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Landfill and Environmental Remediation Liabilities | 12 Months Ended
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Dec. 31, 2020
Landfill and Environmental Remediation Liabilities |
Landfill and Environmental Remediation Liabilities | 4. Landfill and Environmental Remediation Liabilities Liabilities for landfill and environmental remediation costs as of December 31 are presented in the table below (in millions):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | 2020 | ​ | 2019
​ | ​ | ​ | ​ | ​ | Environmental | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Environmental | ​ | ​ | ​
​ |  | Landfill |  | Remediation |  | Total |  | Landfill |  | Remediation |  | Total
Current (in accrued liabilities) |  | $ | 138 | ​ | $ | 26 | ​ | $ | 164 | ​ | $ | 138 | ​ | $ | 27 | ​ | $ | 165
Long-term | ​ |  | 2,018 | ​ |  | 204 | ​ |  | 2,222 |  |  | 1,717 | ​ |  | 213 | ​ |  | 1,930
​ |  | $ | 2,156 | ​ | $ | 230 | ​ | $ | 2,386 | ​ | $ | 1,855 | ​ | $ | 240 | ​ | $ | 2,095
​ The changes to landfill and environmental remediation liabilities for the year ended December 31, 2020 are reflected in the table below (in millions):
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Environmental
​ |  | Landfill |  | Remediation
December 31, 2019 | ​ | $ | 1,855 | ​ | $ | 240
Obligations incurred and capitalized | ​ |  | 83 |  |  | —
Obligations settled | ​ |  | (103) |  |  | (23)
Interest accretion | ​ |  | 103 |  |  | 2
Revisions in estimates and interest rate assumptions (a) (b) | ​ |  | (27) |  |  | 11
Acquisitions, divestitures and other adjustments (c) | ​ |  | 245 |  |  | —
December 31, 2020 | ​ | $ | 2,156 | ​ | $ | 230
(a) | The amount reported for our landfill liabilities includes a reduction of $104 million related to the change in inflation rate from 2.5% to 2.25% as of December 31, 2020, of which $26 million was an immediate reduction to amortization expense. This reduction to landfill liabilities was partially offset by (i) an increase of $69 million primarily from changes in the timing and amount of costs as well as changes in estimates of remaining airspace and (ii) an increase of $8 million due to a business decision to close one of our landfills, which resulted in the acceleration of the expected timing of capping, closure and post-closure activities. This business decision also resulted in an impairment that is discussed in Note 12.
(b) | The amount reported for our environmental remediation liabilities includes an increase of $9 million due to a decrease in the risk-free discount rate used to measure our liabilities from 1.75% at December 31, 2019 to 1.00% at December 31, 2020.
(c) | The amount reported for our landfill liabilities includes (i) $261 million related to our acquisition of Advanced Disposal offset by (ii) a reduction of $17 million for the sale of certain landfills to GFL Environmental Inc. (“GFL Environmental”) in connection with the Advanced Disposal acquisition. These items are discussed further in Note 18.
Our recorded liabilities as of December 31, 2020 include the impacts of inflating certain of these costs based on our expectations of the timing of cash settlement and of discounting certain of these costs to present value. Anticipated payments of currently identified environmental remediation liabilities, as measured in current dollars, are $26 million in 2021, $48 million in 2022, $40 million in 2023, $33 million in 2024, $12 million in 2025 and $61 million thereafter. At several of our landfills, we provide financial assurance by depositing cash into restricted trust funds or escrow accounts for purposes of settling final capping, closure, post-closure and environmental remediation obligations. Generally, these trust funds are established to comply with statutory requirements and operating agreements. See Notes 17 and 19 for additional information related to these trusts.

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