Item 1A. RISK FACTORS.

Except as provided below, there have been no material changes to the risk factors disclosed in Part I, Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2021.

Risks related to our Acquisition of US Ecology

We may experience difficulties completing the integration of US Ecology’s business, and we may incur unexpected expenses in connection with that integration.

Achieving the anticipated benefits of the acquisition of US Ecology will depend significantly on whether we can integrate US Ecology’s business in an efficient and effective manner. The integration may result in additional and unforeseen expenses, and the anticipated benefits of the integration plan may not be fully realized. We may not be able to accomplish the integration process smoothly, successfully or on a timely basis. Any inability of our management to successfully and timely integrate the operations of the two companies could have a material adverse effect on our consolidated financial condition, results of operations and cash flows.

We may not realize the anticipated synergies and related benefits from the acquisition of US Ecology fully or within the timing anticipated.

We may not be able to achieve the anticipated operating and cost synergies or the long-term strategic benefits of the acquisition with US Ecology fully or within the timing anticipated. For example, elimination of duplicative costs may not be fully achieved or may take longer than anticipated. For at least the first year after an acquisition, and possibly longer, the benefits from the acquisition will be offset by the costs incurred in integrating the businesses and operations. The inability to realize the full extent of the anticipated synergies or other benefits of the acquisition, or our encountering unexpected costs or delays in the integration process (which may delay the timing of such synergies or other benefits), could have a material adverse effect on our consolidated financial condition, results of operations and cash flows.

The hazardous and radioactive waste businesses acquired from US Ecology are subject to additional operational and litigation risks related to the handling of dangerous substances.

We are subject to unexpected occurrences related, or unrelated, to the routine handling of additional dangerous substances. A fire or other incident could impair the ability of one or more acquired facilities to continue to perform normal operations, which could have an adverse impact on our financial condition and results of operations. Improper handling of these substances could also violate laws and regulations resulting in fines and/or suspension of operations. The handling of radioactive, polychlorinated biphenyls and hazardous material subjects us to potential liability claims by employees, contractors, property owners, neighbors and others. There can be no assurance that our existing liability insurance is adequate to cover claims asserted against us or that we will be able to maintain adequate insurance in the future. Adverse rulings in judicial or administrative proceedings could also have a material adverse effect on our financial condition and results of operations. Our newly acquired hazardous and radioactive waste businesses are subject to international, state or local laws or regulations that restrict the transportation of such waste across international, state, county or other jurisdictional lines. Such laws and regulations could negatively affect our operations, resulting in increased costs of alternate disposal.

We could be subject to significant fines and penalties, and our reputation could be adversely affected, if our businesses, or third parties with whom we have a relationship, were to fail to comply with U.S. or foreign laws or regulations.

Some of our projects and business may be conducted in countries where corruption has historically been prevalent. It is our policy to comply with all applicable anti-bribery laws, such as the U.S. Foreign Corrupt Practices Act, and with applicable local laws of the foreign countries in which we operate, and we monitor our local partners’ compliance with such laws as well. Our reputation may be adversely affected if we were reported to be associated with corrupt practices or if we failed to comply with such laws. Such damage to our reputation could adversely affect our ability to grow our business. Additionally, violations of such laws could subject us to significant fines and penalties.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS.

Issuer Purchases of Equity Securities

The following table provides information relating to our purchases of shares of our common stock during the three months ended March 31, 2022:

a.In October 2020, our Board of Directors approved a $2.0 billion share repurchase authorization effective starting January 1, 2021 and extending through December 31, 2023. Share repurchases under the program may be made through open market purchases or privately negotiated transactions in accordance with applicable federal securities laws. While the Board of Directors has approved the program, the timing of any purchases, the prices and the number of shares of common stock to be purchased will be determined by our management, at its discretion, and will depend upon market conditions and other factors. The share repurchase program may be extended, suspended or discontinued at any time. As of March 31, 2022, no repurchased shares were pending settlement.

b.The total number of shares purchased as part of the publicly announced program were all purchased pursuant to the October 2020 authorization.

c.Shares that may be purchased under the program exclude shares of common stock that may be surrendered to satisfy statutory minimum tax withholding obligations in connection with the vesting of restricted stock units and performance stock units issued to employees.

ITEM 3. DEFAULTS UPON SENIOR SECURITIES.

None.

ITEM 4. MINE SAFETY DISCLOSURES.

None.