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collect within a particular jurisdiction to facilities not owned or controlled by us, which could increase our costs and reduce our revenues.

Our financial and operating performance may be affected by the inability to renew landfill operating permits, obtain new landfills and expand existing ones.

We currently own and/or operate 9391 landfills and one development stage landfill throughout the United States and Canada. Our ability to meet our financial and operating objectives may depend in part on our ability to acquire, lease, or renew landfill operating permits, expand existing landfills and develop new landfill sites, especially in our E&P waste business.sites. It has become increasingly difficult and expensive to obtain required permits and approvals to build, operate and expand solid waste management facilities, including landfills and transfer stations. Although the process generally takes less time, the process of obtaining permits and approvals for E&P landfills has similar uncertainties. Operating permits for landfills in states and provinces where we operate must generally be renewed every five to ten years, although some permits are required to be renewed more frequently. These operating permits often must be renewed several times during the permitted life of a landfill. The permit and approval process is often time consuming, requires numerous hearings and compliance with zoning, environmental and other requirements, is frequently challenged by special interest and other groups, including those utilizing social media to further their objectives, and may result in the denial of a permit or renewal, the award of a permit or renewal for a shorter duration than we believed was otherwise required by law, or burdensome terms and conditions being imposed on our operations. For example, see the discussions regarding the Los Angeles County, California Landfill Expansion Litigation—A. Chiquita Canyon, LLC Lawsuit Against Los Angeles County in Note 12, “Commitments and Contingencies,” of our consolidated financial statements included in Item 8 of this Annual Report on Form 10-K. This process may be further complicated by the COVID-19 pandemic, which may impact the timeliness of the receipt of approvals and permits.  We may not be able to obtain new landfill sites or expand the permitted capacity of our existing landfills when necessary, and may ultimately be required to expense up to the carrying value of the landfill or expansion project, less the recoverable value of the property and other amounts recovered. Obtaining new landfill sites is important to our expansion into new, non-exclusive solid waste markets and in our E&P waste business. If we do not believe that we can obtain a landfill site in a non-exclusive market, we may choose not to enter that market. Expanding existing landfill sites is important in those markets where the remaining lives of our landfills are relatively short. We may choose to forego acquisitions and internal growth in these markets because increased volumes would further shorten the lives of these landfills. Any of these circumstances could adversely affect our operating results.

Lower crude oil prices may adversely affect the level of exploration, development and production activity of E&P companies and the demand for our E&P waste services.

Lower crude oil prices and the volatility of such prices may affect the level of investment and the amount of linear feet drilled in the basins where we operate, as it may impact the ability of E&P companies to access capital on economically advantageous terms or at all. In addition, E&P companies may elect to decrease investment in basins where the returns on investment are inadequate or uncertain due to lower crude oil prices or volatility in crude oil prices. Such reductions in capital spending would negatively impact E&P waste generation and therefore the demand for our services. Further, we cannot provide assurances that higher crude oil prices will result in increased capital spending and linear feet drilled by our customers in the basins where we operate.

Increases in labor costs and limitations on labor availability could impact our financial results.

Labor is one of our highest costs and relatively small increases in labor costs per employee could materially affect our cost structure.  We compete with other businesses in our markets for qualified employees and the labor supply is sometimes tight in our markets, which can drive higher turnover and increase the time it takes to fill job openings.  In our E&P waste business, for example, we are exposed to the cyclical variations in demand that are particular to the development and production of oil and natural gas.  A shortage of qualified employees in solid waste or E&P, including due to the COVID-19 pandemic in our markets, would require us to incur additional costs related to wages and benefits, to hire more expensive temporary employees or to contract for services with more expensive third-party vendors.  In addition, higher turnover can result in increased costs associated with recruiting and training; it can also impact operating costs, including maintenance and risk.  As an essential services provider, in March 2020 we implemented temporary emergency wages, supplemental pay and extended benefits programs for our frontline workforce and other employees directly or indirectly affected by the COVID-19 pandemic, which were  partially offset by cost reductions in other areas.

Increases in capital expenditures could impact our financial results.

Increases in fleet, equipment and landfill construction costs due to the imposition of tariffs on steelcost pressures, acquisitions and other items, as well as other cost pressures,new contracts could result in capital expenditures being higher than anticipated. In addition, acquisitions and new contracts may increase capital expenditures. This could impact our ability to generate free cash flow in line with our expectations.

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Lower crude oil prices have and may continue to adversely affect the level of exploration, development and production activity of E&P companies and the demand for our E&P waste services.

Lower crude oil prices and the volatility of those prices may affect the level of investment and the amount of linear feet drilled in the basins where we operate, as it may impact the ability of E&P companies to access capital on economically advantageous terms or at all. In addition, E&P companies may elect to decrease investment in basins where the returns on investment are inadequate or uncertain due to lower crude oil prices or volatility in crude oil prices.  Recent declines in the price of crude oil to historic lows have resulted in announced reductions to capital spending plans by E&P companies.  Such reductions in capital spending would be expected to negatively impact E&P waste generation and therefore the demand for our services.  Energy transition, or a transformation of the global energy sector from fossil-based systems of energy production and consumption to renewable energy sources, could also affect investments by E&P companies in the basins where we operate.  Given the unexpected oversupply of oil and the decreased demand for oil associated with the economic slowdown caused by the COVID-19 pandemic, we cannot estimate when crude oil prices will increase.  Further, we cannot provide assurances that higher crude oil prices will result in increased capital spending and linear feet drilled by our customers in the basins where we operate.

A portion of our growth and future financial performance depends on our ability to integrate acquired businesses, and the successperformance of our acquisitions.

A component of our growth strategy involves achieving economies of scale and operating efficiencies by growing through acquisitions. We may not achieve these goals unless we effectively combine the operations of acquired businesses with our existing operations. Similar risks may affect contracts that we are awarded to operate municipally-owned assets, such as landfills. In addition, we are not always able to control the timing of our acquisitions. Our inability to complete acquisitions within the time frames that we expect may cause our operating results to be less favorable than expected, which could cause our share price to decline.

Even if we are able to make acquisitions on advantageous terms and are able to integrate them successfully into our operations and organization, some acquisitions may not fulfill our anticipated financial or strategic objectives in a given market due to factors that we cannot control, such as market conditions, including the price of crude oil, market position, competition, customer base, loss of key employees, third-party legal challenges or governmental actions.  In addition, we may change our strategy with respect to a market or acquired businesses and decide to sell such operations at a loss, or keep those operations and recognize an impairment of goodwill and/or intangible assets. Similar risks may affect contracts that we are awarded to operate municipally-owned assets, such as landfills.

