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Filed Pursuant to Rule 424(b)(3)
Registration No. 333-211234

PROSPECTUS

$250,000,000

Clean Harbors, Inc.

5.125% Senior Notes due 2021 and Related Guarantees

        On March 17, 2016, we issued $250.0 million aggregate principal amount of 5.125% Senior Notes due 2021 (the "old notes") in an unregistered private placement as additional notes under an indenture dated December 7, 2012.

        We are offering to exchange up to $250.0 million aggregate principal amount of 5.125% Senior Notes due 2021 (the "new notes") that we have registered under the Securities Act of 1933 (the "Securities Act") for up to all of the $250.0 million aggregate principal amount of outstanding old notes. This prospectus refers to the new notes, the old notes and the $595.0 million aggregate principal amount of 5.125% Senior Notes due 2021 which were outstanding under the indenture prior to March 17, 2016 and are now outstanding (the "initial notes") collectively as the "notes." The old notes and the initial notes are, and the new notes will be, fully and unconditionally and jointly and severally guaranteed by substantially all of our existing and future domestic restricted subsidiaries. The guarantees are, however, subject to customary release provisions under which, in particular, the guarantee of any of our domestic restricted subsidiaries will be released if we sell such subsidiary to an unrelated third party in accordance with the terms of the indenture which governs the notes. Such guarantees of the new notes are securities which have been registered under the Securities Act and are being offered, along with the new notes, by this prospectus in exchange for the old notes and related guarantees.

        The Exchange Offer

        The New Notes

        See "Risk Factors" beginning on page 10 to read about factors you should consider in connection with the exchange offer.

        Each broker-dealer that receives new notes for its own account in exchange for old notes acquired by such broker-dealer as a result of market-making activities or other trading activities must deliver a prospectus in connection with a resale of the new notes and provide us in the letter of transmittal with a signed acknowledgement of this obligation. The letter of transmittal states that by so acknowledging and by delivering a prospectus, any such broker-dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act. A broker-dealer may use this prospectus, as amended or supplemented from time to time, in connection with any such resale of new notes. We have agreed that for a period of 180 days after the expiration date of the exchange offer, we will make this prospectus available to broker-dealers for use in connection with any such resale of new notes. See "Plan of Distribution."

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the new notes or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is May 19, 2016.



TABLE OF CONTENTS

 
  Page  

SUMMARY

    1  

RISK FACTORS

    10  

USE OF PROCEEDS

    25  

RATIO OF EARNINGS TO FIXED CHARGES

    25  

CAPITALIZATION

    26  

SELECTED HISTORICAL CONSOLIDATED FINANCIAL INFORMATION

    27  

DESCRIPTION OF OTHER INDEBTEDNESS

    29  

THE EXCHANGE OFFER

    31  

DESCRIPTION OF THE NOTES

    41  

UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS

    83  

PLAN OF DISTRIBUTION

    87  

LEGAL MATTERS

    87  

EXPERTS

    87  



        In this prospectus, unless the context otherwise requires, "we," "our," "us," "Clean Harbors" or the "Company" refers collectively to Clean Harbors, Inc. and its subsidiaries. In this prospectus, all references to our consolidated financial statements include the respective notes thereto. Unless otherwise specified with respect to certain amounts which are stated in Canadian dollars ("Cdn $"), all dollar amounts in this prospectus are in U.S. dollars ($).


WHERE YOU CAN FIND ADDITIONAL INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the Securities and Exchange Commission (the "SEC"). Our SEC filings are available to the public over the Internet at the SEC's web site at http://www.sec.gov. Copies of the documents we file with the SEC can be read at the SEC's public reference facility at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of its public reference facility.

        We have filed this prospectus with the SEC as part of a registration statement on Form S-4 under the Securities Act. This prospectus does not contain all of the information set forth in the registration statement because some parts of the registration statement are omitted in accordance with the rules and regulations of the SEC. The registration statement and its exhibits are available for inspection and copying as set forth above.


DOCUMENTS INCORPORATED BY REFERENCE

        We are "incorporating by reference" in this prospectus some of the documents we file with the SEC. This means that we can disclose important information to you by referring you to those documents. The information in the documents incorporated by reference is considered to be part of this prospectus. Information in specified documents that we file with the SEC after the date of this prospectus will automatically update and supersede information in this prospectus. We incorporate by reference the documents listed below and any future filings we may make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 after the date of filing of the initial registration statement relating to the exchange offer and prior to the termination of any offering of securities offered by this prospectus:

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        Information contained in this prospectus supplements, modifies or supersedes, as applicable, the information contained in earlier-dated documents incorporated by reference. Information contained in later-dated documents incorporated by reference supplements, modifies or supersedes, as applicable, the information contained in this prospectus or in earlier-dated documents incorporated by reference.

        We will provide a copy of the documents we incorporate by reference (other than exhibits, unless the exhibit is specifically incorporated by reference into the filing requested), at no cost, to you if you submit a request to us by writing to or telephoning us at the following address or telephone number:

Clean Harbors, Inc.
42 Longwater Drive
Norwell, Massachusetts 02061-9149
Telephone: (781) 792-5100
Attention: Executive Offices

        If you would like to request any documents, please do so by no later than June 15, 2016 in order to receive them before the expiration of the exchange offer.

        You should rely only on the information contained or incorporated by reference in this prospectus. We have not authorized any other person to provide you with different or additional information. If anyone provides you with different or additional information, you should not rely on it. The information contained or incorporated by reference in this prospectus is accurate only as of the date on the front cover of this prospectus or the date of the document incorporated by reference. Our business, financial condition, results of operations and prospects may have changed since those respective dates. We are not making an offer to exchange the new notes for old notes in any jurisdiction where the offer or exchange is not permitted.


Market and Related Information

        We obtained the market and related information used in this prospectus from our own research, surveys or studies conducted by third parties and industry or general publications, such as EI Digest, and other publicly available sources. Industry and general publications and surveys generally state that they have obtained information from sources believed to be reliable. Although we have not independently verified all of the market data and related information contained in this prospectus which we have obtained from third party sources, we believe such data and information is accurate as of the date of this prospectus or the respective earlier dates specified herein.


Forward-Looking Statements

        This prospectus includes "forward-looking statements," as defined by federal securities laws, with respect to our financial condition, results of operations and business and our expectations or beliefs concerning future events. Words such as, but not limited to, "believe," "expect," "anticipate," "estimate," "intend," "plan," "targets," "likely," "will," "would," "could" and similar expressions or phrases identify forward-looking statements. Such statements may include, but are not limited to, statements about future financial and operating results, the Company's plans, objectives, expectations and intentions and other statements that are not historical facts.

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        All forward-looking statements involve risks and uncertainties. Many risks and uncertainties are inherent in the environmental, industrial and energy services industries. Others are more specific to our operations. The occurrence of the events described, and the achievement of the expected results, depend on many events, some or all of which are not predictable or within our control. Actual results may differ materially from expected results.

        Factors that may cause actual results to differ from expected results include, among others:

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        All future written and verbal forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to above. We undertake no obligation, and specifically decline any obligation, to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. In light of these risks, uncertainties and assumptions, the forward-looking events discussed in this prospectus might not occur.

        See "Risk Factors" in this prospectus for a more complete discussion of these risks and uncertainties and for other risks and uncertainties. These factors and the other risk factors described in this prospectus are not necessarily all of the important factors that could cause actual results to differ materially from those expressed in any of our forward-looking statements and other unknown or unpredictable factors also could harm our results. Consequently, actual results or developments anticipated by us may not be realized and, even if substantially realized, they may not have the expected consequences to, or effects on, us. Given these uncertainties, prospective investors are cautioned not to place undue reliance on such forward-looking statements.

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SUMMARY

        This summary highlights information contained elsewhere in this prospectus, is not complete and does not contain all of the information that may be important to you. We urge you to read this entire prospectus carefully, including the "Risk Factors" section and the consolidated financial statements and related notes incorporated by reference herein.


Our Company

        We are North America's leading provider of environmental, energy and industrial services. We serve a diverse customer base with over 250,000 customers, including a majority of the Fortune 500, across the chemical, energy, manufacturing and additional markets, as well as numerous government agencies. These customers rely on us to deliver a broad range of services including but not limited to end-to-end hazardous waste management, emergency spill response, industrial cleaning and maintenance, and recycling services. Through our acquisition in December 2012 of Safety-Kleen, Inc. ("Safety-Kleen"), we are also the largest re-refiner and recycler of used oil in the world and the largest provider of parts cleaning and environmental services to commercial, industrial and automotive customers in North America.

        We have a network of more than 450 service locations across 47 states, eight Canadian provinces, Puerto Rico, Mexico, and Trinidad. Those service locations include service centers, satellite locations, branches, active hazardous waste management properties, lodging facilities and oil processing facilities. The service centers and branches are the principal sales and service centers from which we provide our environmental, energy and industrial services. The active hazardous waste management properties include incineration facilities, commercial and non-commercial landfills, wastewater treatment facilities, treatment, storage and over 100 disposal facilities ("TSDFs"), solvent recovery management and recycling facilities, locations specializing in polychlorinated biphenyls ("PCBs") management, oil accumulation centers, oil terminals and oil re-refineries. Some of our properties offer multiple services.


Our Services

        During 2015, we reported our business in six operating segments, consisting of:

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The Environmental Services Industry

        The environmental services, or hazardous waste management, industry was "created" in 1976 with the passage of the Resource Conservation and Recovery Act, or "RCRA." RCRA requires waste generators to distinguish between "hazardous" and "non-hazardous" wastes, and to treat, store and dispose of hazardous waste in accordance with specific regulations. This new regulatory environment, combined with strong economic growth, increased corporate concern about environmental liabilities, and the early stage nature of the hazardous waste management industry contributed initially to rapid growth in the industry. However, by the mid to late 1990s, the hazardous waste management industry was characterized by overcapacity, minimal regulatory advances and pricing pressure. We believe that since that time competition has been reduced through consolidation and that new regulations have increased the overall barriers to entry.

        The collection and disposal of solid and hazardous wastes are subject to local, state, provincial and federal requirements and regulations, which regulate health, safety, the environment, zoning and land use. Among these regulations in the United States is the Comprehensive Environmental Response, Compensation and Liability Act of 1980, or "CERCLA," which holds generators and transporters of hazardous substances, as well as past and present owners and operators of sites where there has been a hazardous release, strictly, jointly and severally liable for environmental cleanup costs resulting from the release or threatened release of hazardous substances. Canadian companies are regulated under similar regulations, but the responsibility and liability associated with the waste passes from the generator to the transporter or receiver of the waste, in contrast to provisions of CERCLA. The largest generators of hazardous waste materials are companies in the chemical, petrochemical, primary metals, paper, furniture, aerospace and pharmaceutical industries.


Corporate Information

        Clean Harbors, Inc. was incorporated in Massachusetts in 1980. Our corporate offices are located at 42 Longwater Drive, Norwell, MA 02161 (telephone (781) 792-5000). Shares of our common stock trade on the New York Stock Exchange under the symbol "CLH." Our website address is www.cleanharbors.com. The information contained or incorporated in our website is not part of this prospectus.

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The Exchange Offer

Background

  On March 17, 2016, we completed a private placement of the old notes. In connection with that private placement, we entered into a registration rights agreement with Goldman Sachs & Co., the initial purchaser of the old notes, in which we agreed to deliver this prospectus to you and to make the exchange offer.

The Exchange Offer

 

We are offering to exchange up to $250.0 million aggregate principal amount of our new notes which have been registered under the Securities Act for up to all of the $250.0 million aggregate principal amount of our old notes. You may tender old notes only in denominations of $2,000 and any integral multiple of $1,000.

Resale of New Notes

 

Based on interpretive letters of the SEC staff to third parties, we believe that you may resell and transfer the new notes issued pursuant to the exchange offer in exchange for old notes without compliance with the registration and prospectus delivery provisions of the Securities Act if:

 

you are acquiring the new notes in the ordinary course of your business for investment purposes;

 

you have no arrangement or understanding with any person to participate in the distribution of the new notes; and

 

you are not our affiliate as defined under Rule 405 under the Securities Act.

 

If you fail to satisfy any of these conditions, you must comply with the registration and prospectus delivery requirements of the Securities Act in connection with a resale of the new notes.

 

Broker-dealers that acquired old notes directly from us, but not as a result of market-making activities or other trading activities, must comply with the registration and prospectus delivery requirements of the Securities Act in connection with a resale of the new notes.

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Each broker-dealer that receives new notes for its own account pursuant to the exchange offer in exchange for old notes that it acquired as a result of market-making or other trading activities must deliver a prospectus in connection with any resale of the new notes and provide us with a signed acknowledgement of this obligation.

Transfer Restrictions

 

The new notes have been registered under the Securities Act and generally will be freely transferable. We do not intend to list the notes on any securities exchange.

Limited Market

 

The new notes will be newly issued securities for which there is currently no market. Although the initial purchaser of the old notes has informed us that it intends to make a market in the new notes, it is not obligated to do so and may discontinue market-making at any time without notice. Accordingly, a liquid market for the new notes may not develop or be maintained.

Consequences If You Do Not Exchange Your Old Notes

 

Old notes that are not tendered in the exchange offer or are not accepted for exchange will continue to bear legends restricting their transfer. You will not be able to offer or sell the old notes unless:

 

an exemption from the requirements of the Securities Act is available to you;

 

we register the resale of old notes under the Securities Act; or

 

the transaction requires neither an exemption from nor registration under the requirements of the Securities Act.

 

After the completion of the exchange offer, we will no longer have an obligation to register the old notes, except in limited circumstances.

Expiration Date

 

5:00 p.m., New York City time, on June 22, 2016 unless we extend the exchange offer.

Conditions to the Exchange Offer

 

The exchange offer is subject to limited, customary conditions, which we may waive.

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Procedures for Tendering Old Notes

 

If you wish to accept the exchange offer, you must deliver to the exchange agent:

 

either a completed and signed letter of transmittal or, for old notes tendered electronically, an agent's message from The Depository Trust Company, which we refer to as "DTC," stating that the tendering participant agrees to be bound by the letter of transmittal and the terms of the exchange offer;

 

your old notes, either by tendering them in physical form or by timely confirmation of book-entry transfer through DTC; and

 

all other documents required by the letter of transmittal.

 

These actions must be completed before the expiration of the exchange offer.

 

If you hold old notes through DTC, you must comply with its standard procedures for electronic tenders, by which you will agree to be bound by the letter of transmittal.

 

By signing, or by agreeing to be bound by the letter of transmittal, you will be representing to us that:

 

you will be acquiring the new notes in the ordinary course of your business;

 

you have no arrangement or understanding with any person to participate in the distribution of the new notes; and

 

you are not our affiliate as defined under Rule 405 under the Securities Act.

 

See "The Exchange Offer—Procedures for Tendering."

Guaranteed Delivery Procedures for Tendering Old Notes

 

If you cannot meet the expiration deadline or you cannot deliver your old notes, the letter of transmittal or any other documentation to comply with the applicable procedures under DTC standard operating procedures for electronic tenders in a timely fashion, you may tender your notes according to the guaranteed delivery procedures set forth under "The Exchange Offer—Guaranteed Delivery Procedures."

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Special Procedures for Beneficial Holders

 

If you beneficially own old notes which are registered in the name of a broker, dealer, commercial bank, trust company or other nominee and you wish to tender in the exchange offer, you should contact that registered holder promptly and instruct that person to tender on your behalf. If you wish to tender in the exchange offer on your own behalf, you must, prior to completing and executing the letter of transmittal and delivering your old notes, either arrange to have the old notes registered in your name or obtain a properly completed bond power from the registered holder. The transfer of registered ownership may take considerable time.

Withdrawal Rights

 

You may withdraw your tender of old notes at any time before the exchange offer expires.

Tax Consequences

 

The exchange pursuant to the exchange offer will not be a taxable event for U.S. federal income tax purposes. See "Certain United States Federal Income Tax Considerations."

Use of Proceeds

 

We will not receive any proceeds from the exchange or the issuance of new notes in connection with the exchange offer.

Exchange Agent

 

U.S. Bank National Association is serving as exchange agent in connection with the exchange offer. The address and telephone number of the exchange agent are set forth under "The Exchange Offer—Exchange Agent."

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Summary Description of the New Notes

        The old notes are, and the new notes will be, governed by an indenture among Clean Harbors, Inc., as the issuer, the guarantors party thereto and U.S. Bank National Association, as trustee. The following is a summary of certain terms of the indenture and the notes and is qualified in its entirety by the more detailed information contained under the heading "Description of the Notes" elsewhere in this prospectus. Furthermore, certain description in this prospectus of provisions of the indenture are summaries of such provisions and are qualified by reference to the indenture.

        The form and terms of the new notes are substantially identical to the form and terms of the old notes, except that:

        The new notes will evidence the same debt as the old notes and will rank equally with the old notes. The same indenture will govern the old notes, the new notes, and the $595.0 million aggregate principal amount of initial notes. This prospectus refers to the old notes, the new notes and the initial notes collectively as the "notes."

Issuer   Clean Harbors, Inc. (the "Issuer").

New Notes Offered

 

$250,000,000 aggregate principal amount of 5.125% Senior Notes due 2021.

Maturity Date

 

June 1, 2021.

Interest Payments

 

Interest on the notes is payable semi-annually in arrears on June 1 and December 1 of each year.

Guarantees

 

The old notes are, and the new notes will be, guaranteed by substantially all of the Company's current and future subsidiaries organized in the United States. Each guarantor for the old notes is, and each guarantor for the new notes will be, a 100% owned subsidiary of Clean Harbors, Inc. and its guarantee is or will be both full and unconditional and joint and several. The guarantees are, however, subject to customary release provisions under which, in particular, the guarantee of any of our domestic restricted subsidiaries will be released if we sell such subsidiary to an unrelated third party in accordance with the terms of the indenture which governs the notes. The old notes are not, and the new notes will not be, guaranteed by our Canadian or other foreign subsidiaries.

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Ranking   The old notes are, and the new notes will be, our and the guarantors' unsecured senior obligations. The old notes rank, and the new notes will rank, equally with our and the guarantors' existing and future senior obligations (including, without limitation, the $595.0 million aggregate principal amount of initial notes and our outstanding $800.0 million aggregate principal amount of 5.25% senior notes due 2020) and senior to any future indebtedness that is specifically subordinated to the notes and the guarantees. The notes are effectively subordinated to all of our and our subsidiaries' secured indebtedness to the extent of the value of the assets securing such debt. The notes are also structurally subordinated to all indebtedness and other liabilities, including trade payables, of our subsidiaries that are not guarantors of the notes.

 

 

As of March 31, 2016, we and our guarantor subsidiaries had no outstanding loans under our revolving credit facility, but we then had $145.2 million of letters of credit outstanding under our revolving credit facility and no capital lease obligations. The notes and the guarantees rank effectively junior to debt (including loans and reimbursement obligations in respect of outstanding letters of credit) under our revolving credit agreement and any future capital lease obligations to the extent of the value of the assets securing such secured debt. Furthermore, our non-guarantor subsidiaries had as of March 31, 2016 approximately $98.0 million of total liabilities (excluding intercompany liabilities and debt). The notes and the guarantees rank structurally junior to those obligations of our non-guarantor subsidiaries.

Optional Redemption

 

We may redeem some or all of the notes at any time on or after December 1, 2016, at the redemption prices described in "Description of the Notes—Redemption—Optional Redemption," plus accrued and unpaid interest to the date of redemption. At any time, or from time to time, prior to December 1, 2016, we may also redeem some or all of the notes at a price equal to 100% of the principal amount thereof plus the make-whole premium described under "Description of the Notes—Redemption—Optional Redemption."

Change of Control

 

If we experience a Change of Control (as defined under "Description of the Notes—Certain Covenants—Change of Control"), we will be required to make an offer to repurchase the notes at a price equal to 101% of the principal amount thereof, plus accrued and unpaid interest to the date of repurchase.

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Certain Covenants   The indenture governing the notes restricts our ability and the ability of our restricted subsidiaries to, among other things:

 

incur or guarantee additional indebtedness (including, for this purpose, reimbursement obligations under letters of credit) or issue certain preferred stock;

 

pay dividends or make other distributions to our stockholders;

 

purchase or redeem capital stock or subordinated indebtedness;

 

make investments;

 

create liens;

 

incur restrictions on the ability of our restricted subsidiaries to pay dividends or make other payments to us;

 

sell assets, including capital stock of our subsidiaries;

 

consolidate or merge with or into other companies or transfer all or substantially all of our assets; and

 

engage in transactions with affiliates.


 

 

These covenants are subject to a number of important qualifications and exceptions. See "Description of the Notes—Certain Covenants."

 

 

If the notes attain investment grade ratings, then our and our restricted subsidiaries' obligation to comply with many of the covenants will be suspended while such investment grade ratings remain in effect. See "Description of the Notes—Certain Covenants—Suspension of Covenants."

