Note 5 - Natural Gas Properties & Other Property, Plant, and Equipment

As of December 31, 2025 and 2024, accumulated depreciation, depletion, and amortization for developed natural gas properties was $825.7 million and $697.0 million, respectively. Depreciation, depletion, and amortization expense for developed natural gas properties was $128.7 million, $188.7 million, and $196.1 million for the years ended December 31, 2025, 2024, and 2023 respectively.

Midstream assets consisted of the following:

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Depreciation expense on midstream assets was $6.4 million, $6.9 million, and $7.5 million for the years ended December 31, 2025, 2024, and 2023, respectively.

Other property, plant, and equipment consisted of the following:

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Depreciation expense for other property, plant, and equipment was $43.3 million, $43.7 million, and $37.1 million for the years ended December 31, 2025, 2024, and 2023, respectively. During the year ended December 31, 2025, the Company received proceeds on the sale of other properties and equipment of $6.9 million, which included the sale of the Bridgeport field office of $5.5 million, less transaction costs of $0.4 million, and recognized a loss on sale of these properties and equipment of $1.8 million, which is included in the gains (losses) on sales of assets, net in the consolidated statements of operations. During the year ended December 31, 2024, the Company received proceeds on the sale of other properties of $5.0 million, and recognized a gain on sale of these properties of $3.6 million, which is included in the gains (losses) on sales of assets, net in the consolidated statements of operations. During the year ended December 31, 2023, the Company received proceeds on the sale of other properties of $6.7 million, and recognized a gain on sale of these properties of $2.2 million, which is included in the gains (losses) on sales of assets, net, in the consolidated statements of operations.

Write-Off of ERP System

During the year ended December 31, 2025, the Company was actively implementing a new enterprise resource planning (“ERP”) system and had capitalized $6.9 million in software costs. However, during the third quarter of 2025, the Company decided to

discontinue implementation of this ERP system and wrote off $5.6 million of capitalized software costs, which is included in other operating expense in the consolidated statements of operations, as the system was determined to no longer align with the Company’s operational and strategic needs. The Company is in the process of implementing a new ERP system that better supports its business processes and long-term objectives.

Intangible Assets

The Company’s intangible assets, reflected within other noncurrent assets on the consolidated balance sheets, represent customer listings, which are amortized using the straight-line method based on its estimated useful life of 3 years. The customer listings were acquired in 2023 for $1.8 million, and amortization on these listings was $0.6 million for both the years ended December 31, 2025 and 2024, and $0.3 million for the year ended December 31, 2023. As of December 31, 2025, the estimated future aggregate amortization expense for intangible assets is expected to be $0.3 million in 2026.