SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

Form 10-Q

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

for the Quarterly Period Ended
June 30, 2005

Commission File Number 0-16379

Clean Harbors, Inc.

(Exact name of registrant as specified in its charter)

(781) 849-1800 ext. 4454

(Registrant’s Telephone Number, Including Area Code)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding twelve months (or for such shorter period that the registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days.    Yes  ý    No  o

Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Act).    Yes  ý    No  o

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date.

CLEAN HARBORS, INC.

QUARTERLY REPORT ON FORM 10-Q

TABLE OF CONTENTS

PART I: FINANCIAL INFORMATION

CLEAN HARBORS, INC. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

ASSETS

Unaudited

(in thousands)

The accompanying notes are an integral part of these consolidated financial statements.

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CLEAN HARBORS, INC. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

LIABILITIES AND STOCKHOLDERS’ EQUITY

Unaudited

(dollars in thousands)

The accompanying notes are an integral part of these consolidated financial statements.

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CLEAN HARBORS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS

Unaudited

(in thousands except per share amounts)

The accompanying notes are an integral part of these consolidated financial statements.

3

CLEAN HARBORS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CASH FLOWS

Unaudited

(in thousands)

The accompanying notes are an integral part of these consolidated financial statements.

4

CLEAN HARBORS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

Unaudited

(in thousands)

The accompanying notes are an integral part of these consolidated financial statements.

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CLEAN HARBORS, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(1) Basis of Presentation

The accompanying consolidated interim financial statements include the accounts of Clean Harbors, Inc. and its wholly-owned subsidiaries (collectively, “Clean Harbors” or the “Company”) and have been prepared on a basis consistent with the annual financial statements and pursuant to the rules and regulations of the Securities and Exchange Commission and, in the opinion of management, include all adjustments which, except as described elsewhere herein, are of a normal recurring nature, necessary for a fair presentation of the financial position, results of operations, and cash flows for the periods presented. The results for interim periods are not necessarily indicative of results for the entire year. The financial statements presented herein should be read in connection with the financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2004.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires the Company’s management to make certain estimates and assumptions. These estimates and assumptions affect the reported amounts of assets and liabilities and disclosure of the contingent assets and liabilities at the date of the financial statements. These estimates and assumptions will also affect the reported amounts of certain revenues and expenses during the reporting period. Actual results could differ materially based on any changes in the estimates and assumptions that the Company uses in the preparation of its financial statements. Additionally, the estimates and assumptions used in determining landfill airspace amortization rates per cubic yard, capping, closure and post-closure liabilities as well as environmental remediation liabilities require significant engineering and accounting input. The Company reviews these estimates and assumptions on an ongoing basis. In many circumstances, the ultimate outcome of these estimates and assumptions may not be known for decades into the future. Actual results could differ materially from these estimates and assumptions due to changes in environmental-related regulations or future operational plans, and the inherent imprecision associated with estimating matters so far into the future.

Certain reclassifications have been made in the prior period’s Consolidated Financial Statements to conform to the presentation for the period ended June 30, 2005.

(2) Acquisition

As more fully described in the Form 10-K for the year ended December 31, 2004, the Company purchased from Safety-Kleen Services, Inc. (the “Seller”) and certain of the Seller’s domestic subsidiaries substantially all of the assets of the Chemical Services Division (the “CSD”) of Safety-Kleen Corp. (“Safety-Kleen”), effective September 7, 2002. The sale included the operating assets of certain of the Seller’s subsidiaries in the United States and the stock of five of the Seller’s subsidiaries in Canada.

In accordance with the Acquisition Agreement between the Seller and the Company dated February 22, 2002, as amended through September 6, 2002, the Company purchased the assets of the CSD for $26.6 million in net cash, and incurred direct costs related to the transaction of $9.7 million for a total purchase price of $36.3 million. In addition, the Company assumed with the transaction certain environmental liabilities then valued at $184.5 million.

(3) Significant Accounting Policies

(a) Revenue Recognition

The Company recognizes revenue when persuasive evidence of an arrangement exists, delivery has occurred or services have been rendered, the price is fixed or determinable, and collection is reasonably assured.

The Company provides a wide range of environmental services through two major segments: Technical Services and Site Services. Technical Services involve (i) services for collection, transportation and logistics management, (ii) services for the categorizing, packaging and removal of laboratory chemicals (Cleanpack®), and (iii) services related to the treatment and disposal of hazardous wastes. Site Services involve a wide range of services to maintain industrial facilities and process equipment, as well as clean up or contain actual or threatened releases of hazardous materials into the environment. Revenues for all services with the exception of services for the treatment and disposal of hazardous waste are recorded as services are rendered. Revenues for disposing of hazardous waste are recognized upon completion of wastewater treatment, landfill or incineration of the waste at a Company-owned site or when the waste is shipped to a third party for processing and disposal. Revenues from waste that is not yet completely processed and the related costs are deferred until services are completed. Revenue is recognized on contracts with retainage when services have been rendered and collectability  is reasonably assured.

(b) Operating Leases

The Company leases rolling stock, equipment, real estate and office equipment under operating leases. Certain real estate leases contain rent holidays and rent escalation clauses. Most of our real estate lease agreements include renewal periods at the Company’s option. The Company recognizes rent holiday periods and scheduled rent increases on a straight-line basis over the lease term beginning with the date the Company takes possession of the leased space.

(c) Closure and Post-Closure Liabilities

As further described in Note 4, “Significant Accounting Policies,” under item (m) “Closure and Post Closure Liabilities,” in the Form 10-K/A for the year ended December 31, 2004 as filed with the Securities and Exchange Commission on April 29, 2005, effective January 1, 2003, the Company adopted Statement of Accounting Standards “SFAS” No. 143, “Accounting for Asset Retirement Obligations.” The following disclosure enhances the previously made disclosures.

Inflation Rate and Credit-Adjusted Risk-Free Interest Rate

The Company uses an inflation rate published by the US Department of Labor Bureau of Labor Statistics that excludes the more volatile items of food and energy.

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For the asset retirement obligations incurred in 2005 and 2004, the Company estimated its credit-adjusted risk-free interest rate by adjusting the then current yield based on market prices of its $150 million Senior Secured Notes by the difference between the yield of a US treasury note of the same duration as the Senior Secured Notes and the yield on the 30 year U.S. Treasury Bond.

Financial Assurance

Prior to the adoption of SFAS No. 143, the Company accrued the cost of financial assurance relating to both landfill and non-landfill closure and to both landfill and non-landfill post-closure care, if required, under SFAS No. 5, “Accounting for Contingencies.” Under SFAS No. 143, financial assurance is no longer included as a component of closure or post-closure costs. SFAS No. 143 requires the cost of financial assurance to be expensed as incurred, and SFAS No. 143 requires the cost of financial assurance to be considered in the determination of the credit-adjusted risk-free interest rate.

Non-Landfill Closure and Post-Closure

Non-landfill closure costs include costs required to dismantle and decontaminate certain structures and other costs incurred during the closure process. Post-closure costs, if required, include associated maintenance and monitoring costs and financial assurance costs as required by the closure permit. Post-closure periods are performance-based and are not generally specified in terms of years in the closure permit, but may generally range from 10 to 30 years. The requirement to incur non-landfill closure and post-closure costs arise with the commencement of facility operations. Previous to the implementation of SFAS No. 143, the Company expensed non-landfill closure and post-costs when the decision was made to close a facility.

The Company records its non-landfill closure and post-closure liability by (i) estimating the current cost of closing a non-landfill facility and the post closure care of that facility, if required, based upon the closure plan that the Company is required to follow under its operating permit, or in the event the facility operates with a permit that does not contain a closure plan, based upon closure commitments made by the Company, (ii) using probability scenarios as to when in the future operations may cease, (iii) inflating the current cost of closing the non-landfill facility on a probability weighted basis using the inflation rate to the time of closing under each probability scenario, and (iv) discounting the future value of each closing scenario back to the present using the credit-adjusted risk-free interest rate.