Some acquisitions may not fulfill our anticipated financial or strategic objectives in a given market due to factors that we cannot control, such as market conditions, including the price of crude oil, market position, competition, customer base, loss of key employees, third-party legal challenges or governmental actions. In addition, acquisitions may have liabilities or risks that we fail or are unable to discover, or that become more adverse to our business than we anticipated at the time of acquisition. As a successor owner, we may be legally responsible for those liabilities that arise from businesses that we acquire, whether we expressly assume them or not, including as a result of sellers not having sufficient funds to perform their obligations or liabilities being imposed on us under various regulatory schemes and other applicable laws. In addition, our insurance program may not cover such sites and will not cover liabilities associated with some environmental issues that may have existed prior to attachment of coverage. For example, see the discussions regarding the Lower Duwamish Waterway Superfund Site Allocation Process in Note 12, “Commitments and Contingencies,” of our consolidated financial statements included in Item 8 of this Annual Report on Form 10-K. A successful uninsured claim against us could harm our financial condition or operating results. Additionally, there may be other risks of which we are unaware that could have an adverse effect on businesses that we acquire or have acquired, such as foreign, state, provincial and local regulation and administrative risks. Another example of risk is interested parties that may bring actions against us in connection with operations that we acquire or have acquired. Furthermore, risks or liabilities we judge to be not material or remote at the time of acquisition may develop into more serious risks to our business. Any adverse outcome resulting from such risks or liabilities could harm our operations and financial results and create negative publicity, which could damage our reputation, competitive position and share price.

The seasonal nature of our business and “event-driven” waste projects cause our results to fluctuate.

Based on historic trends, excluding any impact from the COVID-19 pandemic or an economic recession, we would expect our operating results to vary seasonally, with revenues typically lowest in the first quarter, higher in the second and third quarters, and lower in the fourth quarter than in the second and third quarters. We expect the fluctuation in our revenues between our highest and lowest quarters to be approximately 12%10%. This seasonality reflects the lower volume of

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solid waste generated during the late fall, winter and early spring because of decreased construction and demolition activities during the winter months in Canada and the U.S., and reduced E&P activity during harsh weather conditions. Conversely, mild winter weather conditions may reduce demand for oil and natural gas, which may cause our customers to curtail their drilling programs, which could result in production of lower volumes of E&P waste.

Adverse winter weather conditions, including severe storms or extended periods of inclement weather, slow waste collection activities, resulting in higher labor and operational costs. Greater precipitation in the winter increases the weight of collected solid waste, resulting in higher disposal costs, which are calculated on a per ton basis. Certain weather conditions, including severe storms, may result in temporary suspension of our operations, which can significantly impact the operating results of the affected areas. Conversely, weather-related occurrences and other “event-driven” waste projects can boost revenues through heavier weight loads or additional work for a limited time. These factors impact period-to-period comparisons of financial results, and our share price may be negatively affected by these variations.

Our results will be affected by changes in recycled commodity prices and quantities.

quantities.

We provide recycling services to some of our customers. The majority of the recyclables we process for sale areinclude paper products and plastics that are shipped to customers in the United States, andas well as other markets, including Asia. The sale prices of and the demand for recyclable commodities particularly paper products, are frequently volatile and when they decline, our revenues, operating results and cash flows will be affected. In 2017,The value of plastics are influenced by the Chinese government announcedvolatility of crude oil prices, and there has been a banresulting decline in the value of plastic recyclables associated with the precipitous drop in the value of crude in 2020.  The value of paper products are impacted by demand, which is often influenced by quality concerns, which have resulted in the imposition of restrictions by other countries, including China, on the import of certain materials, including mixed waste paper and mixed plastics, effective January 1, 2018, as well as extremely restrictive quality requirements effective March 1, 2018 that are difficult for the industry to achieve. Single stream MRFsrecyclables.

Singlestream recycling facilities process a wide range of commingled materials and tend to receive a higher percentage of non-recyclables, particularly in residential collection, which results in increased processing and residual disposal costs to achieve quality standards. Also in 2017, the Chinese government began to limit the flow of material into the country by restricting the issuance of required import licenses, and this practice continued in 2018.

The new quality standards imposed by China and the restrictions on import licenses have made the sale of recycled commodities more difficult and have resulted in lower prices for such commodities, higher operating costs or additional capital expenditures in order to meet the requirements. As a result, we have increased the fees that we charge customers at our recycling facilities in order to recover the higher processing costs for recyclables.  This may result in lower recycled commodity volumes at our MRFs,recycling facilities, as customers may elect to pursue cheaper alternatives for processing or disposal.  Any such reduction could impact revenues, operating results and cash flow.  Some of our recycling operations offer rebates to customers based on the market prices of commodities we buy to process for resale. Therefore, if we recognize increased revenues resulting from higher prices for recyclable commodities, the rebates we pay to suppliers will also increase, which also may impact our operating results.  To the extent that there is an economic slowdown, including the one associated with the COVID-19 pandemic, a resulting decline in demand for recycled commodities could impact our revenues, operating results and cash flow.

Our results will be affected by changes in the value of renewable fuels.

fuels.

Variations in the price of methane gas and other energy-related products that are marketed and sold by our landfill gas recovery operations affect our results. Pursuant to the Energy Independence and Security Act of 2007, the United States EPA has promulgated the Renewable Fuel Standards, or RFS, which require refiners to either blend "renewable fuels," such as ethanol and biodiesel, into their transportation fuels or to purchase renewable fuel credits, known as renewable identification numbers, or RINs, in lieu of blending. In some cases, landfill gas generated at our landfills in the United States and Canada qualifies as a renewable fuel for which RINs are available. The price of RINs has been extremely volatile and is dependent upon a variety of factors, including potential legislative changes, the availability of RINs for purchase, the demand for RINs, which is dependent on transportation fuel production levels, the mix of the petroleum business'business’ petroleum products and fuel blending performed at the refineries and downstream terminals, all of which can vary significantly from period to period. In July 2017,addition, demand for RINs can be impacted by the EPA proposed certain reductions inability of refineries to obtain small refinery exemptions, or SREs, through the statutory volume targets for advanced biofuel and total renewable fuel for 2018, and requested comment on further reductions based on various considerations. On November 30, 2017, the EPA promulgated its 2018 RFS, which included renewable fuel obligations, or RVOs, that were very similar to the Agency’s original proposed mandates released in July 2017.  In establishing the 2018 RVOs, the EPA exercised its waiver authority to lower the volume requirements for cellulosic and advanced biofuel below the levels that Congress established when it first enacted the RFS in 2007. On November 30, 2018, the EPA released a final rule to set 2019 RVOs under the RFS, which includes increases to the requirement for biofuels in 2019.EPA.  Any reductions or limitations on the requirement to blend renewable fuel, including a reduction associated with the economic slowdown associated with the COVID-19 pandemic, and any related waivers including SREs, would likely reduce the volumedemand for RINs, which could impact the value of RINs.

