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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K

COMMISSION FILE NO. 001-34223

CLEAN HARBORS, INC.
(Exact name of registrant as specified in its charter)

Securities registered pursuant to Section 12(b) of the Securities Exchange Act of 1934:

Securities registered pursuant to Section 12(g) of the Securities Exchange Act of 1934:

None

         Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ý    No o

         Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes o    No ý

         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 has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes o    No o

         Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of the registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. o

         Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):

         Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o    No ý

         On June 30, 2009 (the last business day of the registrant's most recently completed second fiscal quarter), the aggregate market value of the voting and non-voting common stock of the registrant held by non-affiliates of the registrant was approximately $1.1 billion, based on the closing price of such common stock as of that date on the New York Stock Exchange. Reference is made to Part III of this report for the assumptions on which this calculation is based.

         On February 25, 2010, there were outstanding 26,249,155 shares of Common Stock, $.01 par value.

DOCUMENTS INCORPORATED BY REFERENCE

         Certain portions of the registrant's definitive proxy statement for its 2010 annual meeting of stockholders (which will be filed with the Commission not later than April 30, 2010) are incorporated by reference into Part III of this report.

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CLEAN HARBORS, INC.

ANNUAL REPORT ON FORM 10-K

YEAR ENDED DECEMBER 31, 2009

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Disclosure Regarding Forward-Looking Statements

        In addition to historical information, this annual report contains forward-looking statements, which are generally identifiable by use of the words "believes," "expects," "intends," "anticipates," "plans to," "estimates," "projects," or similar expressions. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those reflected in such forward-looking statements. Factors that might cause such a difference include, but are not limited to, those discussed in this report under Item 1A, "Risk Factors." Readers are cautioned not to place undue reliance on these forward-looking statements, which reflect managements' opinions only as of the date hereof. We undertake no obligation to revise or publicly release the results of any revision to these forward-looking statements. Readers should also carefully review the risk factors described in other documents which we file from time to time with the Securities and Exchange Commission (the "SEC"), including the quarterly reports on Form 10-Q to be filed by us during 2010.

PART I

ITEM 1.    BUSINESS

General

        Clean Harbors, Inc. and its subsidiaries (collectively, "we," "Clean Harbors" or the "Company") is a leading provider of environmental, energy and industrial services throughout North America. We serve over 50,000 customers, including a majority of Fortune 500 companies, thousands of smaller private entities and numerous federal, state, provincial and local governmental agencies. We have more than 175 locations, including over 50 waste management facilities, throughout North America in 36 U.S. states, seven Canadian provinces, Mexico and Puerto Rico. We also operate international locations in Bulgaria, China, Singapore, Sweden, Thailand and the United Kingdom.

        On July 31, 2009, we acquired 100% of the outstanding common shares of Eveready Inc. ("Eveready"), an Alberta corporation headquartered in Edmonton, Alberta. Eveready provides industrial maintenance and production, lodging, and exploration services to the oil and gas, chemical, pulp and paper, manufacturing and power generation industries. We anticipate this acquisition will enhance our presence in the energy and industrial services market, broaden the range of services we can offer customers, and advance our position in the Canadian marketplace.

        The purchase price of the acquisition totaled $410 million and included the issuance of 2.4 million shares of our common stock, assumption of $237 million of Eveready debt, and a cash payment of $56 million to the former Eveready shareholders. The acquisition was announced in April 2009, and as a condition to the approval of the acquisition by the Canadian Commissioner of Competition, we agreed to divest Eveready's Pembina Area Landfill, located near Drayton Valley, Alberta, due to its proximity to our existing landfill in the region.

        In connection with the closing of the Eveready acquisition, we re-aligned and expanded our reportable segments. This new structure reflects the way our management makes operating decisions and manages the growth and profitability of our business. The amounts presented for all prior periods throughout this report have been recast to reflect the impact of such changes. Under the new structure, we report our business in four operating segments, including:

•

Technical Services—provide a broad range of hazardous material management services including the packaging, collection, transportation, treatment and disposal of hazardous and non-hazardous waste at Company-owned incineration, landfill, wastewater, and other treatment facilities.

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•

Field Services—provide a wide variety of environmental cleanup services on customer sites or other locations on a scheduled or emergency response basis including tank cleaning, decontamination, remediation, and spill cleanup.



•

Industrial Services—provide industrial and specialty services, such as high-pressure and chemical cleaning, catalyst handling, decoking, material processing and industrial lodging services to refineries, chemical plants, pulp and paper mills, and other industrial facilities.



•

Exploration Services—provide exploration and directional boring services to the energy sector serving oil and gas exploration and production, and power generation.

        Technical Services and Field Services are included as part of Clean Harbors Environmental Services, and Industrial Services and Exploration Services are included as part of Clean Harbors Energy and Industrial Services.

        In connection with our acquisition of Eveready, we were required to obtain waivers from the lenders under our and Eveready's respective then existing credit agreements to allow for the completion of the acquisition and the repayment of Eveready's then outstanding 7% convertible subordinated debentures, and also concurrently with or following the acquisition to secure financing sufficient to pay off or restructure substantially all of the then remaining Eveready indebtedness. We obtained the necessary waivers prior to the closing of the acquisition and subsequently met the financing requirement on August 14, 2009 by issuing $300.0 million principal amount of 7⁵/8% senior secured notes for net proceeds of $292.1 million. We used most of the net proceeds of the offering to repay and terminate substantially all of the then outstanding Eveready debt (other than certain capital leases) assumed in connection with the acquisition and to pay related fees and expenses.

        Clean Harbors, Inc. was incorporated in Massachusetts in 1980 and our principal office is located in Norwell, Massachusetts. Effective December 15, 2008, shares of our common stock began trading on the New York Stock Exchange under the symbol CLH. Prior to that time, our stock was traded on The NASDAQ Global Select Market under the symbol CLHB. We maintain a website at the following Internet address: http://www.cleanharbors.com. Through a link on this website to the SEC website, http://www.sec.gov, we provide free access to our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 as soon as reasonably practicable after electronic filing with the SEC. Our guidelines on corporate governance, the charters for our Board Committees, and our code of ethics for members of the Board of Directors, senior officers and the chief executive officer are also available on our website, and we will post on our website any waivers of, or amendments to, such code of ethics. Our website and the information contained therein or connected thereto are not incorporated by reference into this annual report.

Health & Safety

        Health & Safety is our #1 priority—companywide. Employees at all levels of the Company share this philosophy and are committed to ensuring our safety goals are met. Our commitment to health and safety benefits everyone—our employees, our customers, the community, and the environment. Through the efforts of all our employees, we have implemented a successful health and safety-based culture that has continued to lower our Total Recordable Incident Rate ("TRIR"); Days Away, Restricted Activity and Transfer Rate ("DART"); and Experience Modification Rate ("EMR").

        In order to protect our employees, continue to lower our incident rates, and satisfy our customers' demands to retain the best service providers with the lowest TRIR, DART and EMR rates, we must continuously improve on our health and safety performance. To meet all of these requirements we launched SafetyFirst!, a comprehensive program companywide. SafetyFirst! is an employee-based program. All employees recognize the importance of protecting themselves, their fellow employees,

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their customers, and all those around them from harm. They demonstrate through their words and actions that they will reinforce acceptable safety practices and stop unsafe acts before those acts become a statistic. SafetyFirst! is not just a slogan—it's our commitment to keep the protection of our fellow workers in the forefront of everything we do.

Compliance

        We regard compliance with applicable environmental regulations as critical components of our overall operations. We strive to maintain the highest professional standards in our compliance activities. Our internal operating requirements are in many instances more stringent than those imposed by regulation. Our compliance program has been developed for each of our waste management facilities and service centers under the direction of our corporate staff. The compliance staff is responsible for facilities permitting and regulatory compliance, compliance training, transportation compliance, and related record keeping. To ensure the effectiveness of our regulatory compliance program, our compliance staff monitors daily operational activities and issues a monthly report to senior management concerning the status of environmental compliance and health and safety programs. We also have an Environmental Health and Safety Compliance Internal Audit Program designed to identify any weaknesses or opportunities for improvement in our ongoing compliance programs. We also perform periodic audits and inspections of the disposal facilities of other firms which we utilize.

        Our facilities are frequently inspected and audited by regulatory agencies, as well as by customers. Although our facilities have been cited on occasion for regulatory violations, we believe that each of our facilities is currently in substantial compliance with applicable requirements. Each of our major facilities and service centers has a full-time compliance representative to oversee the implementation of our compliance program at the facility or service center.

Strategy

        Our strategy is to develop and maintain ongoing relationships with a diversified group of customers who have recurring needs for environmental, energy or industrial services. We strive to be recognized as the premier supplier of a broad range of value-added services based upon quality, responsiveness, customer service, information technologies, breadth of service offerings and cost effectiveness.

        The principal elements of our business strategy are to:

•

Expand Service Offerings and Geographic Coverage—We believe our Technical and Field Services segments have a competitive advantage, particularly in areas where service centers are located at or near a treatment, storage and disposal facility ("TSDF"). By opening additional service centers in close proximity to our TSDFs, we believe that we can, with minimal capital expenditures, increase our market share within the Field Services segment. We believe this will drive additional waste to our existing facilities, thereby increasing utilization and enhancing overall profitability. Furthermore, we believe we can expand our Industrial and Exploration Services segments across a broader geographic area, thereby providing additional services to new markets.