(d) Stock Options

The Company applies Accounting Principles Board (“APB”) Opinion No. 25 and related Interpretations in accounting for its stock-based employee compensation plans. SFAS No. 123, “Accounting for Stock-Based Compensation” defines a fair value method of accounting for stock options and other equity instruments. Under the fair value method, compensation cost is measured at the grant date based on the fair value of the award and is recognized over the service period, which is usually the vesting period. The Company has elected to continue to apply the accounting provisions of APB Opinion No. 25 for stock options. Accordingly, no stock-based employee compensation cost is reflected in net income, as all options granted under those plans have an exercise price equal to the market value of the underlying common stock on the date of grant. Had compensation cost for the Company’s stock option grants been determined based on the fair value at the grant dates, as calculated in accordance with SFAS No. 123, the Company’s net income (loss) attributable to common shareholders and earnings (loss) per common share for the three- and six- month periods ended June 30, 2005 and 2004, would approximate the pro forma amounts as compared to the amounts reported (dollars in thousands except for per share amounts):

(e) New Accounting Pronouncements

In December 2004, the Financial Accounting Standards Board (“FASB”) issued Statement of Financial Accounting Standards (“SFAS”) No. 123 (revised 2004), “Share-Based Payment.” SFAS No. 123(R) replaces SFAS No. 123, “Accounting for Stock-Based Compensation,” and supercedes APB Opinion No. 25, “Accounting for Stock Issued to Employees.” SFAS No. 123(R) requires companies to report compensation cost relating to share-based payment transactions to be recognized in financial statements. That cost will be measured based upon the fair value of the equity or liability instruments issued. On March 29, 2005, the Securities and Exchange Commission (“SEC”) issued Staff Accounting Bulletin 107, “Share-Based Payment,” that expresses the views of the SEC staff regarding the application of SFAS No. 123(R). The Company is studying the Statement and the Bulletin. The Statement will increase compensation expense starting January 1, 2006.

           In March 2005, the FASB issued FASB Interpretation No. 47 (“FIN 47”), “Accounting for Conditional Asset Retirement Obligations.” FIN 47 clarifies that the term “conditional asset retirement obligation” as used in SFAS No. 143, “Accounting for Assets Retirements Obligations,” refers to a legal obligation to perform an asset retirement activity in which the timing and or method of settlement are conditional on a future event that may or may not be within the control of the entity. Furthermore, the uncertainty about the timing and or method of settlement of a conditional asset retirement obligations should be factored into the measurement of the liability when sufficient information exists. FIN 47 clarifies that an entity is required to recognize the liability for the fair value of a conditional asset when incurred if the liability’s fair value can be reasonably estimated. The Company is studying FIN 47 and has not determined what effect, if any, FIN 47 will have on the Company’s results of operations, financial condition or cash flows. The Company will implement FIN 47 effective January 1, 2006.

(4) Marketable Securities

As of December 31, 2004, the Company held $16.8 million in marketable securities. During the six-month period ended June 30, 2005, the Company liquidated these securities realizing no gain or loss.

(5) Properties Held For Sale

As part of its plan to integrate the activities of the CSD into its operation, the Company determined that certain acquired properties were no longer needed for its operations. The Company decided to sell these acquired properties; accordingly, the acquired surplus properties were transferred to properties held for sale. In the allocation of the purchase price of the CSD acquisition, the Company valued properties held for sale at the current appraised market value less estimated selling costs. In addition, subsequent to the completion of purchase accounting, the Company identified several additional properties that were no longer needed for its operations. These properties were transferred to properties held for sale at the lower of their net book value or current appraised market value less estimated selling costs. Properties held for sale include only those properties that the Company believes can be sold within the next twelve months based on current market conditions and the asking price. The Company cannot provide assurance that such sales will be completed within that period or that the proceeds from properties held for sale will equal their carrying value.

During the three-month period ended June 30, 2005 and the three-month period ended June 30, 2004, no properties were sold.

During the six-month period ended June 30, 2005, the Company sold one of the properties for $0.3 million, net of selling costs.  The sale resulted in a $5 thousand gain.  For the six-month period ended June 30, 2004, the Company sold one of the properties for $0.6 million, net of selling costs.  The sale resulted in a $0.2 million gain that is included in other income (expense).

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(6) Financing Arrangements

The following table is a summary of the Company’s financing arrangements:

As described in the Annual Report on Form 10-K for the year ended December 31, 2004, the Company has outstanding a $30.0 million revolving credit facility (the “Revolving Facility”) and $150.0 million of eight-year Senior Secured Notes (the “Senior Secured Notes”). In addition to such financings, the Company has established a synthetic letter of credit facility (the “Synthetic LC Facility”) whereby the Company may obtain up to $90.0 million of letters of credit as described below.

The principal terms of the Senior Secured Notes, the Revolving Facility, and the Synthetic LC Facility are as follows:

Senior Secured Notes. The Senior Secured Notes were issued under an Indenture dated June 30, 2004 (the “Indenture”). The Senior Secured Notes bear interest at 11.25% and mature on July 15, 2012. The Senior Secured Notes were issued at a $2.0 million discount that resulted in an effective yield of 11.5%. Interest is payable semiannually in cash on each January 15 and July 15.

The Indenture provides for certain covenants, the most restrictive of which requires the Company, within 120 days after the close of each twelve-month period ending on June 30 of each year (beginning June 30, 2005) to apply an amount equal to 50% of the period’s Excess Cash Flow (as defined below) to either prepay, repay, redeem or purchase its first-lien obligations under the Revolving Facility and Synthetic LC Facility or to make offers (“Excess Cash Flow Offers”) to repurchase all or part of the then outstanding Senior Secured Notes at an offering price equal to 104% of their principal amount plus accrued interest. “Excess Cash Flow” is defined in the Indenture as consolidated earnings before interest, taxes, depreciation and amortization (“ADJUSTED EBITDA”) less interest expense, all taxes paid or accrued in the period, capital expenditures made in cash during the period, and all cash spent on environmental monitoring, remediation or relating to environmental liabilities of the Company.

Excess Cash Flow for the twelve months ended June 30, 2005 was $29.5 million. The Company will within 120 days following June 30, 2005 offer to repurchase Senior Secured Notes in the amount of 50% of the Excess Cash Flow generated during the twelve-month period ending June 30, 2005. However, at June 30, 2005, the Company had no outstanding first-lien obligations under its Revolving Facility or Synthetic LC Facility and, during the six-month period ended June 30, 2005, the market price of the Senior Secured Notes was consistently in excess of the 104% of principal amount at which the Company is required and permitted by the Indenture and the Credit Agreement to make Excess Cash Flow Offers for outstanding Senior Secured Notes. It therefore now appears unlikely that any holders of Senior Secured Notes will accept an Excess Cash Flow Offer made in accordance with the Indenture and the Credit Agreement unless the trading price of the Senior Secured Notes declines prior to the time in 2005 at which the Company will make such an offer. To the extent the Note holders do not accept an Excess Cash Flow Offer based on the Excess Cash Flow earned through June 30, 2005, such Excess Cash Flow will not be included in the amount of Excess Cash Flow earned in subsequent periods. However, the Indenture’s requirement to make Excess Cash Flow Offers in respect of Excess Cash Flow earned in subsequent twelve-month periods will remain in effect.

Revolving Facility. Both the Revolving Facility and the Synthetic LC Facility were established under a Loan and Security Agreement dated June 30, 2004 (the “Credit Agreement”) among the Company, Fleet Capital Corporation as agent for the Revolving Lenders thereunder, Credit Suisse First Boston as agent for the letter of credit facility lenders (the “LC Facility Lenders”) thereunder, and certain other parties. The Revolving Facility allows the Company to borrow up to $30.0 million in cash, based upon a formula of

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eligible accounts receivable. This total is separated into two lines of credit, namely a line for the Company and its U.S. subsidiaries equal to $24.7 million and a line for the Company’s Canadian subsidiaries of $5.3 million. The Revolving Facility also allows the Company to have issued up to $10.0 million of letters of credit, with the outstanding amount of such letters of credit reducing the maximum amount of borrowings permitted under the Revolving Facility. At June 30, 2005, the Company had no borrowings and $1.2 million of letters of credit outstanding under the Revolving Facility, and the Company had approximately $28.8 million available to borrow. Amounts outstanding under the Revolving Facility bear interest at an annual rate of either the U.S. or Canadian prime rate or the Eurodollar rate (depending on the currency of the underlying loan) plus 1.50%. The Credit Agreement requires the Company to pay an unused line fee of 0.125% per annum on the unused portion of the Revolving Facility. The Revolving Facility matures on June 30, 2009.

