The Registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until this registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The address, including zip code, and telephone number, including area code, of the principal executive office of each guarantor registrant listed above is the same as those of the Registrant, Clean Harbors, Inc.

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission relating to these securities is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

On ~~July 30,~~December 7, 2012, we issued ~~$800.0~~$600.0 million aggregate principal amount of ~~5.25%~~5.125% Senior Notes due ~~2020~~2021 (the "old notes") in an unregistered private placement under an indenture dated ~~July 30,~~December 7, 2012.

We are offering to exchange up to ~~$800.0~~$600.0 million aggregate principal amount of ~~5.25%~~5.125% Senior Notes due ~~2020~~2021 (the "new notes") that we have registered under the Securities Act of 1933 for up to all of the ~~$800.0~~$600.0 million aggregate principal amount of outstanding old notes. This prospectus refers to the new notes and the old notes collectively as the "notes." The old 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, and such~~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.~~prospectus in exchange for the old notes and related guarantees.

See "Risk Factors" beginning on page 9 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.

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 $"), all dollar amounts in this prospectus are in U.S. dollars ($).

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.

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:


Ranking		The old notes are, and the new notes will be, our and the guarantors' unsecured senior obligations. The old notes and the new notes rank equally with our and the guarantors' existing and future senior obligations and will rank 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.

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		As of ~~June 30,~~December 31, 2012, we and our guarantor subsidiaries had no outstanding loans under our revolving credit facility, but we then had ~~$86.5~~$132.6 million of outstanding letters of credit and ~~$10.8~~$8.0 million of 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 our capital lease obligations to the extent of the value of the assets securing such secured debt. Furthermore, our non-guarantor subsidiaries had as of ~~June 30,~~December 31, 2012 approximately ~~$167.4~~$211.3 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 ~~August~~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 ~~August~~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."
		At any time prior to ~~August~~December 1, ~~2016,~~2015, we may also redeem up to 35% of the aggregate principal amount of all notes issued under the indenture with the net proceeds of certain equity offerings at a redemption price equal to ~~105.250%~~105.125% of the principal amount of the notes plus accrued and unpaid interest to the date of redemption. We may make that redemption only if, after the redemption, at least 65% of the aggregate principal amount of all notes issued under the indenture remains outstanding.
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;

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		• 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 has been no public market for the old notes. Despite our registration of the new notes that we are offering in the exchange offer:

•: the initial ~~purchaser~~purchasers of the old notes isare not obligated to make a market in the new notes and any such market-making may be discontinued at any time at the sole discretion of the initial ~~purchaser;~~purchasers; and
•: no significant market for the new notes may develop.

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

•: prevailing interest rates;
•: our operating performance and financial condition;
•: the interest of securities dealers in making a market; and
•: the market for similar securities.

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 ~~June 30,~~December 31, 2012, ~~on an adjusted basis after giving effect to the issuance of the old notes and the discharge of all of our 2016 notes which were outstanding on that date,~~ we and our guarantor subsidiaries had outstanding ~~$800.0 million~~$1.4 billion aggregate principal amount of old notes ~~$10.8~~and 5.25% senior notes due 2020, $8.0 million of capital lease obligations, no revolving loans, and ~~$86.5~~$132.6 million of letters of credit. Our substantial levels of outstanding debt and letters of credit may:

•: adversely impact our ability to obtain additional financing in the future for working capital, capital expenditures, acquisitions or other general corporate purposes or to repurchase the notes from holders upon any change of control;
•: require us to dedicate a substantial portion of our cash flow to the payment of interest on our debt and fees on our letters of credit, which reduces the availability of our cash flow to fund working capital, capital expenditures, acquisitions and other general corporate purposes;
•: subject us to the risk of increased sensitivity to interest rate increases based upon variable interest rates, including our borrowings (if any) under our revolving credit facility;
•: increase the possibility of an event of default under the financial and operating covenants contained in our debt instruments; and
•: limit our ability to adjust to rapidly changing market conditions, reduce our ability to withstand competitive pressures and make us more vulnerable to a downturn in general economic conditions of our business than our competitors with less debt.

Our ability to make scheduled payments of principal or interest with respect to our debt, including the notes, any revolving loans and our 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 are 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 ~~June 30, 2012,~~January 17, 2013 (the effective date of our most recent amended and restated credit agreement), up to an additional approximately ~~$163.5~~$267.4 million for purposes of additional borrowings and letters of credit. The indenture

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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:

•: incur or guarantee additional indebtedness (including, for this purpose, reimbursement obligations under letters of credit) or issue 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.

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. ~~On June 30,~~As of December 31, 2012, our non-guarantor subsidiaries had approximately ~~$167.4~~$211.3 million of total liabilities (excluding intercompany liabilities and debt) and held approximately ~~51.0%~~37.3% of our total assets (excluding intercompany ~~receivables)~~receivables and debt), and for the ~~six months~~year ended ~~June 30,~~December 31, 2012, our non-guarantor subsidiaries generated approximately ~~45.7%~~44.1% 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 our 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 ~~June 30,~~December 31, 2012, we had no loans and ~~$86.5~~$132.6 million of letters of credit outstanding under our revolving credit facility and ~~$10.8~~$8.0 million of capital lease obligations. On ~~June 30, 2012,~~January 17, 2013 (the effective date of our most recent amended and restated credit agreement), we also had ~~$163.5~~$267.4 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 idebt, 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:

(1): fair consideration or reasonably equivalent value was not received in exchange for the obligation; and

(2)

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~~(2)~~ at the time the obligation was incurred, the obligor:

•: was insolvent or rendered insolvent by reason of the obligation;
•: was engaged in a business or transaction for which its remaining assets constituted unreasonably small capital; or
•: intended to incur, or believed that it would incur, debts beyond its ability to pay them as the debts matured.

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:

•: the sum of its debts, including contingent liabilities, is greater than the saleable value of all of its assets at a fair valuation;
•: the present fair saleable value of its assets is less than the amount that would be required to pay its probable liability on its existing debts, including contingent liabilities, as they become absolute and matured; or
•: it could not pay its debts as they become due.

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

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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.

There is no established trading market for the notes. If an actual trading market does not develop for the notes, you may not be able to resell them quickly for the price that you paid or at all.

There is no established trading market for the notes and we do not intend to apply for the notes to be listed on any securities exchange or to arrange for any quotation on any automated dealer quotation systems. The initial ~~purchaser has~~purchasers have advised us that ~~it intends~~they intend to make a market in the notes, but ~~it is~~they are not obligated to do so. The initial ~~purchaser~~purchasers may discontinue any market-making in the notes ~~and~~ at any time, in ~~its~~their sole discretion. As a result, we cannot assure you as to the liquidity of any trading market for the notes. We also cannot assure you that you will be able to sell your notes at a particular time or at all, or that the prices that you receive when you sell them will be favorable. If no active trading market develops, you may not be able to resell your notes at their fair market value, or at all.

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

•: prevailing interest rates;
•: our operating performance and financial condition;
•: the interest of securities dealers in making a market; and
•: the market for similar securities.

