clh-20240410

CLEAN HARBORS, INC.0000822818DEF 14Afalse

9) CAP is calculated in accordance with the Item 402(v) of Regulation S-K. Reconciliations of Summary Compensation Table data to CAP for fiscal 2023, 2022, 2021, and 2020 for the PEOs and the Non-PEO NEOs are included in the table below:


	PEO (Alan S. McKim)
Year	2023		2022		2021		2020
Summary Compensation Table Total Compensation	$	2,296,564	$	6,241,356	$	5,612,724	$	3,828,532
Less: Grant Date Fair Value of Stock Awards (from Summary Compensation Table)	—		1,199,998		1,293,846		1,406,079
Add:
Change in Fair Value of Awards Granted During Year and Outstanding and Unvested as of Year-End	—		1,492,575		1,384,608		1,835,380
Change in Fair Value of Prior Year Awards Unvested as of Year-End	1,134,728		159,314		150,020		(218,891)
Change in Fair Value of Prior Year Awards that Vested During Year	189,183		79,802		747,590		(377,776)
Total Additions to Compensation Actually Paid	1,323,911		1,731,691		2,282,218		1,238,713
Compensation Actually Paid	$	3,620,475	$	6,773,049	$	6,601,096	$	3,661,166

	Co-PEO (Michael L. Battles)
Year	2023		2022		2021		2020
Summary Compensation Table Total Compensation	$	4,917,312	$	—	$	—	$	—
Less: Grant Date Fair Value of Stock Awards (from Summary Compensation Table)	2,931,746		—		—		—
Add:
Change in Fair Value of Awards Granted During Year and Outstanding and Unvested as of Year-End	5,086,269		—		—		—
Change in Fair Value of Prior Year Awards Unvested as of Year-End	1,250,254		—		—		—
Change in Fair Value of Prior Year Awards that Vested During Year	846,669		—		—		—
Total Additions to Compensation Actually Paid	7,183,192		—		—		—
Compensation Actually Paid	$	9,168,758	$	—	$	—	$	—

	Co-PEO (Eric W. Gerstenberg)
Year	2023		2022		2021		2020
Summary Compensation Table Total Compensation	$	4,938,543	$	—	$	—	$	—
Less: Grant Date Fair Value of Stock Awards (from Summary Compensation Table)	2,931,746		—		—		—
Add:
Change in Fair Value of Awards Granted During Year and Outstanding and Unvested as of Year-End	5,086,268		—		—		—
Change in Fair Value of Prior Year Awards Unvested as of Year-End	1,792,496		—		—		—
Change in Fair Value of Prior Year Awards that Vested During Year	1,360,591		—		—		—
Total Additions to Compensation Actually Paid	8,239,355		—		—		—
Compensation Actually Paid	$	10,246,152	$	—	$	—	$	—


	Average of Non-PEO NEOs
Year	2023		2022		2021		2020
Summary Compensation Table Total Compensation	$	1,344,687	$	2,755,014	$	2,931,679	$	2,343,696
Less: Grant Date Fair Value of Stock Awards (from Summary Compensation Table)	342,733		1,371,984		1,604,777		1,308,804
Add:
Change in Fair Value of Awards Granted During Year and Outstanding and Unvested as of Year-End	1,281,296		1,706,493		1,643,335		1,909,616
Change in Fair Value of Prior Year Awards Unvested as of Year-End	844,916		325,300		543,138		(179,536)
Change in Fair Value of Prior Year Awards that Vested During Year	251,540		(65,278)		318,653		(346,796)
Change in Fair Value of Prior Year Awards that Forfeited During Year	—		—		(95,753)		(155,894)
Total Additions to Compensation Actually Paid	2,377,752		1,966,515		2,409,373		1,227,390
Compensation Actually Paid	$	3,379,706	$	3,349,545	$	3,736,275	$	2,262,282

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No. )

Filed by the Registrant Proxy uncheck image.jpg

Filed by a Party other than the Registrant


Check the appropriate box:
			Preliminary Proxy Statement
			Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
			Definitive Proxy Statement
			Definitive Additional Materials
			Soliciting Material under §240.14a-12


Clean Harbors, Inc.


(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)


Payment of Filing Fee (Check all the boxes that apply):
			No fee required.
			Fee paid previously with preliminary materials.
			Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

April 10, 2024

Corporate Headquarters

42 Longwater Drive

Norwell, Massachusetts 02061

Tel. 781-792-5000

To Our Fellow Shareholders:

On behalf of the Board of Directors, it is my pleasure to invite you to attend the 2024 annual meeting of shareholders, to be held at 10:00 a.m., local time, on Wednesday, May 22, 2024, at our company’s training facility at 101 Philip Drive, Norwell, Massachusetts, located adjacent to our company’s headquarters.

