Exhibit 99.1 LETTER OF TRANSMITTAL WASTE SYSTEMS INTERNATIONAL, INC. OFFER FOR OUTSTANDING 11 1/2% SENIOR NOTES DUE 2006 IN EXCHANGE FOR 11 1/2% SERIES B SENIOR NOTES DUE 2006 PURSUANT TO THE PROSPECTUS, DATED , 1999 THE EXCHANGE OFFER WILL EXPIRE AT MIDNIGHT, NEW YORK CITY TIME, ON , 1999, UNLESS EXTENDED (THE "EXPIRATION DATE"). TENDERS MAY BE WITHDRAWN PRIOR TO MIDNIGHT, NEW YORK CITY TIME, ON THE EXPIRATION DATE. DELIVERY TO: IBJ WHITEHALL BANK & TRUST COMPANY, EXCHANGE AGENT BY MAIL: BY HAND: BY ELECTRONIC TRANSMISSION: P.O. BOX 84 ONE STATE STREET (212) 858-2611 BOWLING GREEN STATION NEW YORK, NY 10004 CONFIRM FASCIMILE BY NEW YORK, NY 10274-0084 ATTN: SECURITIES PROCESSING TELEPHONE: ATTN: REORGANIZATIONS SUBCELLAR ONE (SC-1) (212) 858-2103 OPERATIONS DEPARTMENT TELEX NO.: 177754 DELIVERY OF THESE INSTRUCTIONS TO THE ADDRESSES OTHER THAN AS SET FORTH ABOVE, OR ELECTRONIC TRANSMISSION OF INSTRUCTIONS OTHER THAN AS SET FORTH ABOVE, WILL NOT CONSTITUTE A VALID DELIVERY. The undersigned acknowledges that he or she has received and reviewed the Prospectus dated , 1999 (the "Prospectus") of Waste Systems International, Inc., a Delaware corporation (the "Company"), and this Letter of Transmittal (the "Letter"), which together constitute the Company's offer (the "Exchange Offer") to exchange an aggregate principal amount of up to $77,500,000 of 11 1/2 Series B Senior Notes Due 2006 of the Company (the "New Notes") for a like principal amount of the issued and outstanding 11 1/2 Senior Notes Due 2006 of the Company (the "Old Notes") from the holders thereof. The New Notes will bear interest from the most recent date to which interest has been paid on the Old Notes or, if no interest has been paid on the Old Notes, from , 1999. Accordingly, if the relevant record date for interest payment occurs after the consummation of the Exchange Offer, registered holders of New Notes on such record date will receive interest accruing from the most recent date to which interest has been paid or, if no interest has been paid from , 1999. If, however, the relevant record date for interest payment occurs prior to the consummation of the Exchange Offer, registered holders of Old Notes on such record date will receive interest accruing from the most recent date to which interest has been paid or, if no interest has been paid, from , 1999. Old Notes accepted for exchange will cease to accrue interest from and after the date of consummation of the Exchange Offer, except as set forth in the immediately preceding sentence. Holders of Old Notes whose Old Notes are accepted for exchange will not receive any payment in respect of interest on such Old Notes otherwise payable on any interest payment date the record date for which occurs on or after the Expiration Date. The Company shall notify the holders of the Old Notes of any extension by means of a press release or other public announcement no later than 9:00 A.M., New York City time, on the next business day after the previously scheduled Expiration Date. This Letter is to be completed by a holder of Old Notes either if certificates are to be forwarded herewith or if a tender of certificates for Old Notes, if available, is to be made by book-entry transfer to the account maintained by the Exchange Agent at The Depository Trust Company (the "Book-Entry Transfer Facility") pursuant to the procedures set forth in the Prospectus under "The Exchange Offer--Book-Entry Transfer." Holders of Old Notes whose certificates are not immediately available, or who are unable to deliver their certificates or confirmation of the book-entry tender of their Old Notes into the Exchange Agent's account at the Book-Entry Transfer Facility (a "Book-Entry Confirmation") and all other documents required by this Letter to the Exchange Agent on or prior to the Expiration Date, must tender their Old Notes according to the guaranteed delivery procedures set forth in the Prospectus under "The Exchange Offer--Guaranteed Delivery Procedure." See Instruction 1 to this Letter, below. Delivery of documents to the Book-Entry Transfer Facility does not constitute delivery to the Exchange Agent. The undersigned has completed the appropriate boxes below and signed this Letter to indicate the action the undersigned desires to take with respect to the Exchange Offer. List below the Old Notes to which this Letter relates. If the space provided below is inadequate, the certificate numbers and principal amount of Old Notes should be listed on a separate signed schedule affixed