Historically, the market for non-investment grade debt has been subject to disruptions that have caused volatility in prices of securities similar to the notes. It is possible that the market for the notes will be subject to disruptions. Any disruptions may have a negative effect on noteholders, regardless of our prospects and financial performance.

Risks Affecting Both Our Environmental Services and Energy and Industrial Services Businesses

Our businesses are subject to operational and safety risks.

Provision of both environmental services and energy and industrial services to our customers 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

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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.

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Our businesses are subject to significant competition.

We compete with a large number of companies, which range from large public companies to small operators that provide most of the same or similar services to those we offer. The 2008-2010 downturn in economic conditions, particularly with respect to manufacturing and oil and gas exploration and production, caused increased competition for market share. This competition resulted and could further result in lower prices and reduced gross margins for our services and negatively affect our ability to grow or sustain our current revenue and profit levels in the future.

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.

Future conditions might require us to make substantial write-downs in our assets, which would adversely affect our balance sheet and results of operations.

Periodically, we review our long-lived tangible and intangible assets other than goodwill 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 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. At the end of each of 2012, 2011 ~~2010~~ and ~~2009,~~2010, we determined that no asset write-downs were required; however, if conditions in either the environmental services or energy and industrial services businesses were to deteriorate significantly, 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 rates 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 ~~2011,~~2012, we recorded ~~42%~~44% 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. We manage these risks through normal operating and financing activities. We cannot be certain, however, that we will be successful in reducing the risks inherent in exposures to foreign currency fluctuations.

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If we are unable to successfully integrate the businesses and operations of Safety-Kleen and our other recent and any future acquisitions and realize synergies in the expected time frame, our future results would be adversely affected.

We have in the past significantly increased the size of our Company and the types of services we offer to our customers through acquisitions. Since December 31, 2008, we have acquired two public companies (Eveready Inc. in July 2009, and Peak Energy Services Ltd. in June 2011) and 1115 private

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companies (including ~~ten~~six private companies acquired ~~since 2009)~~during 2010, 2011 and 2012). The largest was our acquisition of Safety-Kleen, Inc., a private company, and its subsidiaries (collectively, "Safety-Kleen"), which we purchased on December 28, 2012 for approximately $1.3 billion. We anticipate that we will likely make additional acquisitions in the future.

Much of the potential benefit of such completed and potential future acquisitions will depend on our integration of the businesses and operations of the acquired companies into our business and operations through implementation of appropriate management and financial reporting systems and controls. We may experience difficulties in such integration, and the integration process may be costly and time-consuming. Such integration will require the focused attention of both Clean Harbors' and acquired companies' management teams, including a significant commitment of their time and resources. The need for both Clean Harbors' and their managements to focus on integration matters could have a material impact on the revenues and operating results of the combined company. The success of the acquisitions will depend, in part, on the combined company's ability to realize the anticipated benefits from combining the businesses of Clean Harbors and the acquired companies through cost reductions in overhead, greater efficiencies, increased utilization of support facilities and the adoption of mutual best practices. To realize these anticipated benefits, however, the businesses of Clean Harbors and the acquired companies must be successfully combined.

If the combined company is not able to achieve these objectives, the anticipated benefits to us of the acquisitions may not be realized fully or at all or may take longer to realize than expected. It is possible that the integration processes could result in the loss of key employees, as well as the disruption of each company's ongoing business, failure to implement the business plan for the combined company, unanticipated issues in integrating operating, logistics, information, communications and other systems, unanticipated changes in applicable laws and regulations, operating risks inherent in our business or inconsistencies in standards, controls, procedures and policies or other unanticipated issues, expenses and liabilities, any or all of which could adversely affect our ability to maintain relationships with our and the acquired companies' customers and employees or to achieve the anticipated benefits of the acquisitions.

Our acquisitions may expose us to unknown liabilities.

Because we have acquired, and expect to acquire, all the outstanding common shares of most of the companies we have previously acquired or may acquire in the future, including our acquisition in December 2012 of Safety-Kleen, Inc., our investments 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 there are unknown liabilities or other obligations, including contingent liabilities, our business could be ~~materially~~adversely affected. We may learn additional information about the acquired companies that adversely affects us, such as unknown liabilities or other 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.

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Risks Particularly Affecting Our Environmental Services Business

We assumed significant environmental liabilities as part of our past acquisitions and may assume additional such liabilities as part of future acquisitions. Our financial condition and results of operations would be adversely affected if we were required to pay such liabilities more rapidly or in greater amounts than we now estimate or may estimate in connection with future acquisitions.

We have accrued environmental liabilities valued as of ~~June 30,~~December 31, 2012, at ~~$167.5~~$221.5 million, substantially all of which we assumed in connection with our acquisitions of substantially all of the assets of the Chemical Services Division, or "CSD," of Safety-Kleen Corp. in 2002, Teris LLC in 2006, ~~and~~ one of two solvent recycling facilities we purchased from Safety-Kleen Systems, Inc. in ~~2008.~~2008 and the remaining Safety-Kleen facilities acquired as part of our acquisition of Safety-Kleen in 2012. 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

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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.

If we are 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 ~~June 30,~~December 31, 2012, our total estimated closure and post-closure costs requiring financial assurance by regulators were ~~$334.8~~$343.1 million for our U.S. facilities and ~~$22.1~~$22.4 million for our Canadian facilities. We have obtained all of the required financial assurance for our facilities (other than those acquired as part of our acquisition of Safety-Kleen) from a qualified insurance company, Zurich Insurance N.A., and its affiliated companies. The closure and post-closure obligations of our U.S. facilities (other than those acquired as part of our acquisition of Safety-Kleen) are insured by an insurance policy written by Steadfast Insurance Company (a unit of Zurich Insurance N.A.), which will expire in 2013. Our Canadian facilities utilize surety bonds provided through Zurich Insurance Company (Canada), which expire at various dates throughout ~~2011.~~2013. In connection with obtaining such insurance and surety bonds, we have provided to Steadfast Insurance Company $73.5 million of letters of credit which we obtained from our lenders under our revolving credit agreement.

As of December 31, 2012, Safety-Kleen's total estimated closure, post-closure costs and corrective action costs requiring financial assurance by regulators were $46.8 million for Safety-Kleen's U.S. facilities and $5.3 million for Safety-Kleen's Canadian facilities. Safety-Kleen has obtained all of the required U.S. financial assurance for its facilities from a qualified insurance company, XL Insurance Company, and its affiliated companies, which will expire in 2013, except for Safety-Kleen's Pennsylvania

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facilities which utilize letters of credit. In connection with obtaining such insurance for its U.S. facilities, Safety-Kleen has provided to XL Insurance Company a $5.0 million letter of credit which Safety-Kleen obtained from its lenders under its revolving credit agreement. Safety-Kleen's Canadian facilities utilize surety bonds provided through Travelers Insurance Company (Canada), which will expire in 2014, and letters of credit.

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 environmental services industry in which we participate is subject to significant economic and business risks.