In Canada, the Renewable Fuels Regulations under the Canadian Environmental Protection Act, 1999 require producers and importers of gasoline, diesel fuel and heating distillate to acquire a certain number of renewable fuel compliance units, or Compliance Units, in connection with the volumes of fuel they produce or import. Compliance Units can be generated in a number of ways, including through the blending of renewable fuel into liquid petroleum fuels. In some cases, landfill gas generated at our landfills in Canada qualifies as a renewable fuel that can be sold by our Company to blenders or refiners for the purpose of creating Compliance Units. Certain provincial jurisdictions in Canada also impose obligations to incorporate renewable fuels into fuels that are distributed within the jurisdiction. The price for our renewable fuel in Canada is dependent on a variety of factors, including demand. The Canadian federal government released details on a proposed new clean fuel regulatory framework at the end of 2017 called the “Clean Fuel Standard.” The proposed framework would impose lifecycle carbon intensity requirements on certain liquid, gaseous and solid fuels that are used in transportation, industry and buildings, and establish rules relating to the trading of compliance credits. The carbon intensity requirements would become more stringent over time. Carbon intensity would be differentiated between different types of renewable fuels to reflect the associated emissions reduction potential. Regulated parties, which may include fuel producers and importers, would have some flexibility with respect to how to achieve lower carbon fuels in Canada. The Canadian federal government has indicated that over time, the new Clean Fuel Standard would replace the current Renewable Fuels Regulations. Since January 2017, the Canadian federal government has been conducting public consultation on the proposed framework with final regulations anticipated in 2020 and 2021.  At this time, we do not know how athe new clean fuel regulatory frameworkClean Fuel Regulations in Canada, couldas discussed above, will impact the demand for our renewable fuel.fuel in the future.

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A significant reduction in the value of RINs in the United States or the price paid for our renewable fuel in Canada could adversely impact our reported results.

Increases in the price of diesel or compressed natural gas fuel may adversely affect our collection business and reduce our operating margins. 

The market price of diesel fuel is volatile.  We generally purchase diesel fuel at market prices, and such prices have fluctuated significantly in recent years.  A significant increase in market prices for fuel could adversely affect our waste collection business through a combination of higher fuel and disposal-related transportation costs and reduce our operating margins and reported earnings.  To manage a portion of this risk, we have entered into fixed-price fuel purchase contracts.  During periods of falling diesel fuel prices, it may become more expensive to purchase fuel under fixed-price fuel purchase contracts than at market prices. 

We utilize compressed natural gas, or CNG, in a small percentage of our fleet and we may convert more of our fleet from diesel fuel to CNG over time. The market price of CNG is also volatile; a significant increase in such cost could adversely affect our operating margins and reported earnings.

Our financial results are based upon estimates and assumptions that may differ from actual results. 

In preparing our consolidated financial statements in accordance with U.S. generally accepted accounting principles, estimates and assumptions are made that affect the accounting for and recognition of assets, liabilities, revenues and expenses.  These estimates and assumptions must be made because certain information that is used in the preparation of our financial statements is dependent on future events, cannot be calculated with a high degree of precision from data available or is not capable of being readily calculated based on generally accepted methodologies.  In some cases, these estimates are particularly difficult to determine and we must exercise significant judgment.  The most difficult, subjective and complex estimates and the assumptions that deal with the greatest amount of uncertainty are related to our accounting for landfills, self-insurance accruals, income taxes, allocation of acquisition purchase price, asset impairments and litigation, claims and assessments.  Actual results for all estimates could differ materially from the estimates and assumptions that we use, which could have an adverse effect on our financial condition and results of operations. 

Our accruals for our landfill site closure and post-closure costs may be inadequate. 

We are required to pay capping, closure and post-closure maintenance costs for landfill sites that we own and operate.  We are also required to pay capping, closure and post-closure maintenance costs for operated landfills for which we have life-of-site agreements.  Our obligations to pay closure or post-closure costs may exceed the amount we have accrued and reserved and other amounts available from funds or reserves established to pay such costs.  In addition, the completion or closure of a landfill site does not end our environmental obligations.  After completion or closure of a landfill site, there exists the potential for unforeseen environmental problems to occur that could result in substantial remediation costs or potential litigation.  Paying additional amounts for closure or post-closure costs and/or for environmental remediation and/or for litigation could harm our financial condition or operating results.

Increases in insurance costs and the amount that we self-insure for various risks could reduce our operating margins and reported earnings.

We maintain insurance policies for automobile, general, employer’s, environmental, cyber, employment practices and directors’ and officers’ liability as well as for employee group health insurance, property insurance and workers’ compensation. We carry umbrella policies for certain types of claims to provide excess coverage over the underlying policies and per incident deductibles or self-insured retentions. The amounts that we effectively self-insure could cause significant volatility in our operating margins and reported earnings based on the event and claim costs of incidents, accidents, injuries and adverse judgments. Our insurance accruals are based on claims filed and estimates of claims incurred but not reported and are developed by our management with assistance from our third-party actuary and our third-party claims administrator. To the extent these estimates are inaccurate, we may recognize substantial additional expenses in future periods that would reduce operating margins and reported earnings. Furthermore, while we maintain liability insurance, our insurance is subject to coverage limitations. If we were to incur substantial liability on a covered claim, our insurance coverage may be inadequate to cover the entirety of such liability. This could have a material adverse effect on our financial position, results of operations and cash flows. One form of coverage limitation concerns claims for punitive damages, which are generally excluded from coverage under all of our liability insurance policies. A punitive damage award could have an adverse effect on our reported earnings in the period in which it occurs. Significant increases in premiums on insurance that we retain, alsoas well as higher deductibles or self-insured retentions, could reduce our margins.

