4.Property, Plant and Equipment

Property, plant and equipment (“PP&E”) is stated at cost, less accumulated depreciation. Depreciation is calculated on a straight-line basis over the estimated useful service life of the asset.

PP&E consists of the following:

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Accrued PP&E additions totaled $9.1 million and $13.1 million at September 30, 2024 and December 31, 2023, respectively.

Abandoned Projects

During the three and nine months ended September 30, 2024, we recorded $0.1 million and $0.8 million, respectively, in abandoned project expense related to abandoned projects and the write-off of permits for water handling facilities and right-of-way easements that either expired prior to use or that we no longer planned to use for future projects.

During the nine months ended September 30, 2023, we recorded $0.1 million in abandoned project expense. Abandoned project expense is recorded in “Other Operating (Income) Expense, Net” in the condensed consolidated statements of operations.

Assets Sold

During the three months ended September 30, 2023, we received cash consideration of $20.1 million for the sale of certain assets. We recorded a gain of $2.6 million, which is included in “Other Operating (Income) Expense, Net” in the condensed consolidated statements of operations for the three and nine months ended September 30, 2023.

Abandoned Assets

During the three months ended September 30, 2023, management determined a stand-alone produced water handling facility was no longer economically beneficial to the operations of the Company and should be shut-in and taken out of service. Accordingly, we removed the costs and the associated accumulated depreciation and recognized a $1.2 million charge for the remaining book value of the asset. This charge is included in “Abandoned Well Costs” in the condensed consolidated statements of operations for the three and nine months ended September 30, 2023.