Arq, Inc. (ARQ)

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are an environmental technology company and are principally engaged in the sale of consumable air, water, and soil treatment solutions primarily based on AC. Our proprietary AC products enable customers to reduce air, soil, and water contaminants, including mercury, PFAS and other pollutants to meet the challenges of existing and pending air quality, soil, and water regulations. We manufacture and sell AC and other chemicals used to capture and remove impurities, contaminants and pollutants for the coal-fired power generation, industrial, water treatment, and water and soil remediation markets, which we collectively refer to as the APT market.

Our primary products are comprised of AC, which is produced from a variety of carbonaceous raw materials. Our AC products include both PAC and GAC, among others. Additionally, we own the Five Forks Mine, a lignite coal mine that currently supplies the primary raw material for the manufacturing of our products.

In February 2023, we acquired 100% of the equity interests, assets and liabilities of the subsidiaries of Arq Limited, an environmental technology company incorporated under the laws of Jersey (hereafter the Arq Limited subsidiaries referred to as "Legacy Arq", and the acquisition itself referred to as the "Arq Acquisition") to secure access to additional U.S. based bituminous coal feedstock, a manufacturing facility located in Corbin, Kentucky (the "Corbin Facility") and certain patented processes as a means to manufacture new advanced GAC products for sale into the APT and other markets. Under this manufacturing process, we convert high-quality recovered bituminous coal fines into a purified, microfine carbon powder known as Arq powderTM ("Arq Powder") for high value applications, such as for a raw material to produce GAC products. We expect to begin using Arq Powder as a feedstock to produce high-quality GAC products by the end of the first quarter of 2025 for sale into the APT and other markets. We anticipate that our GAC products made using these highly purified recovered bituminous coal fines will have a materially lower carbon footprint than other coal-based competitor alternatives.

We believe Arq Powder has additional potential to enable us to access new markets and applications. We intend to secure customer interest in Arq Powder as an additive into other markets, such as components for asphalt. These products utilizing Arq Powder are expected to have a lower carbon footprint compared to similar products utilizing conventional materials and have demonstrated other beneficial performance attributes during lab-scale customer testing. These applications are currently in various stages of proof of concept testing or preliminary customer testing.

In February 2024, as part of a larger rebranding, the Company changed its name to Arq, Inc., and on February 1, 2024, our common stock commenced trading on the Nasdaq Global Market under the ticker symbol, "ARQ."

Drivers of Demand and Key Factors Affecting Profitability

Drivers of demand and current key factors affecting our profitability are sales of our AC products to the APT market. Our operating results are influenced by: (1) changes in our manufacturing production and sales volumes; (2) changes in price and product mix; (3) changes in coal-fired dispatch and electricity power generation sources; (4) changes in demand for contaminant removal within water treatment facilities; (5) changes in environmental regulations; and (6) state or municipal approval and customer acceptance for our new GAC products.

Components of Revenue, Expenses and Equity Method Investees

The following narrative briefly describes the components of revenue and expenses as presented in the Consolidated Statements of Operations. Descriptions of the revenue recognition policies are included in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report.

Revenue and cost of revenue

Revenue

Our revenue is comprised of the sale of AC products and other chemical-based technology products into the APT market, as well as the sale of other AC products to our largest customer, who services other diverse markets.

Cost of revenue

Cost of revenue is comprised of all labor, fringe benefits, subcontract labor, additive and coal costs, materials, equipment, supplies, travel costs and any other costs and expenses directly related to the cost of production of consumables.

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License Royalties Payable to Tinuum Group

In December 2022, the Company and Tinuum Group entered into an agreement (the "Tinuum Group Royalty Agreement") whereby we pay Tinuum Group a royalty (the "Tinuum Group Royalty") for certain of our sales of M-ProveTM products after the expiration of the tax credit program under IRC Section 45 ("Section 45 Tax Credit Program") (beginning January 1, 2022) to certain refined coal production facilities owned and operated by Tinuum Group (the "Refined Coal Facilities"). The Tinuum Group Royalty is calculated based on "Net Profit" (as defined in the Tinuum Royalty Agreement) on our sales of M-ProveTM product to certain of the Refined Coal Facilities. The Tinuum Group Royalty Agreement is for an initial term of five years with automatic renewals of five years unless we and Tinuum Group agree to terminate it. The Tinuum Group Royalty is included in Consumables cost of revenue.

Other Operating Expenses

Selling, general and administrative

Selling, general and administrative costs include payroll and benefits costs, legal and professional fees, and general and administrative expenses.

Payroll and benefits costs include payroll costs, payroll-related fringe benefits and stock-based compensation expense of sales and administrative personnel, but exclude such costs related to direct labor that are included in Cost of revenue. Payroll costs, payroll-related fringe benefits, and stock-based compensation expense of research and development personnel are reported in the Research and development line item in the Consolidated Statements of Operations.

Legal and professional costs include external legal, audit and consulting expenses.

General and administrative costs include director fees and expenses, bad debt expense, rent and occupancy expense and other general costs of conducting business.

Research and development

Research and development costs include payroll expenses related to research and development personnel and other expenses incurred related to research and development activities. Research and development costs provided by third parties, net of reimbursements from cost-sharing arrangements, are charged to expense in the period incurred.

Depreciation, amortization, depletion and accretion

Depreciation and amortization expense consists of depreciation expense related to property, plant and equipment and the amortization of long-lived intangible assets. Depletion and accretion expense consists of depletion expense related to the depletion of mine development costs and the accretion of mine reclamation liabilities.

Other (Expense) Income, net

Earnings from equity method investments

Earnings from equity method investments represent our share of earnings related to equity method investments, and in 2023 and 2024, primarily from Tinuum Group. Through December 31, 2021, we had substantial earnings from Tinuum Group and Tinuum Services, LLC ("Tinuum Services"). With the expiration of the tax credit program under IRC Section 45 afforded to producers of refined coal as of December 31, 2021, both Tinuum Group and Tinuum Services commenced winding down their operations related to the Section 45 tax credit program. We have recognized earnings in both 2023 and 2024 related to residual cash distributions received from Tinuum Group. Tinuum Services ceased operations and completed its wind down in 2024.

Other (expense) income

The remaining components of other (expense) income include interest income, interest expense and other miscellaneous items.

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Results of Operations

Presentation of Financial Results

For comparison purposes, the following tables set forth our results of operations for the years presented in the Consolidated Financial Statements included in Item 8 of this Report. The year-to-year comparison of financial results is not necessarily indicative of financial results that may be achieved in future years. This discussion and analysis compares 2024 results to 2023 results. For discussion and analysis that compares 2023 results to 2022 results, see Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations in Part II of our Annual Report on Form 10-K for the year ended December 31, 2023.

Year ended December 31, 2024 Compared to Year ended December 31, 2023

Total Revenue and Cost of Revenue

A summary of the components of revenue and cost of revenue for the years ended December 31, 2024 and 2023 is as follows:

Revenue and cost of revenue

For the years ended December 31, 2024 and 2023, revenue increased year over year primarily driven by the impact of favorable product mix of approximately $6.9 million and improved pricing for our products of approximately $4.9 million. These increases were partially offset by lower volumes sold, which negatively impacted revenue by $2.2 million. Product volumes decreased among power generation customers in 2024, primarily due to lower natural gas prices compared to 2023, which contributed to decreased utilization of coal-fired generation and decreased demand for our products. Also offsetting the overall increase was a decrease in revenue recognized from the settlement of certain contracts with customers containing minimum quantity purchases ("MQ Contracts").

Consumables gross margin, exclusive of depreciation and amortization, increased for the year ended December 31, 2024 compared to 2023. The increase in gross margin was primarily driven by an increase in revenue resulting from increased pricing of our products, while the cost to manufacture our products increased between periods, partially due to increased variable production costs on lower production volumes during 2024. Our consumables gross margin was negatively impacted by a decrease in volumes sold and lower revenue recognized from MQ Contracts in 2024 compared to 2023.

We currently expect consumables revenue to increase in the coming years as a result of increased regulatory requirements finalized by the EPA in April 2024, especially with respect to PFAS substances. However, there is substantial uncertainty regarding the future of these regulations in light of the change in the U.S. presidential administration. See "Legislation and Environmental Regulations" included in Item 1 and our risk factor discussion in Item 1A of this Report for further information.

Consumables revenue continues to be affected by electricity demand, driven by seasonal weather and related power generation needs, as well as competitor prices related to alternative power generation sources such as natural gas and renewables.

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Operating Expenses

A summary of the components of our operating expenses, exclusive of cost of revenue items (presented above), for the years ended December 31, 2024 and 2023 is as follows:

* Percent change in excess of 100% not considered meaningful.

Selling, general and administrative

A summary of the components of selling, general and administrative expenses for the years ended December 31, 2024 and 2023, exclusive of cost of revenue items (presented above), is as follows:

Payroll and benefits

Payroll and benefits expenses decreased year over year primarily due to expenses recorded during the year ended December 31, 2023 relating to severance expense of former executives, which comprised $1.7 million of the total payroll and benefit expense, and $1.1 million related to severance expense of former executives of Legacy Arq. Additionally, salaries and wages and other benefit-related expenses decreased by $1.0 million year over year primarily as a result of lower CEO compensation beginning in July 2023.

Legal and professional fees

Legal and professional fees decreased year over year primarily from decreased consulting, legal, and accounting costs incurred related to the acquisition of Legacy Arq during 2023.

General and administrative

General and administrative expenses increased year over year by approximately $2.2 million, primarily due to increases in franchise & use tax expenses, rent and occupancy expenses, outside construction-related labor and license and fee expenses, partially offset by decreases in property and liability insurance.

Research and development

Research and development expenses increased year over year primarily due to increased research and development payroll costs and conducting product qualification testing with potential lead-adopters as part of our GAC contracting process.

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Depreciation, amortization, depletion and accretion

Depreciation. amortization, depletion and accretion expense decreased by approximately $1.9 million year over year primarily due to higher absorption of depreciation into cost of goods sold during 2024 compared to 2023, which resulted in lower expense of $2.0 million for the year ended December 31, 2024, and decreased amortization of leasehold improvements, customer relationships and developed technology of $0.6 million. These decreases were partially offset by an increase in depreciation expense for property, plant and equipment acquired and placed in service during 2024.

Loss (gain) on sale of assets

For the year ended December 31, 2023, we recognized a one-time gain of $2.7 million on the sale of Marshall Mine, LLC. Loss on sale of assets was not significant for the year ended December 31, 2024.

Other (Expense) Income, net

A summary of the components of our other (expense) income, net for the years ended December 31, 2024 and 2023 is as follows:

* Percent change in excess of 100% not considered meaningful.

Earnings from equity method investments

The following table presents the equity method earnings for the years ended December 31, 2024 and 2023:

Earnings from equity method investments for the year ended December 31, 2024 represented cash distributions from Tinuum Group. Earnings from equity method investments for the year ended December 31, 2023 represented cash distributions received from both Tinuum Group and Tinuum Services. Tinuum Group continues to wind down their services into 2025. The Tinuum Group Royalty Agreement expires at the end of 2027, with an option to extend. We do not expect further distributions from Tinuum Services as Tinuum Services has completed its wind-down.

Interest expense

Interest expense increased for the year ended December 31, 2024 compared to the corresponding period in 2023 primarily due to paid in kind interest on the $10 million term loan with CF Global (the "CFG Loan"), which accrues to the principal portion and is payable upon the termination of the CFG Loan. The CFG Loan was paid in full in December 2024, and the loan agreement was terminated.

Loss on extinguishment of debt

Loss on extinguishment of debt increased year over year due to the write-off of deferred financing costs associated and unamortized debt discount with the termination of the CFG Loan.

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Other

The decrease in Other year over year is primarily driven by a decrease in interest income of $0.7 million as a result of lower cash on hand in 2024, and was driven by increased capital expenditures during 2024.

Income tax (benefit) expense

For the year ended December 31, 2024, we reported income tax benefit of $0.2 million and an effective tax rate of 3%. The difference between our reported income tax benefit and the expected federal benefit of $1.1 million, as a result of pretax loss recognized for the year ended December 31, 2024, was primarily due to an increase in the valuation allowance on our deferred tax assets offset by the benefit of permanent differences related to stock-based compensation.

For the year ended December 31, 2023, we reported income tax expense of $0.2 million and an effective rate of (1)%. The difference between our reported income tax expense and the expected federal benefit of 2.5 million, as a result of pretax loss recognized for the year ended December 31, 2024, was primarily due to the expense of permanent differences related to acquisition-related costs and an increase in the valuation allowance on our deferred tax assets.

Accounting for income taxes requires that companies assess whether a valuation allowance should be recorded against their deferred tax asset based on an assessment of the amount of the deferred tax asset that is "more likely than not" to be realized. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount that is more likely than not to be realized.

We assess a valuation allowance recorded against deferred tax assets at each reporting date. The determination of whether a valuation allowance for deferred tax assets is appropriate requires the evaluation of positive and negative evidence that can be objectively verified. Consideration must be given to all sources of taxable income available to realize the deferred tax asset, including, as applicable, the future reversal of existing temporary differences, future taxable income forecasts exclusive of the reversal of temporary differences and carryforwards, taxable income in carryback years and tax planning strategies. In estimating taxes, we assess the relative merits and risks of the appropriate tax treatment of transactions taking into account statutory, judicial, and regulatory guidance.

As of December 31, 2024, we concluded it is more likely than not we will not generate sufficient taxable income within the allowable carryforward periods to realize any of our net deferred tax assets, and fully reserved for such assets as of December 31, 2024. In reaching this conclusion, we primarily considered our pretax losses incurred over a cumulative three-year look-back period. As of December 31, 2024 and 2023, we had a valuation allowance of $101.6 million and $98.8 million, respectively, on our deferred tax assets.

The ability to recognize the remaining deferred tax assets that continue to be subject to a valuation allowance is evaluated on a quarterly basis to determine if there are any significant events that would affect the ability to utilize those deferred tax assets. Our estimate of future taxable income or losses is based on internal projections that consider historical performance, assumptions on future performance and external data. If events are identified that affect our ability to utilize our deferred tax assets, or if additional deferred tax assets are generated, we update our analysis to determine if an increase to a valuation allowance is required. Such an increase could have a material adverse effect on our financial condition and results of operations. Conversely, better than expected results and continued positive results and trends could result in a decrease to a valuation allowance, and any such decreases could have a material positive effect on our financial condition and results of operations.

See additional discussion in Note 12 of the Consolidated Financial Statements included in Item 8 of this Report.

Tax Assets

As of December 31, 2024, we had approximately $86.1 million in tax credit carryforwards. In the hypothetical event of an "ownership change," as defined by IRC Sections 382, utilization of general business credits ("Tax Credits") generated prior to the change would be subject to an annual limitation imposed by IRC Section 383 for Tax Credits. In connection with the equity offerings completed at various dates during 2024, we issued additional shares of our common stock. We performed an IRC Section 382 analysis as of those dates and determined that we had not experienced an ownership change as of those dates.

Prior to the Acquisition Date, Legacy Arq completed numerous equity offerings that resulted in ownership changes. We have not completed a formal IRC Section 382 analysis of Legacy Arq equity changes from its inception through the Acquisition Date, however, we believe that one or more "ownership changes" occurred during this time period as defined under Sections 382 and 383 and that a portion or all the Legacy Arq Tax Assets may be subject to an annual limitation.

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Non-GAAP Financial Measures

To supplement our financial information presented in accordance with U.S. Generally Accepted Accounting Principles ("GAAP"), we provide certain supplemental financial measures, including EBITDA and Adjusted EBITDA, which are measurements that are not calculated in accordance with GAAP. EBITDA is defined as earnings before interest, taxes, depreciation and amortization, and Adjusted EBITDA is defined as EBITDA reduced by the non-cash impact of equity earnings from equity method investment, loss on extinguishment of debt, loss (gain) on sale of assets, increased by cash distributions from equity method investments, loss on change in estimate, asset retirement obligations and charges incurred in as a result of our financing activities. EBITDA and Adjusted EBITDA should be considered in addition to, and not as a substitute for, net income in accordance with GAAP as a measure of performance. See below for a reconciliation from Net income, the nearest GAAP financial measure, to EBITDA and Adjusted EBITDA.

We believe that the EBITDA and Adjusted EBITDA measures are less susceptible to variances that affect our operating performance. We include these non-GAAP measures because management uses them in the evaluation of our operating performance, and believe such measures facilitate comparison of operating results between periods. We believe the non-GAAP measures provide useful information to both management and users of the financial statements by excluding certain expenses, gains, and losses which can vary widely across different industries or among companies within the same industry and may not be indicative of core operating results and business outlook.

EBITDA and Adjusted EBITDA

The following table reconciles net loss, our most directly comparable as-reported financial measure calculated in accordance with GAAP to EBITDA, Adjusted EBITDA and (Adjusted EBITDA Loss).

(1) Included in Net loss for the year ended December 31, 2023 was $4.9 million of transaction and integration costs incurred related to the Arq Acquisition, $4.9 million of Legacy Arq payroll and benefit costs and $1.7 million of severance expense related to three executive employees.

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Liquidity and Capital Resources

Current Capital Resources and Factors Affecting Our Liquidity

For the year ended December 31, 2024, our principal sources of liquidity consisted of:

•cash on hand, excluding restricted cash of $8.7 million primarily pledged as collateral under a surety bond agreement;

•cash flows from operations of $10.5 million;

•proceeds received from issuance and sale of our common stock, which totaled $42.4 million in the current year; and

•availability of $16.2 million under our recent $30.0 million secured revolving credit facility (the "Revolving Credit Facility").

For the year ended December 31, 2024, our principal uses of liquidity included:

•capital expenditures, including those related to the Red River Plant expansion and commissioning of the Corbin Facility;

•our business operating expenses;

•payments on our lease obligations; and

•payments on our debt obligations, including the extinguishment of the CFG Loan principal and accrued interest in the amount of $11.1 million.

