Contingent Liabilities and Commitments (Notes)

3 Months Ended

Mar. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

Contingent Liabilities and Commitments

Contingent Liabilities and Commitments

Environmental Matters

We have had studies underway for many years to test some of our facilities for the presence of toxic and hazardous substances such as polychlorinated biphenyls (PCBs) and mercury to determine to what extent, if any, remediation may be necessary. We have also similarly evaluated past on-site disposal of hydrocarbons at a number of our facilities. We have worked closely with and responded to data requests from the U.S. Environmental Protection Agency (EPA) and state agencies regarding such potential contamination of certain of our sites. We are conducting environmental assessments and implementing a variety of remedial measures that may result in increases or decreases in the total estimated costs. We also have a program for monitoring certain environmental activities at our Eminence storage facility. At March 31, 2024, we had a liability of approximately $10.4 million for the expected ongoing remediation and monitoring costs, $0.7 million recorded in Accrued liabilities - Other and $9.7 million recorded in Other Long-Term Liabilities - Other on the Balance Sheet. At December 31, 2023, we had a liability of approximately $10.5 million for the expected ongoing remediation and monitoring costs, $0.6 million recorded in Accrued liabilities - Other and $9.9 million recorded in Other Long-Term Liabilities - Other on the Balance Sheet.

We have been identified as a potentially responsible party (PRP) at various Superfund and state waste disposal sites. Based on present volumetric estimates and other factors, our estimated aggregate exposure for remediation of these sites is less than $0.5 million. The estimated remediation costs for all of these sites are included in the environmental liabilities discussed above. Liability under the Comprehensive Environmental Response, Compensation and Liability Act and applicable state law can be joint and several with other PRPs. Although volumetric allocation is a factor in assessing liability, it is not necessarily determinative; thus, the ultimate liability could be substantially greater than the amounts described above.

The EPA and various state regulatory agencies routinely propose and promulgate new rules, and issue updated guidance to existing rules. These rulemakings include, but are not limited to, rules for reciprocating internal combustion engine and combustion turbine maximum achievable control technology, review and updates to the National Ambient Air Quality Standards, and rules for new and existing source performance standards for volatile organic compounds and methane. We continuously monitor these regulatory changes and how they may impact our operations. Implementation of new or modified regulations may result in impacts to our operations and increase the cost of additions to Total property, plant, and equipment, net on the Balance Sheet for both new and existing facilities in affected areas; however, due to regulatory uncertainty on final rule content and applicability timeframes, we are unable to reasonably estimate the cost of these regulatory impacts at this time.

We consider prudently incurred environmental assessment and remediation costs and the costs associated with compliance with environmental standards to be recoverable through rates. Historically, with limited exceptions, we have been permitted recovery of environmental costs, and it is our intent to continue seeking recovery of such costs through future rate filings.

Other Matters

Various other proceedings are pending against us and are considered incidental to our operations.

Summary

We have disclosed all significant matters for which we are unable to reasonably estimate a range of possible loss. We estimate that for all matters for which we are able to reasonably estimate a range of loss, including those noted above and others that are not individually significant, our aggregate reasonably possible losses beyond amounts accrued for all of our contingent liabilities are immaterial to our expected future annual results of operations, liquidity and financial position. These calculations have been made without consideration of any potential recovery from third parties.