**STOCK
      OPTION AGREEMENT**




THIS
      STOCK OPTION AGREEMENT (the “Agreement”) made and entered into as of August 8,
      2007 by and between KENNETH C. RICCI (“Stockholder”) and MACQUARIE
      INFRASTRUCTURE COMPANY, LLC, a Delaware limited liability company (“Macquarie”),
      is to evidence the following agreements and understandings.





**WITNESSETH** **:**





WHEREAS,
      prior to the execution and delivery of this Agreement, Stockholder owned
      7,745.36 common shares of Mercury Air Centers, Inc., a Delaware corporation
      (“MAC”), representing approximately 11% of the issued and outstanding shares of
      MAC common stock (“MAC Common”);





WHEREAS,
      Stockholder entered into an agreement with MAC dated the date hereof whereby
      each share of MAC Common held by Stockholder on such date (“Ricci Common Stock”)
      was exchanged for one (1) share of MAC Series A Preferred Stock (the “Preferred
      Stock,” the terms, preferences and rights of which are described in a
      Certificate of Designation of, Preferences and Rights of the Series A Preferred
      Stock filed with the Delaware Secretary of State (the “Certificate of
      Designations”) in connection with the terms of a Stock Purchase Agreement dated
      April 16, 2007 (the “Purchase Agreement”) by and among, *inter
      alia* ,
      Macquarie, Allied Capital Corporation (“Allied”) and Stockholder;





WHEREAS,
      the exchange of the Ricci Common Stock for the Preferred Stock was intended
      to
      qualify as a tax-free exchange under Section 1036 or as a recapitalization
      under
      Section 368(a)(1)(E) of the Internal Revenue Code of 1986, as amended, and
      the
      Preferred Stock was intended to qualify as MAC “common stock” for purposes of
      Section 305(b)(3) and the regulations promulgated thereunder;





WHEREAS,
      the Purchase Agreement provides, in part, that the Preferred Stock was to be
      issued to Stockholder in exchange for the Ricci Common Stock on the date on
      which Macquarie acquires all of the MAC Common held by Allied pursuant to the
      Purchase Agreement (the “Closing Date”), and the Purchase Agreement contemplates
      that on the Closing Date, Stockholder shall issue to Macquarie an option to
      purchase all, and not less than all, of the Preferred Stock held by Stockholder,
      and Macquarie shall issue to Stockholder an option to require Macquarie to
      purchase all, and not less than all, of the Preferred Stock held by Stockholder;





WHEREAS,
      immediately prior to the execution and delivery of this Agreement: (i) Macquarie
      has acquired all of the “Initial Closing Shares” as defined in the Purchase
      Agreement, and (ii) Stockholder has exchanged the Ricci Common Stock for an
      equal number of shares of the Preferred Stock (the “Option Shares”);
      and





WHEREAS,
      the parties hereto desire to memorialize in this Agreement the terms and
      conditions of the Call Option and the Put Option (as such terms are defined
      below).









NOW,
      THEREFORE, in consideration of the mutual promises contained herein and for
      other good and valuable consideration, the receipt, adequacy and sufficiency
      of
      which are hereby acknowledged, the parties agree as follows:





1.  Grant
      of Call Option .
      Stockholder hereby issues and sells to Macquarie an option to purchase all,
      and
      not less than all, of the Option Shares (“Call Option”), all on the terms and
      conditions contained in this Agreement.





2.  Option
      Purchase Price .
      In
      consideration of the Stockholder’s issuance of the Call Option, Macquarie shall
      pay to the Stockholder, contemporaneously with the execution and delivery of
      this Agreement, the sum of $2,000,000 (“Option Purchase Price”), by bank or
      certified check or by wire transfer of immediately available federal funds
      to an
      account designated in writing by Stockholder prior to the date of execution
      of
      this Agreement. The Option Purchase Price shall be nonrefundable, but shall
      be
      credited against the Call Option Exercise Price (defined below) if the Call
      Option is exercised by Macquarie prior to the expiration of the Call Option
      Exercise Period (defined below).