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RISK FACTORS

        Before you tender your old notes, you should be aware that there are various risks involved in an investment in the notes, including those we describe below. You should consider carefully these risk factors together with all of the information included or referred to in this prospectus before you decide to tender your old notes in this exchange offer.

Risks Related to the Exchange Offer and the Notes

         If you fail to exchange your old notes in accordance with the terms described in this prospectus, you may not be able to sell your old notes.

        Old notes which you do not tender or we do not accept will, following the exchange offer, continue to be restricted securities. You may not offer or sell untendered old notes except pursuant to an exemption from, or in a transaction not subject to, the Securities Act and applicable state securities laws. We will issue new notes in exchange for your old notes pursuant to the exchange offer only if you satisfy the procedures and conditions described in this prospectus. These procedures and conditions include timely receipt by the exchange agent of your old notes and a properly completed and duly executed letter of transmittal.

        Because we anticipate that most holders of old notes will elect to exchange their old notes, the market for any old notes remaining after the completion of the exchange offer will likely be adversely affected. Any old notes tendered and exchanged in the exchange offer will reduce the aggregate principal amount of the old notes outstanding. Following the exchange offer, if you did not tender your old notes, you generally will not have any further registration rights and your old notes will continue to be subject to transfer restrictions. Accordingly, you may not be able to sell your old notes.

         Even if you accept the exchange offer, you may not be able to sell your new notes in the future at favorable prices.

        There is no public market for the notes. Despite our registration of the new notes that we are offering in the exchange offer:

        The liquidity of, and trading market for, the notes may also be adversely affected by, among other things:

        A real or perceived economic downturn or higher interest rates could therefore cause a decline in the market price of the notes and thereby negatively impact the market for the notes. Because the notes may be thinly traded, it may be more difficult to sell and accurately value the notes. In addition, as has recently been evident in the current turmoil in the global financial markets, the present economic slowdown and the uncertainty over its breadth, depth and duration, the entire high-yield bond market can experience sudden and sharp price swings, which can be exacerbated by large or sustained sales by major investors in the notes, a high-profile default by another issuer, or a change in

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the market's psychology regarding high-yield notes. Moreover, if one of the major rating agencies were to lower its credit rating of the notes, the market price of the notes would likely decline.

         Our substantial levels of outstanding debt and letters of credit could adversely affect our financial condition and ability to fulfill our obligations.

        As of March 31, 2016, we and our guarantor subsidiaries had outstanding $1.65 billion aggregate principal amount of senior unsecured notes comprised of $800.0 million of 5.25% senior notes due 2020 and $845.0 million of 5.125% senior notes due 2021, no capital lease obligations, no revolving loans, and $145.2 million of letters of credit under our revolving credit facility. Our substantial levels of outstanding debt and letters of credit may:

        Our ability to make scheduled payments of principal or interest with respect to our debt, including the notes, any revolving loans and any future capital leases, and to pay fee obligations with respect to our letters of credit, will depend on our ability to generate cash and on our future financial results. Our ability to generate cash depends on, among other things, the demand for our services, which is subject to market conditions in the environmental, energy and industrial services industries, the occurrence of events requiring major remedial projects, changes in government environmental regulation, general economic conditions, and financial, competitive, regulatory and other factors affecting our operations, many of which are beyond our control. Our operations may not generate sufficient cash flow, and future borrowings may not be available under our revolving credit facility or otherwise, in an amount sufficient to enable us to pay our debt and fee obligations respecting our letters of credit, or to fund our other liquidity needs. If we were unable to generate sufficient cash flow from operations in the future to service our debt and letter of credit fee obligations, we might be required to refinance all or a portion of our existing debt and letter of credit facilities or to obtain new or additional such facilities. However, we might not be able to obtain any such new or additional facilities on favorable terms or at all.

         Despite our substantial levels of outstanding debt and letters of credit, we could incur substantially more debt and letter of credit obligations in the future.

        Although our revolving credit agreement and the indenture governing the notes contain restrictions on the incurrence of additional indebtedness (including, for this purpose, reimbursement obligations under outstanding letters of credit), these restrictions are subject to a number of qualifications and exceptions and the additional amount of indebtedness which we might incur in the future in compliance with these restrictions could be substantial. In particular, we had available at March 31, 2016, up to an additional approximately $156.4 million for purposes of additional borrowings and letters of credit. The

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indenture governing the notes also allows us to borrow significant amounts of money from other sources. These restrictions would also not prevent us from incurring obligations (such as operating leases) that do not constitute "indebtedness" as defined in the relevant agreements. To the extent we incur in the future additional debt and letter of credit obligations, the related risks will increase.

         The covenants in our debt agreements restrict our ability to operate our business and might lead to a default under our debt agreements.

        Our revolving credit agreement and the indenture governing our notes limit, among other things, our ability and the ability of our restricted subsidiaries to:

        As a result of these covenants, we may not be able to respond to changes in business and economic conditions and to obtain additional financing, if needed, and we may be prevented from engaging in transactions that might otherwise be beneficial to us. Our revolving credit facility requires, and our future credit facilities may require, us to maintain under certain circumstances specified financial ratios and satisfy certain financial condition tests. Our ability to meet these financial ratios and tests can be affected by events beyond our control, and we may not be able to meet those tests. The breach of any of these covenants could result in a default under our revolving credit facility or future credit facilities. Upon the occurrence of an event of default, the lenders could elect to declare all amounts outstanding under such credit facilities, including accrued interest or other obligations, to be immediately due and payable. If amounts outstanding under such credit facilities were to be accelerated, our assets might not be sufficient to repay in full that indebtedness and our other indebtedness, including the notes.

        Our revolving credit agreement and the indenture governing our notes also contain cross-default and cross-acceleration provisions. Under these provisions, a default or acceleration under one instrument governing our debt may constitute a default under our other debt instruments that contain cross-default or cross-acceleration provisions, which could result in the related debt and the debt issued under such other instruments becoming immediately due and payable. In such event, we would need to raise funds from alternative sources, which funds might not be available to us on favorable terms, on a timely basis or at all. Alternatively, such a default could require us to sell assets and otherwise curtail operations to pay our creditors. The proceeds of such a sale of assets, or curtailment of operations, might not enable us to pay all of our liabilities.

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         The notes are structurally subordinated to all debt of our subsidiaries that are not guarantors of the notes and may be effectively subordinated to certain of our and the guarantors' environmental liabilities.

        All of our domestic subsidiaries (other than domestic subsidiaries of our foreign subsidiaries) have guaranteed the notes, but our Canadian and other foreign subsidiaries are not guarantors. Furthermore, the guarantees of our domestic restricted subsidiaries are subject to customary release provisions under which, in particular, the guarantee of any of our domestic restricted subsidiaries will be released if we sell such subsidiary to an unrelated third party in accordance with the terms of the indenture which governs the notes. Noteholders will not have any claim as a creditor against our subsidiaries that are not guarantors of the notes. Accordingly, all obligations of our non-guarantor subsidiaries will have to be satisfied before any of the assets of such subsidiaries would be available for distribution, upon a liquidation or otherwise, to us or a guarantor of the notes. The indenture and our revolving credit facility allow us to incur substantial debt at our foreign subsidiaries, all of which would be structurally senior to the notes and the guaranties to the extent of the assets of those foreign subsidiaries. As of March 31, 2016, our non-guarantor subsidiaries had approximately $98.0 million of total liabilities (excluding intercompany liabilities and debt) and held approximately 23.6% of our total assets (excluding intercompany receivables and debt), and for the three months ended March 31, 2016, our non-guarantor subsidiaries generated approximately 20.8% of our consolidated revenues. Furthermore, in the event of a bankruptcy or similar proceeding relating to us or the guarantors, our and their existing and future environmental liabilities may effectively rank senior in right of payment to the notes and the guarantees under certain federal and state bankruptcy and environmental laws.

         Our obligation to repay the notes will be effectively junior to substantially all of our existing and future secured debt and the existing and future secured debt of our subsidiaries.

        The notes are unsecured obligations. The notes rank effectively junior in right of payment to our secured indebtedness, including indebtedness under our revolving credit facility, which is secured by liens on substantially all of our and our domestic subsidiaries' assets and the accounts receivable of our Canadian subsidiaries, and any of our future capital lease obligations. In the event of our bankruptcy, or the bankruptcy of our subsidiaries, holders of any of our or our subsidiaries' secured indebtedness will have claims that are prior to the claims of the noteholders to the extent of the value of the assets securing such secured debt. On March 31, 2016, we had no loans and $145.2 million of letters of credit outstanding under our revolving credit facility and no capital lease obligations. On March 31, 2016, we also had approximately $156.4 million of availability for additional loans and letters of credit under our revolving credit facility.

        If we defaulted on our obligations under any of our secured debt, our secured lenders could proceed against the collateral granted to them to secure that indebtedness. If any secured debt were to be accelerated, there can be no assurance that our assets would be sufficient to repay in full that indebtedness or our other debt, including the notes. In addition, upon any distribution of assets pursuant to any liquidation, insolvency, dissolution, reorganization or similar proceeding, the holders of secured indebtedness will be entitled to receive payment in full from the proceeds of the collateral securing our secured indebtedness before the holders of the notes will be entitled to receive any payment with respect thereto. As a result, the holders of the notes may recover proportionally less than the holders of secured indebtedness.

         A court could subordinate or void the obligations under our subsidiaries' guarantees.

        Under the U.S. federal bankruptcy laws and comparable provisions of state fraudulent conveyance laws, a court could void obligations under the guarantees by our subsidiaries, subordinate those

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obligations to other obligations of the Guarantors or require you to repay any payments made pursuant to the guarantees, if:

The measure of insolvency for these purposes will depend upon the law of the jurisdiction being applied. Generally, however, a company will be considered insolvent if:

Moreover, regardless of solvency, a court might void the guarantees, or subordinate the guarantees, if it determined that the transaction was made with intent to hinder, delay or defraud creditors.

        Each guarantee by our subsidiaries contains a provision intended to limit the Guarantor's liability to the maximum amount that it could incur without causing the incurrence of obligations under its guarantee to be a fraudulent transfer. This provision, however, may not be effective to protect the guarantees by our subsidiaries from attack under fraudulent transfer law or may reduce the Guarantor's obligations to an amount that effectively makes the subsidiary guarantee worthless. In a recent Florida bankruptcy case, this kind of provision was found ineffective to protect the guarantees. If one or more of the guarantees were voided or subordinated, after providing for all prior claims, there might not be sufficient assets remaining to satisfy the claims of the holders of the notes.

        The indenture requires that substantially all of our future domestic subsidiaries also must guarantee the notes in the future. These considerations will also apply to any such guarantees.

         We may not have the ability to repurchase the notes upon a change of control as required by the indenture.

        Upon the occurrence of a change of control (as defined in the indenture), the indenture requires us to offer to purchase all of the then outstanding notes at 101% of their principal amount plus accrued and unpaid interest to the date of repurchase. However, upon such a change of control, we may not have sufficient funds available to repurchase all of the notes tendered pursuant to this requirement. In addition, our revolving credit facility limits, and our future credit facilities may limit, our ability to repurchase any of the notes unless certain requirements are satisfied or the lenders thereunder consent. Our failure to repurchase the notes would be a default under the indenture, which would, in turn, be a default under our revolving credit facility and, potentially, other debt. If any debt were to be accelerated, we may be unable to repay these amounts and make the required repurchase of the notes. See "Description of the Notes—Certain Covenants—Change of Control."

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         The market valuation of the notes may be exposed to substantial volatility.

        A real or perceived economic downturn or higher interest rates could cause a decline in the market price of the notes and thereby negatively impact the market for the notes. Because the notes may be thinly traded, it may be more difficult to sell and accurately value the notes. In addition, as has recently been evident in the global financial markets, the economic slowdown and the uncertainty over its breadth, depth and duration, the entire high-yield bond market can experience sudden and sharp price swings, which can be exacerbated by large or sustained sales by major investors in the notes, a high-profile default by another issuer, or a change in the market's psychology regarding high-yield notes. Moreover, if one of the major rating corporations were to lower its credit rating of the notes, the market price of the notes would likely decline.

Risks Affecting All of Our Businesses

         Our businesses are subject to operational and safety risks.

        Provision of environmental, energy and industrial services to our customers by all six of our business segments involves risks such as equipment defects, malfunctions and failures, and natural disasters, which could potentially result in releases of hazardous materials, injury or death of our employees, or a need to shut down or reduce operation of our facilities while remedial actions are undertaken. Our employees often work under potentially hazardous conditions. These risks expose us to potential liability for pollution and other environmental damages, personal injury, loss of life, business interruption, and property damage or destruction. We must also maintain a solid safety record in order to remain a preferred supplier to our major customers.

        While we seek to minimize our exposure to such risks through comprehensive training programs, vehicle and equipment maintenance programs, and insurance, such programs and insurance may not be adequate to cover all of our potential liabilities and such insurance may not in the future be available at commercially reasonable rates. If we were to incur substantial liabilities in excess of policy limits or at a time when we were not able to obtain adequate liability insurance on commercially reasonable terms, our business, results of operations and financial condition could be adversely affected to a material extent. Furthermore, should our safety record deteriorate, we could be subject to a potential reduction of revenues from our major customers.

         Our businesses are subject to numerous statutory and regulatory requirements, which may increase in the future.

        Our businesses are subject to numerous statutory and regulatory requirements, and our ability to continue to hold licenses and permits required for our businesses is subject to maintaining satisfactory compliance with such requirements. These requirements may increase in the future as a result of statutory and regulatory changes. Although we are very committed to compliance and safety, we may not, either now or in the future, be in full compliance at all times with such statutory and regulatory requirements. Consequently, we could be required to incur significant costs to maintain or improve our compliance with such requirements.

         Certain adverse conditions have required, and future conditions might require, us to make substantial write-downs in our assets, which have adversely affected or would adversely affect our balance sheet and results of operations.

        We review our long-lived tangible and intangible assets for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. We also test our goodwill and indefinite-lived intangible assets for impairment at least annually on December 31, or when events or changes in the business environment indicate that the carrying value of a reporting unit may exceed its fair value. Based on the results of those tests, we determined during the second quarter

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of 2015 that the then carrying amount of our Oil and Gas Field Services reporting unit exceeded the estimated fair value of that unit and we therefore then recognized a goodwill impairment charge of $32.0 million with respect to that unit. During the third quarter of 2014, we determined that the then carrying amount of our Kleen Performance Products reporting unit exceeded the estimated fair value of that unit and we therefore then recognized a goodwill impairment charge of $123.4 million with respect to that unit. During and as of the end of each of 2015 and 2014, we determined that no other asset write-downs were required. However, if conditions in any of the businesses in which we compete were to deteriorate, we could determine that certain of our assets were impaired and we would then be required to write-off all or a portion of our costs for such assets. Any such significant write-offs would adversely affect our balance sheet and results of operations.

         Fluctuations in foreign currency exchange could affect our financial results.

        We earn revenues, pay expenses, own assets and incur liabilities in countries using currencies other than the U.S. dollar. In fiscal 2015, we recorded 21% of our revenues outside of the United States, primarily in Canada. Because our consolidated financial statements are presented in U.S. dollars, we must translate revenues, income and expenses as well as assets and liabilities into U.S. dollars at exchange rates in effect during or at the end of each reporting period. Therefore, increases or decreases in the value of the U.S. dollar against other currencies in countries where we operate will affect our results of operations and the value of balance sheet items denominated in foreign currencies. These risks are non-cash exposures, and we manage these risks through normal operating and financing activities. However, we may not be successful in reducing the risks inherent in exposures to foreign currency fluctuations.

         Failure to effectively manage acquisitions and divestitures could adversely impact our future results.

        We continuously evaluate potential acquisition candidates and from time to time acquire companies that we believe will strategically fit into our business and growth objectives. In particular, we acquired on December 28, 2012, all of the outstanding shares of Safety-Kleen for approximately $1.26 billion in cash, on September 13, 2013, all of the outstanding shares of Evergreen Oil, Inc. for approximately $56.3 million in cash, on April 11, 2015, all of the outstanding shares of Thermo Fluids Inc. for approximately $79.3 million in cash, on February 3, 2016, a re-refinery facility in Nevada for $35.0 million in cash, subject to customary post-closing adjustments. Additional less significant acquisitions have also been completed in recent years. If we are unable to successfully integrate and develop acquired businesses, we could fail to achieve anticipated synergies and cost savings, including any expected increases in revenues and operating results, which could have a material adverse effect on our financial results.

        We also continually review our portfolio of assets to determine the extent to which they are contributing to our objectives and growth strategy. In particular, on January 20, 2015, we announced a planned carve-out to include our Oil and Gas Field Service segment and the drilling-related mobile assets of our Lodging Services segment, subject to certain conditions, and on May 6, 2015, we announced the expansion of the planned carve-out to include our entire Lodging Services segment, subject to certain conditions. However, we may not be successful in separating underperforming or non-strategic assets, and gains or losses on the divestiture of, or lost operating income from, such assets may adversely affect our earnings. Moreover, we may incur asset impairment charges related to acquisitions or divestitures that reduce our earnings.

         Our acquisitions may expose us to unknown liabilities.

        Because we have acquired, and expect generally to acquire, all the outstanding shares of most of our acquired companies, our investment in those companies are or will be subject to all of their liabilities other than their respective debts which we paid or will pay at the time of the acquisitions. If

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there are unknown liabilities or other obligations, our business could be materially affected. We may also experience issues relating to internal controls over financial reporting, issues that could affect our ability to comply with the Sarbanes-Oxley Act, or issues that could affect our ability to comply with other applicable laws.

         A cyber security incident could negatively impact our business and our relationships with customers.

        We use computers in substantially all aspects of our business operations and also mobile devices and other online activities to connect with our employees and customers. Such uses give rise to cyber security risks, including security breach, espionage, system disruption, theft and inadvertent release of information. Our business involves the storage and transmission of numerous classes of sensitive and/or confidential information and intellectual property including, but not limited to, private information about employees, and financial and strategic information about our Company and our business partners. Furthermore, as we pursue our strategy to grow through acquisitions and new initiatives that improve our operations and cost structure, we are also expanding and improving our information technologies, resulting in a larger technological presence and corresponding exposure to cyber security risk. If we fail to assess and identify cyber security risks associated with acquisitions and new initiatives, we may become increasingly vulnerable to such risks. Additionally, while we have implemented measures to prevent security breaches and cyber incidents, our preventative measures and incident response efforts may not be entirely effective. The theft, destruction, loss, misappropriation, or release of sensitive and/or confidential information or intellectual property, or interference with our information technology systems or the technology systems of third parties on which we rely, could result in business disruption, negative publicity, brand damage, violation of privacy laws, loss of customers, potential liability and competitive disadvantage.

Additional Risks of Our Technical Services Business

         The hazardous waste management business conducted by our Technical Services segment is subject to significant environmental liabilities.

        We have accrued environmental liabilities valued as of March 31, 2016, at $189.5 million, substantially all of which we assumed in connection with certain acquisitions. We calculate our environmental liabilities on a present value basis in accordance with generally accepted accounting principles, which take into consideration both the amount of such liabilities and the timing when it is projected that we will be required to pay such liabilities. We anticipate our environmental liabilities will be payable over many years and that cash flows generated from our operations will generally be sufficient to fund the payment of such liabilities when required. However, events not now anticipated (such as future changes in environmental laws and regulations or their enforcement) could require that such payments be made earlier or in greater amounts than now estimated, which could adversely affect our financial condition and results of operations.

        We may also assume additional environmental liabilities as part of further acquisitions. Although we will endeavor to accurately estimate and limit environmental liabilities presented by the businesses or facilities to be acquired, some liabilities, including ones that may exist only because of the past operations of an acquired business or facility, may prove to be more difficult or costly to address than we then estimate. It is also possible that government officials responsible for enforcing environmental laws may believe an environmental liability is more significant than we then estimate, or that we will fail to identify or fully appreciate an existing liability before we become legally responsible to address it.

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         If we become unable to obtain at reasonable cost the insurance, surety bonds, letters of credit and other forms of financial assurance required for our facilities and operations, our business and results of operations would be adversely affected.

        We are required to provide substantial amounts of financial assurance to governmental agencies for closure and post-closure care of our licensed hazardous waste treatment facilities should those facilities cease operation, and we are also occasionally required to post surety, bid and performance bonds in connection with certain projects. As of March 31, 2016, our total estimated closure and post-closure costs requiring financial assurance by regulators were $431.6 million for our U.S. facilities and $39.5 million for our Canadian facilities. We have obtained all of the required financial assurance for our facilities through a combination of surety bonds, funded trusts, letters of credit and insurance from a qualified insurance company. The financial assurance related to closure and post-closure obligations of our U.S. facilities will renew in 2016. Our Canadian facilities utilize surety bonds, which renew at various dates throughout 2016, as well as letters of credit. In connection with obtaining such insurance and surety bonds, we have provided our insurance companies $82.1 million of letters of credit which we obtained under our revolving credit agreement.

