Exhibit 10.1

FIRST AMENDMENT TO FOURTH AMENDED AND RESTATED CREDIT AGREEMENT

This FIRST AMENDMENT TO FOURTH AMENDED AND RESTATED CREDIT AGREEMENT dated as of
June 1, 2012 (this “Amendment”), is by and among USEC INC., a Delaware
corporation (“Holdings”), UNITED STATES ENRICHMENT CORPORATION, a Delaware
corporation (together with Holdings, the “Borrowers”), those Lenders under the
Credit Agreement referred to below which are signatories to this Amendment, and
JPMORGAN CHASE BANK, N.A., as Administrative and Collateral Agent (the
“Administrative Agent”), and amends that certain Fourth Amended and Restated
Credit Agreement dated as of March 13, 2012 (the “Existing Credit Agreement”
and, as amended by this Amendment, the “Credit Agreement”), among the Borrowers,
the Lenders party thereto, the Administrative Agent and the other financial
institutions named therein as “agents”, “bookrunners” and “arrangers”.
 
WHEREAS, the Borrowers have requested that the Administrative Agent and the
Lenders amend certain provisions of the Existing Credit Agreement as more fully
described herein; and
 
WHEREAS, the Administrative Agent and the Lenders party to this Amendment are
willing to amend the Existing Credit Agreement as provided herein, all subject
to the terms and conditions set forth herein;
 
NOW, THEREFORE, in consideration of the foregoing and the agreements contained
herein, the parties hereto hereby agree as follows:
 
1. Capitalized Terms.  Capitalized terms used herein which are defined in the
Existing Credit Agreement have the same meanings herein as therein, except to
the extent that such meanings are amended hereby.
 
2. Amendment to Section 6.11 of Existing Credit Agreement.  Subject to the
satisfaction of the terms and conditions set forth in Section 4 hereof and in
reliance on the representations set forth in Section 3 hereof, Section 6.11 of
the Existing Credit Agreement is hereby amended by deleting clauses (c) and (d)
of Section  6.11 in their entirety and replacing such clauses with the following
new clauses (c) and (d):
 
“(c)           (i) the Borrowers shall be permitted to make ACP Expenditures
during the period commencing on June 1, 2012 and continuing to and including the
earlier of June 15, 2012 and the ACP Grant Start Date in an aggregate amount not
to exceed $6,000,000, provided that on each of June 8, 2012 and June 15, 2012
(1) the Borrowers shall deliver to the Administrative Agent and the Lenders a
report setting forth (x) the estimated amount of ACP Expenditures made during
the period from June 1, 2012 through the Business Day immediately prior to the
date of such report and (y) the status of the Borrowers’ negotiations with the
DOE regarding the definitive documentation relating to the ACP Grant, and (2)
promptly following the delivery of each such report at the request of the
Administrative Agent or any Lender, the Borrowers shall make a Financial Officer
and other appropriate officers of the Borrowers available to participate in a
teleconference with the Administrative Agent and the Lenders to discuss the
Borrowers’ ACP Expenditures and the status of the Borrowers’ negotiations with
the DOE regarding the definitive documentation relating to the ACP Grant, and
(ii) if the Borrowers shall not have entered into definitive binding
documentation with the DOE with respect to the ACP Grant on or before June 15,
2012, then (A) the Borrowers shall not be permitted to make any further ACP
Expenditures during the month of June 2012 and (B) the Borrowers shall not be
permitted to make ACP Expenditures during any month commencing on or after July
1, 2012 in excess of $1,000,000 per month;”
 
“(d)           if the Borrowers shall have entered into definitive binding
documentation with the DOE with respect to an ACP Grant, then, from and after
the ACP Grant Start Date, the Borrowers shall be permitted to make ACP
Expenditures to the extent that, as of any date, the aggregate amount of ACP
Expenditures made by the Borrowers from June 1, 2012 through such date does not
exceed 110% of the aggregate amount of ACP Expenditures anticipated to be made
by the Borrowers through the end of the month in which such date occurs pursuant
to the budget included in the definitive documentation between the Borrowers and
the DOE relating to the ACP Grant; provided that (x) if, at any time, the
difference between (1) 80% of the aggregate amount of ACP Expenditures made by
the Borrowers after June 1, 2012 (plus, if the Borrowers shall not have received
cash proceeds (including the release of cash pledged to secure (x) surety bonds,
(y) letters of credit or (z) other like instruments) equal to or greater than
$43,000,000 pursuant to the DOE SWU Purchase Agreement, the aggregate amount of
DOE SWU Purchase Expenditures less the amount of any such cash proceeds
(including the release of cash pledged to secure (x) surety bonds, (y) letters
of credit or (z) other like instruments) actually received) and (2) the
aggregate amount of ACP Grant Proceeds actually received by the Borrowers after
the ACP Grant Start Date, exceeds $50,000,000, or (y) if the Borrowers fail to
receive any ACP Grant Proceeds on or before the date that is three months after
the ACP Grant Start Date, the Borrowers shall not make any further ACP
Expenditures unless and until such time as the Borrowers have received ACP Grant
Proceeds in an amount sufficient to cause the difference between (A) 80% of the
aggregate amount of ACP Expenditures made by the Borrowers after June 1, 2012
(plus, if the Borrowers shall not have received cash proceeds (including the
release of cash pledged to secure (x) surety bonds, (y) letters of credit or (z)
other like instruments) equal to or greater than $43,000,000 pursuant to the DOE
SWU Purchase Agreement, the aggregate amount of DOE SWU Purchase Expenditures
less the amount of any such cash proceeds (including the release of cash pledged
to secure (x) surety bonds, (y) letters of credit or (z) other like instruments)
actually received) and (B) the aggregate amount of ACP Grant Proceeds actually
received by the Borrowers after the ACP Grant Start Date, to be less than
$50,000,000; provided, further that in no event shall (I) the aggregate amount
of ACP Expenditures made by the Borrowers from and after June 1, 2012 exceed
$375,000,000 and (II) the aggregate amount of ACP Expenditures made by the
Borrowers from and after June 1, 2012 for which the Borrowers are not entitled
to receive reimbursement in the form of ACP Grant Proceeds exceed $75,000,000;”
 