hereto. ------------------------------------------------------------------------------------------- DESCRIPTION OF OLD NOTES ------------------------------------------------------------------------------------------- (1) (2) (3) AGGREGATE NAME(S) AND ADDRESS(ES) OF REGISTERED PRINCIPAL PRINCIPAL HOLDER(S) CERTIFICATE AMOUNT OF AMOUNT (PLEASE FILL IN, IF BLANK) NUMBER(S)* OLD NOTE(S) TENDERED** - --------------------------------------------------------------------------------------------- ---------------------------------------------- ---------------------------------------------- ---------------------------------------------- Total - ------------------------------------------------------------------------------------------- * Need not be completed if Old Notes are being tendered by book-entry transfer. ** Unless otherwise indicated in this column, a holder will be deemed to have tendered ALL of the Old Notes represented by the Old Notes indicated in column 2. See Instruction 2. Old Notes tendered hereby must be in denominations of principal amount of $1,000 or any integral multiple thereof. See Instruction 1. 2 / / CHECK HERE IF TENDERED OLD NOTES ARE BEING DELIVERED BY BOOK-ENTRY TRANSFER MADE TO THE ACCOUNT MAINTAINED BY THE EXCHANGE AGENT WITH THE BOOK-ENTRY TRANSFER FACILITY AND COMPLETE THE FOLLOWING: Name of Tendering Institution ______________________________________________ Account Number _____________________________________________________________ Transaction Code Number ____________________________________________________ / / CHECK HERE IF TENDERED OLD NOTES ARE BEING DELIVERED PURSUANT TO A NOTICE OF GUARANTEED DELIVERY PREVIOUSLY SENT TO THE EXCHANGE AGENT AND COMPLETE THE FOLLOWING: Name(s) of Registered Holder(s) ____________________________________________ Window Ticket Number (if any) ______________________________________________ Date of Execution of Notice of Guaranteed Delivery _________________________ Name of Institution which Guaranteed Delivery ______________________________ IF DELIVERED BY BOOK-ENTRY TRANSFER, COMPLETE THE FOLLOWING: Account Number _____________________________________________________________ Transaction Code Number ____________________________________________________ / / CHECK HERE IF YOU ARE A BROKER-DEALER AND WISH TO RECEIVE 10 ADDITIONAL COPIES OF THE PROSPECTUS AND 10 COPIES OF ANY AMENDMENTS OR SUPPLEMENTS THERETO WITHIN 90 DAYS AFTER THE EXPIRATION DATE. Name: ______________________________________________________________________ Address: ___________________________________________________________________ ________________________________________ 3 PLEASE READ THIS ENTIRE LETTER OF TRANSMITTAL CAREFULLY BEFORE COMPLETING ANY ABOVE. PLEASE SIGN HERE (TO BE COMPLETED BY ALL TENDER HOLDERS) (COMPLETE ACCOMPANYING SUBSTITUTE FORM W-9) Date: , 1999 X , 1999 X , 1999 Signature(s) of Owner(s) Date If a holder is tendering any Old Notes, this Letter must be signed by the registered holder(s) as the name(s) appear(s) on the certificate(s) for the Old Notes or by any person(s) authorized to become registered holder(s) by endorsements and documents transmitted herewith. If signature is by a trustee, executor, administrator, guardian, officer or other person acting in a fiduciary or representative capacity, please set forth full title. See Instruction 3 to this Letter, below. Name(s): ___________________________________________________________________ ____________________________________________________________________________ (Please Type or Print) Capacity: __________________________________________________________________ Address: ___________________________________________________________________ ____________________________________________________________________________ (Including Zip Code) SIGNATURE GUARANTEE (IF REQUIRED BY INSTRUCTION 3) Signature(s) Guaranteed by an Eligible Institution: ___________________________________________________ (Authorized Signature) ____________________________________________________________________________ (Title) ____________________________________________________________________________ (Name and Print) Dated: ______________________________________________________________ , 1999 6 INSTRUCTIONS FORMING PART OF THE TERMS AND CONDITIONS OF THE EXCHANGE OFFER FOR ALL OUTSTANDING 11 1/2% SENIOR NOTES DUE 2006 OF WASTE SYSTEMS INTERNATIONAL, INC., IN EXCHANGE FOR 11 1/2% SERIES B SENIOR NOTES DUE 2006 OF WASTE SYSTEMS INTERNATIONAL, INC. 1. DELIVERY OF THIS LETTER AND NOTICE OF GUARANTEED DELIVERY PROCEDURES. This Letter is to be completed