        Our ability to continue operating our facilities and conducting our other operations would be adversely affected if we became unable to obtain sufficient insurance, surety bonds, letters of credit and other forms of financial assurance at reasonable cost to meet our regulatory and other business requirements. The availability of insurance, surety bonds, letters of credit and other forms of financial assurance is affected by our insurers', sureties' and lenders' assessment of our risk and by other factors outside of our control such as general conditions in the insurance and credit markets.

         The hazardous waste management industry in which we participate is subject to significant economic and business risks.

        The future operating results of our Technical Services segment may be affected by such factors as our ability to utilize our facilities and workforce profitably in the face of intense price competition, maintain or increase market share in an industry which has in the past experienced significant downsizing and consolidation, realize benefits from cost reduction programs, invest in new technologies for treatment of hazardous waste, generate incremental volumes of waste to be handled through our facilities from existing and acquired sales offices and service centers, obtain sufficient volumes of waste at prices which produce revenue sufficient to offset the operating costs of our facilities, minimize downtime and disruptions of operations, and develop our field services business. In particular, economic downturns or recessionary conditions in North America, and increased outsourcing by North American manufacturers to plants located in countries with lower wage costs and less stringent environmental regulations, have adversely affected and may in the future adversely affect the demand for our services. Our Technical Services segment is also cyclical to the extent that it is dependent upon a stream of waste from cyclical industries such as chemical and petrochemical, primary metals, paper, furniture and aerospace. If those cyclical industries slow significantly, the business that we receive from them would likely decrease.

         The extensive environmental regulations to which we are subject may increase our costs and potential liabilities and limit our ability to expand our facilities.

        Our operations and those of others in the environmental services industry are subject to extensive federal, state, provincial and local environmental requirements in both the United States and Canada, including those relating to emissions to air, discharged wastewater, storage, treatment, transport and disposal of regulated materials, and cleanup of soil and groundwater contamination. For example, any failure to comply with governmental regulations governing the transport of hazardous materials could negatively impact our ability to collect, process and ultimately dispose of hazardous wastes generated by our customers. While increasing environmental regulation often presents new business opportunities for

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us, it often also results in increased operating and compliance costs. Efforts to conduct our operations in compliance with all applicable laws and regulations, including environmental rules and regulations, require programs to promote compliance, such as training employees and customers, purchasing health and safety equipment, and in some cases hiring outside consultants and lawyers. Even with these programs, we and other companies in the environmental services industry are routinely faced with governmental enforcement proceedings, which can result in fines or other sanctions and require expenditures for remedial work on waste management facilities and contaminated sites. Certain of these laws impose strict and, under certain circumstances, joint and several liability on current and former owners and operators of facilities that release regulated materials or that generate those materials and arrange for their disposal or treatment at contaminated sites. Such liabilities can relate to required cleanup of releases of regulated materials and related natural resource damages.

        From time to time, we have paid fines or penalties in governmental environmental enforcement proceedings, usually involving our waste treatment, storage and disposal facilities. Although none of these fines or penalties that we have paid in the past has had a material adverse effect upon us, we might in the future be required to make substantial expenditures as a result of governmental proceedings which would have a negative impact on our earnings. Furthermore, regulators have the power to suspend or revoke permits or licenses needed for operation of our plants, equipment, and vehicles based on, among other factors, our compliance record, and customers may decide not to use a particular disposal facility or do business with us because of concerns about our compliance record. Suspension or revocation of permits or licenses would impact our operations and could have a material impact on our financial results. Although we have never had any of our facilities' operating permits revoked, suspended or non-renewed involuntarily, it is possible that such an event could occur in the future.

        Some environmental laws and regulations impose liability and responsibility on present and former owners, operators or users of facilities and sites for contamination at such facilities and sites without regard to causation or knowledge of contamination. In the past, practices have resulted in releases of regulated materials at and from certain of our facilities, or the disposal of regulated materials at third party sites, which may require investigation and remediation, and potentially result in claims of personal injury, property damage and damages to natural resources. In addition, we occasionally evaluate various alternatives with respect to our facilities, including possible dispositions or closures. Investigations undertaken in connection with these activities may lead to discoveries of contamination that must be remediated, and closures of facilities might trigger compliance requirements that are not applicable to operating facilities. We are currently conducting remedial activities at certain of our facilities and paying a portion of the remediation costs at certain sites owned by third parties. While, based on available information, we do not believe these remedial activities will result in a material effect upon our operations or financial condition, these activities or the discovery of previously unknown conditions could result in material costs.

        In addition to the costs of complying with environmental laws and regulations, we incur costs defending against environmental litigation brought by governmental agencies and private parties. We are now, and may in the future be, a defendant in lawsuits brought by parties alleging environmental damage, personal injury, and/or property damage, which may result in our payment of significant amounts of liabilities.

        Environmental and land use laws also impact our ability to expand our facilities. In addition, we are required to obtain governmental permits to operate our facilities, including all of our landfills. Even if we comply with all applicable environmental laws, we might not be able to obtain requisite permits from applicable governmental authorities to extend or modify such permits to fit our business needs.

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         If our assumptions relating to expansion of our landfills should prove inaccurate, our results of operations and cash flow could be adversely affected.

        When we include expansion airspace in our calculation of available airspace, we adjust our landfill liabilities to the present value of projected costs for cell closure and landfill closure and post-closure. It is possible that our estimates or assumptions could ultimately turn out to be significantly different from actual results. In some cases we may be unsuccessful in obtaining an expansion permit or we may determine that an expansion permit that we previously thought was probable has become unlikely. To the extent that such estimates, or the assumptions used to make those estimates, prove to be significantly different than actual results, or our belief that we will receive an expansion permit changes adversely in a significant manner, the landfill assets, including the assets incurred in the pursuit of the expansion, may be subject to impairment testing and lower prospective profitability may result due to increased interest accretion and depreciation or asset impairments related to the removal of previously included expansion airspace. In addition, if our assumptions concerning expansion airspace should prove inaccurate, certain of our cash expenditures for closure of landfills could be accelerated and adversely affect our results of operations and cash flow.

Additional Risks of Our Industrial and Field Services Business

         A significant portion of our Industrial and Field Services business depends upon the demand for cleanup of major spills and other remedial projects and regulatory developments over which we have no control.

        Our operations can be affected by the commencement and completion of cleanup of major spills and other events, customers' decisions to undertake remedial projects, seasonal fluctuations due to weather and budgetary cycles influencing the timing of customers' spending for remedial activities, the timing of regulatory decisions relating to hazardous waste management projects, changes in regulations governing the management of hazardous waste, secular changes in the waste processing industry towards waste minimization and the propensity for delays in the demand for remedial services, and changes in the myriad of governmental regulations governing our diverse operations. We do not control such factors and, as a result, our revenue and income can vary from quarter to quarter, and past financial performance for certain quarters may not be a reliable indicator of future performance for comparable quarters in subsequent years.

Additional Risks of Our Kleen Performance Products Business

         Fluctuations in oil prices may have a negative effect on our Kleen Performance Products business.

        A significant portion of our business involves collecting used oil from certain of our customers, re-refining a portion of such used oil into base and blended lubricating oils, and then selling both such re-refined oil and the excess recycled oil which we do not currently have the capacity to re-refine, or "RFO," to other customers. The prices at which we sell our re-refined oil and RFO are affected by changes in the reported spot market prices of oil. If applicable rates increase or decrease, we typically will charge a higher or lower corresponding price for our re-refined oil and RFO. The price at which we sell our re-refined oil and RFO is affected by changes in certain indices measuring changes in the price of heavy fuel oil, with increases and decreases in the indices typically translating into a higher or lower price for our RFO. The cost to collect used oil, including the amounts we pay to obtain a portion of our used oil and therefore ability to collect necessary volumes as well as the fuel costs of our oil collection fleet, typically also increases or decreases when the relevant indices increase or decrease. However, even though the prices we can charge for our re-refined oil and RFO and the costs to collect and re-refine used oil and process RFO typically increase and decrease together, there is no assurance that when our costs to collect and re-refine used oil and process RFO increase we will be able to increase the prices we charge for our re-refined oil and RFO to cover such increased costs, or that our costs to collect and re-refine used oil and process RFO will decline when the prices we can charge for

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re-refined oil and RFO decline. These risks are exacerbated when there are rapid fluctuations in these oil indices.

Additional Risks of Our SK Environmental Services Business

         Environmental laws and regulations have adversely affected and may adversely affect Safety-Kleen's parts cleaning and other solvent related services.

        In connection with its parts cleaning and other solvent related services, Safety-Kleen has been subject to fines and certain orders requiring it to take environmental remedial action. Safety-Kleen may be subject to monetary fines, civil or criminal penalties, remediation, cleanup or stop orders, injunctions, orders to cease or suspend certain practices or denial of permits required for the operation of its facilities. The outcome of any proceeding and associated costs and expenses could have a material adverse impact on Safety-Kleen's financial condition and results of operations.

        Recent and potential changes in environmental laws and regulations may also adversely affect in the future Safety-Kleen's parts cleaning and other solvent related services. Interpretation or enforcement of existing laws and regulations, or the adoption of new laws and regulations, may require Safety-Kleen to modify or curtail its operations or replace or upgrade its facilities or equipment at substantial cost, which we may not be able to pass on to our customers, and we may choose to indemnify our customers from any fines or penalties they may incur as a result of these new laws and regulations. On the other hand, in some cases if new laws and regulations are less stringent, Safety-Kleen's customers or competitors may be able to manage waste more effectively themselves, which could decrease the need for Safety-Kleen's services or increase competition, which could adversely affect Safety-Kleen's results of operations.

         Safety-Kleen is subject to existing and potential product liability lawsuits.

        Safety-Kleen has been named from time to time as a defendant in various product liability lawsuits in various courts and jurisdictions throughout the United States. As of March 31, 2016, Safety-Kleen was involved in approximately 60 proceedings (including cases which have been settled but not formally dismissed) wherein persons claim personal injury resulting from the use of its parts cleaning equipment or cleaning products. These proceedings typically involve allegations that the solvent used in Safety-Kleen's parts cleaning equipment contains contaminants or that Safety-Kleen's recycling process does not effectively remove the contaminants that become entrained in the solvent during their use. In addition, certain claimants assert that Safety-Kleen failed to warn adequately the product user of potential risks, including a historic failure to warn that solvent contains trace amounts of toxic or hazardous substances such as benzene. Although Safety-Kleen maintains insurance that we believe will provide coverage for these claims (over amounts accrued for self-insured retentions and deductibles in certain limited cases), this insurance may not provide coverage for potential awards of punitive damages against Safety-Kleen. Although Safety-Kleen has vigorously defended and will continue to vigorously defend itself and the safety of its products against all of these claims, these matters are subject to many uncertainties and outcomes are not predictable with assurance. Safety-Kleen may also be named in similar, additional lawsuits in the future, including claims for which insurance coverage may not be available. If one or more of these claims were decided unfavorably against Safety-Kleen and the plaintiffs were awarded punitive damages, or if insurance coverage were not available for any such claim, our financial condition and results of operations could be materially and adversely affected. Additionally, if one or more of these claims were decided unfavorably against Safety-Kleen, such outcome may encourage more lawsuits against us.

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         Safety-Kleen is dependent on third parties for the manufacturing of the majority of its equipment.

        Safety-Kleen does not manufacture the majority of the equipment, including parts washers, that Safety-Kleen places at customer sites. Accordingly, Safety-Kleen relies on a limited number of third party suppliers for manufacturing this equipment. The supply of third party equipment could be interrupted or halted by a termination of Safety-Kleen's relationships, a failure of quality control or other operational problems at such suppliers or a significant decline in their financial condition. If Safety-Kleen were not able to retain these providers or obtain its requests from them, Safety-Kleen may not be able to obtain alternate providers in a timely manner or on economically attractive terms, and as a result, Safety-Kleen may not be able to compete successfully for new business, complete existing engagements profitably or retain its existing customers. Additionally, if Safety-Kleen's third party suppliers provide it with defective equipment, it may be subject to reputational damage or product liability claims which may negatively impact its reputation, financial condition and results of operations. Further, Safety-Kleen generally does not have long-term contracts with its third party suppliers, and as a result these suppliers may increase the price of the equipment they provide to Safety-Kleen, which may hurt Safety-Kleen's results of operations.

Additional Risks of Our Lodging Services Business

         All of our major Canadian lodges are located on land subject to leases; if we were unable to renew a lease, we could be materially and adversely affected.

        All of our major Canadian lodges are located on land subject to leases. Accordingly, while we own the accommodations assets and can move them to other locations, if necessary, we only own a leasehold in those properties. If we were found to be in breach of a lease, we could lose the right to use the property. In addition, unless we could extend the terms of these leases before their expiration, we would lose our right to operate our facilities located on these properties upon expiration of the leases. In that event, we would be required to remove our accommodations assets and remediate the sites. We may not be able to renew our leases upon expiration on similar terms, or at all, and if we were unable to renew leases on similar terms, it may have an adverse effect on our business. In addition, if we were to lose the right to use a lodge due to non-renewal of a lease, we would be unable to derive income from such lodge, which could materially and adversely affect us.

         Due to the significant concentration of our Lodging Services business in the oil sands region of Alberta, Canada, adverse events in that region could negatively impact our business.

        Because of the concentration of our accommodations business in the oil sands region of Alberta, Canada, we have increased exposure to political, economic, regulatory, environmental, labor, climate or natural disaster events or developments that could disproportionately impact our operations and financial results.

         Our Lodging Services business depends significantly on several major customers, and the loss of one or more such customers or the inability of one or more such customers to meet their obligations to us could adversely affect our results of operations.

        Our Lodging Services business depends significantly on several major customers engaged primarily in oil and gas exploration and production. Declines in the general level of oil and gas exploration and production in the oil sands region resulting in decreased demand in our lodging services have occurred in recent periods and could occur in the future, and have had and could have in the future adverse effects on the revenues and profitability of our Lodging Services business. The loss of any one or more of such large customers or a sustained decrease in demand by any of them have resulted and could result in a substantial loss of revenues and have had and could have a material adverse effect on our results of operations. In addition, the concentration of our customers in oil and gas exploration and

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production may impact our overall exposure to credit risk, either positively or negatively, because our customers may be similarly affected by changes in economic and industry conditions. While we perform ongoing credit evaluations of our customers, we do not generally require collateral in support of our trade receivables. As a result, we are subject to risks of loss resulting from nonpayment or nonperformance by our customers.

         We may be adversely affected if customers reduce their accommodations outsourcing.

        The business and growth strategy of our Lodging Services business depends in large part on the continuation of a current trend toward outsourcing services. Many oil and gas companies in our core markets own their own accommodations facilities, while others outsource all or part of their accommodations requirements. Customers have largely built their accommodations in the past but will outsource if they perceive that outsourcing may provide quality services at a lower overall cost or allow them to accelerate the timing of their projects. We cannot be certain that this trend will continue and not be reversed or that customers that have outsourced accommodations will not decide to perform these functions themselves or only outsource accommodations during the development or construction phases of their projects. In addition, labor unions representing customer employees and contractors have, in the past, opposed outsourcing accommodations to the extent that the unions believe that third-party accommodations negatively impact union membership and recruiting. The reversal or reduction in customer outsourcing of accommodations could negatively impact our financial results and growth prospects.

         Increased operating costs and obstacles to cost recovery due to the pricing and cancellation terms of our accommodation services contracts may constrain our ability to make a profit.

        The profitability of our Lodging Services business can be adversely affected by cost increases for food, wages and other labor related expenses, insurance, fuel and utilities, especially to the extent we are unable to recover such increased costs through increases in the prices for our services due to general economic conditions, competitive conditions or contractual provisions in our customer contracts. Oil and natural gas prices have fluctuated significantly in the last several years, and substantial increases in the cost of fuel and utilities have historically resulted in cost increases for our lodges. From time to time we have also experienced increases in our food costs. While we believe a portion of these increases were attributable to fuel prices, we believe the increases also resulted from rising global food demand. In addition, food prices can fluctuate as a result of temporary changes in supply, including as a result of severe weather such as droughts, heavy rains and late freezes. While our long term contracts often provide for annual escalation in our room rates for food, labor and utility inflation, we may be unable to fully recover costs and such increases in costs would negatively impact our profitability on contracts that do not contain inflation protections.

Additional Risks of Our Oil and Gas Field Services Business

         A large portion of our Oil and Gas Field Services business is dependent on the oil and gas industry in Western Canada, and declines in oil and gas exploration and production in that region have adversely affected and could in the future adversely affect our business.

        Our Oil and Gas Field Services business generates a significant portion of its total revenues from customers in the oil and gas industry operating in Western Canada, although a majority of the services we provide to such customers relate to oil and gas production and refining which is less volatile than oil and gas exploration. Accordingly, declines in the general level of oil and gas exploration and production in Western Canada have had and could potentially have significant adverse effects on the revenues and profitability of our Oil and Gas Field Services business and have resulted and could also potentially result in asset impairment charges being recognized, including the goodwill impairment charge of $32.0 million we recognized with respect to our Oil and Gas Field Services reporting unit

23


during the third quarter of 2015. Such declines have occurred and could potentially occur in the future if reductions in the commodity prices of oil and gas result in reduced oil and gas exploration, production and refining. Such declines could also be triggered by technological and regulatory changes, such as those affecting the availability and cost of alternative energy sources and other changes in industry and worldwide economic and political conditions.

        Many of our major customers in the oil and gas industry conduct a significant portion of their operations in the Alberta oil sands. The Alberta oil sands contain large oil deposits, but extraction may involve significantly greater cost and environmental concerns than conventional drilling. While we believe our major involvement in the oil sands region will provide significant future growth opportunities, such involvement also increases the risk that our business will be adversely affected if future economic activity in the Alberta oil sands were to further decline. Major factors that could cause such a decline might include a prolonged reduction in the commodity price of oil, future changes in environmental restrictions and regulations, and technological and regulatory changes relating to production of oil from the oil sands. The downturn in worldwide economic conditions and in the commodity price of oil and gas which has recently occurred and continues to occur has caused certain of our customers to delay a number of large projects in the planning and early development phases within the oil sands region. In addition, customers are revisiting their operating budgets and challenging their suppliers to reduce costs and achieve better efficiencies in their work programs.

         Although we plan to carve-out our Oil and Gas Field Services and Lodging Services segments into a stand-alone new public company, there is no assurance if and when such carve-out will occur. Furthermore, even if and when such carve-out does occur, we will remain subject to the risks now associated with our Oil and Gas Field Services and Lodging Services segments as long as we retain a significant ownership interest in such new public company.

        On January 20, 2015, we announced that we plan to carve out primarily our Oil and Gas Field Services segment and our lodging drill camps business from our Lodging Services segment into a new standalone public company. On May 6, 2015, we expanded the planned carve-out to include our entire Lodging Services segment as part of that new company. Completion of the carve-out is subject to certain conditions including, but not limited to, market conditions, determination of the most advantageous structure from a financial and tax standpoint, overall costs to our Company, receipt of regulatory approvals, compliance with our debt covenants, the effectiveness of securities laws filings and final approval by our board of directors. There can be no assurance regarding the ultimate structure and timing of the proposed transaction or whether the transaction will be completed. Furthermore, even if and when such carve-out does occur, we will remain subject to the risks now associated with our Oil and Gas Field Services and Lodging Services segments as long as we retain a significant ownership interest in the new public company.

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USE OF PROCEEDS

        We will not receive any proceeds from the exchange offer. In consideration for issuing the new notes, we will receive old notes from you in like principal amount. The old notes surrendered in exchange for the new notes will be retired and canceled and cannot be reissued. Accordingly, issuance of the new notes will not result in any change in our indebtedness.


RATIO OF EARNINGS TO FIXED CHARGES

        The following table sets forth our consolidated ratios of earnings to fixed charges for the periods shown.

 
  Three
Months
Ended
March 31,
  Year Ended December 31,  
 
  2016   2015   2015   2014   2013   2012   2011  

Ratio of earnings to fixed charges(1)(2)

    0.8x     1.3x     2.2x     1.4x     2.6x     3.3x     5.0x  

(1)
For purposes of calculating the earnings to fixed charges, earnings consist of income from operations before income tax plus fixed charges. Fixed charges consist of interest expense, including capitalized interest, amortization of debt issuance costs and a portion of the operating lease rental expense deemed to be representative of the interest factor. For the three months ended March 31, 2016, the ratio of earnings to fixed charges was less than 1.0x, and fixed charges exceeded earnings by approximately $4.9 million.