3. No Default; Representations and Warranties, etc.  Each of the Borrowers
represents and warrants to the Lenders and the Administrative Agent that as of
the date hereof (a) the representations and warranties of the Credit Parties
contained in Article III of the Existing Credit Agreement are true and correct
in all material respects as of the date hereof as if made on such date (except
to extent that such representations and warranties expressly relate to an
earlier date, in which case they shall be true and correct in all material
respects as of such date); (b) the Borrowers are in compliance in all material
respects with all of the terms and provisions set forth in the Credit Agreement
and the other Financing Documents to be observed or performed by them
thereunder; (c) no Default or Event of Default has occurred and is continuing;
and (d) the execution, delivery and performance by the Borrowers of this
Amendment (i) have been duly authorized by all necessary corporate and, if
required, shareholder action on the part of the Borrowers, (ii) will not violate
any applicable law or regulation applicable to the Borrowers or the
organizational documents of any Borrower, (iii) will not violate or result in a
default under any indenture, agreement or other instrument binding on any
Borrower or any of its assets and (iv) do not require any consent, waiver or
approval of or by any Person (other than the Administrative Agent and the
Lenders) which has not been obtained.
 
4. Conditions Precedent.  The effectiveness of this Amendment shall be
conditioned upon the satisfaction of the following conditions precedent:
 
(a) Counterparts of Amendment:  The Administrative Agent shall have received
counterparts of this Amendment signed on behalf of the Borrowers and the
Required Revolving Lenders voting as a separate Class and the Required Term
Lenders voting as a separate Class and a counterpart of the Ratification of
Guarantee attached hereto signed on behalf of NAC International Inc., as
Guarantor (which counterparts may be delivered by telecopy or electronic
transmission of a pdf of a signed signature page to this Amendment or such
Ratification of Guarantee, as applicable).
 
(b) First Amendment Fee Letter:  The Borrowers shall have executed and delivered
to the Administrative Agent a fee letter, in form and substance satisfactory to
the Administrative Agent, which fee letter shall provide for the payment by the
Borrowers to the Administrative Agent on July 15, 2012 of the first amendment
fee described in such fee letter, which first amendment fee shall be shared
ratably by those Lenders that have timely approved and executed this Amendment.
 
(c)           Other Documents:  The Administrative Agent shall have received
such other documents from the Credit Parties as the Administrative Agent shall
reasonably request in connection herewith prior to the execution of this
Amendment by the Borrowers, all of which shall be satisfactory in form and
substance to the Administrative Agent.
 
5. Miscellaneous.
 
(a) The Borrowers, the Lenders and the Administrative Agent hereby ratify and
confirm the terms and provisions of the Credit Agreement and the other Financing
Documents and agree that, except to the extent specifically amended hereby, the
Credit Agreement, the other Financing Documents and all related documents shall
remain in full force and effect.  Nothing contained herein shall constitute a
waiver of any provision of the Financing Documents.
 
(b) The Borrowers agree to pay all reasonable and documented expenses, including
legal fees and disbursements, incurred by the Administrative Agent in connection
with this Amendment and the transactions contemplated thereby.
 
(c) The Borrowers agree to provide the Administrative Agent with such updates,
reports and certifications as the Administrative Agent may from time to time
reasonably request regarding (i) the Borrowers’ compliance with and satisfaction
of all milestones and conditions required to be complied with or satisfied by
the Borrowers under the definitive binding documentation relating to the ACP
Grant (the “ACP Grant Milestones and Conditions”) and (ii) the status of all
requisite governmental approvals necessary for the funding by the DOE or any
other Governmental Authority of ACP Grant Proceeds.  The Borrowers agree to
immediately notify the Administrative Agent if (A) the Borrowers fail to comply
with or satisfy any ACP Grant Milestones and Conditions, (B) the DOE notifies
the Borrowers that they have failed to comply with or satisfy any ACP Grant
Milestones and Conditions, (C) the DOE notifies the Borrowers that they are in
default of any of their obligations under the definitive binding documentation
relating to the ACP Grant, or (D) the Borrowers become aware that the DOE or any
other Governmental Authority has made a determination to terminate or delay the
funding of any ACP Grant Proceeds.
 
