Ducommun DCO West Covina, California — Reserve for estimated liability

Structural Systems also faces liability as a potentially responsible party for hazardous waste disposed at landfills located in Casmalia and West Covina, California. Structural Systems and other companies and government entities have entered into consent decrees with respect to these landfills with the United States Environmental Protection Agency and/or California environmental agencies under which certain investigation, remediation and maintenance activities are being performed. Based on currently available information, we preliminarily estimate that the range of our future liabilities in connection with the landfill located in West Covina, California is between $0.4 million and $3.1 million. We have established an accrual for the estimated liability in connection with the West Covina landfill, which had a balance of $0.4 million as of both July 4, 2026 and December 31, 2025, which is reflected in other long-term liabilities on our unaudited condensed consolidated balance sheets. We anticipate an updated estimate will be available over the next 12 to 24 months however, and will update our accrual for the estimated liability at that time, if needed. Our ultimate liability in connection with these matters will depend upon a number of factors, including changes in existing laws and regulations, the design and cost of construction, operation and maintenance activities related to a final remedy, and the allocation of liability among potentially responsible parties.