Information about the annual meeting is presented on the following pages. In addition to the formal items of business, the meeting will include a report by members of management on our company operations. You will have an opportunity to ask questions of our management team if you attend the meeting in person.

For the 2024 annual meeting, we are again using the “notice and access” method of providing proxy materials via the internet. On or about April 10, 2024, we will be mailing to our shareholders a notice of internet availability of proxy materials, or “e-proxy notice,” containing instructions on how to access our 2024 proxy statement and the 2023 annual report to shareholders (including our 2023 Annual Report on Form 10-K).

Your vote is important. If you are unable to attend the meeting in person, it is important that your shares be represented and voted at the annual meeting. You may authorize your proxy to vote your shares over the internet, by telephone, or by mail as described under "General Matters - Proxy Solicitation" in the attached proxy statement.

Please note that under the current rules of the New York Stock Exchange, your broker will not be able to vote your shares at the annual meeting on the election of directors or on certain other proposals described in the attached proxy statement if you have not given your broker instructions on how to vote. Please be sure to give voting instructions to your broker so that your vote can be counted with respect to the election of directors and such other proposals.

Thank you for your continued support of Clean Harbors. We look forward to seeing those shareholders who are able to attend the annual meeting on May 22nd.


			Sincerely,

			Alan S. McKim
			Executive Chairman of the Board

CLEAN HARBORS, INC.

42 Longwater Drive

Norwell, Massachusetts 02061

___________________________

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

___________________________

Notice is hereby given that the 2024 annual meeting of shareholders of Clean Harbors, Inc. (the “Company”) will be held at 10:00 a.m., local time, on Wednesday, May 22, 2024, at the Company’s training facility located at 101 Philip Drive, Norwell, Massachusetts.

The annual meeting is being held:

1. To elect four (4) Class II members of the Board of Directors of the Company to serve until the 2027 annual meeting of shareholders and until their respective successors are duly elected and qualified;

2. To hold an advisory vote on the Company’s executive compensation;

3. To approve the Clean Harbors Employee Stock Purchase Plan;

4. To ratify the selection by the Audit Committee of the Company’s Board of Directors of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for the current fiscal year; and

5. To act upon such other business as may properly come before the meeting and any adjournment or postponement thereof.

Shareholders of record at the close of business on March 25, 2024, will be entitled to notice and to vote at the meeting.


			By order of the Board of Directors,

			Daniel T. Janis, Secretary
			April 10, 2024
			Norwell, Massachusetts

YOUR VOTE IS IMPORTANT. WHETHER OR NOT YOU PLAN TO ATTEND THE MEETING, PLEASE AUTHORIZE YOUR PROXY TO VOTE YOUR SHARES OVER THE INTERNET, BY TELEPHONE, OR BY MAIL AS DESCRIBED UNDER “GENERAL MATTERS - PROXY SOLICITATION” IN THE ATTACHED PROXY STATEMENT.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE ANNUAL MEETING OF SHAREHOLDERS TO BE HELD ON MAY 22, 2024: The Notice of Annual Meeting, Proxy Statement, and 2023 Annual Report to Shareholders (including the 2023 Annual Report on Form 10-K), are available for viewing, printing, and downloading at www.proxyvote.com.