(2)
Our 2015 income from operations before income tax was reduced by a $32.0 million goodwill impairment charge in our Oil and Gas Field Services reporting unit, and our 2014 income from operations before income tax was reduced by a $123.4 million goodwill impairment charge in our Kleen Performance Products reporting unit. See Note 6, "Goodwill and Other Intangible Assets," to our consolidated financial statements as of December 31, 2015 and 2014, and for each of the three years in the period ended December 31, 2015, incorporated by reference in this prospectus for additional information regarding those goodwill impairment charges. Our 2012 income from operations before income tax was reduced by a $26.4 million loss on early extinguishment of debt in connection with a redemption and repurchase of our $520.0 million previously outstanding 75/8% senior secured notes.

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CAPITALIZATION

        The Company will not be receiving any additional cash proceeds as a result of this exchange offer. The following table sets forth our consolidated cash and cash equivalents, long-term obligations (including current portion), and stockholders' equity as of March 31, 2016. This table should be read in conjunction with "Use of Proceeds," "Selected Historical Consolidated Financial Information," and "Description of Other Indebtedness" appearing elsewhere in this prospectus and our historical financial statements and the notes thereto incorporated by reference in this prospectus.

 
  March 31, 2016  
 
  (in thousands)
 

Cash and cash equivalents

  $ 355,345  

Long-term debt, including current portion:

       

Revolving credit facility(1)(2)

  $  

Capital lease obligations

     

5.25% senior unsecured notes due 2020(3)

    800,000  

5.125% senior unsecured notes due 2021(3)

    845,000  

Unamortized debt issuance costs(4)

    (13,397 )

Total long-term obligations, including current portion(2)

    1,631,603  

Stockholders' equity:

       

Common stock, $.01 par value;

       

Authorized 80,000,000 shares; issued and outstanding 57,551,188 shares

    576  

Shares held under employee participation plan

    (469 )

Additional paid-in capital

    733,726  

Accumulated other comprehensive loss

    (209,055 )

Accumulated earnings

    591,795  

Total stockholders' equity

    1,116,573  

Total capitalization

  $ 2,748,176  

(1)
We have a revolving credit facility secured by a lien on substantially all of the assets of Clean Harbors, Inc. and its domestic subsidiaries and the accounts receivable of its Canadian subsidiaries under which we and our domestic subsidiaries have the right to borrow and obtain letters of credit for a combined maximum of up to $300.0 million (with a sub-limit of $250.0 million for letters of credit) and our Canadian subsidiaries have a right to borrow and obtain letters of credit for a combined maximum of up to $100.0 million (with a sub-limit of $75.0 million for letters of credit).

(2)
Amounts under our revolving credit facility and total long-term obligations exclude $145.2 million of letters of credit outstanding on March 31, 2016 under our revolving credit facility.

(3)
Includes the principal amount of the notes, prior to deduction of the initial purchaser's discount and other offering costs.

(4)
Unamortized debt issuance costs include the initial purchaser's discount and other offering costs.

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SELECTED HISTORICAL CONSOLIDATED FINANCIAL INFORMATION

        The following selected historical consolidated financial information has been derived from our audited consolidated balance sheets at December 31, 2015 and 2014 and consolidated statements of income (loss) and cash flows for the three years ended December 31, 2015, and our unaudited balance sheet at March 31, 2016 and statements of operations and cash flows for the three months ended March 31, 2016 and 2015. This data should be reviewed in conjunction with "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our audited and unaudited historical financial statements and the notes thereto incorporated by reference in this prospectus. We have derived the income and cash flow information for the two years ended December 31, 2012 and December 31, 2011 and the December 31, 2013, 2012 and 2011 balance sheet information from our audited historical financial statements not included or incorporated herein.

 
  Three Months Ended
March 31,
  Year Ended December 31,  
 
  2016   2015   2015   2014   2013   2012   2011  

Income Statement Data:

                                           

Revenues

  $ 636,083   $ 732,499   $ 3,275,137   $ 3,401,636   $ 3,509,656     2,187,908   $ 1,984,136  

Cost of revenues (exclusive of items shown separately below)

    464,279     546,507     2,356,806     2,441,796     2,542,633     1,540,621     1,379,991  

Selling, general and administrative expenses

    104,484     107,715     414,164     437,921     470,477     273,520     254,137  

Accretion of environmental liabilities

    2,505     2,619     10,402     10,612     11,541     9,917     9,680  

Depreciation and amortization

    68,902     68,356     274,194     276,083     264,449     161,646     122,663  

Goodwill impairment charge(1)

            31,992     123,414              

(Loss) income from operations

    (4,087 )   7,302     187,579     111,810     220,556     202,204     217,665  

Other (expense) income

    (350 )   409     (1,380 )   4,380     1,705     (802 )   6,402  

Loss on early extinguishment of debt(1)

                        (26,385 )    

Interest expense, net

    (18,980 )   (19,438 )   (76,553 )   (77,668 )   (78,376 )   (47,287 )   (39,389 )

(Loss) income before (benefit from) provision for income taxes

    (23,417 )   (11,727 )   109,646     38,522     143,885     127,730     184,678  

(Benefit from) provision for income taxes(1)

    (2,546 )   (4,638 )   65,544     66,850     48,319     (1,944 )   57,426  

Net (loss) income

  $ (20,871 ) $ (7,089 ) $ 44,102   $ (28,328 ) $ 95,566   $ 129,674   $ 127,252  

(Loss) earnings per share:(1)(2)

                                           

Basic

  $ (0.36 ) $ (0.12 ) $ 0.76     (0.47 ) $ 1.58   $ 2.41   $ 2.40  

Diluted

  $ (0.36 ) $ (0.l2 ) $ 0.76     (0.47 ) $ 1.57   $ 2.40   $ 2.39  

Cash Flow Data:

                                           

Net cash from operating activities

  $ 39,289   $ 84,777   $ 396,383   $ 297,366   $ 415,839   $ 324,365   $ 179,531  

Net cash used in investing activities

    (110,013 )   (53,360 )   (350,642 )   (258,294 )   (345,512 )   (1,572,636 )   (480,181 )

Net cash from (used in) financing activities

    236,794     (37,194 )   (90,179 )   (93,945 )   13,126     1,217,868     258,740  

Other Financial Data:

   
 
   
 
   
 
   
 
   
 
   
 
   
 
 

Adjusted EBITDA(3)

  $ 67,320   $ 78,277   $ 504,167   $ 521,919   $ 510,105   $ 373,767   $ 350,008  

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  At December 31,  
 
  At March 31,
2016
 
 
  2015   2014   2013   2012   2011  

Balance Sheet Data:

                                     

Working capital

  $ 598,111   $ 404,076   $ 553,962   $ 531,634   $ 506,593   $ 510,126  

Goodwill

    460,642     453,105     452,669     570,960     579,715     122,392  

Total assets

    3,641,675     3,431,428     3,689,423     3,936,430     3,819,338     2,076,089  

Long-term obligations (including current portion)(4)

    1,631,603     1,382,543     1,380,681     1,385,516     1,389,223     529,174  

Stockholders' equity

    1,116,573     1,096,282     1,262,871     1,475,639     1,432,072     900,987  

(1)
The 2015 results include a $32.0 million goodwill impairment charge in our Oil and Gas Field Services reporting unit and the 2014 results include a $123.4 million goodwill impairment charge in our Kleen Performance Products reporting unit. In 2015 and 2014, we recorded an income tax benefit of $2.0 million and $2.7 million, respectively, as a result of the goodwill impairment charge. See Note 6, "Goodwill and Other Intangible Assets," to our consolidated financial statements incorporated by reference in this prospectus for additional information regarding those goodwill impairment charges. The 2012 results include a $26.4 million loss on early extinguishment of debt in connection with a redemption and repurchase of our $520.0 million previously outstanding senior secured notes and a benefit for income taxes of $1.9 million primarily due to a decrease in unrecognized tax benefits of $52.4 million (net of interest and penalties of $29.3 million) resulting from expiring statute of limitation periods related to a historical Canadian debt restructuring transaction.

(2)
We issued 6.9 million shares of our common stock in December 2012 upon the closing of a public offering for aggregate net proceeds of $369.3 million.

(3)
For all periods presented, "Adjusted EBITDA" consists of net income (loss) plus accretion of environmental liabilities, depreciation and amortization, goodwill impairment charges, net interest expense, and provision for (benefit from) income taxes. We also exclude loss on early extinguishment of debt, other expense (income), and pre-tax non-cash acquisition accounting inventory adjustments, as these amounts are not considered part of usual business operations. See below for a reconciliation of Adjusted EBITDA to net income for the specified periods. Our management considers Adjusted EBITDA to be a measurement of performance which provides useful information to both management and investors. Adjusted EBITDA should not be considered an alternative to net income or other measurements under generally accepted accounting principles ("GAAP"). Because Adjusted EBITDA is not calculated identically by all companies, our measurements of Adjusted EBITDA may not be comparable to similarly titled measures reported by other companies.

The following is a reconciliation of net income to Adjusted EBITDA for the following periods (in thousands):

 
  Three Months
Ended March 31,
  Year Ended December 31,  
 
  2016   2015   2015   2014   2013   2012   2011  

Net (loss) income

  $ (20,871 ) $ (7,089 ) $ 44,102   $ (28,328 ) $ 95,566   $ 129,674   $ 127,252  

Accretion of environmental liabilities

    2,505     2,619     10,402     10,612     11,541     9,917     9,680  

Depreciation and amortization

    68,902     68,356     274,194     276,083     264,449     161,646     122,663  

Goodwill impairment charge

            31,992     123,414              

Other expense (income)

    350     (409 )   1,380     (4,380 )   (1,705 )   802     (6,402 )

Loss on early extinguishment of debt

                        26,385      

Interest expense, net

    18,980     19,438     76,553     77,668     78,376     47,287     39,389  

Pre-tax, non-cash acquisition accounting inventory adjustments

                    13,559          

(Benefit from) provision for income taxes

    (2,546 )   (4,638 )   65,544     66,850     48,319     (1,944 )   57,426  

Adjusted EBITDA

  $ 67,320   $ 78,277   $ 504,167   $ 521,919   $ 510,105   $ 373,767   $ 350,008  
(4)
Long-term obligations (including current portion) include borrowings under our current and former revolving credit facilities and capital lease obligations, as well as unamortized debt financing costs.

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DESCRIPTION OF OTHER INDEBTEDNESS

Revolving Credit Facility

        We have a revolving credit facility under which Bank of America, N.A. ("BofA") is the administrative and collateral agent (the "Agent") for the lenders and the issuing bank for letters of credit issued under the facility. Under the facility, as amended and restated effective January 17, 2013, Clean Harbors, Inc. (the "Company") has the right to borrow and obtain letters of credit for a combined maximum of up to $300.0 million (with a sub-limit of $250.0 million for letters of credit) and one of the Company's Canadian subsidiaries (the "Canadian Borrower") has the right to obtain up to $100.0 million of revolving loans and letters of credit (with a $75.0 million sub-limit for letters of credit). Availability under the U.S. line is subject to a borrowing base comprised of 85% of the eligible accounts receivable of the Company and its U.S. subsidiaries plus 100% of cash deposited in a controlled account with the Agent, and availability under the Canadian line is subject to a borrowing base comprised of 85% of the eligible accounts receivable of the Canadian Borrower and the Company's other Canadian subsidiaries plus 100% of cash deposited in a controlled account with the Agent's Canadian affiliate. The facility will expire on January 17, 2018.

        Borrowings under the revolving credit facility will bear interest at a rate of, at the Company's option, either (i) LIBOR plus an applicable margin ranging from 1.50% to 2.00% per annum based primarily on the level of the Company's consolidated fixed charge coverage ratio for the most recently completed four fiscal quarter measurement period or (ii) BofA's base rate plus an applicable margin ranging from 0.50% to 1.00% per annum based primarily on such consolidated fixed charge coverage ratio. There is also an unused line fee, calculated on the then unused portion of the lenders' $400.0 million maximum commitments, ranging from 0.250% to 0.375% per annum of the unused commitments. For outstanding letters of credit, the Company pays to the lenders a fee equal to the then applicable LIBOR margin described above, and to the issuing banks a standard fronting fee and customary fees and charges in connection with all amendments, extensions, draws and other actions with respect to letters of credit.

        The Company's obligations under the revolving credit facility (including revolving loans and reimbursement obligations for outstanding letters of credit) are guaranteed by substantially all of the Company's U.S. subsidiaries and secured by a lien on substantially all of the Company's and its U.S. subsidiaries' assets. The Canadian Borrower's obligations under the facility are guaranteed by substantially all of the Company's other Canadian subsidiaries and secured by a lien on the accounts receivable of the Canadian Borrower and the other Canadian subsidiaries. The Company and its U.S. subsidiaries guarantee the obligations of the Canadian Borrower under the facility, but the Canadian Borrower and the other Canadian subsidiaries do not guarantee and are not otherwise responsible for the obligations of the Company and its U.S. subsidiaries.

        Under the revolving credit facility, the Agent would have the right to exercise dominion over the Company's and its subsidiaries' cash (to the extent such cash represents the proceeds of accounts receivable) if the Company's "Liquidity" is less than the greater of (i) $40.0 million and (ii) 10% of the aggregate commitments of the lenders under the facility. Liquidity is defined as the sum of (a) the Company's then U.S. availability under the facility and (b) the lesser of (i) the Canadian Borrower's then availability under the facility and (ii) 60% of the lenders' aggregate commitments to the Canadian Borrower. If Liquidity should be less than the greater of (i) $40.0 million and (ii) 10.0% of the aggregate commitments, the Company would be required to thereafter maintain a consolidated fixed charge coverage ratio of at least 1.00 to 1.00. In addition, the facility contains covenants which will restrict the Company's future ability to make certain types of acquisitions, debt prepayments, investments and distributions if Liquidity (on a pro forma basis after giving effect to such events) is less than between 35% and 15% (depending upon the type of restricted event) of the lenders' aggregate commitments or, if the Company's consolidated fixed charge coverage ratio for the most recently

29


completed four fiscal quarters is at least 1.00 (or, in certain cases, 1.10) to 1.00, less than 17.5% or 15% (depending upon the type of restricted event) of the aggregate commitments.

        We issued on July 30, 2012 and now have outstanding $800.0 million aggregate principal amount of 5.25% unsecured senior notes due 2020 (the "2020 notes"). The 2020 notes mature on August 1, 2020 and bear interest at a rate of 5.25% per annum, computed on the basis of a 360-day year composed of twelve 30-day months and payable semi-annually on August 1 and February 1 of each year. We may redeem some or all of the 2020 notes at any time on or after August 1, 2016, upon not less than 30 nor more than 60 days' notice, at the following redemption prices (expressed as percentages of the principal amount) if redeemed during the twelve-month period commencing on August 1 of the year set forth below, plus, in each case, accrued and unpaid interest, if any, to the date of redemption:

Year
  Percentage  

2016

    102.625 %

2017

    101.313 %

2018 and thereafter

    100.000 %

        At any time prior to August 1, 2016, we may also redeem some or all of the 2020 notes at a redemption price of 100% of the principal amount plus a make-whole premium and any accrued and unpaid interest. Holders may require us to repurchase the 2020 notes at a purchase price equal to 101% of the principal amount, plus any accrued and unpaid interest, upon a change of control of our Company. The 2020 notes are guaranteed by substantially all our current and future domestic restricted subsidiaries.

        The 2020 notes and the related indenture contain various customary covenants and are our and the guarantors' senior unsecured obligations ranking equally with our and the guarantors' existing and future senior unsecured obligations including the old notes, the new notes offered hereby, and the $595.0 million aggregate principal amount of initial notes, and senior to any future indebtedness that is expressly subordinated to the 2020 notes and the guarantees. The 2020 notes and the guarantees rank effectively junior in right of payment to our subsidiaries' secured indebtedness (including loans and reimbursement obligations in respect of outstanding letters of credit) under our revolving credit facility and capital lease obligations to the extent of the value of the assets securing such secured indebtedness. The 2020 notes are not guaranteed by our Canadian or other foreign subsidiaries, and the 2020 notes are structurally subordinated to all indebtedness and other liabilities, including trade payables, of our subsidiaries that are not guarantors of the 2020 notes.

30



THE EXCHANGE OFFER

Purpose and Effect of Exchange Offer; Registration Rights

        We sold the $250.0 million aggregate principal amount of old notes on March 17, 2016 in an unregistered private placement to Goldman, Sachs & Co., as the initial purchaser. The initial purchaser then resold the old notes to investors under an offering circular dated March 14, 2016 in reliance on Rule 144A and Regulation S under the Securities Act.

        As part of this private placement, we entered into a registration rights agreement with the initial purchaser on March 17, 2016. Under the registration rights agreement, we agreed to file the registration statement of which this prospectus is a part. We also agreed:

        Under the circumstances described below, we also agreed to use our commercially reasonable efforts to cause the SEC to declare effective a shelf registration statement with respect to the resale of the old notes. We agreed to keep the shelf registration statement effective until the earlier of the date two years after the shelf registration statement is declared effective under the Securities Act or the date on which there are no longer any old notes outstanding. These circumstances include:

        If we fail to comply with specified obligations under the registration rights agreement, we must pay certain additional interest to the holders of the notes until we have cured all of such failures.

        By participating in the exchange offer, holders of the old notes will receive new notes that are freely tradeable and not subject to restrictions on transfer, subject to the exceptions described below under "Resale of New Notes."

Resale of New Notes

        We believe that the new notes issued in exchange for the old notes may be offered for resale, resold and otherwise transferred by any new note holder without compliance with the registration and prospectus delivery provisions of the Securities Act if the conditions set forth below are met. We base

31


this belief solely on interpretations of the federal securities laws by the SEC set forth in several no-action letters issued to third parties unrelated to us. A no-action letter is a letter from the SEC staff responding to a request for its views as to whether a particular matter complies with the federal securities laws or whether the SEC would refer the matter to the SEC's enforcement division for action. The relevant no-action letters include the Exxon Capital Holdings Corporation letter, which was made available by the SEC on May 13, 1988, the Morgan Stanley & Co. Incorporated letter which was made available by the SEC on June 5, 1991, the K-111 Communications Corporation letter, which was made available by the SEC on May 14, 1993, and the Shearman & Sterling letter, which was made available by the SEC on July 2, 1993. We have not obtained, and do not intend to obtain, our own no-action letter from the SEC staff regarding the resale of the new notes. Instead, holders will be relying on the no-action letters that the SEC staff has issued to third parties in circumstances that we believe are similar to ours. Based on these no-action letters, the following conditions must be met:

        Each holder of old notes that wishes to exchange old notes for new notes in the exchange offer must represent to us that it satisfies all of the above listed conditions. Any holder who tenders in the exchange offer who does not satisfy all of the above listed conditions:

        The SEC considers broker-dealers that acquired old notes directly from us, but not as a result of market-making activities or other trading activities, to be making a distribution of the new notes if they participate in the exchange offer. Consequently, any such holders must comply with the registration and prospectus delivery requirements of the Securities Act in connection with a resale of the new notes.

        Each broker-dealer that receives new notes for its own account in exchange for old notes acquired by such broker-dealer as a result of market-making activities or other trading activities must deliver a prospectus in connection with a resale of the new notes and provide us in the letter of transmittal with a signed acknowledgement of this obligation. The letter of transmittal states that by so acknowledging and delivering a prospectus, a broker-dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act. A broker-dealer may use this prospectus, as amended or supplemented from time to time, in connection with resales of new notes received in exchange for old notes where the broker-dealer acquired the old notes as a result of market-making activities or other trading activities. We have agreed that for a period of 180 days after the expiration date of the exchange offer, we will make this prospectus available to broker-dealers for use in connection with any such resale of the new notes. See "Plan of Distribution."

        Except as described in the prior paragraph, holders may not use this prospectus for an offer to resell, resale or other retransfer of new notes. We are not making the exchange offer to, nor will we accept tenders for exchange from, holders of old notes in any jurisdiction in which the exchange offer or the acceptance of it would not be in compliance with the securities or blue sky laws of that jurisdiction.

32


Terms of the Exchange

        Upon the terms and subject to the conditions set forth in this prospectus and the accompanying letter of transmittal, which we refer to together in this prospectus as the "exchange offer," we will accept any and all old notes validly tendered and not withdrawn prior to 5:00 p.m., New York City time, on the expiration date described below under "Expiration Date; Extensions; Amendments." The date of acceptance for exchange of the old notes, and completion of the exchange offer, is the exchange date, which will be the first business day following the expiration date, unless extended as described in this prospectus. We will issue, on or promptly after the exchange date, an aggregate principal amount of up to $250.0 million of new notes for a like principal amount of outstanding old notes tendered and accepted in connection with the exchange offer. The new notes issued in connection with the exchange offer will be delivered promptly following the exchange date. Holders may tender some or all of their old notes in connection with the exchange offer, but only in denominations of $2,000 and integral multiples of $1,000. The exchange offer is not conditioned upon any minimum amount of old notes being tendered for exchange.