Our future operating results of our environmental services business 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 experienced significant downsizing and consolidation, realize benefits from cost reduction programs, 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 the 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 hazardous and industrial waste management business is also cyclical

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to the extent that it is dependent upon a stream of waste from cyclical industries such as the chemical and petrochemical, primary metals, paper, furniture and aerospace industries. If those cyclical industries slow significantly, the business that we receive from those industries is likely to slow.

A significant portion of our environmental 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 are significantly 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 significantly 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. In particular, our participation in oil spill response efforts in Yellowstone, Montana generated third party revenues for the year ended December 31, 2011 of $43.6 million, which accounted for approximately 2% of total revenues, and our participation in oil spill response efforts in both the Gulf of Mexico and Michigan generated third party revenues for the year ended December 31, 2010 of $253.0 million, which accounted for approximately 15% of total revenues. We cannot expect such event revenue to reoccur in ~~2012.~~2013.

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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 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

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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 adverse 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 believe these remedial activities will not 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

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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 were to comply with all applicable environmental laws, there is no guarantee that we would be able to obtain the requisite permits from the applicable governmental authorities, and, even if we could, that any permit (and any existing permits we currently hold) will be extended or modified as needed to fit out business needs.

Future changes in environmental regulations may require us to make significant capital expenditures.

Changes in environmental regulations can require us to make significant capital expenditures for our facilities. For example, in 2002, the United States Environmental Protection Agency, or "EPA," promulgated Interim Standards of the Hazardous Waste Combustor Maximum Achievable Control Technology, or "MACT," under the Federal Clean Air Act Amendments. These standards established new emissions limits and operational controls on all new and existing incinerators, cement kilns and light-weight aggregate kilns that burn hazardous waste-derived fuels. We have spent approximately $29.6 million since September 7, 2002 in order to bring our Deer Park, Texas and Aragonite, Utah incineration facilities, which we then acquired as part of the CSD assets, and our Kimball, Nebraska facility into compliance with the MACT regulations. Prior to our acquisition in August 2006 of our additional incineration facility in El Dorado, Arkansas, as part of our purchase of all the membership interests in Teris LLC, Teris had spent in excess of $30.0 million in order to bring that facility into compliance with the MACT standards. Future environmental regulations could cause us to make significant additional capital expenditures and adversely affect our results of operations and cash flow.

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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 any of 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 the 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.

Risks Particularly Affecting Our Energy and Industrial Services Business

A large portion of our energy and industrial 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 could adversely affect our business.

Our energy and industrial services business generates well over 50% 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 industrial maintenance and oil and gas production and refining which are less volatile than oil and gas exploration. We also provide significant services to customers in the oil and gas industry operating in the United States or internationally and to customers in other industries such as forestry, mining and manufacturing. However, a major portion of the total revenues of our energy and industrial services business remains dependent on customers in the oil and gas industry operating in Western Canada.

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Accordingly, declines in the general level of oil and gas exploration, production and refining in Western Canada could potentially have significant adverse effects on our total revenues and profitability. Such declines occurred in 2008-2009 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 future 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 decline considerably. 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. Due to the downturn in worldwide economic conditions and in the commodity price of oil and gas which occurred in 2008-2009, certain of our customers have delayed 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.

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Our energy and industrial services business is subject to workforce availability.

Our ability to provide high quality services to our customers is dependent upon our ability to attract and retain well-trained, experienced employees. Prior to 2008, the oil and gas services industry in Western Canada experienced for several years high demand for, and a corresponding shortage of, quality employees resulting, in particular, in employment of a significant number of employees from Eastern Canada on a temporary basis. Although the 2008-2009 downturn in the oil and gas industry increased the pool of quality employees available to meet our customer commitments, the subsequent improvement during 2010 - 2011 of conditions in the oil and gas industry has increased, and any such improvement which may occur in the future would likely increase, competition for experienced employees.

21Additional Risks Relating to Our Recent Acquisition of Safety-Kleen

In addition to the risks described above which are applicable to our environmental services and energy and industrial services businesses (as those businesses were expanded by our acquisition of Safety-Kleen on December 28, 2012), our acquisition of Safety-Kleen resulted in our becoming subject to certain additional risks, including in the particular the following:

Safety-Kleen's revenues are relatively concentrated among a small number of its largest customers.

In 2012, Safety-Kleen's ten largest customers accounted for approximately 24% of its total revenues and its largest customer accounted for approximately 7% of its total revenues. If one or more of Safety-Kleen's significant customers were to cease doing business with Safety-Kleen or significantly reduce or delay the purchase of products or services from it, our business, financial condition and results of operations could be materially and adversely affected. In addition, Safety-Kleen is subject to credit risk associated with the concentration of its accounts receivable from its customers. None of Safety-Kleen's accounts receivable are covered by collateral or credit insurance. If one or more of its significant customers or if any material portion of Safety-Kleen's other customers were to fail to pay Safety-Kleen on a timely basis, our business, financial condition and results of operations could be

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materially and adversely affected. Additionally, future consolidation of Safety-Kleen's customers or additional concentration of market share among its customers may increase its credit risk.

Fluctuations in oil prices may have a negative effect on Safety-Kleen's future results of operations derived from its oil re-refining and recycling business.

A significant portion of Safety-Kleen's business involves collecting used oil from certain of its 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 Safety-Kleen does not currently have the capacity to re-refine, or "RFO," to other customers. The prices at which Safety-Kleen sells its re-refined oil and RFO are affected by changes in the reported spot market prices of oil. If applicable rates increase or decrease, Safety-Kleen typically will charge a higher or lower corresponding price for its re-refined oil and RFO. The price at which Safety-Kleen sells its 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 Safety-Kleen's RFO. The cost to collect used oil, including the amounts Safety-Kleen must pay to obtain used oil and the fuel costs of its oil collection fleet, typically also increases or decreases when the relevant indices increase or decrease. However, even though the prices Safety-Kleen can charge for its 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 Safety-Kleen's costs to collect and re-refine used oil and process RFO increase it will be able to increase the prices it charges for its re-refined oil and RFO to cover such increased costs or that the costs to collect and re-refine used oil and process RFO will decline when the prices it can charge for re-refined oil and RFO decline. These risks are exacerbated when there are rapid fluctuations in these oil indices.

The price at which Safety-Kleen purchases used oil from its large customers through its oil collection services is generally fixed for a period of time by contract, in some cases for up to 90 days. Because the price Safety-Kleen pays for a majority of its used oil is fixed for a period of time and it can take up to eight weeks to transport, re-refine and blend collected used oil into Safety-Kleen's finished blended lubricating oil products, Safety-Kleen typically experiences margin contraction during periods when the applicable index rates decline. If the index rates decline rapidly, Safety-Kleen may be locked into paying higher than market prices for used oil during these contracted periods while the prices it can charge for its finished oil products decline. If the prices Safety-Kleen charges for its finished oil products and the costs to collect and re-refine used oil and process RFO do not move together or in similar magnitudes, Safety-Kleen's profitability may be materially and negatively impacted.

