##### 



Exhibit 4.15

December 23, 2002

U S Liquids Inc.
411 N. Sam Houston Pkwy. E.
Houston, TX 77060
Attention: Treasurer

Re: Waiver, Eleventh Amendment and Consent

Ladies and Gentlemen:

Please refer to the Second Amended and Restated Credit Agreement dated
as of February 3, 1999 (as previously amended, the Credit Agreement) among U S
Liquids Inc. (the Company), various financial institutions and Bank of
America, N.A. (formerly known as Bank of America National Trust and Savings
Association), as Agent. Capitalized terms used but not otherwise defined herein
have the respective meanings assigned thereto in the Credit Agreement.

1.     Introduction.

(a)  The Company has advised the Agent and the Banks that an Event of
Default resulting from the resignation by Michael P. Lawlor from his position as
the Chairman of the Board and Chief Executive Officer of the Company, which was
previously waived by the Required Banks pursuant to a waiver letter dated
October 4, 2002 (the 10/4 Waiver Letter) and a waiver letter dated October 25,
2002 (the 10/25 Waiver Letter; together with the 10/4 Waiver Letter, the
Prior Waiver Letters), continues to exist.

(b)  The Company has advised the Agent and the Banks that the Company
and/or its Subsidiaries plan to sell (i) the Purchased Assets (as defined in the
Asset Purchase Agreement dated as of December 5, 2002 between U S Liquids Great
Lakes, Inc. (Great Lakes) and American Waste, Inc.) and (ii) the assets
described in (A) the letter of intent, dated as of December 26, 2002, between
Diamond Environmental Corp. and the Company and (B) the separate equipment list
relating to the letter, dated December 11, 2002, from EnviroVac, attached
together hereto as Exhibit B (collectively, the Remaining Texas Assets).

(c)  The Company has requested that the Required Banks agree to certain
modifications to the calculations of various financial covenants set forth in
Section 10.6 of the Credit Agreement.

2.     Waiver, Amendments and Consents.

(a)  At the Companys request, and subject to the agreements of the
Company set forth herein, the Required Banks hereby waive through April 15, 2003
the Event of Default described in Section 1(a) (the Waived Default); provided
that this waiver shall terminate immediately upon (x) a breach of any of the
terms of this letter or (y) the occurrence of any other Event of Default or
Unmatured Event of Default under the Credit Agreement. Upon the expiration or
termination of this waiver, the Waived Default shall be deemed immediately
reinstated, and the Agent and the Banks may thereafter exercise their rights and
remedies under the Credit Agreement with respect thereto without further notice.





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U S Liquids Inc.
December 23, 2002
Page 2

(b)  The Company and the Required Banks agree as follows:



| |                                                                                                                                                                                                                                                                       
| | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| | (i) Notwithstanding anything in Credit Agreement to the
contrary, the Company may add back up to $4,000,000 in the aggregate of
non-cash charges taken by the Company during the Fiscal Quarters ending
December 31, 2002 and/or March 31, 2003 in calculating EBITDA.



| |                                                                                           
| | ------------------------------------------------------------------------------------------
| | (ii) Section 10.6.3 of the Credit Agreement is amended in its
entirety to read as follows:



| |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
| | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| | 10.6.3 Funded Debt to Adjusted EBITDA Ratio. (a) Not permit
the Funded Debt to Adjusted EBITDA Ratio for any Computation Period,
commencing with the Computation Period ending on December 31, 2002, to
be greater than 4.0 to 1, and (b) not permit, on any Measurement Date,
the ratio of (i) Funded Debt on such Measurement Date to (ii) Adjusted
EBITDA for the 12 months ending on such Measurement Date to be greater
than 4.00 to 1. As used herein, Measurement Date means each of
January 31, 2003 and February 28, 2003. The Company shall deliver to
the Administrative Agent within 30 days following each Measurement Date
an officers certificate setting forth the calculation under clause (b)
as of such Measurement Date.



| |                                                                                                             
| | ------------------------------------------------------------------------------------------------------------
| | (iii) Clause (i) of Section 11.2.1(e) of the Credit Agreement
is amended in its entirety to read as follows:



| |                                                            
| | -----------------------------------------------------------
| | "(i) at any time prior to April 15, 2003, 4.00 to 1.0 and.

(c)  Notwithstanding anything in the Credit Agreement to the contrary,
the Required Banks consent to (i) the proposed sale of the Purchased Assets by
Great Lakes so long as the gross cash consideration paid by the purchaser in
connection with such sale is at least $1,337,500 and (ii) the proposed sale of
the Remaining Texas Assets so long as the gross cash consideration paid by the
purchasers in connection with such sale is at least $475,000.