3.  Exercise
      Period .
      The
      Call Option shall be exercisable only from 12:01 a.m. Eastern Standard Time
      October 1, 2007 through 11:59 p.m. Eastern Standard Time on October 31, 2007
      (“Call Option Exercise Period”), time being of the essence.





4.  Call
      Option Exercise Price .





a.  The
      exercise price for the Option Shares acquired pursuant to the Call Option (“Call
      Option Exercise Price”) shall be $[___], the net amount of the per share value
      of the MAC Common as determined on the date hereof in connection with the
      closing of the purchase by Macquarie of MAC Common pursuant to Section 1.4(a)
      of
      the Purchase Agreement, times the number of Option Shares, plus $500,000 as
      the
      premium for Stockholder granting the Call Option, less the sum of (x) any
      dividends and distributions paid on the Preferred Stock to the Stockholder
      from
      and after the date hereof to the date of closing of the Call Option exercise
      and
      (y) the Option Purchase Price, subject to adjustment pursuant to Paragraph
      4(b)
      below.





b.  The
      parties acknowledge and agree that in certain circumstances the Call Option
      Exercise Price shall be (1) reduced by the per share amount of any Final
      Working Capital Deficiency, if any, or (2) increased by the per share
      amount of any Final Working Capital Surplus, if any, in each case pursuant
      to
      the terms and conditions set forth in Section 1.7 of the Purchase
      Agreement.





5.  Exercise
      Procedure and Closing .
      The
      Call Option may be exercised by Macquarie by delivery to Stockholder and Allied
      of a written exercise notice (“Notice of Call Exercise”) during the Call Option
      Exercise Period. Macquarie and the Stockholder shall consummate the purchase
      and
      sale of the Option Shares within ten (10) days following the date the Notice
      of
      Call Exercise is received by Stockholder.





a.  At
      the
      closing, the Call Option Exercise Price shall be paid as follows:





i.  First,
      an
      amount equal to the outstanding principal, accrued and unpaid interest, and
      fees
      payable pursuant to the Promissory Note dated September 15, 2006 and issued
      by
      the Stockholder to Mercury Air Centers, Inc. in a principal amount of $7,196,493
      (the “Allied Loan Amount”) shall be delivered to Allied Capital Corporation, a
      Maryland corporation, as agent for the holders of such note
      (“Allied”);




2




ii.  Second,
      an amount equal to the Call Option Share Escrow Fund shall be delivered to
      the
      Escrow Agent; and





iii.  Third,
      the balance of the Call Option Exercise Price for the Preferred Stock shall
      be
      delivered to the Stockholder, with payment being made in the same manner as
      the
      Option Purchase Price pursuant to Paragraph 2 above.





b.  At
      the
      closing, the Stockholder shall deliver to Macquarie:





i.  Certificates
      for the Option Shares free and clear of all liens and encumbrances (except
      with
      respect to the liens described in Paragraphs 6(a) and 12 below), duly endorsed
      for transfer or accompanied by duly executed stock powers;





ii.  A
      certificate from the Stockholder expressly certifying that as of the date
      thereof, the Stockholder (A) holds of record, owns beneficially and has good
      and
      marketable title to all of the Option Shares, free and clear of security
      interests, liens, options, warrants, purchase rights, contracts, commitments,
      restrictions, equities, claims and demands (except with respect to the liens
      described in Paragraphs 6(a) and 12 below) and (B) is not a party to any voting
      trust, proxy, or other agreement or understanding, other than with respect
      to
      this Agreement; and





iii.  An
      executed release substantially in the form of Exhibit A.