Safety-Kleen has entered into several commodity derivatives since 2011, which are comprised of cashless collar contracts related to crude oil prices, in each case, where Safety-Kleen sold a call option to a bank and then purchased a put option from the same bank, in order to manage against significant fluctuations in crude oil prices, which are closely correlated with indices discussed above. However, these commodity derivatives are designed to only mitigate Safety-Kleen's exposure to declines in these oil indices below a price floor, and Safety-Kleen will not be protected and its profitability may be materially and negatively impacted by declines above the price floor. In addition, these commodity derivatives will limit Safety-Kleen's potential benefit when these oil indices increase above a price cap because Safety-Kleen will be required to make payments in that circumstance. Furthermore, Safety-Kleen's current commodity derivatives expire at various intervals, and there is no assurance that we will be able to enter into commodity derivatives in the future with acceptable terms.

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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. In fiscal years 2012 and 2011, Safety-Kleen paid a total of approximately $365,000 and $190,000, respectively, for such fines, including fines arising in previous years. In 2009, Safety-Kleen recorded as an expense a $15.0 million settlement with the South Coast Air Quality Management District, or "SCAQMD," in southern California and other regulatory agencies for alleged civil violations of SCAQMD Rule 1171, which prohibits the use of solvent, except for certain exempt uses, in the district. Safety-Kleen paid this settlement and is currently in compliance with SCAQMD Rule 1171. However, in the future, 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. In particular, there has been a regulatory-driven shift away from solvents having higher volatile organic compounds, or "VOC," as evidenced by the recent move of the Ozone Transport Commission representing several states to reduce the VOC limits for various products, including solvent used for parts cleaning or with paint-gun cleaning equipment. 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 costs, 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 as a defendant in various product liability lawsuits in various courts and jurisdictions throughout the United States from time to time. As of December 31, 2012, Safety-Kleen was involved in approximately 64 proceedings (including cases which have been settled but not formally dismissed) wherein persons claimed 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 vigorously defends itself and the safety of its products against all of these claims (and we intend to continue defending 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 is decided unfavorably against Safety-Kleen and the plaintiffs are awarded punitive damages, or if the claim is one for which insurance coverage may not be available, our financial condition and results of operations could be materially and

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adversely affected. Additionally, if one or more of these claims were decided unfavorably against Safety-Kleen, such outcome may encourage even more lawsuits against us.

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 is not able to retain these providers or obtain its requests from these providers, 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.

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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.

	~~Six~~ ~~Months~~ ~~Ended~~ ~~June 30,~~				Year Ended December 31,

	2012		2011		~~2011~~		2010		2009		2008		~~2007~~
Ratio of earnings to fixed charges(1)		~~4.1x~~		~~4.7x~~3.3X		5.0x		6.2x		3.6x		6.0x		~~4.1x~~

(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.

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CAPITALIZATION

The following table sets forth our consolidated cash and cash equivalents, long-term debt (including current portion), and stockholders' equity as of June 30, 2012, on an actual basis and on an as adjusted basis to reflect (i) the sale of the $800.0 million aggregate principal amount of old notes on July 30, 2012, (ii) our discharge through redemptions and tender offer purchases completed between July 13, 2012 and August 15, 2012 of all of the $520.0 million aggregate principal amount of our 2016 notes which were outstanding on June 30, 2012, and (iii) our payment of related fees and expenses.December 31, 2012. This table should be read in conjunction with "Use of Proceeds," "Selected Historical Consolidated Financial Information," and "Description of ~~Revolving Credit Facility"~~Other Indebtedness" elsewhere in this prospectus and our historical financial statements and the notes thereto incorporated by reference into this prospectus.

	Actual			As Adjusted			December 31, 2012

	June 30, 2012
	(in thousands)						(in thousands)
Cash and cash equivalents	$	296,758		$	466,501		$	229,836

Long-term debt, including current portion:
Revolving credit facility(1)	$	—		$	—		$	—
Capital lease obligations		10,804			10,804			7,971
Senior secured notes due 2016(2)		520,000			—
Senior notes due 2020		—			800,000
Senior Notes due 2020								800,000
Senior Notes due 2021								600,000

Total long-term debt, including current portion(3)		530,804			810,804
Total long-term debt, including current portion(2)								1,407,971

Stockholders' equity:
Common stock, $.01 par value;
Authorized 80,000,000 shares; issued and outstanding 53,319,029 shares		533			533
Authorized 80,000,000 shares; issued and outstanding 60,385,453 shares								604
Shares held under employee participation plan		(469	)		(469	)		(469	)
Additional paid-in capital		504,667			504,667			880,979
Accumulated other comprehensive income		29,076			29,076			49,632
Accumulated earnings(4)		427,093			410,220
Accumulated earnings								501,326

Total stockholders' equity		960,900			944,027			1,432,072

Total capitalization	$	1,491,704		$	1,754,831		$	2,840,043

The following selected ~~historical~~ consolidated financial information ~~has~~for the three years ended December 31, 2012 and the consolidated balance sheet information at December 31, 2012 and 2011 have been derived from our audited ~~consolidated balance sheets at December 31, 2011 and 2010 and~~financial statements ~~of income for the five years ended December 31, 2011, and our unaudited balance sheet at June 30, 2012 and statements of income for the six months ended June 30, 2012 and 2011.~~incorporated by reference in this prospectus. This data should be reviewed in conjunction with "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our ~~historical~~audited financial statements and the notes thereto incorporated by reference in this prospectus. We have derived the consolidated financial information for the years ended December 31, 2009 and 2008, and ~~2007 as well as~~ the ~~June 30, 2011~~consolidated balance sheet information at December 31, 2010, 2009 and 2008, from our audited financial statements not incorporated or included herein.


Large accelerated filer ý		Accelerated filer o		Non-accelerated filer o (Do not check if a small reporting company)		Smaller reporting company o

Title of Each Class of Securities to be Registered	Amount to be Registered	Proposed Maximum Offering Price Per Security	Proposed Maximum Aggregate Offering Price(1)	Amount of Registration Fee(2)	Amount to be Registered	Proposed Maximum Offering Price Per Security	Proposed Maximum Aggregate Offering Price(1)	Amount of Registration Fee(2)




5.25% Senior Notes due 2020	$800,000,000	100%	$800,000,000	$91,680.00
5.125% Senior Notes due 2021					$600,000,000	100%	$600,000,000	$81,840.00

Guarantees(3)	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

Exact name of Guarantor Registrants as specified in its charter	Jurisdiction of Incorporation or Organization