Increases in the price of diesel or compressed natural gas fuel may adversely affect our collection business and reduce our operating margins.

The market price of diesel fuel is volatile. We generally purchase diesel fuel at market prices, and such prices have fluctuated significantly in recent years. A significant increase in market prices for fuel could adversely affect our waste collection business through a combination of higher fuel and disposal-related transportation costs and reduce our operating margins and reported earnings. To manage a portion of this risk, we have entered into fixed-price fuel purchase contracts. During periods of falling diesel fuel prices, it may become more expensive to purchase fuel under fixed-price fuel purchase contracts than at market prices as the prices under our fixed-price fuel purchase contracts may be above market prices.

We utilize compressed natural gas, or CNG, in a small percentage of our fleet and we may convert more of our fleet from diesel fuel to CNG over time. The market price of CNG is also volatile; a significant increase in such cost could adversely affect our operating margins and reported earnings.

Our accruals for our landfill site closure and post-closure costs may be inadequate.

We are required to pay capping, closure and post-closure maintenance costs for landfill sites that we own and operate as well as for landfills we operated under life-of-site agreements. Our obligations to pay closure or post-closure costs may exceed the amount we have accrued and reserved and other amounts available from funds or reserves established to pay such costs. In addition, the completion or closure of a landfill site does not end our environmental obligations. After completion or closure of a landfill site, there exists the potential for unforeseen environmental problems to occur that could result in substantial remediation costs or potential litigation. The potential increased regulation of per- and polyfluoroalkyl substances (“PFAS”) and other emerging contaminants could result in greater expenditures for post-closure costs. It is also possible that accruals may need to be expanded and that costs incurred related to these activities could be accelerated. Paying additional amounts for closure or post-closure costs and/or for environmental remediation and/or for litigation could harm our financial condition, operating results, or cash flow.

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We may be subject in the normal course of business to judicial, administrative or other third-party proceedings that could interrupt or limit our operations, require expensive remediation, result in adverse judgments, settlements or fines and create negative publicity.

Governmental agencies may, among other things, impose fines or penalties on us relating to the conduct of our business, attempt to revoke or deny renewal of our operating permits, franchises or licenses for violations or alleged violations of environmental laws or regulations or as a result of third-party challenges, require us to install additional pollution control equipment or require us to remediate potential environmental problems relating to any real property that we or our predecessors ever owned, leased or operated or any waste that we or our predecessors ever collected, transported, disposed of or stored. Individuals, citizens groups, trade associations or environmental activists may also bring actions against us in connection with our operations that could interrupt or limit the scope of our business. Any adverse outcome in such proceedings could harm our operations and financial results and create negative publicity, which could damage our reputation, competitive position and share price.

Pending or future litigation or governmental proceedings could result in material adverse consequences, including judgments or settlements.

We are, and from time to time become, involved in lawsuits, regulatory inquiries, and governmental and other legal proceedings arising out of the ordinary course of our business. Many of these matters raise complicated factual and legal issues and are subject to uncertainties and complexities, all of which make the matters costly to address. For example, in recent years, wage and employment laws have changed regularly and become increasingly complex, which has fostered litigation, including purported class actions. Similarly, purported class actions based on public or private nuisance and negligence claims related to alleged landfill odor concerns have proliferated, as have citizen suits brought pursuant to environmental laws, such as those regulating the treatment of storm water runoff, have proliferated.runoff. The timing of the final resolutions to lawsuits, regulatory inquiries, and governmental and other legal proceedings is uncertain. Additionally, the possible outcomes or resolutions to these matters could include adverse judgments or settlements, either of which could require substantial payments, adversely affecting our consolidated financial condition, results of operations and cash flows. See discussion in Note 10,12, “Commitments and Contingencies,” of our consolidated financial statements included in Item 8 of this Annual Report on Form 10-K.

Our financial results could be adversely affected by impairments of goodwill, indefinite-lived intangibles or property and equipment.

As a result of our acquisition strategy, we have a material amount of goodwill, indefinite-lived intangibles and property and equipment recorded in our financial statements. We do not amortize our existing goodwill or indefinite-lived intangibles and are required to test goodwill and indefinite-lived intangibles for impairment annually in the fourth quarter of the year and whenever events or changes in circumstances indicate that the carrying value of goodwill and/or indefinite-lived intangible assets may not be recoverable using the one-step process prescribed in the new accounting guidance that we early adopted on January 1, 2017.guidance. The process screens for and measures the amount of the impairment, if any. The recoverability of property and equipment is tested for impairment whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. Application of the impairment test requires judgment. A significant deterioration in a key estimate or assumption or a less significant deterioration to a combination of assumptions could result in an additional impairment charge in the future, which could have a significant adverse impact on our reported results. See the section Goodwill and Indefinite-Lived Intangible Assets in Note 1, “Organization, Business and Summary3, “Summary of Significant Accounting Policies”Policies,” of our consolidated financial statements included in Item 8 of this Annual Report on Form 10-K.

Income taxes may be uncertain.

Our actual effective tax rate may vary from10-K regarding the impairment charge recorded during the year ended December 31, 2020 on property and equipment in our expectation and that variance may be material. Tax interpretations, regulations and legislationE&P operations due to recent declines in the various jurisdictions in which we and our affiliates operate are subject to measurement uncertainty and the interpretations can impact net income, income tax expense or recovery, and deferred income tax assets or liabilities. In addition, tax rules and regulations, including those relating to foreign jurisdictions, are subject to interpretation and require judgment by us that may be challenged by the taxation authorities upon audit.value of crude oil.  

On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act, or the Tax Act. The Tax Act makes broad and complex changes to the U.S. tax code, including, but not limited to, a reduction of the U.S. federal corporate income tax rate from 35 percent to 21 percent, requiring a one-time transition tax on certain unrepatriated earnings of foreign subsidiaries, the creation of the base erosion anti-abuse tax, a new provision designed to tax global intangible low-taxed income, a new limitation on deductible interest expense, and bonus depreciation that will allow for full expensing of qualified property.