6.  Nontransferability
      of Option Shares and Call Option .





a.  Without
      the prior written consent of Macquarie and Allied, the Option Shares shall
      not
      be transferred, assigned, pledged, hypothecated or disposed of in any way
      (except with respect to the pledge described in Paragraph 12 below), whether
      by
      operation of law or otherwise, except as set forth in Paragraph 13(i) below;
      provided, that the Option Shares may be disposed of pursuant to the
      Agreement.





b.  Without
      the prior written consent of the Stockholder, the Call Option shall not be
      transferred, assigned, pledged, hypothecated or disposed of in any way, whether
      by operation of law or otherwise, except that Macquarie, upon written notice
      to
      the Stockholder, may (i) transfer all or a portion of the Call Option to an
      affiliate to whom the Option Shares may be immediately transferred in compliance
      with Section 4.02 of the Share Pledge Agreement dated the date hereof by and
      between Stockholder and The Bank of New York, as collateral agent (“BONY
      Pledge”), and Macquarie shall cause such assignee to continue to qualify to
      receive the Option Shares in compliance with Section 4.02 of the BONY Pledge
      until the Option Shares have been transferred pursuant to the Put Option or
      Call
      Option and the consideration for the Option Shares paid or (ii) grant a security
      interest in the Call Option to secure the repayment of indebtedness of MAC,
      in
      each such case Macquarie shall remain primarily liable for and stand behind
      each
      of its obligations under the Call Option and otherwise under this Agreement;
      provided, that following the termination of the restrictions in the BONY Pledge
      regarding transferees of the Option Shares, Macquarie, upon written notice
      to
      the Stockholder, may transfer all or a portion of the Call Option to an
      affiliate, in which case Macquarie shall remain primarily liable for and stand
      behind each of its obligations under the Call Option and otherwise under this
      Agreement.




3




7.  Failure
      to Exercise Call Option / Stockholder’s Right to Appointment of
      Director .
      If
      Macquarie fails to exercise the Call Option prior to the expiration of the
      Call
      Option Exercise Period or fails to close on the purchase of the Preferred Stock
      within ten (10) days after receipt by Stockholder of the Notice of Exercise,
      the
      Stockholder shall be permitted to appoint an additional director to the Board
      of
      MAC (which Board will consist of at least six (6) members) as long as the
      Stockholder (or family members, including trusts, limited partnerships or
      limited liability companies principally for the benefit of Stockholder or his
      family (“Stockholder Related Parties”)) continues to own in the aggregate at
      least eighty percent (80%) of the Preferred Stock. Macquarie agrees to vote
      for
      the election of Stockholder’s nominee as Director and take such actions in its
      capacity as majority stockholder of MAC, and further, agrees to cause MAC to
      take such actions as may be necessary or appropriate, in the reasonable opinion
      of Stockholder or its counsel, to effectuate the purposes of this
      Paragraph.





8.  Stockholder
      Failure to Transfer Preferred Stock .
      In the
      event that the Stockholder is unable to, or for any reason does not, deliver
      to
      Macquarie certificates for the Preferred Stock free and clear of all liens
      and
      encumbrances (except with respect to the liens described in Paragraphs 6(a)_and
      12 below), duly endorsed for transfer or accompanied by duly executed stock
      powers and an executed release substantially in the form of Exhibit A within
      ten
      (10) days after receipt by Stockholder of the Notice of Exercise, Macquarie
      may,
      in its sole discretion, pay to Allied the amount payable to it pursuant to
      Paragraph 5 above and deposit the balance of the Call Option Exercise Price
      to
      the Escrow Agent to be held in an escrow account separate from the Escrow Fund.
      Upon such deposit by Macquarie, the Option Shares shall at such time be deemed
      to have been sold, assigned, transferred and conveyed to Macquarie, and the
      Stockholder shall have no further rights with respect thereto. The Escrow Agent
      shall hold, invest and disburse the funds in accordance with the terms and
      conditions of an escrow agreement between Macquarie, the Stockholder and the
      Escrow Agent, an executed counterpart of which the Stockholder has delivered
      to
      Macquarie as of the execution of this Agreement. The escrow agreement shall
      provide that the escrow deposit and any investment income earned thereon be
      disbursed in accordance with the sequence set forth in Paragraphs 5(a)(ii)
      and
      (iii) above upon receipt by Macquarie of the documents set forth in the first
      sentence of this Paragraph 8. Any fees and expenses of the Escrow Agent shall
      be
      paid from the funds deposited with the Escrow Agent.