Under the Credit Agreement, the Company is required to maintain a maximum Leverage Ratio (as defined below) of no more than 2.50 to 1.0 for the four-quarter periods ended June 30, 2005 through March 31, 2006. The maximum leverage ratio is then reduced in approximately equal increments to no more than 2.30 to 1.0 for the four-quarter period ending December 31, 2008, and to no more than 2.25 to 1.0 for each succeeding quarter. The Leverage Ratio is defined as the ratio of the consolidated indebtedness of the Company to its consolidated ADJUSTED EBITDA achieved for the latest four-quarter period. For the four-quarter period ended June 30, 2005, the Leverage Ratio was 1.55 to 1.0, which was within covenant.

The Company is also required under the Credit Agreement to maintain a minimum Interest Coverage Ratio (as defined below) of not less than 2.70 to 1.0 for the four-quarter periods ended June 30, 2005 through December 31, 2005.  The minimum interest coverage ratio then decreases in approximately equal increments, to not less than 2.85 to 1.0 for the four-quarter period ending December 31, 2007, and not less than 3.00 to 1.0 for each succeeding four-quarter period. The Interest Coverage Ratio is defined as the ratio of the Company’s consolidated ADJUSTED EBITDA to its consolidated interest expense. For the four-quarter period ended June 30, 2005, the Interest Coverage Ratio was 3.78 to 1.0, which was within covenant.

The Company is also under the Credit Agreement required to maintain a fixed charge coverage ratio of not less than 1.0 to 1.0 for each four-quarter period. For the period ended June 30, 2005, the Company’s fixed charge coverage ratio was 2.12 to 1.0, which was within covenant.

Synthetic LC Facility. The Synthetic LC Facility provides that Credit Suisse First Boston (the “LC Facility Issuing Bank”) will issue up to $90.0 million of letters of credit at the Company’s request. The LC Facility requires that the LC Facility Lenders maintain a cash account (the “Credit-Linked Account”) to collateralize the Company’s outstanding letters of credit. Should any such letter of credit be drawn in the future and the Company fails to satisfy its reimbursement obligation, the LC Facility Issuing Bank would be entitled to draw upon the appropriate portion of the $90.0 million in cash which the LC Facility Lenders under the Credit Agreement have deposited into the Credit-Linked Account. Acting through the LC Facility Agent, the LC Facility Lenders would then have the right to exercise their rights as first-priority lien holders (second-priority as to receivables) on substantially all of the assets of the Company and its domestic subsidiaries. The Company has no right, title or interest in the Credit-Linked Account established under the Credit Agreement for purposes of the Synthetic LC Facility. The Company is required to pay (i) a quarterly participation fee at the annual rate of 5.35% on the average daily balance in the Credit-Linked Account and (ii) a quarterly fronting fee at the annual rate of 0.30% of the average daily aggregate amount of letters of credit outstanding under the Synthetic LC Facility. At June 30, 2005, letters of credit outstanding under the Synthetic LC facility were $89.2 million. The term of the Synthetic LC Facility will expire on June 30, 2009.

Earnings before Interest, Taxes, Depreciation, Amortization, Non-Recurring Severance Charges, Other Non-recurring Refinancing-Related Expenses, Change in Value of Embedded Derivative, and Gain (Loss) on Sale of Fixed Assets (“ADJUSTED EBITDA”)

The Company defines ADJUSTED EBITDA (a measure not defined under generally accepted accounting principles) as it is defined under the Loan and Security Agreement dated June 30, 2004. This definition is net income (loss) plus accretion of environmental liabilities, depreciation and amortization, net interest expense, provision for (benefit from) income taxes, non-recurring severance charges, other non-recurring refinancing-related expenses, change in value of embedded derivative, and gain (loss) on sale of fixed assets.

The Company’s management considers ADJUSTED EBITDA to be a measurement of performance, which provides useful information to both management and investors. ADJUSTED EBITDA should not be considered an alternative to net income or loss or other measurements under accounting principles generally accepted in the United States. Because ADJUSTED EBITDA is not calculated identically by all companies, our measurements of ADJUSTED EBITDA may not be comparable to similarly titled measures reported by other companies.

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The following is a reconciliation of net income to ADJUSTED EBITDA for the six months ended June 30, 2005:

The following reconciles ADJUSTED EBITDA to cash provided for operations for the six months ended June 30, 2005:

7) Legal Proceedings

General Environmental Matters

The Company’s waste management services are continuously regulated by federal, state, provincial and local laws enacted to regulate discharge of materials into the environment, remediation of contaminated soil and groundwater or otherwise protect the environment. This ongoing regulation results in the Company frequently becoming a party to judicial or administrative proceedings involving all levels of governmental authorities and other interested parties. The issues involved in such proceedings generally relate to applications for permits and licenses by the Company and conformity with legal requirements, alleged violations of existing permits and licenses or requirements to clean up contaminated sites. At June 30, 2005, the Company was involved in various proceedings, the principal of which are described below, relating primarily to activities at or shipments to and/or from the Company’s waste treatment, storage and disposal facilities.

Legal Proceedings Related to Acquisition of CSD Assets

Effective September 7, 2002 (the “Closing Date”), the Company purchased from Safety-Kleen Services, Inc. and certain of its domestic subsidiaries (collectively, the “Sellers”) substantially all of the assets of the Chemical Services Division (the “CSD”) of Safety-Kleen Corp. (“Safety-Kleen”). The Company purchased the CSD assets pursuant to a sale order (the “Sale Order”) issued by the Bankruptcy Court for the District of Delaware (the “Bankruptcy Court”) which had jurisdiction over the Chapter 11 proceedings involving the Sellers, and the Company therefore took title to the CSD assets without assumption of any liability (including pending or threatened litigation) of the Sellers except as expressly provided in the Sale Order. However, under the Sale Order (which incorporated by reference certain provisions of the Acquisition Agreement between the Company and Safety-Kleen Services, Inc.), the Company became subject to certain legal proceedings involving the CSD assets for three reasons as described below. As of June 30, 2005, the Company had reserves of $34.1 million (substantially all of which the Company had established as part of the purchase price for the CSD assets) relating to the Company’s estimated potential liabilities in connection with such legal proceedings, which were then pending. The Company also estimates that it is “reasonably possible” as that term is defined in SFAS No.5 (more than remote but less than likely), that the amount of such total liabilities could be up to $3.0 million greater than such $ 34.1 million.  Because all of the Company’s reasonably possible additional losses relating to legal liabilities relate to remedial liabilities, the reasonably possible additional losses for legal liabilities are reflected in the tables of reasonably possible additional losses in Note 9, “Remedial

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Liabilities.” The Company periodically adjusts the aggregate amount of such reserves when such potential liabilities are paid or otherwise discharged or additional relevant information becomes available to the Company.

The first reason for the Company becoming subject to certain legal proceedings in connection with the acquisition of the CSD assets is that, as part of the CSD assets, the Company acquired all of the outstanding capital stock of certain Canadian subsidiaries (the “CSD Canadian Subsidiaries”) formerly owned by the Sellers (which subsidiaries were not part of the Sellers’ bankruptcy proceedings), and the Company therefore became subject to the legal proceedings (which include the Ville Mercier Legal Proceedings described below) in which the Canadian Subsidiaries were then involved. The second reason is that, on the Closing Date for the CSD assets, there were ongoing legal proceedings (which include the FUSRAP Legal Proceedings described below), which directly involved certain of the CSD assets of which the Company became the owner and operator. While the Company did not agree to be responsible for damages or other liabilities of the Sellers relating to such proceedings, these proceedings might nevertheless affect the future operation of those CSD assets. The third reason is that, as part of the purchase price for the CSD assets, the Company agreed with the Sellers that the Company would indemnify the Sellers against certain current and future liabilities of the Sellers under applicable federal and state environmental laws including, in particular, the Sellers’ share of certain cleanup costs payable to governmental entities under the Comprehensive Environmental Response, Compensation and Liability Act (“Superfund Act”) or analogous state Superfund laws. As described below, the Company and the Sellers are not in complete agreement at this time as to the scope of the Company’s indemnity obligations under the Sale Order and the Acquisition Agreement with respect to certain Superfund liabilities of the Sellers.