Changes in our tax provision or an increase to our tax liabilities, whether due to the Tax Act or interpretations of the Tax Act, which include, but are not limited to, the potential finalization of proposed regulations released by the U.S. Department of Treasury during 2018 under Internal Revenue Code (“I.R.C.”) section 163(j) related to the deductibility of certain interest, I.R.C. section 59A related to a base erosion minimum tax amount, and I.R.C. section 267A related to the deductibility of certain related-party payments, as well as other tax regulations, or a final determination of tax audits, could have a material adverse effect on our financial position, results of operations, and cash flows.

Future changes to U.S., Canadian and foreign tax laws could materially adversely affect us.

We cannot give any assurance as to what our effective tax rate will be in the future, because of, among other things, uncertainty regarding the tax policies of the jurisdictions where we operate.

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For example, the U.S. Congress, the Canadian government, the Organisation for Economic Co-operation and Development (“OECD”) and other government agencies in jurisdictions where we and our affiliates do business have had an extended focus on issues related to the taxation of multinational corporations. One example is in the area of "base erosion and profit shifting," where payments are made between affiliates from a jurisdiction with high tax rates to a jurisdiction with lower tax rates. The Organisation for Economic Co-operation and Development, or OECD, addressed fifteen specific actions as part of a comprehensive plan to create an agreed set of international rules for fighting base erosion and profit shifting that was presented in a report toIn 2019, Canada ratified the G20 finance ministers in October 2015. In November 2015, the G20 leaders endorsed such report. The Canadian government has acted on certain of the other OECD recommendations and is continuing to examine other recommendations and has reiterated its commitment to implementing the OECD’s minimum standards. On June 7, 2017, Canada and other jurisdictions (not including the United States) signed the OECD’s Multilateral Convention to Implement Tax Treaty Related Measures to Prevent Base Erosion and Profit Sharing. On June 20, 2018,Shifting, or the Canadian government introduced Bill C-82,An ActMLI, as part of the OECD/G20 initiative to implement a multilateral convention to implement tax treaty related measures to preventcounter what was perceived as base erosion and profit shiftingshifting. The MLI entered into force in Canada on December 1, 2019 and entered into effect with respect to certain of Canada’s tax treaties on January 1, 2020 for withholding taxes and will enter into effect with respect to certain other taxes (including capital gains taxes) for tax years beginning on or after June 1, 2020 (which, for us and our affiliates, in general, was January 1, 2021). Bill C-82 has hadThe MLI may enter into effect at a Second Reading and was referredlater date for certain of Canada’s tax treaties with countries that have not yet completed their domestic procedures to cause the Standing Committee on Finance on October 15, 2018.MLI to come into effect. As a result of thisthese and other changes, the tax laws in the United States, Canada, and other countries in which we and our affiliates do business could change on a prospective or retroactive basis, and any such changes could adversely affect us and our affiliates.

Each business that we acquire or have acquired may have liabilities or risks that we fail or are unable to discover, or that become more adverse to our business than we anticipated at  The MLI does not impact the time of acquisition. 

It is possible that the corporate entities or sites we have acquired, or which we may acquire in the future, have liabilities or risks in respect of former or existing operations or properties, or otherwise, which we have not been able to identify and assess through our due diligence investigations.  As a successor owner, we may be legally responsible for those liabilities that arise from businesses that we acquire.  Even if we obtain legally enforceable representations, warranties and indemnities from the sellers of such businesses, they may not cover the liabilities fully or the sellers may not have sufficient funds to perform their obligations.  Some environmental liabilities, even if we do not expressly assume them, may be imposed on us under various regulatory schemes and other applicable laws.  In addition, our insurance program may not cover such sites and will not cover liabilities associated with some environmental issues that may have existed prior to attachment of coverage.  A successful uninsured claim against us could harm our financial condition or operating results. Additionally, there may be other risks of which we are unaware that could have an adverse effect on businesses that we acquire or have acquired, such as foreign, state and local regulation and administrative risks.  Another example of risk is interested parties that may bring actions against us in connection with operations that we acquire or have acquired.  Furthermore, risks or liabilities we judge to be not material or remote at the time of acquisition may develop into more serious risks to our business. Any adverse outcome resulting from such risks or liabilities could harm our operations and financial results and create negative publicity, which could damage our reputation, competitive position and share price.  For example, see the discussions regarding the Lower Duwamish Waterway Superfund Site Allocation Processtax treaty between Canada and the Florida Default Judgment in Note 10, “Commitments and Contingencies,” of our consolidated financial statements included in Item 8 of this Annual Report on Form 10-K.U.S.

Our indebtedness could adversely affect our financial condition and limit our financial flexibility.

As of December 31, 2018,2020, we had approximately $4.175$4.751 billion of total indebtedness outstanding, and we may incur additional debt in the future. This amount of indebtedness could:

In addition, a portion of our indebtedness, including interest rate swaps, is at variable rates which are based on the London Interbank Offered Rate, or LIBOR, which is expected to no longer be published after 2021. The FASB added the Secured Overnight Financing Rate, or SOFR, as an eligible benchmark interest rate in order to facilitate the LIBOR to SOFR transition and provide sufficient lead time for entities to prepare for changes to interest rate risk hedging strategies for both risk management and hedge accounting purposes. We are developing a plan to transition our indebtedness from LIBOR to SOFR.

Further, our outstanding indebtedness is subject to financial and other covenants, which may be affected by changes in economic or business conditions or other events that are beyond our control.control, including the impacts from the COVID-19 pandemic.  If we fail to comply with the covenants under any of our indebtedness, we may be in default under the indebtedness, which may entitle the lenders or holders of indebtedness to accelerate the debt obligations. A default under one of our loans or debt securities could result in cross-defaults under our other indebtedness. In order to avoid defaulting on our indebtedness, we may be required to take actions such as reducing or delaying capital expenditures, reducing or eliminating dividends or share repurchases, selling assets, restructuring or refinancing all or part of our existing debt, or seeking additional equity capital, any of which may not be available on terms that are favorable to us, if at all.

We may be unable to obtain performance or surety bonds, letters of credit or other financial assurances or to maintain adequate insurance coverage.

coverage.