•

Cross-Sell Across Segments—We believe the breadth of our service offerings allows us to provide additional services to existing customers. In particular, we believe we can provide energy and industrial services to customers which traditionally have only used our environmental services and environmental services to customers which traditionally have only used our energy and industrial services. We believe leveraging our ability to cross-sell environmental and energy and industrial services will drive increased revenue within our existing customer base.



•

Capture Large-Scale Projects—We provide turnkey offsite transportation and landfill or incineration disposal services for soil and other contaminated media generated from remediation

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activities. We also assist remediation contractors and project managers with support services including groundwater disposal, investigation derived waste disposal, rolloff container management, and many other related services. We believe this will drive incremental waste volume to our existing facilities, thereby increasing utilization and enhancing overall profitability.

•

Expand Throughput Capacity of Existing Waste Facilities—We operate an extensive network of hazardous waste management facilities and have made substantial investments in these facilities to date, which provide us with significant operating leverage as volumes increase. In addition, there are opportunities to expand waste handling capacity at these facilities by modifying the terms of the existing permits and by adding equipment and new technology. Through selected permit modifications, we can expand the range of treatment services offered to our customers without the large capital investment necessary to acquire or build new waste management facilities.



•

Pursue Selective Acquisitions—We actively pursue accretive "bolt-on" acquisitions in certain services or market sectors where we believe such acquisitions can enhance and expand our business with minimal capital outlay. We believe that we can expand existing services, especially in our non-disposal services, through strategic acquisitions in order to generate incremental revenues from existing and new customers and to obtain greater market share. We also continue to review other acquisition possibilities on a case-by-case basis.



•

Focus on Cost, Pricing and Productivity Initiatives—We continually seek to increase efficiency and to reduce costs in our business through enhanced technology, process efficiencies and stringent expense management.

Competitive Strengths

•

Leading Provider of Environmental, Energy and Industrial Services—We are one of the largest providers of environmental, energy and industrial services and the largest operator of non-nuclear hazardous waste treatment facilities in North America based on 2008 industry reports. We provide multi-faceted and low cost services to a broad mix of customers. We attract and better serve our customers because of our capabilities and the size, scale and geographic location of our assets, which allow us to serve multiple locations.



•

Large and Diversified Customer Base—Our customers range from Fortune 500 companies to midsize and small public and private entities that span multiple industries and business types, including governmental entities. This diversification limits our credit exposure to any one customer or industry.



•

Stable and Recurring Revenue Base—We have long-standing relationships with our customers. Our diversified customer base also provides stable and recurring revenues as a majority of our revenues are derived from previously served customers with recurring needs for our services. In addition, the costs to many of our customers of switching providers are high. This is due to many customers' desire to audit disposal facilities prior to their qualification as approved sites and to limit the number of facilities to which their wastes are shipped in order to reduce their potential liability under U.S. and Canadian environmental regulations. We have been selected as an approved vendor by large generators of waste because we possess comprehensive collection, recycling, treatment, transportation, disposal, and waste tracking capabilities and have the expertise necessary to comply with applicable environmental laws and regulations. Those customers that have selected us as an approved vendor typically continue to use our services on a recurring basis.



•

Comprehensive Service Capabilities—Our comprehensive service offerings allow us to act as a full-service provider to our customers. Our full-service orientation creates incremental revenue

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growth as customers seek to minimize the number of outside vendors and demand "one-stop" service providers. We also have the ability to cross-sell our energy and industrial services to customers who have traditionally used our environmental services, while also cross-selling environmental services to customers who have traditionally used our energy and industrial services. Our expanded geographic coverage maximizes the number of customer facilities that we can service.

•

Integrated Network of Assets—We operate, in the aggregate, the largest number of incinerators, landfills, treatment facilities and TSDFs in North America. Our broad service network enables us to effectively handle a waste stream from origin through disposal and to efficiently direct and internalize our waste streams to reduce costs. As our processing of wastes increase, our size allows us to increase our cash flow and earnings as we can internalize a greater volume of waste in our incinerators and landfills.



•

Regulatory Compliance—We continue to make capital investments in our facilities to ensure that they are in compliance with current federal, state, provincial and local regulations. Companies that rely on in-house disposal may find the current regulatory requirements to be too capital-intensive or complicated, and may choose to outsource many of their hazardous waste disposal needs.



•

Effective Cost Management—Our significant scale allows us to maintain low costs through standardized compliance procedures, significant purchasing power, research and development capabilities and our ability to efficiently utilize logistics and transportation to economically direct waste streams to the most efficient facility. We also have the ability to transport and process with internal resources the substantial majority of all hazardous waste that we manage for our customers. Finally, we are committed to reducing costs and have reduced headcount and other operating costs.



•

Proven and Experienced Management Team—Our executive management team provides depth and continuity. Our 16 executive officers collectively have over 194 years of experience in the environmental, energy and industrial services industries. Our Chief Executive Officer founded our Company in 1980, and the average tenure of the 15 other members of the executive management team exceeds 11 years.

Operations

General

        We report our business in the previously discussed four operating segments, which are Technical Services, Field Services, Industrial Services and Exploration Services.

        Seasonality and Cyclical Nature of Business.    Our operations may be affected by seasonal fluctuations due to weather and budgetary cycles influencing the timing of customers' spending for remedial activities. Typically during the first quarter of each year there is less demand for environmental services due to the cold weather, particularly in the Northern and Midwestern United States and Canada. Accordingly, reduced volumes of waste are received at our facilities and higher operating costs are associated with operating in sub-freezing weather and high levels of snowfall. In addition, factory closings for the year-end holidays reduce the volume of industrial waste generated, which results in lower volumes of waste handled by us during the first quarter of the following year.

        Conversely, typically during the first quarter of each year there is more demand for energy and industrial services due to the cold weather, particularly in Alberta, Canada, and less demand during the warmer months. The main reason for this is that the areas we service in Alberta are easier to access when the cold conditions make the terrain more suitable for companies to deploy their equipment. During the warmer months, thawing and mud conditions may impede deployment of equipment.

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        Geographical Information.    For the year ended December 31, 2009, we derived $787.9 million or 73.3% of revenues from customers located in the United States and Puerto Rico, $285.7 million or 26.6% of revenues from customers located in Canada, and less than 1.0% of revenues from customers in other international locations. For the year ended December 31, 2008, we derived approximately $897.2 million or 87.0% of revenues from customers located in the United States and Puerto Rico, approximately $132.8 million or 12.9% of revenues from customers located in Canada, and less than 1.0% of revenues from customers in Mexico.

Technical Services

        These services involve the collection, transport, treatment and disposal of hazardous and non-hazardous wastes, and include resource recovery, physical treatment, fuels blending, incineration, landfill disposal, wastewater treatment, lab chemical disposal, explosives management, and CleanPack® services. Our CleanPack services include the collection, identification and categorization, specialized packaging, transportation and disposal of laboratory chemicals and household hazardous wastes. Our technical services are provided through a network of service centers from which a fleet of trucks are dispatched to pick up customers' waste either on a predetermined schedule or on-demand, and to deliver the waste to permitted facilities, which are usually Company-owned. Our service centers can also dispatch chemists to a customer location for the collection of chemical and laboratory waste for disposal.

        Collection, Transportation and Logistics Management.    As an integral part of our services, we collect industrial wastes from customers and transport such wastes to and between our facilities for treatment or bulking for shipment to final disposal locations. Customers typically accumulate waste in containers, such as 55 gallon drums, bulk storage tanks or 20 cubic yard roll-off containers. In providing this service, we utilize a variety of specially designed and constructed tank trucks and semi-trailers as well as third-party transporters, including railroads.

        Treatment and Disposal.    We recycle, treat and dispose of hazardous and non-hazardous industrial wastes. The wastes handled include substances, which are classified as "hazardous" because of their corrosive, ignitable, infectious, reactive or toxic properties, and other substances subject to federal, state and provincial environmental regulation. We provide final treatment and disposal services designed to manage wastes which cannot be otherwise economically recycled or reused. The wastes we handle come in solid, sludge, liquid and gas form.

        We operate a network of TSDFs that collect, temporarily store and/or consolidate compatible waste streams for more efficient transportation to final recycling, treatment or disposal destinations. These facilities hold special permits, such as Part B permits under the Resource Conservation and Recovery Act ("RCRA") in the United States, which allows them to process waste through various technologies including recycling, incineration, and landfill and wastewater treatment. The types of waste we handle include:

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Flammables, combustibles and other organics;



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Acids and caustics;



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Reactive waste;



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Cyanides and sulfides;



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Industrial wastewaters;



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Items containing polychlorinated biphenyls ("PCBs"), such as utility transformers and electrical light ballasts;



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Other regulated wastes; and



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Non-hazardous industrial waste.

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        We receive detailed waste profiles prepared by our customers to document the nature of the waste. A sample of the delivered waste is tested to ensure that it conforms to the customer generated waste profile record and to select an appropriate method of treatment and disposal. Once the wastes are characterized, compatible wastes are consolidated to achieve economies in storage, handling, transportation and ultimate treatment and disposal. At the time of acceptance of a customer's waste at our facility, a unique computer "bar code" identification label is assigned to each container of waste, enabling the use of sophisticated computer systems to track and document the status, location and disposition of the waste.