Tinuum Group and Tinuum Services Distributions

The following table summarizes the cash distributions from our equity method investments for the years ended December 31, 2024 and 2023:

Cash distributions from Tinuum Group and Tinuum Services for 2024 decreased by $1.5 million compared to 2023, as both Tinuum Group and Tinuum Services ceased material operations as of December 31, 2021, and began wind-down of their business at that time. Tinuum Group continues to wind down their services into 2025; the Tinuum Group Royalty Agreement currently remains active through 2027 with options to extend. We do not expect further distributions from Tinuum Services as Tinuum Services has completed its wind-down.

Cash Flows

Cash and restricted cash decreased from $54.2 million as of December 31, 2023, to $22.2 million as of December 31, 2024, a decrease of $31.9 million. The following table summarizes our cash flows for the years ended December 31, 2024 and 2023, respectively:

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Cash flows from operating activities

Cash flows provided by operating activities for the year ended December 31, 2024 was $10.5 million compared to cash flows used in operating activities of $16.7 million for the year ended December 31, 2023. The increase in cash provided by operating activities was primarily due to the following: (1) a decrease in net loss of $7.1 million year over year; (2) a net increase in working capital of $17.8 million primarily as a result of significant payments made in 2023 on accounts payable and accrued expenses assumed in the Arq Acquisition, (3) a one-time $2.7 million gain on the sale of the Marshall Mine, LLC in 2023, and (4) a decrease in Earnings from equity method investments of $1.5 million. Partially offsetting the net increase in cash flows used in operating activities year over year was a decrease in Depreciation, amortization, depletion and accretion of $1.9 million.

Cash flows from investing activities

Cash flows used in investing activities for the year ended December 31, 2024 was $85.1 million compared to cash flows used in investing activities of $28.5 million for the year ended December 31, 2023. The increase in cash used was primarily due to an increase in acquisition of property, equipment and intangibles, net, of $57.7 million primarily related to capital expenditures for our Red River Plant expansion, $2.2 million cash acquired as part of the Legacy Arq Acquisition in 2023, and a decrease in distributions from equity earnings in excess of cumulative earnings of $1.5 million. Partially offsetting the net increase in cash flows used in investing activities year over year was a payment of $2.2 million related to the disposal of Marshall Mine, LLC in 2023 and a decrease in mine development costs of $2.5 million.

Cash flows from financing activities

Cash flows provided by financing activities for the year ended December 31, 2024 increased by $19.8 million compared to the year ended December 31, 2023 primarily due to proceeds from the issuance and sale of our common stock in a public offering of $26.7 million and a net increase in borrowings year over year of $5.3 million associated with a borrowing on the Revolving Credit Facility in 2024 that exceeded proceeds from the CFG Loan in 2023. These increases were offset by decreases due to the prepayment of the principal of the CFG Loan of $10.0 million in 2024 and a net decrease in proceeds from common stock issued and sold in private placements of $0.5 million year over year. Additional decreases in cash flows year over year provided by financing activities were due to costs associated with extinguishment of the CFG Loan and associated financing costs for the Revolving Credit Facility, both in 2024.

Material Cash Requirements

Our ability to continue to generate sufficient cash flow required to meet ongoing operational needs and obligations depends upon several factors. These include executing on our contracts and initiatives and increasing our share of the market for APT consumables, including expanding our overall AC business into additional adjacent markets and increasing our gross margin from improving our customer and product mix.

Based on current operating levels, we expect that our cash on hand and borrowing availability on the Revolving Credit Facility as of December 31, 2024 will provide sufficient liquidity to fund operations for the next 12 months.

Capital expenditures

We are targeting the first quarter of 2025 for the completion of our Red River Plant expansion which is necessary to commence production of our new GAC products. To meet this target, we have incurred and may continue to incur substantial capital spend in excess of our originally forecasted amount for additional equipment, labor, and project costs. The Company anticipates financing the timely completion of the project funded with cash on hand, borrowing availability on the Revolving Credit Facility, and ongoing cost reduction initiatives.

During 2025, we expect our capital expenditures to primarily relate to the completion of the Red River Project. Capital expenditures planned for 2025 are dependent on many factors, including the approval of certain environmental permits, and the pace and progression of the project, which may impact the timing and amount of capital expenditures.

Surety Bonds

As of December 31, 2024, we had outstanding surety bonds with regulatory commissions totaling $11.1 million primarily related to the Five Forks Mine and the Corbin Facility. As of December 31, 2024, and as required by our surety bond provider, we held restricted cash of $8.5 million pledged as collateral related to performance requirements required under a reclamation contract for the Five Forks Mine and the Corbin Facility. We expect that the obligations secured by these surety bonds will be performed in the ordinary course of business and in accordance with the applicable contractual terms. To the extent that the

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obligations are performed, the related surety bonds may be released and collateral requirements may be reduced. However, in the event any surety bond is called, our indemnity obligations could require us to reimburse the surety bond provider.

Long Term Requirements

For a discussion of our long-term cash requirements, see Item 8, Note 5 of this Report.

Contractual Obligations

Contractual obligations as of December 31, 2024 are as follows:

The table above excludes our asset retirement obligation ("ARO") related to reclamation of the Five Forks Mine, as the timing and amount of payments to satisfy the ARO are uncertain and are based on numerous factors including, but not limited to, the expected closure date of the Five Forks Mine. As of December 31, 2024, our Consolidated Balance Sheet reflects a liability for ARO related to reclamation of the Five Forks Mine of $4.5 million. The table above also excludes amounts outstanding under our Revolving Credit Facility, as the timing and amount of repayments are uncertain and are based on the nature and timing of our operating cash flows. Our outstanding borrowings under the Revolving Credit Facility were $13.8 million as of December 31, 2024. Additionally, the table above excludes construction costs related to the Red River Plant expansion referred to under the "Capital Expenditures" caption above, as the timing and amount of payments to satisfy these obligations are conditional and based on numerous factors including, but not limited to, the pace of construction activities and the timing of mechanical completion of the Red River Plant expansion.

Critical Accounting Policies and Estimates

Our significant accounting policies are discussed in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report. In presenting our financial statements in conformity with GAAP, we are required to make estimates and assumptions that affect the amounts reported therein. Several of the estimates and assumptions we are required to make relate to matters that are inherently uncertain as they pertain to future events. Our estimates are based on historical experience and other assumptions believed to be reasonable under the circumstances, and we evaluate these estimates on an ongoing basis. Actual results may differ from these estimates under different assumptions or conditions.

We believe that the accounting estimates discussed below are critical to understanding our historical and future performance, as these estimates relate to the more significant areas involving management’s judgments and estimates.

Business Combinations, including asset acquisitions

We apply the acquisition method to acquisitions of both businesses and assets and allocate the purchase price to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the acquisition date. The purchase price allocation process requires us to make significant estimates and assumptions with respect to assets acquired and liabilities assumed. We believe the assumptions and estimates we make are reasonable, they are based in part on historical experience, market conditions and information obtained from management of the acquired company or group of assets and are inherently uncertain.

Examples of critical estimates in valuing certain of long-lived assets, including intangible assets, we have acquired or may acquire in the future include but are not limited to:

•future expected cash flows from revenue;

•the acquired company’s developed technology as well as assumptions about the period of time the acquired developed technology will continue to be used in the combined company's product portfolio;

•the expected use and useful lives of the acquired assets; and

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•valuation methods and discount rates used in estimating the values of the assets acquired and liabilities assumed.

Carrying value of long-lived assets and intangibles

We review and evaluate our long-lived assets and intangibles for impairment at least annually, or more frequently when events or changes in circumstances indicate that the related carrying amounts may not be recoverable. An impairment loss is measured and recorded for long-lived assets and intangibles based on the excess of their carrying amounts over their estimated fair values. Fair value is typically determined through the use of an income approach utilizing estimates of discounted pretax future cash flows or a market approach utilizing recent transaction activity for comparable assets.

Asset Retirement Obligations

Accounting for AROs requires us to make estimates of future costs unique to a specific mining operation that we will incur to complete the reclamation and remediation work required to comply with existing laws and regulations. Any such changes in future costs, the timing of reclamation activities, scope or the exclusion of certain costs not considered reclamation and remediation costs could materially impact the amounts charged to earnings for reclamation and remediation. Additionally, future changes to environmental laws and regulations could increase the scope of reclamation and remediation work required.

Reclamation costs related to AROs are allocated to expense over the life of the related mine assets and are periodically adjusted to reflect changes in the estimated present value resulting from the passage of time and revisions to the estimates of either the timing or amount of the reclamation costs. Remediation costs are accrued based on management’s best estimate of the costs expected to be incurred. Such cost estimates may include ongoing care, maintenance and monitoring costs. Reclamation obligations are based on the timing of estimated spending for an existing environmental disturbance. We review, on at least an annual basis, the future expected costs and the timing of such costs for AROs.

Income Taxes

We account for income taxes under the asset and liability method, which requires judgment in determining income tax expense and the related balance sheet amounts. This includes estimating and analyzing historical and projected future operating results, the reversal of taxable temporary differences, tax planning strategies, and the ultimate outcome of uncertain income tax positions. Actual income taxes paid may vary from estimates depending on changes in income tax laws, actual results of operations, state apportionment and, if applicable, final audits of tax returns by taxing authorities. Tax assessments may arise several years after tax returns have been filed. Changes in the estimates and assumptions used for calculating income tax expense and potential differences in actual results from estimates could have a material impact on our results of operations and financial condition.

We recognize deferred tax assets to the extent that we believe these assets are more likely than not to be realized. In making such a determination, we consider all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies and results of recent operations.

We establish a valuation allowance against our deferred tax assets when, based upon the weight of all available evidence, we believe it is more likely than not that some portion or all of the deferred tax assets will not be realized. In making this determination, we consider the relative impact of all of the available positive and negative evidence regarding future sources of taxable income and tax planning strategies. However, there could be a material impact to our effective tax rate if there is a significant change in our estimates of future taxable income. If and when our estimates change, or there is a change in the value of deferred tax assets or liabilities warranting the need to reassess the realizability of deferred tax assets, we adjust a valuation allowance through the provision for income taxes in the period in which this determination is made. Refer to Note 12 of our Consolidated Financial Statements included in Item 8 of this Report for additional information regarding our deferred tax assets and liabilities.

Recently Issued Accounting Standards

Refer to Note 1 of the Consolidated Financial Statements included in Item 8 of this Report for information regarding recently issued accounting standards.

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are an environmental technology company and are principally engaged in the sale of consumable air and water treatment solutions primarily based on AC. Our proprietary AC products enable customers to reduce air, soil, and water contaminants, including mercury, PFAS and other pollutants, to help our customers maximize utilization effectiveness and to improve operating efficiencies to meet the challenges of existing and pending air quality, soil, and water regulations. We manufacture and sell AC and other chemicals used to capture and remove contaminants for coal-fired power generation, industrial and water treatment markets, which we collectively refer to as the advanced purification technologies or "APT" market.

Our primary products are comprised of AC, which is produced from a variety of carbonaceous raw materials. Our AC products include both PAC and GAC. Additionally, we own the Five Forks Mine, a lignite mine that currently supplies the primary raw material for the manufacturing of our products.

In February 2023, we acquired 100% of the equity of the subsidiaries of Arq Limited (hereafter the Arq Limited subsidiaries referred to as "Legacy Arq", and the acquisition itself referred to as the "Arq Acquisition") to secure access to a feedstock, a manufacturing facility and certain patented processes as a means to manufacture additional GAC products for sale into the APT and other markets. With the Arq Acquisition, we now control bituminous coal waste reserves and own a manufacturing facility, both located in Corbin, Kentucky (the "Corbin Facility"), and a process to recover and purify the bituminous coal fines for sale or further conversion to GAC products. Under this manufacturing process, we convert coal waste into a purified, microfine carbon powder known as Arq powderTM ("Arq Powder"). We expect to begin using Arq Powder as a feedstock to begin manufacturing GAC products by the end of 2024 to begin using Arq Powder as a feedstock to produce high-quality GAC products for sale in the APT and other markets.

We believe Arq Powder has additional potential for us to access new markets and applications. We expect to secure customer interest in Arq Powder as an additive into other markets, such as components for asphalt. These products utilizing Arq Powder are expected to have a lower carbon footprint compared to similar products utilizing conventional materials. These applications are currently in various stages of proof of concept testing or preliminary customer testing.

In February 2024, as part of a larger rebranding, the Company changed its name to Arq, Inc., and on February 1, 2024, our common stock commenced trading under the ticker symbol, "ARQ".

Drivers of Demand and Key Factors Affecting Profitability

Drivers of demand and current key factors affecting our profitability are sales of our AC products to the APT market. Our operating results are influenced by: (1) changes in our manufacturing production and sales volumes; (2) changes in price and product mix; (3) changes in coal-fired dispatch and electricity power generation sources and (4) changes in demand for contaminant removal within water treatment facilities.

Components of Revenue, Expenses and Equity Method Investees

The following briefly describes the components of revenue and expenses as presented in the Consolidated Statements of Operations. Descriptions of the revenue recognition policies are included in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report.

Revenue and cost of revenue

Consumables

Our revenue is comprised of the sale of AC products and other chemical-based technology products in the APT market, as well as the sale of other AC products to our largest customer, who services other diverse markets.

Consumables cost of revenue

Consumables cost of revenue is comprised of all labor, fringe benefits, subcontract labor, additive and coal costs, materials, equipment, supplies, travel costs and any other costs and expenses directly related to the cost of production of consumables.

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License royalties payable to Tinuum Group

In December 2022, the Company and Tinuum Group entered into an agreement (the "Tinuum Group Royalty Agreement") whereby we pay Tinuum Group a royalty (the "Tinuum Group Royalty") for certain of our sales of M-ProveTM products after the expiration of the tax credit program under IRC Section 45 ("Section 45 Tax Credit Program") (beginning January 1, 2022) to certain of the M-45 Facilities. The Tinuum Group Royalty is calculated based on "Net Profit" (as defined in the Tinuum Royalty Agreement) on our sales of M-ProveTM product to certain of the M-45 Facilities. The Tinuum Group Royalty Agreement is for an initial term of five years with automatic renewals of five years unless we and Tinuum Group agree to terminate it. The Tinuum Group Royalty is included in Consumables cost of revenue.

Other Operating Expenses

Payroll and benefits

Payroll and benefits costs include payroll costs, payroll related fringe benefits and stock based compensation expense of research and development, sales and administrative personnel, but exclude such costs related to direct labor that are included in Cost of revenue.

Legal and professional fees

Legal and professional costs include external legal, audit and consulting expenses.

General and administrative

General and administrative costs include director fees and expenses, bad debt expense, research and development expense and other general costs of conducting business. Research and development costs provided by third parties, net of reimbursements from cost-sharing arrangements, are charged to expense in the period incurred and are reported in the General and administrative line item in the Consolidated Statements of Operations.

Depreciation, amortization, depletion and accretion

Depreciation and amortization expense consists of depreciation expense related to property, plant and equipment and the amortization of long-lived intangible assets. Depletion and accretion expense consists of depletion expense related to the depletion of mine development costs and the accretion of mine reclamation liabilities.

Other Income (Expense), net

Earnings from equity method investments

Earnings from equity method investments represent our share of earnings (losses) related to equity method investments, and in 2023, primarily from Tinuum Group. Through December 31, 2021, we had substantial earnings from Tinuum Group and Tinuum Services, LLC ("Tinuum Services"). With the expiration of the tax credit program under IRC Section 45 afforded to producers of refined coal as of December 31, 2021, both Tinuum Group and Tinuum Services commenced winding down their operations related to the Section 45 tax credit program, although we have recognized earnings in both 2022 and 2023 related to residual cash distributions received.

Other income (expense)

The remaining components of other income (expense) include interest income, interest expense and other miscellaneous items.

Results of Operations

Presentation of Financial Results

For comparison purposes, the following tables set forth our results of operations for the years presented in the Consolidated Financial Statements included in Item 8 of this Report. The year-to-year comparison of financial results is not necessarily indicative of financial results that may be achieved in future years. Our Annual Report on Form 10-K for the year ended December 31, 2023 includes a discussion and analysis of our financial condition and results of operations for the year ended December 31, 2023 compared to the year ended December 31, 2022, disclosed in Item 7 of Part II, "Management’s Discussion and Analysis of Financial Condition and Results of Operations."

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Year ended December 31, 2023 Compared to Year ended December 31, 2022

Total Revenue and Cost of Revenue

A summary of the components of revenue and cost of revenue for the years ended December 31, 2023 and 2022 is as follows:

Consumables revenue and consumables cost of revenue

For the years ended December 31, 2023 and 2022, consumables revenue decreased year over year primarily driven by lower volumes sold, which comprised $20.0 million of the total change. Product volumes decreased among power generation customers, primarily due to lower natural gas prices compared to 2022, which contributed to decreased utilization of coal-fired generation and decreased demand for our products. Partially offsetting the decrease was an increase due to improved pricing for our products of approximately $10.6 million, $4.7 million of revenue recognized from the settlement of certain contracts with customers containing minimum quantity purchases ("MQ Contacts") and the impact of favorable product mix of approximately $0.7 million.

Consumables gross margin, exclusive of depreciation and amortization, increased for the year ended December 31, 2023 compared to 2022. Driving the increase in gross margin were the impact of the MQ contracts and decreased cost of our feedstock and additives, primarily as a result of decreased production volumes during 2023. Our consumables gross margin was negatively impacted by a decrease in volumes sold.

Consumables revenue continues to be affected by electricity demand, driven by seasonal weather and related power generation needs, as well as competitor prices related to alternative power generation sources such as natural gas and renewables.

Other Operating Expenses

A summary of the components of our operating expenses, exclusive of cost of revenue items (presented above), for the years ended December 31, 2023 and 2022 is as follows:

* Calculation not meaningful

Payroll and benefits

Payroll and benefits expenses increased year over year primarily due to the addition of Legacy Arq employees, which increased expenses by $4.9 million for the year, of which $1.1 million related to severance expense of former executives of Legacy Arq. In addition, for the year ended December 31, 2023, we incurred severance related costs of $1.7 million associated with the termination of three executive employees. These increases were partially offset by a decrease in incentive compensation related

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to non-Legacy Arq employees for the year ended December 31, 2023 of $1.3 million compared to the corresponding period in 2022. An additional decrease in payroll and benefits was due to retention bonuses with our executive officers and certain other key employees of $1.2 million, which were paid in full in January 2023.

