Item 1.    Business

US Ecology, through our subsidiaries, provides radioactive, hazardous, PCB and non-hazardous industrial waste management and recycling services to commercial and government entities, such as refineries and chemical production facilities, manufacturers, electric utilities, steel mills, medical and academic institutions and waste brokers/aggregators. Headquartered in Boise, Idaho, we are one of the oldest providers of such services in North America. US Ecology and its predecessor companies have been in business for 60 years. We operate within North America and employed 425 people as of December 31, 2012.

Our filings with the SEC are posted on our website at www.usecology.com. The information found on our website is not part of this or any other report we file with or furnish to the SEC. The public can also obtain copies of these filings by visiting the SEC's Public Reference Room at 100 F Street NE, Washington DC 20549, or by calling the SEC at 1-800-SEC-0330 or by accessing the SEC's website at www.sec.gov .

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US Ecology was most recently incorporated as a Delaware corporation in May 1987 as American Ecology Corporation. On February 22, 2010, the Company changed its name from American Ecology Corporation to US Ecology, Inc. Our wholly-owned primary operating subsidiaries are US Ecology Nevada, Inc., a Delaware corporation ("USEN"); US Ecology Washington, Inc., a Delaware corporation ("USEW"); US Ecology Texas, Inc., a Delaware corporation ("USET"); US Ecology Idaho, Inc., a Delaware corporation ("USEI"); US Ecology Michigan, Inc., a Michigan corporation ("USEM"); US Ecology Field Services, Inc., a Delaware corporation ("USEFS"); US Ecology Stablex Holdings, Inc., a Delaware corporation ("USESH"); and Stablex Canada Inc., a Canadian Federal Corporation ("Stablex"). US Ecology Illinois, Inc., a California corporation ("USE"), operates our closed property in Sheffield, Illinois. American Ecology Environmental Services Corporation, a Texas corporation ("AEESC"), operates our closed property in Winona, Texas.

We operate within two business segments: Operating Disposal Facilities and Non-Operating Disposal Facilities. These segments reflect our current operational status and internal reporting structure. Operating Disposal Facilities accept hazardous waste, non-hazardous waste, LARM and LLRW and include our RCRA permitted waste treatment and disposal facilities near Beatty, Nevada; Grand View, Idaho; Detroit, Michigan; and Robstown, Texas, our AEA permitted disposal facility near Richland, Washington and our Blainville, Québec, Canada facility. Our Washington, Idaho and (to a lesser degree) Texas and Nevada facilities also accept certain NORM/NARM waste and LARM. Non-Operating Disposal Facilities include our former disposal facilities in Sheffield, Illinois; Beatty, Nevada; and Bruneau, Idaho and a former hazardous waste processing and deep-well injection operation in Winona, Texas. All other items are included in the segment where they originated. Inter-company transactions have been eliminated from the segment information and are not significant between segments. Financial information with respect to each segment is further discussed in Note 17 to the consolidated financial statements located in Item 8—Financial Statements and Supplementary Data to this Form 10-K.

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The following table summarizes our subsidiaries, locations and services of each segment:

Operating Disposal Facilities

We derive revenue from treating and disposing of hazardous, non-hazardous industrial and radioactive waste in government permitted facilities. We also derive revenue from transportation services generally to get material from the customer location to one of our facilities. Treatment and disposal ("T&D") revenue can be broken down into two categories: "Base Business" and "Event Business." Base Business tends to be waste streams generated through on-going industrial process that is recurring in nature. Event Business is waste generated from a discrete waste clean-up project that is one-time in nature. The duration of Event Business projects can last from a one-week clean-up of a small contaminated site to a multiple year clean-up project.

A significant portion of our disposal revenue is attributable to discrete Event Business projects which vary widely in size, duration and unit pricing. For the year ended December 31, 2012, approximately 35% of our T&D revenue (excluding US Ecology Michigan, Inc., which was acquired on May 31, 2012) was derived from Event Business projects. The one-time nature of Event Business, diverse spectrum of waste types received and widely varying unit pricing necessarily creates variability in revenue and earnings. This variability may be influenced by general economic conditions, funding availability, changes in laws and regulations, government enforcement actions or court orders, public controversies, litigation, weather, real estate redevelopment project timing, government appropriation and funding commitment cycles and other

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factors. The types and amounts of waste received from recurring customers ("Base Business") also vary quarter to quarter, sometimes significantly, but are generally more predictable than Event Business.

Depending on project-specific customer needs and competitive economics, transportation services may be offered at or near our cost to help secure new business. Transportation-related revenue can account for as much as three-fourths (75%) of total project revenue for waste transported by rail from the eastern United States and other locations distant to our Grand View, Idaho or Robstown, Texas facilities.