TABLE OF CONTENTS



GENERAL MATTERS	1	EXECUTIVE COMPENSATION TABLES	36
		2023 Summary Compensation Table	36
BOARD OF DIRECTORS OVERVIEW	2	Grants of Plan-Based Awards	37
Board Leadership Structure	2	Outstanding Equity Awards at Fiscal Year-End	38
Corporate Governance Guidelines, Committee		Option Exercises and Stock Vested	40
Charters and Code of Ethics	3	Potential Payments Upon Termination or Change
Director Independence	3	of Control	41
Limitation on Other Board Services	4	CEO Pay Ratio Information	42
Board Committees	5
Audit Committee	5	PAY VERSUS PERFORMANCE	43
Compensation and Human Capital Committee	6
Corporate Governance and Sustainability		APPROVAL OF CLEAN HARBORS
Committee	7	EMPLOYEE STOCK PURCHASE PLAN	48
Environmental, Health and Safety		Key Features of the Plan	48
Committee	7	Administration	48
Ad Hoc Cyber Committee	8	Non-U.S. Sub-Plans	49
Compensation Committee Interlocks and		Eligibility	49
Insider Participation	8	Offering Periods	49
Communications to the Independent Directors	8	Payroll Deductions	50
Board Oversight of Risk Management	8	Purchase Price	50
Commitment to the Environment and		Purchase of Shares	50
Sustainability	8	Transferability	50
Executive Succession Planning	9	Withdrawals	50
No Political Contributions	9	Termination of Employment	51
		Change in Control	51
ELECTION OF DIRECTORS	9	Effective Date; Amendment and Termination
Board Matrix	10	of Plan	51
Board Nomination Process	11	U.S. Federal Income Tax Information	51
Current Directors and Nominees	12	New Plan Benefits	52
		Registration with the SEC	52
DIRECTOR COMPENSATION	17
		RATIFICATION OF SELECTION OF
EXECUTIVE OFFICERS	18	INDEPENDENT REGISTERED PUBLIC
		ACCOUNTING FIRM	53
RELATED PARTY TRANSACTIONS	20	Selection of the Company’s Independent
		Registered Public Accountant	53
ADVISORY VOTE ON EXECUTIVE		Audit and Related Fees	53
COMPENSATION	21	Audit Committee Report	54

COMPENSATION DISCUSSION AND		SECURITY OWNERSHIP OF CERTAIN
ANALYSIS	23	BENEFICIAL OWNERS AND
Executive Summary	23	MANAGEMENT	55
2023 Results Affecting Executive Compensation	26
Role of the Committee	27	SHAREHOLDER PROPOSALS	57
Consideration of Shareholder Responses	27	HOUSEHOLDING	57
Compensation Philosophy and Objectives	28	OTHER INFORMATION	57
Stock Ownership Guidelines	32	OTHER MATTERS	58
Insider Trading Policy and
Key Prohibited Transactions	33	EXHIBIT A - CLEAN HARBORS EMPLOYEE	A-1
Policies Related to Timing of Stock Option Grants	33	STOCK PURCHASE PLAN
Clawback Policy	33
Employment, Termination of Employment and
Change of Control Agreements and
Arrangements	34
Compensation Committee Report	35

CLEAN HARBORS, INC.

42 Longwater Drive

Norwell, MA 02061

_________________________

GENERAL MATTERS

_________________________

This proxy statement and the accompanying notice of the 2024 annual meeting of shareholders (the “annual meeting”) are being furnished to the holders of common stock, $0.01 par value (“common stock”), of Clean Harbors, Inc., a Massachusetts corporation (the “Company”, “Clean Harbors” or “we”), in connection with the solicitation of proxies by the Company’s board of directors (the “Board”) for use at the annual meeting and any adjournment or postponement thereof. The annual meeting will be held at the Company’s training facility located at 101 Philip Drive, Norwell, Massachusetts, on May 22, 2024, commencing at 10:00 a.m., local time.

Proxy Solicitation

For the 2024 annual meeting, we are again using the “notice and access” process permitted by the Securities and Exchange Commission (the “SEC”) to distribute proxy materials to our shareholders. This process allows us to post proxy materials on a designated website and notify shareholders of the availability of such proxy materials on that website by distributing a notice of internet availability of proxy materials, or “e-proxy notice,” rather than mailing hard copies of all of these materials. We believe this process lowers the cost of the annual meeting, expedites receipt of the meeting materials, and preserves natural resources.

The e-proxy notice also includes instructions for how to request a paper copy of our proxy materials or an electronic copy by e-mail. Your request to receive proxy materials in paper form by mail or electronically by e-mail will remain in effect for future meetings until you revoke it.

If your shares are registered directly in your name with our transfer agent, American Stock Transfer and Trust Company, you are considered the shareholder of record with respect to those shares and the e-proxy notice is being sent directly to you. As a shareholder of record, you may vote in person at the annual meeting or vote by proxy. Whether or not you plan to attend the annual meeting in person, we urge you to vote by telephone, via the internet, or, if you request a paper copy of the proxy materials, by completing, signing, dating, and returning the proxy card provided. You may revoke your proxy before it is exercised at the annual meeting by delivery of written revocation or a subsequently dated proxy to the Secretary of the Company, by voting again by telephone or via the internet, or by voting in person at the annual meeting. Attendance at the annual meeting will not, by itself, revoke a proxy.