Legal and professional fees

Legal and professional fees remained flat year over year.

General and administrative

General and administrative expenses increased for the year ended December 31, 2023 compared to the corresponding period in 2022 as a result of $2.5 million of expenses incurred on behalf of Legacy Arq, which included $1.2 million from rent and occupancy expense from additional leased space. Additional increases period over period of approximately $2.0 million were due to increases in insurance, research and development, travel, recruiting and other outside labor, and director compensation as three new directors were added to the board in connection with the Arq Acquisition.

Depreciation, amortization, depletion and accretion

Depreciation and amortization expense increased for the year ended December 31, 2023 compared to the corresponding period in 2022 primarily due to depreciation and amortization of approximately $2.8 million from the addition of long-lived assets and intangible assets acquired in the Arq Acquisition. Also contributing to the increase was an increase in Depreciation and amortization expense due to higher production volumes compared to sales volumes which resulted in $1.0 million additional absorption of depreciation in inventory.

Gain on sale of Marshall Mine, LLC

As discussed above, for the year ended December 31, 2023, we recognized a gain of $2.7 million on the sale of Marshall Mine, LLC.

Other Income (Expense), net

A summary of the components of our other income (expense), net for the years ended December 31, 2023 and 2022 is as follows:

Earnings from equity method investments

The following table presents the equity method earnings by investee for the years ended December 31, 2023 and 2022:

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Earnings from equity method investments for the year ended December 31, 2023 and 2022 represented cash distributions received from Tinuum Group and Tinuum Services. The decrease was primarily due to Tinuum Group and Tinuum Services continuing to wind down their operations in 2023.

Interest expense

Interest expense increased for the year ended December 31, 2023 compared to the corresponding period in 2022 primarily due to interest expense of $2.0 million related to the $10 million CFG Loan and interest expense of $0.5 million incurred for the same period related to the $10 million CTB Loan assumed by us in the Arq Acquisition.

Other

The increase in Other is primarily driven by interest income of $1.8 million generated from the use of cash sweep accounts in 2023.

Income tax expense

For the year ended December 31, 2023, our reported income tax expense was $0.2 million and was based on an effective rate of (1)%. The difference between our reported income tax expense and the expected federal benefit, as a result of pretax loss recognized for the year ended December 31, 2023, was primarily due to permanent differences related to acquisition-related costs, an increase in the valuation allowance on our deferred tax assets and stock-based compensation.

For the year ended December 31, 2022, our reported income tax expense was $0.2 million and was based on an effective rate of (2)%. The difference between our reported income tax expense and the expected federal benefit, as a result of pretax loss recognized for the year ended December 31, 2023, was primarily due to permanent differences related to acquisition-related costs and an increase in the valuation allowance on our deferred tax assets.

Accounting for income taxes requires that companies assess whether a valuation allowance should be recorded against their deferred tax asset based on an assessment of the amount of the deferred tax asset that is "more likely than not" to be realized. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount that is more likely than not to be realized.

We assess a valuation allowance recorded against deferred tax assets at each reporting date. The determination of whether a valuation allowance for deferred tax assets is appropriate requires the evaluation of positive and negative evidence that can be objectively verified. Consideration must be given to all sources of taxable income available to realize the deferred tax asset, including, as applicable, the future reversal of existing temporary differences, future taxable income forecasts exclusive of the reversal of temporary differences and carryforwards, taxable income in carryback years and tax planning strategies. In estimating taxes, we assess the relative merits and risks of the appropriate tax treatment of transactions taking into account statutory, judicial, and regulatory guidance.

As of December 31, 2023, we concluded it is more likely than not we will not generate sufficient taxable income within the allowable carryforward periods to realize any of our net deferred tax assets, and fully reserved for such assets as of December 31, 2023. In reaching this conclusion, we primarily considered forecasts of future taxable losses. As of December 31, 2023 and 2022, we had a valuation allowance of $98.8 million and $88.3 million, respectively, on our deferred tax assets.

The ability to recognize the remaining deferred tax assets that continue to be subject to a valuation allowance is evaluated on a quarterly basis to determine if there are any significant events that would affect the ability to utilize those deferred tax assets. Our estimate of future taxable income or losses is based on internal projections that consider historical performance, assumptions on future performance and external data. If events are identified that affect our ability to utilize our deferred tax assets, or if additional deferred tax assets are generated, we update our analysis to determine if an increase to a valuation allowance is required. Such an increase could have a material adverse effect on our financial condition and results of operations. Conversely, better than expected results and continued positive results and trends could result in a decrease to a valuation allowance, and any such decreases could have a material positive effect on our financial condition and results of operations.

See additional discussion in Note 13 of the Consolidated Financial Statements included in Item 8 of this Report.

Tax Assets

Through December 31, 2021, we earned substantial tax credits under the Section 45 tax credit program, which expired on December 31, 2021. As of December 31, 2023, we had approximately $86.1 million in Section 45 tax credit carryforwards.

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In the hypothetical event of an "ownership change," as defined by IRC Sections 382, utilization of general business credits ("Tax Credits") generated prior to the change would be subject to an annual limitation imposed by IRC Section 383 for Tax Credits. In connection with the Arq Acquisition and PIPE Investment, we issued additional shares of our common stock. We performed an IRC Section 382 analysis as of the Acquisition Date and determined that we had not experienced an ownership change as of that date.

Prior to the Acquisition Date, Legacy Arq completed numerous equity offerings that resulted in ownership changes. We have not completed a formal IRC Section 382 analysis of Legacy Arq equity changes from its inception through the Acquisition Date, however, we believe that one or more "ownership changes" occurred during this time period as defined under Sections 382 and 383 and that a portion or all the Legacy Arq Tax Assets may subject to an annual limitation.

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Non-GAAP Financial Measures

To supplement our financial information presented in accordance with U.S. Generally Accepted Accounting Principles ("GAAP"), we provide certain supplemental financial measures, including EBITDA and Adjusted EBITDA, which are measurements that are not calculated in accordance with U.S. Generally Accepted Accounting Principles ("GAAP"). EBITDA is defined as earnings before interest, taxes, depreciation and amortization, and Adjusted EBITDA is defined as EBITDA reduced by the non-cash impact of equity earnings from equity method investments and gain on sale of the Marshall Mine, increased by cash distributions from equity method investments, loss on early settlement of a long-term receivable and loss on change in estimate, asset retirement obligations. EBITDA and Adjusted EBITDA should be considered in addition to, and not as a substitute for, net income in accordance with GAAP as a measure of performance. See below for a reconciliation from Net income, the nearest GAAP financial measure, to EBITDA and Adjusted EBITDA.

We believe that the EBITDA and Adjusted EBITDA measures are less susceptible to variances that affect the Company's operating performance. We include these non-GAAP measures because management uses them in the evaluation of our operating performance, and believe they help to facilitate comparison of operating results between periods. We believe the non-GAAP measures provide useful information to both management and users of the financial statements by excluding certain expenses, gains, and losses which can vary widely across different industries or among companies within the same industry and may not be indicative of core operating results and business outlook.

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EBITDA and Adjusted EBITDA

The following table reconciles net loss, our most directly comparable as-reported financial measure calculated in accordance with GAAP to EBITDA, (EBITDA Loss), (Adjusted EBITDA Loss) and Adjusted EBITDA.

(1) Included in Net loss for the year ended December 31, 2023 and 2022 was $4.9 million and $5.0 million, respectively, of transaction and integration costs incurred related to the Arq Acquisition. Additionally, for the year ended December 31, 2023, Net loss included $4.9 million of Legacy Arq payroll and benefit costs and $1.7 million of severance expense related to three executive employees.

Liquidity and Capital Resources

Current Resources and Factors Affecting Our Liquidity

As of December 31, 2023, our principal future sources of liquidity included:

•cash on hand, excluding restricted cash of $8.8 million primarily pledged as collateral under a surety bond agreement; and

•our operations

For the year ended December 31, 2023, our principal uses of liquidity included:

•our business operating expenses;

•capital and spare parts expenditures;

•payments on our lease obligations;

•payments for reclamation associated with the Five Forks Mine; and

•payment required under the sale of Marshall Mine, LLC.

On February 1, 2023, in connection with the Arq Acquisition, we closed the PIPE Investment for an aggregate purchase price of $15.4 million. Further, on February 1, 2023 we entered into the CFG Loan Agreement for $10.0 million, of which we received $8.5 million net proceeds.

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Tinuum Group and Tinuum Services Distributions

The following table summarizes the cash distributions from our equity method investments for the years ended December 31, 2023 and 2022:

Cash distributions from Tinuum Group and Tinuum Services for 2023 decreased by $4.3 million compared to 2022 primarily due to Tinuum Group and Tinuum Services ceasing material operations as of December 31, 2021.

Cash Flows

Cash and restricted cash decreased from $76.4 million as of December 31, 2022, to $54.2 million as of December 31, 2023, a decrease of $22.3 million. The following table summarizes our cash flows for the years ended December 31, 2023 and 2022, respectively:

Cash flows from operating activities

Cash flows used in operating activities for the year ended December 31, 2023 was $16.7 million compared to cash flows used in operating activities of $6.1 million for the year ended December 31, 2022. The increase in cash used in operating activities was primarily due to the following: (1) an increase in net loss of $3.3 million year over year; (2) a $2.7 million gain on the sale of the Marshall Mine, LLC; (3) a decrease in Distributions from equity method investees, return on investment of $2.3 million year over year; and (4) a net decrease in working capital of $8.9 million primarily as a result of significant payments made in 2023 on accounts payable and accrued expenses assumed in the Arq Acquisition. Offsetting the net increase in cash flows used in operating activities year over year were (1) an increase in Depreciation, amortization, depletion and accretion of $4.1 million; and (2) a decrease in Earnings from equity method investments of $1.9 million.

Cash flows from investing activities

Cash flows used in investing activities for the year ended December 31, 2023 was $28.5 million compared to cash flows used in investing activities of $4.6 million for the year ended December 31, 2022. The increase was primarily due to an increase in acquisition of property, equipment and intangibles, net, of $18.6 million primarily related to acquisition costs related to the Arq Acquisition, a payment of $2.2 million related to the disposal of Marshall Mine, LLC, increased mine development costs of $2.1 million, and a decrease in distributions from equity earnings in excess of cumulative earnings of $2.0 million. Offsetting the net increase in cash flows used in investing activities year over year was $2.2 million cash acquired as part of the Arq Acquisition.

Cash flows from financing activities

Cash flows provided by (used in) financing activities for the year ended December 31, 2023 increased by $24.6 million compared to the year ended December 31, 2022 primarily due to proceeds from common stock issued of $16.2 million,

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including $1.0 million of proceeds from common stock issued to related parties, and net proceeds from the issuance of the CFG Loan Agreement of $8.5 million.

Material Cash Requirements

Our ability to continue to generate sufficient cash flow required to meet ongoing operational needs and obligations depends upon several factors. These include executing on our contracts and initiatives and increasing our share of the market for APT consumables, including expanding our overall AC business into additional adjacent markets and increasing our gross margin from improving our customer and product mix.

Based on current operating levels, we expect that our cash on hand as of December 31, 2023 will provide sufficient liquidity to fund operations for the next 12 months.

Capital expenditures

We have targeted the end of 2024 for the completion of our Red River Plant expansion that is necessary to commence production of our new GAC products. To meet this target, we will incur substantial capital spend in excess of our originally forecasted amount for additional equipment, labor, and project costs. The Company anticipates financing the timely completion of the project funded with cash on hand, cash generation, ongoing cost reduction initiatives, potential customer prepayments for GAC contracts, and a planned refinancing and potential expansion of our term loan. If we are not able to secure additional financing, the project timeline for our Red River Plant expansion may be delayed beyond the end of 2024.

During 2024, we expect to spend between $45 and $50 million on the Red River Plant expansion, depending on the pace of the project, as well as between $5 and $10 million to complete our commissioning of the Corbin Facility. Capital expenditures planned for 2024 are dependent on many factors, including the ability to raise additional funding and approval of certain environmental permits, both of which may impact the timing and amount of capital expenditures.

Surety Bonds

As of December 31, 2023, we had outstanding surety bonds with regulatory commissions totaling $11.2 million primarily related to the Five Forks Mine and the Corbin Facility. As of December 31, 2023, and as required by our surety bond provider, we held restricted cash of $8.5 million pledged as collateral related to performance requirements required under a reclamation contract for the Five Forks Mine and the Corbin Facility. We expect that the obligations secured by these surety bonds will be performed in the ordinary course of business and in accordance with the applicable contractual terms. To the extent that the obligations are performed, the related surety bonds may be released and collateral requirements may be reduced. However, in the event any surety bond is called, our indemnity obligations could require us to reimburse the surety bond provider.

Long Term Requirements

For a discussion of our long-term cash requirements, see Item 8. Note 6 of this Report.

Contractual Obligations

Contractual obligations as of December 31, 2023 are as follows:

The table above excludes our asset retirement obligation ("ARO") related to reclamation of the Five Forks Mine, as the timing and amount of payments to satisfy the ARO are uncertain and are based on numerous factors including, but not limited to, the expected closure date of the Five Forks Mine. As of December 31, 2023, our Consolidated Balance Sheet reflects a liability for AROs of $6.2 million. Additionally, the table above excludes construction costs related to the Red River Plant expansion and Corbin Facility commissioning referred to under "Capital Expenditures" caption above, as the timing and amount of payments

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to satisfy these obligations are conditional and based on numerous factors including, but not limited to, the pace of construction activities and the timing of mechanical completion of the Red River Plant expansion and commissioning activities at the Corbin Facility.

Critical Accounting Policies and Estimates

Our significant accounting policies are discussed in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report. In presenting our financial statements in conformity with GAAP, we are required to make estimates and assumptions that affect the amounts reported therein. Several of the estimates and assumptions we are required to make relate to matters that are inherently uncertain as they pertain to future events. Our estimates are based on historical experience and other assumptions believed to be reasonable under the circumstances, and we evaluate these estimates on an ongoing basis. Actual results may differ from these estimates under different assumptions or conditions.

We believe that the accounting estimates discussed below are critical to understanding our historical and future performance, as these estimates relate to the more significant areas involving management’s judgments and estimates.

Business Combinations, including asset acquisitions

We apply the acquisition method to acquisitions of both businesses and assets and allocate the purchase price to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the acquisition date. The purchase price allocation process requires us to make significant estimates and assumptions with respect to assets acquired and liabilities assumed. We believe the assumptions and estimates we make are reasonable, they are based in part on historical experience, market conditions and information obtained from management of the acquired company or group of assets and are inherently uncertain.

Examples of critical estimates in valuing certain of long-lived assets, including intangible assets, we have acquired or may acquire in the future include but are not limited to:

•future expected cash flows from revenue;

•the acquired company’s developed technology as well as assumptions about the period of time the acquired developed technology will continue to be used in the combined company's product portfolio;

•the expected use and useful lives of the acquired assets; and

•valuation methods and discount rates used in estimating the values of the assets acquired and liabilities assumed.

Carrying value of long-lived assets and intangibles

We review and evaluate our long-lived assets and intangibles for impairment at least annually, or more frequently when events or changes in circumstances indicate that the related carrying amounts may not be recoverable. An impairment loss is measured and recorded for long-lived assets and intangibles based on the excess of their carrying amounts over their estimated fair values. Fair value is typically determined through the use of an income approach utilizing estimates of discounted pretax future cash flows or a market approach utilizing recent transaction activity for comparable assets.

Asset Retirement Obligations

Accounting for AROs requires us to make estimates of future costs unique to a specific mining operation that we will incur to complete the reclamation and remediation work required to comply with existing laws and regulations. Any such changes in future costs, the timing of reclamation activities, scope or the exclusion of certain costs not considered reclamation and remediation costs could materially impact the amounts charged to earnings for reclamation and remediation. Additionally, future changes to environmental laws and regulations could increase the scope of reclamation and remediation work required.

Reclamation costs related to AROs are allocated to expense over the life of the related mine assets and are periodically adjusted to reflect changes in the estimated present value resulting from the passage of time and revisions to the estimates of either the timing or amount of the reclamation costs. Remediation costs are accrued based on management’s best estimate of the costs expected to be incurred. Such cost estimates may include ongoing care, maintenance and monitoring costs. Reclamation obligations are based on the timing of estimated spending for an existing environmental disturbance. We review, on at least an annual basis, the future expected costs and the timing of such costs for AROs.

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Income Taxes

We account for income taxes under the asset and liability method, which requires judgment in determining income tax expense and the related balance sheet amounts. This includes estimating and analyzing historical and projected future operating results, the reversal of taxable temporary differences, tax planning strategies, and the ultimate outcome of uncertain income tax positions. Actual income taxes paid may vary from estimates depending on changes in income tax laws, actual results of operations, state apportionment and, if applicable, final audits of tax returns by taxing authorities. Tax assessments may arise several years after tax returns have been filed. Changes in the estimates and assumptions used for calculating income tax expense and potential differences in actual results from estimates could have a material impact on our results of operations and financial condition.

We recognize deferred tax assets to the extent that we believe these assets are more likely than not to be realized. In making such a determination, we consider all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies and results of recent operations.

We establish a valuation allowance against our deferred tax assets when, based upon the weight of all available evidence, we believe it is more likely than not that some portion or all of the deferred tax assets will not be realized. In making this determination, we consider the relative impact of all of the available positive and negative evidence regarding future sources of taxable income and tax planning strategies. However, there could be a material impact to our effective tax rate if there is a significant change in our estimates of future taxable income. If and when our estimates change, or there is a change in the value of deferred tax assets or liabilities warranting the need to reassess the realizability of deferred tax assets, we adjust a valuation allowance through the provision for income taxes in the period in which this determination is made. Refer to Note 13 of our Consolidated Financial Statements included in Item 8 of this Report for additional information regarding our deferred tax assets and liabilities.