(d)  Notwithstanding anything to the contrary contained in the Credit
Agreement or the Prior Waiver Letters, the Banks agree that the Company may
defer to January 15, 2003 the $3,400,000 reduction in the Commitment Amount that
was scheduled to occur on December 31, 2002.

3.     Terms and Conditions of Waiver, Amendments and Consents. In
consideration of the foregoing waiver, amendments and consents, the Company
agrees with the Agent and the Required Banks as follows:

(a)  Limitation on Outstandings. The limitation on the Total
Outstandings set forth in Section 3(a) of the Prior Waiver Letters shall remain
in effect through April 15, 2003; provided that the Company shall not be
permitted to obtain Loans to make payments under the finite bonding program with
AIG (as described in the memorandum dated November 6, 2002 from Gary Grossman to
Michael Staunton of Bank of America, N.A. and related and included documents) in
an aggregate principal amount greater than $2,500,000.





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U S Liquids Inc.
December 23, 2002
Page 3

(b)  Reduction of the Commitment Amount; Mandatory Prepayment. The
Company will comply with the commitment reduction requirements set forth in the
Credit Agreement and the Prior Waiver Letters; provided that the Company will
apply (i) any portion of the Holdback Amount (as defined in the 10/4 Waiver
letter) received by the Company after the date hereof and (ii) the Net Cash
Proceeds from Asset Sales involving the Great Lakes assets and Remaining Texas
Assets to make a voluntary prepayment of Loans in accordance with Section 6.2 of
the Credit Agreement and, unless the Company otherwise requests, the Company
shall not be required to apply such proceeds to reduce the Commitment Amount.

(c)  Appraisal; Field Examination. Without limiting the generality of
any of the provisions of the Credit Agreement or any other Loan Document, the
Company shall, on or before December 31, 2002, (i) deliver to the Administrative
Agent a copy of the report of Foothill Capital Corporation containing the
results of the field examination performed by Foothill Capital Corporation and
(ii) pay all invoiced fees (including retainer fees) of an appraiser selected by
the Administrative Agent to evaluate the assets of the Company and its
Subsidiaries.

4.     Effectiveness. This letter (other than the agreement of the Banks
set forth in Section 2(d)) shall become effective upon receipt by the Agent of
(a) counterparts hereof (or facsimiles thereof) executed by the Company and the
Required Banks, (b) a confirmation of the Guarantors substantially in the form
of Exhibit A, (c) a waiver fee for each Bank in an amount equal to 0.125% of
such Banks Commitment, (d) copies of resolutions of the Board of Directors of
the Company authorizing the execution and delivery by the Company of this letter
and the performance by the Company of its obligations hereunder and (e) evidence
that the Company has paid all fees and expenses of the Agent (including all
attorneys fees and expenses) incurred on or prior to the date hereof. The
agreement of the Banks set forth in Section 2(d) shall become effective upon (i)
receipt of the Agent of counterparts hereof (or facsimiles thereof) executed by
the Company and each Bank and (ii) satisfaction of the conditions set forth in
clauses (b) through (e).

5.     Miscellaneous.

(a)  This letter is limited to the matters specifically set forth herein
and shall not be deemed to constitute a waiver or consent with respect to any
other matter whatsoever. The Agent and the Banks hereby reserve all of their
rights, powers and remedies under the Credit Agreement and applicable law.

(b)  This letter may be executed in counterparts and by the parties
hereto on separate counterparts.

(c)  This letter shall be governed by the laws of the State of Illinois
applicable to contracts made and to be performed entirely within such State.

(d)  Except as otherwise expressly amended or modified herein, each of
the Credit Agreement and the Prior Waiver Letters (including the
representations, warranties, covenants and Events of Default contained therein)
shall remain in full force and effect and are hereby ratified and confirmed in
all respects.





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U S Liquids Inc.
December 23, 2002
Page 4

[SIGNATURE PAGES FOLLOW]





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##### 



U S Liquids Inc.
December 23, 2002
Page 5

Please acknowledge the foregoing by signing a copy of this letter and
returning it to the Agent.

