UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): April 3, 2013

CLEAN HARBORS, INC.

(Exact name of registrant as specified in its charter)

(781) 792-5000

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 9.01. Financial Statements and Exhibits.

(b) Pro Forma Financial Information

On December 28, 2012, Clean Harbors, Inc. (“Clean Harbors”) completed its previously announced acquisition of Safety-Kleen, Inc. (“Safety-Kleen”) through a merger of CH Merger Sub, Inc., a wholly-owned subsidiary of Clean Harbors, into Safety-Kleen, with Safety-Kleen surviving such merger as a wholly-owned subsidiary of Clean Harbors.

Clean Harbors’ Unaudited Pro Forma Condensed Combined Balance Sheet as at September 30, 2012, Unaudited Pro Forma Condensed Combined Statement of Income for the year ended December 31, 2011 and Unaudited Pro Forma Condensed Combined Statement of Income for the nine months ended September 30, 2012, each reflecting the acquisition of Safety-Kleen, were previously included in the Current Report on Form 8-K filed on January 4, 2013, as amended by the Amendment to the Current Report on Form 8-K/A filed on March 8, 2013.  Clean Harbors’ Consolidated Balance Sheet as at December 31, 2012, as included in Clean Harbors’ Annual Report on Form 10-K for the period then ended, filed on March 6, 2013, includes the assets and liabilities assumed from Safety-Kleen. The unaudited Pro Forma Condensed Combined Statement of Income for the year ended December 31, 2012, reflecting the acquisition of Safety-Kleen, is attached hereto as Exhibit 99.1.

(d) Exhibits

The information exhibits are filed herewith.

99.1 Unaudited Pro Forma Condensed Combined Statement of Income for the Year Ended December 31, 2012.

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SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the registrant has duly caused this current report on Form 8-K to be signed on its behalf by the undersigned hereunto duly authorized.

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Exhibit 99.1

CLEAN HARBORS, INC. AND SUBSIDIARIES

UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF INCOME

FOR THE YEAR ENDED DECEMBER 31, 2012

(in thousands)

See accompanying notes to unaudited pro forma condensed combined financial statements.

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 NOTES TO UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

1.                                      The Merger

On December 28, 2012, Clean Harbors acquired 100% of the outstanding common shares of Safety-Kleen, Inc. (“Safety-Kleen”) in accordance with an Agreement and Plan of Merger dated as of October 26, 2012 (the “Merger Agreement”). Safety-Kleen, a Delaware corporation headquartered in Richardson, Texas, is the largest re-refiner and recycler of used oil in North America and a leading provider of parts cleaning and environmental services.

Under the terms of the Merger Agreement, Clean Harbors agreed to pay to the Safety-Kleen’s shareholders and option holders cash consideration in an amount equal to $1.25 billion plus the amount of cash and cash equivalents held by Safety-Kleen on the closing date, less the amount of debt owed by Safety-Kleen on the closing date for borrowed money and capital lease obligations, plus or minus, as applicable, the amount by which Safety-Kleen’s working capital (excluding cash) on the closing date exceeded or was less than $50.0 million.

Safety-Kleen’s working capital (excluding cash) was estimated to be $57,259,000 as of December 28, 2012. Accordingly, the pro forma condensed combined financial statements included herein are based on an estimated purchase price of $1,257,259,000, including an estimated working capital adjustment of $7,259,000.  The purchase price is subject to adjustment upon finalization of Safety-Kleen’s working capital (excluding cash) on December 28, 2012.

The following summarizes the preliminary purchase price allocation at December 28, 2012 (in thousands):

Clean Harbors determined the preliminary purchase price allocations based on estimates of fair value of all tangible and intangible assets acquired and liabilities assumed.  Clean Harbors believes the preliminary allocations provide a reasonable basis for estimating the fair values of the assets acquired and liabilities assumed but is waiting for additional information necessary to finalize the fair values. Accordingly, the preliminary fair values presented above are subject to adjustment as more information becomes available. Clean Harbors expects to finalize the valuation and complete the purchase price allocation as soon as practicable, but no later than one year from the acquisition date. The final fair value amounts could differ materially from the preliminary estimates. Decreases or increases in the fair value of assets acquired or liabilities assumed from the preliminary estimates presented above would result in increases or decreases in the amount of goodwill resulting from the merger. In addition, if the value of the assets acquired is higher than the preliminary estimates, it may result in higher amortization and / or depreciation expense than the amounts presented in these pro forma statements.

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Clean Harbors has determined this to be a tax-free business combination from Clean Harbors’ standpoint.

2.                                      Financing

In connection with the merger, Clean Harbors sold (i) 6.9 million shares of its common stock in a Stock Offering (which was priced on November 27, 2012) at a public offering price of $56.00 per share on December 3, 2012 and (ii) $600.0 million of 5.125% senior unsecured notes due 2021in a Notes Offering on December 7, 2012. A summary of the net proceeds received from the Stock Offering and the Notes Offering was as follows (in thousands):

Clean Harbors also incurred approximately $5.2 million of commitment fees in connection with the merger financing. The completion of the merger and the Notes Offering resulted in approximately $10.6 million of deferred financing costs.

3.                                      Pro Forma Statement of Income Adjustments

The unaudited pro forma condensed combined statement of income does not include any non-recurring charges that will arise as a result of the merger described above.

(a)                                 Represents an adjustment of approximately $11.3 million to reduce revenues and cost of revenues for intercompany transactions between Clean Harbors and Safety-Kleen for the year ended December 31, 2012.

(b)                                 Represents the adjustment of $16.3 million to depreciation and amortization expense for the step-up in property, plant and equipment and identifiable intangibles to their preliminary estimated fair value at the acquisition date.  The step-up adjustments were calculated based on using the straight-line method over the estimated useful lives as follows:

The pro forma adjustment for property, plant and equipment consists of the following (in thousands):

(i)

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The pro forma adjustment for permits and other intangible assets consists of the following (in thousands):

(ii)

The step-up to the preliminary estimated fair value of Safety-Kleen’s identifiable intangible assets from the respective carrying values reported by Safety-Kleen as of December 28, 2012 was determined using a combination of the cost and market approach and the income approach. The estimated intangible assets are expected to be amortized on a straight-line basis over estimated useful lives, subject to the finalization of the purchase price allocation.

The pro forma depreciation and amortization adjustments are as follows (in thousands):

With other assumptions held constant, a 10% increase in the fair value of property, plant and equipment and intangible assets as calculated would increase annual pro forma depreciation and amortization expense by approximately $6.0 million for the year ended December 31, 2012. With other assumptions held constant, a 10% decrease in the estimated remaining useful lives of property, plant and equipment and amortizable intangible assets would increase pro forma depreciation and amortization by approximately $6.7 million for the year ended December 31, 2012. The increases in pro forma depreciation and amortization are as follows (in thousands):

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(c)                                  Represents adjustments to interest expense related to completion of the Notes Offering at an interest rate of 5.125% (including amortization of deferred financing costs) offset by the reversal of Safety-Kleen’s interest expense for outstanding debt.

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(d)                                 Represents the pro forma tax effect of the pro forma adjustments at an estimated statutory tax rate of 35.0% for the year ended December 31, 2012.  The pro forma income tax provision adjustment is as follows (in thousands):

(e)                                 For the year ended December 31, 2012, the dilutive effect of all then outstanding options, restricted stock and performance awards is included in the earnings per share calculation except for 65,000 Clean Harbors outstanding performance stock awards for which the performance criteria were not attained at that time.

(f)                                  Pro forma adjustment to reflect the newly issued 6.9 million common shares as outstanding for the year.

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