Recently Issued Accounting Standards

Refer to Note 1 of the Consolidated Financial Statements included in Item 8 of this Report for information regarding recently issued accounting standards.

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Overview

We sell consumable products that utilize AC and chemical-based technologies to a broad range of customers, including coal-fired utilities, industrials, water treatment plants, and other diverse markets through a customer supply agreement described below. Our primary products are comprised of AC, which is produced from a variety of carbonaceous raw materials. Our AC products include both PAC and GAC. Our proprietary technologies and associated product offerings provide purification solutions to enable our customers to reduce certain contaminants and pollutants to meet the challenges of existing and potential future regulations. Additionally, we own the Five Forks Mine, a lignite mine that supplies the primary raw material for the manufacturing of our products.

Through December 31, 2021, we operated two segments: Refined Coal ("RC") and Advanced Purification Technologies ("APT"). Our RC segment was comprised of our equity ownership in Tinuum Group and Tinuum Services, both of which are unconsolidated entities from which we generated substantial earnings through December 31, 2021. We also earned royalties for technologies that we licensed to Tinuum Group, which were used at certain RC facilities to enhance combustion and reduce emissions of NOx and mercury from coal burned to generate electrical power. Effective December 31, 2021, the Section 45 tax credit period expired and, as a result, both Tinuum Group and Tinuum Services ceased their operations. During 2022, we received additional cash distributions from both Tinuum Group and Tinuum Services as they wound down their operations. We may receive additional cash distributions until both entities are dissolved.

Given the wind-down of Tinuum Group and Tinuum Services and the impact on our financial statements, we determined the historical RC segment no longer met the qualitative or quantitative criteria to be considered a reporting segment under U.S. GAAP. As a result, as well as the method in which the chief operating decision maker allocates resources, beginning January 1, 2022, we determined that we had one reportable segment, and therefore have removed segment disclosures for this Report.

Drivers of Demand and Key Factors Affecting Profitability

Drivers of demand and key factors affecting our profitability are sales of our consumables-based solutions for coal-fired power generation, industrials, municipal water customers and other diverse markets served by our major customer, Norit, to whom we sell product through the Supply Agreement discussed below. Our operating results are influenced by: (1) changes in our manufacturing production and sales volumes; (2) changes in price and product mix; (3) changes in coal-fired dispatch and electricity power generation sources and (4) changes in demand for contaminant removal within water treatment facilities. During 2022, we continued to see high demand for our AC products. As such, we continued to purchase inventory to supplement customer demands in excess of our production capacity and to achieve our target inventory levels. Although we expect to continue to supplement inventories throughout 2023, we anticipate that those purchases will be at reduced levels compared to 2022.

Supply Agreement

On September 30, 2020, we and Norit entered into the Supply Agreement, pursuant to which we agreed to sell and deliver to Norit, and Norit agreed to purchase and accept from us, our products. The term of the Supply Agreement is for 15 years with 10-year renewal terms that are automatic unless either party provides three years prior notice of intention not to renew before the end of any term.

For 2022 and 2021, the Supply Agreement provided material incremental volume and allowed us to capture operating cost efficiencies at the Red River Plant. The incremental volumes from the Supply Agreement have improved fixed cost absorption and resulted in increased gross margins. Further, the Supply Agreement has expanded our AC products to diverse end markets that are outside of those we historically served.

On February 25, 2022, we received $10.6 million in cash from Norit as a result of the Change in Control, of which $8.5 million represented full payment of an outstanding reimbursement amount related to reclamation of the Marshall Mine. As a result of the Change in Control, we recognized a loss of $0.5 million in settlement of the outstanding reimbursement. The Change in Control did not impact any other provisions of the Supply Agreement.

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Marshall Mine

Concurrently with the execution of the Supply Agreement, on September 30, 2020, we entered into the Mine Purchase Agreement from Cabot for 100% of the membership interests in Marshall Mine, LLC (the "Marshall Mine Acquisition") for a nominal purchase price. Marshall Mine, LLC owns a lignite mine located outside of Marshall, Texas (the "Marshall Mine"). We independently determined to immediately commenced activities to shutter the Marshall Mine and to incur the associated reclamation costs.

On September 2, 2022, we entered into a Purchase Agreement with a third party (the "MM Buyer") to sell all of our membership interests in Marshall Mine, LLC to the MM Buyer in exchange for a cash payment to be made by us to the MM Buyer of approximately $2.4 million and the assumption by the MM Buyer of certain liabilities of Marshall Mine, LLC (the "MM Sale"). The MM Buyer previously operated the Marshall Mine on behalf of Marshall Mine, LLC and is currently performing reclamation under the Reclamation Contract. The Purchase Price is subject to adjustments for certain events that may occur during the period from the Agreement Date and the Closing Date.

The obligations of the Parties to close the MM Sale is subject to certain events, including (1) obtaining the approval of the Commission for an operating permit in the name of the MM Buyer or an affiliate of the MM Buyer; and (2) the MM Buyer replacing the Seller’s surety bond with a reclamation performance bond, letter of credit or other form of security to which the MM Buyer or an affiliate of the MM Buyer is the principal that is satisfactory to the Commission. As of December 31, 2022, Marshall Mine, LLC had outstanding liabilities of approximately $4.9 million, which we expect to be fully discharged upon payment of the MM Sale. We currently expect to close the MM Sale during the first half of 2023. However, since the Closing Date is uncertain, primarily due to the uncertain date for the Parties to receive approval of the MM Buyer's operating permit and surety bond by the Commission, we are unable to determine the accounting period in which we will recognize the MM Sale.

Significant Transactions Occurring in 2023

Arq Acquisition

As previously discussed in Part I - Item 1. "Business" ("Item 1") of this Report, on February 1, 2023, we executed the Purchase Agreement and completed the Arq Acquisition through the issuance to Arq Ltd. of shares of our common stock and Series A Preferred Stock in exchange for all of the direct and indirect equity interests of Arq Ltd.'s subsidiaries. We accounted for the Arq Acquisition as an acquisition of a business as of the Acquisition Date. The total Purchase Consideration was $31.2 million based on the combined estimated fair values of the shares of Common Stock issued of $12.4 million and the shares of Series A Preferred Stock issued of $18.8 million.

Arq's principal office is located in London, United Kingdom, with additional offices located in Lexington and Corbin, Kentucky, near its main production facility. Arq is an environmental technology company that has developed a process for transforming coal waste into a purified, microfine carbon powder (Arq Powder) that can be used as an alternative to oil or in-ground mined coal to produce a range of carbon products. With the completion of the Arq Acquisition, we intend to first sell Arq Powder as a carbon filler for rubber composites and as a component for asphalt with an opportunity to evaluate expanding into other carbon products.

See further discussion of the Arq Acquisition and the material terms of the Series A Preferred Stock in Item 1.

PIPE Investment

As further described in Item 1 of this Report, on February 1, 2023, we closed the PIPE Investment for an aggregate purchase price of approximately $15.4 million and at a purchase price per common share of $4.00.

Loan Agreement

As further described in Item 1 of this Report, on February 1, 2023, ADES, as borrower, certain of its subsidiaries, as guarantors, and CF Global, as administrative agent and lender, entered into the Loan Agreement. The Term Loan has a term of 48 months and bears interest at a rate equal to either (a) Adjusted Term SOFR (subject to a 1.00% floor and a 2.00% cap) plus a margin of 9.00% paid in cash and 5.00% paid in kind or (b) Base Rate plus a margin of 8.00% paid in cash and 5.00% paid in kind, which interest on the Term Loan in each case shall be payable (or capitalized, in the case of in kind interest) quarterly in arrears. The Term Loan is secured by substantially all of the assets of ADES and its subsidiaries (including those acquired in the Transaction), subject to customary exceptions.

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In addition, and in connection with the Loan Agreement and as consideration for the Term Loan, we agreed to issue CF Global the Warrant to purchase 325,457 shares of Common Stock. The Warrant has an exercise price of $0.01 per share, subject to adjustment as set forth in the Warrant, is exercisable immediately and will expire on January 31, 2030. The terms of the Warrant do not allow for cash exercise, and the Warrant may only be exercised pursuant to the terms thereof.

See discussion of additional material terms of the Loan Agreement in "Liquidity and Capital Resources" of this Item 7 of this Report.

Termination of Transaction Agreement

As previously discussed in Item 1 of this Report, in connection with entry into the Purchase Agreement, the Transaction Agreement was terminated on February 1, 2023 pursuant to a termination agreement entered into by each of the parties to the Transaction Agreement. The Transaction Agreement would have provided, subject to its terms and conditions, for a business combination of Arq and ADES. By virtue of the termination of the Transaction Agreement, the Transaction Agreement became void and of no further force or effect, with no liability of the part of any party to the Transaction Agreement.

Components of Revenue, Expenses and Equity Method Investees

The following briefly describes the components of revenues and expenses as presented in the Consolidated Statements of Operations. Descriptions of the revenue recognition policies are included in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report.

Revenues and cost of revenues

Consumables

We sell AC products and other chemical-based technology products to a broad range of customers, including coal-fired utilities, industrials, water treatment plants and other diverse markets. Currently, our products mostly serve coal-fired utilities and other industrial boilers that allow the respective utilities to comply with the regulatory air emissions standards and water treatment plants to remove contaminants from the water. Additionally, we sell AC to Norit and its customers through the Supply Agreement.

Consumables cost of revenues

Consumables cost of revenues includes all labor, fringe benefits, subcontract labor, additive and coal costs, materials, equipment, supplies, travel costs and any other costs and expenses directly related to the Company’s production of revenues.

License royalties earned from Tinuum Group

Through December 2021, we generated revenues from royalties ("M-45 Royalties") earned under a licensing arrangement ("M-45 License") of our M-45TM and M-45-PCTM emissions control technologies ("M-45 Technology") between us and Tinuum Group, a related party. We recognized M-45 Royalties at a point in time based on the use of the M-45 Technology at certain RC facilities (the "M-45 Facilities") or through Tinuum Group’s use of licensed technology for rates in excess of amounts allowed for RC application. The amount of M-45 Royalties recognized was generally based on a percentage of pre-tax margins (as defined in the M-45 License) of the M-45 Facilities. With the expiration of the Section 45 tax credit program as of December 31, 2021, we no longer earn such royalties.

License royalties payable to Tinuum Group

In December 2022, the Company and Tinuum Group entered into an agreement (the "Tinuum Group Royalty Agreement") whereby we pay Tinuum Group a royalty (the "Tinuum Group Royalty") for certain of our sales of its M-ProveTM products after the expiration of the Section 45 Tax Credit Program (beginning January 1, 2022) to certain of the M-45 Facilities. The Tinuum Group Royalty is calculated based on "Net Profit" (as defined in the Tinuum Royalty Agreement) on our sales of M-ProveTM product to certain of the M-45 Facilities. The Tinuum Group Royalty Agreement is for an initial term of five years with automatic renewals of five years unless we and Tinuum Group agree to terminate it.

Other Operating Expenses

Payroll and benefits

Payroll and benefits costs include personnel related fringe benefits, sales and administrative staff labor costs and stock compensation expenses. Payroll and benefits costs exclude direct labor included in Cost of revenues.

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Legal and professional fees

Legal and professional costs include external legal, audit and consulting expenses.

General and administrative

General and administrative costs include director fees and expenses, bad debt expense, research and development expense and other general costs of conducting business. Research and development costs, net of reimbursements from cost-sharing arrangements, are charged to expense in the period incurred and are reported in the General and administrative line item in the Consolidated Statements of Operations.

Depreciation, amortization, depletion and accretion

Depreciation and amortization expense consists of depreciation expense related to property, plant and equipment and the amortization of long-lived intangible assets. Depletion and accretion expense consists of depletion expense related to the depletion of mine development costs and the accretion of mine reclamation liabilities.

Other Income (Expense), net

Earnings from equity method investments

Earnings from equity method investments represent our share of earnings (losses) related to our equity method investments. Through December 31, 2021, we had substantial earnings from Tinuum Group and Tinuum Services. With the expiration of the Section 45 tax credit program as of December 31, 2021, both Tinuum Group and Tinuum Services commenced winding down their operations related to the Section 45 tax credit program, although we have recognized earnings in 2022 related to cash distributions received.

Other income (expense)

The remaining components of other income (expense) include interest income, interest expense and other miscellaneous items.

Results of Operations

Presentation of Financial Results

For comparison purposes, the following tables set forth our results of operations for the years presented in the Consolidated Financial Statements included in Item 8 of this Report. The year-to-year comparison of financial results is not necessarily indicative of financial results that may be achieved in future years. Our Annual Report on Form 10-K for the year ended December 31, 2021 includes a discussion and analysis of our financial condition and results of operations for the year ended December 31, 2021 in Item 7 of Part II, "Management’s Discussion and Analysis of Financial Condition and Results of Operations."

Year ended December 31, 2022 Compared to Year ended December 31, 2021

Total Revenues and Cost of Revenues

A summary of the components of revenues and cost of revenue for the years ended December 31, 2022 and 2021 is as follows:

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Consumables revenues and consumables cost of revenues

For the years ended December 31, 2022 and 2021, consumables revenue increased year over year primarily driven by higher volumes sold, which comprised $11.8 million of the total change. Product volumes were higher among power generation customers primarily due to higher natural gas prices and higher demand for electricity compared to 2021, which contributed to increased utilization of coal-fired generation and increased demand for our products. Total consumables revenues also increased due to improved pricing for our products by approximately $6.3 million from 2021. Offsetting these increases to Consumable revenue was the impact of unfavorable product mix of approximately $1.4 million for the year ended December 31, 2022 compared to 2021.

Our Consumables gross margin, exclusive of depreciation and amortization, decreased for the year ended December 31, 2022 compared to 2021. For the year ended December 31, 2022, our consumables gross margin was negatively impacted by higher prices for key raw materials, transportation, including fuel, and other operational costs to produce and deliver our products, as well as an increase in the amount of third-party carbons purchased in order to meet customer demand for our products and supplement the higher operating utilization of the Red River Plant. Also negatively impacting Consumables gross margin for the year ended December 31, 2022 included $0.8 million of Tinuum Group Royalties. Offsetting these negative impacts were higher sales volumes, increases in the prices of our products implemented during the first half of 2022 and incremental positive impact from net electricity generated.

Consumables revenue continues to be affected by electricity demand, driven by seasonal weather and related power generation needs, as well as competitor prices related to alternative power generation sources such as natural gas and renewables.

For 2023, and based on current market estimates, we believe there will be a slight increase in Consumables revenue, driven by changes to customer and product mix, and overall improvements in pricing. However, we expect to see slight decreases in volumes compared to 2022 due to prices of alternative energy sources impacting the demand for our AC and chemical products related to power generation. There is risk to our outlook driven by inflationary pressures increasing our overall operating costs for our manufacturing operations as well as the impact of the 2023 Red River Plant turnaround.

License royalties, related party

As discussed above, Tinuum Group ceased operation as of December 31, 2021, and as a result, we did not recognize any revenues from license royalties from Tinuum Group for the year ended December 31, 2022.

Other Operating Expenses

A summary of the components of our operating expenses, exclusive of cost of revenues items (presented above), for the years ended December 31, 2022 and 2021 is as follows:

Payroll and benefits

Payroll and benefits expenses decreased year over year primarily due to a decrease in payroll-related expenses of $1.0 million as our headcount decreased year over year. Partially offsetting these decreases was an increase in expense of $0.2 million related to the Amended Retention Agreements, which were agreements between the Company and its executive officers and certain other key employees in order to maintain the Company's business operations while it pursued and executed on its strategic initiatives.

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Legal and professional fees

Legal and professional fees increased year over year as a result of an increase in costs incurred related to the Arq Acquisition. The increase was comprised mostly of legal and consulting fees of $0.9 million and $1.9 million, respectively. In addition, there was an increase in accounting related fees of approximately $0.4 million year over year.

General and administrative

General and administrative expenses increased year over year primarily due to increases in director compensation, travel and recruiting expenses, of approximately $0.7 million. Additionally, rent and occupancy related expenses increased year over year by $0.3 million.

Depreciation, amortization, depletion and accretion

Depreciation and amortization expense decreased year over year primarily due to higher production volumes during the year ended December 31, 2022, resulting in $0.9 million less absorption of depreciation in inventory. Further driving the decrease was a reduction in accretion expense of $0.5 million related to the reduction of the Marshall Mine ARO compared to prior year and a decrease in amortization expense of $0.4 million related to patents. Offsetting these decreases was an increase in depreciation expense of $0.2 million related to fixed asset additions during the year ended December 31, 2022.

Loss (gain) on change in estimate, asset retirement obligation

For the year ended December 31, 2022, we recorded a loss on change in estimate of $34 thousand primarily based on a change in the timing of estimated payments for future reclamation requirements of the Marshall Mine.

For the year ended December 31, 2021, we recorded a gain on change in estimate of $2.7 million related to a reduction in scope of our estimated future reclamation efforts of the Marshall Mine.

Other Income (Expense), net

A summary of the components of our other income (expense), net for the years ended December 31, 2022 and 2021 is as follows:

Earnings from equity method investments

The following table presents the equity method earnings by investee for the years ended December 31, 2022 and 2021:

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For the year ended December 31, 2022, we recognized $3.5 million in equity earnings from Tinuum Group compared to our proportionate share of Tinuum Group's net loss of $1.3 million for the year. For the year ended December 31, 2021, we recognized $61.8 million in equity earnings from Tinuum Group compared to our proportionate share of Tinuum Group's net income of $40.1 million. The difference between our pro-rata share of Tinuum Group's net (loss) income and our equity earnings from Tinuum Group as reported on the Consolidated Statements of Operations is the result of cumulative distributions received from Tinuum Group being in excess of the carrying value of the investment, and therefore we recognize such excess distributions as equity method earnings in the period the distributions occur.

