Document:

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                                                                     Exhibit 4.8

                               SECURITY AGREEMENT

     1.   Date.        January 28, 2003

     2.   Parties.     The parties to this Agreement are:

                       Debtors:                  EARTHFIRST NEXTGAS, INC.
                                                 GIBSONTON PROPERTY, INC.
                                                 EARTHFIRST RESOURCES, INC.

                       Secured Party:            FLORIDA ENGINEERED CONSTRUCTION
                                                 PRODUCTS CORPORATION

     3.   Grant of Security Interest. The Debtors hereby grant to the Secured
Party a security interest in the following Collateral to secure the payment and
performance of the obligations set out in this Agreement.

     4.   Collateral. The property serving as Collateral and subject to the
above security interest are all furniture, fixtures, equipment, accounts
receivable, all stock, including the stock of all subsidiaries, all interests in
limited liability companies and partnerships, and all other personal property
and intangible assets of the Debtors.

     5.   Obligations of Debtors. The obligations of the Debtors that are
subject to this Security Agreement are the repayment of that certain Revolving
Line of Credit Promissory Note ("Promissory Note") dated December 15, 2000, in
the principal amount of Two Million Five Hundred Thousand and 00/100 Dollars
($2,500,000.00) from EarthFirst Technologies, Inc. ("EFT") in favor of Secured
Party, for which Debtors are jointly and severally liable pursuant to the terms
of the Joinder executed on even date herewith. The terms and conditions of such
Promissory Note and Joinder are expressly incorporated herein. A copy of said
Promissory Note and Joinder are attached hereto as Composite Exhibit "A".

     6.   Warranties and Commitments. Debtors hereby warrant and agree to the
following:

          (a)  Title. The Debtors are the owners with the full right and
               interest in the Collateral that is subject to this Agreement,
               which is free and clear of any and all liens, claims,
               encumbrances, and the like, with the exception of any liens or
               encumbrances which have been disclosed to Secured Party. The
               Debtors have full authority to use the same as Collateral and
               agree to defend the Collateral against all other persons who, at
               any time, may claim an interest in it.

          (b)  Negative Pledge. The Debtors agree that during the course of this
               Agreement and as long as any obligation that is subject to this
               Agreement remains outstanding, the Debtors will not grant a
               security interest in the Collateral subject to this Agreement to
               any person or entity without the prior written consent of the
               Secured Party.

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          (c)  Liens and Encumbrances. The Debtors agree that during the course
               of this Agreement and as long as any indebtedness or other
               obligation that is subject to this Agreement remains outstanding,
               the Debtors will keep the Collateral free from any and all liens,
               encumbrances, and the like.

          (d)  Assignment of Collateral. The Debtors will not assign, transfer,
               discount, sell, offer for sale, or otherwise dispose of the
               Collateral or any interest in the Collateral save as provided in
               this Security Agreement without prior written consent of the
               Secured Party.

          (e)  Taxes. The Debtors agree to pay all taxes and assessments on the
               Collateral as required and when due. Should the Debtors fail to
               do so, the Secured Party, although not required to do so, may, at
               its sole option, pay or discharge the same. Any such payment
               shall become an obligation of the Debtors which is secured by the
               collateral to this Agreement.

          (f)  Corporate Authority. Each of Debtors, warrants that:

               (i)     It is duly authorized and existing under the laws of the
                       State of Florida.

               (ii)    It is qualified and in good standing in all states in
                       which it is doing business.

               (iii)   The execution and performance of this Agreement:

                       (1)  Are within the Debtors' corporate powers;

                       (2)  Have been duly authorized; and

                       (3)  Are not in contravention of any law or the Debtors'
                            respective charters, or any agreement or undertaking
                            of which any of the Debtors is a party or by which
                            it is bound.

         7. Financing Statements and Other Documents. The Debtors agree to
execute one or more Financing Statements as determined by Secured Party and in a
form satisfactory to the Secured Party, and Secured Party is authorized to file
Financing Statements in any location deemed necessary or advisable to perfect
the Secured Party's security interest in the Collateral or proceeds. The Debtors
expressly agree to sign such Financing Statements on request of the Secured
Party.

         The Debtors also agree to cooperate fully with the Secured Party in
executing additional instruments, documents, financing statements, amendments to
financing statements, and the like as may be deemed necessary or advisable by
the Secured Party in order to maintain and continue the security interest
created by this Security Agreement.

