3. Property, Plant and Equipment

Assets Held for Sale: At June 30, 2017, assets classified as “held for sale” totaled $340 million related to our enhanced oil recovery assets in the Permian Basin that were comprised primarily of net property, plant and equipment and allocated goodwill of $25 million. In addition, associated liabilities amounting to $13 million were reported in Accrued liabilities in the Consolidated Balance Sheet. See Note 12, Subsequent Event. At December 31, 2016, we classified as held for sale certain non-core acreage, onshore United States amounting to $106 million.

Capitalized Exploratory Well Costs: The following table discloses the net changes in capitalized exploratory well costs pending determination of proved reserves during the six months ended June 30, 2017 (in millions):

Balance at January 1, 2017	$	597
Additions to capitalized exploratory well costs pending the determination of proved reserves		55
Reclassifications to wells, facilities and equipment based on the determination of proved reserves		(165	)
Balance at June 30, 2017	$	487

Reclassifications to wells, facilities and equipment based on the determination of proved reserves resulted from sanction of the first phase of development for the Liza Field, offshore Guyana. Capitalized exploratory well costs capitalized for greater than one year following completion of drilling were $415 million at June 30, 2017 and primarily related to:

Ghana: Approximately 65% of the capitalized well costs in excess of one year relates to our Deepwater Tano/Cape Three Points license (Hess 50%), offshore Ghana. The government of Côte d’Ivoire has challenged the maritime border between it and the country of Ghana, which includes a portion of our Deepwater Tano/Cape Three Points license. We are unable to proceed with development of this license until there is a resolution of this matter, which may also impact our ability to develop the license. The International Tribunal for Law of the Sea is expected to render a final ruling on the maritime border dispute in September 2017. Under terms of our license and subject to resolution of the border dispute, we have declared commerciality for four discoveries, including the Pecan Field in March 2016, which would be the primary development hub for the block. Following a favorable outcome of the border dispute, we will have ten months to submit a plan of development to the Ghanaian government. Front-end engineering studies and other development planning is progressing.

Gulf of Mexico: Approximately 25% of the capitalized well costs in excess of one year relates to an appraisal well in the northern portion of the Shenzi Field (Hess 28%) in the Gulf of Mexico, where hydrocarbons were encountered in the fourth quarter of 2015. The operator is evaluating plans for developing this area of the field.

JDA: Approximately 10% of the capitalized well costs in excess of one year relates to the JDA in the Gulf of Thailand (Hess 50%) where hydrocarbons were encountered in three successful exploration wells drilled in the western part of Block A-18. The operator is currently evaluating results and formulating future drilling plans in the area.