Clean Harbors Announces $500 Million Senior Notes Offering

Clean Harbors, Inc. ("Clean Harbors" or the "Company") (NYSE: CLH) announced today that it is commencing a private offering of $500 million of senior notes (the "notes"). Clean Harbors expects the notes to mature in 2031. It is anticipated that the net proceeds from this offering and a $114.0 million loan under Clean Harbors' existing revolving credit facility, together with cash on hand, will be used to repay the $614.0 million aggregate principal amount of senior secured term loans due in 2024 which are now outstanding under the Company's term loan credit facility and to pay fees and expenses in connection with the offering of the notes and accrued interest in connection with such repayment of senior secured term loans.

The notes will be offered and sold to persons reasonably believed to be qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended (the "Securities Act"), and outside the United States pursuant to Regulation S under the Securities Act. This press release does not constitute an offer to sell or the solicitation of an offer to buy any of the notes, nor shall there be any sale of notes in any jurisdiction in which such offer, solicitation or sale would be unlawful. The notes will not be registered under the Securities Act or the securities laws of any other jurisdiction and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements.

About Clean Harbors

Clean Harbors (NYSE: CLH) is North America's leading provider of environmental and industrial services. The Company serves a diverse customer base, including a majority of Fortune 500 companies. Its customer base spans a number of industries, including chemical, energy and manufacturing, as well as numerous government agencies. These customers rely on Clean Harbors to deliver a broad range of services such as end-to-end hazardous waste management, emergency spill response, industrial cleaning and maintenance, and recycling services. Through its Safety-Kleen subsidiary, Clean Harbors also is North America's largest re-refiner and recycler of used oil and a leading provider of parts washers and environmental services to commercial, industrial and automotive customers. Founded in 1980 and based in Massachusetts, Clean Harbors operates throughout the United States, Canada, Mexico, Puerto Rico and India.

Safe Harbor Statement

Any statements contained herein that are not historical facts are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are generally identifiable by use of the words "believes," "expects," "intends," "anticipates," "plans to," "seeks," "should," "estimates," "projects," "may," "likely," or similar expressions. Such statements may include, but are not limited to, statements about future financial and operating results, the Company's plans, objectives, expectations and intentions and other statements that are not historical facts. Such statements are based upon the beliefs and expectations of Clean Harbors' management as of this date only and are subject to certain risks and uncertainties that could cause actual results to differ materially, including, without limitation, those items identified as "risk factors" in Clean Harbors' most recently filed Form 10-K and Form 10-Q. Forward-looking statements are neither historical facts nor assurances of future performance. Therefore, readers are cautioned not to place undue reliance on these forward-looking statements. Clean Harbors undertakes no obligation to revise or publicly release the results of any revision to these forward-looking statements other than through its various filings with the Securities and Exchange Commission.