For the year ended December 31, 2022, we recognized $0.1 million in equity earnings from Tinuum Services compared to our proportionate share of Tinuum Services' net loss of $0.1 million for this period. The difference between our pro-rata share of Tinuum Services' net loss and our earnings from the Tinuum Services equity method investment as reported on the Consolidated Statements of Operations is the result of cumulative distributions received from Tinuum Services being in excess of the carrying value of the investment, and therefore we recognize such excess distributions as equity method earnings in the period the distributions occur. For the year ended December 31, 2021, we recognized $7.7 million in equity earnings from Tinuum Services, which was our proportionate share of Tinuum Services' net income of $15.4 million for the year.

As of December 31, 2021, we concluded the carrying amount of our investment in Tinuum Services was not fully recoverable due to the remaining expected future cash distributions expected to be received as Tinuum Services shuttered its operations in 2022 as a result of the expiration of the Section 45 tax credit period as of December 31, 2021. As a result, we wrote-down our investment in the amount of $0.7 million, which is included in the "Earnings from equity method investments" line item in the Consolidated Statement of Operations for the year ended December 31, 2021.

Gain on extinguishment of debt

For the year ended December 31, 2021, we recorded a gain on extinguishment of debt in the amount of $3.3 million from a loan that we had entered into during 2020 under the Paycheck Protection Program. The loan was formally forgiven in July 2021.

Interest expense

Interest expense decreased year over year by $1.2 million primarily due to the pay-off of a senior term loan as of June 1, 2021.

Income tax expense

For the year ended December 31, 2022, our reported income tax expense was $0.2 million and was based on an effective rate of (2)%. The difference between our reported income tax expense and the expected federal benefit, as a result of pretax loss recognized for the year ended December 31, 2022, was primarily due to permanent differences related to acquisition-related costs, an increase in the valuation allowance on our deferred tax assets and state income taxes, net of federal benefit.

For the year ended December 31, 2021, our reported income tax expense of $15.7 million and was based on an effective rate of 21%. While the Federal Rate was also 21%, our effective tax rate was primarily increased by state income tax expense, net of federal benefit and primarily decreased from a reduction in the valuation allowance on our deferred tax assets.

Accounting for income taxes requires that companies assess whether a valuation allowance should be recorded against their deferred tax asset based on an assessment of the amount of the deferred tax asset that is "more likely than not" to be realized. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount that is more likely than not to be realized.

We assess a valuation allowance recorded against deferred tax assets at each reporting date. The determination of whether a valuation allowance for deferred tax assets is appropriate requires the evaluation of positive and negative evidence that can be objectively verified. Consideration must be given to all sources of taxable income available to realize the deferred tax asset, including, as applicable, the future reversal of existing temporary differences, future taxable income forecasts exclusive of the reversal of temporary differences and carryforwards, taxable income in carryback years and tax planning strategies. In estimating taxes, we assess the relative merits and risks of the appropriate tax treatment of transactions taking into account statutory, judicial, and regulatory guidance.

As of December 31, 2022, we concluded it is more likely than not we will not generate sufficient taxable income within the allowable carryforward periods to realize any of our net deferred tax assets, and fully reserved for such assets as of December 31, 2022. In reaching this conclusion, we primarily considered forecasts of future taxable losses. As of December 31, 2022 and 2021, we had a valuation allowance of $88.3 million and $87.5 million, respectively, on our deferred tax assets.

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The ability to recognize the remaining deferred tax assets that continue to be subject to a valuation allowance is evaluated on a quarterly basis to determine if there are any significant events that would affect the ability to utilize those deferred tax assets. Our estimate of future taxable income or losses is based on internal projections that consider historical performance, assumptions on future performance and external data. If events are identified that affect our ability to utilize our deferred tax assets, or if additional deferred tax assets are generated, we update our analysis to determine if an increase to a valuation allowance is required. Such an increase could have a material adverse effect on our financial condition and results of operations. Conversely, better than expected results and continued positive results and trends could result in a decrease to a valuation allowance, and any such decreases could have a material positive effect on our financial condition and results of operations.

See additional discussion in Note 13 of the Consolidated Financial Statements included in Item 8 of this Report.

Tax Credits and Obligations

Through December 31, 2021, we earned substantial tax credits under the Section 45 tax credit program, which program expired on December 31, 2021. As of December 31, 2022, we had approximately $86.1 million in Section 45 tax credit carryforwards.

In the hypothetical event of an ownership change, as defined by IRC Section 382, utilization of general business credits ("Tax Credits") generated prior to the change would be subject to an annual limitation imposed by IRC Section 383 for Tax Credits. The results of a recent analysis indicated that we had not experienced an ownership change as of December 31, 2022, as defined by IRC Section 382.

We performed an IRC Section 382 analysis related to the Arq Acquisition and PIPE Investment and determined we had not experienced an ownership change as of the Acquisition Date.

Such analysis for the period from the Acquisition Date through the date of this Report has not been completed. Therefore, it is possible that we experienced an ownership change between the Acquisition Date and the date of the filing of this Report, thus subjecting our Tax Credit carryforwards to limitation.

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Non-GAAP Financial Measures

To supplement our financial information presented in accordance with accounting principles generally accepted in the United States ("GAAP"), we provide non-GAAP measures of certain financial performance. These non-GAAP measures include EBITDA (EBITDA Loss) and Adjusted EBITDA (EBITDA Loss). We have included these non-GAAP measures because management believes that they help to facilitate period to period comparisons of our operating results and provide useful information to both management and users of the financial statements by excluding certain expenses, gains and losses which may not be indicative of core operating results and business outlook. Management uses these non-GAAP measures in evaluating the performance of our business.

These non-GAAP measures are not in accordance with, or an alternative to, measures prepared in accordance with GAAP and may be different from non-GAAP measures used by other companies. In addition, these non-GAAP measures are not based on any comprehensive set of accounting rules or principles. These measures should only be used to evaluate our results of operations in conjunction with the corresponding GAAP measures.

We define EBITDA (EBITDA Loss) as net income (loss) adjusted for the impact of the following items that are either non-cash or that we do not consider representative of our ongoing operating performance: depreciation, amortization, depletion, accretion, amortization of upfront customer consideration that was recorded as a component of the Marshall Mine Acquisition ("Upfront Customer Consideration"), interest expense, net and income tax expense. We define Adjusted EBITDA (EBITDA Loss) as EBITDA (EBITDA Loss), reduced by the non-cash impact of equity earnings from equity method investments, gain on change in estimate of asset retirement obligations and gain on extinguishment of debt, and increased by cash distributions from equity method investments, loss on early settlement of the Norit Receivable and the change in AROs as a result of a change in estimate. Because Adjusted EBITDA (EBITDA Loss) omits certain non-cash items, we believe that the measure is less susceptible to variances that affect our operating performance.

When used in conjunction with GAAP financial measures, we believe these non-GAAP measures are supplemental measures of operating performance which explain our operating performance for our period to period comparisons and against our competitors' performance. Generally, we believe these non-GAAP measures are less susceptible to variances that affect our operating performance results.

We expect the adjustments to EBITDA (EBITDA Loss) and Adjusted EBITDA (EBITDA Loss) in future periods will be generally similar. These non-GAAP measures have limitations as analytical tools and should not be considered in isolation or as a substitute for analyzing our results as reported under GAAP.

Reconciliation of Net (loss) income to (EBITDA Loss) EBITDA and Adjusted EBITDA

The following table reconciles net (loss) income, our most directly comparable as-reported financial measure calculated in accordance with GAAP, to (EBITDA Loss) EBITDA and Adjusted EBITDA.

(1) Included in Net loss for the year ended December 31, 2022, was $5.0 million of transactions costs incurred related to the Arq Acquisition.

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Liquidity and Capital Resources

Current Resources and Factors Affecting Our Liquidity

As of December 31, 2022, our principal future sources of liquidity included:

•cash on hand, excluding restricted cash of $10.0 million pledged as collateral under a surety bond agreement; and

•our operations

For the year ended December 31, 2022, our principal uses of liquidity included:

•our business operating expenses;

•capital and spare parts expenditures;

•payments on our lease obligations; and

•payments for reclamation associated with the Five Forks Mine and Marshall Mine.

On February 1, 2023, we closed the PIPE Investment for an aggregate purchase price of $15.4 million. Further, on February 1, 2023 we entered into the Loan Agreement for $10.0 million, of which we received $8.5 million net proceeds.

Due to the expiration of the Section 45 tax credit period as of December 31, 2021, and the resultant wind down of Tinuum Group's and Tinuum Services' operations in 2022, distributions from Tinuum Group and Tinuum Services are no longer a significant source of liquidity.

Tinuum Group and Tinuum Services Distributions

The following table summarizes the cash distributions from our equity method investments for the years ended December 31, 2022 and 2021:

Cash distributions from Tinuum Group and Tinuum Services for 2022 decreased by $68.1 million compared to 2021 primarily due to Tinuum Group and Tinuum Services ceasing material operations as of December 31, 2021.

Cash Flows

Cash and restricted cash decreased from $88.8 million as of December 31, 2021, to $76.4 million as of December 31, 2022, a decrease of $12.3 million. The following table summarizes our cash flows for the years ended December 31, 2022 and 2021, respectively:

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Cash flows from operating activities

Cash flows used in operating activities for the year ended December 31, 2022 was $6.1 million compared to cash flows provided by operating activities of $26.0 million for the year ended December 31, 2021. The net decrease was primarily due to the following: (1) a net change in net income (loss) of $69.3 million year over year as a result of net loss recognized for the year ended December 31, 2022; (2) a decrease in Distributions from equity method investees, return on investment of $20.6 million year over year; and (3) a decrease in the change in net working capital of $7.1 million year over year. Offsetting the net decrease in cash flows used in operating activities year over year were a decrease in Earnings from equity method investments of $65.2 million and Gain on extinguishment of debt of $3.3 million recorded in 2021.

Cash flows from investing activities

Cash flows used in investing activities for the year ended December 31, 2022 was $4.6 million compared to cash flows provided by investing activities of $44.4 million for the year ended December 31, 2021. The decrease was primarily due to a decrease in distributions from equity earnings in excess of cumulative earnings of $47.4 million and an increase in acquisitions of property and equipment year over year.

Cash flows from financing activities

Cash flows used in financing activities for the year ended December 31, 2022 decreased by $15.9 million compared to the year ended December 31, 2021 primarily due to the pay-off of a senior term loan of $16.0 million in 2021.

Material Cash Requirements

Our ability to continue to generate sufficient cash flow required to meet ongoing operational needs and obligations depends upon several factors. These include executing on our contracts and initiatives and increasing our share of the market for APT consumables, including expanding our overall AC business into additional adjacent markets and improving our customer and product mix.

We expect that our cash on hand as of December 31, 2022, as well as the cash proceeds related to the PIPE Investment and Term Loan, will provide sufficient liquidity to fund operations for the next 12 months.

Capital expenditures

For 2023, we expect to spend between $40.0 million and $45.0 million in capital expenditures compared to $9.5 million incurred in 2022. Of the capital expenditures forecasted in 2023, approximately 65% is expected to go towards growth projects as part of the Arq Acquisition and the remaining 35% is forecasted for improvements to the Red River Plant and Five Forks Mine, including our planned plant turnaround. Capital expenditures planned for 2023 are dependent on many factors, including the approval of certain environmental permits. Approval of such permits can impact the timing and amount of capital expenditures.

Retention Agreements

In August 2022, we paid $1.0 million pursuant to the payment terms of the Amended Retention Agreements. As of December 31, 2022, the remaining outstanding amount due under the Amended Retention Agreements was $1.4 million, which was paid on January 27, 2023.

Five Forks Mine and Marshall Mine Reclamation Obligations

As of December 31, 2022, we had outstanding surety bonds with regulatory commissions totaling $24.1 million related to both the Five Forks Mine and Marshall Mine. As of December 31, 2022, and as required by our surety bond provider, we held restricted cash of $10.0 million pledged as collateral related to performance requirements required under reclamation contracts for both the Five Forks Mine and Marshall Mine. We expect that the obligations secured by these surety bonds will be performed in the ordinary course of business and in accordance with the applicable contractual terms. To the extent that the obligations are performed, the related surety bonds should be released and collateral requirements reduced. However, in the event any surety bond is called, our indemnity obligations could require us to reimburse the surety bond provider.

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We intend to fund our mine reclamation costs associated with both the Five Forks Mine and Marshall Mine from cash on hand. On September 2, 2022, we executed the sale of all of our equity interests in Marshall Mine, LLC. We expect to close this transaction in the first half of 2023 at which time, we expect to fully discharge all liabilities associated with reclamation and also reduce both the surety bond and collateral requirements, as we will only be obligated for future reclamation costs for the Five Forks Mine.

Arq Reclamation Obligations

As of the Acquisition Date, we assumed surety bonds of Arq held with regulatory commissions totaling approximately of $3.0 million, of which approximately $2.9 million are related to the Corbin facility.

Contractual obligations as of December 31, 2022 are as follows:

(1) Includes total rental payments of $3.3 million under corporate headquarters and primary laboratory lease executed in November 2022 with lease commencement date of May 1, 2023.

The table above excludes our asset retirement obligation ("ARO") related to reclamation of the Five Forks Mine (the "Five Forks ARO"), as the timing and amount of payments to satisfy the Five Forks ARO are uncertain and are based on numerous factors including, but not limited to, the Five Forks Mine expected closure date. As of December 31, 2022, our Consolidated Balance Sheet reflects a liability of $3.9 million for the Five Forks ARO.

Loan Agreement

Under the terms of the Term Loan, executed on February 1, 2023, we are permitted to prepay the Term Loan at any time subject to the following prepayment premium: (i) prior to the twelve (12) month anniversary of the Closing Date, the Make-Whole Amount (as defined below), (ii) thereafter but prior to the thirty-six (36) month anniversary of the Closing Date, 2.00% of the outstanding principal amount of the Term Loan being repaid or prepaid or (iii) thereafter until the maturity date, 1.00% of the outstanding principal amount of the Term Loan being repaid or prepaid. The “Make-Whole Amount”, with respect to any repayment or prepayment, is (i) an amount equal to all required interest payable (except for currently accrued and unpaid interest) on the aggregate principal amount of the Term Loan subject to such prepayment or repayment from the date of such prepayment or repayment through but excluding the date that is the first anniversary of the Closing Date calculated using an interest rate equal to (x) Adjusted Term SOFR for an interest period of one month in effect on the third U.S. Government Securities Business Day prior to such prepayment or repayment plus (y) 14.00% per annum and assuming all interest was paid in cash, plus (ii) a prepayment premium of 2.00% on the aggregate principal amount of the Term Loan subject to such prepayment or repayment.

The Loan Agreement includes, among others, the following covenants: (1) beginning March 31, 2023 and as of the end of each fiscal quarter thereafter, we must maintain a minimum cash balance of $5.0 million; (2) (x) as of December 31, 2023, for the fiscal year then ended, we must have a minimum annual revenue, on a consolidated basis, of $70.0 million, (y) as of December 31, 2024, for the fiscal year then ended, we must have a minimum annual revenue, on a consolidated basis, of $85.0 million and (z) for any fiscal year thereafter, we must have a minimum annual revenue, on a consolidated basis, of $100.0 million; (3) (x) as of December 31, 2024, for the fiscal year then ended, we must have a minimum EBITDA of $3.0 million and (y) for any fiscal year thereafter, we must have a minimum EBITDA of $16.0 million; and (4) beginning after the fiscal quarter ending September 30, 2023, during an LTV Trigger Period, we must not exceed a loan to value (based on the consolidated total assets of ADES and its subsidiaries) ratio of 0.40:1.00.

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Critical Accounting Policies and Estimates

Our significant accounting policies are discussed in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report. In presenting our financial statements in conformity with GAAP, we are required to make estimates and assumptions that affect the amounts reported therein. Several of the estimates and assumptions we are required to make relate to matters that are inherently uncertain as they pertain to future events. Our estimates are based on historical experience and other assumptions believed to be reasonable under the circumstances, and we evaluate these estimates on an ongoing basis. Actual results may differ from these estimates under different assumptions or conditions.

We believe that the accounting estimates discussed below are critical to understanding our historical and future performance, as these estimates relate to the more significant areas involving management’s judgments and estimates.

Business Combinations, including asset acquisitions

We apply the acquisition method to acquisitions of both businesses and assets and allocate the purchase price to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the acquisition date. The purchase price allocation process requires us to make significant estimates and assumptions with respect to assets acquired and liabilities assumed. We believe the assumptions and estimates we make are reasonable, they are based in part on historical experience, market conditions and information obtained from management of the acquired company or group of assets and are inherently uncertain.

Examples of critical estimates in valuing certain of long-lived assets, including intangible assets, we have acquired or may acquire in the future include but are not limited to:

•future expected cash flows from revenues;

•historical and expected customer attrition rates and anticipated growth in revenues from acquired customers;

•the acquired company’s developed technology as well as assumptions about the period of time the acquired developed technology will continue to be used in the combined company's product portfolio;

•the expected use and useful lives of the acquired assets; and

•valuation methods and discount rates used in estimating the values of the assets acquired and liabilities assumed.

In regard to the Marshall Mine Acquisition, which we accounted for as an asset acquisition, we recorded the fair value of assumed assets, which included property, plant and equipment and spare parts and assumed liabilities. In addition, we recorded other assets, including Upfront Customer Consideration and the Cabot Receivable, and a liability for the Marshall Mine ARO.

Carrying value of long-lived assets and intangibles

We review and evaluate our long-lived assets and intangibles for impairment at least annually, or more frequently when events or changes in circumstances indicate that the related carrying amounts may not be recoverable. An impairment loss is measured and recorded for long-lived assets and intangibles based on the excess of their carrying amounts over their estimated fair values. Fair value is typically determined through the use of an income approach utilizing estimates of discounted pretax future cash flows or a market approach utilizing recent transaction activity for comparable assets.

Asset Retirement Obligations

Accounting for AROs requires us to make estimates of future costs unique to a specific mining operation that we will incur to complete the reclamation and remediation work required to comply with existing laws and regulations. Any such changes in future costs, the timing of reclamation activities, scope or the exclusion of certain costs not considered reclamation and remediation costs could materially impact the amounts charged to earnings for reclamation and remediation. Additionally, future changes to environmental laws and regulations could increase the scope of reclamation and remediation work required.