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     The Debtors agree that a carbon, photographic or other reproduction of a
Financing Statement is sufficient as a financing statement under this Agreement.

     8.   Reports, Inspections and the Like.

               (a)  The Debtors agree to the examination, auditing, and
                    inspection of their books and records from time to time by
                    the Secured Party, its assigns, or its agents as may be
                    deemed necessary or advisable by the Secured Party in the
                    protection of its interests under this Agreement. The
                    Debtors agree to cooperate fully in this matter and further
                    agree to the making of extracts and copies as well as to the
                    verification of all accounts by the Secured Party or its
                    agents, which includes but is not limited to the contracting
                    of account debtors.

               (b)  The Debtors will furnish on request and from time to time to
                    the Secured Party or its assigns trial balances on aged
                    accounts; statements of accounts or commissions with
                    customers or insurance carriers; and certified financial
                    statements, including but not limited to, balance sheet and
                    profit and loss statements, together with accountant's
                    comments.

               (c)  The Debtors will promptly inform the Secured Party or its
                    assigns of any change in directors, officers or key
                    employees.

               (d)  The Debtors will cooperate fully with the Secured Party or
                    its assigns in the furnishing of such assignments,
                    schedules, documents and the like as they may deem necessary
                    or advisable to the creation, perfection, maintenance or
                    protection of their interest in the Collateral subject to
                    this Agreement.

     9.   Collections.

               (a)  The Debtors shall collect the accounts and other obligations
                    serving as Collateral or proceeds under this Agreement and
                    shall do so at the Debtors' own expense until such right of
                    collection is expressly revoked by the Secured Party. Such
                    revocation may be either prior or subsequent to default.

               (b)  The Secured Party may at any time and from time to time,
                    whether prior or subsequent to default:

                    (i)  Notify any account debtors or obligors of the existence
                         of this Agreement; and

                    (ii) Direct such party to henceforth make payment directly
                         to the Secured Party of any and all sums then due to
                         become due to Debtors.

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     Upon such notice and demand, the Secured Party's receipt of any payment
shall operate as payment from the Debtors and release of any amount so paid.

          (c)  The Secured Party is authorized to endorse in the names of the
               Debtors any item of Collateral or proceeds subject to this
               Agreement, however received.

          (d)  The Secured Party may, at the Debtors' expense, enforce
               collection by suit or otherwise and may do so either in its own
               name or in the names of the Debtors, of any item of Collateral or
               proceeds subject to this Agreement. This shall include, but not
               be limited to, the right to compromise, extend or renew any
               indebtedness or to surrender, release, exchange, sell or discount
               all or any part thereof.

     10.  Default. It is agreed that the following events shall constitute a
default under this Agreement:

          (a)  Non-Payment. Any failure of EFT or the Debtors to pay when due
               any obligation secured by this Agreement shall constitute a
               default. This includes, but is not limited to, any failure to pay
               principal or interest when due, failure to pay taxes and failure
               to timely pay any note or other document evidencing obligations
               contained in this Agreement.

          (b)  Nonperformance. Any failure of the Debtors to perform or observe
               fully and in a terms of this Agreement shall constitute a
               default.

          (c)  Warranties and Representations that Prove False. Any warranty or
               representation made to the Secured Party in order to induce the
               extension of credit to the Debtors, whether made by the Debtors
               or by others on behalf of the Debtors, including agents,
               employees, sureties, guarantor, consignors and the like and
               whether such representations are contained in this Agreement or
               in related materials, such as financial guaranties, or in any
               financial instrument, including, without limitation, the
               Promissory Note executed in conjunction with this Agreement, if
               incorrect in any material respect shall operate as a default
               under this Agreement.

          (d)  Levy and Attachments. Seizure, attachment or levy on any property
               of the Debtors, whether or not such property is covered by this
               Agreement, shall operate as a default under this Agreement.

          (e)  Insolvency and the Like. It shall operate as a default under this
               Agreement if for any reason any one of the Debtors:

               (i)    becomes insolvent;

               (ii)   becomes subject to any proceeding under the bankruptcy or
                      insolvency laws, including an assignment for the benefit
                      of creditors; or

               (iii)  has its property placed under the custody of a receiver or
                      trustee.