The types of waste received, also referred to as "service mix," can produce significant quarter-to-quarter and year-to-year variations in revenue, average selling price, gross profit, gross margin, operating profit and net income for both Base Business and Event Business. Event Business contributed approximately 35% and 39% of disposal revenue (excluding transportation and US Ecology Michigan, Inc. revenue) for the years ended December 31, 2012 and 2011, respectively. Base Business represented approximately 65% and 61% of disposal revenue (excluding transportation and US Ecology Michigan, Inc. revenue) for the years ended December 31, 2012 and 2011, respectively. Our strategy is to expand our Base Business while securing both short-term and extended-duration Event Business. When Base Business covers our fixed overhead costs, a significant portion of disposal revenue generated from Event Business is generally realized as operating income and net income. This strategy takes advantage of the favorable operating leverage inherent to the largely fixed-cost nature of the waste disposal business. Contribution margin is influenced by whether the waste is directly disposed ("direct disposal") or requires the application of chemical reagents, absorbents and other additives (variable costs) to treat the waste prior to disposal.

To maximize utilization of our railcar fleet, we occasionally deploy available railcars to transport waste from clean-up sites to disposal facilities operated by other companies. Such transportation services may also be bundled with for-profit logistics and field services support work.

Beatty, Nevada RCRA/TSCA Facility.     Our Beatty, Nevada facility, which began receiving hazardous waste in 1970, is located in the Amargosa Desert approximately 120 miles northwest of Las Vegas, Nevada and approximately 30 miles east of Death Valley, California. USEN subleases 80 acres from the State of Nevada located within a 400 acre buffer zone leased by the State of Nevada from the federal government. The Company believes this dedicated buffer zone is a viable location for expansion to accommodate future disposal operations. In April 2007, we renewed our lease with the State of Nevada as a year-to-year periodic tenancy until (i) that area reaches full capacity and can no longer accept waste (estimated life using 2012 volume of 6-7 years); (ii) the lease is terminated by us at our option; or (iii) the State terminates the lease due to our breach of the lease terms. The facility is a hazardous waste treatment, storage and disposal facility permitted under Subtitle C of RCRA and TSCA and is permitted to treat and dispose of RCRA, TSCA and certain NRC-exempt radioactive waste. The facility was the first hazardous waste site in the nation to receive authorization to receive TSCA regulated materials, and remains a national outlet for TSCA regulated waste. The facility provides full RCRA treatment and solidification services for industrial and government customers. The facility also provides chemical oxidation for organic contaminated wastes and oil refinery catalysts, providing a cost-effective alternative to incineration. Certain low-activity radioactive wastes which are exempt from NRC regulation may also be accepted for disposal. The facility is regulated under permits issued by the Nevada Department of Environmental Protection and the USEPA. The State of Nevada assesses disposal fees to fund a dedicated trust account to pay for closure and post-closure costs.

Richland, Washington LLRW Facility.     Our Richland, Washington LLRW facility has been in operation since 1965 and is located on 100 acres of land leased by the State of Washington on the U.S. Department of Energy Hanford Reservation approximately 35 miles west of Richland, Washington. USEW subleases this property from the State of Washington. The lease between the State of Washington and the federal government expires in 2063. We renewed our sublease with the State in 2005 for ten years with four ten-year renewal options. The facility is a low-level radioactive waste disposal facility serving the Northwest and Rocky Mountain Compacts. The facility accepts Class A, B, and C commercial low-level radioactive

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waste from within the Northwest and Rocky Mountain Compacts, and NORM/NARM waste including radium sources produced by customers nationwide. The facility is one of only three full-service Class A, B, and C disposal facilities in the nation. The facility's personnel have extensive experience safely managing reactor internals and other high dose rate radioactive waste through the use of shielding and remote handling devices. The facility is licensed by the Washington Department of Health for health and safety purposes. The WUTC sets disposal rates for LLRW. Rates are set at an amount sufficient to cover operating costs and provide us with a reasonable profit. The current rate agreement with the WUTC is effective from January 1, 2008 to January 1, 2014. The WUTC process to establish rates for the succeeding rate period is underway. The State assesses user fees for local economic development, state regulatory agency expenses and a dedicated trust account to pay for long-term care after the facility closes. The State maintains separate dedicated trust funds for future closure and post-closure costs.