| |  |  |  |                                  |  |  | 
| |  |  |  | -------------------------------- |  |  | 
| |  |  |  | Very truly yours,               
| |  |  |  |                                  |  | 
| |  |  |  | BANK OF AMERICA, N.A., as Agent 
| |  |  |  |                                  |  | 
| |  |  |  | By:                              |  | 
| |  |  |  |                                  |  | 
| |  |  |  | Title:                           |  | 
| |  |  |  |                                  |  | 
| |  |  |  |                                  |  | 
| |  |  |  | BANK OF AMERICA, N.A., as a Bank
| |  |  |  |                                  |  | 
| |  |  |  | By:                              |  | 
| |  |  |  |                                  |  | 
| |  |  |  | Title:                           |  | 
| |  |  |  |                                  |  | 
| |  |  |  |                                  |  | 
| |  |  |  | FLEET NATIONAL BANK             
| |  |  |  |                                  |  | 
| |  |  |  | By:                              |  | 
| |  |  |  |                                  |  | 
| |  |  |  | Title:                           |  | 
| |  |  |  |                                  |  | 
| |  |  |  |                                  |  | 
| |  |  |  | BANK ONE, NA                    
| |  |  |  |                                  |  | 
| |  |  |  | By:                              |  | 
| |  |  |  |                                  |  | 
| |  |  |  | Title:                           |  | 
| |  |  |  |                                  |  | 
| |  |  |  |                                  |  | 
| |  |  |  | THE BANK OF NOVA SCOTIA         
| |  |  |  |                                  |  | 
| |  |  |  | By:                              |  | 
| |  |  |  |                                  |  | 
| |  |  |  | Title:                           |  | 
| |  |  |  |                                  |  | 
| |  |  |  |                                  |  | 
| |  |  |  | UNION BANK OF CALIFORNIA        
| |  |  |  |                                  |  | 
| |  |  |  | By:                              |  | 
| |  |  |  |                                  |  | 
| |  |  |  | Title:                           |  | 
| |  |  |  |                                  |  | 





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##### 



U S Liquids Inc.
December 23, 2002
Page 6

|                         |  |  |  |                        |  |  | 
|------------------------ |  |  |  | ---------------------- |  |  | 
|                         |  |  |  | COMERICA BANK         
|                         |  |  |  |                        |  | 
|                         |  |  |  | By:                    |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  | Title:                 |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  | WELLS FARGO BANK, N.A.
|                         |  |  |  |                        |  | 
|                         |  |  |  | By:                    |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  | Title:                 |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  | BNP PARIBAS           
|                         |  |  |  | By:                    |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  | Title:                 |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  | By:                    |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  | Title:                 |  | 
|                         |  |  |  |                        |  | 
|                         |  |  |  |                        |  | 
|ACKNOWLEDGED AND AGREED: |  |  |  |                       
|                         |  |  |  |                        |  | 
|U S LIQUIDS INC.         |  |  |  |                       
|                         |  |  |  |                        |  | 
|By:                      |  |  |  |                        |  | 
|                         |  |  |  |                        |  | 
|Title:                   |  |  |  |                        |  | 
|                         |  |  |  |                        |  | 





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##### 



CONFIRMATION

Dated as of December 23, 2002



|To: |  | Bank of America, N.A., individually and as Administrative Agent,
and the other financial institutions party to the
Credit Agreement referred to below
|--- |  | -----------------------------------------------------------------------------------------------------------------------------------------------------

Please refer to the waiver, amendment and consent letter dated as of
December 23, 2002 (the Waiver and Consent) with respect to the Second Amended
and Restated Credit Agreement dated as of February 3, 1999 (as amended, the
Credit Agreement) among U S Liquids Inc., various financial institutions (the
Banks) and Bank of America, N.A. (formerly known as Bank of America National
Trust and Savings Association), as administrative agent (the Administrative
Agent).

Each of the undersigned hereby confirms to the Administrative Agent and
the Banks that such undersigned has received a copy of the Waiver and Consent
and that, after giving effect to the Waiver and Consent and the transactions
contemplated thereby, each Loan Document to which such undersigned is a party
continues in full force and effect and is the legal, valid and binding
obligation of such undersigned, enforceable against such undersigned in
accordance with its terms.

| |  |                                             
| |  | --------------------------------------------
| |  | EARTH BLENDS, INC.                          
| |  | MBO, INC.                                   
| |  | THE NATIONAL SOLVENT EXCHANGE CORP.         
| |  | PARALLEL PRODUCTS OF FLORIDA, INC.          
| |  | PARALLEL PRODUCTS OF KENTUCKY, INC.         
| |  | RE-CLAIM ENVIRONMENTAL LOUISIANA, L.L.C.    
| |  | ROMIC ENVIRONMENTAL TECHNOLOGIES CORPORATION
| |  | USL FIRST SOURCE, INC.                      
| |  | U S LIQUIDS GREAT LAKES, INC.               
| |  | U S LIQUIDS OF HOUSTON, L.L.C.              
| |  | U S LIQUIDS OF DALLAS, L.L.C.               
| |  | U S LIQUIDS OF CENTRAL TEXAS, L.L.C.        
| |  | U S LIQUIDS OF CONNECTICUT, INC.            
| |  | U S LIQUIDS OF GREATER CHICAGO, INC.        
| |  | U S LIQUIDS OF PENNSYLVANIA, INC.           
| |  | U S LIQUIDS OF TEXAS, INC.                  
| |  | U S LIQUIDS LP HOLDING CO.                  
| |  | U S LIQUIDS NORTHEAST, INC.                 
| |  | U S LIQUIDS TERMINAL SERVICES, INC.         
| |  | U S LIQUIDS OF DETROIT, INC.                
| |  | U S LIQUIDS OF FLORIDA, INC.                
| |  | USL ENVIRONMENTAL SERVICES, INC.            
| |  | USL GENERAL MANAGEMENT, INC.                