The principal legal proceedings related to the Company’s acquisition of the CSD assets are as follows. While, as described below, the Company has established reserves for certain of these matters, there can be no guarantee that any ultimate liability the Company incurs for any of these matters will not exceed (or be less than) the amount of the current reserves or that the Company will not incur other material expenditures.

Ville Mercier Legal Proceedings.  One of the CSD Canadian Subsidiaries (the “Mercier Subsidiary”) owns and operates a hazardous waste incinerator in Ville Mercier, Quebec (the “Mercier Facility”). A property owned by the Mercier Subsidiary adjacent to the current Mercier Facility is now contaminated as a result of actions dating back to 1968, when the Quebec government issued to the unrelated company which then owned the Mercier Facility two permits to dump organic liquids into lagoons on the property. By 1972, groundwater contamination had been identified, and the Quebec government provided an alternate water supply to the municipality of Ville Mercier.

In 1999, Ville Mercier and three neighboring municipalities filed separate legal proceedings against the Mercier Subsidiary and certain related companies together with certain former officers and directors, as well as against the Government of Quebec. The lawsuits assert that the defendants are jointly and severally responsible for the contamination of groundwater in the region, which the plaintiffs claim was caused by contamination from the former Ville Mercier lagoons and which they claim caused each municipality to incur additional costs to supply drinking water for their citizens since the 1970’s and early 1980’s. The four municipalities claim a total of $1.6 million (CDN) as damages for additional costs to obtain drinking water supplies and seek an injunctive order to obligate the defendants to remediate the groundwater in the region. The Quebec Government also sued the Mercier Subsidiary to recover approximately $17.4 million (CDN) of alleged past costs for constructing and operating a treatment system and providing alternative drinking water supplies. The Mercier Subsidiary continues to assert that it has no responsibility for the groundwater contamination in the region.

Because the continuation of such proceedings by the Mercier Subsidiary, which the Company now owns, would require the Company to incur legal and other costs and the risks inherent in any such litigation, the Company, as part of its integration plan for the CSD assets, decided to vigorously review options which will allow the Company to establish harmonious relations with the local communities, resolve the adversarial situation with the Provincial government and spare continued legal costs. Based upon the Company’s review of likely settlement possibilities, the Company now anticipates that as part of any such settlement it will likely agree to assume at least partial responsibility for remediation of certain environmental contamination and certain prior costs. At June 30, 2005, the Company had accrued $10.6 million for remedial liabilities and associated legal costs relating to the Ville Mercier Legal Proceedings.

FUSRAP Legal Proceedings.  As part of the CSD assets, the Company acquired a hazardous waste landfill in Buttonwillow, California (the “Buttonwillow Landfill”). During 1998 and 1999, the Seller’s subsidiary which then owned the Buttonwillow Landfill (the “Buttonwillow Seller”) accepted and disposed in the Buttonwillow Landfill certain construction debris (the “FUSRAP Wastes”) that originated at a site in New York that was part of the federal Formerly Utilized Sites Remedial Action Program (“FUSRAP”). FUSRAP was created in the mid-1970s in an attempt to manage various sites around the country contaminated with residual radioactivity from activities conducted by the Atomic Energy Commission and the United States military during World War II. The FUSRAP Wastes are primarily construction and demolition debris exhibiting low-activity residual radioactivity that were shipped to the Buttonwillow Landfill by the U.S. Army Corps of Engineers.

The California Department of Health Services (“DHS”) claimed in a letter to the Buttonwillow Seller delivered in 1999 that the Buttonwillow Seller did not lawfully accept the FUSRAP Wastes under applicable California law and regulations. Both DHS and the California Department of Toxic Substances Control (“DTSC”) filed claims in the Sellers’ bankruptcy proceedings preserving the right

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of those agencies to claim penalties for damages against the Buttonwillow Seller and possibly seeking to compel removal of the FUSRAP Wastes from the Buttonwillow Landfill. However, aside from the letter to the Buttonwillow Seller and the filing of the proofs of claim in the Sellers’ bankruptcy proceedings, the California agencies have not commenced any enforcement proceedings relating to the Buttonwillow Landfill. Both the Company and the Sellers believe that the FUSRAP Wastes were properly, safely and lawfully disposed of at the Buttonwillow Landfill under all applicable laws and regulations, and the Company would vigorously resist any efforts to require that such wastes be removed if either of the California agencies should in the future initiate any enforcement action for this purpose. The Company now estimates that the cost of removing the FUSRAP Wastes from the Buttonwillow Landfill would be approximately $6.9 million. However, the Company has not accrued any costs of removing the FUSRAP Wastes because the Company believes that, in the event the California agencies were in the future to initiate any enforcement action, only a remote possibility exists that a final order would be issued requiring the Company to remove such wastes.

Indemnification of Certain CSD Superfund Liabilities.  The Company’s agreement with the Sellers under the Acquisition Agreement and the Sale Order to indemnify the Sellers against certain cleanup costs payable to governmental entities under federal and state Superfund laws now relate primarily to (i) two properties included in the CSD assets which are either now subject or proposed to become subject to Superfund proceedings, (ii) certain potential liabilities which the Sellers might incur in the future in connection with an incinerator formerly operated by Marine Shale Processors, Inc. to which the Sellers shipped hazardous wastes, and (iii) 35 active Superfund sites owned by third parties where the Sellers have been designated as Potentially Responsible Parties (“PRPs”). As described below, there are also four other Superfund sites owned by third parties where the Sellers have been named as PRPs or potential PRPs and for which the Sellers have sent demands for indemnity to the Company since September 2004. In the case of the two properties referenced above which were included in the CSD assets, the Company is potentially directly liable for cleanup costs under applicable environmental laws because of the Company’s ownership and operation of such properties since the Closing Date. In the case of Marine Shale Processors and the 35 other third-party sites referenced above, the Company does not have direct liability for cleanup costs but may have an obligation to indemnify the Sellers, to the extent provided in the Acquisition Agreement and the Sale Order, against the Sellers’ share of such cleanup costs which are payable to governmental entities.

Federal and state Superfund laws generally impose strict, and in certain circumstances, joint and several liability for the costs of cleaning up Superfund sites not only upon the owners and operators of such sites, but also upon persons or entities which in the past have either generated or shipped hazardous wastes which are present on such sites. The Superfund laws also provide for liability for damages to natural resources caused by hazardous substances at such sites. Accordingly, the Superfund laws encourage PRPs to agree to share in specified percentages of the aggregate cleanup costs for Superfund sites by entering into consent decrees, settlement agreements or similar arrangements. Non-settling PRPs may be liable for any shortfalls in government cost recovery and may be liable to other PRPs for equitable contribution. Under the Superfund laws, a settling PRP’s financial liability could increase if the other settling PRPs were to become insolvent or if additional or more severe contamination were discovered at the relevant site. In estimating the amount of those Sellers’ liabilities at those Superfund sites where one or more of the Sellers has been designated as a PRP and as to which the Company believes that it has potential liability under the Acquisition Agreement and the Sale Order, the Company therefore reviewed any existing consent decrees, settlement agreements or similar arrangements with respect to those sites, the Sellers’ negotiated volumetric share of liability (where applicable), the Company’s prior knowledge of the relevant sites, and the Company’s general experience in dealing with the cleanup of Superfund sites.