Robstown, Texas RCRA Facility.     Our Robstown, Texas facility began operations in 1973. It is located on 240 acres owned by the Company approximately 10 miles west of Corpus Christi, Texas. We own 200 acres of adjacent land for future expansion. We also own 174 acres of land five miles from the facility adjacent to a rail line where we have operated a rail transfer station since 2006. The facility is a hazardous waste treatment, storage and disposal facility permitted under Subtitle C of RCRA. The facility is permitted to store PCB waste for off-site shipment and treat and dispose of RCRA, and PCB remediation waste. Specializing in serving the petrochemical industry of the Gulf Coast region, the facility provides stabilization, solidification, chemical oxidation, and waste brokerage services for its industrial and government customers. A low temperature thermal desorption unit was added in 2008 for recycling of petroleum wastes and refinery cracking catalysts. This facility provides a recycling alternative for oil-bearing hazardous waste from petroleum refineries and produces recycled products for energy recovery, re-refining, and metals recovery. The facility also accepts low-concentration NRC-exempt radioactive waste which is also exempted under Texas regulations with concurrence from the Texas Commission on Environmental Quality.

Grand View, Idaho RCRA/TSCA Facility.     Our Grand View, Idaho facility was purchased in 2001. It is located on 1,252 acres of Company-owned land approximately 60 miles southeast of Boise, Idaho in the Owyhee Desert. We own an additional 159 acres approximately two miles east of the facility, which is used as a clay source for site operations (liner construction and reagent). We also own 189 acres where our rail transfer station is located approximately 30 miles northeast of the disposal facility. This site has two enclosed rail-to-truck waste transfer facilities located adjacent to the main line of the Union Pacific Railroad. The facility is a hazardous waste treatment, storage and disposal facility permitted under Subtitle C of RCRA and the TSCA. The facility is permitted to treat and dispose of RCRA and TSCA wastes, as well as a wide range of low-activity radioactive wastes and NORM/NARM, Technologically Enhanced NORM (TENORM) and other wastes exempted from federal regulation by the NRC. The facility provides treatment and disposal services to both government and private industry waste generators, and is a major recipient of U.S. Army Corps of Engineers FUSRAP waste. In 2004, the facility's permit was modified to allow receipt of NRC-exempt low activity fission and activation products. In 2008 this list was expanded to include special nuclear materials exempt from NRC regulation. The facility also serves the steel industry and a wide range of broker-served and other hazardous waste producers.

Detroit, Michigan RCRA Facility.     Our Detroit, Michigan facility, acquired in 2012, has been serving the mid-western and eastern U.S. industrial markets for nearly 40 years. The facility is located on 6 acres of Company-owned land in a heavily-industrialized section of Detroit, Michigan. The facility is permitted to accept non-hazardous and hazardous materials and to treat non-hazardous solids and non-hazardous waste water regulated under RCRA. The facility is regulated under permits issued by the Michigan Department of Environmental Quality and the Detroit Sewer and Water Department.

Blainville, Québec, Canada Facility ("Stablex").     Our Stablex facility, acquired in October 2010, has been in operation since 1983 and is located approximately 30 miles northwest of Montreal, Québec, Canada. The

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facility owns and operates a treatment facility located on 25 acres adjacent to a 325 acre disposal site that is leased from the Province of Québec. The lease with the Province expires in 2018 and has one five-year renewal term. The facility uses the "Stablex" process to treat and stabilize inorganic hazardous wastes and contaminated soils to produce a non-leachable concrete-like material. We accept a wide range of inorganic wastes and contaminated soils at the facility and specialize in processing hard-to-treat materials, such as cyanides, mercury compounds, strong acids/oxidizers, lab packs, contaminated debris and batteries. The facility is permitted by the Canadian Ministry of Environment and is authorized under the Environmental Quality Act by Order-in-Council for use exclusively for products treated and disposed by Stablex as the lessee. The facility is a truck and rail-served hazardous waste treatment storage and disposal facility. The Province assesses fees to fund a dedicated government trust account to pay for post-closure costs at the disposal site. Stablex is responsible for closing each landfill prior to final closure of the facility. The site is permitted to accept up to 875,000 metric tons (962,500 U.S. tons) over the five-year permit period. Of this amount, up to 350,000 metric tons (385,000 U.S. tons) can be accepted as soil. While there are no specific restrictions on waste soils received from the U.S., non-soil waste received from the U.S. is limited to 350,000 metric tons (385,000 U.S. tons) over the five-year permit period.

Non-Operating Disposal Facilities

Bruneau, Idaho RCRA Site.     This remote 83 acre desert site, acquired in conjunction with the Grand View, Idaho disposal operation in 2001, was closed by the prior owner under an approved RCRA plan. Post-closure monitoring is expected to continue for approximately 17 years, or 2029, in accordance with permit and regulatory requirements.