Five Forks Mine ARO - Reclamation costs related to the Five Forks Mine ARO are allocated to expense over the life of the related mine assets and are periodically adjusted to reflect changes in the estimated present value resulting from the passage of time and revisions to the estimates of either the timing or amount of the reclamation costs. Remediation costs for the Five Forks Mine are accrued based on management’s best estimate of the costs expected to be incurred. Such cost estimates may include ongoing care, maintenance and monitoring costs. Reclamation obligations are based on the timing of estimated spending for an existing environmental disturbance. We review, on at least an annual basis, the future expected costs and the timing of such costs for the Five Forks Mine ARO.

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Marshall Mine ARO - Reclamation costs related to the Marshall Mine are based on a capped fee structure for a significant portion of the ARO liability based on the initial estimate of the total costs of reclamation, which provides for certain contingencies that could increase or decrease the reclamation fee based on the reclamation agreement executed between us and the Marshall Mine operator. The timing of payments may vary, and in valuing the Marshall Mine ARO, we account for these timing differences, as well as changes in actual reclamation costs, on a quarterly basis.

Income Taxes

We account for income taxes under the asset and liability method, which requires judgment in determining income tax expense and the related balance sheet amounts. This includes estimating and analyzing historical and projected future operating results, the reversal of taxable temporary differences, tax planning strategies, and the ultimate outcome of uncertain income tax positions. Actual income taxes paid may vary from estimates depending on changes in income tax laws, actual results of operations, state apportionment and, if applicable, final audits of tax returns by taxing authorities. Tax assessments may arise several years after tax returns have been filed. Changes in the estimates and assumptions used for calculating income tax expense and potential differences in actual results from estimates could have a material impact on our results of operations and financial condition.

We recognize deferred tax assets to the extent that we believe these assets are more likely than not to be realized. In making such a determination, we consider all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies and results of recent operations.

We establish a valuation allowance against our deferred tax assets when, based upon the weight of all available evidence, we believe it is more likely than not that some portion or all of the deferred tax assets will not be realized. In making this determination, we consider the relative impact of all of the available positive and negative evidence regarding future sources of taxable income and tax planning strategies. However, there could be a material impact to our effective tax rate if there is a significant change in our estimates of future taxable income. If and when our estimates change, or there is a change in the value of deferred tax assets or liabilities warranting the need to reassess the realizability of deferred tax assets, we adjust a valuation allowance through the provision for income taxes in the period in which this determination is made. Refer to Note 13 of our Consolidated Financial Statements included in Item 8 of this Report for additional information regarding our deferred tax assets and liabilities and related deferred income tax expense (benefit).

Recently Issued Accounting Standards

Refer to Note 1 of the Consolidated Financial Statements included in Item 8 of this Report for information regarding recently issued accounting standards.

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Overview

Through December 31, 2021, we operated two segments: RC and APT. Our RC segment is comprised of our equity ownership in Tinuum Group and Tinuum Services, both of which are unconsolidated entities from which we generated substantial earnings. Tinuum Group provides reduction of mercury and NOx emissions at select coal-fired power generators through the production and sale of RC that qualifies for Section 45 tax credits under IRC Section 45. We benefited from Tinuum Group's production and sale of RC, which generated Section 45 tax credits, as well as its revenue from selling or leasing RC facilities to tax equity investors. We also earned royalties for technologies that we licensed to Tinuum Group, which were used at certain RC facilities to enhance combustion and reduce emissions of NOx and mercury from coal burned to generate electrical power. Tinuum Services operated and maintained the RC facilities under operating and maintenance agreements with Tinuum Group and owners or lessees of the RC facilities. Effective December 31, 2021, the Section 45 tax credit period expired and as a result both Tinuum Group and Tinuum Services have substantially ceased their operations. As such, our earnings and distributions from our RC segment substantially ceased as of December 31, 2021. We expect to receive limited, additional cash distributions from Tinuum Group and Tinuum Services during the first half of 2022.

Our APT segment is primarily comprised of operations of our wholly-owned subsidiary, Carbon Solutions, which we acquired on December 7, 2018. We sell consumable products that utilize AC and chemical based technologies to a broad range of customers, including coal-fired utilities, industrials, water treatment plants and other diverse markets. Our primary products are comprised of AC, which is produced from lignite coal. Our AC products include PAC and GAC. Our proprietary technologies and associated product offerings provide purification solutions to enable our customers to reduce certain contaminants and pollutants to meet the challenges of existing and potential regulations. Additionally, we own an associated lignite mine which supplies the primary raw material for manufacturing our products.

See further discussion of our business included in Item 1 - "Business" ("Item 1") of this Report. Discussion regarding segment information is included in the discussion of our consolidated results under this Item 7. Additionally, discussion related to our reportable segments is included in Item 1 and Note 19 of the Consolidated Financial Statements, which is included in Item 8 of this Report.

We believe there are opportunities and are continuing to pursue diverse markets for our purification products outside of coal-fired power generation, including industrial applications and water. The Supply Agreement with Cabot, as discussed below, continues to expand sales of our AC products to those diverse end-markets and drive the Company’s post-Refined Coal future.

Review of Strategic Alternatives

In May 2021, we announced that we had retained Ducera Partners, LLC as our financial advisor to assist in a strategic review process to assess a range of strategic alternatives to enhance value for our stockholders. We cannot provide any assurance that the exploration of strategic alternatives will result in the identification or consummation of any transaction. Similarly, any strategic decision will involve risks and uncertainties, and we cannot provide any assurance that any strategic alternative, if identified, evaluated and consummated, will provide the anticipated benefits or otherwise enhance stockholder value. The process is ongoing and our board of directors has not set a timetable for completion of the evaluation.

Drivers of Demand and Key Factors Affecting Profitability

Drivers of demand and key factors affecting our profitability differ by segment. Historically, we derived substantial earnings and cash distributions from the RC segment through our equity ownership in Tinuum Group and Tinuum Services as well as the royalties earned from a licensing arrangement with Tinuum Group for use of our M-45 Technology. With the expiration of the Section 45 tax credit period, we will no longer generate earnings from either Tinuum Group or Tinuum Services. Additionally, we do not expect our overall selling, general and administrative portions of our operating expenses to materially decrease in 2022 as a result of the wind down of our RC segment.

Demand in the APT segment is driven primarily by consumables-based solutions for coal-fired power generation, municipal water treatment and other industrial customers; and since the fourth quarter of 2020, demand from Cabot's customers through the Supply Agreement discussed below. Operating results in the APT segment have been influenced by: (1) changes in our sales volumes; (2) changes in price and product mix; (3) changes related to non-integrated supply chain inputs and (4) changes in coal-fired dispatch and electricity power generation sources. For the year ended December 31, 2021, we observed significant

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increases in demand for our AC product. As such, we continue to purchase inventory to meet our customer demands to supplement products manufactured at our Red River Plant.

Customer Supply Agreement

On September 30, 2020, we and Cabot entered into the Supply Agreement, pursuant to which we agreed to sell and deliver to Cabot, and Cabot agreed to purchase and accept from us, Furnace Products. The term of the Supply Agreement is for 15 years with 10-year renewal terms that are automatic unless either party provides three years prior notice of intention not to renew before the end of any term.

The Supply Agreement has provided material incremental volume and allowed us to capture operating cost efficiencies at our Red River manufacturing plant. The incremental volumes from the Supply Agreement have improved fixed cost absorption and resulted in increased gross margins. Further, the Supply Agreement has expanded our AC products to diverse end markets that are outside of markets we historically served.

Acquisition of Marshall Mine

Concurrently with the execution of the Supply Agreement, on September 30, 2020, we entered into the Mine Purchase Agreement from Cabot for 100% of the membership interests in Marshall Mine, LLC (the "Marshall Mine Acquisition") for a nominal purchase price. Marshall Mine, LLC owns a lignite mine located outside of Marshall, Texas (the "Marshall Mine"). We independently determined to immediately commence activities to shutter the Marshall Mine and to incur the associated reclamation costs.

In conjunction with the execution of the Supply Agreement and the Mine Purchase Agreement, on September 30, 2020, we entered into the Reclamation Contract with a third party that provides a capped cost, subject to certain contingencies, in the amount of approximately $19.7 million plus an obligation to pay certain direct costs of approximately $3.6 million (collectively, the "Reclamation Costs") over the estimated reclamation period of 10 years. Under the terms of the Supply Agreement, Cabot is obligated to reimburse us for approximately $10.2 million of Reclamation Costs (the "Reclamation Reimbursement"), which are payable semi-annually over 13 years and inclusive of interest.

On February 25, 2022, we received $10.6 million in cash from Cabot (the "Cabot Payment") as a result of a change in control provision in the Supply Agreement (the "Change in Control"), which occurred as a result of the sale of Cabot by its parent, Cabot Corporation. Under the Change in Control, we received from Cabot full payment of all amounts outstanding under the Reclamation Reimbursement, payment of all unbilled amounts related to certain capital expenditures incurred by us through February 28, 2022 for specific use in manufacturing Furnace Products and payment of additional Reclamation Costs (the "Cabot Reclamation Costs"). Under the Reclamation Contract, we are obligated to remit payment for the Cabot Reclamation Costs to the third party operator of Marshall Mine within a specified timeframe. We will account for the Cabot Payment in its March 31, 2022 quarter and we do not anticipate any impacts to the Supply Agreement except as described above.

As the owner of the Marshall Mine, we were required to post a surety bond to ensure performance of our reclamation activities. As of December 31, 2021, the amount outstanding under this surety bond was $16.6 million. For the obligations due under the Reclamation Contract, we were required to post collateral of $10.0 million.

As of June 30, 2021 and December 31, 2021, we revised our estimate of future obligations owed for reclamation of the Marshall Mine primarily based on scope reductions related to future reclamation requirements. As a result, we reduced the Marshall Mine ARO by $1.9 million and $0.8 million as of June 30, 2021 and December 31, 2021, respectively, and recorded a corresponding gain on change in estimate in the aggregate of $2.7 million in the Consolidated Statements of Operations for the year ended December 31, 2021.

Settlement with Former Customer

On December 29, 2020, we and a former customer (the "Parties") reached a settlement (the "Settlement") on various litigation matters (the "Litigation Matters") that resulted in the former customer (the "Former Customer") agreeing to pay to us cash of $2.5 million (the "Settlement Amount"), which was received on January 27, 2021. This payment was in exchange for full dissolution of all claims and counterclaims that the two Parties have asserted or could have asserted against each other in the Litigation Matters, or which have arisen or may arise against each other but are presently unknown, arising out of or related to the Litigation Matters and related to any other of the Parties’ business dealings, conduct and/or transactions through the date of the Settlement, including all claims for damages, fees, costs, sanctions, or any other amounts due or to become due in connection with the foregoing. We applied the Settlement Amount cash proceeds to both an outstanding trade account

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receivable and a note receivable due from the Former Customer and recognized the excess cash received as a gain from the Settlement of $1.1 million, which is included as a reduction of operating expenses for the year ended December 31, 2020, See further discussion under "Results of Operations" under this Item 7.

Impact of COVID-19

In March 2020, the World Heath Organization declared COVID-19 a global pandemic. We follow the COVID-19 guidelines from the Centers for Disease Control concerning the health and safety of our personnel, including remote working for those that have the ability to do so, sequestered employees at our plant and other heath safety measures. Additionally, we have taken proactive and precautionary steps to ensure the safety of our employees, customers and suppliers, including frequent cleaning and disinfection of workspaces, property, plant and equipment, instituting social distancing measures and mandating remote working environments, where possible, for all employees.

In response to the COVID-19 outbreak, in March 2020, the federal government passed the Coronavirus Aid, Relief, and Economic Security Act (the "CARES Act"). The CARES Act provided, among other things, the deferral of payroll tax payments for all payroll taxes incurred through December 31, 2020 and created the Paycheck Protection Program ("PPP"), which was sponsored and administered by the Small Business Administration ("SBA"). In June 2020, the Paycheck Protection Program Flexibility Act of 2020 (the "PPPFA") was signed into law and established the payment dates in the event that amounts borrowed under the PPP are not forgiven. See further discussion below of the loan made to us under the PPP under the section "PPP Loan" under this Item.

We elected to defer payments of payroll taxes of $0.4 million for the periods allowed under the CARES Act, which allowed for a deferral of 50% of the total amount to December 31, 2021 and 50% of the total amount to December 31, 2022. As of December 31, 2021, we had repaid $0.2 million and will repay the outstanding balance by December 31, 2022.

For 2020, we incurred costs of $0.4 million related to sequestration of certain of our employees at our Red River plant. These costs included hazard pay, lodging and meal expenses for 30 days. For 2021, we did not incur similar costs.

Our customers may also be impacted by COVID-19 pandemic as we believe the utilization of energy has changed. We cannot predict the long-term impact on our customers and the subsequent impact on our business.

Components of Revenue, Expenses and Equity Method Investees

The following briefly describes the components of revenues and expenses as presented in the Consolidated Statements of Operations. Descriptions of the revenue recognition policies are included in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report.

Revenues and cost of revenues

Consumables

We sell AC and products and other chemical-based technology products to a broad range of customers, including coal-fired utilities, industrials, water treatment plants and other diverse markets. Currently, our products mostly serve coal-fired utilities and other industrial boilers that allow the respective utilities to comply with the regulatory air emissions standards and water treatment plants to remove contaminants from the water. Additionally, we sell AC to Cabot and its customers through the Supply Agreement.

License royalties, related party

We recognize license royalties under the M-45 License with Tinuum Group. License royalties from our M-45 Technology are based on a percentage of the per-ton, pre-tax margin, inclusive of depreciation expense and other allocable expenses, as defined in the M-45 License. Because Section 45 tax credits from the production and sale of RC are not available to be generated after 2021 and both Tinuum Group and Tinuum Services significantly wound down their operations by the end of 2021, we do not expect to earn license royalties after 2021.

Other Operating Expenses

Payroll and benefits

Payroll and benefits costs include personnel related fringe benefits, sales and administrative staff labor costs and stock compensation expenses. Payroll and benefits costs exclude direct labor included in Cost of revenues.

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Legal and professional fees

Legal and professional costs include external legal, audit and consulting expenses.

General and administrative

General and administrative costs include director fees and expenses, bad debt expense, research and development expense and other general costs of conducting business. Research and development costs, net of reimbursements from cost-sharing arrangements, are charged to expense in the period incurred and are reported in the General and administrative line item in the Consolidated Statements of Operations.

Depreciation, amortization, depletion and accretion

Depreciation and amortization expense consists of depreciation expense related to property, plant and equipment and the amortization of long-lived intangible assets. Depletion and accretion expense consists of depletion expense related to the depletion of mine development costs and the accretion of mine reclamation liabilities.

Other Income (Expense), net

Earnings from equity method investments

Earnings from equity method investments represent our share of earnings (losses) related to our equity method investments.

We own a 42.5% equity interest and a 50% voting interest in Tinuum Group. Our equity method earnings in Tinuum Group are positively impacted when Tinuum Group obtains an investor in a RC facility and receives cash payments under either a lease arrangement or sales arrangement of the RC facility. If Tinuum Group operates a retained RC facility, the Company's equity method earnings are negatively impacted as operating retained RC facilities generate operating losses. However, we benefit on an after-tax basis if we are able to utilize tax credits associated with the production and sale of RC from operation of retained RC facilities by Tinuum Group. These benefits, if utilized, increase our consolidated net income as a result of a reduction in income tax expense.

We own both a 50% equity and voting interest in Tinuum Services, which operates and maintains RC facilities under operating and maintenance agreements. The lessee/owner of an RC facility pays Tinuum Services, subject to certain limitations, the costs of operating and maintaining the RC facilities plus certain fees. Tinuum Services also arranges for the purchase and delivery of certain chemical additives under chemical agency agreements necessary for the production of RC.

Other income (expense)

The remaining components of other income (expense) include interest income, interest expense and other miscellaneous items.

Results of Operations

Presentation of Financial Results

For the year ended December 31, 2020, we have restated our "Revenues - Consumables" and "Cost of revenues, excluding depreciation and amortization" line items in our Consolidated Statement of Operations for the impact of previously reporting shipping and handling costs billed to our customers as a reduction to cost of revenue rather than as a component of consumables revenue. This restatement was a result of a reassessment of our accounting and presentation of shipping and handling costs billed to our customers under accounting principles generally accepted in the United States ("GAAP") in our Consolidated Statement of Operations for the year ended December 31, 2021. Historically, we have accounted for and presented shipping and handling costs billed to customers as a reduction of consumables cost of revenue rather than as a component of consumables revenue as required under Accounting Standards Codification 606 - Revenue from Contracts with Customers. Accordingly, we have restated both consumables revenues and consumable cost of revenues for the year ended December 31, 2020 by increasing the previously reported amounts by $5.8 million, respectively.

For the year ended December 31, 2020, there was no impact of the restatement to previously reported amounts for gross margin, operating loss, loss before income taxes, net loss or loss per share. Further there was no impact of this error to the previously reported Consolidated Balance Sheet as of December 31, 2020 or the Consolidated Statement of Stockholders' Equity or Consolidated Statement of Cash Flows for the year ended December 31, 2020. See further discussion of this restatement in Note 2 to the Consolidated Financial Statements under Item 8 of this Report.