Properties Included in CSD Assets.  The CSD assets acquired by the Company include an active service center located at 2549 North New York Street in Wichita, Kansas (the “Wichita Property”). The Wichita Property is one of several properties located within the boundaries of a 1,400-acre state-designated Superfund site in an old industrial section of Wichita known as the North Industrial Corridor Site. Along with numerous other PRPs, the Sellers executed a consent decree relating to such site with the EPA, and the Company is continuing its ongoing remediation program for the Wichita Property in accordance with that consent decree. Also included within the CSD assets acquired by the Company are rights under an indemnification agreement between the Sellers and a prior owner of the Wichita Property, which the Company anticipates, but cannot guarantee will be available to reimburse certain such cleanup costs.

The CSD assets also include a former hazardous waste incinerator and landfill in Baton Rouge, Louisiana (“BR Facility”) currently undergoing remediation pursuant to an order issued by the Louisiana Department of Environmental Quality. In December 2003, the Company received an information request from the federal EPA pursuant to the Superfund Act concerning the Devil’s Swamp Lake Site (“Devil’s Swamp”) in East Baton Rouge Parish, Louisiana. On March 8, 2004, the EPA proposed to list Devil’s Swamp on the National Priorities List for further investigations and possible remediation. Devil’s Swamp includes a lake located downstream of an outfall ditch where wastewaters and stormwaters have been discharged from the BR Facility, as well as extensive swamplands adjacent to it. Contaminants of concern cited by the EPA as a basis for listing the site include substances of the kind found in wastewaters discharged from the BR Facility in past operations. While the Company’s ongoing corrective actions at the BR Facility may be sufficient to address the EPA’s concerns, there can be no assurance that additional action will not be required and that the Company will not incur material costs. The Company cannot now estimate its potential liability for Devil’s Swamp; accordingly, the Company has accrued no liability for remediation of Devil’s Swamp beyond what was already accrued pertaining to the ongoing corrective actions and amounts sufficient to cover certain projected legal fees and related expenses.

Marine Shale Processors.  Beginning in the mid-1980s and continuing until July 1996, Marine Shale Processors, Inc., located in

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Amelia, Louisiana (“Marine Shale”), operated a kiln, which incinerated waste producing a vitrified aggregate as a by-product. Marine Shale contended that its operation recycled waste into a useful product, i.e., vitrified aggregate, and therefore was exempt from regulation under the Resource Conservation Recovery Act (“RCRA”) and permitting requirements as a hazardous waste incinerator under applicable federal and state environmental laws. The EPA contended that Marine Shale was a “sham-recycler” subject to the regulation and permitting requirements as a hazardous waste incinerator under RCRA, that its vitrified aggregate by-product was a hazardous waste, and that Marine Shale’s continued operation without required permits was illegal. Litigation between the EPA and Marine Shale began in 1990 and continued until July 1996 when the U.S. Fifth Circuit Court of Appeals ordered Marine Shale to shutdown its operations. During the course of its operation, Marine Shale produced thousands of tons of aggregate, some of which was sold as fill material at various locations in the vicinity of Amelia, Louisiana, but most of which was stockpiled on the premises of the Marine Shale facility. Almost all of this aggregate has since been moved to a nearby site owned by an affiliate of Marine Shale, known as Recycling Park, Inc. In accordance with a court order authorizing the movement of this material to this off-site location, all of the materials located at Recycling Park, Inc. comply with the land disposal restrictions of RCRA. Approximately 7,000 tons of aggregate remain on the Marine Shale site. Moreover, as a result of past operations, soil and groundwater contamination may exist on the Marine Shale facility and the Recycling Park, Inc. site.

Although the Sellers never held an equity interest in Marine Shale, the Sellers were among the largest customers of Marine Shale in terms of overall incineration revenue. Based on a plan to settle obligations that was established at the time of the acquisition, the Company obtained more complete information as to the potential status of the Marine Shale facility and the Recycling Park, Inc. site as a Superfund site or sites, the potential costs associated with possible removal and disposal of some or all of the vitrified aggregate and closure and remediation of the Marine Shale facility and the Recycling Park, Inc. site, and the respective shares of other identified potential PRPs on a volumetric basis. Accordingly, the Company determined in the third quarter of 2003 that the remedial liabilities and associated legal costs were then probable and estimable and recorded liabilities for the Company’s estimate of the Sellers’ proportionate share of environmental cleanup costs potentially payable to governmental entities under federal and/or state Superfund laws. At June 30, 2005, the Company had accrued $13.4 million of reserves relating to potential cleanup costs for the Marine Shale facility and the Recycling Park, Inc. site.

On December 24, 2003, the Sellers’ plan of reorganization became effective under chapter 11 of the Bankruptcy Code. If the EPA or the Louisiana Department of Environmental Quality (“LDEQ”) were in the future to designate the Marine Shale facility and/or the Recycling Park, Inc. site as a Superfund site or sites, the Sellers might assert that they are not responsible for potential cleanup costs associated with such site or sites, and the Company might assert that under the Sale Order the Company is not obligated to pay or reimburse cleanup and related costs associated with such site or sites. The Company cannot now provide assurances with respect to any such matters which, in the event the EPA or the LDEQ were in the future to designate the Marine Shale facility and/or the Recycling Park, Inc. site as a Superfund site or sites, would need to be resolved by future events, negotiations and, if required, legal proceedings.

Third Party Superfund Sites.  Prior to the Closing Date, the Sellers had generated or shipped hazardous wastes, which are present on an aggregate of 35 sites owned by third parties, which have been designated as federal or state Superfund sites and at which the Sellers, along with other parties, had been designated as PRPs. Under the Acquisition Agreement and the Sale Order, the Company agreed with the Sellers that the Company would indemnify the Sellers against the Sellers’ share of the cleanup costs payable to governmental entities in connection with those 35 sites, which were listed in Exhibit A to the Sale Order (the “Listed Third Party Sites”). At 29 of the Listed Third Party Sites, the Sellers had addressed, prior to the Company’s acquisition of the CSD assets in September 2002, the Sellers’ cleanup obligations to the federal and state governments and to other PRPs by entering into consent decrees or other settlement agreements or by participating in ongoing settlement discussions or site studies and, in accordance therewith, the PRP group is generally performing or has agreed to perform the site remediation program with government oversight. With respect to one of those 29 Listed Third Party Sites, certain developments have occurred since the Company’s purchase of the CSD assets as described in the following two paragraphs. Of the six remaining Listed Third Party Sites, the Company on behalf of the Sellers is contesting with the governmental entities and PRP groups involved liability at two sites, has settled the Sellers’ liability at one site, confirmed that the Sellers were ultimately not named as PRPs at one site, and plans to fund participation by the Sellers as settling PRPs at three sites. With respect to the 35 Listed Third Party Sites, the Company had reserves of $17.9 million at June 30, 2005.

With respect to one of those 35 sites (the “Helen Kramer Landfill Site”), the Sellers had entered (prior to the Sellers commencing their bankruptcy proceeding in June 2000) into settlement agreements with certain members of the PRP group which agreed to perform the cleanup of that site in accordance with a consent decree with governmental entities, in return for which the Sellers received a conditional release from such governmental entities. Following the Sellers’ commencement of their bankruptcy proceeding, the Sellers failed to satisfy their payment obligations to those PRPs under those settlement agreements.

In November 2003, certain of those PRPs made a demand directly on the Company for the Sellers’ share of the cleanup costs incurred by the PRPs with respect to the Helen Kramer Landfill Site. However, at a hearing in the Bankruptcy Court on January 6, 2004 on a motion by those PRPs seeking an order that the Company was liable to such PRPs under the terms of the Sale Order, the Bankruptcy Court declined to hear the motion on the ground that those PRPs (which are not governmental entities) have no right to seek direct payment from the Company for any portion of the cleanup costs which they have incurred in connection with that site. The

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Company’s legal position is that when the Sellers’ plan of reorganization became effective in December 2003, the Sellers likely were discharged from their obligations to those PRPs for that site.  The Sellers have never made an indemnity request upon the Company for any obligations relating to that site. The PRPs have indicated their intention to pursue additional recourse against the Company, but the Company filed in February 2005 a complaint with the Bankruptcy Court seeking sanctions against the PRPs for contempt of the injunction in the Sale Order against those PRPs’ efforts to proceed directly against the Company, and that matter is still pending. On April 20, 2005, the Company’s general counsel advised the Company that its exposure to liability for the Sellers’ obligations with respect to the Helen Kramer Landfill Site are no longer “probable,” and the Company therefore reversed a $1.9 million reserve which the Company had established with respect to those potential liabilities in connection with the Company’s acquisition of the CSD assets. The reversal of the $1.9 million reserve was recorded to selling, general and administrative expenses.