        Resource Recovery and Fuels Blending.    We operate recycling systems for the reclamation and reuse of certain wastes, particularly solvent-based wastes generated by industrial cleaning operations, metal finishing and other manufacturing processes. Resource recovery involves the treatment of wastes using various methods, which effectively remove contaminants from the original material to restore its fitness for its intended purpose and to reduce the volume of waste requiring disposal.

        Spent solvents that can be recycled are processed through fractional distillation, thin film evaporation and other processes and are recovered into usable products. Upon recovery of these products, we either return the recovered solvents to the original generator or sell them to third parties. Organic liquids and solids with sufficient heat value are blended to meet strict specifications for use as supplemental fuels for incinerators, cement kilns, industrial furnaces and other high efficiency boilers. We have installed fuels blending equipment at some TSDFs to prepare these supplemental fuels. When possible, we burn fuel blended material at our incinerators. Otherwise, we send the fuel blended material to supplemental fuel users that are licensed to accept the blended fuel material. Although we pay a fee to the users that accept this product, this disposal method is substantially less costly than other disposal methods.

        Incineration.    Incineration is the preferred method for the treatment of organic hazardous waste, because it effectively destroys the contaminants at high temperatures. High temperature incineration effectively eliminates organic wastes such as herbicides, halogenated solvents, pesticides, and pharmaceutical and refinery wastes, regardless of whether they are gases, liquids, sludge or solids. Federal and state incineration regulations require a destruction and removal efficiency of 99.99% for most organic wastes and 99.9999% for PCBs and dioxins.

        We have six active incineration facilities that offer a wide range of technological capabilities to customers through this network. In the United States, we operate a fluidized bed thermal oxidation unit for maximum destruction efficiency of hazardous waste with an estimated annual capacity of 58,808 tons and three solids and liquids capable incineration facilities with a combined estimated annual capacity of 327,400 tons. We also operate two hazardous waste liquid injection incinerators in Canada with total annual capacity of approximately 165,000 tons.

        Our incineration facilities in Kimball, Nebraska, Deer Park, Texas, El Dorado, Arkansas and Aragonite, Utah are designed to process liquid organic wastes, sludge, solids, soil and debris. The Deer Park facility has two kilns and a rotary reactor. Our El Dorado, Arkansas incineration facility specializes in the treatment of bulk and containerized hazardous liquids, solids and sludge through two rotary kilns. Our incineration facilities in Kimball, Nebraska and Deer Park, Texas have on-site landfills for the disposal of ash produced as a result of the incineration process.

        Our incineration facilities in Mercier, Quebec and Lambton, Ontario are liquid injection incinerators, designed primarily for the destruction of liquid organic waste. Typical waste streams include wastewater with low levels of organics and other higher concentration organic liquid wastes not amenable to conventional physical or chemical waste treatment.

        Landfills.    Landfills are used primarily for the disposal of inorganic wastes. In the United States and Canada, we operate nine commercial landfills, excluding the Pembina Area Landfill which

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Eveready owned and operated but which we have agreed to divest. Seven of our commercial landfills are designed and permitted for the disposal of hazardous wastes and two of our landfills are operated for non-hazardous industrial waste disposal and, to a lesser extent, municipal solid waste. In addition to our commercial landfills, we also own and operate two non-commercial landfills that only accept waste from our on-site incinerators.

        Of our seven commercial landfills used for disposal of hazardous waste, five are located in the United States and two are located in Canada. As of December 31, 2009, the useful economic lives of these landfills include approximately 22.8 million cubic yards of remaining capacity. This estimate of the useful economic lives of these landfills includes permitted airspace and unpermitted airspace that our management believes to be probable of being permitted based on our analysis of various factors. In addition to the capacity included in the useful economic lives of these landfills, there are approximately 36.8 million cubic yards of additional unpermitted airspace capacity included in the footprints of these landfills that may ultimately be permitted. There can be no assurance that this unpermitted additional capacity will be permitted. In addition to the hazardous waste landfills, we operate two non-hazardous industrial landfills with 2.1 million cubic yards of remaining permitted capacity. These two facilities are located in the United States and have been issued operating permits under the authority of Subtitle D of RCRA. Prior to issuance of a permit, we must demonstrate to the permitting agency that our non-hazardous industrial landfills have, and must subsequently employ, operational programs protective of the integrity of the landfill, human health and the surrounding environment. Our non-hazardous landfill facilities are permitted to accept commercial industrial waste, including wastes from foundries, demolition and construction, machine shops, automobile manufacturing, printing, metal fabrications and recycling.

        Many of our landfills perform physical treatment of waste prior to final disposal. Physical treatment methods include separation and stabilization. These methods are used to reduce the volume or toxicity of waste material. Separation utilizes techniques such as sedimentation, filtration, flocculation and centrifugation to remove solid materials from liquids. Stabilization refers to a category of waste treatment processes designed to reduce contaminant mobility or solubility and convert waste to a more chemically stable form. Stabilization technology includes many classes of immobilization systems and applications. Stabilization is a frequent treatment method for metal bearing wastes received at several of our facilities, which treat the waste to meet specific federal land disposal restrictions. After treatment, the waste is tested to confirm that treatment standards have been met.

        Wastewater Treatment.    We operate seven wastewater treatment facilities that offer a range of wastewater treatment technologies. These wastewater treatment operations involve processing hazardous and non-hazardous wastes through the use of physical and chemical treatment methods. The solid waste materials produced by these wastewater processing operations are then disposed of at Company-owned facilities or select third party facilities, while the treated effluent is discharged to the local sewer system under permit.

        Our wastewater treatment facilities treat a broad range of industrial liquid and semi-liquid wastes containing heavy metals, organics and suspended solids, including:

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Acids and caustics;



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Ammonias, sulfides and cyanides;



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Heavy metals, ink wastes and plating solutions;



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Landfill leachate and scrubber waters; and



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Oily wastes and water soluble coolants.

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        Explosives Management.    We dispose of munitions and other explosives at our facility in Colfax, Louisiana. The Colfax facility is capable of treating a wide range of materials from fireworks and contaminated debris to rocket motors. Materials are managed in one of 20 permitted thermal treatment burn units. Residue is collected from the treatment process and shipped off-site for disposal at an approved facility. Metal by-products are shipped off-site for recycling.

Field Services

        These services provide customers with highly skilled experts who utilize specialty equipment and resources to perform services at any chosen location. Our field service crews and equipment are dispatched on a planned or emergency basis, and perform services such as confined space entry for tank cleaning, site decontamination, large remediation projects, demolition, spill cleanup, railcar cleaning, product recovery and transfer, scarifying and media blasting and vacuum services. Additional services include used oil and oil products recycling, as well as PCB management and disposal. Other services include filtration and water treatment services.

Industrial Services

        These services include a wide range of industrial maintenance services provided at refineries, chemical plants, pulp and paper mills, manufacturing, and power generation facilities, as well as production support services in the field for oil and gas companies. Many of our industrial services are provided within the oil sands region in Alberta, Canada. Our crews handle a variety of specialized industrial services including plant outage and turnaround services, decoking and pigging, catalyst handling, chemical cleaning, high and ultra-high pressure water cleaning, and large tank and surface impoundment cleaning. Our lodging and rentals services primarily consist of premier industrial lodges and drill camp accommodations for companies operating in the Alberta oil sands region. We also offer for rent or sale a variety of oilfield equipment including access rentals, well-site units, and production equipment. Other services include industrial health and safety services.

Exploration Services

        We provide a variety of services to support exploration programs for oil and gas companies. Some of the core services we offer include geospatial data imaging, line clearing, heli-portable and track drilling, seismic surveying, and land development. Our directional boring services support oil and gas companies and municipalities by installing pipeline, fiber optic, cable, gas, and water and sewer lines.

Other Services

        Apollo Onsite Services.    Our Apollo Onsite Services Program is an on-site solution that allows customers to outsource all or portions of their environmental management program. Select technicians work on a customer's site in tandem with the customer to deliver proper waste transportation and disposal, lab chemical packing, and field services and industrial services where appropriate. Whether a customer requires a single field technician or a multi-person team of diversified experience, we design a program to satisfy the customer's specific need. Additionally, the Apollo Onsite Services Program leverages our transportation and disposal assets by providing incremental volumes to process at our facilities.

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        Information Management Services.    Our Online Services allow customers free access to their waste information online, 24-hours per day, seven days per week. Customers can manage their waste profiles; run reports such as waste tracking reports and data for regulatory reporting; and have the ability to view, print or download signed manifests.

Competition

        The hazardous waste management industry in which we compete is highly competitive. The sources of competition vary by locality and by type of service rendered, with competition coming from national and regional waste services companies and hundreds of privately-owned firms. Philip Services Corp. (PSC), Veolia Environmental Services, and Waste Management, Inc. (WM) are the principal national firms with which we compete. Each of these competitors is able to provide one or more of the environmental services offered by us.

        In the United States, the original generators of hazardous waste remain liable under federal and state environmental laws for improper disposal of such wastes. Even if waste generators employ companies that have proper permits and licenses, knowledgeable customers are therefore interested in the reputation and financial strength of the companies they use for management of their hazardous wastes. We believe that our technical proficiency and reputation are important considerations to our customers in selecting and continuing to utilize our services.