        The terms of the new notes are identical in all material respects to the terms of the old notes, except that:

        The new notes will be newly issued securities for which there is currently no market, and we do not intend to list the notes on any securities exchange. Although the initial purchaser of the old notes has informed us that it intends to make a market in the notes, it is not obligated to do so and may discontinue market-making at any time without notice. Accordingly, a liquid market for the notes may not develop or be maintained.

        The new notes will evidence the same debt as the old notes. The new notes will be issued under the same indenture and entitled to the same benefits under that indenture as the old notes being exchanged. As of the date of this prospectus, $250.0 million in aggregate principal amount of the old notes are outstanding. Old notes accepted for exchange will be retired and cancelled and not reissued.

        In connection with the issuance of the old notes, we arranged for the old notes originally purchased by qualified institutional buyers and those sold in reliance on Regulation S under the Securities Act to be issued and transferable in book-entry form through the facilities of The Depository Trust Company, or "DTC," acting as depositary. We will issue the new notes in the form of a global note registered in the name of DTC or its nominee and each beneficial owner's interest in such global note will be transferable in book-entry form through DTC.

        Holders of old notes do not have any appraisal or dissenters' rights in connection with the exchange offer. We intend to conduct the exchange offer in accordance with the applicable requirements of the Exchange Act and the rules and regulations of the SEC.

        We shall be considered to have accepted validly tendered old notes if and when we have given written notice to that effect to the exchange agent. The exchange agent will act as agent for the tendering holders for the purposes of receiving the new notes from us.

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        If we do not accept any tendered old notes for exchange because of an invalid tender, the occurrence of the other events described in this prospectus or otherwise, we will return these old notes, without expense, to the tendering holder promptly after the expiration date of the exchange offer.

        Holders who tender old notes will not be required to pay brokerage commissions or fees or, subject to the instructions in the letter of transmittal, transfer taxes on exchange of old notes in connection with the exchange offer. We will pay all charges and expenses, other than the applicable taxes described in the section "Fees and Expenses" below, in connection with the exchange offer.

        If we successfully complete the exchange offer, any old notes which holders do not tender or which we do not accept in the exchange offer will remain outstanding and continue to accrue interest. The holders of old notes after the exchange offer in general will not have further rights under the registration rights agreement, including registration rights and any rights to additional interest. Holders of the old notes wishing to transfer their old notes would have to rely on exemptions from the registration requirements of the Securities Act.

Expiration Date; Extensions; Amendments

        The expiration date for the exchange offer is 5:00 p.m., New York City time, on June 22, 2016. We may extend this expiration date in our sole discretion, but in no event to a date later than July 6, 2016. If we so extend the expiration date, the term "expiration date" shall mean the latest date and time to which we extend the exchange offer.

        We reserve the right, in our sole discretion:

        We will give oral or written notice of any delay, extension or termination to the exchange agent. In addition, we will promptly give oral or written notice regarding any delay in acceptance, extension or termination of the offer to the registered holders of old notes. If we amend the exchange offer in a manner that we determine to constitute a material change, or if we waive a material condition, we will promptly disclose the amendment or waiver in a manner reasonably calculated to inform the holders of old notes of the amendment, and extend the offer if required by law.

        Without limiting the manner in which we may choose to make public announcements of any delay in acceptance, extension, termination, amendment or waiver regarding the exchange offer, we shall have no obligation to publish, advertise, or otherwise communicate any public announcement, other than by making a release to a financial news service not later than 9:00 a.m., Eastern time on the business day after the previously scheduled expiration date.

Interest on the New Notes

        Interest on the new notes will accrue at the rate of 5.125% per annum on the principal amount, payable semiannually in arrears on June 1 and December 1. In order to avoid duplicative payment of interest, all interest accrued on old notes that are accepted for exchange before December 1, 2016 will

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be superseded by the interest that is deemed to have accrued on the new notes from June 1, 2016 through the date of the exchange.

Conditions to the Exchange Offer

        Despite any other term of the exchange offer, we will not be required to accept for exchange, or exchange new notes for, any old notes and we may terminate the exchange offer as provided in this prospectus before the exchange offer's termination if:

        The conditions listed above are for our sole benefit and we may assert them regardless of the circumstances giving rise to any of these conditions. We may waive these conditions in our sole discretion in whole or in part at any time. A failure on our part to exercise any of the above rights shall not constitute a waiver of that right, and that right shall be considered an ongoing right, which we may assert at any time and from time to time. However, all conditions other than those dependent upon receipt of any required governmental approval must be satisfied or waived prior to the expiration of the exchange offer (as extended, if applicable), in order for us to complete the exchange offer. Furthermore, if we elect to waive any condition, we must announce that decision in a manner reasonably calculated to inform noteholders of the waiver.

        If we determine in our reasonable discretion that any of the events listed above has occurred, we may, subject to applicable law:

        Any determination by us concerning the above events will be final and binding.

        In addition, we reserve the right in our reasonable discretion to:

        The terms of any such purchases or offers may differ from the terms of the exchange offer.

Procedures for Tendering

        Except in limited circumstances, only a DTC participant listed on a DTC securities position listing with respect to the old notes may tender old notes in the exchange offer. To tender old notes in the exchange offer, holders of old notes that are DTC participants may follow the procedures for book-entry transfer as set forth below under "Book-Entry Transfer" and in the letter of transmittal.

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        In addition, you must comply with one of the following:

        The tender by a holder of old notes will constitute an agreement between such holder and us in accordance with the terms and subject to the conditions set forth in this prospectus and in the letter of transmittal. If less than all the old notes held by a holder are tendered, the tendering holder should fill in the amount of old notes being tendered in the specified box on the letter of transmittal. The entire amount of old notes delivered or transferred to the exchange agent will be deemed to have been tendered unless otherwise indicated.

        The method of delivery of old notes, the letter of transmittal and all other required documents or transmission of an agent's message, as described under "Book-Entry Transfer," to the exchange agent is at the election and risk of the holder. Instead of delivery by mail, we recommend that holders use an overnight or hand delivery service. In all cases, sufficient time should be allowed to assure timely delivery to the exchange agent prior to the expiration of the exchange offer. No letter of transmittal or old notes should be sent to us or DTC. Delivery of documents to DTC in accordance with its procedures will not constitute delivery to the exchange agent.

        Any beneficial holder whose old notes are registered in the name of his or its broker, dealer, commercial bank, trust company or other nominee and who wishes to tender should contact such registered holder promptly and instruct such registered holder to tender on its behalf. If such beneficial holder wishes to tender on its own behalf, such beneficial holder must, prior to completing and executing the letter of transmittal and delivering its old notes, either:

        The transfer of record ownership may take considerable time and may not be completed prior to the expiration date.

        Signatures on a letter of transmittal or a notice of withdrawal, as described in "—Withdrawal of Tenders" below, must be guaranteed by a member firm of a registered national securities exchange or of the National Association of Securities Dealers, Inc., a commercial bank or trust company having an office or correspondent in the United States or an "eligible guarantor institution," within the meaning of Rule 17Ad-15 under the Exchange Act, which we refer to in this prospectus as an "eligible institution," unless the old notes are tendered:

        If the letter of transmittal is signed by a person other than the registered holder of any old notes listed therein, the old notes must be endorsed or accompanied by appropriate bond powers which authorize the person to tender the old notes on behalf of the registered holder, in either case signed as the name of the registered holder or holders appears on the old notes. If the letter of transmittal or any old notes or bond powers are signed by trustees, executors, administrators, guardians,

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attorneys-in-fact, officers of corporations or others acting in a fiduciary or representative capacity, such persons should so indicate when signing and, unless waived by us, evidence satisfactory to us of their authority to so act must be submitted with the letter of transmittal.

        We will determine in our sole discretion all questions as to the validity, form, eligibility, including time of receipt, and acceptance and withdrawal of tendered old notes. We reserve the absolute right to reject any and all old notes not properly tendered or any old notes whose acceptance by us would, in the opinion of our counsel, be unlawful. We also reserve the right to waive any defects, irregularities or conditions of tender as to any particular old notes either before or after the expiration date. However, all conditions other than those dependent upon receipt of any required governmental approval, must be satisfied or waived prior to the expiration of the exchange offer (as extended, if applicable) in order for us to complete the exchange offer. Furthermore, if we elect to waive any condition, we must announce that decision in a manner reasonably calculated to inform noteholders of the waiver. Our interpretation of the terms and conditions of the exchange offer, including the instructions in the letter of transmittal, will be final and binding on all parties. Unless waived, holders must cure any defects or irregularities in connection with tenders of old notes within a period we will determine. Although we intend to request the exchange agent to notify holders of defects or irregularities relating to tenders of old notes, neither we, the exchange agent nor any other person will have any duty or incur any liability for failure to give this notification. We will not consider tenders of old notes to have been made until these defects or irregularities have been cured or waived. The exchange agent will return any old notes that are not properly tendered and as to which the defects or irregularities have not been cured or waived to the tendering holders, unless otherwise provided in the letter of transmittal, promptly following the expiration date.

        In addition, we reserve the right, as set forth above under the caption "Conditions to the Exchange Offer," to terminate the exchange offer.

        By tendering, each holder represents to us, among other things, that:

        If the holder is a broker-dealer which will receive new notes for its own account in exchange for old notes acquired by such broker-dealer as a result of market-making activities or other trading activities, such holder must acknowledge that it will deliver a prospectus in connection with any resale of the new notes.

Book-Entry Transfer

        We understand that the exchange agent will make a request promptly after the date of this prospectus to establish an account with respect to the old notes at DTC for the purpose of facilitating the exchange offer. Any financial institution that is a participant in DTC's system, including Euroclear and Clearsteam, may make book-entry delivery of old notes by causing DTC to transfer such old notes into the exchange agent's DTC account in accordance with DTC's Automated Tender Offer Program procedures for such transfer. The exchange of new notes for tendered old notes will only be made after a timely confirmation of a book-entry transfer of the old notes into the exchange agent's account and timely receipt by the exchange agent of an agent's message.

        The term "agent's message" means a message, transmitted by DTC and received by the exchange agent and forming part of the confirmation of a book-entry transfer, which states that DTC has

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received an express acknowledgment from a participant tendering old notes that such participant has received an appropriate letter of transmittal and agrees to be bound by the terms of the letter of transmittal, and that we may enforce such agreement against the participant. Delivery of an agent's message will also constitute an acknowledgment from the tendering DTC participant that the representations contained in the letter of transmittal and described under "Resale of New Notes" above are true and correct.

Guaranteed Delivery Procedures

        The following guaranteed delivery procedures are intended for holders who wish to tender their old notes but:

        The conditions that must be met to tender old notes through the guaranteed delivery procedures are as follows:

        Upon request to the exchange agent, a notice of guaranteed delivery will be sent to holders who wish to tender their old notes according to the guaranteed delivery procedures set forth above.

Withdrawal of Tenders

        Your tender of old notes pursuant to the exchange offer is irrevocable except as otherwise provided in this section. You may withdraw tenders of old notes at any time prior to 5:00 p.m., New York City time, on the expiration date.

        For a withdrawal to be effective:

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        Any notice of withdrawal must:

        If old notes have been tendered pursuant to the procedure for book-entry transfer described above, any notice of withdrawal must specify the name and number of the account at DTC to be credited with the withdrawn old notes and otherwise comply with the procedures of the applicable facility. We will determine in our sole discretion all questions as to the validity, form and eligibility, including time of receipt, for such withdrawal notices, and our determination shall be final and binding on all parties. Any old notes so withdrawn will be deemed not to have been validly tendered for purposes of the exchange offer and no new notes will be issued with respect to them unless the old notes so withdrawn are validly re-tendered. Any old notes which have been tendered but which are not accepted for exchange will be returned to the holder without cost to such holder promptly after withdrawal, rejection of tender or termination of the exchange offer. Properly withdrawn old notes may be re-tendered by following the procedures described above under "Procedures for Tendering" at any time prior to the expiration date.

Exchange Agent

        We have appointed U.S. Bank National Association as exchange agent in connection with the exchange offer. Holders should direct questions, requests for assistance and for additional copies of this prospectus, the letter of transmittal or notices of guaranteed delivery to the exchange agent addressed as follows:

By Hand or Overnight Courier:   By Facsimile Transmission:
U.S. Bank National Association   (651) 495-8158
60 Livingston Avenue, 1st Floor Bond Drop Window   (For Eligible Institutions Only)
St. Paul, Minnesota 55107   U.S. Bank National Association
Attention: Specialized Finance   Attention: Specialized Finance
(800) 934-6802   Confirm by Telephone:
    (800) 934-6802

        Delivery of a letter of transmittal to any address or facsimile number other than the one set forth above will not constitute a valid delivery.

Fees and Expenses

        We will not make any payments to brokers, dealers or other persons soliciting acceptances of the exchange offer. We will, however, pay the exchange agent reasonable and customary fees for its services and will pay the exchange agent for its related reasonable out-of-pocket expenses, including accounting and legal fees. We may also pay brokerage houses and other custodians, nominees and fiduciaries the reasonable out-of-pocket expenses incurred by them in forwarding copies of this prospectus, letters of

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transmittal and related documents to the beneficial owners of the old notes and in handling or forwarding tenders for exchange.

        Holders who tender their old notes for exchange will not be obligated to pay any transfer taxes. If, however:

then the tendering holder must pay the amount of any transfer taxes due, whether imposed on the registered holder or any other persons. If the tendering holder does not submit satisfactory evidence of payment of these taxes or exemption from them with the letter of transmittal, the amount of these transfer taxes will be billed directly to the tendering holder.

Consequences of Failure to Properly Tender Old Notes in the Exchange

        We will issue the new notes in exchange for old notes under the exchange offer only after timely receipt by the exchange agent of the old notes, a properly completed and duly executed letter of transmittal and all other required documents. Therefore, holders of the old notes desiring to tender old notes in exchange for new notes should allow sufficient time to ensure timely delivery. We are under no duty to give notification of defects or irregularities of tenders of old notes for exchange. Old notes that are not tendered or that are tendered but not accepted by us will, following completion of the exchange offer, continue to be subject to the existing restrictions upon transfer under the Securities Act. Upon completion of the exchange offer, specified rights under the exchange and registration rights agreement, including registration rights and any right to additional interest, will be either limited or eliminated.

        Participation in the exchange offer is voluntary. In the event the exchange offer is completed, we will not be required to register the remaining old notes. Remaining old notes will continue to be subject to the following restrictions on transfer:

        We do not currently anticipate that we will register the remaining old notes under the Securities Act. To the extent that old notes are tendered and accepted in connection with the exchange offer, any trading market for remaining old notes could be adversely affected.

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DESCRIPTION OF THE NOTES

        You can find the definitions of certain terms used in this "Description of the Notes" below under the subheading "—Certain Definitions." In this description, the term "Issuer" refers to Clean Harbors, Inc. and not any of its Subsidiaries.

        On December 7, 2012, the Issuer issued $600.0 million aggregate principal amount of its 5.125% Senior Notes due 2021 (the "initial notes") under an indenture dated as of December 7, 2012 (the "indenture") among itself, the Guarantors and U.S. Bank National Association, as trustee, in an unregistered private placement. As a result of a registered exchange offer completed in May 2013, the unregistered initial notes were exchanged for registered notes having the same terms. As used in this prospectus, the term "initial notes" refers to both the unregistered initial notes sold on December 7, 2012 and the registered notes which were issued in exchange therefor in May 2013. On May 24, 2014, we repurchased $5.0 million of initial notes, leaving $595.0 million aggregate principal amount of initial notes outstanding. On March 17, 2016, we issued the $250.0 million of 5.125% Senior Notes due 2021 (the "old notes") in an unregistered private placement. As described in this prospectus, we are offering to issue up to $250.0 million aggregate principal amount of registered 5.125% Senior Notes due 2021 (the "new notes") in exchange for the old notes under the indenture pursuant to this registered exchange offer. The initial notes and old notes constitute, and the new notes will constitute, "Securities" under the indenture. References to "notes" herein shall include the initial notes, the old notes and the new notes, collectively.

        The terms of the new notes are substantially identical to the terms of the old notes for which they may be exchanged pursuant to the exchange offer, except that the new notes are registered under the Securities Act and do not contain provisions requiring the payment of additional interest in connection with the failure to comply with the registration covenants in the registration rights agreement. The new notes will be pari passu with, and vote together with, any old notes which are not exchanged for new notes and with the initial notes on any matter submitted to the holders of notes under the indenture.

        The following description is a summary of the material provisions of the indenture. It does not restate the terms of the indenture in its entirety. We urge that you carefully read the indenture and the Trust Indenture Act of 1939 (the "TIA"), because the indenture and the TIA govern your rights as holders of the notes, not this description. A copy of the indenture may be obtained from us or the initial purchaser. In this description, "we," "us" or "our" refers only to the Issuer and not any of its Subsidiaries.

General

        The notes are:

        As of March 31, 2016, the Issuer and the Guarantors had no loans and $145.2 million of letters of credit outstanding under the Credit Agreement and no capital lease obligations. The notes and the

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guarantees rank effectively junior in right of payment to our secured Indebtedness (including loans and reimbursement obligations in respect of outstanding letters of credit) under the Credit Agreement and any future capital lease obligations to the extent of the value of the collateral securing such secured Indebtedness. Furthermore, the Issuer's non-guarantor Subsidiaries had as of March 31, 2016, approximately $98.0 million of total liabilities (excluding intercompany liabilities and debt). The notes and the guarantees are structurally subordinated in right of payment to those obligations of the Issuer's non-guarantor Subsidiaries.

        The notes are issued in fully registered form only, without coupons, in denominations of $2,000 and integral multiples of $1,000.

        The trustee serves as paying agent and registrar for the notes. You may present your notes for registration of transfer and exchange at the offices of the registrar, which is the trustee's corporate trust office. The Issuer may change any paying agent and registrar without prior notice.

        The Issuer pays principal (and premium, if any) on the notes at the trustee's corporate office in St. Paul, Minnesota. At the Issuer's option, interest may be paid at the trustee's corporate trust office or by check mailed to the registered address of holders.

Principal, Maturity and Interest

        The notes will mature on June 1, 2021. Additional notes ("Additional Notes") may be issued under the indenture from time to time after the Issue Date (and the new notes shall be Additional Notes), subject to the limitations set forth under "—Certain Covenants—Limitation on Incurrence of Additional Indebtedness." The initial notes, the new notes and any Additional Notes subsequently issued will be treated as a single class for all purposes under the indenture.

        Interest on the notes is payable semiannually in cash on each June 1 and December 1. The first interest payment date for the new notes will be June 1, 2016. The Issuer will make each interest payment to the persons who are registered holders at the close of business on the May 15 and November 15 immediately preceding the applicable interest payment date. Interest on the new notes will accrue from and including June 1, 2016 and will be computed on the basis of a 360-day year of twelve 30-day months.

        The notes are not entitled to the benefit of any mandatory redemption or mandatory sinking fund payment.

Optional Redemption

        The Issuer may redeem all or any portion of the notes, on and after December 1, 2016, upon not less than 30 nor more than 60 days' notice, at the following redemption prices (expressed as percentages of the principal amount) if redeemed during the twelve-month period commencing on December 1 of the year set forth below, plus, in each case, accrued and unpaid interest, if any, to the date of redemption:

Year
  Percentage  

2016

    102.563 %

2017

    101.281 %

2018 and thereafter

    100.000 %

        At any time prior to December 1, 2016, the Issuer may, on one or more occasions, redeem all or any portion of the notes, upon not less than 30 nor more than 60 days' notice, at a redemption price equal to 100% of the principal amount of the notes redeemed, plus the Applicable Premium as of the date of redemption, including accrued and unpaid interest to the redemption date.

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Selection and Notice of Redemption

        If less than all of the notes are to be redeemed at any time, the trustee will select those notes for redemption in compliance with the requirements of the principal national securities exchange, if any, on which the notes are listed or, if the notes are not then listed on a national securities exchange, on a pro rata basis, provided that:

        Notice of redemption will be mailed by first-class mail at least 30 but not more than 60 days before the redemption date to each holder of notes to be redeemed at its registered address. If any note is to be redeemed in part only, the notice of redemption that relates to the note will state the portion of the principal amount to be redeemed. A replacement note in a principal amount equal to the unredeemed portion will be issued in the name of the holder upon cancellation of the original note. On and after the redemption date, interest will cease to accrue on those notes called for redemption if the Issuer has deposited with the paying agent the funds needed to pay the applicable redemption price.

Guarantees

        Each Guarantor unconditionally guarantees, on a senior unsecured basis, jointly and severally, to each holder of notes and the trustee, the full and prompt performance of the Issuer's obligations under the indenture and the notes, including the payment of principal of and interest on the notes. Each Guarantee is:

        The obligations of each Guarantor are limited to the maximum amount which, after giving effect to all other contingent and fixed liabilities of such Guarantor and after giving effect to any collections from or payments made by or on behalf of any other Guarantor in respect of the obligations of such other Guarantor under its Guarantee or pursuant to its contribution obligations under the indenture, will result in the obligations of such Guarantor under the Guarantee not constituting a fraudulent conveyance or fraudulent transfer under federal or state law. Each Guarantor that makes a payment or distribution under a Guarantee shall be entitled to a contribution from each other Guarantor in an amount pro rata, based on the net assets of each Guarantor, determined in accordance with GAAP.