If we are unable to obtain performance or surety bonds, letters of credit or insurance, we may not be able to enter into additional solid waste or other collection contracts or retain necessary landfill operating permits. Collection contracts,

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municipal contracts, transfer station operations and landfill closure and post-closure obligations may require performance or surety bonds, letters of credit or other financial assurance to secure contractual performance or comply with federal, state, provincial or local environmental laws or regulations. We typically satisfy these requirements by posting bonds or letters of credit. As of December 31, 2018,2020, we had approximately $977.6 million$1.210 billion of such surety bonds in place and approximately $125.1$126.3 million of letters of credit issued. Closure bonds are difficult and costly to obtain. If we are unable to obtain performance or surety bonds or additional letters of credit in sufficient amounts or at acceptable rates, we could be precluded from entering into additional collection contracts or obtaining or retaining landfill operating permits. Any future difficulty in obtaining insurance also could impair our ability to secure future contracts that are conditional upon the contractor having adequate insurance coverage. Accordingly, our failure to obtain performance or surety bonds, letters of credit or other financial assurances or to maintain adequate insurance coverage could limit our operations or violate federal, state, provincial, or local requirements, which could have a materially adverse effect on our business, financial condition and results of operations.

Our operations in Canada expose us to exchange rate fluctuations that could adversely affect our financial performance and our reported results of operations.

operations.

Our operations in Canada are conducted primarily in Canadian dollars. Our consolidated financial statements are denominated in U.S. dollars, and to prepare those financial statements we must translate the amounts of the assets, liabilities, net sales, other revenues and expenses of our operations in Canada from Canadian dollars into U.S. dollars using exchange rates for the current period. Fluctuations in the exchange rates that are unfavorable to us, including those resulting from the impact of the COVID-19 pandemic, would have an adverse effect on our financial performance and reported results of operations.

Alternatives to landfill disposal may cause our revenues and operating results to decline.

Counties and municipalities in which we operate landfills may be required to formulate and implement comprehensive plans to reduce the volume of municipal solid waste deposited in landfills through waste planning, composting, recycling or other programs, while working to reduce the amount of waste they generate. Some state, provincial and local governments mandate diversion, recycling and waste reduction at the source and prohibit the disposal of certain types of wastes, such as yard waste, food waste and electronics, at landfills. Even where not prohibited by state, provincial or local law, some grocery stores and restaurants have chosen to divert their organic waste from landfills, while other companies have set zero-waste goals and communicated an intention to cease the disposal of any waste in landfills. Although such actions are useful to protect our environment, these actions, as well as the actions of our customers to reduce waste or seek disposal alternatives, have reduced and may in the future further reduce the volume of waste going to landfills in certain areas, which may affect our ability to operate our landfills at full capacity and could adversely affect our operating results.

Labor union activity could divert management attention and adversely affect our operating results.

From time to time, labor unions attempt to organize our employees, and these efforts are likely to continue in the future. Certain groups of our employees are represented by unions, and we have negotiated collective bargaining agreements with most of these unions. Additional groups of employees may seek union representation in the future. As a result of these activities, we may be subjected to unfair labor practice charges, grievances, complaints and other legal and administrative proceedings initiated against us by unions or federal, state or provincial labor boards, which could negatively impact our operating results. Negotiating collective bargaining agreements with these unions could divert our management’s attention, which could also adversely affect our operating results. If we are unable to negotiate acceptable collective bargaining agreements, we might have to wait through “cooling off” periods, which may be followed by work stoppages, including strikes or lock-outs. Depending on the type and duration of any such labor disruptions, our operating expenses could increase significantly, which could adversely affect our financial condition, results of operations and cash flows.

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We could face significant withdrawal liability if we withdraw from participation in one or more multiemployer pension plans in which we participate and the accrued pension benefits are not fully funded.

We participate in 1113 “multiemployer” pension plans administered by employee and union trustees. We make periodic contributions to these plans to fund pension benefits for our union employees pursuant to our various contractual obligations to do so. In the event that we withdraw from participation in or otherwise cease our contributions to one of these plans, then applicable law regarding withdrawal liability could require us to make additional contributions to the plan if the accrued benefits are not fully funded, and we would have to reflect that “withdrawal liability” as an expense in our consolidated statement of operations and as a liability on our consolidated balance sheet. Our withdrawal liability for any multiemployer plan would depend on the extent to which accrued benefits are funded. In the ordinary course of our renegotiation of collective bargaining agreements with labor unions that participate in these plans, we may decide to discontinue participation in a multiemployer plan, and in that event, we could face withdrawal liability. Some multiemployer plans in which we participate may from time to time have significant accrued benefits that are not funded. The size of our potential withdrawal liability may be affected by the level of unfunded accrued benefits, the actuarial assumptions used by the plan and the investment gains and losses experienced by the plan.

We rely on computer systems to run our business and disruptions or privacy breaches in these systems could impact our ability to service our customers and adversely affect our financial results, damage our reputation, and expose us to litigation risk.

Our businesses rely on computer systems to provide customer information, process customer transactions and provide other general information necessary to manage our businesses. We also rely on a payment card industry-compliant third party to protect our customers’ credit card information. We have an active disaster recovery plan in place that we continuously review and test. However, our computer systems are subject to damage or interruption due to cybersecurity threats, system conversions, power outages, computer or telecommunication failures, catastrophic physical events such as fires, tornadoes and hurricanes and usage errors by our employees. Given the unpredictability of the timing, nature and scope of such disruptions, we could be potentially subject to operational delays and interruptions in our ability to provide services to our customers. Any disruption caused by the unavailability of our computer systems could adversely affect our revenues or could require significant investment to fix or replace them, and, therefore, could affect our operating results.

In addition, cybersecurity attacks are evolving and include, but are not limited to, malicious software, attempts to gain unauthorized access to data and other electronic security breaches that could lead to disruptions in systems, unauthorized release of confidential or otherwise protected information and corruption of data. We are regularly the target of attempted cyber and other security threats and must continuously monitor and develop our information technology networks and infrastructure to prevent, detect, address and mitigate the risk of unauthorized access, misuse, computer viruses and other events that could have a security impact.

Further, as we pursue our acquisition growth strategy and pursue new initiatives that improve our operations and reduce our costs, we are also expanding and improving our information technologies, resulting in a larger technological presence and corresponding exposure to cybersecurity risk. If we fail to assess and identify cybersecurity risks associated with acquisitions and new initiatives, we may become increasingly vulnerable to such risks. Additionally, while we have implemented measures to prevent security breaches and cyber incidents, our preventative measures and incident response efforts may not be entirely effective. If our network of security controls, policy enforcement mechanisms or monitoring systems we use to address these threats to technology fail, the theft or compromise of confidential or otherwise protected company, customer or employee information, destruction or corruption of data, security breaches or other manipulation or improper use of our systems and networks could result in financial losses from remedial actions, business disruption, loss of business or potential liability, liabilities due to the violation of privacy laws and other legal actions, and damage to our reputation.