Sheffield, Illinois RCRA Site.     We previously operated two hazardous waste disposal areas next to the Sheffield LLRW disposal area. The first opened in 1968 and ceased operations in 1974. The second accepted waste from 1974 through 1983. We expect to perform groundwater remediation and monitoring at the site for approximately 13 more years through 2025.

Winona, Texas Site.     From 1980 to 1994, Gibraltar Chemical Resources operated the Winona hazardous waste processing and deep well facility. In 1994, we purchased the facility. Solvent recovery, deep well injection and waste brokering operations were conducted on a nine acre site until 1997 when we ceased operations. We are proceeding under a post-closure order with the State of Texas and expect to perform groundwater remediation and monitoring at the site for approximately 27 more years through 2039. We own a 297 acre buffer zone adjacent to the permitted area.

INDUSTRY

During the 1970s and 1980s, waste services industry growth in the United States was driven by new environmental laws and actions by federal and state agencies to regulate existing hazardous waste management facilities and direct the clean-up of contaminated sites under the federal Superfund law. By the early 1990s, excess hazardous waste management capacity had been constructed by the industry. Over this same period, to better manage risk and reduce expenses, many waste generators instituted industrial process changes and other methods to reduce waste production. Waste volumes shipped for disposal from Superfund and other properties also diminished as contaminated sites were cleaned up. These factors led to highly competitive market conditions that still apply today.

We believe that a baseline demand for hazardous waste services will continue into the future with fluctuations driven by general and industry-specific economic conditions, identification of new clean-up needs, clean-up project schedules, funding availability and other public policy decisions. We further believe that the ability to deliver specialized niche services while aggressively competing for large volume clean-up projects and non-niche commodity business opportunities differentiates successful from less successful companies. We seek to control variable costs, expand service lines, increase waste throughput efficiency, employ innovative treatment techniques, build market share and increase profitability. Past initiatives that have successfully contributed to our increased operating income include, but are not limited to:

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acquiring our Grand View, Idaho treatment and disposal facility and rail transfer station in 2001;

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expanding our radioactive material and hazardous waste permits to manage additional types of waste;



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expanding our rail transportation services and logistical capabilities through a fleet of Company-owned and leased railcars;



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adding track, a second main line switch and constructing a second rail-to-truck transload building in Idaho;



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acquiring property and developing a rail transfer station in Texas;



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constructing new, high-capacity waste treatment and storage buildings in Texas and Nevada;



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expanding our organic chemical waste treatment laboratory in Texas to improve treatment "recipes" and reduce costs at all three of our RCRA facilities;



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establishing a thermal recycling service at our Robstown, Texas site which allows the facility to accept recyclable hydrocarbon-oil-bearing hazardous waste and cracking catalyst from petroleum refining;



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constructing a specialized handling system for packaging thermally treated cracking catalyst at our Robstown, Texas facility in 2011;



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acquiring our Blainville, Québec, Canada treatment and disposal facility and rail transfer station in 2010; and



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acquiring our Detroit, Michigan chemical and industrial byproducts treatment and reuse facility in 2012.

Our Richland, Washington disposal facility, serving the Northwest and Rocky Mountain LLRW Compacts, is one of three operating Compact disposal facilities in the nation. While our Washington disposal facility has substantial unused capacity, it can only accept LLRW from the 11 western states comprising the two Compacts served. The Barnwell, South Carolina site, operated by Energy Solutions, Inc. ("Energy Solutions"), exclusively serves the three-state Atlantic Compact. A third LLRW disposal facility, licensed by Waste Control Specialists, LLC and located near Andrews, Texas serves the two-state Texas Compact and approved out-of-compact generators. Class A LLRW from states outside the Northwest Compact region may also be disposed at a non-compact, commercial disposal site in Clive, Utah, also operated by Energy Solutions.

Pricing at AEA licensed LLRW disposal facilities heightened demand for more cost-effective disposal options for soil, debris, consumer products, industrial wastes and other materials containing LARM, including "mixed wastes," exhibiting both hazardous and radioactive properties. In addition to commercial demand, a substantial amount of LARM is generated by government clean-up projects. The NRC, USEPA and USACE have authorized the use of hazardous waste disposal facilities to dispose of certain LARM, encouraging expansion of this compliant, cost-effective alternative. Our Grand View, Idaho RCRA hazardous waste facility has significantly increased waste throughput based on a series of permit modifications and project-specific approvals allowing expanded LARM acceptance. Our Robstown, Texas and Beatty, Nevada disposal facilities are also permitted to accept LARM on a more limited basis. We believe we are well positioned to continue growing our LARM business based on our:

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longstanding disposal industry reputation and commercial branding dating from the early 1960s;



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environmental conditions and containment designs favoring permanent waste isolation;



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existing permits, including recent modifications allowing additional waste types;



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safety and regulatory compliance record;



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decades of experience safely handling radioactive materials at multiple facilities;

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high volume waste throughput capabilities, including rail transportation and field services support;



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competitive pricing; and



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regulatory policies and precedents allowing disposal of LLRW at authorized hazardous waste disposal facilities.

