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August 2, 2004

Ms. Pamela D.A. Reeve
35 Swan Road
Winchester, MA 01890

RE:  SEPARATION AGREEMENT AND RELEASE

Dear Pam:

      This letter agreement will confirm our mutual understanding with respect
to the arrangements we have made in connection with the termination of your
position as an officer of Lightbridge, Inc. ("Lightbridge" or the "Company") and
the termination of your employment.

      1.    RESIGNATION AS OFFICER; TERMINATION OF EMPLOYMENT.

      You hereby confirm your resignation as an officer of the Company effective
August 2, 2004. Your status as an employee and all employee benefits will
terminate effective August 13, 2004 (the "Employment Termination Date") except
as otherwise provided herein.

      2.    RESIGNATION AS DIRECTOR.

      You hereby irrevocably tender your resignation from the Board, effective
August 2, 2004.

      3.    SEVERANCE PAYMENTS.

      If you sign this letter agreement and release (and do not timely revoke
your agreement as set forth in paragraph 16), then (a) you will be paid a lump
sum amount equal to twelve months of your current base salary (less required
withholdings and deductions for taxes) and (b) you will continue to receive your
current base salary (less required withholdings and deductions for taxes) on the
Company's normal payroll cycle from the date hereof until the first anniversary
of the Employment Termination Date. You agree that the payments described in
this letter agreement are above and beyond and in full satisfaction of any
payments or compensation otherwise owed to you under the terms of your
employment with Lightbridge, your employment agreement dated August 16, 1996
(the "Employment Agreement"), or as required by law.

      4.    ACCRUED PAID VACATION AND TIME OFF.

      All accrued but unused vacation time earned through the Employment
Termination Date will be paid on that date.

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      5.    VOICEMAIL, COMPUTER, AND RETURN OF COMPANY PROPERTY.

      Use of voicemail will be provided through October 31, 2004, and network
access will also be provided through the Employment Termination Date. You will
return all other property, equipment and materials of the Company, other than
the Company-owned automobile, laptop computer and wireless telephone currently
used by you (the "Retained Company Property"), to the Company promptly after the
Employment Termination Date. If you do not revoke your agreement within the time
period set forth in paragraph 16, the Company will thereupon assign ownership of
the Retained Company Property to you.

      6.    COBRA GROUP INSURANCE COVERAGE.

      As of the Employment Termination Date, you and your family members will be
eligible to continue your group health insurance coverage in accordance with the
federal COBRA law. Should you or any of your family members elect COBRA
continuation coverage for the eighteen month period immediately following the
Employment Termination Date, the Company shall be responsible for paying the
difference between the cost of COBRA continuation coverage and the premium
contribution amount applicable to you as of the Employment Termination Date,
subject to any applicable carrier and Company rate adjustments. After such
eighteen month period ends, if you or any of your family members elect to
continue COBRA coverage, you will be responsible for all of the premium
payments. Information about your rights under COBRA and forms for electing
continuation coverage will be provided to you by a separate letter on or about
the Employment Termination Date.

      7.    OUTPLACEMENT ASSISTANCE.

      To assist you in regard to outplacement, the Company will pay up to
$50,000 for outplacement services which are provided to you by a
Company-approved agency prior to the earlier of July 31, 2005 or the date you
commence new employment. Appropriate invoices for outplacement services should
be submitted promptly to the Company.

      8.    CONFIDENTIAL INFORMATION.

      You understand and agree that the Company's confidential information
belongs exclusively to the Company, and that the confidential information of the
Company's customers or of other organizations with which the Company does
business remains their exclusive property. You agree that you will not use or
disclose any such confidential information, whether for your benefit or for the
benefit of another, and that you will hold and treat such information as
confidential information, unless you have specific prior written authorization
from the Company to disclose it. Incorporated herein is a confidentiality and
non-competition agreement that was signed by you on or about July 17, 1990 and
which remains in effect according to its terms.

      9.    NON-DISPARAGEMENT; COOPERATION.

      You agree that you will not make any disparaging statements about the
Company or any of its subsidiaries, affiliates, officers, directors or
employees, or its business or prospects. The

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Company and its executive officers and Directors agree that they will not make
any disparaging statements about you.

      Through the first anniversary of the Employment Termination Date, you
agree to provide assistance and support as requested from time to time by the
Board of Directors without additional compensation with respect to any matters
required for the orderly transition of your former employment responsibilities
or otherwise related to the business of the Company; provided, however, that you
will not be required to devote more than eight hours per month to providing such
assistance and support.