By letters to the Company dated September 22 and 28, 2004, and January 22 and 28, 2005, the Sellers identified, in addition to the 35 Listed Third Party Sites, four additional sites owned by third parties which the EPA or a state environmental agency has designated as a Superfund site or potential Superfund site and at which one or more of the Sellers have been named as a PRP or potential PRP. In those letters, the Sellers asserted that the Company has an obligation to indemnify the Sellers for their share of the potential cleanup costs associated with such four additional sites. The Company has responded to such letters from the Sellers by stating that, under the Sale Order, the Company has no obligation to reimburse the Sellers for any cleanup and related costs (if any), which the Sellers may incur in connection with such four additional sites. The Company intends to assist the Sellers in providing information now in the Company’s possession with respect to such four additional sites and to participate in negotiations with the government agencies and PRP groups involved. In addition, at one of those four additional sites, the Company may have some liability independently of the Sellers’ involvement with that site, and the Company may also have certain defense and indemnity rights under contractual agreements for prior acquisitions relating to that site. Accordingly, the Company is now investigating that site further. However, the Company now believes that it has no liabilities with respect to the potential cleanup of those four additional sites that are both probable and estimable at this time, and the Company has therefore not established any reserves for any potential liabilities of the Sellers in connection therewith. It is expressly the Company’s legal position that it is not liable at any of the four sites for any and/or all of the Sellers’ liabilities. In any event, at one site the potential liability of the Seller(s) is de minimis and a settlement has already been offered to the Seller(s) to that effect, and at one site it is believed that the Seller(s) shipped no wastes or substances into the site and therefore the Seller(s) have no liability. For the other two sites, the Company cannot estimate the amount of the Sellers’ liabilities, if any, at this time, and that irrespective of whatever liability the seller’s may or may not have, the Company reaffirms its position that it does not have any liability for any of the four sites including these two particular sites.

Inactive Third Party Superfund Sites.  In addition to the Superfund sites owned by third parties described in the preceding paragraphs, the Sellers have also been identified as PRPs at several other federal or state Superfund sites owned by third parties that the Company believes are now inactive with respect to the Sellers. The inactive sites generally involve the shipment by the Sellers of a de minimis amount of wastes to such sites and prior consent decrees, settlement agreements or similar arrangements providing for minimal payment obligations by the Sellers. De minimis agreements generally are intended to settle all claims for small PRPs and such agreements have limited “re-opener” provisions. At certain other inactive sites, the Sellers have disclaimed any liability by advising the governmental entities involved that the Sellers had not shipped any wastes to those sites. The Company has not established reserves for any of the inactive sites because the Company believes that the Sellers’ cleanup liabilities with respect to those sites have already been resolved and that, under the Sale Order, the Company would not be responsible for such liabilities in any event.

Other Legal Proceedings Related to CSD Assets

In addition to the legal proceedings related to the acquisition of the CSD assets described above, subsequent to the acquisition in September 2002 various plaintiffs which are represented by the same law firm have filed three lawsuits based in part upon allegations relating to ownership and operation of a deep injection well facility near Plaquemine, Louisiana which Clean Harbors Plaquemine, LLC (“CH Plaquemine”), one of the Company’s subsidiaries, acquired as part of the CSD assets. The first such lawsuit was filed in December 2003 in the 18th Judicial District Court in Iberville Parish, Louisiana, against CH Plaquemine under the citizen suit provisions of the Louisiana Environmental Quality Act. The lawsuit alleges that the facility is in violation of state law by disposing of hazardous waste into an underground injection well that the plaintiffs allege is located within the banks or boundaries of a body of surface water within the jurisdiction of the State of Louisiana. The lawsuit also focuses on a “new area of concern” at the facility, which the plaintiffs allege is a source of contamination, which will require environmental remediation and/or restoration. The lawsuit also alleges that CH Plaquemine’s former facility manager made false representations and failed to disclose material information to the regulators about the facility after CH Plaquemine acquired it in September 2002. The plaintiffs seek an order declaring the facility to be located within the banks or boundaries of a body of surface water under state law, payment of civil penalties of $27,500 per violation per day from and after November 17, 2003, and an additional penalty of $1.0 million for damages to the environment, plus interest. The plaintiffs also seek an order requiring the facility to remove all waste disposed of since September of 2002, and in general, to conduct an investigation into and remediate the alleged contamination at the facility, as well as damages for alleged personal injuries and property damage, natural resources damages, costs of litigation, and attorney’s fees. On January 14, 2005, the state district court judge granted the plaintiffs’ petition for a preliminary (or temporary) injunction restraining the subsidiary from disposing of hazardous waste in the injection well. On January 18, 2005 (the next day the court was again open for business) CH Plaquemine filed a motion seeking to stay the preliminary injunction, which the same judge granted. The legal effect of the stay order was to allow the facility to continue normal business operations and to continue injecting hazardous waste, pending an appeal. In accordance with the stay order that was granted in favor of the subsidiary, CH Plaquemine has appealed the court’s initial ruling granting the preliminary (or temporary) injunction to the Louisiana First Circuit Court of Appeal in Baton Rouge, and that appeal is presently pending.

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In February 2005 this same group of plaintiffs sent notice to the Louisiana Department of Environmental Quality that they intended to file a second citizen suit. In April 2005, the second citizen suit petition was filed naming Clean Harbors, Inc. (“CHI”), Clean Harbors Environmental Services, Inc. (“CHESI”), and an employee of CHESI as defendants. The second citizen suit alleges that CHI, CHESI and the CHESI employee are liable for conduct based upon claims that are substantially similar in nature to those filed against CH Plaquemine in the original citizen suit and also alleges that CHI and CHESI are liable for certain aspects of the operations of CH Plaquemine under the lawsuit’s so-called “Single Business Entity Doctrine.” This second lawsuit seeks civil penalties of $10,000 per day per violation from an unspecified date. Both CHI and CHESI have filed motions to dismiss the suit against them.

In June 2005, the same plaintiff’s lawyers who filed the two lawsuits described immediately above filed a petition to add CHI, CHESI, CH Plaquemine and the two (one former, one current) employee defendants, to a lawsuit commenced in 1996 against the former owner of the site.  While the allegations of that suit are slightly different from the two lawsuits described above, CHI and CHESI are again named in the petition as defendants based largely on the so-called “Single Business Entity Doctrine.”  This third lawsuit also names as defendants certain former owners and operators of the facility and the insurance company that currently provides environmental impairment liability insurance coverage for the facility, and seeks unspecified damages and attorney’s fees.

The Company believes that all three of these lawsuits are without merit, and is vigorously defending against the claims made. The Company further believes that, since its acquisition by CH Plaquemine, the Plaquemine facility has been and now is in full compliance with its operating permits and all applicable state laws, and that any alleged contamination in the “new area of concern” complained of by the plaintiffs was and is already being addressed under the corrective action provisions of its RCRA operating permit. In addition, the Company believes that many of the plaintiffs’ claims relate to actions or omissions allegedly taken or caused prior to September 2002 by third parties that formerly owned and/or operated, or generated or shipped waste to, the Plaquemine facility for which the Company has no legal responsibility under the Sale Order. Prior to June 30, 2005, the Company had incurred legal expenses in connection with defending against these three lawsuits that satisfied the $1.0 million deductible on the Company’s environmental impairment liability insurance applicable to the Plaquemine facility. Because the Company believes the claims against CH Plaquemine, CHI and CHESI in the three lawsuits are without merit and that the Company has adequate insurance to cover any future liabilities associated with such lawsuits, the Company does not now maintain any reserves associated with the three Plaquemine lawsuits.