Extensive and evolving environmental, health and safety laws and regulations may restrict our operations and growth and increase our costs.

Existing environmental laws and regulations have become more stringently enforced in recent years. Further, with a new federal administration taking office in 2021 in the United States, it is possible that policies and initiatives of the prior administration could be reconsidered or even reversed, which could adversely affect our operating results. For example, a

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policy shift away from curtailment of regulation, narrowing Clean Water Act jurisdiction, or enabling oil and gas development on federal lands could adversely affect our business and our customers’ business. In addition, our industry is subject to regular enactment of new or amended federal, state, provincial and local environmental and health and safety statutes, regulations and ballot initiatives, as well as judicial decisions interpreting these requirements, which have become more stringent over time. Citizen suits brought pursuant to environmental laws as well as purported class actions based on public or private nuisance and negligence claims related to alleged landfill odor concerns have proliferated.proliferated, along with the use of social media to drive such efforts. In addition, various state, provincial and local governments and the Canadian federal government have enacted, have the authority to enact or are considering enacting laws and regulations that restrict disposal within their jurisdictions of solid waste generated outside their jurisdictions. We expect these trends to continue, which could lead to material increases in our costs for future environmental, health and safety compliance. These requirements also impose substantial capital and operating costs and operational limitations on us and may adversely affect our business. In addition, federal, state, provincial and local governments may change the rights they grant to, the restrictions they impose on or the laws and regulations they enforce against, solid waste and E&P waste services companies. These changes could adversely affect our operations in various ways, including without limitation, by restricting the way in which we manage storm water runoff, comply with health and safety laws, treat and dispose of E&P or other waste or our ability to operate and expand our business.

Governmental authorities and various interest groups in the United States and Canada have promoted laws and regulations designed to limit greenhouse gas, or GHG, emissions in response to growing concerns regarding climate change. For example, the State of California, the Canadian federal government and several Canadian provinces have enacted climate change laws, and other states and provinces in which we operate are considering similar actions. The US EPA made an endangerment finding in 2009 allowing certain GHGs to be regulated under the CAA. This finding allows the EPA to create regulations that will impact our operations – including imposing emission reporting, permitting, control technology installation and monitoring requirements, although the materiality of the impacts will not be known until all applicable regulations are promulgated and finalized. The Canadian federal government enacted the Greenhouse Gas Pollution Pricing Act in June 2018, which establishesestablished a national carbon-pricing regime for the beginning ofstarting in 2019 for provinces and territories in Canada where there is no provincial systemregime in place already or where the provincial systemregime does not meet the federal benchmark. Often referred to as the federal backstop, the new federal carbon-pricing regime consists of a carbon levy that will beis applied to fossil fuels and an output-based pricing system (“OBPS”) that will beis applied to certain industrial facilities with reported emissions of 50,000 tonnes of carbon dioxide equivalent (“CO2e”) or more per year. The carbon levy will applyapplies to prescribed liquid, gaseous, and solid fuels at a rate that is equivalent to $10$30 per tonne of CO2e in 2018,2020, increasing annually, until it reaches $50 per tonne of CO2e by 2022. On November 19, 2020, the federal government introduced Bill C-12, the Canadian Net-Zero Emissions Accountability Act, which establishes the framework for national GHG emissions reduction targets to attain net-zero emissions by 2050.  Several Canadian provinces have promulgated legislation and regulations to limit GHG emissions through requirements of specific controls, carbon levies, cap and trade programs or other measures. Comprehensive GHG legislation or regulation, including carbon pricing, will affectaffects not only our business, but also that of our customers.

Regulation of GHG emissions from oil and natural gas E&P operations may also increase the costs to our customers of developing and producing hydrocarbons, and as a result, may have an indirect and adverse effect on the amount of oilfield waste delivered to our facilities by our customers. These statutes and regulations increase the costs of our operations, and future climate change statutes and regulations may have an impact as well.

Further, governmental authorities have considered or have begun to implement increased regulation of PFAS and potentially other emerging contaminants, which could adversely affect our operations. The regulation of these substances could increase or accelerate our financial obligations associated with post-closure maintenance and other environmental remediation related to our solid waste facilities. Further, enhanced treatment of landfill leachate and landfill gas could adversely affect our operations in various ways, including without limitation, increased operational expenses as well as treatment and disposal costs, greater capital expenditures to meet control requirements, costs of compliance with health and safety requirements, and litigation risk.

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Our business is subject to operational and safety risks, including the risk of personal injury to employees and others.

others.

Providing environmental and waste management services, including constructing and operating landfills, involves risks such as truck accidents, equipment defects, malfunctions and failures.  We are also an essential services provider, and our frontline employees have continued to provide services during the COVID-19 pandemic amid related mandatory and voluntary closures, shelter-in-place orders, and similar government restrictions on or advisories with respect to travel, business operations and public gatherings, which could involve additional risks.  Additionally, we closely monitor and manage landfills to minimize the risk of waste mass instability and releases of hazardous materials or odors that could be triggered by weather or natural disasters.  There may also be risks presented by the potential for subsurface chemical reactions causing elevated landfill temperatures.

We also build and operate natural gas fueling stations, some of which also serve the public or third parties. Operation of fueling stations and landfill gas collection and control systems involves additional risks of fire and explosion. Any of these risks could potentially result in injury or death of employees and others, a need to shut down or reduce operation of facilities, increased operating expense and exposure to liability for pollution and other environmental damage, and property damage or destruction.

While we seek to minimize our exposure to such risks through comprehensive training, compliance and response and recovery programs, as well as vehicle and equipment maintenance programs and the use of personal protective equipment, if we were to incur substantial liabilities in excess of any applicable insurance coverage, our business, results of operations and financial condition could be adversely affected.  Any such incidents could also tarnish our reputation and reduce the value of our brand.  Additionally, a major operational failure, even if suffered by a competitor, may bring enhanced scrutiny and regulation of our industry, with a corresponding increase in operating expense.

Future changes in laws regulating the flow of solid waste in interstate commerce could adversely affect our operating results. 