by noteholders either if certificates are to be forwarded herewith or if tenders are to be made pursuant to the procedures for delivery by book-entry transfer set forth in the Prospectus under "The Exchange Offer--Book-Entry Transfer." Certificates for all physically tendered Old Notes, or Book-Entry Confirmation, as the case may be, as well as a properly completed and duly executed Letter (or manually signed facsimile hereof) and any other documents required by this Letter, must be received by the Exchange Agent at the address set forth herein on or prior to the Expiration Date, or the tendering holder must comply with the guaranteed delivery procedures set forth below. Holders whose certificates for Old Notes are not immediately available or who cannot deliver their certificates and all other required documents to the Exchange Agent on or prior to the Expiration Date, or who cannot complete the procedure for book-entry transfer on a timely basis, may tender their Old Notes pursuant to the guaranteed delivery procedures set forth in the Prospectus under "The Exchange Offer-- Guaranteed Delivery Procedure." Pursuant to such procedure, (i) such tender must be made through an Eligible Institution, (ii) prior to the Expiration Date, the Exchange Agent must receive from such Eligible Institution a properly completed and duly executed letter (or a facsimile thereof) and Notice of Guaranteed Delivery, substantially in the form provided by the Company (by telegram, telex, facsimile transmission, mail or hand delivery), setting forth the name and address of the holder of Old Notes and the amount of Old Notes tendered, stating that the tender is being made thereby and guaranteeing that within five New York Stock Exchange ("NYSE") trading days after the date of execution of the Notice of Guaranteed Delivery, the certificates for all physically tendered Old Notes, or a Book-Entry Confirmation, and any other documents required by this Letter will be deposited by the Eligible Institution with the Exchange Agent and (iii) the certificates for all physically tendered Old Notes, in proper form for transfer, or Book-Entry Confirmation, as the case may be, and all other documents required by this Letter, are received by the Exchange Agent within five NYSE trading days after the date of execution of the Notice of Guaranteed Delivery. THE METHOD OF DELIVERY OF THIS LETTER, THE OLD NOTES AND ALL OTHER REQUIRED DOCUMENTS IS AT THE ELECTION AND RISK OF THE TENDERING HOLDERS, BUT THE DELIVERY WILL BE DEEMED MADE ONLY WHEN ACTUALLY RECEIVED OR CONFIRMED BY THE EXCHANGE AGENT. IF OLD NOTES ARE SENT BY MAIL, IT IS SUGGESTED THAT THE MAILING, RETURN RECEIPT REQUESTED, BE MADE SUFFICIENTLY IN ADVANCE OF THE EXPIRATION DATE TO PERMIT DELIVERY TO THE EXCHANGE AGENT PRIOR TO MIDNIGHT, NEW YORK CITY TIME, ON THE EXPIRATION DATE. See the Prospectus under "The Exchange Offer." 2. PARTIAL TENDERS (NOT APPLICABLE TO HOLDERS WHO TENDER BY BOOK-ENTRY TRANSFER). If less than all of the Old Notes evidenced by a physically submitted certificate are to be tendered, the tendering holder(s) should fill in the aggregate principal amount of Old Notes to be tendered in the box entitled "Description of Old Notes--Principal Amount Tendered." A reissued certificate representing the balance of nontendered Old Notes will be sent to such tendering holder, unless otherwise provided in the appropriate box on this Letter, promptly after the Expiration Date. ALL OF THE OLD NOTES DELIVERED TO THE EXCHANGE AGENT WILL BE DEEMED TO HAVE BEEN TENDERED UNLESS OTHERWISE INDICATED. 7 3. SIGNATURES ON THIS LETTER; BOND POWERS AND ENDORSEMENTS; GUARANTEE OF SIGNATURES. If this Letter is signed by the registered holder of the Old Notes tendered hereby, the signature must correspond exactly with the name as written on the face of the certificates without any change whatsoever. If any tendered Old Notes are owned of record by two or more joint owners, all such owners must sign this Letter. If any tendered Old Notes are registered in different name on several certificates, it will be necessary to complete, sign and submit as many separate copies of this Letter as there are different registrations of certificates. When this Letter is signed by the registered holder or holders of the Old Notes specified herein and tendered hereby, no endorsements of certificates or separate bond powers are required. If, however, New Notes are to be issued, or any untendered Old Notes are to be released, to a person other than the registered holder, then endorsements of any