BASIS OF PRESENTATION

9 Months Ended

Sep. 30, 2013

Organization, Consolidation and Presentation of Financial Statements [Abstract]

BASIS OF PRESENTATION

BASIS OF PRESENTATION

The accompanying consolidated interim financial statements are unaudited and include the accounts of Clean Harbors, Inc. and its subsidiaries (collectively, “Clean Harbors,” the “Company” or "we") and have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”) and, in the opinion of management, include all adjustments which are of a normal recurring nature, necessary for a fair presentation of the financial position, results of operations, and cash flows for the periods presented. The results for interim periods are not necessarily indicative of results for the entire year or any other interim periods. The financial statements presented herein should be read in connection with the financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2012.

During the first quarter of 2013, the Company adjusted its operating segments to integrate the business activities of Safety-Kleen, Inc. and its subsidiaries (collectively, “Safety-Kleen”) acquired in December 2012, and to incorporate other changes made in 2013 to the manner in which the Company manages its business, makes operating decisions and assesses its performance. Under the new structure, the Company's operations are managed in five reportable segments: Technical Services, Oil Re-refining and Recycling, SK Environmental Services, Industrial and Field Services, and Oil and Gas Field Services. The prior year segment information has been recast to conform to the current year presentation. See Note 17, “Segment Reporting.”