        Each Guarantor may consolidate with or merge into or sell its assets to the Issuer or another Guarantor without limitation, or with other Persons upon the terms and conditions set forth in the indenture. See "—Certain Covenants—Merger, Consolidation and Sale of Assets." In the event all of the Capital Stock of a Guarantor is disposed of by the Issuer, whether by merger, consolidation, sale or otherwise, and the disposition is not in violation of the provisions set forth in "—Certain

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Covenants—Limitation on Asset Sales," the Guarantor's Guarantee will be released. In addition, upon the designation of a Restricted Subsidiary that is a Guarantor as an Unrestricted Subsidiary, which designation is in compliance with the indenture, such Guarantor's Guarantee will be released.

Certain Covenants

        Set forth below are summaries of certain covenants that are contained in the indenture.

Change of Control

        The indenture provides that upon the occurrence of a Change of Control, each holder will have the right to require that the Issuer purchase all or a portion of such holder's notes pursuant to the offer described below (the "Change of Control Offer"), at a purchase price equal to 101% of the principal amount plus accrued interest to the date of purchase. Notwithstanding the occurrence of a Change of Control, the Issuer will not be obligated to repurchase the notes under this covenant if the Issuer has exercised its right to redeem all the notes under the terms of the section titled "Optional Redemption."

        Within 30 days following the date upon which the Change of Control occurred, the Issuer will send, by first-class mail, a notice to each holder, with a copy to the trustee, which notice shall govern the terms of the Change of Control Offer. The notice will state, among other things, the purchase date, which must be no earlier than 30 days nor later than 60 days from the date the notice is mailed, other than as may be required by law (the "Change of Control Payment Date"). Holders electing to have a note purchased pursuant to a Change of Control Offer must surrender the note, with the form entitled "Option of Holder to Elect Purchase" on the reverse of the note completed, to the paying agent at the address specified in the notice prior to the close of business on the third business day prior to the Change of Control Payment Date.

        The Issuer will not be required to make a Change of Control Offer upon a Change of Control if a third party makes the Change of Control Offer in the manner, at the times and otherwise in compliance with the requirements set forth in the indenture applicable to a Change of Control Offer made by the Issuer and purchases all notes validly tendered and not withdrawn under such Change of Control Offer.

        If the Issuer makes a Change of Control Offer, there can be no assurance that it will have available funds sufficient to pay the Change of Control purchase price for all the notes that might be delivered by holders seeking to accept the Change of Control Offer. In the event the Issuer is required to purchase outstanding notes pursuant to a Change of Control Offer, the Issuer expects that it would seek third party financing to the extent it lacks available funds to meet its purchase obligations. However, there can be no assurance that the Issuer would be able to obtain such financing.

        The trustee may not waive the covenant relating to a holder's right to have such holder's note purchased upon a Change of Control. However, the covenant and other provisions contained in the indenture relating to the Issuer's obligation to make a Change of Control Offer may be waived or modified with the written consent of the holders of a majority in principal amount of the notes. Restrictions described in the indenture on the ability of the Issuer and its Restricted Subsidiaries to incur additional Indebtedness, to grant Liens on their property, to make Restricted Payments and to make Asset Sales may also make more difficult or discourage a takeover of the Issuer, whether favored or opposed by our management. Consummation of any such transaction may require redemption or repurchase of the notes, and there can be no assurance that the Issuer or the acquiring party will have sufficient financial resources to effect such redemption or repurchase. Such restrictions and the restrictions on transactions with Affiliates may make more difficult or discourage any leveraged buyout of the Issuer or any of its Restricted Subsidiaries by our management. While such restrictions cover a wide variety of arrangements which have traditionally been used to effect highly leveraged transactions,

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the indenture may not afford you protection in all circumstances from the adverse aspects of a highly leveraged transaction, reorganization, restructuring, merger or similar transaction.

        The Issuer will comply with the requirements of Rule 14e-1 under the Exchange Act and any other securities laws and regulations thereunder to the extent such laws and regulations are applicable in connection with the repurchase of notes pursuant to a Change of Control Offer. To the extent that the provisions of any securities laws or regulations conflict with the "Change of Control" provisions of the indenture, the Issuer will comply with the applicable securities laws and regulations and will not be deemed to have breached the Issuer's obligations under the "Change of Control" provisions of the indenture by so doing.

        The definition of "Change of Control" includes, among other transactions, a disposition of "all or substantially all" of the Issuer's property and assets. With respect to the disposition of property or assets, the phrase "all or substantially all" as used in the indenture varies according to the facts and circumstances of the subject transaction, has no clearly established meaning under relevant law and is subject to judicial interpretation. Accordingly, in certain circumstances, there may be a degree of uncertainty in ascertaining whether a particular transaction would involve a disposition of "all or substantially all" of the property or assets of a Person, and therefore it may be unclear whether a Change of Control has occurred and whether the Issuer is required to make a Change of Control Offer.

Suspension of Covenants

        If on any date following the Issue Date, (i) the notes have Investment Grade Ratings from at least two Rating Agencies and (ii) no Default has occurred and is continuing under the indenture, then, beginning on such day and continuing at all times thereafter until the Reversion Date, as defined below (the occurrence of the events described in the foregoing clauses (i) and (ii) being collectively referred to as a "Covenant Suspension Event"), the covenants listed under the following captions in this "Description of the Notes" section of this prospectus will not be applicable to the notes (collectively, the "Suspended Covenants"):

        If and during any period that the Issuer and the Restricted Subsidiaries are not subject to the Suspended Covenants, the notes will have substantially less covenant protection. In the event that the Issuer and the Restricted Subsidiaries are not subject to the Suspended Covenants under the indenture for any period of time as a result of the foregoing, and on any subsequent date (the "Reversion Date") one or both of the Rating Agencies withdraw their Investment Grade Rating or downgrade the rating assigned to the notes below an Investment Grade Rating, then the Issuer and the Restricted Subsidiaries will thereafter again be subject to the Suspended Covenants under the Indenture with respect to future events. The period of time between the Covenant Suspension Event and the Reversion Date is referred to in this description as the "Suspension Period."

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        On each Reversion Date, all Indebtedness incurred during the Suspension Period will be classified as having been incurred pursuant to clause (3) of the definition of Permitted Indebtedness. Calculations made after the Reversion Date of the amount available to be made as Restricted Payments under "—Limitation on Restricted Payments" will be made as though the covenant described under "—Limitation on Restricted Payments" had been in effect since the Issue Date and throughout the Suspension Period. Accordingly, Restricted Payments made during the Suspension Period will reduce the amount available to be made as Restricted Payments under the first paragraph of "—Limitation on Restricted Payments." As described above, however, no Default or Event of Default will be deemed to have occurred on the Reversion Date as a result of any action or inaction taken or not taken by the Issuer or the Restricted Subsidiaries during the Suspension Period, that would have, if the Suspended Covenants were not suspended, resulted in a breach of, or default under, any of the Suspended Covenants.

        For purposes of the "—Asset Sales" covenant, on the Reversion Date, the Net Proceeds Trigger will be reset to zero.

        During a Suspension Period, the Issuer may not designate any of its Subsidiaries as Unrestricted Subsidiaries.

        There can be no assurance that the notes will ever achieve or maintain Investment Grade Ratings.

Limitation on Incurrence of Additional Indebtedness

        (a)   The Issuer will not, and will not permit any of its Restricted Subsidiaries to, directly or indirectly, create, incur, assume, guarantee, acquire, become liable, contingently or otherwise, with respect to, or otherwise become responsible for payment of (collectively, "incur"), any Indebtedness (other than Permitted Indebtedness); provided, however, that if no Default or Event of Default shall have occurred and be continuing at the time of or as a consequence of the incurrence of any such Indebtedness, the Issuer and any of its Restricted Subsidiaries that is, or upon such incurrence becomes, a Guarantor may incur Indebtedness (including, without limitation, Acquired Indebtedness) and any of its Restricted Subsidiaries that is not or will not become, upon such incurrence, a Guarantor may incur Acquired Indebtedness, in each case, if on the date of the incurrence of such Indebtedness, after giving effect to the incurrence thereof, the Issuer's Consolidated Fixed Charge Coverage Ratio is greater than 2.0 to 1.0.

        (b)   The Issuer will not, and will not permit any Guarantor to, directly or indirectly, incur any Indebtedness which by its terms (or by the terms of any agreement governing such Indebtedness) is expressly subordinated in right of payment to any other Indebtedness of the Issuer or such Guarantor, as the case may be, unless such Indebtedness is also by its terms (or by the terms of any agreement governing such Indebtedness) made expressly subordinate to the notes or the applicable Guarantee, as the case may be, to the same extent and in the same manner as such Indebtedness is subordinated to other Indebtedness of the Issuer or such Guarantor, as the case may be. For purposes of the foregoing, no Indebtedness will be deemed to be subordinated in right of payment to any other Indebtedness of the Issuer or any Guarantor solely by virtue of such Indebtedness being unsecured or by virtue of the fact that the holders of such Indebtedness have entered into one or more intercreditor agreements giving one or more of such holders priority over the other holders in the collateral held by them.

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Limitation on Restricted Payments

        The Issuer will not, and will not cause or permit any of its Restricted Subsidiaries to, directly or indirectly,

(each of the actions listed above being referred to as a "Restricted Payment"), if at the time of such Restricted Payment or immediately after giving effect thereto:

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provided, however, that the sum of clauses (I), (II) and (III) above will not exceed the aggregate amount of all such Investments made by the Issuer or any of its Restricted Subsidiaries in the relevant Person or Unrestricted Subsidiary after the Secured Notes Issue Date.

        As of March 31, 2016, the amount of Restricted Payments permitted to be made pursuant to clause (3) of the immediately preceding paragraph was approximately $530 million.

        However, the provisions set forth in the immediately preceding paragraph do not prohibit:

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        In determining the aggregate amount of Restricted Payments made after the Secured Notes Issue Date in accordance with clause (3) of the immediately preceding paragraph (A) for the period from the Secured Notes Issue date to the Existing Notes Issue Date, only amounts expended pursuant to the first paragraph of Section 4.3 of the Secured Notes Indenture and pursuant to clauses (1), (2)(b), (3)(b)(i), (4) and (5) of the second paragraph of Section 4.3 of the Secured Notes Indenture will be included in the calculation, (y) for the period from the Existing Notes Issue Date to the Issue Date, only amounts expended pursuant to the first paragraph of Section 4.3 of the Existing Notes Indenture and pursuant to clauses (1), (2)(b), (3)(b)(i), (4) and (5) of the second paragraph of Section 4.3 of the Existing Notes Indenture will be included in the calculation and (z) on and after the Issue Date, only amounts expended pursuant to the first paragraph of this "—Limitation on Restricted Payments" covenant and pursuant to clauses (1), (2)(b), (3)(b)(i), (4) and (5) of the second paragraph of this "—Limitation on Restricted Payments" covenant will be included in the calculation.

        Not later than the date of making any Restricted Payment, the Issuer will deliver to the trustee an officers' certificate stating that such Restricted Payment complies with the indenture and setting forth in reasonable detail the basis upon which the required calculations were computed, which calculations may be based upon the Issuer's latest available internal quarterly financial statements.

Limitation on Asset Sales

        The Issuer will not, and will not permit any of its Restricted Subsidiaries to, consummate an Asset Sale unless:

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        On the 366th day after such Asset Sale or such earlier date, if any, as the Issuer's Board of Directors or of such Restricted Subsidiary determines not to apply the Net Cash Proceeds relating to such Asset Sale as set forth in clause (3) of the immediately preceding paragraph (each, a "Net Proceeds Offer Trigger Date"), such aggregate amount of Net Cash Proceeds which have not been applied on or before such Net Proceeds Offer Trigger Date (each a "Net Proceeds Offer Amount") shall be applied by the Issuer or such Restricted Subsidiary to make an offer to purchase from the holders of the notes, and, if required by the terms of any Other Pari Passu Obligations, from the holders of such Other Pari Passu Obligations (the "Net Proceeds Offer") on a date (the "Net Proceeds Offer Payment Date") not less than 30 nor more than 60 days following the applicable Net Proceeds Offer Trigger Date, on a pro rata basis, an amount of notes and Other Pari Passu Obligations equal to the Net Proceeds Offer Amount at a price equal to 100% of the principal amount of the notes and Other Pari Passu Obligations to be purchased, plus accrued and unpaid interest thereon, if any, to the date of purchase.

        If at any time any non-cash consideration received by the Issuer or any Restricted Subsidiary of the Issuer, as the case may be, in connection with such Asset Sale is converted into or sold or otherwise disposed of for cash (other than interest received with respect to any such non-cash consideration), then such conversion or disposition shall be deemed to constitute an Asset Sale hereunder as of the date of such conversion or disposition and the Net Cash Proceeds thereof will be applied in accordance with this covenant.

        The Issuer may defer the Net Proceeds Offer until there is an aggregate unutilized Net Proceeds Offer Amount equal to or in excess of $25.0 million (the "Net Proceeds Trigger") resulting from one or more Asset Sales (at which time, the entire unutilized Net Proceeds Offer Amount, and not just the amount in excess of $25.0 million, shall be applied as required pursuant to the second preceding paragraph).

        Notice of each Net Proceeds Offer pursuant to paragraph (a) will be mailed to the record holders as shown on the register of holders within 25 days following the Net Proceeds Offer Trigger Date, with a copy to the trustee, and will comply with the procedures set forth in the indenture. Upon receiving notice of the Net Proceeds Offer, holders may elect to tender their notes or Other Pari Passu Obligations in whole or in part in denominations of $2,000 or integral multiples of $1,000 in excess thereof in exchange for cash. To the extent holders properly tender notes and Other Pari Passu Obligations in an amount exceeding the Net Proceeds Offer Amount, notes and Other Pari Passu Obligations of tendering holders will be purchased on a pro rata basis (based on amounts tendered). To the extent that the aggregate amount of the notes and Other Pari Passu Obligations tendered pursuant to a Net Proceeds Offer is less than the Net Proceeds Offer Amount, the Issuer may use such excess Net Proceeds Offer Amount for general corporate purposes or for any other purposes not prohibited by the indenture. Upon completion of any such Net Proceeds Offer, the Net Proceeds Offer Amount shall be reset at zero. A Net Proceeds Offer shall remain open for a period of 20 business days or such longer period as may be required by law.

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        The Issuer will comply with the requirements of Rule 14e-1 under the Exchange Act and any other securities laws and regulations thereunder to the extent such laws and regulations are applicable in connection with the repurchase of notes pursuant to a Net Proceeds Offer. To the extent that the provisions of any securities laws or regulations conflict with the "Asset Sale" provisions of the indenture, the Issuer shall comply with the applicable securities laws and regulations and shall not be deemed to have breached their obligations under the "Asset Sale" provisions of the indenture by virtue thereof. The covenant and other provisions contained in the indenture relating to the Issuer's obligation to make a Net Proceeds Offer may be waived or modified with the written consent of the holders of a majority in principal amount of the notes.

Limitations on Dividend and Other Payment Restrictions Affecting Subsidiaries

        The Issuer will not, and will not cause or permit any of its Restricted Subsidiaries (other than a Restricted Subsidiary that has executed a Guarantee) to, directly or indirectly, create or otherwise cause or permit to exist or become effective any encumbrance or restriction on the ability of any Restricted Subsidiary of the Issuer to:

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Limitation on the Issuance and Sale of Capital Stock of Restricted Subsidiaries

        The Issuer will not sell, and will not permit any of its Restricted Subsidiaries, directly or indirectly, to issue or sell, any shares of Capital Stock of a Restricted Subsidiary (including options, warrants or other rights to purchase shares of such Capital Stock) except:

Limitation on Issuances of Guarantees by Restricted Subsidiaries

        The Issuer will not permit any of its Restricted Subsidiaries, directly or indirectly, to guarantee any of the Issuer's Indebtedness or any Indebtedness of the Issuer's Domestic Restricted Subsidiaries, unless (1) such Restricted Subsidiary simultaneously executes and delivers a supplemental indenture to the indenture providing for a senior unsecured Guarantee of payment of the notes by such Restricted Subsidiary, and (2) such Restricted Subsidiary waives and will not in any manner whatsoever claim or take the benefit or advantage of any rights of reimbursement, indemnity or subrogation or any other rights against the Issuer or any other Restricted Subsidiary as a result of any payment by such Restricted Subsidiary under its Guarantee so long as any notes remain outstanding.

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        Notwithstanding the foregoing or the covenant set forth below under "Future Guarantors," any Guarantee by a Restricted Subsidiary may provide by its terms that it shall be automatically and unconditionally released and discharged upon

Future Guarantors

        If the Issuer organizes or acquires any Domestic Restricted Subsidiary having total assets with a book value in excess of $1.0 million (each, a "New Domestic Restricted Subsidiary"), the Issuer will cause such New Domestic Restricted Subsidiary to promptly execute and deliver to the trustee a Guarantee or a joinder thereto.

        Thereafter, such New Domestic Restricted Subsidiary shall be a Guarantor for all purposes of the indenture. Furthermore, the Issuer shall have delivered to the trustee an officers' certificate and an opinion of counsel, each stating that such supplemental indenture complies with the applicable provisions of the indenture, that all conditions precedent in the indenture relating to such transaction have been satisfied and that such supplemental indenture is enforceable, subject to customary qualifications.

Limitation on Liens

        The Issuer will not, and will not cause or permit any of its Restricted Subsidiaries to, directly or indirectly, create, incur, assume or permit or suffer to exist any Lien of any kind against or upon any property or assets of the Issuer or any of its Restricted Subsidiaries whether owned on the Issue Date or acquired after the Issue Date, or any proceeds therefrom, or assign or otherwise convey any right to receive income or profits therefrom unless the notes are equally and ratably secured (or secured on a senior basis to such Lien, if such Lien secures any subordinated Indebtedness), except for the following Liens which are expressly permitted:

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Merger, Consolidation and Sale of Assets

        The Issuer will not, in a single transaction or series of related transactions, consolidate or merge with or into any Person, or sell, assign, transfer, lease, convey or otherwise dispose of all or substantially all of its assets (determined on a consolidated basis for the Issuer and its Restricted Subsidiaries) whether as an entirety or substantially as an entirety to any Person unless:

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        Notwithstanding the foregoing, (a) the merger of the Issuer with an Affiliate incorporated solely for the purpose of reincorporating the Issuer in another jurisdiction shall be permitted and (b) the merger of any Restricted Subsidiary of the Issuer into the Issuer or the transfer, lease, conveyance or other disposition of all or substantially all of the assets of a Restricted Subsidiary of the Issuer to the Issuer shall be permitted so long as the Issuer delivers to the trustee an officers' certificate stating that the purpose of such merger, transfer, lease, conveyance or other disposition is not to consummate a transaction that would otherwise be prohibited by clause (3) of this covenant.

        For purposes of the foregoing, the transfer (by lease, assignment, sale or otherwise, in a single transaction or series of transactions) of all or substantially all of the properties or assets of one or more Restricted Subsidiaries of the Issuer the Capital Stock of which constitutes all or substantially all of the properties and assets of the Issuer shall be deemed to be the transfer of all or substantially all of the properties and assets of the Issuer.

        The indenture provides that upon any consolidation, combination or merger or any transfer of all or substantially all of the assets of the Issuer in accordance with the foregoing in which the Issuer is not the continuing corporation, the successor Person formed by such consolidation or into which the Issuer is merged or to which such conveyance, lease or transfer is made shall succeed to, and be substituted for, and may exercise every right and power of, the Issuer under the indenture and the notes with the same effect as if such Surviving Entity had been named as such.

        Furthermore, the Issuer shall have delivered to the trustee an officers' certificate and an opinion of counsel, each stating that such transaction and, if a supplemental indenture is required in connection with such transaction, such supplemental indenture complies with the applicable provisions of the indenture, that all conditions precedent in the indenture relating to such transaction have been satisfied and that such supplemental indenture is enforceable, subject to customary qualifications.

        Each Guarantor (other than any Guarantor whose Guarantee is to be released in accordance with the terms of such Guarantee and the indenture in connection with any transaction complying with the provisions of "—Limitation on Asset Sales") will not, and the Issuer will not cause or permit any Guarantor to, consolidate with or merge with or into any Person other than the Issuer or any other Guarantor unless:

        Any merger or consolidation of a Guarantor with and into the Issuer (with the Issuer being the surviving entity) or another Guarantor that is a Wholly Owned Restricted Subsidiary of the Issuer need only comply with clause (4) of the first paragraph of this covenant.