          (f)  Alteration of Debtors' Operating Conditions. Dissolution or any
               other termination of the existence of any one of the Debtors or
               any forfeiture of its right to do business, as well as merger,
               consolidation, or the like with another, shall operate as a
               default under this Agreement.

          (g)  Unauthorized Use of Collateral or Proceeds. The assignment, sale,
               discount, transfer or use of the Collateral or its proceeds,
               except as authorized in this Agreement shall operate as a default
               under this Agreement.

     11.  Accelerate on Default. In the event of any default under this
Agreement, the entire indebtedness

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secured by the Agreement shall become immediately due and payable.

     12.  Accelerate on Insecurity. In the event the Secured Party shall deem
itself insecure, the Secured Party may, at its option, declare the entire
indebtedness secured by this Agreement immediately due and payable. Insecurity
is defined to mean a good faith belief that the prospect of payment or
performance as called for by this Agreement has become impaired.

     13.  Secured Party's Remedies. On default or acceleration, the Secured
Party shall have the following rights and remedies, which are cumulative in
nature and are immediately available to the Secured party:

          (a)   All rights and remedies provided by law, including but not
     limited to, those provided by the Uniform Commercial Code, especially those
     provided in Part 5 of Article 9;

          (b)   All rights and remedies provided in this Agreement;

          (c)   All rights and remedies provided in the Promissory Note secured
by  this Agreement; and

          (d)   All rights and remedies provided in any other applicable
security  agreement.

     Among those rights that are specifically included:

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               (i)      Right of Direct Collection. The Secured Party may, at
                        its option, notify any account debtors of the Debtors or
                        any obligor on any obligation payable to the Debtors and
                        serving as Collateral for this Agreement to make payment
                        directly to the Secured Party, and the Debtors agree to
                        cooperate fully in executing any instruments or
                        documentation deemed necessary by Secured Party in the
                        exercise of such right.

               (ii)     Right to Control Proceeds. The Secured Party may, at its
                        option, take control of any and all proceeds from such
                        direct collection and apply all "Net Proceeds" to any
                        outstanding obligations of Debtors hereunder or under
                        the Promissory Note. "Net Proceeds" shall mean all
                        proceeds collected and received from any account debtors
                        of the Debtors or any obligors on any obligations
                        payable to the Debtors, after deduction of all
                        reasonable expenses incurred in collection of such
                        accounts including, without limitation, all attorneys'
                        fees and costs incurred by Secured Party or on its
                        behalf.

               (iii)    Deficiency. The exercise of the Secured Party of its
                        right of direct collection hereunder and in application
                        of any Net Proceeds to any obligation of Debtors
                        hereunder shall in no way operate to prejudice or affect
                        in any way Secured Party's right hereunder to at any
                        time proceed directly against Debtors.

     14.  Waiver of Rights.

          (a)  All rights and remedies of the Secured Party as provided in this
               Agreement, or as found in the Promissory Note executed in
               connection with this Agreement, or arising by operation of law
               shall continue in full force and effect during the full course of
               this Agreement unless specifically waived by the Secured Party in
               a signed writing to that effect.

          (b)  Forbearance, failure, or delay on the part of the Secured Party
               in the exercise of any such right or remedy shall not constitute
               a waiver thereof and may only be effected by a specific written
               agreement to that effect which is signed by the Secured Party.

          (c)  The exercise or partial exercise of any right or remedy shall not
               preclude the further exercise of such right or remedy.

     15.  Choice of Law. This Agreement shall be governed and interpreted in
accordance with the laws of the State of Florida.
1.

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     16.  Separate Agreement. This Agreement and the Promissory Note secured
hereby shall be construed together as an agreement separate and independent of
any agreements, obligations or undertakings between the Secured Party and the
Debtors, or any of them, and the existence of any claim related to such other
agreements, obligations or undertakings between or among them shall not
constitute a defense to the enforcement of this Agreement or the Promissory Note
secured hereby, such defense(s) being expressly hereby waived by Debtors.

     17.  Severability. In the event that any provision of this Agreement shall
be found to be unenforceable in any legal proceeding, the remaining provisions
shall remain in force and effect.

     18.  Execution. This Agreement becomes effective when signed by the
Debtors.

WITNESSES:                                    DEBTORS:

                                      EARTHFIRST NEXTGAS, INC.