If your shares are held in “street name” by a broker or other nominee, you are considered the beneficial owner of such shares and a form of e-proxy notice is being forwarded to you by the broker or nominee which is the shareholder of record with respect to those shares. Unless you have requested that you receive proxy materials in paper form, your broker will notify you how to access this proxy statement in electronic form and provide you with instructions on how to vote your shares. As a beneficial owner of your shares, you have the right to direct your broker or nominee on how to vote the shares held in your account. You may provide this direction by following the instructions on the form of voting instructions you receive from your broker or the e-proxy notice you receive. Although you have the right to direct how your shares are voted, the entity that holds your shares is the shareholder of record for purposes of voting at the annual meeting. Accordingly, because you are not the shareholder of record, you may not vote your shares in person at the annual meeting unless you request and obtain a valid proxy from your broker or nominee giving you the right to vote the shares at the meeting. If your shares are held of record by a broker or nominee and you wish to change your voting instructions, you must contact your broker or nominee to revoke any prior voting instructions.

If you wish to attend the annual meeting in person, please bring with you the e-proxy notice you have received and a government-issued proof of identity (such as a driver’s license).

The cost of this solicitation shall be borne by the Company. Solicitations of proxies by telephone or in person may be made by the Company’s directors, officers, or other employees, but any such solicitation will be carried on during working hours and for no additional cost, other than the time expended and telephone charges in making such solicitation. This proxy statement and the accompanying proxy form are first being made available to shareholders beginning on or about April 10, 2024.

Information as to Voting Securities

On March 25, 2024, the record date for the annual meeting, there were 54,637,464 issued and outstanding shares of common stock. The presence in person or by proxy of a majority of shares of common stock entitled to vote is necessary to constitute a quorum at the annual meeting. Each share is entitled to one vote. Only shareholders of record at the close of business on the record date will be entitled to vote at the annual meeting. Votes cast by proxy or in person at the annual meeting will be counted by one or more persons appointed by the Company to act as election inspectors for the annual meeting.

At the annual meeting, the shareholders will vote upon proposals to (i) elect four Class II directors, (ii) approve an advisory vote on executive compensation, (iii) approve the Clean Harbors Employee Stock Purchase Plan, and (iv) ratify the selection by the Audit Committee of the Company’s Board of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for the current fiscal year.

Election of each of the Class II directors will require the affirmative vote of the holders of a majority of the total shares of common stock cast on the election of such nominee at the meeting, and votes withheld from any nominee for election as a director will have the effect of “against” votes. Approval of (i) the advisory vote on executive compensation, (ii) the Clean Harbors Employee Stock Purchase Plan, and (iii) ratification of the selection by the Board’s Audit Committee of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for the current fiscal year will each require the affirmative vote of the holders of a majority of the shares represented at the meeting and voted on such proposals. Any abstentions and broker “non-votes,” will be counted as shares present or represented for purposes of determining the presence of a quorum for the meeting but will have no impact on the election of directors or on the other proposals described above.

Broker “non-votes” occur when a broker holding shares in “street name” votes on one proposal, but does not vote on another proposal because the broker does not have discretionary voting power and has not received instructions from the beneficial owner of such shares. Usually, this would occur when brokers holding stock in “street name” have not received voting instructions from clients, in which case the brokers (as holders of record) are generally permitted by the rules of the New York Stock Exchange to vote only on “discretionary” matters. Under the New York Stock Exchange's current rules, brokers will not be permitted to vote shares for which they have not received voting instructions on (i) election of the Class II directors, (ii) advisory approval of executive compensation, or (iii) approval of the Clean Harbors Employee Stock Purchase Plan. However, under such rules, the proposed ratification of the selection by the Audit Committee of Deloitte & Touche LLP as the Company's independent registered public accounting firm for the current fiscal year is a “discretionary” matter, and brokers will therefore generally be able to vote shares held in “street name” on such matter without receiving instructions from the beneficial holders of such shares.

BOARD OF DIRECTORS OVERVIEW

Board Leadership Structure

Clean Harbors, Inc. is a Massachusetts corporation, and by statute all public Massachusetts corporations have a staggered board of directors, with either two or three classes of directors, unless the corporation elects to be exempt from this statutory requirement by vote of its board of directors or of two-thirds of each class of stock outstanding. The Board has not elected to exempt, or to recommend that the shareholders exempt, the Company from this statutory requirement because the Board believes that a staggered board promotes continuity and stability.

Alan S. McKim, the Company’s founder, now serves and has served since the Company’s formation in 1980 as Chairman of the Board and, until March 31, 2023, Mr. McKim had also served as the Company’s Chief Executive Officer and President. Effective March 31, 2023, the Board appointed Michael L. Battles, formerly the Company’s Chief Financial Officer, and Eric W. Gerstenberg, formerly the Company’s Chief Operating Officer, as the Co-Chief Executive Officers and Co-Presidents of the Company. Mr. McKim remains a director of the Company, as the Executive Chairman of the Board and has also been appointed as the Company’s Chief Technology Officer. Neither Mr. Battles nor Mr. Gerstenberg serves as a director on our Board.