Permits, Licenses and Regulatory Requirements

Obtaining authorization to construct and operate new radioactive or hazardous waste facilities is a lengthy and complex process. We believe we have demonstrated significant expertise in this area over multiple decades. We also believe we possess all permits, licenses and regulatory approvals required to maintain regulatory compliance and operate our facilities and have the specialized expertise required to obtain additional approvals to continue growing our business in the future.

We incur costs and make capital investments to comply with environmental regulations. These regulations require that we operate our facilities in accordance with permit-specific requirements. Our Idaho, Texas and Michigan facilities are also required to provide financial assurance for closure and post-closure obligations should our facilities cease operations. Our Blainville, Québec operation is required to post commercial surety bonds to cover closure obligations. Both human resource and capital investments are required to maintain compliance with these requirements.

United States Hazardous Waste Regulation

Our hazardous, industrial, non-hazardous and radioactive materials business is subject to extensive federal and state environmental, health, safety, and transportation laws, regulations, permits and licenses. Local government controls may also apply. The responsible government regulatory agencies regularly inspect our operations to monitor compliance. They have authority to enforce compliance through the suspension or revocation of operating licenses and permits and the imposition of civil or criminal penalties in case of violations. We believe that these laws and regulations, as well as the specialized services we provide, contribute to demand and create barriers to new competitors entering the markets we serve.

RCRA provides a comprehensive framework for regulating hazardous waste transportation, treatment, storage and disposal. RCRA regulation is the responsibility of the USEPA, which may delegate authority to state agencies. Chemical compounds and residues derived from USEPA-listed industrial processes are subject to RCRA standards unless they are delisted through rulemaking such as the steel mill waste treatment process employed at our Grand View, Idaho facility. RCRA liability may be imposed for improper waste management or failure to take corrective action for releases of hazardous substances. To the extent wastes are recycled or beneficially reused, regulatory controls and permitting requirements under RCRA diminish. LARM and NORM/NARM may also be managed to varying degrees under RCRA permits, as is authorized for our facilities in Grand View, Idaho; Beatty, Nevada; and Robstown, Texas.

CERCLA and its amendments impose strict, joint and several liability on owners or operators of facilities where a release of hazardous substances has occurred, on parties who generated hazardous substances released at such facilities and on parties who arranged for the transportation of hazardous substances. Liability under CERCLA may be imposed if releases of hazardous substances occur at treatment, storage or disposal sites. Since waste generators, transporters and those who arrange transportation are subject to the same liabilities, we believe they are motivated to minimize the number of disposal sites used. In addition, hazardous waste generated during the remediation of CERCLA cleanup projects and transferred offsite must be managed by a treatment and disposal facility authorized by EPA to manage CERCLA waste. Our Grand View, Idaho; Beatty, Nevada; Robstown, Texas; and Detroit, Michigan facilities have this authorization.

TSCA regulates the treatment, storage and disposal of PCBs. U.S. regulation and licensing of PCB wastes is the responsibility of the USEPA. Our Grand View, Idaho and Beatty, Nevada disposal facilities have

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TSCA treatment, storage and disposal permits. Our Robstown, Texas facility has a TSCA storage permit and may dispose of PCB-contaminated waste in limited concentrations not requiring a TSCA disposal permit.

The AEA, as amended, assigns the NRC regulatory authority over receipt, possession, use and transfer of certain radioactive materials, including disposal. The NRC has adopted regulations for licensing commercial LLRW disposal and has delegated regulatory authority to certain states including Washington, where our Richland facility is located. The NRC and U.S. Department of Transportation regulate the transport of radioactive materials. Shippers must comply with both the general requirements for hazardous materials transportation and specific requirements for transporting radioactive materials.

The Energy Policy Act of 2005 amended the AEA to classify discrete (i.e. concentrated versus diffuse) NORM/NARM as byproduct material. The law does not apply to interstate Compacts ratified by Congress pursuant to the LLRW Policy Act.

