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 $31.2 million and $13.1 million at June 30, 2024 and December 31, 2023, respectively.

Abandoned Projects

During the first quarter of 2024, we recorded $0.7 million in abandoned project expense related to 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 second quarter of 2023, we recorded $0.1 million in abandoned project expense. Abandoned project expense is recorded in “Other Operating Expense (Income), Net” in the condensed consolidated statements of operations.

Assets Held for Sale

During the second quarter of 2023, management entered into a letter of intent with a third party to sell certain of our assets. These assets met the criteria for classification as assets held for sale as of June 30, 2023, and we received a $1.8 million deposit related to the anticipated sale. We closed the sale of these assets during the third quarter of 2023.