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Limitations on Transactions with Affiliates

        (1)   The Issuer will not, and will not permit any of its Restricted Subsidiaries to, directly or indirectly, enter into or permit to exist any transaction or series of related transactions (including, without limitation, the purchase, sale, lease or exchange of any property or the rendering of any service) with, or for the benefit of, any of its Affiliates (each an "Affiliate Transaction"), other than

        (2)   The restrictions set forth in clause (1) shall not apply to:

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Reports to Holders

        The indenture provides that, whether or not required by the rules and regulations of the Commission, so long as any notes are outstanding, the Issuer will file a copy of the following information and reports with the Commission for public availability (unless the Commission will not accept such a filing) and will furnish to the holders of notes and to securities analysts and prospective investors, upon their written request:

        In addition, whether or not required by the rules and regulations of the Commission, the Issuer will file a copy of all such information and reports with the Commission for public availability within the time periods specified in the Commission's rules and regulations (unless the Commission will not accept such a filing) and make such information available to securities analysts and prospective investors upon written request to the Issuer.

        In addition, for so long as any notes remain outstanding, the Issuer shall furnish to the holders and to securities analysts and prospective investors, upon their request, the information required to be delivered pursuant to Rule 144A(d)(4) under the Securities Act.

Events of Default

        The following events are defined in the indenture as "Events of Default":

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        If an Event of Default (other than an Event of Default specified in clause (6) above with respect to the Issuer) shall occur and be continuing, the trustee or the holders of at least 25% in principal amount of outstanding notes may declare the principal of and accrued interest on all the notes to be due and payable by notice in writing to the Issuer and the trustee specifying the respective Event of Default and that it is a "notice of acceleration" (the "Acceleration Notice"), and the same shall become immediately due and payable.

        If an Event of Default specified in clause (6) above with respect to the Issuer occurs and is continuing, then all unpaid principal of and premium, if any, and accrued and unpaid interest on all of the outstanding notes shall automatically become and be immediately due and payable without any declaration or other act on the part of the trustee or any holder.

        The indenture provides that, at any time after a declaration of acceleration with respect to the notes as described in the preceding paragraph, the holders of a majority in principal amount of the notes may rescind and cancel such declaration and its consequences:

        No such rescission will affect any subsequent Default or Event of Default or impair any right consequent thereto.

        The holders of a majority in principal amount of the notes may waive any existing Default or Event of Default under the indenture, and its consequences, except a Default in the payment of the principal of or interest on any notes.

        Holders of the notes may not enforce the indenture or the notes except as provided in the indenture and under the TIA. Subject to the provisions of the indenture relating to the duties of the trustee, the trustee is under no obligation to exercise any of its rights or powers under the indenture at the request, order or direction of any of the holders, unless such holders have offered to the trustee reasonable indemnity. Subject to all provisions of the indenture and applicable law, the holders of a majority in aggregate principal amount of the then outstanding notes have the right to direct the time,

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method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee.

        Under the indenture, the Issuer is required to provide an officers' certificate to the trustee:

No Personal Liability of Directors, Officers, Employees, Members and Stockholders

        No Affiliate, director, officer, employee, limited liability company member or stockholder of the Issuer or any Subsidiary, as such, shall have any liability for any obligations of the Issuer or any Guarantor under the notes or the indenture or any Guarantee or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each holder of notes by accepting a note waives and releases all such liability. The waiver and release were part of the consideration for issuance of the notes.

Legal Defeasance and Covenant Defeasance

        The Issuer may at any time elect to have its obligations and the obligations of any Guarantor discharged with respect to the outstanding notes ("Legal Defeasance"). Such Legal Defeasance means that the Issuer will be deemed to have paid and discharged the entire Indebtedness represented by the outstanding notes, except for:

        In addition, the Issuer may at any time elect to have its obligations released with respect to certain covenants that are described in the indenture ("Covenant Defeasance"). Any omission to comply with such obligations would then not constitute a Default or Event of Default with respect to the notes. If Covenant Defeasance occurs, the Issuer's failure to perform these covenants will no longer constitute an Event of Default with respect to the notes.

        In order to exercise either Legal Defeasance or Covenant Defeasance:

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        However, the opinion of counsel required by clause (2) above is not required if all notes not theretofore delivered to the trustee for cancellation have become due and payable, will become due and payable on the maturity date within one year or are to be called for redemption within one year under arrangements reasonably satisfactory to the trustee for the giving of notice of redemption by the trustee in the Issuer's name, and at the Issuer's expense.

Satisfaction and Discharge

        The indenture will be discharged when:

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        When the indenture is discharged, it ceases to be of further effect except for surviving rights of registration or transfer or exchange of the notes.

Modification of the Indenture

        From time to time, the Issuer, the Guarantors or the trustee, without the consent of the holders, may amend the indenture to cure ambiguities, defects or inconsistencies and to add Guarantees, so long as such change does not, in the good faith determination of the Issuer's Board of Directors, adversely affect the rights of any of the holders of the notes in any material respect. In making its determination, the Issuer's Board of Directors may rely on such evidence as it deems appropriate. Other modifications and amendments of the indenture may be made with the consent of the holders of a majority in principal amount of the then outstanding notes issued under the indenture, except that the consent of each holder affected thereby is required to:

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Governing Law

        The indenture, the notes and any Guarantee are governed by, and construed in accordance with, the laws of the State of New York but without giving effect to applicable principles of conflicts of law to the extent that the application of the law of another jurisdiction would be required thereby.

The Trustee

        U.S. Bank National Association is the trustee under the indenture and has been appointed to act as registrar and paying agent with respect to the notes. The indenture provides that, except during the continuance of an Event of Default, the trustee will perform only such duties as are specifically set forth in the indenture. During the existence of an Event of Default known to the trustee, the trustee will exercise such rights and powers vested in it by the indenture and use the same degree of care and skill in its exercise as a prudent man would exercise or use under the circumstances in the conduct of his own affairs. The trustee is under no obligation to exercise any of its rights or powers under the indenture at the request of any holder of the notes unless such holder shall have offered the trustee security and indemnity satisfactory to it against any loss, liability or expense which might be incurred by it as a result of complying with such request.

        If the trustee becomes a creditor of ours, the indenture and the provisions of the TIA limit the rights of the trustee to obtain payments of its claims or to realize on certain property received in respect of its claims. Subject to the TIA, the trustee is permitted to engage in other transactions; however, if the trustee acquires any conflicting interest as described in the TIA, it must eliminate such conflict or resign.

Certain Definitions

        Set forth below is a summary of certain of the defined terms used in the indenture. You should read the indenture for the full definition of all such terms and any other terms used herein for which no definition is provided.

        "Acquired Indebtedness" means Indebtedness of a Person or any of its Subsidiaries

in each case, not incurred by such Person in connection with, or in contemplation of, such Person becoming a Restricted Subsidiary of the Issuer or such acquisition, merger or consolidation.

        "Affiliate" of any specified Person means any other Person who directly or indirectly through one or more intermediaries controls, or is controlled by, or is under common control with, such specified Person. The term "control" means the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise. "Controlling" and "controlled" shall have correlative meanings.

        "Applicable Premium" means, with respect to any note on any redemption date, the greater of:

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        "Asset Acquisition" means:

        "Asset Sale" means any direct or indirect sale, issuance, conveyance, transfer, lease (other than operating leases entered into in the ordinary course of business), assignment or other transfer for value by the Issuer or any of the Issuer's Restricted Subsidiaries, including any Sale and Leaseback Transaction, to any Person other than the Issuer or a Wholly Owned Restricted Subsidiary of the Issuer of:

        Notwithstanding the preceding, the following items shall not be deemed Asset Sales:

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        "Bankruptcy Law" means Title 11, U.S. Code, or any similar federal, state or foreign law for the relief of debtors.

        "Beneficial Owner" has the meaning assigned to such term in Rule 13d-3 and Rule 13d-5 under the Exchange Act, except that in calculating the beneficial ownership of any particular "person" (as such term is used in Section 13(d)(3) of the Exchange Act), such "person" will be deemed to have beneficial ownership of all securities that such "person" has the right to acquire, whether such right is currently exercisable or is exercisable only upon the occurrence of a subsequent condition, regardless of when such right may be exercised.

        "Board of Directors" of any Person means the board of directors or equivalent governing board of such Person or any duly authorized committee thereof.

        "Board Resolution" means a copy of a resolution certified by the Secretary or an Assistant Secretary of any Person to have been duly adopted by the Board of Directors of such Person and to be in full force and effect on the date of such certification, and delivered to the trustee.

        "Capitalized Lease Obligation" means, at the time any determination thereof is to be made, the amount of the liability of a Person under a capital lease that would at that time be required to be capitalized on a balance sheet in accordance with GAAP, with the stated maturity being the date of the last payment of rent or any other amount due under such lease prior to the first date upon which such lease may be prepaid by the lessee without payment of a penalty.

        "Capital Stock" means:

        "Cash Management Agreement" means any agreement to provide cash management services to the Issuer or any Restricted Subsidiary, including treasury, depository, overdraft, credit or debit card, electronic funds transfer and other cash management arrangements.

        "Cash Equivalents" means:

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        "Change of Control" means the occurrence of one or more of the following:

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        A recent Delaware court case has implied that the provisions in clause (4) above may be unenforceable on public policy grounds. No assurances can be given that a court would enforce clause (4) as written for the benefit of holders of the notes.

        "Commission" means the United States Securities and Exchange Commission.

        "Commodity Agreement" means any commodity futures contract, commodity option or other similar agreement or arrangement entered into by the Issuer or any of its Restricted Subsidiaries designed to protect the Issuer or any of its Restricted Subsidiaries against fluctuations in the price of the commodities at the time used in the ordinary course of the Issuer's business or the business of any of the Issuer's Restricted Subsidiaries.

        "Common Stock" means any and all shares, interests or other participations in, and other equivalents (however designated and whether voting or nonvoting) of, such Person's common stock, whether outstanding on the Issue Date or issued after the Issue Date, including all series and classes of such common stock.

        "Consolidated EBITDA" means, with respect to any Person, for any period, the sum (without duplication) of:

all as determined on a consolidated basis for such Person and its Restricted Subsidiaries in accordance with GAAP as applicable.

        "Consolidated Fixed Charge Coverage Ratio" means, with respect to any Person, the ratio of Consolidated EBITDA of such Person during the four full fiscal quarters for which financial statements are available (the "Four Quarter Period") ending on or prior to the date of the transaction giving rise to the need to calculate the Consolidated Fixed Charge Coverage Ratio (the "Transaction Date") to Consolidated Fixed Charges of such Person for the Four Quarter Period. In addition to and without limitation of the foregoing, for purposes of this definition, "Consolidated EBITDA" and "Consolidated Fixed Charges" shall be calculated after giving effect on a pro forma basis (consistent with the provisions below) for the period of such calculation to:

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        Furthermore, in calculating "Consolidated Fixed Charges" for purposes of determining the denominator (but not the numerator) of this "Consolidated Fixed Charge Coverage Ratio,"

        "Consolidated Fixed Charges" means, with respect to any Person for any period, the sum, without duplication, of:

        "Consolidated Indebtedness" means, as of any date of determination, the sum, without duplication, of (1) the total amount of Indebtedness of the Issuer and its Restricted Subsidiaries, plus (2) the greater of the aggregate liquidation value and maximum fixed repurchase price without regard to any change of control or redemption premiums of all Disqualified Capital Stock of the Issuer and its Restricted Subsidiaries and all Preferred Stock of its Restricted Subsidiaries that are not Guarantors, in each case determined on a consolidated basis in accordance with GAAP.

        "Consolidated Interest Expense" means, with respect to any Person for any period, the sum of, without duplication:

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        "Consolidated Net Income" means, with respect to any Person for any period, the aggregate net income (or loss) of such Person and its Restricted Subsidiaries for such period on a consolidated basis, determined in accordance with GAAP; provided that the following shall be excluded:

        "Consolidated Non-cash Charges" means, with respect to any Person for any period, the aggregate depreciation, amortization, accretion and other non-cash expenses of such Person and its Restricted Subsidiaries reducing Consolidated Net Income of such Person and its Restricted Subsidiaries for such period, determined on a consolidated basis in accordance with GAAP (excluding any such charges constituting an extraordinary item or loss or any such charge (other than non-cash accretion of environmental liabilities required by GAAP) which requires an accrual of or a reserve for cash charges for any future period).

        "Consolidated Secured Leverage Ratio" means, as of any date of determination, the ratio of (a) the Consolidated Indebtedness on such date that is secured by a Lien on any asset of the Issuer or any

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Restricted Subsidiary to (b) Consolidated EBITDA of the Issuer and its Restricted Subsidiaries during the four full fiscal quarters for which financial statements are available ending on or prior to the date of the transaction giving rise to the need to calculate the Consolidated Secured Leverage Ratio, in each case with such pro forma adjustments as are appropriate and consistent with the pro forma adjustment provisions set forth in the definition of "Consolidated Fixed Charge Coverage Ratio."

        "Consolidated Total Assets" means the total assets of the Issuer and its Restricted Subsidiaries, determined on a consolidated basis in accordance with GAAP, as of the most recent balance sheet of the Issuer.

        "Credit Agreement" means, collectively, (i) one or more credit facilities, including, without limitation, the third amended and restated credit agreement dated as of May 31, 2011, among the Issuer, as the U.S. borrower, Clean Harbors Industrial Services Canada, Inc., as the Canadian borrower, the financial institutions party to such agreement in their capacities as lenders, Bank of America, N.A., as administrative agent, and certain other parties and (ii) the related documents (including, without limitation, any guarantee agreements, promissory notes, fee letters and security documents), in each case as such agreements, other agreements and security documents may be amended (including any amendment and restatement), supplemented or otherwise modified from time to time, including any agreement extending the maturity of, refinancing, replacing or otherwise restructuring (including increasing the amount of available borrowings or availability of letters of credit thereunder or adding Restricted Subsidiaries of the Issuer as additional borrowers or guarantors thereunder) all or any portion of the Indebtedness under such agreements, other agreements or any successor or replacement agreement or agreements and whether by the same or any other agent, lender or group of lenders, or issuers of letters of credit.

        "Currency Agreement" means any foreign exchange contract, currency swap agreement or other similar agreement or arrangement designed to protect the Issuer or any Restricted Subsidiary of the Issuer against fluctuations in currency values.

        "Debtor Relief Laws" means the Bankruptcy Law, and all other liquidation, conservatorship, bankruptcy, assignment for the benefit of creditors, moratorium, rearrangement, receivership, insolvency, reorganization, or similar debtor relief laws or regulations of the United States or other applicable jurisdictions from time to time in effect and affecting the rights of creditors generally.

        "Default" means an event that is, or with the passage of time or the giving of notice or both would be, an Event of Default.

        "Disqualified Capital Stock" means that portion of any Capital Stock which, by its terms (or by the terms of any security into which it is convertible or for which it is exchangeable at the option of the holder thereof), or upon the happening of any event (other than an event which would constitute a Change of Control), matures or is mandatorily redeemable, pursuant to a sinking fund obligation or otherwise, or is redeemable at the sole option of the holder thereof (except, in each case, upon the occurrence of a Change of Control) on or prior to the final maturity date of the notes.

        "Domestic Restricted Subsidiary" means any Restricted Subsidiary of the Issuer incorporated or otherwise organized or existing under the laws of the United States, any State or the District of Columbia, other than any Restricted Subsidiary that is a Subsidiary of a Foreign Restricted Subsidiary.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended, or any successor statutes.

        "Existing Notes" means the Issuer's 5.25% Senior Notes due 2020.

        "Existing Notes Indenture" means the indenture, dated as of July 30, 2012, pursuant to which the Existing Notes were issued.

        "Existing Notes Issue Date" means July 30, 2012.

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        "fair market value" means with respect to any asset or property, the price which could be negotiated in an arm's-length, free market transaction, for cash, between a willing seller and a willing and able buyer, neither of whom is under undue pressure or compulsion to complete the transaction. Fair market value shall be determined conclusively by the Issuer's Board of Directors acting reasonably and in good faith and, to the extent otherwise required by the indenture, shall be evidenced by a Board Resolution of the Issuer's Board of Directors delivered to the trustee.

        "Foreign Restricted Subsidiary" means any of the Issuer's Restricted Subsidiaries incorporated or organized in any jurisdiction outside of the United States.

        "Foreign Subsidiary Total Assets" means the total assets of Foreign Restricted Subsidiaries of the Issuer, determined on a consolidated basis in accordance with GAAP, as of the most recent balance sheet of the Issuer.

        "GAAP" means generally accepted accounting principles set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as may be approved by a significant segment of the accounting profession of the United States, which are in effect as of the Issue Date.

        "guarantee" means any obligation, contingent or otherwise, of any Person directly or indirectly guaranteeing any Indebtedness of any other Person, including any obligation, direct or indirect, contingent or otherwise, of such Person

        Notwithstanding the preceding, "guarantee" does not include endorsements for collection or deposit in the ordinary course of business. The term "guarantee" used as a verb has a corresponding meaning.

        "Guarantee" means the guarantee by each Guarantor of the Issuer's obligations under the indenture.

        "Guarantor" means:

provided that any Person constituting a Guarantor as described above shall cease to constitute a Guarantor when its Guarantee is released in accordance with the terms of the indenture.

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        "Indebtedness" means with respect to any Person any indebtedness of such Person, without duplication, in respect of:

        For purposes of this definition of Indebtedness, the "maximum fixed repurchase price" of any Disqualified Capital Stock which does not have a fixed repurchase price shall be calculated in accordance with the terms of such Disqualified Capital Stock as if such Disqualified Capital Stock were purchased on any date on which Indebtedness shall be required to be determined pursuant to the indenture, and if such price is based upon, or measured by, the fair market value of such Disqualified Capital Stock, such fair market value shall be determined reasonably and in good faith by the Board of Directors of the issuer of such Disqualified Capital Stock. For purposes of the covenant described above under the caption "Limitation on Incurrence of Additional Indebtedness," in determining the principal amount of any Indebtedness to be incurred by the Issuer or any Restricted Subsidiary or which is outstanding at any date, the principal amount of any Indebtedness which provides that an amount less than the principal amount shall be due upon any declaration of acceleration shall be the accreted value of the Indebtedness at the date of determination.

        "Independent Financial Advisor" means a firm:

        "Interest Swap Obligations" means the obligations of any Person pursuant to any arrangement with any other Person, whereby, directly or indirectly, such Person is entitled to receive from time to time periodic payments calculated by applying either a floating or a fixed rate of interest on a stated notional amount in exchange for periodic payments made by such other Person calculated by applying a

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fixed or a floating rate of interest on the same notional amount and shall include, without limitation, interest rate swaps, caps, floors, collars and similar agreements.

        "Investment" means, with respect to any Person, any direct or indirect loan or other extension of credit, including a guarantee, or capital contribution to (by means of any transfer of cash or other property to others or any payment for property or services for the account or use of others), or any purchase or acquisition by such Person of any Capital Stock, bonds, notes, debentures or other securities or evidences of Indebtedness issued by, any Person. "Investment" does not include extensions of trade credit by, prepayment of expenses by, and receivables owing to, the Issuer and its Restricted Subsidiaries on commercially reasonable terms in accordance with the Issuer's normal trade practices or those of such Restricted Subsidiary, as the case may be. For purposes of the "Limitation on Restricted Payments" covenant:

        If the Issuer or any of its Restricted Subsidiaries of the Issuer sells or otherwise disposes of any Common Stock of any direct or indirect Restricted Subsidiary of the Issuer such that, after giving effect to any such sale or disposition, such Person ceases to be a Restricted Subsidiary of the Issuer, the Issuer shall be deemed to have made an Investment on the date of any such sale or disposition equal to the fair market value of the Common Stock of that Restricted Subsidiary not sold or disposed of.

        "Investment Grade Rating" means a rating equal to or higher than Baa3 (or the equivalent) by Moody's and BBB– (or the equivalent) by S&P, or an equivalent rating by any other agency referred to in clause (2) of the definition of Rating Agency.

        "Issue Date" means December 7, 2012.

        "Lien" means any lien, mortgage, deed of trust, pledge, security interest, charge or encumbrance of any kind, including any conditional sale or other title retention agreement, any lease in the nature thereof and any agreement to give any security interest.

        "Net Cash Proceeds" means (a) with respect to any Asset Sale, the proceeds in the form of cash or Cash Equivalents including payments in respect of deferred payment obligations when received in the form of cash or Cash Equivalents (other than the portion of any such deferred payment constituting interest) received by the Issuer or any of its Restricted Subsidiaries from such Asset Sale net of:

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and (b) with respect to any issuance or sale of Capital Stock, the cash proceeds of such issuance or sale, net of attorneys' fees, accountants' fees, underwriters' or placement agents' or initial purchasers' fees, discounts or commissions and brokerage, consultant and other fees and expenses actually incurred in connection with such issuance or sale and net of taxes paid or payable as a result thereof.