9.  Adjustments
      for Certain Corporate Events .
      If at
      any time, or from time to time, MAC shall, by subdivision, consolidation or
      reclassification of shares, or otherwise, change as a whole the outstanding
      Option Shares into a different number or class of shares, the number and class
      (or series) of shares so changed shall, for the purposes of the Call Option
      or
      the Put Option (as defined below) and the terms and conditions hereof, replace
      the shares outstanding immediately prior to such change, and the number of
      shares subject to the Call Option or the Put Option and the consideration
      calculated based on the number of Option Shares shall be proportionately
      adjusted.




4




a.  If
      at any
      time, or from time to time while the Call Option or Put Option is exercisable,
      MAC shall consolidate with or merge into another corporation, Macquarie shall
      thereafter be entitled upon exercise of the Call Option to purchase, with
      respect to each Option Share purchasable hereunder immediately prior to the
      date
      upon when such consolidation or merger shall become effective, the securities
      or
      property to which a holder of one share of Preferred Stock would have been
      entitled upon such consolidation or merger and Macquarie shall take, and shall
      cause MAC to take such steps in connection with such consolidation or merger
      as
      may be necessary to assure that all of the provisions of the Call Option or
      the
      Put Option shall thereafter be applicable, as nearly as reasonably may be,
      in
      relation to any securities or property thereafter deliverable upon the exercise
      of the Call Option or the Put Option as applicable.





b.  The
      Call
      Option granted herein shall not entitle Macquarie to any voting rights or other
      rights or privileges attributable to ownership of the Option Shares prior to
      the
      exercise of the Call Option or the Put Option, as applicable, and payment of
      the
      exercise price for such shares.





10.  Put
      Option Exercise Price .





a.  The
      Stockholder shall have the option to require Macquarie to purchase all, and
      not
      less than all, of the Preferred Stock held by the Stockholder (“Put Option”),
      exercisable only from 12:01 a.m. Eastern Standard Time April 1, 2008 through
      11:59 p.m. Eastern Standard Time April 30, 2008 (“Put Option Exercise Period”),
      time being of the essence. The exercise price for the Option Shares being sold
      to Macquarie pursuant to the Put Option (“Put Option Exercise Price”) shall be
      $[___], the net amount of the per share value of MAC Common as determined on
      the
      date hereof in connection with the closing of the purchase by Macquarie of
      the
      MAC Common pursuant to Section 1.4(a) of the Purchase Agreement times the number
      of Option Shares, less the sum of (x) $4,000,000 and (y) any dividends and
      distributions paid to Stockholder on the Preferred Stock from and after the
      date
      hereof through the date of closing of the Put Option exercise, and without
      reduction for the Option Purchase Price, subject to adjustment pursuant to
      Paragraph 10(b) below.





b.  The
      parties acknowledge and agree that in certain circumstances the Put Option
      Exercise Price shall be (1) reduced by the per share amount of any Final
      Working Capital Deficiency, if any, or (2) increased by the per share
      amount of any Final Working Capital Surplus, if any, in each case pursuant
      to
      the terms and conditions set forth in Section 1.7 of the Purchase
      Agreement.





11.  Exercise
      Procedure and Closing .
      The Put
      Option may be exercised by Stockholder by delivery to Macquarie and Allied
      of a
      written exercise notice (“Notice of Put Exercise”) during the Put Option
      Exercise Period. Stockholder and Macquarie shall consummate the sale of the
      Preferred Stock within ten (10) days of the date of receipt by Macquarie of
      the
      Notice of Put Exercise.