        We believe that the depth of our recycling, treatment and disposal capabilities and our ability to collect and transport waste products efficiently, quality of service, safety, and pricing are the most significant factors in the market for treatment and disposal services.

        For our technical and field services, competitors include several major national and regional environmental services firms, as well as numerous smaller local firms. We believe the availability of skilled technical professional personnel, quality of performance, diversity of services and price are the key competitive factors in this service industry.

        The energy and industrial services industry in which we compete is also highly competitive. The sources of competition vary by locality and by type of service rendered, with competition coming from national and regional service providers, and hundreds of privately-owned firms that offer energy or industrial services. CEDA International Corporation and Newalta in Canada, and Philip Services Corp. (PSC) and Veolia Environmental Services in the United States, are the principal national firms with which we compete. Each of these competitors is able to provide one or more of the energy or industrial services offered by us. We believe the availability of specialized equipment, skilled technical professional personnel, quality of performance, diversity of services and price are the key competitive factors in this service industry.

        The principal methods of competition for all of our services are price, quality, reliability of service rendered and technical proficiency. We believe that we offer a more comprehensive range of environmental, energy and industrial services than our competitors in major portions of our service territory, and that our ability to provide comprehensive services supported by unique information technologies capable of managing the customers' overall environmental programs constitutes a significant advantage.

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Employees

        As of December 31, 2009, we employed approximately 6,399 active full-time employees, of which 647 employees (10%) are represented by labor unions. We believe that our relationship with our employees is satisfactory.

        As part of our commitment to employee safety and quality customer service, we have an extensive compliance program and a trained environmental, health and safety staff. We adhere to a risk management program designed to reduce potential liabilities to us and to our customers.

Intellectual Property

        We have invested significantly in the development of proprietary technology and also to establish and maintain an extensive knowledge of leading technologies and incorporate these technologies into the services we offer and provide to our customers. We hold a total of 15 U.S. and 12 foreign patents (which will expire between 2010 and 2024), and 16 U.S. and three foreign trademarks. We also license software and other intellectual property from various third parties. We enter into confidentiality agreements with certain of our employees, consultants and corporate partners, and control access to software documentation and other proprietary information. We believe that we hold adequate rights to all intellectual property used in our business and that we do not infringe upon any intellectual property rights held by other parties.

Management of Risks

        We adhere to a program of risk management policies and practices designed to reduce potential liability, as well as to manage customers' ongoing environmental exposures. This program includes installation of risk management systems at our facilities, such as fire suppression, employee training, environmental, auditing and policy decisions restricting the types of wastes handled. We evaluate all revenue opportunities and decline those that we believe involve unacceptable risks.

        We dispose of waste at our incineration, wastewater treatment and landfill facilities, or at facilities owned and operated by other firms that we have audited and approved. Typically, we apply established technologies to the treatment, storage and recovery of hazardous wastes. We believe our operations are conducted in a safe and prudent manner and in substantial compliance with applicable laws and regulations.

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Insurance and Financial Assurance

        Our insurance programs cover the potential risks associated with our multifaceted operations from two primary exposures: direct physical damage and third party liability. We maintain a casualty insurance program providing coverage for vehicles, employer's liability and commercial general liability in the aggregate amount of $55.0 million, $52.0 million and $52.0 million, respectively, per year, subject to a retention of $0.5 million per occurrence. We also have workers' compensation insurance whose limits are established by state statutes. Since the early 1980s, casualty insurance policies have typically excluded liability for pollution, which is covered under a separate pollution liability program; however, our auto liability policy does provide the first $5.0 million of transportation pollution insurance.

        We have pollution liability insurance policies covering potential risk in three areas: as a contractor performing services at customer sites, as a transporter of waste and for waste processing at our facilities. The contractor's pollution liability insurance has limits of $15.0 million per occurrence and $25.0 million in the aggregate, covering offsite remedial activities and associated liabilities. A $0.25 million deductible applies to this policy.

        For in-transit pollution liability, the pollution liability policy provides coverage for up to $45.0 million per occurrence and $55.0 million aggregate excess above the primary $5.0 million auto liability policy. The combined policies provide us with coverage for up to $50.0 million per occurrence and $60.0 million aggregate for sudden and accidental occurrences during transportation of waste from the time waste is picked up from a customer until its delivery to the final disposal site. A $0.5 million deductible applies to this coverage.

        Federal and state regulations require liability insurance coverage for all facilities that treat, store or dispose of hazardous waste. RCRA, the Toxic Substances Control Act, and comparable state hazardous waste regulations typically require hazardous waste handling facilities to maintain pollution liability insurance in the amount of $1.0 million per occurrence and $2.0 million in the aggregate for sudden occurrences, and $3.0 million per occurrence and $6.0 million in the aggregate for non-sudden occurrences. Steadfast Insurance Company (a unit of Zurich Insurance N.A.) provides insurance for our treatment, storage and disposal activities that meet the regulatory requirements. In addition, this policy provides excess limits above the regulatory requirements up to $30.0 million.

        Under our insurance programs, coverage is obtained for catastrophic exposures as well as those risks required to be insured by law or contract. It is our policy to retain a significant portion of certain expected losses related primarily to employee benefit, workers' compensation, commercial general and vehicle liability. Provisions for losses expected under these programs are recorded based upon our estimates of the actuarial promulgation of the aggregate liability for claims. We believe that policy cancellation terms are similar to those of other companies in other industries.

        Operators of hazardous waste handling facilities are also required by federal, state and provincial regulations to provide financial assurance for closure and post-closure care of those facilities should the facilities cease operation. Closure would include the cost of removing the waste stored at a facility which ceased operating and sending the material to another facility for disposal and the cost of performing certain procedures for decontamination of the facilities. The total amount of the closure and post-closure financial assurance which we have been required by regulators to provide is approximately $319.7 million for U.S. facilities and $22.7 million for Canadian facilities. We have placed the required financial assurance for closure through a qualified insurance company, Steadfast Insurance Company.

Environmental Regulation

        While our business has benefited substantially from increased governmental regulation of hazardous waste transportation, storage and disposal, the environmental services industry itself has

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become the subject of extensive and evolving regulation by federal, state, provincial and local authorities. We are required to obtain federal, state, provincial and local permits or approvals for each of our hazardous waste facilities. Such permits are difficult to obtain and, in many instances, extensive studies, tests, and public hearings are required before the approvals can be issued. We have acquired all operating permits and approvals now required for the current operation of our business, and have applied for, or are in the process of applying for, all permits and approvals needed in connection with continued operation and planned expansion or modifications of our operations.

        We make a continuing effort to anticipate regulatory, political and legal developments that might affect operations, but are not always able to do so. We cannot predict the extent to which any environmental legislation or regulation that may be enacted or enforced in the future may affect our operations.

United States Hazardous Waste Regulation

        Federal Regulations.    The most significant federal environmental laws affecting us are the Resource Conservation and Recovery Act ("RCRA"), the Comprehensive Environmental Response, Compensation and Liability Act ("CERCLA"), also known as the "Superfund Act," the Clean Air Act, the Clean Water Act, and the Toxic Substances Control Act ("TSCA").

        RCRA.    RCRA is the principal federal statute governing hazardous waste generation, treatment, transportation, storage and disposal. Pursuant to RCRA, the U.S. Environmental Protection Agency (the "EPA") has established a comprehensive "cradle-to-grave" system for the management of a wide range of materials identified as hazardous or solid waste. States that have adopted hazardous waste management programs with standards at least as stringent as those promulgated by the EPA have been delegated authority by the EPA to administer their facility permitting programs in lieu of the EPA's program.

        Every facility that treats, stores or disposes of hazardous waste must obtain a RCRA permit from the EPA or an authorized state agency, unless a specific exemption exists, and must comply with certain operating requirements. Under RCRA, hazardous waste management facilities in existence on November 19, 1980 were required to submit a preliminary permit application to the EPA, the so-called Part A Application. By virtue of this filing, a facility obtained interim status, allowing it to operate until licensing proceedings are instituted pursuant to more comprehensive and exacting regulations (the Part B permitting process). Interim Status facilities may continue to operate pursuant to the Part A Application until their Part B permitting process is concluded.

        RCRA requires that Part B permits contain provisions for required on-site study and cleanup activities, known as "corrective action," including detailed compliance schedules and provisions for assurance of financial responsibility. See Note 8, "Closure and Post-Closure Liabilities," and Note 9, "Remedial Liabilities," to our consolidated financial statements included in Item 8, "Financial Statements and Supplementary Data," for a discussion of our environmental liabilities. See "Insurance and Financial Assurance" above for a discussion of our financial assurance requirements.

        The Superfund Act.    The Superfund Act is the primary federal statute regulating the cleanup of inactive hazardous substance sites and imposing liability for cleanup on the responsible parties. It also provides for immediate response and removal actions coordinated by the EPA to releases of hazardous substances into the environment, and authorizes the government to respond to the release or threatened release of hazardous substances or to order responsible persons to perform any necessary cleanup. The statute provides for strict, and in certain cases, joint and several liability for these responses and other related costs, and for liability for the cost of damages to natural resources, to the parties involved in the generation, transportation and disposal of such hazardous substances. Under the statute, we may be deemed liable as a generator or transporter of a hazardous substance which is released into the environment, or as the owner or operator of a facility from which there is a release of

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a hazardous substance into the environment. See Note 18, "Commitments and Contingencies," to our consolidated financial statements included in Item 8, "Financial Statements and Supplementary Data," for a description of the principal such proceedings in which we are involved.