        "New Domestic Restricted Subsidiary" has the meaning set forth in the "Future Guarantors" covenant.

        "Obligations" means all obligations for principal, premium, interest, penalties, fees, indemnifications, reimbursements, damages and other liabilities payable under the documentation governing any Indebtedness.

        "Other Pari Passu Obligations" means any Additional Notes and any other Indebtedness that is pari passu in right of payment with the notes.

        "Permitted Business" means the business of the Issuer and the Issuer's Restricted Subsidiaries as existing on the Issue Date and any other businesses that are the same, similar or reasonably related, ancillary or complementary thereto and reasonable extensions thereof.

        "Permitted Holders" means (i) Alan S. McKim; (ii) the spouse and lineal descendants of Alan S. McKim; (iii) any controlled Affiliate of any of the foregoing; (iv) in the event of the incompetence or death of any of the Persons described in clause (i) or (ii), such Person's estate, executor, administrator, committee or other personal representative, in each case who at any particular date will beneficially own or have the right to acquire, directly or indirectly, Capital Stock of the Issuer owned by such Person; or (v) any trusts, general partnerships or limited partnerships created for the benefit of the Persons described in clause (i), (ii), or (iv) or any trust for the benefit of any such trust general partnership or limited partnership.

        "Permitted Indebtedness" means, without duplication, each of the following:

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        For purposes of determining compliance with the "Limitation on Incurrence of Additional Indebtedness" covenant,

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        "Permitted Investments" means:

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        "Permitted Liens" means the following types of Liens:

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        "Person" means an individual, partnership, corporation, limited liability company, unincorporated organization, trust or joint venture, or a governmental agency or political subdivision thereof or any other entity.

        "Preferred Stock" of any Person means any Capital Stock of such Person that has preferential rights to any other Capital Stock of such Person with respect to dividends or redemptions or upon liquidation.

        "Purchase Money Indebtedness" means Indebtedness of the Issuer and its Restricted Subsidiaries incurred in the normal course of business for the purpose of financing all or any part of the purchase price, or the cost of installation, construction or improvement, of property or equipment or other related assets and any Refinancing thereof.

        "Qualified Capital Stock" means any Capital Stock that is not Disqualified Capital Stock.

        "Qualified Receivables Transaction" means any transaction or series of transactions that may be entered into by the Issuer or any of its Restricted Subsidiaries in which the Issuer or any of its Restricted Subsidiaries may sell, convey or otherwise transfer to (1) a Receivables Entity (in the case of a transfer by the issuer or any of its Restricted Subsidiaries) and (2) any other Person (in the case of a transfer by a Receivables Entity), or may grant a security interest in Receivables and Related Assets; provided that such transaction is on market terms at the time the Issuer or such Restricted Subsidiary or the Receivables Entity entered into the transaction.

        "Rating Agency" means (1) each of Moody's and S&P and (2) solely to the extent Moody's or S&P ceases to rate the notes for reasons outside of the Issuer's control, a "nationally recognized statistical rating organization" within the meaning of Rule 15c3-1(c)(2)(vi)(F) under the Exchange Act selected by the Issuer as a replacement agency for Moody's or S&P, as the case may be.

        "Receivables and Related Assets" means any accounts receivable (whether existing on the Issue Date or arising thereafter) of the Issuer or any of its Restricted Subsidiaries, and any assets related thereto, including, without limitation, all collateral securing such accounts receivable, all contracts and contract rights and all guarantees or other obligations in respect of such accounts receivable, proceeds of such accounts receivable and other assets which are customarily transferred or in respect of which security interests are customarily granted in connection with asset securitization transactions involving accounts receivable.

        "Receivables Entity" means a Wholly Owned Restricted Subsidiary of the Issuer (or another Person in which the Issuer or any Subsidiary of the Issuer makes an Investment and to which the Issuer or any Subsidiary of the Issuer transfers Receivables and Related Assets) that engages in no activities other than in connection with the financing of accounts receivable and that is designated by the Board of Directors of the Issuer (as provided below) as a Receivables Entity:

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        Any such designation by the Board of Directors of the Issuer shall be evidenced to the trustee by filing with the trustee a Board Resolution giving effect to such designation and an officers' certificate certifying that such designation complied with the preceding conditions.

        "Refinance" means, in respect of any security or Indebtedness, to refinance, extend, renew, refund, repay, prepay, redeem, defease or retire, or to issue a security or Indebtedness in exchange or replacement for, such security or Indebtedness in whole or in part. "Refinanced" and "Refinancing" shall have correlative meanings.

        "Refinancing Indebtedness" means any Refinancing by the Issuer or any Restricted Subsidiary of the Issuer of (A) for purposes of clause (13) of the definition of "Permitted Indebtedness," Indebtedness incurred or existing in accordance with the "Limitation on Incurrence of Additional Indebtedness" covenant (other than pursuant to clause (2), (4), (5), (6), (7), (8), (9), (10), (11), (12), (14) or (15) of the definition of "Permitted Indebtedness") or (B) for any other purpose, Indebtedness incurred in accordance with the "Limitation on Incurrence of Additional Indebtedness" covenant, in each case that does not:

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provided that

        "Restricted Payment" has the meaning set forth in the "Limitation on Restricted Payments" covenant.

        "Restricted Subsidiary" of any Person means any Subsidiary of such Person which at the time of determination is not an Unrestricted Subsidiary.

        "Sale and Leaseback Transaction" means any direct or indirect arrangement with any Person or to which any such Person is a party, providing for the leasing to the Issuer or a Restricted Subsidiary of the Issuer of any property, whether owned by the Issuer or any Restricted Subsidiary at the Issue Date or later acquired, which has been or is to be sold or transferred by the Issuer or such Restricted Subsidiary to such Person or to any other Person from whom funds have been or are to be advanced by such Person on the security of such property.

        "Secured Notes" means the Issuer's previously outstanding 7.625% Senior Secured Notes due 2016 that were either repurchased pursuant to a tender offer and consent solicitation or redeemed in accordance with the terms of the Secured Notes Indenture.

        "Secured Notes Indenture" means the indenture, dated as of August 14, 2009, pursuant to which the Secured Notes were issued and subsequently repurchased or redeemed.

        "Secured Notes Issue Date" means August 14, 2009.

        "Significant Subsidiary" means (1) any Restricted Subsidiary that would be a "significant subsidiary" as defined in Regulation S-X under the Securities Act as such Regulation is in effect on the Issue Date and (2) any Restricted Subsidiary that, when aggregated with all other Restricted Subsidiaries that are not otherwise Significant Subsidiaries and as to which any event described in clause (6) or (7) under "—Events of Default" has occurred and is continuing, would constitute a Significant Subsidiary under clause (1) of this definition.

        "Subsidiary," with respect to any Person, means:

        "Treasury Rate" means, as of any redemption date, the yield to maturity as of such redemption date of United States Treasury securities with a constant maturity (as compiled and published in the most recent Federal Reserve Statistical Release H.15 (519) that has become publicly available at least two business days prior to the redemption date (or, if such Statistical Release is no longer published, any publicly available source of similar market data)) most nearly equal to the period from the redemption date to December 1, 2016; provided, however, that if the period from the redemption date

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to December 1, 2016 is less than one year, the weekly average yield on actually traded United States Treasury securities adjusted to a constant maturity of one year will be used.

        "Unrestricted Subsidiary" means (1) any Subsidiary of any Person that is designated an Unrestricted Subsidiary by the Board of Directors of such Person in the manner provided below and (2) any Subsidiary of an Unrestricted Subsidiary. The Board of Directors may designate any Subsidiary, including any newly acquired or newly formed Subsidiary, to be an Unrestricted Subsidiary only if:

        The Board of Directors may designate any Unrestricted Subsidiary to be a Restricted Subsidiary only if:

        "Weighted Average Life to Maturity" means, when applied to any Indebtedness at any date, the number of years obtained by dividing

        "Wholly Owned Restricted Subsidiary" of any Person means any Restricted Subsidiary of such Person of which all the outstanding voting securities (other than in the case of a Foreign Restricted Subsidiary, directors' qualifying shares or an immaterial amount of shares required to be owned by other Persons pursuant to applicable law) are owned by such Person or any Wholly Owned Restricted Subsidiary of such Person.

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UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS

        The following is a summary of the material United States federal income tax considerations that may be relevant to the exchange, ownership and disposition of the notes. This summary is based on the Internal Revenue Code of 1986, as amended (the "Code"), the Treasury regulations promulgated thereunder and administrative and judicial interpretations thereof, all as of the date hereof, and all of which are subject to change, possibly on a retroactive basis. We have not and will not seek a ruling from the Internal Revenue Service (the "IRS") regarding the matters discussed below, and we cannot assure you that the IRS will not challenge one or more of the tax considerations described herein.

        Unless otherwise stated, this summary deals only with the new notes offered to be exchanged for old notes purchased for cash on original issue at their issue price (as defined below) and held as capital assets (generally, property held for investment) and does not address tax considerations applicable to investors that may be subject to special tax rules including banks, thrifts, real estate investment trusts, regulated investment companies, tax exempt organizations, insurance companies, dealers in securities or currencies, traders in securities that elect to use the mark-to-market method of accounting for their securities holdings, persons that will hold the notes as part of a hedging transaction, "straddle," "synthetic security" or "conversion transaction" for tax purposes, partnerships or other pass through entities for U.S. federal income tax purposes (or investors in such entities), U.S. expatriates, or U.S. holders (as defined below) that have a "functional currency" other than the U.S. dollar. If an entity treated as a partnership for United States federal income tax purposes holds the notes, the tax treatment of a partner will generally depend on the status of the partner and the activities of the partnership. If you are a partner of a partnership holding the notes, you should consult your own tax advisor. Further, this summary does not discuss alternative minimum tax consequences, if any, or any state, local or foreign tax consequences to holders of the notes.

U.S. Holders of Notes

        For purposes of this summary, a "U.S. holder" means the beneficial owner of a note that is for United States federal income tax purposes:

        Stated Interest.    Payments of stated interest on a note generally will be taxable to a U.S. holder as ordinary interest income at the time such payments are accrued or are received in accordance with the holder's regular method of tax accounting.

        Amortizable Bond Premium.    If a U.S. holder's initial purchase price for a note (excluding any amounts attributable to pre-issuance accrued interest) exceeds the stated principal amount of such note, the U.S. holder will be considered to have amortizable bond premium equal to such excess. Subject to the limitation described below, a U.S. holder generally may elect to amortize any amortizable bond premium over the remaining term of such note on a constant yield method (based on the note's yield to maturity) and use the amortizable bond premium allocable to an accrual period to offset stated interest otherwise required to be included in income with respect to such note in that accrual period.

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However, because the notes may be redeemed by us prior to maturity at a premium, special rules apply that may reduce, eliminate or defer the amount of premium that may be amortized with respect to the notes.

        If a U.S. holder makes the election to amortize bond premium, such holder will be required to reduce its adjusted tax basis in such note by the amount of the premium amortized in any year. An election to amortize bond premium will also apply to all other taxable debt instruments held or subsequently acquired by the U.S. holder on or after the first day of the first taxable year for which the election is made. Such an election may not be revoked without the consent of the IRS. You should consult your own tax advisors about this election.

        Sale, Exchange or Other Disposition of Notes.    Upon a sale, exchange (other than an exchange pursuant to the exchange offer), redemption, retirement or other taxable disposition of a note, a U.S. holder will generally recognize taxable capital gain or loss equal to the difference between (A) the amount of cash and the fair market value of any property received (excluding amounts attributable to accrued but unpaid stated interest (other than pre-issuance accrued interest), which will be taxable as ordinary income to the extent not previously included in income, as discussed above) and (B) the holder's adjusted tax basis in the note. The U.S. holder's adjusted tax basis in a note generally will be such holder's original cost for such note, reduced by any payments of pre-issuance accrued interest previously received and by any bond premium previously amortized. The gain or loss will generally be long-term capital gain or loss provided that the U.S. holder's holding period for the note exceeds one year. Under current U.S. federal income tax law, certain non-corporate U.S. holders, including individuals, are eligible for preferential rates of U.S. federal income taxation in respect of long-term capital gains. The deductibility of capital losses is subject to certain limitations.

        The Exchange Offer.    The exchange of the old notes for new notes pursuant to the exchange offer will not constitute an exchange or other taxable disposition for United States federal income tax purposes. Therefore, a holder will have the same issue price, holding period and adjusted tax basis in the new note as in the note surrendered. In addition, each holder of notes will continue to be required to include interest on the notes in its gross income in accordance with its regular method of accounting for United States federal income tax purposes, and all other United States federal income tax consequences of holding and disposing of new notes will be the same as the United States federal income tax consequences of holding and disposing of old notes.

        Medicare Tax.    Certain U.S. holders that are individuals, estates or trusts will be subject to a 3.8% tax on all or a portion of their "net investment income," which will generally include all or a portion of their interest income and net gains from the disposition of the notes. Each U.S. holder that is an individual, estate or trust is urged to consult its tax advisors regarding the applicability of the Medicare tax to its income and gains in respect of its investment in the notes.

        Information Reporting and Backup Withholding Tax.    In general, information reporting requirements will apply to payments of interest on the notes and the proceeds of a sale or other disposition (including a retirement or redemption) of the notes. A U.S. holder will generally be subject to backup withholding (currently at a rate of 28%) on such payments and proceeds unless the holder provides to the applicable paying agent a correct taxpayer identification number and certain other information, or the holder otherwise establishes an exemption.

        Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a U.S. holder will be allowed as a credit against the holder's United States federal income tax and may entitle the holder to a refund, provided that the required information is timely furnished to the IRS.

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Non-U.S. Holders of Notes

        Except as modified for estate tax purposes, for purposes of this summary, a "non-U.S. holder" means a beneficial owner of a note that is an individual, corporation, estate or trust and is not a U.S. holder (as defined above).

        Interest Income.    Generally, interest income of a non-U.S. holder will qualify for the "portfolio interest" exemption and therefore will not be subject to United States federal income tax or withholding tax, provided that:

        If a non-U.S. holder cannot satisfy the requirements described above, payments of interest made to such holder generally will be subject to U.S. federal withholding tax at the rate of 30%, unless the holder provides to us or our paying agent a properly executed IRS Form W-8BEN or W-8BEN-E (or suitable substitute form) establishing an exemption from or a reduction in the withholding tax under the benefit of an applicable tax treaty.

        If any interest on the notes is effectively connected with a U.S. trade or business conducted by a non-U.S. holder, such non-U.S. holder will be subject to United States federal income tax generally in the same manner as a U.S. holder (unless an applicable income tax treaty provides otherwise). If a non-U.S. holder is eligible for the benefits of an income tax treaty between the United States and its country of residence, any "effectively connected" income will generally be subject to United States federal income tax only if it is also attributable to a permanent establishment maintained by such non-U.S. holder in the United States. If a non-U.S. holder is a corporation, that portion of its earnings and profits that is effectively connected with its U.S. trade or business also may be subject to a "branch profits tax" at a 30% rate, although an applicable income tax treaty may provide for a lower rate.

        If interest received with respect to the notes is effectively connected income (whether or not a treaty applies), the 30% withholding tax described above will not apply (assuming an appropriate certification is provided).

        Sale, Exchange or Disposition of Notes.    Subject to the discussion of backup withholding below, a non-U.S. holder generally will not be subject to United States federal income tax or withholding tax on any gain realized on the sale, exchange, redemption, retirement, or other taxable disposition of the notes unless:

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        The Exchange Offer.    As described above under "—U.S. Holders of Notes—The Exchange Offer," the exchange of a note pursuant to the exchange offer will be a nontaxable event to a non-U.S. holder.

        Information Reporting and Backup Withholding.    Payments to a non-U.S. holder of interest on a note, and amounts withheld from such payments, if any, generally will be required to be reported to the IRS and to the non-U.S. holder. Copies of the information returns reporting such interest payments and any withholding may also be made available to the tax authorities in the country in which the non-U.S. holder resides under the provisions of an applicable income tax treaty.

        Backup withholding at a rate of 28% generally will not apply to interest payments on the notes to a non-U.S. holder if such holder has complied with the applicable certification requirements described in subparagraph (5) in the "Interest Income" section above or otherwise establishes an exemption under the applicable Treasury regulations.

        Payment of the proceeds of a sale or other disposition (including a retirement or redemption) of a note effected by the United States office of a United States or foreign broker will be subject to information reporting requirements and backup withholding unless the non-U.S. holder properly certifies under penalties of perjury as to its foreign status or the non-U.S. holder otherwise establishes an exemption. Information reporting requirements and backup withholding generally will not apply to any payment of the proceeds of a sale or other disposition of a note effected outside the United States by a foreign office of a broker. However, unless such a broker has documentary evidence in its records that the beneficial owner is a non-U.S. holder and certain other conditions are met, or a non-U.S. holder otherwise establishes an exemption, information reporting will apply to a payment of the proceeds of a sale or other disposition of a note effected outside the United States by such a broker if the broker:

        Backup withholding is not an additional tax. Any amount withheld under the backup withholding rules may be credited against the holder's United States federal income tax liability and any excess may be refundable if the proper information is timely provided to the IRS.

        The United States federal income tax discussion set forth above is included for general information only. Holders should consult their own tax advisors with respect to the tax consequences to them of the exchange, ownership and disposition of the notes, including the tax consequences under state, local, foreign and other tax laws and any proposed change in applicable laws.

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PLAN OF DISTRIBUTION

        Each broker-dealer that receives new notes for its own account in connection with the exchange offer must acknowledge that it will deliver a prospectus in connection with any resale of those new notes. A broker-dealer may use this prospectus, as amended or supplemented from time to time, in connection with resales of new notes received in exchange for old notes where such broker-dealer acquired old notes as a result of market-making activities or other trading activities. We have agreed that for a period of 180 days after the expiration date of the exchange offer, we will make available a prospectus, as amended or supplemented, meeting the requirements of the Securities Act to any broker-dealer for use in connection with those resales.

        We will not receive any proceeds from any sale of new notes by broker-dealers. Broker-dealers may sell new notes received by them for their own account pursuant to the exchange offer from time to time in one or more transactions in the over-the-counter market, in negotiated transactions, through the writing of options on the new notes or a combination of those methods of resale, at market prices prevailing at the time of resale, at prices related to such prevailing market prices or negotiated prices. Any such resale may be made directly to purchasers or to or through brokers or dealers who may receive compensation in the form of commissions or concessions from any broker-dealer or the purchasers of any new notes. Any broker-dealer that resells new notes that were received by it for its own account pursuant to the exchange offer and any broker or dealer that participates in a distribution of such new notes may be deemed to be an "underwriter" within the meaning of the Securities Act. A profit on any such resale of new notes and any commissions or concessions received by any such persons may be deemed to be underwriting compensation under the Securities Act. The letter of transmittal states that, by acknowledging that it will deliver and by delivering a prospectus, a broker-dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act.

        For a period of 180 days after the expiration date of the exchange offer, we will promptly send additional copies of this prospectus and any amendment or supplement to this prospectus to any broker-dealer that requests these documents in the letter of transmittal. We will indemnify the holders of the old notes, including any broker-dealers, against specified liabilities, including liabilities under the Securities Act.


LEGAL MATTERS

        Davis, Malm & D'Agostine, P.C., Boston, Massachusetts, has passed upon the validity and enforceability of the new notes and the guarantees for Clean Harbors and the Guarantors. As of May 1, 2016, shareholders in Davis, Malm & D'Agostine, P.C., beneficially owned an aggregate of 10,500 shares of our common stock (including 3,000 shares owned by, or for the benefit of, members of their immediate families).


EXPERTS

        The consolidated financial statements and the related financial statement schedule as of December 31, 2015 and 2014, and for each of the three years in the period ended December 31, 2015, incorporated by reference in this prospectus, and the effectiveness of Clean Harbors, Inc. and subsidiaries' internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports, which are incorporated herein by reference. Such consolidated financial statements and financial statement schedule have been so incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

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TABLE OF CONTENTS
WHERE YOU CAN FIND ADDITIONAL INFORMATION
DOCUMENTS INCORPORATED BY REFERENCE
Market and Related Information
Forward-Looking Statements
SUMMARY
Our Company
Our Services
The Environmental Services Industry
Corporate Information
The Exchange Offer
Summary Description of the New Notes
RISK FACTORS
USE OF PROCEEDS
RATIO OF EARNINGS TO FIXED CHARGES
CAPITALIZATION
SELECTED HISTORICAL CONSOLIDATED FINANCIAL INFORMATION
DESCRIPTION OF OTHER INDEBTEDNESS
THE EXCHANGE OFFER
DESCRIPTION OF THE NOTES
UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS
PLAN OF DISTRIBUTION
LEGAL MATTERS
EXPERTS