5




a.  At
      the
      closing, the Put Option Exercise Price shall be paid as follows:





i.  First,
      an
      amount equal to the Allied Loan Amount shall be delivered to
      Allied;





ii.  Second,
      an amount equal to the Option Share Escrow Fund shall be delivered to the Escrow
      Agent;





iii.  Third,
      the balance of the Put Option Exercise Price for the Preferred Stock shall
      be
      delivered to the Stockholder, with payment being made in the same manner as
      the
      Option Purchase Price pursuant to Paragraph 2 above.





b.  At
      the
      closing, the Stockholder shall deliver to Macquarie:





i.  Certificates
      for the Option Shares free and clear of all liens and encumbrances (except
      with
      respect to the liens described in Paragraphs 6(a) and 12 below), duly endorsed
      for transfer or accompanied by duly executed stock powers;





ii.  A
      certificate from the Stockholder expressly certifying that as of the date
      thereof, the Stockholder (A) holds of record, owns beneficially and has good
      and
      marketable title to all of the Option Shares, free and clear of security
      interests, liens, options, warrants, purchase rights, contracts, commitments,
      restrictions, equities, claims and demands (except with respect to the liens
      described in Paragraphs 6(a) and 12 below) and (B) is not a party to any voting
      trust, proxy, or other agreement or understanding, other than with respect
      to
      this Agreement;





iii.  And
      an
      executed release substantially in the form of Exhibit A.





12.  Support
      of Financing Transaction .
      Upon
      request by Macquarie, the Stockholder will enter into a stock pledge agreement
      containing customary terms and conditions and on terms no less favorable than
      applicable to Macquarie, if required by any bank or other financial institution
      providing bona fide financing to MAC for the purpose of making distributions
      to
      all shareholders, including the holder of the Preferred Stock and refinancings
      of such debt that do not increase the principal amount thereof. Any such stock
      pledge agreement shall expressly provide that the transfer of the Preferred
      Stock to either Macquarie or MAC or their respective affiliates is a permitted
      transfer under the express terms of the stock pledge agreement. Macquarie
      acknowledges and agrees that: (i) any grant of a security interest in the Option
      Shares contemplated by this Paragraph 12 is a permitted lien on the Preferred
      Stock for purposes of closing on the sale of the Preferred Shares to either
      Macquarie or MAC and shall not result in a reduction to the net amount paid
      to
      Stockholder from the sale of the Preferred Stock; and (ii) in the event of
      a
      default by MAC under any bank loan contemplated by this Paragraph for which
      Stockholder has pledged his Preferred Stock as security for payment, Macquarie
      will indemnify and hold harmless Stockholder from and against any Losses
      incurred by Stockholder in respect of such loan (including, but not limited
      to,
      foreclosure against the pledged shares) to the extent such Losses incurred
      by
      Stockholder exceeds the amount of distributions received by Stockholder after
      the closing, such indemnity obligation not to exceed the aggregate amount of
      proceeds the Stockholder is otherwise entitled to receive under this Agreement
      and the Purchase Agreement.




6




13.  Miscellaneous
      Provisions .





a.  Governing
      Law / Jurisdiction and Venue .
      This
      Agreement shall be governed by and construed in accordance with the laws of
      the
      State of Delaware. Jurisdiction and venue for any action or claim arising
      hereunder shall lie exclusively in the Court of Chancery in the State of
      Delaware, and each party irrevocably consents and submits to the personal and
      subject matter jurisdiction of said courts.





b.  Headings .
      Section
      and paragraph headings are not to be considered part of this Agreement. They
      are
      included solely for convenience and are not intended to be full and accurate
      descriptions of the contents of this Agreement.





c.  Recitals
      and Exhibits .
      The
      recitals set forth at the beginning of this Agreement and the Exhibits annexed
      hereto are an integral part of this Agreement and are incorporated herein by
      reference as if fully rewritten.





d.  No
      Waiver .
      A
      waiver of any provisions of this Agreement shall not be effective unless in
      writing signed by the party against whom the waiver is claimed. No waiver of
      any
      provision of this Agreement shall constitute a waiver of any other provision,
      whether or not similar, and no waiver shall constitute a continuing waiver
      unless expressly provided in writing.