        The Clean Air Act.    The Clean Air Act was passed by Congress to control the emissions of pollutants into the air and requires permits to be obtained for certain sources of toxic air pollutants such as vinyl chloride, or criteria pollutants, such as carbon monoxide. In 1990, Congress amended the Clean Air Act to require further reductions of air pollutants with specific targets for non-attainment areas in order to meet certain ambient air quality standards. These amendments also require the EPA to promulgate regulations, which (i) control emissions of 189 hazardous air pollutants; (ii) create uniform operating permits for major industrial facilities similar to RCRA operating permits; (iii) mandate the phase-out of ozone depleting chemicals; and (iv) provide for enhanced enforcement.

        In 2009 the EPA enacted regulations under its Clean Air Act authority requiring the mandatory reporting from all sources that emit 25,000 tons per year of greenhouse gasses. The regulations are administrative in nature and do not place any restrictions on our operations. We have evaluated each of our operations and determined that compliance with these new regulations will not have a material impact on our operations.

        The Clean Water Act.    This legislation prohibits discharges into the waters of the United States without governmental authorization and regulates the discharge of pollutants into surface waters and sewers from a variety of sources, including disposal sites and treatment facilities. The EPA has promulgated "pretreatment" regulations under the Clean Water Act, which establish pretreatment standards for introduction of pollutants into publicly owned treatment works. In the course of the treatment process, our wastewater treatment facilities generate wastewater, which we discharge to publicly owned treatment works pursuant to permits issued by the appropriate governmental authority. We are required to obtain discharge permits and conduct sampling and monitoring programs. We believe each of our operating facilities complies in all material respects with the applicable requirements.

        In December 2000, the EPA promulgated new effluent limitations, pretreatment standards and source performance standards for centralized wastewater treatment facilities. Centralized wastewater treatment facilities receive and treat a wide variety of hazardous and non-hazardous wastewaters from offsite companies and discharge the treated water directly to waterways or to municipal sewer systems. These rules set stringent limits for the discharge of metals, organic compounds and oil. All of our wastewater treatment facilities were affected by these rules and were in substantial compliance with the discharge standards by December 2004.

        TSCA.    We also operate a network of collection, treatment and field services (remediation) activities throughout North America that are regulated under provisions of TSCA. TSCA established a national program for the management of substances classified as PCBs, which include waste PCBs as well as RCRA wastes contaminated with PCBs. The rules set minimum design and operating requirements for storage, treatment and disposal of PCB wastes. Since their initial publication, the rules have been modified to enhance the management standards for TSCA-regulated operations including the decommissioning of PCB transformers and articles; detoxification of transformer oils; incineration of PCB liquids and solids; landfill disposal of PCB solids; and remediation of PCB contamination at customer sites.

        Other Federal Laws.    In addition to regulations specifically directed at the transportation, storage, and disposal facilities, there are a number of regulations that may "pass-through" to the facilities based on the acceptance of regulated waste from affected client facilities. Each facility that accepts affected waste must comply with the regulations for that waste, facility or industry. Examples of this type of regulation are National Emission Standards for Benzene Waste Operations and National Emissions

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Standards for Pharmaceuticals Production. Each of our facilities addresses these regulations on a case-by-case basis determined by its ability to comply with the pass-through regulations.

        In our transportation operations, we are regulated by the U.S. Department of Transportation, the Federal Railroad Administration, the Federal Aviation Administration and the U.S. Coast Guard, as well as by the regulatory agencies of each state in which we operate or through which our vehicles pass.

        Health and safety standards under the Occupational Safety and Health Act ("OSHA") are applicable to all of our operations in all four of our segments.

        State and Local Regulations.    Pursuant to the EPA's authorization of their RCRA equivalent programs, a number of U.S. states have regulatory programs governing the operations and permitting of hazardous waste facilities. Accordingly, the hazardous waste treatment, storage and disposal activities of a number of our facilities are regulated by the relevant state agencies in addition to federal EPA regulation.

        Some states classify as hazardous some wastes that are not regulated under RCRA. For example, Massachusetts considers used oil as "hazardous wastes" while RCRA does not. Accordingly, we must comply with state requirements for handling state regulated wastes, and, when necessary, obtain state licenses for treating, storing, and disposing of such wastes at our facilities.

        We believe that each of our facilities is in substantial compliance with the applicable requirements of federal and state laws, the regulations thereunder, and the licenses which we have obtained pursuant thereto. Once issued, such licenses have maximum fixed terms of a given number of years, which differ from state to state, ranging from three to ten years. The issuing state agency may review or modify a license at any time during its term. We anticipate that once a license is issued with respect to a facility, the license will be renewed at the end of its term if the facility's operations are in compliance with applicable requirements. However, there can be no assurance that regulations governing future licensing will remain static, or that we will be able to comply with such requirements.

        Our wastewater treatment facilities are also subject to state and local regulation, most significantly sewer discharge regulations adopted by the municipalities which receive treated wastewater from the treatment processes. Our continued ability to operate our liquid waste treatment process at each such facility is dependent upon our ability to continue these sewer discharges.

        Our facilities are regulated pursuant to state statutes, including those addressing clean water and clean air. Local sewer discharge and flammable storage requirements are applicable to certain of our facilities. Our facilities are also subject to local siting, zoning and land use restrictions. Although our facilities occasionally have been cited for regulatory violations, we believe we are in substantial compliance with all federal, state and local laws regulating our business.

Canadian Hazardous Waste Regulation

        In Canada, the provinces retain control over environmental issues within their boundaries and thus have the primary responsibility for regulating management of hazardous wastes. The federal government regulates issues of national scope or where activities cross provincial boundaries.

        Provincial Regulations.    Most of Canada's industrial development and the major part of its population are located in four provinces: Ontario, Quebec, Alberta and British Columbia. These provinces have the most detailed environmental regulations. We operate major waste management facilities in each of these provinces, as well as waste transfer facilities in Nova Scotia and Manitoba.

        The main provincial acts dealing with hazardous waste management are:

•

Ontario—Environmental Protection Act;



•

Quebec—Environmental Quality Act;

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•

Alberta—Environmental Protection and Enhancement Act; and



•

British Columbia—Waste Management Act.

        These pieces of legislation were developed by the provinces totally independently and, among other things, generally control the generation, characterization, transport, treatment and disposal of hazardous wastes. Regulations developed by the provinces under the relevant legislation are also developed independently, but are often quite similar in effect and sometimes in application. For example, there is some uniformity in manifest design and utilization.

        Provincial legislation also provides for the establishment of waste management facilities. In this case, the facilities are also controlled by provincial statutes and regulations governing emissions to air, groundwater and surface water and prescribing design criteria and operational guidelines.

        On August 12, 2005, the Ontario Ministry of the Environment adopted new regulations which prohibit land disposal of untreated hazardous waste and require the waste to meet specific treatment standards prior to land disposal. Land disposal includes onsite and offsite land filling, land farming and any other form of land disposal. These requirements are similar to the RCRA Land Disposal Restrictions, or "LDR," enacted in the United States and thus bring the Province of Ontario in closer conformity with the United States regulatory scheme. The new Ontario LDR commenced in 2007 through a phased-in schedule based on specific inorganic waste streams, and are now fully implemented with the regulation of organic waste streams that became effective at the end of 2009.

        We carefully analyzed the new regulations to determine their impact on our operations in Ontario and made a series of operational improvements at our Lambton landfill facility aimed at receiving all waste regulated under the new LDR and applying treatment technologies to compliantly dispose of the waste at the landfill. These operational improvements included the construction of a new totally enclosed LDR waste treatment and stabilization building which was completed in September 2007 under a Certificate of Approval from the Ontario Ministry of the Environment. These modifications allow us to compliantly accept, treat and dispose of inorganic streams subject to the new LDR. The Ministry also approved a series of proprietary organic waste treatment methods that allow the Lambton facility to accept, for example, spent aluminum pot liner waste for pre-treatment, followed by LDR-compliant disposal within the landfill. Additionally, the Ministry has approved various disposal methodologies associated with the management of debris contaminated with organic chemical constituents subject to LDR regulation. We continue to evaluate other potential customer waste streams subject to the new LDR standards and modify on-site waste treatment processes to accommodate these streams at the Lambton landfill.

        Waste transporters require a permit to operate under provincial waste management regulations and are subject to the requirements of the Federal Transportation of Dangerous Goods legislation. They are required to report the quantities and disposition of materials shipped.

        Within the provincial regulations, definitions of hazardous wastes are quite similar. Wastes can be defined as hazardous based on origin or characteristic and the descriptions or parameters involved are very similar to those in effect in the United States. A major difference between the United States regulatory regime and those in Canada relates to ownership and liability. Under Canadian provincial regulations, ownership changes when waste is transferred to a properly permitted third party carrier and subsequently to an approved treatment and disposal facility. This means that the generator is no longer liable for improper handling, treatment or disposal, responsibility having been transferred to the carrier or the facility. Exceptions may occur if the carrier is working under contract to the generator or if the waste is different from that which was originally contracted among the parties.