Altair Disposal Services, LLC	Delaware	4953	56-2295310
ARC Advanced Reactors and Columns, LLC	Delaware	4953	26-4260688
Baton Rouge Disposal, LLC	Delaware	4953	56-2295315
Bridgeport Disposal, LLC	Delaware	4953	56-2295319
CH International Holdings, LLC	Delaware	4953	47-0942135
Clean Harbors Andover, LLC	Delaware	4953	56-2295323
Clean Harbors Antioch, LLC	Delaware	4953	02-0646441
Clean Harbors Aragonite, LLC	Delaware	4953	02-0646449
Clean Harbors Arizona, LLC	Delaware	4953	56-2295308
Clean Harbors Baton Rouge, LLC	Delaware	4953	56-2295309
Clean Harbors BDT, LLC	Delaware	4953	56-2295313
Clean Harbors Buttonwillow, LLC	Delaware	4953	56-2295316
Clean Harbors Catalyst Technologies, LLC	Delaware	4953	32-0003075
Clean Harbors Chattanooga, LLC	Delaware	4953	56-2295318
Clean Harbors Clive, LLC	Delaware	4953	56-2295229
Clean Harbors Coffeyville, LLC	Delaware	4953	56-2295320
Clean Harbors Colfax, LLC	Delaware	4953	56-2295321
Clean Harbors Deer Park, LLC	Delaware	4953	48-1263743
Clean Harbors Deer Trail, LLC	Delaware	4953	56-2295327
Clean Harbors Development, LLC	Delaware	4953	30-0471576
Clean Harbors Disposal Services, Inc.	Delaware	4953	04-3667165
Clean Harbors El Dorado, LLC	Delaware	4953	94-3401916
Clean Harbors Environmental Services, Inc.	Massachusetts	4953	04-2698999
Clean Harbors Exploration Services, Inc.	Nevada	4953	84-1713357
Clean Harbors Florida, LLC	Delaware	4953	56-2295283
Clean Harbors Grassy Mountain, LLC	Delaware	4953	56-2295286
Clean Harbors Industrial Services, Inc.	Delaware	4953	52-2339707
Clean Harbors Kansas, LLC	Delaware	4953	56-2295290
Clean Harbors Kingston Facility Corporation	Massachusetts	4953	04-3074299
Clean Harbors LaPorte, LLC.	Delaware	4953	48-1263744
Clean Harbors Laurel, LLC	Delaware	4953	56-2295292
Clean Harbors Lone Mountain, LLC	Delaware	4953	56-2295299
Clean Harbors Lone Star Corp.	Delaware	4953	06-1655334
Clean Harbors Los Angeles, LLC	Delaware	4953	56-2295303
Clean Harbors (Mexico), Inc.	Delaware	4953	56-2294684
Clean Harbors of Baltimore, Inc.	Delaware	4953	23-2091580
Clean Harbors of Braintree, Inc.	Massachusetts	4953	04-2507498
Clean Harbors of Connecticut, Inc.	Delaware	4953	06-1025746
Clean Harbors Pecatonica, LLC	Delaware	4953	56-2295314
Clean Harbors PPM, LLC	Delaware	4953	56-2295269
Clean Harbors Recycling Services of Chicago, LLC	Delaware	4953	36-4599645
Clean Harbors Recycling Services of Ohio, LLC	Delaware	4953	36-4599643
Clean Harbors Reidsville, LLC	Delaware	4953	56-2295199
Clean Harbors San Jose, LLC	Delaware	4953	56-2295202
Clean Harbors Services, Inc.	Massachusetts	4953	06-1287127
Clean Harbors Tennessee, LLC	Delaware	4953	56-2295205

~~Exact name of Guarantor Registrants as specified in its charter~~	~~Jurisdiction of~~ ~~Incorporation or~~ ~~Organization~~

Clean Harbors Westmorland, LLC	Delaware	4953	56-2295208
Clean Harbors White Castle, LLC	Delaware	4953	56-2295210
Clean Harbors Wilmington, LLC	Delaware	4953	13-4335799

Exact name of Guarantor Registrants as specified in its charter	Jurisdiction of Incorporation or Organization

Crowley Disposal, LLC	Delaware	4953	06-1655356
Disposal Properties, LLC	Delaware	4953	56-2295213
DuraTherm, Inc.	Delaware	4953	26-1821662
GSX Disposal, LLC	Delaware	4953	56-2295215
Hilliard Disposal, LLC	Delaware	4953	56-2295217
Murphy's Waste Oil Service, Inc.	Massachusetts	4953	04-2490849
Peak Energy Services USA, Inc.	Delaware	4953	98-0429483
Plaquemine Remediation Services, LLC	Delaware	4953	56-2295280
Roebuck Disposal, LLC	Delaware	4953	56-2295219
Safety-Kleen Envirosystems Company	California	4953	94-2764195
Safety-Kleen Envirosystems Company of Puerto Rico, Inc.	Indiana	4953	35-1283524
Safety-Kleen, Inc.	Delaware	4953	90-0127028
Safety-Kleen International, Inc.	Delaware	4953	36-3396234
Safety-Kleen Systems, Inc.	Wisconsin	4953	39-6090019
Sanitherm USA, Inc.	Delaware	4953	68-0678615
Sawyer Disposal Services, LLC	Delaware	4953	56-2295224
Service Chemical, LLC	Delaware	4953	56-2295322
SK Holding Company, Inc.	Delaware	4953	90-0127037
Spring Grove Resource Recovery, Inc.	Delaware	4953	76-0313183
The Solvents Recovery Service of New Jersey, Inc.	New Jersey	4953	22-1293778
Tulsa Disposal, LLC	Delaware	4953	56-2295227


Massachusetts (State or other jurisdiction of incorporation or organization)		4953 (Primary Standard Industrial Classification Code Number)		04-2997780 (I.R.S. Employer Identification Number)

		Page

SUMMARY			1
RISK FACTORS			9
USE OF PROCEEDS			2225
RATIO OF EARNINGS TO FIXED CHARGES			2225
CAPITALIZATION			2326
SELECTED HISTORICAL CONSOLIDATED FINANCIAL INFORMATION			2427
DESCRIPTION OF ~~REVOLVING CREDIT FACILITY~~OTHER INDEBTEDNESS			2731
THE EXCHANGE OFFER			2833
DESCRIPTION OF THE NOTES			3843
UNITED STATES FEDERAL INCOME AND ESTATE TAX CONSIDERATIONS			8086
PLAN OF DISTRIBUTION			8490
LEGAL MATTERS			8490
EXPERTS			8590


Background		On ~~July 30,~~December 7, 2012, 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., Merrill Lynch, Pierce, Fenner & Smith Incorporated and Credit Suisse (USA) LLC, the initial ~~purchaser~~purchasers 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 ~~$800.0~~$600.0 million aggregate principal amount of our new notes which have been registered under the Securities Act for up to all of the ~~$800.0~~$600.0 million aggregate principal amount of our old notes. You may tender old notes only in denominations of $2,000 and any integral ~~multiples~~multiple of ~~$1,000 principal amount.~~$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.
		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~~purchasers of the old notes ~~has~~have informed us that ~~it intends~~they intend to make a market in the new notes, ~~it is~~they are 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 , ~~2012~~2013 unless we extend the exchange offer.
Conditions to the Exchange Offer		The exchange offer is subject to limited, customary conditions, which we may waive.
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."
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 "United States Federal Income and Estate 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."


Issuer		Clean Harbors, Inc. (the "Issuer").
New Notes Offered		$~~800,000,000~~600,000,000 aggregate principal amount of ~~5.25%~~5.125% Senior Notes due ~~2020.~~2021.
Maturity Date		~~August~~June 1, ~~2020.~~2021.
Interest Payments		Interest on the notes is payable semi-annually in arrears on ~~February~~June 1 and ~~August~~December 1 of each year, commending on ~~February~~June 1, 2013.
Guarantees		The old notes are, and the new notes will be, fully and unconditionally and jointly and severally guaranteed on a senior unsecured basis by substantially all of our existing and future domestic 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. The old notes are not, and the new notes will not be, guaranteed by our Canadian and other foreign subsidiaries.