e.  Execution
      in Counterparts .
      This
      Agreement may be executed by facsimile or other electronic communication in
      multiple counterparts, each of which shall constitute an original for all
      purposes, but all of which constitute but one and the same
      instrument.





f.  Notices .
      Any
      notice or other communication with respect to this Agreement to any party shall
      be in writing and shall be deemed to have been delivered when personally
      delivered, one business day after being sent via a reputable nationwide
      overnight courier service guaranteeing next Business Day delivery charges
      prepaid or three days after being deposited in the United States mail, certified
      and postage prepaid, addressed to the appropriate party as follows:




To the Stockholder:
            Kenneth C. Ricci355 Richmond RoadRichmond Heights, Ohio 44143To Macquarie:
            Macquarie Infrastructure Company,
              LLC125 West 55thStreetNew York, New York 10019Attn: Peter
              Stokes.




7




A copy of notices shall be sent to:
            Allied Capital Corporation1919 Pennsylvania Ave., N.W.,Washington, DC 2006Attn: Mark
              Raterman.





Any
      addressee may designate a different address by delivering, as provided above,
      a
      notice of change of address.





g.  Modification .
      This
      Agreement may be modified only in a writing executed by all parties and with
      the
      consent of Allied which will not be unreasonably withheld, conditioned or
      delayed.





h.  Binding
      Effect .
      This
      Agreement shall bind and inure to the benefit of the parties hereto and their
      respective heirs, legal representatives, successors and permitted
      assigns.





i.  Limited
      Assignment .
      The
      rights and obligations of Macquarie under this Agreement may not be assigned,
      nor its obligations hereunder be assumed, in whole or in part, to or by any
      person or entity which is not a party to this Agreement without the prior
      written consent of the Stockholder, except as expressly provided pursuant to
      Section 6. The rights and obligations of the Stockholder under this Agreement
      may not be assigned, nor its obligations hereunder be assumed, in whole or
      in
      part, to or by any person or entity which is not a party to
      this
      Agreement without the prior written consent of Macquarie; provided that (a)
      pursuant to a Pledge and Collateral Assignment Agreement dated April 16, 2007
      (“Pledge Agreement”), as it may be amended from time to time, the Stockholder
      may and has pledged and assigned its right, title and interest in the Agreement
      to, granted a proxy and power of attorney to, and granted a security interest
      in
      and assigned certain proceeds to Allied, and Macquarie acknowledges the Pledge
      Agreement and agrees that Allied may serve as agent for the holders of the
      “Note” as defined in the Pledge Agreement and
      (b)
      following the expiration of the Call Option Exercise Period, Stockholder, upon
      written notice to Macquarie may assign all or a portion of the Put Option to
      one
      or more Stockholder Parties, and in each such case (a) and (b) Stockholder
      shall
      remain primarily liable for and stand behind each of his obligations under
      this
      Agreement.





j.  Entire
      Agreement .
      This
      Agreement, together with the Purchase Agreement, the Escrow Agreement and the
      other Transaction Documents, constitutes the entire understanding among the
      parties and supersedes any prior understandings and agreements between them
      respecting the within subject matter. There are no representations, agreements,
      arrangements or understandings, oral or written, between or among the parties
      with respect to the within subject matter, other than as set forth in this
      Agreement and its Exhibits. In the event of any conflict between the terms
      of
      this Agreement and the Purchase Agreement, the Purchase Agreement shall
      govern.





k.  Further
      Assurances .
      From
      and after the closing, each party shall execute and deliver such further
      instruments of conveyance and transfer and take such other action as reasonably
      may be requested by the other party to further effectuate the transactions
      contemplated by this Agreement.




