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Landfill and Environmental Remediation Liabilities | 6 Months Ended
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Jun. 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):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | June 30, 2020 | ​ | December 31, 2019
​ | ​ | ​ | ​ | ​ | Environmental | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Environmental | ​ | ​ | ​
​ |  | Landfill |  | Remediation |  | Total |  | Landfill |  | Remediation |  | Total
Current (in accrued liabilities) |  | $ | 108 | ​ | $ | 26 | ​ | $ | 134 | ​ | $ | 138 | ​ | $ | 27 | ​ | $ | 165
Long-term | ​ |  | 1,814 | ​ |  | 216 | ​ |  | 2,030 |  |  | 1,717 | ​ |  | 213 | ​ |  | 1,930
​ |  | $ | 1,922 | ​ | $ | 242 | ​ | $ | 2,164 | ​ | $ | 1,855 | ​ | $ | 240 | ​ | $ | 2,095
​ The changes to landfill and environmental remediation liabilities for the six months ended June 30, 2020 are reflected in the table below (in millions):
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Environmental
​ |  | Landfill |  | Remediation
December 31, 2019 | ​ | $ | 1,855 | ​ | $ | 240
Obligations incurred and capitalized | ​ |  | 40 |  |  | —
Obligations settled | ​ |  | (47) |  |  | (11)
Interest accretion | ​ |  | 49 |  |  | 1
Revisions in estimates and interest rate assumptions (a) (b) | ​ |  | 27 |  |  | 12
Acquisitions, divestitures and other adjustments | ​ |  | (2) |  |  | —
June 30, 2020 | ​ | $ | 1,922 | ​ | $ | 242
(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 June 30, 2020.
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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