Legal Proceedings Not Related to CSD Assets

In addition to the legal proceedings in which the Company became involved as a result of its acquisition of the CSD assets, the Company is also involved in certain legal proceedings, which have arisen for other reasons. The principal such legal proceedings include certain Superfund proceedings relating to sites owned by third parties where the Company (or a predecessor) has been named a PRP, certain regulatory proceedings, and litigation involving the former holders of the Company’s subordinated notes.

Superfund Sites Not Related to CSD Acquisition

The Company has been named as a PRP at 28 sites that are not related to the CSD acquisition. Fourteen of these sites involve two subsidiaries, which the Company acquired from ChemWaste, a former subsidiary of Waste Management, Inc. As part of that acquisition, ChemWaste agreed to indemnify the Company with respect to any liability of those two subsidiaries for waste disposed of before the Company acquired them. Accordingly, Waste Management is paying all costs of defending those two Company subsidiaries in those 14 cases, including legal fees and settlement costs.

The Company’s subsidiary which owns the Bristol, Connecticut facility is involved in one of the 28 Superfund sites. As part of the acquisition of that facility, the seller and its now parent company, Cemex, S.A., agreed to indemnify the Company with respect to any liability for waste disposed of before the Company acquired the facility, which would include any liability arising from Superfund sites.

Eleven of the 28 Superfund sites involve subsidiaries acquired by the Company, which had been designated as PRPs with respect to such sites prior to acquisition of such subsidiaries by the Company. Some of these sites have been settled, and the Company believes its ultimate liability with respect to the remaining such sites will not be material to the Company’s result of operations, cash flow from operations or financial position.

As of June 30, 2005, the Company had reserves of $0.2 million for cleanup of Superfund sites not related to the CSD acquisition at which either the Company or a predecessor has been named as a PRP. However, there can be no guarantee that the Company’s ultimate liabilities for these sites will not materially exceed this amount or that indemnities applicable to any of these sites will be available to pay all or a portion of related costs.

EPA Enforcement Actions

Kimball Facility.  On April 2, 2003, Region VII of the U.S. Environmental Protection Agency (“EPA Region VII”) in Kansas City, Kansas, served a Complaint, Compliance Order and Notice of Opportunity for Hearing (“CCO”) on the Company’s subsidiary,

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which operates an incineration facility in Kimball, Nebraska. The CCO stems from an inspection of the Kimball facility between April 8 and 10, 2002. Thereafter, EPA Region VII issued a Notice of Violation (“NOV”) for certain alleged violations of RCRA. The Company responded to the NOV by letter and contested the allegations. After extensive settlement negotiations, on February 23, 2004, the Company and EPA Region VII executed a Consent Agreement and Final Order that included a Supplemental Environmental Project (“SEP”). The Company will be required to perform and account for the SEP in accordance with the EPA’s SEP Policy. The SEP will involve cleaning out chemicals from high school laboratories, art departments and other campus locations, with all such work to be performed by the Company’s own trained field chemists. The SEP will also include the proper packaging, labeling, manifesting, transportation, and ultimately disposal, recycling or re-use of these chemicals at the hazardous waste treatment, storage and disposal facilities owned and operated by the Company’s subsidiaries, in lieu of the payment of any further civil penalties. The Company will have two years to complete the performance of the SEP, and any remaining amounts then still owed and outstanding will have to be paid in cash at that time, as calculated pursuant to a sliding scale formula that reduces the amount of cash that will be owed as more of the environmental services are rendered over the two-year period. At June 30, 2005, the Company had accrued $132 thousand for its SEP liability.

Chicago Facility.  By letter dated January 16, 2004, Region V of the EPA (“EPA Region V”) in Chicago, Illinois notified the Company that EPA Region V believes the Company’s Chicago, Illinois facility may be in violation of the National Emission Standard for Benzene Waste Operations Subpart FF regulations promulgated under the Clean Air Act and that EPA Region V may seek injunctive relief and civil penalties for these alleged violations. The alleged violations pertain to total annual benzene quantity determinations and reporting, provisions of individual waste stream identification and emissions control information, and treatment and control requirements for the benzene waste streams. EPA Region V is seeking a fine of $325 thousand. The Company believes that its Chicago facility complies in all material respects with these regulations and has engaged in ongoing settlement discussions with EPA Region V to resolve the issues described in the letter from EPA Region V without litigation. The Company believes that the cost of resolving this matter will not be material to the Company’s results of operations or financial position.

State and Provincial Enforcement Actions

Chicago Facility.  On February 12, 2004, the Company’s subsidiary which owns the Chicago facility was notified by the Illinois Attorney General’s Office that an enforcement action was being initiated against such facility. The enforcement action alleges that the Chicago facility has violated its operating permit, certain Illinois Pollution Control Board regulations, and allegedly applicable provisions of the National Emission Standards for Hazardous Air Pollutants (“NESHAPs”). The Illinois Attorney General’s Office announced that it was seeking $170 thousand in penalties. Legal and compliance representatives of the Company have held discussions with the Illinois Attorney General’s Office and the Illinois Environmental Protection Agency, and anticipate that a Supplemental Environmental Project will be negotiated that will substantially reduce the cash component of the penalty in exchange for agreeing to the installation of equipment upgrades at the facility designed to address and control air emissions from operations. These negotiations are ongoing, and although significant progress has been made, there can be no assurance that a settlement can be reached or that the penalty will be reduced.

Aragonite, Utah Facility.  In February 2005, the Utah Department of Environmental Quality (“DEQ”) issued a Notice of Violation and Compliance Order (“NOVCO”) No. 0405013 against the Clean Harbors Aragonite, LLC incinerator, transfer station and storage facility located near Aragonite, Utah (“CH Aragonite”). The NOVCO pertains to hazardous waste compliance inspections conducted from October 2003 through September 2004 at CH Aragonite. CH Aragonite filed a detailed and comprehensive response to the NOVCO in April 2005. The DEQ assessed a proposed penalty of $129,860 and the Company is continuing to negotiate for a reduction in the fine.

London, Ontario Facility.  Clean Harbors Environmental Services Inc., and one of the Company’s Canadian subsidiaries, Clean Harbors Canada, Inc., received a summons alleging a number of regulatory offenses under the Ontario Occupational Health and Safety Act as a result of a fire in October 2003 at a Clean Harbors Canada, Inc., waste transfer facility in London, Ontario. A worker at the facility received serious injuries as a result of the fire. The initial appearance on this matter occurred on November 22, 2004. The Company has not yet determined whether to defend the charges or attempt to negotiate a settlement. The Company has not accrued any liability associated with this matter because any potential liability is not now estimable.

Summons To Respond to Environment Canada.   On July 15, 2005 a Summons was received by the Company’s Lambton Facility in Sarnia, Ontario, Canada requiring the Company to appear in an Ontario Court on September 19, 2005 to answer charges alleging that at various times between January, 2003 and June 2004, the Company failed to provide manifest copies to Environment Canada within three days after the manifest is provided to the first authorized carrier and failure to provide an inspector with outstanding manifests; importation of environmentally hazardous waste without an authorized carrier; and failure to submit notice information to the Minister.  Such alleged failures if true, would be contrary to: section 7(o) of the Export and Import of Hazardous Waste Regulations; section 272 (1)(a) of the Canadian Environmental Protection Act, 1999, c-33; paragraph 3(1) of the Environmental Emergency Regulations; section 32 (a) of the Export and Import of Hazardous Waste Regulations; section 30(a) of the Export and Import of Hazardous Wastes Regulations and section 13(1)(a) of the Transportation of Dangerous Goods Act, 1992.

At this time the information concerning this proceeding is in its preliminary stages and the Company expects to learn additional

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details concerning the alleged charges when counsel for the Company appear at the court proceeding on September 19, 2005. 

