v3.26.1
Landfill and Environmental Costs
 6 Months Ended
Jun. 30, 2026
Environmental Remediation Obligations [Abstract]  
LANDFILL AND ENVIRONMENTAL COSTS LANDFILL AND ENVIRONMENTAL COSTS
As of June 30, 2026, we owned or operated 208 active landfills, and we had post-closure responsibility for 125 closed landfills.
Accrued Landfill and Environmental Costs
A summary of accrued landfill and environmental costs as of June 30, 2026 and December 31, 2025 follows:
20262025
Landfill final capping, closure and post-closure liabilities$2,369 $2,313 
Environmental remediation429 443 
Total accrued landfill and environmental costs2,798 2,756 
Less: current portion(156)(148)
Long-term portion$2,642 $2,608 
Final Capping, Closure and Post-Closure Costs
The following table summarizes the activity in our asset retirement obligation liabilities, which includes liabilities for final capping, closure and post-closure, for the six months ended June 30, 2026 and 2025:
20262025
Asset retirement obligation liabilities, beginning of year$2,313 $2,144 
Non-cash additions34 39 
Acquisitions, net of divestitures and other adjustments6 1 
Asset retirement obligation adjustments(17)4 
Payments(27)(21)
Accretion expense60 57 
Asset retirement obligation liabilities, end of period2,369 2,224 
Less: current portion(96)(79)
Long-term portion$2,273 $2,145 
We review annually, in the fourth quarter, and update as necessary, our estimates of asset retirement obligation liabilities. However, if there are significant changes in the facts and circumstances related to a site during the year, we will update our assumptions prospectively in the period that we know all the relevant facts and circumstances and make adjustments as appropriate.
Landfill Operating Expenses
In the normal course of business, we incur various operating costs associated with environmental compliance. These costs include, among other things, leachate treatment and disposal, methane gas and groundwater monitoring, systems maintenance, interim cap maintenance, costs associated with the application of daily cover materials, and the legal and administrative costs of ongoing environmental compliance. These costs are expensed as cost of operations in the periods in which they are incurred.
Environmental Remediation Liabilities
We accrue for remediation costs when they become probable and can be reasonably estimated. There can sometimes be a range of reasonable estimates of the costs associated with remediation of a site. In these cases, we use the amount within the range that constitutes our best estimate. If no amount within the range appears to be a better estimate than any other, we use the amount that is at the low end of such range. It is reasonably possible that we will need to adjust the liabilities recorded for remediation to reflect the effects of new or additional information, to the extent such information impacts the costs, timing or duration of the required actions. If we used the reasonably possible high ends of our ranges, our aggregate potential remediation liability as of June 30, 2026 would be approximately $276 million higher than the amount recorded. Future changes in our estimates of the cost, timing or duration of the required actions could have a material adverse effect on our consolidated financial position, results of operations and cash flows.
The following table summarizes the activity in our environmental remediation liabilities for the six months ended June 30, 2026 and 2025:
20262025
Environmental remediation liabilities, beginning of year$443 $447 
Payments(26)(19)
Accretion expense (non-cash interest expense)8 9 
Acquisitions, net of divestitures and other adjustments4 21 
Environmental remediation liabilities, end of period429 458 
Less: current portion(60)(62)
Long-term portion$369 $396 
West Lake Landfill Superfund Site. Our subsidiary Bridgeton Landfill, LLC is one of several currently designated Potentially Responsible Parties for the West Lake Landfill Superfund site (West Lake) in Missouri. On September 27, 2018, the United States Environmental Protection Agency (EPA) issued a Record of Decision Amendment for West Lake that includes a total undiscounted cost estimate of $229 million over a four to five year design and construction timeline. On March 11, 2019, the EPA issued special notice letters under the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) to Bridgeton Landfill, LLC and the other currently designated Potentially Responsible Parties to initiate negotiations to implement the remedy. On January 17, 2025, the EPA issued an Explanation of Significant Differences (ESD) applying the prior Record of Decision Amendment to an increased number of acres at the site found to contain radiologically-impacted material. The ESD includes a revised undiscounted cost estimate of $392 million. At this time we are neither able to predict the final design of that remedy, nor estimate how much of the future response costs of the site our subsidiary may agree or be required to pay. During any subsequent administrative proceedings or litigation, our subsidiary will vigorously contest liability for the costs of remediating radiologically-impacted materials generated on behalf of the federal government during the Manhattan Project and delivered to the site by an Atomic Energy Commission licensee and its subcontractor. However, subsequent events related to remedy design, divisibility, or allocation may require us to modify our expected remediation liability.