Canadian Hazardous Waste Regulation

The Canadian federal government regulates issues of national scope where activities cross provincial boundaries and affect Canada's relations with other nations. The Provinces retain control over environmental matters within their boundaries including primary responsibility for regulation and management of hazardous waste.

The main federal laws governing hazardous waste management are the CEPA and the Transportation of Dangerous Goods Act. Environment Canada is the federal agency with responsibility for environmental matters. CEPA charges Environment Canada and Health Canada with the protection of human health and the environment and seeks to control the production, importation and use of substances in Canada and their impact on the environment. The Export and Import of Hazardous Waste Regulations under CEPA govern trans-border movement of hazardous waste and hazardous recyclable materials. These regulations require that anyone proposing to export or import hazardous waste or hazardous recyclable materials or transport them through Canada notify the Minister of the Environment and obtain a permit to do so.

Our Stablex facility operates in the Province of Québec and is subject to the QEQA. This Act, independently developed by the Province, regulates the generation, characterization, transport, treatment and disposal of hazardous wastes. QEQA also provides for the establishment of waste management facilities which are controlled by the provincial statutes and regulations governing releases to air, groundwater and surface water.

Under QEQA, waste can be defined as hazardous based on origin or characteristic in a manner that is very similar to regulations in effect in the United States. A major difference between the United States regulatory regime and that in Canada relates to ownership and liability. Under Canadian federal regulation, ownership changes when waste is transferred to a properly permitted third-party carrier and subsequently to an approved treatment and disposal facility. As a result, the generator is no longer liable for proper handling, treatment or disposal. In the United States, joint and several liability is retained by the waste generator as well as the transporter and the treatment and disposal facility.

Waste transporters require a permit to operate under Québec's regulations and are also subject to the requirements of the Federal Transportation of Dangerous Goods law which requires reporting of quantities and disposition of materials shipped.

Insurance, Financial Assurance and Risk Management

We carry a broad range of insurance coverage, including general liability, automobile liability, real and personal property, workers compensation, directors and officers liability, environmental impairment liability and other coverage customary to the industry. We do not expect the impact of any known casualty,

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property, environmental or other contingency to be material to our financial condition, results of operations or cash flows.

As noted above, applicable regulations require financial assurance to cover the cost of final closure and post-closure obligations at certain of our operating and non-operating disposal facilities. Acceptable forms of financial assurance include third-party standby letters of credit, surety bonds and insurance. Alternatively, we may be required to collect fees from waste generators to fund dedicated, state-controlled escrow or trust accounts during the operating life of the facility. Through December 31, 2012, we have met our financial assurance requirements through insurance, surety bonds, standby letters of credit and self-funded restricted trusts.

Insurance policies covering U.S. closure and post-closure obligations expire in December 2013.We are required by our insurer to maintain collateral at agreed upon levels to support our aggregate financial assurance insurance policies for our operating sites through the policy term. While we expect to timely renew these policies as we have in the past, if we are unable to obtain adequate closure, post-closure or environmental insurance, any partial or completely uninsured claim against us, if successful, could have a material adverse effect on our financial condition, results of operations and cash flows. Failure to maintain adequate financial assurance could also result in regulatory action including early closure of facilities. For our non-operating facilities, we established an interest bearing trust account to guarantee our post-closure liability, subject to regulatory approval. As of December 31, 2012, we have provided collateral of $4.1 million in funded trust agreements, issued $4.0 million in letters of credit for financial assurance and have insurance policies of approximately $43.0 million for closure and post-closure obligations. Financial assurance, premium and collateral cost requirements increases have an adverse impact on our results of operations.

We maintain a surety bond for closure costs associated with the Stablex facility. Our lease agreement with the Province of Québec requires that the surety bond be maintained for 25 years after the lease expires. At December 31, 2012 we had $897,000 in commercial surety bonds dedicated for closure obligations.

Primary casualty insurance programs generally do not cover accidental environmental contamination losses. To provide insurance protection for potential claims, we maintain pollution legal liability insurance and professional environmental consultant's liability insurance for non-nuclear occurrences. For nuclear liability coverage, we maintain Facility Form and Workers' Form nuclear liability insurance provided under the federal Price Anderson Act. This insurance covers the operations of our facilities, suppliers and transporters. We purchase primary property, casualty and excess liability policies through traditional third-party insurance carriers.

Significant Customers

We dispose of LARM and hazardous waste under a contract with the USACE. We also arrange transportation of waste to our disposal facilities for both government and industry customers which contributes significant revenue. USACE accounted for 6%, 7% and 17% of our revenue in 2012, 2011 and 2010, respectively. No other customer accounted for more than 10% of our revenue for 2012, 2011 or 2010.