Contingency

Litigation Involving Former Holders of Subordinated Notes.  On April 30, 2001, the Company issued to John Hancock Life Insurance Company, Special Value Bond Fund, LLC, the Bill and Melinda Gates Foundation, and certain other institutional lenders (collectively, the “Lenders”) $35.0 million of 16% Senior Subordinated Notes due 2008 (the “Subordinated Notes”) as part of the Company’s refinancing of all its then outstanding indebtedness. Under the Securities Purchase Agreement dated as of April 12, 2001, between the Company and the Lenders (the “Purchase Agreement”), the Company was also required to pay a $350 thousand closing fee and issue to the Lenders warrants for an aggregate of 1,519,020 shares of the Company’s common stock (the “Warrants”) exercisable at any time prior to April 30, 2008 at an exercise price of $.01 per share. The Purchase Agreement contained covenants limiting (with certain exceptions) the Company’s ability to acquire other businesses or incur additional indebtedness without the consent of a majority in interest of the Lenders. The Purchase Agreement also provided that, if the Company should elect to prepay the Subordinated Notes prior to maturity, the Company would be obligated to pay a prepayment penalty which, in the case of a prepayment prior to April 30, 2004, would include a so-called “Make Whole Amount” computed using a discount rate 2.5% above the then current yield on United States government securities of equal maturity to the Subordinated Notes. The Purchase Agreement also provided that, if the Company should default on any of the terms of the Purchase Agreement including the covenants described above, the Lenders would have the right to call the Subordinated Notes for payment at an amount equal to the principal, accrued interest and the so-called “Make Whole Amount” then in effect.

During several months prior to the Company’s acquisition of the CSD assets effective September 7, 2002, the Company sought the Lenders’ cooperation with respect to such acquisition and to include the Lenders in a refinancing of the Company’s outstanding debt (which might involve leaving the Subordinated Notes outstanding or refinancing them). The Lenders, however, ultimately refused to provide any such cooperation. The Company thus notified the Lenders that it was proceeding with the acquisition of the CSD assets, which would be a violation of certain covenants in the Purchase Agreement, and the Lenders then called the Subordinated Notes for payment, including principal, interest and the “Make Whole Amount” of $16,991,129, an amount equal to 48.5% of the principal amount of the Subordinated Notes. In response to the Lenders’ demand, the Company immediately paid in full the amount demanded, while notifying the Lenders that it was paying the “Make Whole Amount” under protest. It is the Company’s position that if the payment to the Lenders is not deemed to be voluntary and the 48.5% “Make Whole Amount” is deemed unconscionable, the “Make-Whole Amount” is likely to be held unenforceable under Massachusetts case law.

Shortly after the closing of the acquisition of the CSD assets, the Company wrote to the Lenders demanding a return of the prepayment penalty, in response to which, on September 27, 2002, the Lenders filed a complaint in the Superior Court in Norfolk County, Dedham, Massachusetts asking the Court to determine the prepayment penalty to be valid and enforceable. On October 1, 2002, the Company filed a complaint in the Business Litigation Session of the Superior Court in Suffolk County, Boston, Massachusetts seeking a declaratory judgment that the “Make Whole Amount” is an unenforceable penalty and seeking an order for the return of the amount paid as a penalty, less the Lenders’ actual damages (if any), plus interest and costs. In the case of certain of the Lenders, the Company also seeks a judgment that those Lenders’ receipt of their share of the “Make Whole Amount,” the closing payment and the fair value of the Warrants constitutes a violation of applicable Massachusetts usury laws. The Company filed a motion seeking to consolidate both legal proceedings in the Business Litigation Session of the Superior Court in Suffolk County, Massachusetts, which motion was granted. Discovery in the proceedings was completed and all parties served and filed motions for summary judgment. On March 15, 2004, the Court granted summary judgment for the Lenders ruling that the “Make Whole Amount” was enforceable, and on May 15, 2004 the court ordered the Company pay $323 thousand to the Lenders for legal and expert cost reimbursement. The Company has appealed the Court’s rulings, and the Lenders have cross-appealed as to the amount of legal and expert cost reimbursement. The Appeals Court heard the appeals on March 5, 2005, but a decision by the Court is not expected for several months. The Company has not accrued the Lenders’ legal and expert costs because the Company now believes that such payment is not probable.

(8) Closure and Post-closure Liabilities

Reserves for closure and post-closure obligations are as follows (in thousands):

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All of the landfill facilities included in the table above are active as of June 30, 2005.

Anticipated payments at June 30, 2005 (based on current estimated costs) and anticipated timing of necessary regulatory approvals to commence work on closure and post-closure activities for each of the next five years and thereafter are as follows (in thousands):

The changes to closure and post-closure liabilities for the six months ended June 30, 2005 are as follows (in thousands):

18

The following table presents the change in remaining highly probable airspace from December 31, 2004 through June 30, 2005 (in thousands):

Asset retirement obligations incurred in 2005 are being discounted at the credit-adjusted risk-free rate of 10.25% and inflated at a rate of 2.16%.

As of December 31, 2004, there were three unpermitted expansions included in the Company’s landfill accounting model, which represents 32.4% of the Company’s remaining airspace at that date. Of these expansions, two do not represent exceptions to the Company’s established criteria. In March 2004, the Chief Financial Officer approved and the Audit Committee of the Board of Directors reviewed the inclusion of 7.8 million cubic yards of unpermitted airspace in highly probable airspace because it was determined that the airspace was highly probable even though the permit application will not be submitted within the next year. All of the other criteria were met for the inclusion of this airspace in highly probable airspace. Had the Company not included the 7.8 million cubic yards of unpermitted airspace in highly probable airspace, operating expense for the three and six months ended June 30, 2005 would have been higher by $136 thousand and $271 thousand, respectively.

(9) Remedial Liabilities

Remedial liabilities are obligations to investigate, alleviate or eliminate the effects of a release (or threat of a release) of hazardous substances into the environment and may also include corrective action under RCRA. The Company’s operating subsidiaries’ remediation obligations can be further characterized as Legal, Superfund, Long-term Maintenance and One-Time Projects. Legal liabilities are typically comprised of litigation matters that can involve certain aspects of environmental cleanup and can include third party claims for property damage or bodily injury allegedly arising from or caused by exposure to hazardous substances originating from Company activities or operations, or in certain cases, from the actions or inactions of other persons or companies. Superfund liabilities are typically claims alleging that the Company is a potentially responsible party and/or is potentially liable for environmental response, removal, remediation and cleanup costs at/or from either an owned or third party site. As described in Note 7, “Legal Proceedings,” Superfund liabilities also include certain Superfund liabilities to governmental entities for which the Company is potentially liable to reimburse the Sellers in connection with the Company’s 2002 acquisition of the CSD assets from Safety-Kleen Corp. Long-term Maintenance includes the costs of groundwater monitoring, treatment system operations, permit fees and facility maintenance for discontinued operations. One-Time Projects include the costs necessary to comply with regulatory requirements for the removal or treatment of contaminated materials.

SFAS No. 143 applies to asset retirement obligations that arise from ordinary business operations. The Company became subject to almost all of its remedial liabilities as part of the acquisition of the CSD assets from Safety-Kleen Corp., and the Company believes that the remedial obligations did not arise from normal operations. Remedial liabilities to which the Company became subject in connection with the acquisition of the CSD assets have been and will continue to be inflated using the inflation rate at the time of acquisition (2.4%) until the expected time of payment, then discounted at the risk-free interest rate at the time of acquisition (4.9%).  Remedial liabilities incurred subsequent to the acquisition and remedial liabilities that existed prior to the acquisition have been and will continue to be recorded at the estimated current value of the liability, which is usually neither increased for inflation nor reduced for discounting.

The Company records environmental-related accruals for remedial obligations at both its landfill and non-landfill operations. See Note 4 in the Annual Report filed on Form 10-K for the year ended December 31, 2004 for further discussion of the Company’s methodology for estimating and recording these accruals.

Reserves for remedial obligations are as follows (in thousands):

Anticipated payments (based on current estimated costs) and anticipated timing of necessary regulatory approvals to commence work on remedial activities for each of the next five years and thereafter are as follows (in thousands):