	2012		2011			2011			2010			2009			2008		2007			Year Ended December 31,

	Six Months Ended June 30,					Year Ended December 31,
	(in thousands)																			2012			2011			2010			2009			2008
Net income	$	55,441		51,886		$	127,252		$	130,515		$	36,686		$	57,486	$	44,198		$	129,674		$	127,252		$	130,515		$	36,686		$	57,486
Accretion of environmental liabilities		4,921		4,796			9,680			10,307			10,617			10,776		10,447			9,917			9,680			10,307			10,617			10,776
Depreciation and amortization		75,494		52,396			122,663			92,473			64,898			44,471		37,590			161,646			122,663			92,473			64,898			44,471
Other (income) expense		374		(5,767	)		(6,402	)		(2,795	)		(259	)		119		(135	)
Other expense (income)																					802			(6,402	)		(2,795	)		(259	)		119
Loss on early extinguishment of debt		—		—			—			2,294			4,853			5,473		—			26,385			—			2,294			4,853			5,473
Interest expense, net		22,240		17,120			39,389			27,936			15,999			8,403		13,157			47,287			39,389			27,936			15,999			8,403
Provision for income taxes		31,179		28,387			57,426			56,756			26,225			36,491		28,040
(Benefit) provision for income taxes																					(1,944	)		57,426			56,756			26,225			36,491
Income from discontinued operations, net of tax		—		—			—			(2,794	)		(1,439	)		—		—			—			—			(2,794	)		(1,439	)		—

Adjusted EBITDA	$	189,649	$	148,818		$	350,008		$	314,692		$	157,580		$	163,219	$	133,297		$	373,767		$	350,008		$	314,692		$	157,580		$	163,219


By Hand or Overnight Courier:		By Facsimile Transmission:
U.S. Bank National Association		(651) 495-8158
60 Livingston Avenue, 1^st 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

Year

2016	102.625	%	102.563	%
2017	101.313	%	101.281	%
2018 and thereafter	100.000	%	100.000	%

~~Exhibit No.~~			~~Description of Exhibit~~

	~~3.1A~~		~~Restated Articles of Organization of Clean Harbors, Inc. (incorporated by reference to Exhibit 3.1A to the Registrant's Report on Form 8-K filed on May 19, 2005 (File No. 001-34223)).~~

	~~3.1B~~		Articles of Amendment [as filed on May 9, 2011] to Restated Articles of Organization of Clean Harbors, Inc. (incorporated by reference to Exhibit 3.1B to the Registrant's Report on Form 8-K filed on May 12, 2011 (File No. 001-34223)).

	~~3.4B~~		~~Amended and Restated By-Laws of Clean Harbors, Inc. (incorporated by reference to Exhibit 3.4C to the Registrant's Report on Form 8-K filed on December 6, 2011 (File No. 001-34223)).~~

	~~4.1~~		Indenture dated as of July 30, 2012, by and among Clean Harbors, Inc., the Guarantors named therein and U.S. Bank National Association, as Trustee, relating to the 5.25% Senior Notes due 2020, including the form of 5.25% Senior Note due 2020 (incorporated by reference to Exhibit 4.40 to the Registrant's Report on Form 8-K filed on July 30, 2012 (File No. 001-34223)).

	~~4.2~~		Registration Rights Agreement dated July 30, 2012 between Clean Harbors, Inc., the domestic subsidiaries of Clean Harbors, Inc. as guarantors, and Goldman Sachs & Co. (incorporated by reference to Exhibit 4.41 to the Registrant's Report on Form 8-K filed on July 30, 2012 (File No. 001-34223)).

	At June 30,				At December 31,										At December 31,

	2012		2011		2011		2010		2009		2008		2007		2012(1)		2011		2010		2009		2008
	(in thousands)														(in thousands)
*Balance Sheet Data:*
Working capital	$	504,187	$	540,942	$	510,126	$	446,253	$	386,930	$	307,679	$	169,585	$	517,741	$	510,126	$	446,253	$	386,930	$	307,679
Goodwill		135,962		88,511		122,392		60,252		56,085		24,578		21,572		593,771		122,392		60,252		56,085		24,578
Total assets		2,122,214		1,965,080		2,085,803		1,602,475		1,401,068		898,336		769,888		3,825,806		2,085,803		1,602,475		1,401,068		898,336
Long-term obligations (including current portion)~~(4)~~(5)		534,285		540,623		538,888		278,800		301,271		53,630		123,483		1,407,971		538,888		278,800		301,271		53,630
Stockholders' equity(3)		960,900		857,368		900,987		780,827		613,825		429,045		202,897		1,432,072		900,987		780,827		613,825		429,045

	Six Months Ended June 30,						Year Ended December 31,															Year Ended December 31,

	2012			2011			2011			2010			2009			2008			2007			2012			2011			2010			2009			2008
Adjusted EBITDA	$	189,649		$	148,818		$	350,008		$	314,692		$	157,580		$	163,219		$	133,297		$	373,767		$	350,008		$	314,692		$	157,580		$	163,219
Interest expense, net		(22,240	)		(17,120	)		(39,389	)		(27,936	)		(15,999	)		(8,403	)		(13,157	)		(47,287	)		(39,389	)		(27,936	)		(15,999	)		(8,403	)
Provision for income taxes		(31,179	)		(28,387	)		(57,426	)		(56,756	)		(26,225	)		(36,491	)		(28,040	)
Benefit (provision) for income taxes																							1,944			(57,426	)		(56,756	)		(26,225	)		(36,491	)
Income from discontinued operations, net of tax		—			—			—			2,794			1,439			—			—			—			—			2,794			1,439			—
Allowance for doubtful accounts		405			402			759			1,043			1,006			267			(418	)		1,213			759			1,043			1,006			267
Amortization of deferred financing costs and debt discount		753			898			1,572			2,921			1,997			1,915			1,940			1,793			1,572			2,921			1,997			1,915
Change in environmental liability estimates		(3,095	)		(773	)		(2,840	)		(8,328	)		(4,657	)		(2,047	)		597			(8,458	)		(2,840	)		(8,328	)		(4,657	)		(2,047	)
Deferred income taxes		(510	)		819			37,836			4,919			4,830			3,197			(7,492	)		34,163			37,836			4,919			4,830			3,197
Stock-based compensation		3,616			2,880			8,164			7,219			968			3,565			4,799			7,494			8,164			7,219			968			3,565
Excess tax benefit of stock-based compensation		(1,122	)		(1,617	)		(3,352	)		(1,751	)		(481	)		(3,504	)		(6,386	)		(2,556	)		(3,352	)		(1,751	)		(481	)		(3,504	)
Income tax benefits related to stock option exercises		1,121			1,617			3,347			1,739			474			3,534			6,427			2,546			3,347			1,739			474			3,534
Eminent domain compensation		—			3,354			3,354			—			—			—			—			—			3,354			—			—			—
Gain on sale of businesses		—			—			—			(2,678	)		—			—			—			—			—			(2,678	)		—			—
Prepayment penalty on early extinguishment of debt		—			—			—			(900	)		(3,002	)		(3,552	)		—			(21,044	)		—			(900	)		(3,002	)		(3,552	)
Environmental expenditures		(3,787	)		(5,564	)		(11,319	)		(10,236	)		(8,617	)		(14,268	)		(6,511	)		(11,191	)		(11,319	)		(10,236	)		(8,617	)		(14,268	)
Changes in assets and liabilities, net of acquisitions:
Changes in assets and liabilities, net of acquisitions
Accounts receivable		54,117			18,063			(65,210	)		(49,411	)		(11,429	)		17,221			(19,142	)		54,373			(65,210	)		(49,411	)		(11,429	)		17,221
Inventories and supplies																							(12,871	)		(11,696	)		(3,129	)		(14,512	)		(4,542	)
Other current assets		15,657			(5,252	)		(36,761	)		(10,550	)		1,093			5,529			(2,693	)		9,334			(25,065	)		(7,421	)		15,605			10,071
Accounts payable		(16,904	)		(33,024	)		(8,116	)		38,553			5,050			(17,763	)		(4,603	)		5,930			(8,116	)		38,553			5,050			(17,763	)
Other current liabilities		(10,707	)		(9,485	)		(1,096	)		18,774			(10,757	)		(2,829	)		21,377			(64,785	)		(1,096	)		18,774			(10,757	)		(2,829	)