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##### 



| |  |                                                       |  | 
| |  | ----------------------------------------------------- |  | 
| |  | USL PARALLEL PRODUCTS OF CALIFORNIA                  
| |  |                                                       |  | 
| |  | WASTE RESEARCH AND RECOVERY, INC.                    
| |  |                                                       |  | 
| |  | WASTE STREAM ENVIRONMENTAL, INC.                     
| |  |                                                       |  | 
| |  | By:                                                   |  | 
| |  |                                                       |  | 
| |  | Name:                                                 |  | 
| |  |                                                       |  | 
| |  | Title:                                                |  | 
| |  |                                                       |  | 
| |  |                                                       |  | 
| |  | U S LIQUIDS OF LA., L.P.                             
| |  |                                                       |  | 
| |  | By: MBO, Inc., its General Partner                   
| |  |                                                       |  | 
| |  | By:                                                   |  | 
| |  |                                                       |  | 
| |  | Name:                                                 |  | 
| |  |                                                       |  | 
| |  | Title:                                                |  | 
| |  |                                                       |  | 
| |  |                                                       |  | 
| |  | USL MANAGEMENT LIMITED PARTNERSHIP                   
| |  |                                                       |  | 
| |  | By: USL General Management, Inc., its General Partner
| |  |                                                       |  | 
| |  | By:                                                   |  | 
| |  |                                                       |  | 
| |  | Name:                                                 |  | 
| |  |                                                       |  | 
| |  | Title:                                                |  | 
| |  |                                                       |  | 
| |  |                                                       |  | 
| |  | GEM MANAGEMENT, INC.                                 
| |  |                                                       |  | 
| |  | By:                                                   |  | 
| |  |                                                       |  | 
| |  | Name:                                                 |  | 
| |  |                                                       |  | 
| |  | Title:                                                |  | 
| |  |                                                       |  | 





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##### 



EXHIBIT B

REMAINING TEXAS ASSETS

USL Houston
Equipment Held for Sale
December 2002

|                              |  |             |  |          |  |       |  |                   |  |        |  |                   
|----------------------------- |  | ----------- |  | -------- |  | ----- |  | ----------------- |  | ------ |  | ------------------
|Year                          |  | Make        |  | Model    |  | ID    |  | VIN #             |  | GVW    |  | Power Unit/Trailer
|                              |  |             |  |          |  |       |  |                   |  |        |  |                   
|(Vehicle/Trailer Description) |  |             |  | (Vehicle |  | (GVW) |  |                  
|                              |  |             |  |          |  |       |  | Identification    |  |        |  |                   
|                              |  |             |  |          |  |       |  | Number.)          |  |        |  |                   
|                             
|1999                          |  | WALKER      |  |          |  | H-39  |  | 1W9S43245XN001028 |  | 13,100 |  | TRAILER           
|1997                          |  | TRAILMASTER |  |          |  | H-36  |  | 190FA452XW3F13052 |  | 13,300 |  | TRAILER           
|1999                          |  | WALKER      |  |          |  | H-28  |  | 1W9S43243XN001027 |  | 13,160 |  | TRAILER           
|1997                          |  | TRAILMASTER |  |          |  | H-40  |  | 190FA4521W3F13053 |  | 13,300 |  | TRAILER           
|1999                          |  | WALKER      |  |          |  | H-61  |  | 1W9S4324XXN001025 |  | 13,100 |  | TRAILER           
|1998                          |  | TRAILMASTER |  |          |  | H-35  |  | 190FA4521W3F13277 |  | 13,250 |  | TRAILER           
|1988                          |  | POLAR       |  |          |  | H-65  |  | 1PMS34221J1009321 |  | 11,800 |  | TRAILER           
|1985                          |  | POLAR       |  |          |  | H-58  |  | 1PMS34224F1006825 |  | 12,500 |  | TRAILER           
|1987                          |  | KARI        |  |          |  | H-38  |  | 141ST4227E1008850 |  | 13,600 |  | TRAILER           
|1985                          |  | KARI        |  |          |  | H-44  |  | 141ST422XF1008858 |  | 13,600 |  | TRAILER           
|1999                          |  | WALKER      |  |          |  | H-50  |  | 1W9S43241XN001026 |  | 13,300 |  | TRAILER           
|1988                          |  | POLAR       |  |          |  | H-41  |  | 1PMS3422XJ1009320 |  | 10,200 |  | TRAILER           
|