8




l.  Confidentiality .
      The
      parties covenant and agree that the terms and conditions of this Agreement
      shall
      not be disclosed or disseminated in any fashion, at any time, or for any person,
      firm or entity except for the parties’ respective accountants, attorneys and
      financial advisors and except as may be required by law; provided, that the
      Stockholder hereby consents to the disclosure by Macquarie and its Affiliates
      of
      information regarding the Company, the Subsidiaries and the Business, to the
      extent contemplated by Section
      5.3(b) of the Purchase Agreement ,
      or as
      reasonably necessary for compliance with disclosure requirements applicable
      to
      Macquarie or any of its Affiliates, provided such disclosure is made in
      accordance with and pursuant to Legal Requirements (including applicable federal
      securities laws and stock exchange listing rules).





m.  Specific
      Performance .
      The
      Stockholder and Macquarie agree that irreparable damage would occur in the
      event
      that any provision of this Agreement was not performed in accordance with the
      terms hereof and that the Stockholder and Macquarie shall be entitled to
      specific performance of the terms hereof, in addition to any other remedy at
      law
      or in equity.





n.  Defined
      Terms .
      Capitalized terms not defined in this agreement shall have the meaning given
      in
      the Purchase Agreement.




9




IN
      WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
      date
      first above written.





/s/
              Kenneth C.
              RicciKENNETH
              C. RICCI




MACQUARIE
              INFRASTRUCTURE COMPANY, LLCBy:
            /s/
              Peter StokesPeter
              Stokes, its
              _____________________




10


Exhibit
      A





Form
      of
      Release of Claims





As
      of the
      closing of the sale of the “Option Shares”, as defined in the Stock Option
      Agreement dated as of __________, 2007 (the “Option Agreement”) by and between
      Kenneth C. Ricci (“Seller”) and Macquarie Infrastructure Company, LLC (the
“Company”), Seller hereby fully and irrevocably releases, acquits and forever
      discharges the Company and the Subsidiaries, and each of their respective past,
      present and future officers, directors, partners, general partners, limited
      partners, managing directors, members, stockholders, trustees, representatives,
      employees, principals, agents, Affiliates, parents, subsidiaries (direct and
      indirect), joint ventures, predecessors, successors, assigns, beneficiaries,
      heirs, executors, personal or legal representatives, insurers and attorneys
      of
      any of them from any and all actions, claims, counterclaims, suits, causes
      of
      action, judgments, damages, demands and liabilities, of every kind and nature
      whatsoever, including taxes (including taxes under Sections 409A and 4999 of
      the
      Code), past, present or future, at law or in equity, whether known or unknown,
      contingent or otherwise, relating to or arising out of the ownership or
      acquisition of the Option Shares or the business and affairs of the Company
      and
      the Subsidiaries, in each case, which such Seller had, has or may have had
      at
      any time in the past until and including the date of the closing of the sale
      of
      the Option Shares, including any claims regarding the allocation and
      distribution of the Purchase Price (collectively, “Released Claims ” ).
      Notwithstanding the foregoing, the Released Claims shall not include
      (i) exculpation and indemnification rights set forth in the Company’s or
      any Subsidiary’s charter documents or any written indemnification agreement, to
      the extent described on the attached D&O
      Indemnification Schedule to the
      Purchase Agreement (as defined below), (ii) any amounts due Seller for
      compensation or expense reimbursement, (iii) any vested and accrued interest
      of
      Seller in, or benefit to such Seller under, any Employee Benefit Plan, (iv)
      rights arising under any Transaction Document, other than any claims regarding
      the allocation and distribution of the Purchase Price, or (v) rights under
      directors and officers insurance policies and Section
      5.10 of the
      Purchase Agreement. The releases, acquittals and discharges in this Release
      of
      Claims are conditioned on the consummation of the closing of the sale of the
      Option Shares. Capitalized terms not defined in this agreement shall have the
      meaning given in the Option Agreement or the “Purchase Agreement,” as Purchase
      Agreement is defined in the Option Agreement.