The Board also has a lead independent director, Edward G. Galante (the “Lead Director”), nominated by the Board’s Corporate Governance and Sustainability Committee and elected by the full Board, effective upon completion of our 2022 annual meeting. The Lead Director is an independent director who presides over executive sessions of the Board, serves as a contact person for correspondence with the independent members of the Board, works with the Executive Chairman and Co-Chief Executive Officers in establishing the agenda for Board meetings, and meets with the Executive Chairman and the Co-Chief Executive Officers in person or virtually at least quarterly. Mr. Galante has served as a director of the Company since

2010, and currently serves as a member of the Environmental, Health and Safety Committee. Previously, Mr. Galante was a member of the Compensation and Human Capital Committee and the Corporate Governance and Sustainability Committee of the Board.

The Board requires that the chairperson for each of the Board’s committees should periodically change. Each independent director (after a short transition period for new directors) is therefore expected to serve on at least two committees except for the Lead Director, who is eligible to attend all committee meetings but may only vote on committee matters if he or she is a member of such committee. As a matter of practice, the lead director does not serve on any committees.

The Board believes its current leadership structure to be the most appropriate for the Company at this time. As described above, neither of the Company’s two Co-CEOs is now a director of the Company, but Mr. McKim, the Company’s founder and former CEO, continues to serve as Executive Chairman of the Board and has a thorough knowledge of the Company’s business and an impressive track record in managing the Company for over 40 years. As the Company's largest individual shareholder, Mr. McKim’s interests are also significantly aligned with those of the other shareholders. The Board also believes this structure is appropriate because as described below, all of the Company’s directors except for Mr. McKim are “independent” as defined under New York Stock Exchange (“NYSE”) rules and, as described above, the Board has an independent Lead Director selected from among the independent directors and all of the committees of the Board consist exclusively of independent directors.

Corporate Governance Guidelines, Committee Charters and Code of Ethics

The Company’s Board has adopted Corporate Governance Guidelines, charters for each of the Board’s committees, and a Code of Ethics which sets forth standards of ethical professional conduct for the officers, directors and employees of the Company and its subsidiaries. Each of those documents is posted on the Company’s website at www.cleanharbors.com under “Investors - Corporate Governance.” A copy of these documents may also be obtained without cost by writing to Clean Harbors, Inc., 42 Longwater Drive, Norwell, MA 02061, Attention: Executive Office. In the event that any waiver of the Code of Ethics is approved by the Audit Committee or the full Board of Directors, such waiver would be posted on the Company’s website. In 2023, and through the date of this proxy filing, there have been no waivers granted.

Director Independence

The Corporate Governance Guidelines adopted by the Board require that at least a majority of the Board be “independent,” as defined by the rules of the NYSE on which the Company’s common stock is listed. To be considered independent under the NYSE rules, the Board must affirmatively determine that a director does not, except as a director or shareholder, have a direct or indirect material relationship with the Company (either directly or as a partner, shareholder or officer of an organization that has a relationship with the Company). In making that determination, the Board must consider all relevant facts and circumstances. In particular (but without limitation as to the potential reasons for which a director might not be determined to be independent), a director is not independent if:

•The director is, or has been within the last three years, an employee of the Company or the director has an immediate family member who is, or has been within the last three years, an executive officer of the Company.

•The director has received, or has an immediate family member who has received, during any 12-month period within the last three years, more than $120,000 in direct compensation from the Company, other than director and committee fees, stock incentives awarded to non-employee directors of the Company, and pension or other forms of deferred compensation for prior service (provided such deferred compensation is not contingent in any way on continued service).

•(A) The director or an immediate family member of the director is a current partner of the Company’s internal or external auditor; (B) the director is a current employee of the Company’s external auditing firm; (C) the director has an immediate family member who is a current employee of the Company’s external auditing firm and who participates in the firm’s audit, assurance or tax compliance (but not tax planning) practice; or (D) the director or an immediate family member of the director is, or has been within the last three years, a partner or employee of the Company’s external auditing firm and personally worked on the Company’s audit within that time.

•The director or an immediate family member of the director is, or has been within the last three years, employed as an executive officer of another company where any of the Company’s present executive officers serve or served at the same time on that other company’s compensation committee.