Net cash from operating activities	$	175,774		$	75,629		$	179,531		$	224,108		$	93,270		$	109,590		$	79,995		$	324,365		$	179,531		$	224,108		$	93,270		$	109,590

		~~Description of Exhibit~~

~~99.3~~	*	~~Form of Letter to Registered Holders and DTC Participants.~~

~~99.4~~	*	~~Form of Letter to Clients.~~

~~99.5~~	*	~~Form of Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9.~~


		Clean Harbors, Inc.
		By:		/s/ ~~ALAN S. MCKIM~~JAMES M. RUTLEDGE ~~Alan S. McKim~~James M. Rutledge Vice Chairman, President and Chief ~~Executive~~Financial Officer

		~~Description of Exhibit~~

~~4.3~~		Third Amended and Restated Credit Agreement dated as of May 31, 2011 among Clean Harbors, Inc., as the U.S. Borrower, Clean Harbors Industrial Services Canada, Inc., as the Canadian Borrower, Bank of America, N.A., as Administrative Agent, and the Lenders party thereto (incorporated by reference to Exhibit 4.33E to the Registrant's Report on Form 8-K filed on June 3, 2011 (File No. 001-34223)).

~~4.4~~		Guarantee (U.S. Domiciled Loan Parties—U.S. Facility Obligations) dated as of May 31, 2011 executed by the U.S. Domiciled Subsidiaries of Clean Harbors, Inc. named therein in favor of Bank of America, N.A., as Agent for itself and the other U.S. Facility Secured Parties (incorporated by reference to Exhibit 4.33F to the Registrant's Report on Form 8-K filed on June 3, 2011 (File No. 001-34223)).

~~4.5~~		Guarantee (Canadian Domiciled Loan Parties—Canadian Facility Obligations) dated as of May 31, 2011 executed by the Canadian Domiciled Subsidiaries of Clean Harbors, Inc. named therein in favor of Bank of America, N.A., as Agent for itself and the other Canadian Facility Secured Parties (incorporated by reference to Exhibit 4.33G to the Registrant's Report on Form 8-K filed on June 3, 2011 (File No. 001-34223)).

~~4.6~~		Guarantee (U.S. Domiciled Loan Parties—Canadian Facility Obligations) dated as of May 31, 2011 executed by Clean Harbors, Inc. and the U.S. Domiciled Subsidiaries of Clean Harbors, Inc. named therein in favor of Bank of America, N.A., as Agent for itself and the other Canadian Facility Secured Parties (incorporated by reference to Exhibit 4.33H to the Registrant's Report on Form 8-K filed on June 3, 2011 (File No. 001-34223)).

~~4.7~~		Security Agreement (U.S. Domiciled Loan Parties) dated as of May 31, 2011 among Clean Harbors, Inc., as the U.S. Borrower and a Grantor, the subsidiaries of Clean Harbors, Inc. listed on Annex A thereto or that thereafter become a party thereto as Grantors, and Bank of America, N.A., as Agent (incorporated by reference to Exhibit 4.33I to the Registrant's Report on Form 8-K filed on June 3, 2011 (File No. 001-34223)).

~~4.8~~		Security Agreement (Canadian Domiciled Loan Parties) dated as of May 31, 2011 among Clean Harbors Industrial Services Canada, Inc., as the Canadian Borrower and a Grantor, the Canadian subsidiaries of Clean Harbors, Inc. listed on Annex A thereto or that thereafter become a party thereto as Grantors, and Bank of America, N.A., as Agent (incorporated by reference to Exhibit 4.33J to the Registrant's Report on Form 8-K filed on June 3, 2011 (File No. 001-34223)).

~~5.1~~	*	~~Opinion of Davis, Malm & D'Agostine, P.C.~~

~~12.1~~	*	~~Statement regarding computation of ratio of earnings to fixed charges.~~

~~21.1~~	*	~~Subsidiaries of the Registrant.~~

~~23.1~~	*	~~Consent of Deloitte & Touche LLP.~~

~~23.2~~	*	~~Consent of Davis, Malm & D'Agostine, P.C. (included in Exhibit 5.1).~~

24	*	~~Powers of Attorney (See pages II-4 through II-18 of this Registration Statement).~~

~~25.1~~	*	~~Statement of Eligibility and Qualification under the Trust Indenture Act of 1939 of U.S. Bank National Association, as Trustee, on Form T-1, relating to the Registrant's 5.25% Senior Notes due 2020.~~

~~99.1~~	*	~~Form of Letter of Transmittal.~~

~~99.2~~	*	~~Form of Notice of Guaranteed Delivery.~~

Signature	Title	Date


/s/ ALAN S. MCKIM Alan S. McKim	Chairman of the Board of Directors and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Vice Chairman of the Board of Directors, Chief Financial Officer and President	~~August 30, 2012~~
~~/s/ ROBERT E. GAGNON~~ ~~Robert E. Gagnon~~	~~Executive Vice President, Chief Financial Officer and Treasurer~~	~~August 30, 2012~~April 3, 2013
/s/ JOHN R. BEALS John R. Beals	Senior Vice President, Controller and Chief Accounting Officer	~~August 30, 2012~~April 3, 2013
/s/ EUGENE BANUCCI Eugene Banucci	Director	~~August 30, 2012~~April 3, 2013

