PROPERTY, PLANT AND EQUIPMENT

A summary of changes in property, plant and equipment follows (in millions):



	Dec 31, 2010			Capital Expenditures (Depreciation)			Transfers and Retirements			Dec 31, 2011			Capital Expenditures (Depreciation)			Transfers and Retirements			Dec 31, 2012
Construction work in progress	$	1,126.3		$	135.9		$	(151.0	)	$	1,111.2		$	13.6		$	(1,122.1	)	$	2.7
Leasehold improvements	187.3			—			(4.4		)	182.9			—			0.8			183.7
Machinery and equipment	269.1			—			(17.9		)	251.2			0.3			(69.8		)	181.7
	1,582.7			135.9			(173.3		)	1,545.3			13.9			(1,191.1		)	368.1
Accumulated depreciation and amortization	(351.3		)	(42.7		)	35.8			(358.2		)	(27.0		)	68.1			(317.1		)
	$	1,231.4		$	93.2		$	(137.5	)	$	1,187.1		$	(13.1	)	$	(1,123.0	)	$	51.0



	Dec 31, 2012			Capital Expenditures (Depreciation)			Transfers and Retirements			Dec 31, 2013
Construction work in progress	$	2.7		$	—		$	(2.7	)	$	—
Leasehold improvements	183.7			—			(42.6		)	141.1
Machinery and equipment	181.7			—			(17.7		)	164.0
	368.1			—			(63.0		)	305.1
Accumulated depreciation and amortization	(317.1		)	(23.3		)	43.2			(297.2		)
	$	51.0		$	(23.3	)	$	(19.8	)	$	7.9

Paducah GDP

As noted in Note 4, "Transition Charges", USEC incurred a charge to cost of sales of $19.8 million in 2013 in connection with the ceasing of enrichment at the Paducah GDP and the related retirements of property, plant and equipment used in the enrichment process. Beginning in the fourth quarter of 2012, the expected productive life of property, plant and equipment at the Paducah GDP was reduced from the lease term ending June 2016 to an accelerated basis ending December 2014. In addition, beginning in the third quarter of 2012, costs that would have been previously treated as construction work in progress are treated similar to maintenance and repair costs because of the shorter expected productive life of the Paducah GDP. The expected productive life of the Paducah GDP was further reduced following the ceasing of enrichment at the end of May 2013.

American Centrifuge

USEC is working to deploy the American Centrifuge technology at the ACP in Piketon, Ohio. In the fall of 2011, instead of moving forward with a conditional commitment for a loan guarantee for the American Centrifuge project through the DOE Loan Guarantee Program, DOE proposed a two-year cost share RD&D Program for the American Centrifuge project. USEC, its subsidiary American Centrifuge Demonstration, LLC (“ACD”) and DOE entered into a cooperative agreement for the RD&D Program on June 12, 2012. Additional details are provided in Note 20 under "American Centrifuge - Project Funding." Beginning in the fourth quarter of 2011, as a result of the shift in focus of the American Centrifuge project, USEC began spending on the American Centrifuge technology at reduced levels with activities concentrating on development and demonstration. As a result, all project costs incurred since the start of the fourth quarter of 2011 have been expensed, including interest expense that previously would have been capitalized.

Based on USEC’s internal analysis concluded as part of its annual assessment, as of December 31, 2012, USEC expensed $1.1 billion of previously capitalized costs related to the American Centrifuge project. This included previously capitalized costs related to property, plant and equipment (including construction work in progress) of $1,075.6 million, prepayments made to suppliers of $9.9 million and deferred financing costs related to the DOE loan guarantee program of $6.7 million that were previously capitalized during the period 2007 through 2011.

Although USEC continues to effectively execute the RD&D Program, the expense of previously capitalized costs in 2012 was based on USEC's assessment of its ability to recover the full amount of this prior capital investment. In light of the significant remaining capital needed to deploy the ACP and USEC’s view of its anticipated cash flow from operations available to finance the ACP given its other anticipated cash needs during that period, USEC anticipates that its ultimate share of the ownership of the ACP will likely be reduced, which affects USEC’s likelihood of recovering this past investment. This expense of previously capitalized costs does not affect any future capital investment in the ACP. USEC would anticipate that capitalization of amounts related to the ACP would resume if and when commercial plant deployment resumes.

On June 12, 2012, USEC, through its subsidiary ACD, entered into a contract with DOE to transfer to DOE title to the centrifuge machines and equipment produced or acquired under the RD&D Program. The transferred property included specified existing machines and equipment having a cost of $44.6 million that were transferred in the second quarter of 2012, and the machines and equipment that are produced or acquired under the cooperative agreement.