•The director is a current employee, or an immediate family member of the director is a current executive officer, of a company that has made payments to or received payments from the Company for property or services in an amount which, in any of the last three fiscal years, exceeds the greater of $1 million or 2% of such other company’s consolidated gross revenues.

The Board also has established the following categorical standards to assist it in determining director independence in accordance with the NYSE rules:

•Stock Ownership. Ownership of stock in the Company by a director or a director’s immediate family is not considered a relationship which would adversely impact a director’s independence.

•Commercial Relationships. The following commercial relationships are not considered material relationships that would impair a director’s independence: (i) if a director of the Company is an executive officer or an employee of, or an immediate family member of a director is an executive officer of, another company that does business with the Company and the annual sales to, or purchases from, the Company are less than 1% of the annual revenues of such other company, and (ii) if a director of the Company is an executive officer of another company which is indebted to the Company, or to which the Company is indebted, and the total amount of either company’s indebtedness to the other is less than 2% of the total consolidated assets of the company for which he or she serves as an executive officer.

•Charitable Relationships. The following charitable relationship will not be considered a material relationship that would impair a director’s independence: if a director, or an immediate family member of the director, serves as an executive officer, director or trustee of a charitable organization, and the Company’s discretionary charitable contributions (if any) to that charitable organization in any single fiscal year are less than 1% or $500,000, whichever is less, of that charitable organization’s annual consolidated gross revenues.

•Personal Relationships. Except as described above with respect to transactions which involve payments made to or by the Company in excess of the respective amounts there described, the following personal relationship will not be considered to be a material relationship that would impair a director’s independence: if a director, or immediate family member of the director, receives from, or provides to, the Company products or services in the ordinary course and on substantially the same terms as those prevailing at the time for comparable products or services provided to unaffiliated third parties.

For relationships not qualifying within the foregoing guidelines, the determination of whether the relationship is material, and therefore whether the director is independent, shall be made by the directors who satisfy the foregoing independence guidelines. For purposes of these guidelines, “immediate family member” has the meaning defined in the NYSE rules. The Board and its Corporate Governance and Sustainability Committee monitor the Board’s compliance with the NYSE requirements for director independence on an ongoing basis.

In accordance with current NYSE rules and the Board’s own categorical standards of independence, the Board has determined that the following current non-employee directors are “independent” and have no direct or indirect material relationship with the Company except as a director and shareholder: Edward G. Galante, Karyn Polito, John T. Preston, Alison A. Quirk, Marcy L. Reed, Andrea Robertson, Lauren C. States, Shelley Stewart, Jr., John R. Welch, and Robert J. Willett. Accordingly, the Board has determined that 10 out of the total of 11 current directors are independent. The Board has also determined that, to the extent (if any) the Company has had during the past three years any commercial relationships with any of the entities with which any of the independent directors are affiliated, those relationships fall below the categorical standards for commercial relationships, were established in the ordinary course of business on an arms-length basis, and are not material to the Company or those individuals or entities. The Board has determined that Alan S. McKim is not independent because he is an employee of the Company.

Limitation on Other Board Services

The Board believes that its members should not be prohibited from serving on boards or committees of other organizations, provided there is no actual or apparent conflict of interest between Clean Harbors and such other organizations and provided the member’s service with such other organizations will not unduly impinge upon his/her commitment to Clean Harbors. The Board has, however, developed a guideline regarding the number of public company boards on which a director may serve. The number of public company boards on which a director may serve, including the Board, is limited to (i) in the case of a director who is not also a public company chief executive officer, four (4) boards of directors and (ii) in the case of a director who serves as a chief executive officer or in an equivalent position of a public company, two (2) boards of directors in addition to their employer’s board. The Corporate Governance and Sustainability Committee will take into account the

nature of and time involved in a director’s service on other boards and committees in evaluating the suitability of that person to serve as a director of Clean Harbors. Any director is expected to offer his or her resignation from the Board in the event of a material change in the principal job responsibilities held at the time of his or her election to the Board.

Board Committees

The Board has established four standing committees: the Audit Committee, the Compensation and Human Capital Committee, the Corporate Governance and the Sustainability Committee, and the Environmental, Health and Safety Committee. The Board has determined that each committee of the Board consists solely of non-employee “independent directors” as defined by the NYSE rules which are applicable to membership on such committees, and that each committee member is free of any relationship that would interfere with his or her ability to exercise independent judgment. Based upon their training and experience, as described below under “Election of Directors,” the Board has also determined that Marcy L. Reed and Andrea Robertson, who are now members of the Audit Committee, each qualify as an “audit committee financial expert” as defined by Item 407(d)(5)(ii) of Regulation S-K under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and that Karyn Polito and Shelley Stewart, Jr. the other current members of the Audit Committee, are financially literate as required by the NYSE listing rules. All members of the committees are appointed by the Board, and each committee operates under a charter approved by the Board and available on the Company’s website at www.cleanharbors.com under “Investors - Corporate Governance.” Copies may also be obtained without cost by writing to Clean Harbors, Inc., 42 Longwater Drive, Norwell, MA 02061, Attention: Executive Office.