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For comparison purposes, the following tables set forth our results of operations for the years presented in the Consolidated Financial Statements included in Item 8 of this Report. The year-to-year comparison of financial results is not necessarily indicative of financial results that may be achieved in future years. Our Annual Report on Form 10-K for the year ended December 31, 2020 includes a discussion and analysis of our financial condition and results of operations for the year ended December 31, 2019 in Item 7 of Part II, “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Year ended December 31, 2021 Compared to Year ended December 31, 2020

Total Revenues and Cost of Revenues

A summary of the components of revenues and cost of revenue for the years ended December 31, 2021 and 2020 is as follows:

Consumables revenues and consumables cost of revenues

For the years ended December 31, 2021 and 2020, consumables revenue increased year over year primarily due to higher product volumes, which comprised approximately $25.0 million of the total change in consumables revenues. Product volumes were higher in power generation primarily due to higher natural gas prices compared to the prior year, which contributed to increased utilization of coal-fired generation and increased demand for our products. In addition, product sales increased under the Supply Agreement from the prior year as we began product shipments under this agreement beginning in the fourth quarter of 2020. Total revenues also increased due to a favorable price impact of our products by approximately $1.0 million as well as favorable product mix impact on consumables revenue of approximately $4.1 million. Consumables revenue for 2021 also increased $0.9 million related to an increase in shipping and handling costs billed to our customers, driven by increases in volumes and costs to ship our products.

Our gross margin, exclusive of depreciation and amortization, increased for the year ended December 31, 2021 compared to 2020 primarily due to the higher product volumes, which resulted in lower fixed costs per pound of product sold. Additionally, gross margin was positively impacted by product price increases. Offsetting these improvements for the year ended December 31, 2021, gross margin was negatively impacted by having to supplement the Red River production of our AC product, due to higher customer demand related to requirements-based contracts, with AC product purchases from third party suppliers at higher costs per pound. We expect to continue to purchase inventory from third party suppliers in 2022 due to ongoing increased demand for our products and Red River Plant capacity impacted by customer and product mix.

Consumables revenue is affected by electricity demand, driven by seasonal weather and related power generation needs, as well as competitor prices related to alternative power generation sources such as natural gas. According to data provided by the U.S. Energy Information Administration, for the year ended December 31, 2021, power generation from coal-fired power dispatch was up approximately 18.0% compared to the corresponding period in 2020. Additionally, there was an increase in total power generation from all sources of approximately 3.1% in 2021 compared to the corresponding period in 2020.

For 2022, and based on current market estimates and the expected benefits from the Supply Agreement, we believe that both consumables revenue and volumes will increase compared to 2021. We expect that consumables revenues and gross margin will be positively impacted by price increases announced in 2021 and our efforts to improve product mix to higher margin products through changes in our customer base. We anticipate that the product price increases will also help offset the increase

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in operating costs from purchasing inventory from third party suppliers, as well as expected increases in pricing related to certain additives necessary for our manufacturing operations.

License royalties, related party

License royalties increased in 2021 compared to 2020 primarily due to an increase in the royalty rate per ton. This increase was primarily a result of an increase year over year in rent revenues generated from RC facilities even though the tonnage produced remained relatively flat. The tons of RC produced from RC produced using the M-45 Technology under the M-45 License were 49.3 million and 49.4 million for the year ends December 31, 2021 and 2020, respectively.

As a result of the Section 45 tax credit period ending as of December 31, 2021, both Tinuum Group and Tinuum Services ceased operations and, as such, we do not expect to earn M-45 License royalties after December 31, 2021.

Other cost of revenues

For the year ended December 31, 2020, we recognized a credit of $0.6 million to Other cost of revenues related to the Settlement with the Former Customer. See further discussion below of the reversal of an allowance on a note receivable due from the Former Customer in this section under the caption "General and administrative."

Additional information related to revenue concentrations and contributions by class and reportable segment is included in the "Business Segments" section of this Item and in Note 13 and Note 19 to the Consolidated Financial Statements included in Item 8 of this Report.

Other Operating Expenses

A summary of the components of our operating expenses, exclusive of cost of revenues items (presented above), for the years ended December 31, 2021 and 2020 is as follows:

* Calculation not meaningful

Payroll and benefits

Payroll and benefits expenses increased year over year primarily due to expenses of $1.1 million related to the agreements with our executive officers and certain other key employees executed in June 2021 ("Retention Agreements") as well as $1.3 million related to an increase in incentive expense for the year ended December 31, 2021 compared to 2020. These increases were offset by a decrease in expenses taken during the year ended December 31, 2020 of $1.4 million associated with the resignation of a former executive officer. Additionally, payroll expense decreased by approximately $0.5 million due to a decrease in headcount.

Legal and professional fees

Legal and professional fees increased year over year primarily due to an increase in legal and consulting fees of $0.9 million and $1.2 million, respectively, related to our continuing evaluation of strategic alternatives. Offsetting these increases was $0.9 million related to a reduction in outsourced shared service costs, which included legal and general consulting contractors, and $0.5 million in outsourced IT costs specific to the completion of the integration of Carbon Solutions in 2020.

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General and administrative

General and administrative expenses decreased year over year primarily due to decreases in product development expenses of approximately $0.6 million related to the Supply Agreement, costs incurred due to the sequestration of certain of our employees at the Red River Plant in 2020 of approximately $0.4 million, rent and occupancy related expenses of $0.3 million and other general and administrative expenses, including recruiting, travel and licenses and fees of approximately $0.7 million.

Offsetting the net decrease in general and administrative expenses year over year was the offset to general and administrative expenses in 2020 from the reversal of an allowance on a note receivable from the Former Customer of $0.4 million. See further discussion below in this section under the caption "Gain on settlement." Further increases year over year included an increase in insurance premiums of approximately $0.4 million.

Depreciation, amortization, depletion and accretion

Depreciation and amortization expense decreased year over year primarily due to lower absorption from the drawdown of inventory, partially offset by increase in sales volumes for 2021, resulting in a decrease of depreciation expense of $0.2 million. Further, depreciation and amortization expense decreased by approximately $1.1 million related to a lower depreciable base for 2021 compared to 2020 as a result of an impairment charge recorded in the second quarter of 2020 which reduced the carrying value of our property, plant and equipment. Offsetting these decreases was an increase in accretion expense of $0.6 million related to the Marshall Mine ARO and an increase in depletion expense of $0.2 million due to increased production volume at the Five Forks Mine.

Gain on change in estimate, asset retirement obligation

As previously discussed under this Item, for the year ended December 31, 2021, we recorded a gain on change in estimate of $2.7 million related to a reduction in scope of our estimated future reclamation efforts of the Marshall Mine.

Impairment of long-lived assets

As of June 30, 2020, we recorded an impairment charge of $26.1 million, which is included in the Statement of Operations for the year ended December 31, 2020 and was solely attributable to our APT segment. This impairment charge was necessitated by an analysis of the carrying values of our APT segment's long-lived assets and certain other long-lived assets (the "Asset Group"), which are comprised of our manufacturing plant and related assets and our lignite mine assets, to their respective fair values.

Gain on settlement

In connection with the Settlement discussed above, the Former Customer paid us the cash Settlement Amount of $2.5 million on January 27, 2021 in exchange for a full release of claims in the Litigation Matters. As a result of the Settlement, we recognized a gain of $1.1 million for the year ended December 31, 2020.

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Other Income (Expense), net

A summary of the components of our other income (expense), net for the years ended December 31, 2021 and 2020 is as follows:

* Calculation not meaningful

Earnings from equity method investments

The following table presents the equity method earnings by investee for the years ended December 31, 2021 and 2020:

* Calculation not meaningful

For the year ended December 31, 2021, we recognized $61.8 million in equity earnings from Tinuum Group compared to our proportionate share of Tinuum Group's net income of $40.1 million for the year. The difference between our pro-rata share of Tinuum Group's net income and our earnings from Tinuum Group equity method investment as reported on the Consolidated Statements of Operations is the result of cumulative distributions received from Tinuum Group being in excess of the carrying value of the investment, and therefore we recognize such excess distributions as equity method earnings in the period the distributions occur.

For the year ended December 31, 2020, we recognized $24.4 million in equity earnings from Tinuum Group, which was equal to our proportionate share of Tinuum Group's net income for the year.

As of December 31, 2021, we concluded the carrying amount of our investment in Tinuum Services was not fully recoverable due to the remaining expected future cash distributions to be received as Tinuum Services shutters its operations in 2022 as a result of the expiration of the Section 45 tax credit period as of December 31, 2021. As a result, we wrote-down our investment in the amount of $0.7 million, which is included in the "Earnings from equity method investments" line item in the Consolidated Statement of Operations for the year ended December 31, 2021.

See further discussion of year over year changes in Earnings from Equity Investments in "Business Segments" under this Item. Additional information related to equity method investments is included in Note 8 to the Consolidated Financial Statements included in Item 8 of this Report.

Tinuum Group's audited consolidated financial statements as of December 31, 2021 and 2020 and for the years then ended are included in Item 15 - "Exhibits and Financial Statement Schedules" ("Item 15") of this Report.

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Gain on extinguishment of debt

On July 27, 2021, we received formal notification in the form of a letter dated July 19, 2021 from Bank of Oklahoma ("BOK") that the SBA approved our PPP Loan forgiveness application for the PPP Loan in the amount of $3.3 million (including accrued interest). For the year ended December 31, 2021, we recorded a gain on extinguishment of the PPP Loan in the amount of $3.3 million in the Consolidated Statement of Operations, which is included as a component of "Other income (expense)."

Tax Credits and Obligations

Historically, we have earned Section 45 tax credits that may be available for future benefit related to the production of RC from the operation of RC facilities in which we have held both direct ownership and indirect ownership through Tinuum's direct ownership. We refer to these RC facilities as "retained facilities." The Section 45 tax credit period ended December 31, 2021 and we will not earn Section 45 tax credits beyond this date. As of December 31, 2021, we had approximately $86.1 million in Section 45 tax carryforwards.

In the hypothetical event of an ownership change, as defined by IRC Section 382, utilization of general business credits ("GBC's") generated prior to the change would be subject to an annual limitation imposed by IRC Section 383 for GBC's. The results of a recent analysis indicated that we had not experienced an ownership change as of December 31, 2021, as defined by IRC Section 382. Such analysis for the period from January 1, 2022 through the date of this Report has not been completed. Therefore, it is possible that we experienced an ownership change between January 1, 2022 and the date of the filing of this Report, thus subjecting our GBC carryforwards to limitation.

Interest expense

Interest expense decreased year over year by $2.4 million primarily due to principal payments made in 2021 on a senior term loan (the "Senior Term Loan") that resulted in lower coupon interest expense of $1.5 million. Interest expense for debt discount and debt issuance costs related to the Senior Term Loan also decreased by $0.5 million pursuant to the decrease in the Senior Term Loan principal. On June 1, 2021 and prior to the Senior Term Loan's maturity date, we paid the remaining principal balance of the Senior Term Loan and all remaining accrued interest through this date.

The remaining decrease in interest expense year over year related to lower interest expense ("Section 453A interest") related to IRS section 453A ("Section 453A"), which decreased by $0.3 million primarily due to a decrease in Tinuum Group's the tax liability year over year associated with RC facilities in which Tinuum Group recognized as installment sales for tax purposes.

The following table shows the balance of the tax liability that has been deferred and the applicable interest rate used to calculate the 453A interest liability:

(1) Represents the approximate tax effected liability utilizing the federal tax rate in effect for the applicable year ended related to the deferred gain on installment sales, which was approximately zero as of December 31, 2021.

Income tax expense

For the year ended December 31, 2021, our reported income tax expense was $15.7 million and was based on an effective rate of 21%. While the U.S. statutory federal income tax rate (the "Federal Rate") was also 21%, our effective tax rate was primarily increased for state income tax expense, net of federal benefit, and decreased from a reduction in the valuation allowance on our deferred tax assets.

For the year ended December 31, 2020, our reported income tax expense of $6.5 million and was based on an inverse effective rate of 47%, which differed from the Federal Rate of 21% due to primarily an increase in the valuation allowance on our deferred tax assets. This increase in the valuation allowance resulted in income tax expense rather than expected income tax benefit based on the pretax loss.

Accounting for income taxes requires that companies assess whether a valuation allowance should be recorded against their deferred tax asset based on an assessment of the amount of the deferred tax asset that is “more likely than not” to be realized.

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Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount that is more likely than not to be realized.

We assess a valuation allowance recorded against deferred tax assets at each reporting date. The determination of whether a valuation allowance for deferred tax assets is appropriate requires the evaluation of positive and negative evidence that can be objectively verified. Consideration must be given to all sources of taxable income available to realize the deferred tax asset, including, as applicable, the future reversal of existing temporary differences, future taxable income forecasts exclusive of the reversal of temporary differences and carryforwards, taxable income in carryback years and tax planning strategies. In estimating taxes, we assess the relative merits and risks of the appropriate tax treatment of transactions taking into account statutory, judicial, and regulatory guidance.

As of December 31, 2021, we concluded it is more likely than not we will not generate sufficient taxable income within the allowable carryforward periods to realize any of our net deferred tax assets, and fully reserved for such assets as of December 31, 2021. In reaching this conclusion, we primarily considered forecasts of future taxable losses. As of December 31, 2021 and 2020, we had a valuation allowance of $87.5 million and $88.8 million, respectively, on our deferred tax assets.

The ability to recognize the remaining deferred tax assets that continue to be subject to a valuation allowance is evaluated on a quarterly basis to determine if there are any significant events that would affect the ability to utilize those deferred tax assets. Our estimate of future taxable income or losses is based on internal projections that consider historical performance, assumptions on future performance and external data. If events are identified that affect our ability to utilize our deferred tax assets, or if additional deferred tax assets are generated, we update our analysis to determine if an increase to a valuation allowance is required. Such an increase could have a material adverse effect on our financial condition and results of operations. Conversely, better than expected results and continued positive results and trends could result in a decrease to a valuation allowance, and any such decreases could have a material positive effect on our financial condition and results of operations.

See additional discussion in Note 18 of the Consolidated Financial Statements included in Item 8 of this Report.

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Non-GAAP Financial Measures

To supplement our financial information presented in accordance with GAAP, we are providing non-GAAP measures of certain financial performance. These non-GAAP measures include Consolidated EBITDA, Consolidated Adjusted EBITDA, RC Segment EBITDA, RC Segment Adjusted EBITDA, APT Segment EBITDA and APT Segment Adjusted EBITDA. We have included non-GAAP measures because management believes that they help to facilitate period to period comparisons of our operating results. We believe the non-GAAP measures provide useful information to both management and users of the financial statements by excluding certain expenses, gains and losses that may not be indicative of core operating results and business outlook. Management uses these non-GAAP measures in evaluating the performance of our business.

These non-GAAP measures are not in accordance with, or an alternative to, measures prepared in accordance with GAAP and may be different from non-GAAP measures used by other companies. In addition, these non-GAAP measures are not based on any comprehensive set of accounting rules or principles. These measures should only be used to evaluate our results of operations in conjunction with the corresponding GAAP measures.

We define Consolidated EBITDA as net income adjusted for the impact of the following items that are either non-cash or that we do not consider representative of our ongoing operating performance: depreciation, amortization, depletion, accretion, amortization of upfront customer consideration that was recorded as a component of the Marshall Mine Acquisition ("Upfront Customer Consideration"), interest expense, net and income tax expense. We define Consolidated Adjusted EBITDA as Consolidated EBITDA, reduced by the non-cash impacts of equity earnings from equity method investments, gain on change in estimate of asset retirement obligations, gain on extinguishment of debt and gain on customer settlement, and increased by cash distributions from equity method investments and impairment of long-lived assets. Because Consolidated Adjusted EBITDA omits certain non-cash items, we believe that the measure is less susceptible to variances that affect our operating performance.

We define APT Segment EBITDA (loss) as APT Segment operating loss adjusted for the impact of the following items that are either non-cash or that we do not consider representative of our ongoing operating performance: depreciation, amortization, depletion, accretion, amortization of Upfront Customer Consideration and interest expense, net. We define APT Segment Adjusted EBITDA (loss) as APT Segment EBITDA (loss), reduced by gain on customer settlement, gain on change in estimate of asset retirement obligation, gain on extinguishment of debt and gain on customer settlement, and increased by impairment of long-lived assets.

We define RC Segment EBITDA as RC Segment operating income adjusted for the impact of the following items that are either non-cash or that we do not consider representative of our ongoing operating performance: depreciation, amortization, depletion, accretion and interest expense. We define RC Segment Adjusted EBITDA as RC Segment EBITDA, reduced by the non-cash impact of equity earnings from equity method investments and gain on extinguishment of debt, and increased by cash distributions from equity method investments.

When used in conjunction with GAAP financial measures, we believe these non-GAAP measures are supplemental measures of operating performance that explain our operating performance for our period to period comparisons and against our competitors' performance. Generally, we believe these non-GAAP measures are less susceptible to variances that affect our operating performance results.

With the exception of extinguishment of debt, gain on change in estimate, asset retirement obligation, impairment on long-lived assets and gain on settlement, the adjustments to Consolidated Adjusted EBITDA and APT Segment Adjusted EBITDA in future periods are generally expected to be similar. These non-GAAP measures have limitations as analytical tools and should not be considered in isolation or as a substitute for analyzing our results as reported under GAAP.

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Reconciliation of Net income (loss) to Consolidated EBITDA (Loss) and Consolidated Adjusted EBITDA

The following table reconciles net income (loss), our most directly comparable as-reported financial measure calculated in accordance with GAAP, to Consolidated EBITDA (Loss) and Consolidated Adjusted EBITDA. A reconciliation of RC Segment EBITDA, RC Segment Adjusted EBITDA, APT Segment EBITDA and APT Segment Adjusted EBITDA to our most directly comparable as-reported financial measure calculated in accordance with GAAP is included below following the discussion of the results of each respective segment.

Business Segments

As of December 31, 2021, we have two reportable segments, RC and APT.

The business segment measurements provided to and evaluated by our chief operating decision maker are computed in accordance with the principles listed below:

•The accounting policies of the operating segments are the same as those described in the summary of significant accounting policies except as described below.

•Segment revenues include equity method earnings and losses from our equity method investments.

•Segment operating income (loss) includes segment revenues, gains related to sales of equity method investments and allocation of certain "Corporate general and administrative expenses," which include Payroll and benefits, Legal and professional fees, General and administrative, and Depreciation, amortization, depletion and accretion.

•RC segment operating income includes interest expense directly attributable to the RC segment.