Markets

Disposal Services.     Waste containing heavy metals or hazardous waste that does not require treatment prior to disposal is generally subject to highly competitive pricing. These commoditized services are also sensitive to transportation distance and related costs. Waste transported by rail is typically less expensive, on a per-mile basis, than waste transported by truck. Hazardous waste containing organic chemical compounds or mercury and LARM are less commoditized services.

Our Robstown, Texas facility is well positioned to serve refineries, chemical production plants and other industries concentrated near the Texas Gulf coast. The facility also accepts certain NORM and LARM. In

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2006, we constructed a rail transfer station approximately five miles from this facility that extends the facility's geographic reach. In 2007, our Texas facility expanded its laboratory to include analysis of organic chemical compounds, which are contained in many of the wastes produced by customers. In June 2008, we began operating a high-throughput thermal desorption unit at the facility which allows us to accept recyclable, hydrocarbon-based materials.

Our Beatty, Nevada facility primarily competes for business in California, Arizona, Utah and Nevada. Due to the site's superior geologic and climate conditions in the Amargosa Desert, the Beatty, Nevada facility also competes for wastes from more distant locations. The Beatty, Nevada facility competes over a larger geographic area for PCB waste due to the more limited number of TSCA disposal facilities nationwide. The facility also accepts small amounts of NORM.

Our Grand View, Idaho facility accepts waste from across the U.S. and, on a more limited basis, Canada shipped through our rail transfer station located adjacent to a main east-west rail line. Waste throughput has been significantly enhanced by rail track expansions in 2006, 2008 and 2011 and the construction of a second rail-to-truck indoor transfer building in 2006. The Grand View facility's primary markets are RCRA, LARM and mixed waste clean-up projects, and brokered waste. Permit modifications have expanded LARM services. The infrastructure at our Grand View, Idaho facility is capable of handling large volumes of waste from large clean-up projects. For example, between 2005 and 2009 the facility disposed of approximately 1.3 million tons of waste shipped from a Honeywell project in Jersey City, New Jersey. We also accept significant volumes from the USACE. In 2010, we entered into a new contract with the USACE, on essentially the same terms and conditions as the previous contract, which expires in 2013. The USACE may extend the contract to 2015 at their sole option. Multi-year USACE projects initiated before the expiration date may continue for five years beyond 2013, or 2015 if the option term is exercised under the same terms. Based on public statements, we believe that the USACE expects to contract for disposal of FUSRAP wastes through approximately 2033.

To meet USEPA land disposal restrictions ("LDRs"), waste stabilization, encapsulation, chemical oxidation and other treatment technologies are used at our Grand View, Idaho; Beatty, Nevada; and Robstown, Texas facilities. These capabilities allow all three sites to manage a much broader spectrum of wastes than if LDR treatment was not offered. Our Robstown, Texas facility also offers thermal desorption treatment and recycling services.

Our Blainville, Québec, Canada facility, Stablex, primarily accepts waste from the Eastern Canadian and Northeastern U.S. industrial markets. The Stablex facility accepts inorganic and certain organic hazardous waste in liquid, semi-solid (sludge) or solid form and treats the waste using a cementitious stabilization process to immobilize the hazardous constituents rendering the homogenized waste product non-hazardous in accordance with Québec treatment regulations. The waste is then disposed in a secure disposal cell. Stablex accepts waste delivered by truck or by rail.

Our Richland, Washington facility serves LLRW producers in the eight states of the Northwest Compact. The three Rocky Mountain Compact states may also use our facility. Since we are a designated monopoly LLRW service provider in the Northwest Compact, the State of Washington approves our disposal rates. Since NORM/NARM is not subject to Compact restrictions, we may accept this waste from all 50 states. Rate regulation does not apply to NORM/NARM pricing since monopoly conditions do not apply.

Our Detroit, Michigan facility primarily competes for business in the Midwestern U.S. and Ontario, Canada markets. The facility also competes for certain high concentration liquid caustic acid wastes in the Northeastern and Southeastern United States. The primary industries served include automotive and related suppliers and other industrial facilities.

Geographical Information.     For the year ended December 31, 2012, we derived $130.9 million or 77% of our revenue in the United States and $38.2 million or 23% of our revenue in Canada. For the year ended December 31, 2011, we derived $118.4 million or 76% of our revenue in the United States and

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$36.5 million or 24% of our revenue in Canada. For the year ended December 31, 2010, we derived $99.1 million or 95% of our revenue in the United States and $5.7 million or 5% of our revenue in Canada.

