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Landfill and Environmental Remediation Liabilities | 9 Months Ended
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Sep. 30, 2020
Landfill and Environmental Remediation Liabilities |
Landfill and Environmental Remediation Liabilities | 2. Landfill and Environmental Remediation Liabilities Liabilities for landfill and environmental remediation costs are presented in the table below (in millions):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | September 30, 2020 | ​ | December 31, 2019
​ | ​ | ​ | ​ | ​ | Environmental | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Environmental | ​ | ​ | ​
​ |  | Landfill |  | Remediation |  | Total |  | Landfill |  | Remediation |  | Total
Current (in accrued liabilities) |  | $ | 102 | ​ | $ | 27 | ​ | $ | 129 | ​ | $ | 138 | ​ | $ | 27 | ​ | $ | 165
Long-term | ​ |  | 1,826 | ​ |  | 211 | ​ |  | 2,037 |  |  | 1,717 | ​ |  | 213 | ​ |  | 1,930
​ |  | $ | 1,928 | ​ | $ | 238 | ​ | $ | 2,166 | ​ | $ | 1,855 | ​ | $ | 240 | ​ | $ | 2,095
​ The changes to landfill and environmental remediation liabilities for the nine months ended September 30, 2020 are reflected in the table below (in millions):
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Environmental
​ |  | Landfill |  | Remediation
December 31, 2019 | ​ | $ | 1,855 | ​ | $ | 240
Obligations incurred and capitalized | ​ |  | 61 |  |  | —
Obligations settled | ​ |  | (75) |  |  | (17)
Interest accretion | ​ |  | 75 |  |  | 1
Revisions in estimates and interest rate assumptions (a) (b) | ​ |  | 30 |  |  | 14
Acquisitions, divestitures and other adjustments (c) | ​ |  | (18) |  |  | —
September 30, 2020 | ​ | $ | 1,928 | ​ | $ | 238
(a) | The amount reported for our landfill liabilities includes (i) a $10 million increase in estimated construction costs for capping at certain landfills 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 9.
(b) | The amount reported for our environmental remediation liabilities includes an increase of $12 million due to a decrease in the risk-free discount rate used to measure our liabilities from 1.75% at December 31, 2019 to 0.75% at September 30, 2020.
(c) | The amount reported for landfill liabilities includes the reclassification of $17 million to accrued liabilities in our Condensed Consolidated Balance Sheet related to certain landfills classified as held for sale as of September 30, 2020 in connection with the sale of the landfills to GFL Environmental Inc. The divestiture is directly related to the
| Advanced Disposal, Inc. (“Advanced Disposal”) acquisition. These transactions are discussed further in Notes 8 and 14.
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 Note 13 for additional information related to these trusts.

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