certificates transmitted hereby or separate bond powers are required. Signatures on such certificate(s) or bond powers must be guaranteed by an Eligible Institution. If this Letter is signed by a person other than the registered holder or holders of any certificate(s) specified herein, such certificate(s) must be endorsed or accompanied by appropriate bond powers, in either case signed exactly as the name or names of the registered holder or holders appear(s) on the certificate(s) and signatures on such certificate(s) or bond powers must be guaranteed by an Eligible Institution). Endorsement on certificates for Old Notes or signatures on bond powers required by this Instruction 3 must be guaranteed by a firm which is a member of a registered national securities exchange or a member of the National Association of Securities Dealers, Inc. or by a commercial bank or trust company having an office or correspondent in the United States (an "Eligible Institution"). Signatures on this Letter need not be guaranteed by an Eligible Institution, provided the Old Notes are tendered: (i) by a registered holder of Old Notes (which term, for purposes of the Exchange Offer, includes any participant in the Book-Entry Transfer Facility system whose name appears on a security position listing as the holder of such Old Notes) who has not completed the box entitled "Special Issuance Instructions" or "Special Delivery Instructions" on this Letter or (ii) for the account of an Eligible Institution. 4. SPECIAL ISSUANCE AND DELIVERY INSTRUCTIONS. Tendering holders of Old Notes should indicate in the applicable box the name and address to which New Notes issued pursuant to the Exchange Offer and/or substitute certificates evidencing Old Notes not exchanged are to be issued or sent, if different from the name or address of the person signing this Letter. In the case of issuance in a different name, the employer identification or social security number of the person named must also be indicated. Holders tendering Old Notes by book-entry transfer may request that Old Notes not exchanged be credited to such account maintained at the Book-Entry Transfer Facility as such holder may designate herein. If no such instructions are given, such Old Notes not exchanged will be returned to the name or address of the person signing this Letter. 5. TRANSFER TAXES. The Company will pay all transfer taxes, if any, applicable to the transfer of Old Notes to it or its order pursuant to the Exchange Offer. If however, New Notes and/or substitute Old Notes not exchanged are to be delivered to, or are to be registered or issued in the name of, any person other than the registered holder of the Old Notes tendered hereby, or if tendered Old Notes are registered in the name of any person other than the person signing this Letter, or if a transfer tax is imposed for any reason other than the transfer of Old Notes to the Company or its order pursuant to the Exchange Offer, the amount of any 8 such transfer taxes (whether imposed on the registered holder or any other persons) will be payable by the tendering holder. If satisfactory evidence of payment of such taxes or exemption therefrom is not submitted herewith, the amount of such transfer taxes will be billed directly to such tendering holder. EXCEPT AS PROVIDED IN THIS INSTRUCTION 5, IT WILL NOT BE NECESSARY FOR TRANSFER TAX STAMPS TO BE AFFIXED TO THE OLD NOTES SPECIFIED IN THIS LETTER. 6. WAIVER OF CONDITIONS. The Company reserves the absolute right to waive satisfaction of any or all conditions provided in the Prospectus. 7. NO CONDITIONAL TENDERS. No alternative, conditional, irregular or contingent tenders will be accepted. All tendering holders of Old Notes, by execution of this Letter, shall waive any right to receive notice of the acceptance of their Old Notes for exchange. Neither the Company, the Exchange Agent nor any other person is obligated to give notice of any defect or irregularity with respect to any tender of Old Notes nor shall any of them incur any liability for failure to give any such notice. 8. MUTILATED, LOST, STOLEN OR DESTROYED OLD NOTES. Any holder whose Old Notes have been mutilated, lost, stolen or destroyed should contact the Exchange Agent at the address indicated above for further instructions. 9. REQUESTS FOR ASSISTANCE OR ADDITIONAL COPIES. Questions relating to the procedure for tendering, as well as requests for additional copies of the Prospectus and this Letter, may be directed to the Exchange Agent at the address and telephone number indicated above. 9