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        Canadian Federal Regulations.    The Canadian federal government has authority for those matters which are national in scope and in impact and for Canada's relations with other nations. The main federal laws governing hazardous waste management are:

•

Canadian Environmental Protection Act (1999) ("CEPA 99"), and



•

Transportation of Dangerous Goods Act.

        Environment Canada is the federal agency with responsibility for environmental matters and the main legislative instrument is the Canadian Environmental Protection Act. This act charges Environment Canada and Health Canada with protection of human health and the environment and seeks to control the production, importation and use of substances in Canada and to control their impact on the environment.

        The Export and Import of Hazardous Wastes Regulations under CEPA 99 control the export and import of hazardous wastes and hazardous recyclable materials. By reference, these regulations incorporate the Transportation of Dangerous Goods Act and Regulations, which address identification, packaging, marking and documentation of hazardous materials during transport. CEPA 99 requires that anyone proposing to export or import hazardous wastes or hazardous recyclable materials or to transport them through Canada notify the Minister of the Environment and obtain a permit to do so. Section 9 of CEPA 99 allows the federal government to enter into administrative agreements with the provinces and territories for the development and improvement of environmental standards. These agreements represent cooperation towards a common goal rather than a delegation of authority under CEPA 99. To facilitate the development of provincial and territorial agreements, the federal, provincial and territorial governments participate in the Canadian Council of Ministers of the Environment ("CCME"). The CCME comprises the 14 environment ministers from the federal, provincial and territorial governments, who normally meet twice a year to discuss national environmental priorities and to determine work to be carried out under the auspices of the CCME.

        In 2004, Environment Canada implemented mandatory greenhouse gas reporting under CEPA 99. Under CEPA 99, mandatory reporting was required if a facility emitted more than 100,000 Canadian tonnes of carbon dioxide equivalent per year. As of July 11, 2009, the reporting threshold under CEPA 99 was reduced to 50,000 Canadian tonnes of carbon dioxide equivalent. The reduction in reporting limits will subject certain of the Company's Canadian facilities to the new reporting requirements, but the Company does not believe the new requirements will have a material impact on operations.

        Canadian Local and Municipal Regulations.    Local and municipal regulations seldom reference direct control of hazardous waste management activities. Municipal regulations and by-laws, however, control such issues as land use designation, access to municipal services and use of emergency services, all of which can have a significant impact on facility operation.

Compliance with Environmental Regulations

        We incur costs and make capital investments in order to comply with the previously discussed environmental regulations. These regulations require that we remediate contaminated sites, operate our facilities in accordance with enacted regulations, obtain required financial assurance for closure and post-closure care of our facilities should such facilities cease operations, and make capital investments in order to keep our facilities in compliance with environmental regulations.

        As discussed in Note 8, "Closure and Post-Closure Liabilities," and Note 9, "Remedial Liabilities," to our consolidated financial statements included in Item 8, "Financial Statements and Supplementary Data," we have accrued environmental liabilities as of December 31, 2009, of $181.3 million, substantially all of which we assumed in connection with our acquisitions of the assets of the Chemical Services Division (the "CSD assets") of Safety-Kleen Corp. in 2002, Teris LLC in 2006, and one of the

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two solvent recycling facilities we purchased from Safety-Kleen Systems, Inc. in 2008. Such amount does not include approximately $3.0 million of additional environmental liabilities which relate to the Pembina Area Landfill which Eveready owned and operated but which we have agreed to divest. For the years ended December 31, 2009 and 2008, we spent $8.6 million and $14.3 million, respectively, to address environmental liabilities, almost all of the spending related to the environmental liabilities assumed as part of the acquisition of the CSD assets and Teris. The decrease in the year-over-year spending was primarily due to the settlement during 2008 of legal and administrative proceedings relating to our Plaquemine, Louisiana property and the Helen Kramer Superfund site.

        As discussed more fully above under the heading "Insurance and Financial Assurance," we are required to provide financial assurance with respect to certain statutorily required closure, post-closure and corrective action obligations at our facilities. We have placed the required financial assurance through a qualified insurance company, Steadfast Insurance Company (a unit of Zurich N.A.).

        As described in Note 18, "Commitments and Contingencies," to our consolidated financial statements included in Item 8, "Financial Statements and Supplementary Data," we are involved in legal proceedings arising under environmental laws and regulations. Alleged failure to comply with laws and regulations may lead to the imposition of fines or the denial, revocation or delay of the renewal of permits and licenses by governmental entities. In addition, such governmental entities, as well as surrounding landowners, may claim that we are liable for environmental damages. Citizens groups have become increasingly active in challenging the grant or renewal of permits and licenses for hazardous waste facilities, and responding to such challenges has further increased the costs associated with establishing new facilities or expanding current facilities. A significant judgment against us, the loss of a significant permit or license or the imposition of a significant fine could have a material adverse effect on our business and future prospects.

ITEM 1A.    RISK FACTORS

        An investment in our securities involves certain risks, including those described below. You should consider carefully these risk factors together with all of the information included in this report before investing in our securities. The information below includes updated discussions with respect to changes which have occurred in our risk factors as a result of our acquisition on July 31, 2009 of Eveready Inc., or "Eveready," and the related significant expansion of our energy and industrial services business, our entry on July 31, 2009 into an amended $120.0 million revolving credit facility, or the "new revolving credit facility," and our issuance on August 14, 2009 of $300.0 million principal amount of 7⁵/8% senior secured notes, or the "notes."

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

Our businesses are subject to operational and insurance risks.

        Provision of both environmental services and energy and industrial services to our customers is subject to such risks as equipment defects, malfunctions and failures, and natural disasters. These risks expose us to potential liability for personal injury, loss of life, business interruption, property damage or destruction, pollution and other environmental damages. 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 if we were to incur such liabilities 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.

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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 provide. The current downturn in economic conditions, particularly with respect to manufacturing and oil and gas production, has caused increased competition for market share, which could result in lower prices and reduced gross margins from the services we provide and negatively affect our ability to grow or sustain our current revenue and profit levels in the future.

The provision of our services involves significant safety risks.

        Our employees often work under potentially hazardous conditions, and we must maintain a solid safety record in order to remain a preferred supplier to our major customers. In order to protect our employees and meet such customer demands, we have instituted an active safety program supported by continual practice and training. However, should our safety record deteriorate, we could be subject to potential liabilities and a reduction of revenues from our major customers.

Our businesses are subject to 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.

Seasonality makes it harder for us to manage our businesses and for investors to evaluate our performance.

        Our business operations are affected by seasonal fluctuations due to weather and budgetary cycles influencing the timing of customers' spending for our services. Typically during the first quarter of each calendar year, there is less demand for environmental remediation due to weather-related reasons, particularly in the northern and midwestern United States and Canada, and an increased possibility of unplanned weather-related plant shutdowns. Conversely, because a large portion of our energy and industrial services business is carried out in Western Canada and involves moving heavy equipment, our ability to provide such services is dependent on weather conditions. Thawing in the spring renders many secondary roads incapable of supporting heavy equipment, and extremely cold weather in the winter season or wet weather during any season can limit our ability to provide timely services. As a result, the operating performance of our energy and industrial services business also tends to be seasonal (with higher revenues during the first quarter of each year and reduced revenues during the second quarter) and may be negatively impacted by adverse weather conditions during any quarter. This seasonality makes it harder for us to manage our businesses and for investors to evaluate our performance.

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 long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. At the end of each of 2009, 2008 and 2007, 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.

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Risks Particularly Affecting Our Environmental Services Business

We assumed significant environmental liabilities as part of past acquisitions, and 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 now estimated.

        We have accrued environmental liabilities valued as of December 31, 2009, at $181.3 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. This amount does not include approximately $3.0 million of additional environmental liabilities related to the Pembina Area Landfill which Eveready owned and operated that we have agreed to divest. We calculate our environmental liabilities on a present value basis in accordance with generally accepted accounting principles (which takes into consideration both the amount of such liabilities and the timing when it is projected that we will be required to pay such liabilities). We anticipate our environmental liabilities will be payable over many years and that cash flows generated from our operations will generally be sufficient to fund the payment of such liabilities when required. However, events not now anticipated (such as future changes in environmental laws and regulations or their enforcement) could require that such payments be made earlier or in greater amounts than now estimated, which could adversely affect our financial condition and results of operations.

If we are unable to obtain at reasonable cost the insurance, surety bonds and financial assurances which are required for our operations, our business and results of operations would be adversely affected.

        We purchase insurance, occasionally post bid and performance bonds, and 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. As of December 31, 2009, our total estimated closure and post-closure costs requiring financial assurance by regulators (excluding Eveready's estimated costs as described below) were $319.7 million for our U.S. facilities and $22.7 million for our Canadian facilities. We have placed all of the required financial assurance through a qualified insurance company, Steadfast Insurance Company (a unit of Zurich Insurance N.A.), or "Steadfast." The U.S. facilities are insured with an insurance policy written by Steadfast which expires in 2013. The Canadian facilities utilize surety bonds provided through Zurich Insurance Company (Canada), which expire at various dates throughout 2010.

        As of July 31, 2009, Eveready had outstanding letters of credit of $1.9 million that were issued to comply with certain environmental regulations relating to Eveready's closure and post-closure costs. We replaced two of the three letters of credit for $1.2 million with surety bonds and the remaining outstanding letter of credit as of December 31, 2009 will be replaced with a letter of credit under our current credit facility in the first quarter of 2010.