The following table describes the current members of the four standing committees of the Board:

In September 2023, the Board established a special committee (“Ad Hoc Cyber Committee”) with the goal of reviewing the Company’s overall cybersecurity risk and response landscape. The Ad Hoc Cyber Committee is comprised of members with diverse expertise including risk management, technology and finance with two members holding Cybersecurity Oversight Certificates issued by the National Association of Corporate Directors and Carnegie Mellon University. The members of the Ad Hoc Cyber Committee include Mr. Welch (chair), Mr. Preston, Ms. Reed and Ms. States.

Audit Committee

The Audit Committee consists of four independent directors pursuant to applicable NYSE and SEC rules and assists the Board in fulfilling its oversight responsibility of the adequacy and integrity of the Company’s financial statements, financial reporting process, and internal controls over financial reporting. The primary responsibilities of the Audit Committee are to select the Company’s independent registered public accounting firm, review the scope of, approach to and results of audit work, meet with and review the activities of the Company’s internal auditors and the Company’s independent registered public accounting firm, fulfill oversight responsibilities relating to the integrity of the Company’s financial

statements, related party transactions, and policies with respect to risk assessment and risk management, and review the Company’s policies regarding employee complaints and a summary of any complaints received.

In fulfillment of its responsibilities, among other things, the Audit Committee:

•discusses with senior members of the Company’s financial management team and the independent auditors matters associated with accounting principles, critical accounting policies, significant accounting judgments and estimates, and internal controls over financial reporting;

•holds separate private sessions, during its regularly scheduled meetings, with senior members of the Company’s financial management team, with the independent auditors, with the Vice President of Internal Audit, and on its own, at which candid discussions regarding financial management, accounting, auditing, and internal control matters take place;

•receives periodic updates on management’s process to assess the adequacy of the Company’s system of internal control over financial reporting and management’s conclusions on the effectiveness of the Company’s internal control over financial reporting;

•discusses with the independent auditors the Company’s internal control assessment process, management’s assessment with respect thereto, and the independent auditors’ evaluation of the Company’s system of internal control over financial reporting;

•reviews and discusses with management the Company’s earnings releases and quarterly and annual reports on Form 10-Q and Form 10-K, respectively, prior to filing with the SEC;

•reviews the Company’s internal audit plan and the performance of the Company’s internal audit function;

•reviews with senior members of the Company’s financial management team, the independent auditors, and the Vice President of Internal Audit, the overall scope and plans for their respective audits, the results of internal and external audits, evaluations by management and the independent auditors of the Company’s internal controls over financial reporting, and the quality of the Company’s financial reporting;

•discusses with the Company’s counsel legal, income tax, and regulatory matters that may have a material impact on the Company’s financial statements, and compliance policies and programs, including corporate securities trading policies;

•discusses with management guidelines and policies governing the process by which senior management of the Company and the relevant departments of the Company, including the internal auditing department, identify, assess, and manage the Company’s exposure to risk, as well as the Company’s major financial risk exposures and the steps management has taken to monitor and control such exposure;

•selects the Company’s independent registered public accounting firm and administers pre-approval policies and determines its compensation;

•reviews the Company’s Related Party Transaction Policies and the transactions, which are described in this proxy statement under “Related Party Transactions;” and

•participates, with representatives of management and of the independent auditors, in additional discussions, as requested by the Audit Committee, on areas of the Company’s operations.

The Audit Committee held six meetings during 2023.

Compensation and Human Capital Committee

The Compensation and Human Capital Committee (the “C&HC Committee”) consists of independent directors pursuant to applicable NYSE rules and its primary responsibilities are to (i) recommend to the full Board the total compensation (e.g. base salary, management incentive cash bonus, and equity compensation) for the Chief Executive Officer or Co-Chief Executive Officers, which compensation is then approved by all the Company’s independent directors, (ii) review and approve the total compensation for the executive officers and other senior management, (iii) administer the Company’s cash incentive bonus plans for senior management and equity incentive plans, and (iv) periodically review certain aspects of the Company’s policies relating to compensation and human capital management including succession planning. The C&HC Committee also periodically reviews succession planning for the CEO or Co-CEOs and other key positions, as

determined by the C&HC Committee and management, and reviews and monitors management policies and strategies relating to the Company’s human capital management function including, for example, those relating to recruitment, retention, engagement, talent development and diversity, equity and inclusion.