Competition

We compete with large and small companies in each of the commercial markets we serve. While niche services apply, the radioactive, hazardous and non-hazardous industrial waste management industry is generally very competitive. We believe that our primary hazardous waste and PCB disposal competitors are Clean Harbors, Inc.; The Environmental Quality Company; Heritage Environmental; Waste Control Specialists, LLC; and Waste Management, Inc. We believe that our primary radioactive material disposal competitors are Energy Solutions, Inc. and Waste Control Specialists, LLC. The principal competitive factors applicable to both of these business areas are:

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price;



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specialized permits and "niche" service offerings;



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customer service;



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operational efficiency and technical expertise;



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regulatory compliance and worker safety;



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industry reputation and brand name recognition;



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transportation distance; and



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State or Province and local community support.

We believe that we are competitive in all markets we serve and that we offer a unique mix of services, including niche technologies and services that favorably distinguish us from competitors. We also believe that our strong brand name recognition from six decades of experience, compliance and safety record, customer service reputation and positive relations with regulators and local communities enhance our competitive position. Advantages exist for competitors that have technology, permits or equipment to handle a broader range of waste, that operate in jurisdictions imposing lower disposal fees and/or are located closer to where wastes are generated.

We do not compete with companies seeking federal government contracts to manage or operate radioactive waste treatment and disposal facilities owned by the U.S. Department of Energy ("USDOE"). We accept minor amounts of remediation waste from USDOE facilities at our disposal facilities from time to time; however, this is not a material part of our business.

Seasonal Effects

Seasonal fluctuations due to weather and budgetary cycles can influence the timing of customer spending for our services. Typically, in the first quarter of each calendar year there is less demand for Event Business due to reduced construction activities related to weather. While large, multi-year clean-up projects may continue in winter months, the pace of waste shipments may be slower, or stop temporarily, due to weather. Market conditions and federal funding decisions generally have a greater influence on the business than seasonality.

Personnel

On December 31, 2012, we had 425 employees, of which 11 were members of the Paper, Allied-Industrial Chemical & Energy Workers International Union, AFL-CIO and CLC (PACE) at our Richland, Washington facility and 97 were members of the Communications, Energy and Paperworkers Union of Canada at our Blainville, Québec, Canada facility.

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Table of Contents

Jeffrey R. Feeler was appointed President and Chief Operating Officer in October 2012. Mr. Feeler previously served as the Company's Vice President and Chief Financial Officer from May 2007 to October 2012. He joined US Ecology in 2006 as Vice President, Controller, Chief Accounting Officer, Treasurer and Secretary. He previously held financial and accounting management positions with MWI Veterinary Supply, Inc. (2005-2006), Albertson's, Inc. (2003-2005) and Hewlett-Packard Company (2002-2003). From 1993 to 2002, he held various accounting and auditing positions for PricewaterhouseCoopers LLP. Mr. Feeler is a Certified Public Accountant and holds a BBA of Accounting and a BBA of Finance from Boise State University.

Simon G. Bell was appointed Vice President of Operations in August of 2007 and is responsible for managing both operating and closed facilities. From 2005 to August 2007, he was Vice President of Hazardous Waste Operations. From 2002 to 2005, he was our Idaho facility General Manager and Environmental Manager. His 20 years of industry experience includes service as general manager of a competitor disposal facility and mining industry experience in Idaho, Nevada and South Dakota. He holds a BS in Geology from Colorado State University.

John M. Cooper joined us in July 2002 and is Vice President and Chief Information Officer. Previously, he served as Vice President, Information Systems for BMC West Corporation and was Director of Business Development for the High Tech Industry at Oracle Corporation. Mr. Cooper offers more than 20 years of computer industry experience. He holds a BS in Physics from Utah State University.

Eric L. Gerratt was appointed Vice President, Chief Financial Officer, Treasurer and Chief Accounting Officer in October 2012. He joined US Ecology in August 2007 as Vice President and Controller. He previously held various financial and accounting management positions at SUPERVALU, Inc. (2006-2007) and Albertson's, Inc. (2003-2006). From 1997 to 2003, he held various accounting and auditing positions for PricewaterhouseCoopers LLP. Mr. Gerratt is a Certified Public Accountant and holds a BS in Accounting from the University of Idaho.

Steven D. Welling was appointed Senior Vice President, Sales and Marketing in January 2010. He joined US Ecology in 2001 through the Envirosafe Services of Idaho (now US Ecology Idaho) acquisition. He previously served as National Accounts Manager for Envirosource Technologies and Western Sales Manager for Envirosafe Services of Idaho and before that managed new market development and sales for a national bulk chemical transportation company. Mr. Welling holds a BS from California State University-Stanislaus.