        Our ability to continue conducting our operations would be adversely affected if we became unable to obtain sufficient insurance, surety bonds or other financial assurances at reasonable cost to meet our business and regulatory requirements in the future. The availability of insurance could be affected by factors outside of our control as well as the insurers' or sureties' assessment of our risk. If we should become unable to obtain such letters of credit under our financial arrangements, we might be unable to obtain sufficient insurance or other financial assurances.

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

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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. The hazardous and industrial waste management business is also cyclical 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 major remedial projects and regulatory developments over which we have no control.

        Our operations are significantly affected by the commencement and completion of major remedial projects; cleanup of major spills or other events; 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 remedial market; 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.

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

        Our operations and those of others in the environmental services industry involve the handling of dangerous and hazardous materials, and 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 cleanups of soil and groundwater contamination. While increasing environmental regulation often presents new business opportunities for us, it often 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, and that generate those materials and arrange for their disposal or treatment at contaminated sites. Such liabilities can relate to 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

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power to suspend or revoke permits or licenses needed for operation of our plants, equipment, and vehicles based on, among other factors, our compliance record, and customers may decide not to use a particular disposal facility or do business with us because of concerns about our compliance record. Suspension or revocation of permits or licenses would impact our operations and could have a material adverse impact on 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 sites and paying a portion of the remediation costs at certain sites owned by third parties. While, based on available information, we do not believe these remedial activities will result in a material adverse effect upon our operations or financial condition, these activities or the discovery of previously unknown conditions could result in material costs.

        Environmental and land use laws also impact our ability to expand. 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 applicable environmental law, 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.

        We may make further acquisitions from time to time in the future, and we have tried and will continue to try to evaluate and limit environmental risks and liabilities presented by businesses or facilities to be acquired prior to the acquisition. It is possible that 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 anticipate. It is also possible that government officials responsible for enforcing environmental laws may believe an issue is more serious than we expect, or that we will fail to identify or fully appreciate an existing liability before we become legally responsible to address it. Some of the legal sanctions to which we could become subject could cause the suspension or revocation of a needed permit, or prevent us from or delay us in obtaining or renewing permits to operate or expand our facilities or harm our reputation.

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

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

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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 $28.9 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 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.

        In late June 2009 the U.S. House of Representatives passed HR 2454, The American Clean Energy and Security Act of 2009 (also known as the Waxman/Markey Bill), which is now pending in the U.S. Senate. The bill as passed by the House does not impose any onerous provisions which would adversely affect our facilities, and includes some provisions which might be beneficial to our business of incinerating toxic materials. However, no assurances can be given that the final version of the bill, if enacted by the U.S. Congress and subsequently signed into law by the President, would not include provisions which could cause us to incur additional expenditures.

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 the expansion airspace in our calculations 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 production in that region 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 which we provide to such customers relate to industrial maintenance and production 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.

        Accordingly, declines in the general level of oil and gas production in Western Canada could potentially have in the future significant adverse effects on our total revenues and profitability. Such declines have recently been, and could in the future be, triggered by declines in the commodity prices

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for oil and gas. Such future declines could also be triggered by technological and regulatory changes and other changes in industry and worldwide economic and political conditions.

A significant part of our energy and industrial services business relates to the Alberta oil sands.

        Many of our major customers in the oil and gas industry operating in Western Canada 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 oil 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 decline in the commodity price of oil and gas, potential future changes in environmental restrictions and regulations, and technological and regulatory changes relating to production of oil from the oil sands. Due to the current downturn in worldwide economic conditions and a substantial decline in the commodity price of oil and gas, 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.

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. The oil and gas services industry in Western Canada experienced in the past several years high demand for, and a corresponding shortage of, quality employees. Although the current downturn in the oil and gas industry has increased the pool of quality employees available to meet our customer commitments, any improvement of conditions in the oil and gas industry would likely increase competition for experienced employees.

If we are unable to successfully complete the integration of Eveready's business and operations into our business and operations and realize synergies in the expected time frame, our future results would be adversely affected.

        We substantially increased our energy and industrial services business through our acquisition of Eveready on July 31, 2009. Our integration of Eveready's business and operations into our business and operations has required and will continue to require implementation of appropriate operations, management and financial reporting systems and controls. The integration of Eveready has required and will continue to require the focused attention of our management teams, including a significant commitment of their time and resources. The success of the acquisition will depend, in part, on the combined company's ability to realize the anticipated benefits from combining the respective businesses and operations of Clean Harbors and Eveready 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 and operations of Clean Harbors and Eveready must continue to be successfully combined.

        If the combined company is not able to achieve these objectives, the anticipated benefits to us of the acquisition may not be realized fully or at all or may take longer to realize than expected. It is possible that the integration process could result in the loss of key employees, as well as the disruption of our ongoing businesses, failure to implement the business plan for the combined businesses, unanticipated issues in integrating service offerings, logistics, information, communications and other systems, or other unanticipated issues, expenses and liabilities, any or all of which could adversely affect our ability to maintain relationships with customers and employees and to achieve the anticipated benefits of the acquisition.

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Our acquisition of Eveready may expose us to unknown liabilities.

        Because we acquired all of Eveready's outstanding common shares, our investment in Eveready is subject to all of Eveready's liabilities other than Eveready's debt which we paid either at the time of the acquisition or shortly thereafter upon our issuance of the notes. If there are unknown Eveready obligations, including contingent liabilities, our business could be materially and adversely affected. We may learn additional information about Eveready's business that adversely affects us, such as unknown liabilities or issues relating to internal controls over financial reporting or that could affect our ability to comply with the Sarbanes-Oxley Act or other applicable laws. As a result, our acquisition of Eveready might not be successful.

Risks Relating to Our Level of Debt and the Notes

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

        As of December 31, 2009, after giving effect to our (i) acquisition of Eveready on July 31, 2009, (ii) sale of the notes on August 14, 2009, (iii) repayment between July 24 and August 14, 2009 of substantially all of our and Eveready's then outstanding debt (other than certain capital leases) using a portion of our available cash and the net proceeds from the sale of the notes, and (iv) payment of related fees and expenses, we had outstanding $292.4 million of debt and $88.7 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 new 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.

        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 may 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 may 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 the agreements governing our new revolving credit facility 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 as of December 31, 2009 under our new revolving credit facility up to an additional approximately $31.3 million for purposes of future borrowings and letters of credit. In addition, the

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indenture governing the notes would also allow 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.

Servicing our debt, including the notes, any revolving loans and capital leases, and paying our letter of credit fee obligations, will require a significant amount of cash, and our ability to generate cash depends on many factors beyond our control.

        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 factors, 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 new revolving credit facility or otherwise, in an amount sufficient to enable us to pay our debt and the fee obligations respecting our letters of credit, or to fund our other liquidity needs.

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

        The agreements governing our new revolving credit facility and the indenture relating to the 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 new revolving credit facility requires, and our future credit facilities may require, us to maintain 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

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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.

        The instruments governing certain of our debt, including the indenture governing the notes and our new revolving credit facility, also contain cross-default provisions. Under these provisions, a default under one instrument governing our debt may constitute a default under our other debt instruments that contain cross-default 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.

Risks Relating to Certain Anti-Takeover Provisions

        Sections 8.06 and 7.02 of the Massachusetts Business Corporation Act provide that Massachusetts corporations which are publicly-held must have a staggered board of directors and that written demand by holders of at least 40% of the outstanding shares of each relevant voting group of stockholders is required for stockholders to call a special meeting unless such corporations take certain actions to affirmatively "opt-out" of such requirements. In accordance with these provisions, our By-Laws provide for a staggered Board of Directors which consists of three classes of directors of which one class is elected each year for a three-year term, and require that written application by holders of at least 25% (which is less than the 40% which would otherwise be applicable without such a specific provision in our By-Laws) of our outstanding shares of common stock is required for stockholders to call a special meeting. In addition, our By-Laws prohibit the removal by the stockholders of a director except for cause. These provisions could inhibit a takeover of our company by restricting stockholders action to replace the existing directors or approve other actions which a party seeking to acquire us might propose. A takeover transaction would frequently afford stockholders an opportunity to sell their shares at a premium over then market prices.

ITEM 1B.    UNRESOLVED STAFF COMMENTS

        Not applicable.

ITEM 2.    PROPERTIES

        Our principal executive office is in Norwell, Massachusetts where approximately 104,000 square feet is leased under arrangements expiring in 2022. There are also regional administrative offices in South Carolina and Alberta, Canada. We own or lease property in 36 U.S. states, seven Canadian provinces, Puerto Rico, Bulgaria, China, Mexico, Singapore, Sweden, Thailand and the United Kingdom.

        Our principal property, plant and equipment consist of land, landfill assets and buildings (primarily incinerators, wastewater treatment plants and TSDFs), vehicles and equipment (including environmental remediation equipment). We have 52 active permitted hazardous waste or nonhazardous waste management properties, and 145 additional service centers and satellite or support locations, which occasionally move to other locations as operations and space requirements change. The incinerators, landfills, and TSDFs are our most significant properties and they are included in our Technical Services segment.

        Our properties are sufficient and suitable to our needs. The following tables set forth certain information as of December 31, 2009 regarding our properties. Substantially all of our owned operating properties are mortgaged as collateral for our loans.