Under its charter, the C&HC Committee has authority to select and retain its own executive compensation consultants, legal counsel, and other advisors to assist the C&HC Committee in its determinations. In connection with each such selection, the Committee considers factors that could bear on the independence of each such advisor. Following the completion of each fiscal year, the C&HC Committee evaluates the levels of success of the CEO or Co-CEOs, executive officers and other senior management of the Company in achieving their goals during the prior year and, based upon the degree of their success, determines the amount of bonuses (if any) payable to the CEO or Co-CEOs, executive officers and other senior management of the Company and the extent to which restricted shares with performance criteria are earned and will vest (subject to continued employment).

The C&HC Committee held five meetings during 2023, and acted via unanimous written consent in lieu of meeting three times.

Corporate Governance and Sustainability Committee

The Corporate Governance and Sustainability Committee consists of independent directors pursuant to applicable NYSE rules and its primary responsibilities are to serve as a nominating committee for directors, including the Lead Director, recommend structures of Board committees, review director independence and compensation, and assist the Board in reviewing the performance of the Board and the CEO or Co-CEOs. The Corporate Governance and Sustainability Committee reviews the Company’s framework for development of policies and programs regarding environmental, sustainability and governance (“ESG”) matters and periodically assesses the Company’s performance thereunder. In particular, prior to any related public disclosure, the Corporate Governance and Sustainability Committee oversees the Company’s sustainability targets and the Company’s sustainability reporting and reports the results therefore to the full Board.

The Corporate Governance and Sustainability Committee held four meetings during 2023, and acted via unanimous written consent in lieu of meeting once.

Environmental, Health and Safety Committee

The Environmental, Health and Safety Committee consists of independent directors pursuant to applicable NYSE rules and its primary responsibilities are to fulfill the Board’s oversight responsibilities for the Company’s policies and practices related to human health and safety, operational safety, and regulatory and environmental compliance. Among other matters, the Environmental, Health and Safety Committee:

•reviews the effectiveness of the Company’s major compliance programs with respect to regulatory requirements including, but not limited to, the Company’s policies and procedures for monitoring employee health and safety and regulatory and environmental compliance;

•oversees the risk management associated with the Company’s environmental, health and safety policies, practices, and performance, including an evaluation of the effectiveness of management’s programs for compliance with applicable laws and regulations;

•reviews and monitors emerging environmental, health and safety issues, as well as proposed laws and regulations, and their potential impact on the Company, including its operations, financial results, risk exposure and reputation;

•reviews management’s evaluation of the potential environmental, health and safety effects and/or risk exposure related to projects for which management is seeking Board approval and makes such recommendations to the Board with respect thereto as the Environmental, Health and Safety Committee may deem advisable;

•reviews significant capital expenditures that may have a material environmental, health and safety impact;

•periodically conducts site visits to Company operating locations to assess environmental, health and safety programs and practices;

•reviews the Company’s major environmental, health and safety liabilities reported in the Company’s financial statements;

•reviews the Company’s benchmarking of environmental, health and safety programs of other companies (within and outside of our industry) to endeavor that best practices are being implemented; and

•in coordination with other committees of the Board, reviews and, as applicable, approves information relating to sustainability, legislative, regulatory, and other relevant policies, practices, or performance measures for inclusion in the Company’s Sustainability Report and SEC filings with the applicable ESG reporting frameworks.

The Environmental, Health and Safety Committee held four meetings during 2023.

Ad Hoc Cyber Committee

As noted above, the Board established a new Ad Hoc Cyber Committee, whose primary responsibilities are to identify, evaluate and monitor cyber-risk management concerns and determine how those concerns align with the Company’s risk profile. The Ad Hoc Cyber Committee identifies priorities and establishes cyber oversight criteria as part of good corporate governance. In connection with such determination, the Ad Hoc Cyber Committee considers issues relating to confidentiality, integrity, availability and compliance with applicable legal and regulatory requirements and national institute standards and technology.

The Ad Hoc Cyber Committee held one meeting during 2023.

Compensation Committee Interlocks and Insider Participation

No person who served as a member of the Board's Compensation and Human Capital Committee during the last fiscal year (Mr. Galante, prior to his appointment as Lead Director on May 24, 2023, Ms. Quirk, Mr. Pre

SEC Form DEF 14A filed by Clean Harbors Inc.