(d) This Amendment may be executed in any number of counterparts (including by
way of facsimile transmission), each of which, when executed and delivered,
shall be an original, but all counterparts shall together constitute one
instrument.
 
(e) This Amendment shall be governed by the laws of the State of New York and
shall be binding upon and inure to the benefit of the parties hereto and their
respective successors and assigns.
 
[The remainder of this page is intentionally left blank; signature pages
follow.]
 

 

 
 

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly
executed by their respective authorized officers as of the day and year first
above written.
 
BORROWERS:
 
USEC INC.
 
By: /s/ Stephen S.
Greene                                                                                
 
Name: Stephen S. Greene
 
Title:   Vice President and Treasurer
 
UNITED STATES ENRICHMENT CORPORATION
 
By: /s/ Stephen S.
Greene                                                                                
 
Name: Stephen S. Greene
 
Title:  Vice President and Treasurer
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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ADMINISTRATIVE AGENT:
 
JPMORGAN CHASE BANK, N.A., as Administrative and Collateral Agent
 
By: /s/ Dan
Bueno                                                                                
 
Name: Dan Bueno
 
Title:  Vice President
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
JPMORGAN CHASE BANK, N.A., as Revolving Lender
 
By: /s/ Dan
Bueno                                                                                           
 
Name: Dan Bueno
 
Title:  Vice President
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
WELLS FARGO CAPITAL FINANCE, LLC, as Revolving Lender
 
By: /s/ Grant
Murdock                                                                                           
 
Name: Grant Murdock
 
Title:  Authorized Signatory
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
ALLY COMMERCIAL FINANCE LLC, as Revolving Lender
 
By: /s/ W. Wakefield
Smith                                                                                
 
Name: W. Wakefield Smith
 
Title: Senior Director
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
FIRST NIAGARA FINANCE, INC. a wholly-owned subsidiary of First Niagara Bank,
N.A., as Revolving Lender
 
By: /s/ Michael
Schwartz                                                                                
 
Name:  Michael Schwartz
 
Title:  Vice President
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
JPMORGAN CHASE BANK, N.A., as Term Lender
 
By: /s/ Dan
Bueno                                                                                
 
Name:  Dan Bueno
 
Title:  Vice President
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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 LENDERS:
 
HIGHBRIDGE SENIOR LOAN HOLDINGS, L.P., as Term Lender
 
By:  Highbridge Principal Strategies, LLC, its Investment Manager
 
By: /s/ Kevin
Griffin                                                                                
 
Name:  Kevin Griffin
 
Title:  Managing Director
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
HIGHBRIDGE PRINCIPAL STRATEGIES-SENIOR LOAN FUND II, L.P., as Term Lender
 
By:  Highbridge Principal Strategies, LLC, its Investment Manager
 
By: /s/ Kevin
Griffin                                                                                
 
Name:  Kevin Griffin
 
Title:  Managing Director
 

 

 

 

 
 
 

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LENDERS:
 
HIGHBRIDGE SENIOR LOAN SECTOR A INVESTMENT FUND, L.P., as Term Lender
 
By:  Highbridge Principal Strategies, LLC, its Investment Manager
 
By: /s/ Kevin
Griffin                                                                                
 
Name:  Kevin Griffin
 
Title:  Managing Director
 

 

 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
CONTINENTAL CASUALTY COMPANY, as Term Lender
 
By: /s/ Edward J.
Lavin                                                                                
 
Name:  Edward J. Lavin
 
Title:  Vice President
 
 
 
 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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LENDERS:
 
UNITED INSURANCE COMPANY OF AMERICA, as Term Lender
 
By: /s/ John
Boschelli                                                                                
 
Name:  John Boschelli
 
Title:  Assistant Treasurer
 

 

[Signature Pages to First Amendment to Fourth Amended and Restated Credit
Agreement]

 
 

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RATIFICATION OF GUARANTEE
 
The undersigned Guarantor hereby acknowledges and consents to the foregoing
First Amendment to Fourth Amended and Restated Credit Agreement (the “First
Amendment”) among USEC Inc. (“Holdings”), United States Enrichment Corporation
(together with Holdings, the “Borrowers”), those Lenders party thereto, and
JPMorgan Chase Bank, N.A., as administrative agent and collateral agent (the
“Administrative Agent”), confirms that the obligations of the Borrowers under
the Credit Agreement (as such term is defined in the First Amendment) constitute
“Guaranteed Obligations” guarantied by and entitled to the benefits of the
Fourth Amended and Restated Guarantee dated as of March 13, 2012 executed and
delivered by the Guarantor (the “Guarantee”), agrees that the Guarantee remains
in full force and effect and ratifies and confirms all of its obligations
thereunder.  Capitalized terms used but not otherwise defined herein shall have
the meanings attributed to them in the Guarantee.
 
GUARANTOR:
 
NAC INTERNATIONAL INC.
 
By: /s/ Kent S. Cole                                                         
Name:  Kent S. Cole
Title: President