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The principal products and services of our segments are described in Item 1 of this Report. The following table presents our operating segment results for the years ended December 31, 2021 and 2020:

(1) Included in the APT segment operating income (loss) for the years ended December 31, 2021 and 2020 was $7.4 million and $7.9 million, respectively, of depreciation, amortization, depletion and accretion expenses on mine- and plant-related long-lived assets and liabilities. Further included in the APT segment operating income (loss) for the year ended December 31, 2021 was $2.7 million related to the gain on change in estimate, asset retirement obligation. Included in the APT segment operating loss for the year ended December 31, 2020 was an impairment charge of $26.1 million offset by gain on settlement with the Former Customer of $1.1 million.

A reconciliation of segment operating income to consolidated net income is included in Note 19 of the Consolidated Financial Statements included in Item 8 of this Report.

Refined Coal

The following table provides the segment revenues of our respective equity method investments for the years ended December 31, 2021 and 2020:

For 2021, equity earnings from Tinuum Group were positively impacted by an increase in overall coal-fired power generation demand and higher production volume from coal-fired sources, which was driven by higher prices related to alternative power generation sources such as natural gas. Also, this increase was driven by higher RC facility count for the majority of 2021 compared to 2020. Further, for the year ended December 31, 2020, we recognized equity earnings from Tinuum Group equal to

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our proportionate share of Tinuum Group's net income for the period, which was less than cash distributions received for the same period.

In the fourth quarter of 2020, Tinuum Group recorded an impairment charge of $3.0 million on certain of its assets located at RC facilities and a retention accrual related to the wind down of its operations upon the expected expiration of Section 45 on December 31, 2021.

RC earnings related to M-45 license royalties increased from 2021 to 2020 as a result of an increase in the royalty rate per ton year over year offset by a reduction in RC facilities subject to the M-45 License due to the expected expiration of Section 45 on December 31, 2021.

Equity earnings from Tinuum Services increased by $0.4 million in 2021 compared to 2020 primarily as a result of recording an impairment charge of $2.9 million for year ended December 31, 2020 as well as an increase in tonnage for the RC facilities that Tinuum Services operated in 2021 compared to 2020. As of December 31, 2021 and 2020, Tinuum Services provided operating and maintenance services to zero and 22 RC facilities, respectively. Tinuum Services derived earnings from both fixed-fee arrangements as well as fees that are tied to actual RC production, as determined by the specific RC facility operating and maintenance agreement.

As discussed above, as of December 31, 2021, the Company reduced its investment in Tinuum Services in the amount of $0.7 million, which is included in the "Earnings from equity method investments" line item in the Consolidated Statement of Operations for the year ended December 31, 2021.

Outlook

As a result of the expiration of the ability to generate Section 45 tax credits after December 31, 2021, both Tinuum Group and Tinuum Services ceased operations and are in reclamation of their respective businesses. The loss of equity earnings, distributions and M-45 Royalties beginning in 2022 will have a material adverse effect on our financial condition and consolidated operating results compared to historical periods.

Reconciliation of RC Segment operating income to RC Segment EBITDA and RC Segment Adjusted EBITDA

The following table reconciles RC Segment operating income, our most directly comparable as-reported financial measure calculated in accordance with GAAP, to RC Segment EBITDA and RC Adjusted EBITDA.

Advanced Purification Technologies

APT segment operating income increased during the year ended December 31, 2021 compared to 2020 primarily due to the Impairment Charge of $26.1 million recorded for the year end December 31, 2020. Further, for the year ended December 31, 2021, consumable revenues and associated gross margin increased, driven by an increase in volume year over year, specifically related to the Supply Agreement, as well as an increase in demand for our products by our current customer base and from new customers.

During the year ended December 31, 2020, we incurred costs of $0.4 million related to sequestration of certain of our employees at our Red River plant. These costs included hazardous pay, lodging expense and other related costs for 60 days.

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Outlook

Based on current market estimates, we believe that the APT segment will continue to be affected, both positively and negatively, by power generation and the pricing of other sources, including natural gas and renewable energy, as well as weather throughout the U.S. In 2022, we expect demand from our current customers to be consistent with 2021 based on current market trends. Further, we see opportunities and are continuing to pursue diverse markets for our purification products outside of coal-fire power generation, including industrial application, water treatment plants and other end markets.

Reconciliation of APT Segment operating income (loss) to APT Segment EBITDA (loss) and APT Segment Adjusted EBITDA (loss)

The following table reconciles APT Segment income (loss), our most directly comparable as-reported financial measure calculated in accordance with GAAP, to APT Segment EBITDA (loss) and Adjusted EBITDA (loss).

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Liquidity and Capital Resources

Current Resources and Factors Affecting Our Liquidity

As of December 31, 2021, our principal future sources of liquidity include:

•$88.8 million of cash, cash equivalents and restricted cash; and

•operations of the APT segment

For the year ended December 31, 2021, our principal uses of liquidity included:

•our business operating expenses, including capital expenditures, reclamation costs, federal and state tax payments and cash severance payments; and

•payment of debt principal and interest.

During 2021, our liquidity position was positively affected primarily from cash distributions from Tinuum Group and Tinuum Services, royalty payments from Tinuum Group and borrowing availability under our line of credit with a bank ("Line of Credit"). Due to the expiration of the Section 45 tax period as of December 31, 2021 and the resultant wind down of Tinuum Group's and Tinuum Services' operations at the end of 2021, distributions from Tinuum Group will no longer be a material source of liquidity after 2021. Our line of credit expired on December 31, 2021.

Our ability to continue to generate sufficient cash flow required to meet ongoing operational needs and obligations, and make potential future dividend payments and share repurchases depends upon several factors. These include: (1) executing on our contracts and initiatives; (2) increasing our share of the market for APT consumables, including expanding our overall AC business into additional adjacent markets and improving our customer and product mix; and (3) receiving final, expected M-45 License royalty payments from Tinuum Group and distributions from Tinuum Group and Tinuum Services in 2022.

For 2022 and beyond, our primary sources of liquidity are expected to be from cash on hand and through the ongoing operations of our APT segment. We believe our existing operations and related contract volumes will continue to provide operating cost efficiencies of the Red River Plant, providing additional sources of operating cash flows in the future. Full and partial reimbursements on capital expenditures from Cabot will offset our uses of investing cash flows. As discussed above, on February 25, 2022, we received the Cabot Payment in the amount of $10.6 million, which provides a source of cash for us in 2022.

Tinuum Group and Tinuum Services Distributions

The following table summarizes the cash distributions from our equity method investments, which most significantly affected our consolidated cash flow results, for the years ended December 31, 2021 and 2020:

Cash distributions from Tinuum Group for 2021 increased by $11.9 million compared to 2020 primarily due to higher production volume driven by high competitor prices related to alternative power generation sources such as natural gas. Also, this increase was driven by higher average RC facility count for the year ended December 31, 2021 compared to 2020.

Both Tinuum Group and Tinuum Services ceased their operations as of December 31, 2021 due to the expiration of the Section 45 tax credit period as of December 31, 2021. As such, our distributions from our RC segment will substantially cease as of December 31, 2021.

During the first half of 2022, we expect to receive final cash distributions from Tinuum Group and Tinuum Services in the range of $4.0 to $5.0 million.

PPP Loan

On April 20, 2020, we entered into the PPP Loan under the PPP, evidenced by a promissory note, with BOK providing for $3.3 million in proceeds, which was funded on April 21, 2020. The PPP Loan had a maturity date of April 21, 2022. The PPP Loan

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principal was eligible for forgiveness subject to the terms of the PPP and approval by the SBA. The interest rate on the PPP Loan was 1.00%. The PPP Loan was unsecured and contains customary events of default relating to, among other things, payment defaults, making materially false and misleading representations to the SBA or BOK, or breaching the terms of the PPP Loan. The occurrence of an event of default could result in the repayment of all amounts outstanding, collection of all amounts owing from us, or filing suit and obtaining judgment against us.

On July 27, 2021, we received formal notification in the form of a letter dated July 19, 2021 from BOK that the SBA approved the forgiveness of our PPP Loan forgiveness application for the PPP Loan in the amount of $3.3 million (including accrued interest). For the year ended December 31, 2021, the Company recorded a gain on extinguishment of the PPP Loan in the amount of $3.3 million in the Consolidated Statements of Operations, which is included as a component of "Other income (expense)."

Restricted Cash

As of December 31, 2021, we had long-term restricted cash of $10.0 million as required under the Surety Agreement related to the Reclamation Contract.

Senior Term Loan

On December 7, 2018, we and ADA-ES, Inc. ("ADA"), a wholly-owned subsidiary, and certain other subsidiaries of the Company as guarantors, The Bank of New York Mellon as administrative agent, and Apollo Credit Strategies Master Fund Ltd and Apollo A-N Credit Fund (Delaware) L.P., affiliates of a beneficial owner of greater than five percent of our common stock and a related party, entered into the Senior Term Loan in the amount of $70.0 million, less original issue discount of $2.1 million. Proceeds from the Senior Term Loan were used to fund the acquisition of Carbon Solutions. We also paid debt issuance costs of $2.0 million related to the Senior Term Loan. The Senior Term Loan bore interest at a rate equal to 3-month LIBOR (subject to a 1.5% floor) + 4.75% per annum, which was adjusted quarterly to the current 3-month LIBOR rate, and interest was payable quarterly in arrears. The Senior Term Loan was secured by substantially all the assets of the Company, including the cash flows from the Tinuum Entities, but excluding our equity interests in the Tinuum entities.

On June 1, 2021 and prior to the Senior Term Loan's maturity date, we paid the remaining principal outstanding on the Senior Term Loan and all remaining accrued interest through this date. We did not incur any prepayment fees associated with the early pay-off.

Stock Repurchases and Dividends

In November 2018, our Board authorized us to purchase up to $20.0 million of our outstanding common stock under a stock repurchase program (the "Stock Repurchase Program"), which was to remain in effect until December 31, 2019 unless otherwise modified by the Board. As of November 2019, $2.9 million remained outstanding related to Stock Repurchase Program. In November 2019, the Board authorized an incremental $7.1 million to the Stock Repurchase Program and provided that it will remain in effect until all amounts are utilized or it is otherwise modified by the Board. We did not make any stock repurchases during the year ended December 31, 2021.

During the year ended December 31, 2021, we did not pay quarterly cash dividends to stockholders. We paid our most recent dividend in March 2020 of $0.25 per share.

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Line of Credit

In September 2013, ADA, as borrower, ADES, as guarantor, entered into the Line of Credit with a bank for an aggregate principal amount of $10.0 million that was secured by certain amounts due to us from certain Tinuum Group RC leases. The Line of Credit was amended 16 times from the period from December 2, 2013 through March 23, 2021, which included a reduction in the principal amount to $5.0 million in September 2018. The Line of Credit expired on December 31, 2021.

Cash Flows

Cash, cash equivalents and restricted cash increased from $35.9 million as of December 31, 2020 to $88.8 million as of December 31, 2021, an increase of $52.8 million. The following table summarizes our cash flows for the years ended December 31, 2021 and 2020, respectively:

Cash flows from operating activities

Cash flows provided by operating activities for the year ended December 31, 2021 decreased by $28.0 million compared to the year ended December 31, 2020 and the net decrease was primarily due to the following: (1) a decrease in Distributions from equity method investees, return on investment of $39.5 million year over year; (2) an increase in Earnings from equity method investments of $37.7 million year over year; (3)Impairment of long-lived assets of $26.1 million recorded in 2020; and (4) Gain on extinguishment of debt of $3.3 million recorded in 2021. Offsetting the net decrease in cash flows provided by operating activities year over year was a net change in net income of $80.7 million year over year as a result of net loss recognized for the year ended December 31, 2020.

Cash flows from investing activities

Cash flows provided by investing activities for the year ended December 31, 2021 were $44.4 million compared to cash flows used in investing activities of $7.5 million for the year ended December 31, 2020. This net increase in cash flows provided by investing activities was primarily due to increases in distributions from equity earnings in excess of cumulative earnings of $51.1 million year over year as well as proceeds from the sale of property and equipment in 2021.

Cash flows from financing activities

Cash flows used in financing activities for the year ended December 31, 2021 decreased by $10.2 million compared to the year ended December 31, 2020 primarily due to lower principal payments on the Senior Term Loan of $8.0 million. Also contributing to the decrease was a decrease year over year in dividends paid and shares repurchased of $4.9 million and $0.2 million, respectively, and a reduction in repurchases of shares of our common stock to satisfy tax withholdings of $0.3 million. Offsetting the net decrease year over year was $3.3 million of cash proceeds received in 2021 from the forgiveness of the PPP Loan.

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Material Cash Requirements

For 2022, we expect to spend $13.0 million in capital expenditures compared to $7.6 million incurred in 2021. This increase is primarily the result of forecasted improvements to the plant, which are estimated to be $7.0 million, product specific capital expenditures related to the Supply Agreement, which are estimated to be $1.0 million and routine, scheduled maintenance improvements.

As of June 30, 2021, we entered into the Retention Agreements for the purpose of retaining officers and key employees in order to maintain our current business operations, while we pursue and execute on our strategic initiatives. The total amount due at time of payment pursuant to the Retention Agreements is $2.0 million, which we expect to pay in 2022.

We intend to fund the remaining portion of the Reclamation Costs from cash on hand as well as cash generated from the Supply Agreement. We believe that as reclamation activities proceed and the related bonded amounts required under the Surety Agreement are able to be reduced, there may be an opportunity to further reduce the collateral requirement. On a normalized basis, our annual capital expenditures, exclusive of any capital specifically procured for Cabot under the Supply Agreement or capital for major improvements to the plant, are expected to average approximately $5.0 million.

We expect that our cash on hand as of December 31, 2021 will provide sufficient liquidity to fund operations for the next 12 months.

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Contractual obligations as of December 31, 2021 are as follows:

(1) Includes payments due under a capped fee contract with a third-party mining operator for reclamation of the Marshall Mine (the "Marshall Mine ARO"). Payments on this contract are due through approximately 2031. Reclamation costs related to the Marshall Mine ARO are based on a stated fee by month structure based on the initial estimate of the total costs of reclamation, which provides for certain contingencies that could increase or decrease the reclamation fee over time. The timing and amount of future payments may change from original estimates, and the Company assesses changes in estimated future amounts on a quarterly basis.

The table above also excludes our asset retirement obligation ("ARO") related to reclamation of the Five Forks Mine (the "Five Forks ARO"). As of December 31, 2021, our consolidated balance sheet reflects a liability of $3.6 million for the Five Forks ARO. The Five Forks Mine ARO was recorded at fair value. The timing and amount of payments to satisfy the Five Forks ARO are uncertain and are based on numerous factors including, but not limited to, the Five Forks Mine expected closure date.

We had no outstanding letters of credit as of December 31, 2021. We expect that our cash on hand as of December 31, 2021 will provide sufficient liquidity to fund operations for the next 12 months.

As of December 31, 2021, we had outstanding surety bonds of $24.1 million related to performance requirements under reclamation contracts associated with both the Five Forks Mine and the Marshall Mine. As of December 31, 2021, we had restricted cash of $10.0 million securing the Surety Agreement. We expect that the obligations secured by these surety bonds will be performed in the ordinary course of business and in accordance with the applicable contractual terms. To the extent that the obligations are performed, the related surety bonds should be released, and we should not have any continuing obligations. However, in the event any surety bond is called, our indemnity obligations could require us to reimburse the issuer of the surety bond.

Critical Accounting Policies and Estimates

Our significant accounting policies are discussed in Note 1 to the Consolidated Financial Statements included in Item 8 of this Report. In presenting our financial statements in conformity with GAAP, we are required to make estimates and assumptions that affect the amounts reported therein. Several of the estimates and assumptions we are required to make relate to matters that are inherently uncertain as they pertain to future events. Our estimates are based on historical experience and other assumptions believed to be reasonable under the circumstances, and we evaluate these estimates on an ongoing basis. Actual results may differ from these estimates under different assumptions or conditions.

We believe that the accounting estimates discussed below are critical to understanding our historical and future performance, as these estimates relate to the more significant areas involving management’s judgments and estimates.

Business Combinations, including asset acquisitions

We apply the acquisition method to acquisitions of both businesses and assets and allocate the purchase price to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the acquisition date. The purchase price allocation process requires us to make significant estimates and assumptions with respect to assets acquired and liabilities assumed. We believe the assumptions and estimates we make are reasonable, they are based in part on historical experience, market conditions and information obtained from management of the acquired company or group of assets and are inherently uncertain.

Examples of critical estimates in valuing certain of long-lived assets, including intangible assets, we have acquired or may acquire in the future include but are not limited to:

•future expected cash flows from revenues;

•historical and expected customer attrition rates and anticipated growth in revenues from acquired customers;

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•the acquired company’s developed technology as well as assumptions about the period of time the acquired developed technology will continue to be used in the combined company's product portfolio;

•the expected use and useful lives of the acquired assets; and

•valuation methods and discount rates used in estimating the values of the assets acquired and liabilities assumed.

In regard to the Marshall Mine Acquisition, which we accounted for as an asset acquisition, we recorded the fair value of assumed assets, which included property, plant and equipment and spare parts and assumed liabilities. In addition, we recorded other assets, including Upfront Customer Consideration and the Cabot Receivable, and a liability for the Marshall Mine ARO.

Carrying value of long-lived assets and intangibles

We review and evaluate our long-lived assets and intangibles for impairment at least annually, or more frequently when events or changes in circumstances indicate that the related carrying amounts may not be recoverable. An impairment loss is measured and recorded for long-lived assets and intangibles based on the excess of their carrying amounts over their estimated fair values. Fair value is typically determined through the use of an income approach utilizing estimates of discounted pretax future cash flows or a market approach utilizing recent transaction activity for comparable assets.

Asset Retirement Obligations

Accounting for AROs requires us to make estimates of future costs unique to a specific mining operation that we will incur to complete the reclamation and remediation work required to comply with existing laws and regulations. Any such changes in future costs, the timing of reclamation activities, scope or the exclusion of certain costs not considered reclamation and remediation costs could materially impact the amounts charged to earnings for reclamation and remediation. Additionally, future changes to environmental laws and regulations could increase the scope of reclamation and remediation work required.