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Hazardous Waste Management Properties

        Included in our 52 active hazardous waste management properties are six incineration locations, nine commercial landfills, seven wastewater treatment plants, 20 TSDFs, two solvent recycling facilities and eight facilities which specialize in PCB management, oil and used oil products recycling. Some of our properties offer multiple capabilities. As described below under "Inactive Facilities," and "Asset Held for Sale," we also own 11 closed or inactive facilities and one facility acquired as part of our acquisition of Eveready which we have agreed to divest.

        Incinerators.    We own six operating incineration facilities containing a total of nine incinerators as follows:

        Our incinerators offer a wide range of technological capabilities to customers through this network. Incineration in the United States is provided by a fluidized bed thermal oxidation unit and three solids and liquids-capable incineration facilities. In Canada, we operate two hazardous waste liquid injection incinerators.

        Landfills.    In the United States and Canada, we operate nine commercial landfills as described in the following table, which excludes the Pembina Area Landfill (described below under "Asset Held for Sale") which Eveready owned and operated but which we have agreed to divest:

        Seven of our commercial landfills are designed and permitted for the disposal of hazardous wastes and two landfills are operated for nonhazardous industrial waste disposal and, to a lesser extent, municipal solid waste. In addition to our commercial landfills, we also own and operate two non-commercial landfills that only accept waste from our on-site incinerators. We own all of the landfills with the exception of the landfill in Oklahoma that is leased.

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        Wastewater Treatment Plants.    We operate seven facilities that offer a range of wastewater treatment technologies and customer services, as follows:

        Wastewater treatment consists primarily of three types of services: hazardous wastewater treatment, sludge de-watering or drying, and non-hazardous wastewater treatment.

        Transportation, Storage and Disposal Facilities.    We operate 20 TSDFs in the United States and Canada as follows:

        Our TSDFs facilitate the movement of materials among our network of service centers and treatment and disposal facilities. Transportation may be accomplished by truck, rail, barge or a combination of modes, with our own assets or in conjunction with third-party transporters. Specially designed containment systems, vehicles and other equipment permitted for hazardous and industrial waste transport, together with drivers trained in transportation skills and waste handling procedures, provide for the movement of customer waste streams.

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        PCB Management Facilities and Oil Storage or Recycling Capabilities.    We operate eight facilities specializing in PCB management or providing oil recycling capabilities, as follows:

        These facilities are the most significant properties relating to our Field Services segment.

        Solvent Recycling Operations.    We own two facilities specializing in solvent recovery management in Illinois and Ohio, and also have one solvent recycling operation adjacent to our incineration facility in El Dorado, Arkansas.

Other Facilities and Properties

        Service Centers and Satellite Locations.    We operate 145 additional service centers and satellite or support locations of which 19 are owned and 126 are leased.

        Inactive Facilities.    In addition to the active facilities and properties described above, we own a total of 11 facilities which are now closed or inactive, most of which were acquired in 2002 as part of the CSD assets due to our assumption of the remediation liabilities associated with such properties or our closure of such sites. The principal inactive facilities are a closed incinerator and landfill in Baton Rouge, Louisiana, closed incinerators in Roebuck, South Carolina, Coffeyville, Kansas and Bridgeport, New Jersey, and closed wastewater treatment facilities in Cleveland, Ohio and Plaquemine, Louisiana. Prior to the sale of the CSD assets, Safety-Kleen gave notice to the applicable regulatory agencies of Safety-Kleen's intent to close and stopped accepting wastes at Cleveland in 1990, Baton Rouge in 1997, Roebuck in 1998, Coffeyville in 2000, and Bridgeport in 2001. We gave notice to the regulators and stopped accepting wastes at Plaquemine in 2006.

        Asset Held for Sale.    In connection with our acquisition of Eveready, we agreed with the Canadian Commissioner of Competition to divest Eveready's Pembina Area Landfill, located near Drayton Valley, Alberta, due to its proximity to our existing landfill in the region. The Pembina Area Landfill consists of a landfill facility and an administrative office.

ITEM 3.    LEGAL PROCEEDINGS

        See Note 18, "Commitments and Contingencies," to our consolidated financial statements included in Item 8, "Financial Statements and Supplementary Data," for a description of legal proceedings.

ITEM 4.    RESERVED

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PART II

ITEM 5.    MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Common Stock

        Effective December 15, 2008, our common stock began trading on the New York Stock Exchange under the symbol CLH. Prior to that time, our stock was traded on The NASDAQ Global Select Market under the symbol CLHB. The following table sets forth the high and low sales prices of our common stock for the indicated periods as reported by the New York Stock Exchange and The NASDAQ Global Select Market.

        On February 25, 2010, the closing price of our common stock on the New York Stock Exchange was $56.02 and there were 443 stockholders of record of our common stock, excluding stockholders whose shares were held in nominee, or "street," name. We estimate that approximately 15,000 additional stockholders beneficially held the shares in street name on that date.

        We have never declared nor paid any cash dividends on our common stock, and we do not intend to pay any dividends on our common stock in the foreseeable future. We intend to retain our future earnings, if any, for use in the operation and expansion of our business and payment of our outstanding debt. In addition, our current credit agreement prohibits, and our indenture restricts, us from paying cash dividends on our common stock. See "Liquidity and Capital Resources" under Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations."

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Performance Graph

        The following graph compares the five-year return from investing $100 in each of our common stock, the NASDAQ Market Index, the NYSE Market Index, and an index of environmental services companies (custom peer group) compiled by CoreData. Our common stock commenced trading on the New York Stock Exchange on December 15, 2008, and therefore both the NASDAQ Market Index and the NYSE Market Index are used as comparable indices. The environmental services group used by CoreData includes all companies whose listed line-of-business is SIC Code 4953 (refuse systems), and assumes reinvestment of dividends on the ex-dividend date. An index compares relative performance since a particular starting date. In this instance, the starting date was December 31, 2004, when our common stock closed at $15.09 per share.

COMPARISON OF 5-YEAR CUMULATIVE TOTAL RETURN
AMONG CLEAN HARBORS, INC.,
NASDAQ MARKET INDEX, NYSE MARKET INDEX, AND CUSTOM PEER GROUP

ASSUMES $100 INVESTED ON JAN. 01, 2005
ASSUMES DIVIDEND REINVESTED
FISCAL YEAR ENDING DEC. 31, 2009

Securities Authorized For Issuance Under Equity Compensation Plans

        See Item 12, "Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters," for a description of the securities which are authorized for issuance under our equity compensation plans.

Issuer Purchases of Equity Securities

        During the fiscal quarter ended December 31, 2009, we did not repurchase any of our outstanding common stock or any other securities registered under the Securities Exchange Act of 1934, as amended.

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ITEM 6.    SELECTED FINANCIAL DATA

        The following summary of consolidated financial information has been derived from the audited consolidated financial statements included in Item 8, "Financial Statements and Supplementary Data," of this report and in the annual reports we previously filed with the SEC. This information should be reviewed in conjunction with Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations," and the financial statements and the notes thereto included in Item 8, "Financial Statements and Supplementary Data" of this report.

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(1)

For fiscal year 2006, the provision includes a reversal of $14.1 million of the valuation allowance.

(2)

We issued: (i) 0.4 million shares of common stock in February 2005 upon cashless exercise of previously outstanding warrants; (ii) 1.6 million shares of common stock in October 2005 upon exercise of previously outstanding warrants for an aggregate of $12.5 million; (iii) 2.3 million shares of common stock in December 2005 upon the closing of a public offering for aggregate net proceeds (after deducting the underwriters' discount and offering expenses payable by us) of $60.2 million; (iv) 0.4 million shares of common stock in December 2007 upon exercise of previously outstanding warrants for an aggregate of $1.2 million and conversion of previously outstanding shares of Series B preferred stock; (v) 2.875 million shares of common stock in April 2008 upon the closing of a public offering for aggregate net proceeds (after deducting the underwriters' discount and offering expenses payable by us) of $173.5 million; and (vi) 2.4 million shares of common stock in July 2009 to the former holders of Eveready common shares as partial consideration for our acquisition of Eveready.

(3)

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

We use Adjusted EBITDA to enhance our understanding of our core operating performance, which represents our views concerning our performance in the ordinary, ongoing and customary course of our operations. We historically have found it helpful, and believe that investors have found it helpful, to consider an operating measure that excludes expenses such as debt extinguishment and related costs relating to transactions not reflective of our core operations.

The information about our core operating performance provided by this financial measure is used by our management for a variety of purposes. We regularly communicate Adjusted EBITDA results to our board of directors and discuss with the board our interpretation of such results. We also compare our Adjusted EBITDA performance against internal targets as a key factor in determining cash bonus compensation for executives and other employees, largely because we believe that this measure is indicative of the how the fundamental business is performing and is being managed.

We also provide information relating to our Adjusted EBITDA so that analysts, investors and other interested persons have the same data that we use to assess our core operating performance. We believe that Adjusted EBITDA should be viewed only as a supplement to the GAAP financial information. We also believe, however, that providing this information in addition to, and together with, GAAP financial information permits the foregoing persons to obtain a better understanding of our core operating performance and to evaluate the efficacy of the methodology and information used by management to evaluate and measure such performance on a standalone and a comparative basis.

(4)

Long-term obligations (including current portion) include borrowings under our current and former revolving credit facilities and capital lease obligations.