Clean Harbors Announces U.S. Bankruptcy Court Approval of Safety-Kleen Bidding Procedures.

Business Editors

BRAINTREE, Mass.--(BUSINESS WIRE)--March 11, 2002

Clean Harbors, Inc. (Nasdaq: CLHB) today announced that the U.S. Bankruptcy Court supervising the Chapter 11 proceedings of Safety-Kleen, Inc. has ruled favorably on Safety-Kleen's motion to sell the assets of its Chemical Services Division (CSD), subject to an auction scheduled to be conducted June 3, 2002. All bidders must have financing in place by May 30, 2002.

The ruling, issued late Friday by the U.S. Bankruptcy Court for the District of Delaware, followed last month's signing of a definitive agreement under which Clean Harbors will acquire Safety-Kleen's CSD for $46.3 million in cash and certain environmental liabilities valued at approximately $265 million.

"With more than two decades of experience in the hazardous waste business, Clean Harbors is in the best position to successfully own and manage these assets," said Alan S. McKim, Clean Harbors' Chairman and CEO. "As we have said, this transaction is consistent with each of the elements of our growth strategy -- geographic expansion, the introduction of new products and services, and increased penetration of existing markets. We also have the most technologically advanced IT systems in the industry, systems that we believe will enable us to achieve substantial cost efficiencies and dramatic gains in productivity."

"We look forward to finalizing the necessary approvals and other closing conditions in the coming months, and to completing the transaction during the third quarter of 2002," McKim concluded.

About Safety-Kleen Corp.

Based in Columbia, South Carolina, Safety-Kleen Corp. is the largest industrial and hazardous waste management company in North America, serving more than 400,000 customers in the United States, Canada, Mexico and Puerto Rico.

About Clean Harbors, Inc.

Clean Harbors, Inc. through its subsidiaries provides a wide range of environmental and waste management services to a diversified customer base including a majority of the Fortune 500 companies, thousands of smaller private entities and numerous governmental agencies. Within its national footprint, the Company currently has service and sales offices located in 27 states and Puerto Rico, and operates 11 waste management facilities strategically located throughout the country. For more information, visit our Web site at www.cleanharbors.com.

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, and involve risks and uncertainties. These forward-looking statements 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 these forward-looking statements. The specific risks attendant to the definitive agreement, among others, include the contingencies that ultimate approval of the transaction rests with the Bankruptcy Court for the District of Delaware, the ability of Clean Harbors to obtain financing, along with other regulatory approvals and satisfactory completion of its due diligence efforts. Any one of these factors or other unknown risks may alter, delay or result in the transaction not being consummated as intended. Readers are cautioned not to place undue reliance on these forward-looking statements, which reflect management's opinions only as of the date hereof. The Company undertakes no obligation to revise or publicly release the results of any revision to these forward-looking statements. Information on the potential factors that could affect the Company's actual results of operations is included in its filings with the Securities and Exchange Commission, including but not limited to its Annual Report on Form 10-K for the fiscal year ended December 31, 2000 and for the fiscal year ended December 31, 2001 which will be filed on or about March 15, 2002.