Signature	Title	Date


/s/ JOHN P. DEVILLARS John P. DeVillars	Director	~~August 30, 2012~~April 3, 2013
/s/ EDWARD G. GALANTE Edward G. Galante	Director	~~August 30, 2012~~April 3, 2013
/s/ JOHN F. KASLOW John F. Kaslow	Director	~~August 30, 2012~~April 3, 2013
/s/ ROD MARLIN Rod Marlin	Director	~~August 30, 2012~~April 3, 2013
/s/ DANIEL J. MCCARTHY Daniel J. McCarthy	Director	~~August 30, 2012~~April 3, 2013
/s/ JOHN T. PRESTON John T. Preston	Director	~~August 30, 2012~~April 3, 2013
/s/ ANDREA ROBERTSON Andrea Robertson	Director	~~August 30, 2012~~April 3, 2013
/s/ THOMAS J. SHIELDS Thomas J. Shields	Director	~~August 30, 2012~~April 3, 2013

Signature	Title	Date


/s/ ERIC W. GERSTENBERG Eric W. Gerstenberg	President and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and ~~Treasurer~~Chief Financial and Accounting Officer	~~August 30, 2012~~April 3, 2013
/s/ ERIC W. GERSTENBERG Eric W. Gerstenberg	Manager	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Manager	~~August 30, 2012~~April 3, 2013


		ARC Advanced Reactors and Columns, LLC
		Clean Harbors Catalyst Technologies, LLC
		By:		/s/ JAMES M. RUTLEDGE James M. Rutledge, Executive Vice President

Signature	Title	Date


/s/ ~~WALLY DUMONT~~DAVID M. PARRY ~~Wally Dumont~~David M. Parry	President and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and ~~Treasurer~~Chief Financial and Accounting Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Manager	~~August 30, 2012~~April 3, 2013
/s/ ~~WALLY DUMONT~~DAVID M. PARRY ~~Wally Dumont~~David M. Parry	Manager	~~August 30, 2012~~April 3, 2013

Name	Title	Date


/s/ JERRY E. CORRELL Jerry E. Correll	President and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and ~~Treasurer~~Chief Financial and Accounting Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Manager	~~August 30, 2012~~April 3, 2013

Name	Title	Date


/s/ WILLIAM J. GEARY William J. Geary	President and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and ~~Treasurer~~Chief Financial and Accounting Officer	~~August 30, 2012~~April 3, 2013
/s/ ERIC W. GERSTENBERG Eric W. Gerstenberg	Manager	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Manager	~~August 30, 2012~~April 3, 2013


		Clean Harbors Disposal Services, Inc. Clean Harbors of Baltimore, Inc. Clean Harbors of Connecticut, Inc. DuraTherm, Inc. Spring Grove Resource Recovery, Inc.
		By:		/s/ JAMES M. RUTLEDGE James M. Rutledge, Executive Vice President

Signature	Title	Date


/s/ ERIC W. GERSTENBERG Eric WW. Gerstenberg	President and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and ~~Treasurer~~Chief Financial and Accounting Officer	~~August 30, 2012~~April 3, 2013
/s/ ERIC W. GERSTENBERG Eric WW. Gerstenberg	Director	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Director	~~August 30, 2012~~April 3, 2013


		Clean Harbors Lone Star Corp. Clean Harbors (Mexico), Inc. Clean Harbors of Braintree, Inc. Clean Harbors Services, Inc.
		By:		/s/ JAMES M. RUTLEDGE James M. Rutledge, Executive Vice President

Signature	Title	Date


/s/ ERIC W. GERSTENBERG Eric W. Gerstenberg	President and Chief Executive Officer	April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and Chief Financial and Accounting Officer	April 3, 2013
/s/ ERIC W. GERSTENBERG Eric W. Gerstenberg	Director	April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Director	April 3, 2013
/s/ ALAN S. MCKIM Alan S. McKim	Director	April 3, 2013

Signature	Title	Date


/s/ MARVIN LEFEBVRE Marvin LeFebvre	President and Chief Executive Officer	April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and Chief Financial and Accounting Officer	April 3, 2013
/s/ DAVID M. PARRY David M. Parry	Director	April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Director	April 3, 2013

Signature	Title	Date


/s/ ~~ERIC W. GERSTENBERG~~BRIAN WEBER ~~Eric W Gerstenberg~~Brian Weber	President and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ ~~ROBERT E. GAGNON~~JAMES M. RUTLEDGE ~~Robert E. Gagnon~~James M. Rutledge	Executive Vice President, Treasurer and Chief Financial and Accounting Officer	~~August 30, 2012~~
~~/s/ ERIC W. GERSTENBERG~~ ~~Eric W Gerstenberg~~	~~Director~~	~~August 30, 2012~~
~~/s/ JAMES M. RUTLEDGE~~ ~~James M. Rutledge~~	~~Director~~	~~August 30, 2012~~April 3, 2013
/s/ ALAN S. MCKIM Alan S. McKim	Director	~~August 30, 2012~~April 3, 2013


		~~Clean Harbors Exploration Services,~~Murphy's Waste Oil Service, Inc.
		By:		/s/ JAMES M. RUTLEDGE James M. Rutledge, Executive Vice President

Signature	Title	Date


/s/ ~~MARVIN LEFEBVRE~~BRIAN WEBER ~~Marvin LeFebvre~~Brian Weber	President and Chief Executive Officer	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Executive Vice President, Treasurer and Chief Financial and Accounting Officer	~~August 30, 2012~~April 3, 2013
/s/ ~~DAVID M. PARRY~~ERIC W. GERSTENBERG ~~David M. Parry~~Eric W. Gerstenberg	Director	~~August 30, 2012~~April 3, 2013
/s/ JAMES M. RUTLEDGE James M. Rutledge	Director	~~August 30, 2012~~April 3, 2013


		~~Clean Harbors Industrial Services, Inc.~~
		~~By:~~		~~/s/ JAMES M. RUTLEDGE~~ ~~James M. Rutledge,~~ ~~Executive Vice President~~

~~Signature~~	~~Title~~	~~Date~~


~~/s/ WALLY DUMONT~~ ~~Wally Dumont~~	~~President~~	~~August 30, 2012~~
~~/s/ ROBERT E. GAGNON~~ ~~Robert E. Gagnon~~	~~Executive Vice President, Treasurer and Chief Financial and Accounting Officer~~	~~August 30, 2012~~
~~/s/ DAVID M. PARRY~~ ~~David M. Parry~~	~~Director~~	~~August 30, 2012~~
~~/s/ JAMES M. RUTLEDGE~~ ~~James M. Rutledge~~	~~Director~~	~~August 30, 2012~~


	~~Clean Harbors Kingston Facility Corporation~~
Peak Energy Services USA, Inc.	~~By:~~	~~/s/ JAMES M. RUTLEDGE~~ ~~James M. Rutledge,~~ ~~Executive Vice President~~

~~Signature~~	~~Title~~	~~Date~~


~~/s/ BRIAN WEBER~~ ~~Brian Weber~~	~~President~~	~~August 30, 2012~~
~~/s/ JAMES M. RUTLEDGE~~ ~~James M. Rutledge~~	~~Executive Vice President and Treasurer~~	~~August 30, 2012~~
~~/s/ ALAN S. MCKIM~~ ~~Alan S. McKim~~	~~Director~~	~~August 30, 2012~~