Various state, provincial and local governments and the Canadian federal government have enacted, have the authority to enact or are considering enacting laws and regulations that restrict disposal within the jurisdiction of solid waste generated outside the jurisdiction. In addition, some state, provincial and local governments and the Canadian federal government have promulgated, have the authority to promulgate or are considering promulgating laws and regulations which govern the flow of waste generated within their respective jurisdictions.  These “flow control” laws and regulations typically require that waste generated within the jurisdiction be retained within the jurisdiction or be directed to specified facilities for disposal or processing, which could limit or prohibit the disposal or processing of waste in our transfer stations and landfills or require notices be delivered or permits to be obtained prior to transport or final disposal. Certain of these flow control laws and regulations could also require us to deliver waste we collect within a particular jurisdiction to facilities not owned or controlled by us, which could increase our costs and reduce our revenues. In addition, such laws and regulations could require us to obtain additional costly licenses or authorizations in order to be deemed an authorized hauler or disposal facility. All such waste disposal laws and regulations are subject to judicial interpretation and review.  Court decisions, legislation and federal, state, provincial and local regulation in the waste disposal area could adversely affect our operations.

Extensive regulations that govern the design, operation, expansion and closure of landfills may restrict our landfill operations or increase our costs of operating landfills.

If we fail to comply with federal, state and provincial regulations, as applicable, governing the design, operation, expansion, closure and financial assurance of MSW, non-MSW and E&P waste landfills, we could be required to undertake investigatory or remedial activities, curtail operations or close such landfills temporarily or permanently. Future changes to these regulations, including an increased regulation of PFAS, may require us to modify, supplement or replace equipment or facilities at substantial costs.

If regulatory agencies fail to enforce these regulations vigorously or consistently, our competitors whose facilities are not forced to comply with the regulations may obtain an advantage over us. Our financial obligations arising from any failure to comply with these regulations could harm our business and operating results.

Our E&P waste business could be adversely affected by changes in laws regulating E&P waste.

We believe that the demand for our E&P waste services is directly related to the regulation of E&P waste. In particular, the U.S. Resource Conservation and Recovery Act, or RCRA, which governs the disposal of solid and hazardous waste, currently exempts certain E&P wastes from classification as hazardous wastes. In recent years, proposals have been made to rescind this exemption from RCRA. If the exemption covering E&P wastes is repealed or modified, or if the regulations interpreting the rules regarding the treatment or disposal of this type of waste were changed, our operations could face significantly more stringent regulations, permitting requirements, and other restrictions, which could have a material adverse effect on our business.

In addition, if new federal, state, provincial or local laws or regulations that significantly restrict hydraulic fracturing are adopted, such legal requirements could result in delays, eliminate certain drilling and injection activities and make it more difficult or costly for our customers to perform fracturing. Any such regulations limiting or prohibiting hydraulic fracturing could reduce our customers’ oil and natural gas E&P activities and, therefore, adversely affect our business. Such laws or regulations could also materially increase our costs of compliance and doing business by more strictly regulating how hydraulic fracturing wastes are handled or disposed. Conversely, any loosening of existing federal, state, provincial or local laws or regulations regarding how such wastes are handled or disposed could adversely impact demand for our services.

Liabilities for environmental damage may adversely affect our financial condition, business and earnings.

We may be liable for any environmental damage that our current or former operations cause, including damage to neighboring landowners or residents, particularly as a result of the contamination of soil, groundwater or surface water, and especially drinking water, or to natural resources. We may be liable for damage resulting from conditions existing before we acquired these operations. Even if we obtain legally enforceable representations, warranties and indemnities from the sellers of these operations, they may not cover the liabilities fully or the sellers may not have sufficient funds to perform their obligations.

We may also be liable for any on-site environmental contamination caused by pollutants or hazardous substances whose transportation, treatment or disposal we or our predecessors arranged or conducted. Some environmental laws and regulations may impose strict, joint and several liability in connection with releases of regulated substances into the environment. New or increased regulation of substances, such as PFAS or other emerging contaminants, could also lead to increased or previously unauthorized remediation costs or litigation risk.  Therefore, in some situations we could be exposed to liability as a result of our conduct that was lawful at the time it occurred or the conduct of, or conditions caused by, third parties, including our predecessors. If we were to incur liability for environmental damage, environmental clean-ups, corrective action or damage not covered by insurance or in excess of the amount of our coverage, our financial

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condition or operating results could be materially adversely affected. For example, see the discussion regarding the Lower Duwamish Waterway Superfund Site Allocation Process in Note 10,12, “Commitments and Contingencies,” of our consolidated financial statements included in Item 8 of this Annual Report on Form 10-K.

We depend significantly on the services of the members of our senior and regional management team, and the departure of any of those persons could cause our operating results to suffer.

Our success depends significantly on the continued individual and collective contributions of our senior and regional management team. Of particular importance to our success are the services of our founder, Chief Executive Officer and Chairman, Ronald J. Mittelstaedt.  Key members of our management including Mr. Mittelstaedt, have entered into employment agreements, but we may not be able to enforce these agreements. The loss of the services of any member of our senior and regional management, including as a result of the COVID-19 pandemic, or the inability to hire and retain experienced management personnel could harm our operating results.

Our decentralized decision-making structure could allow local managers to make decisions that may adversely affect our operating results.

We manage our operations on a decentralized basis. Local managers have the authority to make many decisions concerning their operations without obtaining prior approval from executive officers, subject to compliance with general company-wide policies. Poor decisions by local managers could result in the loss of customers or increases in costs, in either case adversely affecting operating results.

If we are not able to develop and protect intellectual property, or if a competitor develops or obtains exclusive rights to a breakthrough technology, our financial results may suffer.

Our existing and proposed service offerings to customers may require that we develop or license, and protect, new technologies. We may experience difficulties or delays in the research, development, production and/or marketing of new products and services which may negatively impact our operating results and prevent us from recouping or realizing a return on the investments required to bring new products and services to market. Further, protecting our intellectual property rights and combating unlicensed copying and use of intellectual property is difficult, and any inability to obtain or protect new technologies could impact our services to customers and development of new revenue sources. Additionally, a competitor may develop or obtain exclusive rights to a “breakthrough technology” that claims to provide a revolutionary change in traditional waste management. If we have inferior intellectual property to our competitors, our financial results may suffer.

General Risk Factors