EXHIBIT 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in Registration Statement No.333-166963 on Form S-8 of our reports dated February 26, 2020, relating to the financial statements of Clean Harbors, Inc. and the effectiveness of Clean Harbors, Inc.'s internal control over financial reporting appearing in this Annual Report on Form 10-K for the year ended December 31, 2019.

/s/ Deloitte & Touche LLP

Boston, Massachusetts

February 26, 2020