  ----- --- ----------
therein arising under this Note or any of the other Financing Agreements or in
any way connection with or related or incidental to the dealings of Debtors and
Payee in respect of this Note or any of the other Financing Agreements or the
transactions related hereto or thereto, in each case whether now existing or
hereafter arising, and whether in contract, tort, equity or otherwise, and
agrees that any dispute arising out of the relationship between Debtor and Payee
or the conduct of such persons in connection with this Note or otherwise shall
be heard only in the courts described above (except that Payee shall have the
right to bring any action or proceeding against any Debtor or its property in
the courts of any other jurisdiction which Payee deems necessary or appropriate
in order to realize on the Collateral or to otherwise enforce its rights against
Debtor or its property).

     Each Debtor hereby waives personal service of any and all process upon it
and consents that all such service of process may be made by certified mail
(return receipt requested) directed to it and service so made shall be deemed to
be completed five (5) days after the same shall have been so deposited in the
U.S. mails, or, at Payee's option, by service upon Debtor in any other manner
provided under the rules of any such courts. Within thirty (30) days after such
service, Debtors shall appear in answer to such process, failing which Debtor
shall be deemed in default and judgment may be entered by Payee against Debtors
for the amount of the claim and other relief requested.

     EACH DEBTOR WAIVES ANY RIGHT TO TRIAL BY JURY OF ANY CLAIM, DEMAND, ACTION
OR CAUSE OF ACTION (i) ARISING UNDER THIS NOTE, OR (ii) IN ANY WAY CONNECTED
WITH OR RELATED OR INCIDENTAL TO THE DEALINGS BETWEEN DEBTOR AND PAYEE IN
RESPECT OF THIS NOTE OR ANY OF THE OTHER FINANCING AGREEMENTS OR THE
TRANSACTIONS RELATED HERETO OR THERETO IN EACH CASE WHETHER NOW EXISTING OR
HEREAFTER ARISING, AND WHETHER IN CONTRACT, TORT, EQUITY OR OTHERWISE. DEBTOR
AGREES AND CONSENTS THAT ANY SUCH CLAIM, DEMAND, ACTION OR CAUSE OF ACTION SHALL
BE DECIDED BY COURT TRIAL WITHOUT A JURY.


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     The execution and delivery of this Note has been authorized by the Board of
Directors and by any necessary vote or consent of the stockholders of Debtors.
Each Debtor hereby authorizes Payee to complete this Note in any particulars
according to the terms of the loan evidenced hereby.

     This Note shall be binding upon the successors and assigns of each Debtor
and inure to the benefit of Payee and its successors, endorsees and assigns.
Whenever used herein, the term "Debtor" shall be deemed to include its
successors and assigns and the term "Payee" shall be deemed to include its
successors, endorsees and assigns. If any term or provision of this Note shall
be held invalid, illegal or unenforceable, the validity of all other terms and
provisions hereof shall in no way be affected thereby. This Note is an
instrument under seal under Massachusetts law.

WITNESS/ATTEST:                     CLEAN HARBORS, INC.




                                    By: /s/ Stephen H. Moynihan
-----------------                      --------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President

WITNESS/ATTEST:                 CLEAN HARBORS ENVIRONMENTAL
                                    SERVICES, INC.


                                    By: /s/ Stephen H. Moynihan
-----------------                      --------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President



WITNESS/ATTEST:                 CLEAN HARBORS KINGSTON FACILITY
                                    CORPORATION


                                    By: /s/ Stephen H. Moynihan
-----------------                      --------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President



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WITNESS/ATTEST:                     CLEAN HARBORS OF BRAINTREE, INC.

                                       /s/ Stephen H. Moynihan
___________________________         By:--------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President


WITNESS/ATTEST:                     CLEAN HARBORS SERVICES, INC.

                                        /s/ Stephen H. Moynihan
___________________________         By:-------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President


WITNESS/ATTEST:                     CLEAN HARBORS OF NATICK, INC.

                                       /s/ Stephen H. Moynihan
---------------------------         By:--------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President

WITNESS/ATTEST:                     CLEAN HARBORS OF CONNECTICUT, INC.

                                       /s/ Stephen H. Moynihan
---------------------------         By:--------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President


WITNESS/ATTEST:                     MURPHY'S WASTE OIL SERVICE, INC.

                                       /s/ Stephen H. Moynihan
---------------------------         By:--------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President

WITNESS/ATTEST:                     MR. FRANK, INC.

                                       /s/ Stephen H. Moynihan
---------------------------         By:--------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President


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WITNESS/ATTEST:                 SPRING GROVE RESOURCE RECOVERY,
                                    INC.

                                   /s/ Stephen H. Moynihan
---------------------------     By: ------------------------------
[Corporate Seal]                    Name: Stephen H. Moynihan
                                    Title:Senior Vice President

WITNESS/ATTEST                  HARBOR MANAGEMENT CONSULTANTS,
                                    INC.

                                    /s/ Stephen H. Moynihan
---------------------------     By: --------------------------------
[Corporate Seal]                    Name:  Stephen H. Moynihan
                                    Title: Senior Vice President


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