Kenneth
              C. RicciDate:
              ___________









**ASSIGNMENT
      AGREEMENT**





This
      Assignment Agreement (this “Agreement”) is entered into as of the 8th day of
      August, 2007 by and between Macquarie Infrastructure Company, LLC, a Delaware
      limited liability company (“Assignor”) and Macquarie FBO Holdings LLC, a
      Delaware limited liability company and direct subsidiary of Assignor
      (“Assignee”). Capitalized terms used herein without definitions shall have the
      meanings ascribed to them in that certain Stock Option Agreement by and among
      Kenneth C. Ricci (the “Stockholder”) and Assignor, dated as of August 8, 2007, a
      copy of which is attached hereto (the “Option Agreement”).





**WHEREAS** ,
      Assignor is a party to the Option Agreement;





**WHEREAS** ,
      Section
      6(b) of the Option Agreement expressly authorizes Assignor to assign the Call
      Option under the Option Agreement to an affiliate without the prior consent
      of
      the Stockholder, in which case Assignor shall remain primarily liable for and
      stand behind each of its obligations under the Call Option and otherwise in
      the
      Agreement;





**WHEREAS** ,
      Assignor desires to assign to Assignee all of Assignor’s right to the Call
      Option under the Option Agreement;





**WHEREAS** ,
      Assignee has agreed to assume Assignor’s right to the Call Option;
      and





**WHEREAS** ,
      Assignor has agreed to remain primarily liable for and stand behind each of
      its
      obligations under the Call Option and all other obligations and liabilities
      in,
      to and under the Option Agreement.





**NOW
      THEREFORE** ,
      in
      consideration of the foregoing premises, and for good and valuable
      consideration, the receipt and sufficiency of which are hereby acknowledged,
      Assignor and Assignee agree as follows:





1.  Assignment
      of Right to the Call Option .
      Assignor hereby assigns all of its right to the Call Option under the Option
      Agreement to Assignee, free and clear of any liens or encumbrances arising
      by,
      through or under Assignor, but otherwise without recourse, representation or
      warranty (express or implied) of any kind.





2.  Liability
      of Assignor .
      Assignor acknowledges that it shall remain primarily liable for and stand behind
      each of its obligations under the Call Option and all other obligations and
      liabilities in, to and under the Option Agreement. Such assignment and
      assumption is without recourse, representation or warranty (express or implied)
      of any kind.





3.  Certain
      Covenants and Agreements .
      Assignor covenants and agrees to make, execute and deliver any and all
      additional acts or documents as Assignee shall from time to time reasonably
      request to better assure, convey, assign and transfer or to otherwise vest
      in
      Assignee all right, title and interest of Assignor to the Call
      Option under the Option Agreement .
      Each of
      Assignor and Assignee covenants and agrees that it will not take, or fail to
      take, any action pursuant to the Option
      Agreement that
      could reasonably be expected to adversely affect the other party’s rights
      hereunder or thereunder.









4.  Miscellaneous .





(a)  This
      Agreement evidences the complete understanding and agreement of the parties
      with
      respect to the subject matter hereof. This Agreement may not be modified except
      by a writing subscribed to by authorized representatives of each
      party.





(b)  This
      Agreement shall be governed by the laws of the State of New York, without giving
      effect to its conflict of laws principles.





(c)  This
      Agreement shall apply to, inure to the benefit of, and be binding upon the
      parties hereto and upon their successors in interest and assigns.





(d)  This
      Agreement may be executed in counterparts, each of which shall be deemed an
      original, but together shall constitute one and the same document. Once signed,
      any reproduction of this Agreement made by reliable means (including photocopy
      or facsimile) shall be considered an original.





[ ***Signature
      Page Follows*** ]


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IN
      WITNESS WHEREOF, the parties hereto have executed and delivered this Assignment
      Agreement as of the date first written above.




**ASSIGNOR**Macquarie Infrastructure Company, LLC,
              a Delaware limited liability company/s/
              Peter
              StokesPeter
              StokesIts: Chief Executive
              Officer




**ASSIGNEE**Macquarie FBO Holdings LLC,
              a Delaware limited liability companyMacquarie Infrastructure Company Inc.,
              its managing member/s/
              Peter
              StokesPeter Stokes
              Chief Executive
                Officer




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