      10.   RELEASE AND WAIVER.

      This letter agreement and the agreement referenced in paragraph 8 contain
the entire agreement between you and the Company (and supersede any prior
communications, written or oral) with respect to your employment by the Company
and the termination of such employment, and with respect to all matters
pertaining thereto including, without limitation, those set forth in the
Employment Agreement. This letter agreement shall be in complete and final
settlement of any and all causes of action or claims that you have had, now have
or may now have, in any way related to or arising out of or in connection with
such employment and/or its termination or pursuant to any federal, state or
local employment laws, regulations, executive orders or other requirements,
including without limitation Massachusetts General Laws c. 151B ("Unlawful
Discrimination"), Title VII of the Civil Rights Act of 1964, and the Age
Discrimination in Employment Act of 1967. In consideration of the pay and
benefits that you will receive under this letter agreement, you hereby release,
waive and discharge any and all such causes of action or claims (including
without limitation claims for attorney's fees and costs) against the Company,
its parent, subsidiary and affiliated organizations, and their respective past,
present and future directors, officers, agents, employees, successors and
assigns, and you hereby agree that, to the extent permitted by law, neither you
nor any of your heirs or personal representatives will ever assert in any forum
any such cause of action or claim. THIS MEANS YOU MAY NOT SUE LIGHTBRIDGE FOR
ANY CURRENT OR PRIOR CLAIMS ARISING OUT OF YOUR EMPLOYMENT WITH OR TERMINATION
FROM LIGHTBRIDGE.

      You further agree that you will not bring any lawsuits, file any charges
or complaints, or make any other demands against Lightbridge, or further pursue
any lawsuits, cases or complaints already brought, based on your employment by
Lightbridge. You further represent that you have no current or pending actions,
charges, lawsuits, or complaints against Lightbridge. You acknowledge and
understand that the consideration provided for in this letter agreement
constitutes a full, fair and complete payment for the release and waiver of all
of your possible claims. You acknowledge and understand that Lightbridge does
not owe you anything for your employment in addition to the consideration set
forth in this letter agreement.

      11.   COMPLIANCE.

      All payments to be made to you in accordance with the terms of this letter
agreement, and the performance by the Company of its other obligations hereunder
shall be conditioned on your compliance with your obligations hereunder.

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      12.   GOVERNING LAW.

      The parties intend this letter agreement to be governed by the substantive
laws of The Commonwealth of Massachusetts.

      13.   CHALLENGE TO VALIDITY OF LETTER AGREEMENT.

      Lightbridge and you shall never bring a proceeding to challenge the
validity of this letter agreement. If you do, you will first be required to pay
back to Lightbridge any monies received from Lightbridge under paragraph 3 of
this letter agreement.

      14.   ENFORCEMENT.

      In the event that you violate any of the terms of paragraphs 8 or 9 of
this letter agreement or the Company determines that you have breached your
fiduciary duty to the Company, then any payments required to be made hereunder
shall cease. In the event that you violate paragraphs 8 or 9, in addition to any
money damages that Lightbridge may be owed, Lightbridge shall also be entitled
to seek and obtain an order enjoining any future violations.

      15.   CONSIDERATION PERIOD.

      In signing this letter agreement, you acknowledge that you understand its
provisions, that your agreement is knowing and voluntary, that you have been
afforded a full and reasonable opportunity of at least 21 days to consider its
terms and to consult with or seek advice from an attorney or any other person of
your choosing, and that you have been advised by the Company to consult with an
attorney prior to executing this letter agreement and the release and waiver of
claims in paragraph 10.

      16.   REVOCATION PERIOD.

      For a period of seven (7) days following your execution of this letter
agreement and release, you may revoke your agreement, and this letter agreement
and release shall not become effective or enforceable until this seven (7) day
revocation period has expired. No payments provided for by this letter agreement
will be made until after this seven-day period has expired without your revoking
your agreement. You understand and acknowledge that the terms of your employment
and the Company's usual severance policies or practices would have provided you
less severance pay and benefits than those provided to you under this letter
agreement.

      17.   STOCK OPTIONS.

      You are currently the holder of certain options to purchase shares of the
Company's common stock, $.01 par value per share. The Company agrees that,
notwithstanding the terms of the option agreements and related plans, all such
options shall be deemed to be vested in full immediately following the
expiration of the revocation period described in paragraph 16, and shall remain
exercisable in full in accordance with their terms until 18 months following the

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expiration of such revocation period. You understand that, as a result of the
foregoing agreements, your options will no longer qualify for incentive stock
option treatment under the Internal Revenue Code.

      If you agree to the foregoing, would you kindly sign and return the
enclosed copy of this letter agreement, whereupon this letter agreement and such
copy will constitute a binding agreement between you and the Company on the
basis set forth above.

Very truly yours,

LIGHTBRIDGE, INC.

By:  /s/ Eugene DiDonato                                      8/2/04
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     Eugene DiDonato                                 Date
     Vice President and General Counsel

AGREED: /s/ Pamela D.A. Reeve                                8/2/04
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        Employee's Signature                         Date signed

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