/s/ Beverly Mercer                    By:    /s/ John Stanton
------------------------------               -----------------------------------
                                             Its:      President
                                                       -------------------------
Beverly Mercer
------------------------------
[Print name]                          Date:   January 28, 2003
                                              ----------------------------------

                                      GIBSONTON PROPERTY, INC.

/s/ Beverly Mercer                    By:    /s/ John Stanton
------------------------------               -----------------------------------
                                             Its:      President
                                                       -------------------------
Beverly Mercer
------------------------------
[Print name]                          Date:   January 28, 2003
                                              ----------------------------------

                                      EARTHFIRST RESOURCES, INC.

/s/ Beverly Mercer                    By:    /s/ John Stanton
------------------------------               -----------------------------------
                                             Its:      President
                                                       -------------------------
Beverly Mercer
------------------------------
[Print name]                          Date:   January 28, 2003
                                              ----------------------------------

                                                        SECURED PARTY:

                                      FLORIDA ENGINEERED CONSTRUCTION
                                      PRODUCTS CORPORATION

/s/ Beverly Mercer                    By:    /s/ John Stanton
------------------------------               -----------------------------------
                                             Its:      President
                                                       -------------------------
Beverly Mercer
------------------------------
[Print name]                          Date:   January 28, 2003
                                              ----------------------------------<PAGE>
                                                                    Exhibit 10.1

                               FIRST AMENDMENT TO
                              EMPLOYMENT AGREEMENT

         This First Amendment dated as of March 31, 2003, to the Employment
Agreement dated March 11, 2002 (the "Agreement"), between US Airways, Inc., a
Delaware corporation (the "Company"), and David N. Siegel (the "Executive") is
entered into as of the date first stated above.

         WHEREAS, the Company and the Executive have previously entered into the
Agreement; and

         WHEREAS, the Company and the Executive desire to amend the Agreement as
set forth herein.

         NOW THEREFORE, the following amendments are hereby made to the
Agreement:

         1. Section 2 of the Agreement is hereby amended by the addition of the
following language at the end thereof:

         "Notwithstanding the foregoing provisions of this Section 2, no `Change
         of Control' shall be deemed to have occurred in connection with
         transactions under the Retirement Systems of Alabama investment
         agreement dated September 26, 2002, as amended, or in connection with
         the Company's emergence from bankruptcy."

<PAGE>

         2. Section 4(b)(vi) of the Agreement is hereby amended by adding the
following new sentence at the end thereof:

         "Without limiting the generality of the foregoing, effective January
         15, 2003 the travel privileges provided to the Executive shall include
         the right to receive annually during the Employment Period positive
         space travel for otherwise non-eligible family members and unrelated
         persons and a tax gross up on the value of such travel subject to a
         $25,000 annual maximum on the tax gross up amount."

         3. Section 5(d) of the Agreement is hereby amended by eliminating the
word "or" at the end of Section 5(d)(v), by substituting "; or" for the period
at the end of Section 5(d)(vi), and by the addition of the following as Sections
5(d)(vii) and 5(d)(viii):

         "(vii) any relocation of the Company's corporate headquarters outside
         of the Washington, D.C. metropolitan area; or

         "(viii) the termination by the Executive of his own employment during
         the period starting on the first anniversary of the date the Company
         emerges from bankruptcy (the `Emergence Date') and ending on the last
         day of the thirteenth complete month following the Emergence Date (the
         `Emergence Window Period'); provided, however, that a `Good Reason'
         termination pursuant to this Section 4(d)(viii) shall be treated as a
         termination prior to a Change in Control for purposes of Section 6
         hereof."

                                       2

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         4. Section 6(d)(1)(i)(C) is amended in its entirety to read as follows:

         "the product of (x) three and (y) the sum of (i) the Highest Base
         Salary and (ii) the Executive's "target bonus" under the Incentive
         Compensation Plan for the year in which termination occurs; and"

                                       US AIRWAYS, INC.

                                       By /s/ Jennifer C. McGarey
                                          -------------------------------------
                                          Name:  Jennifer C. McGarey
                                          Title: Vice President,
                                                 Deputy General Counsel &
                                                 Secretary

                                       EXECUTIVE

                                       /s/ David N. Siegel
                                       ----------------------------------------
                                       David N. Siegel

                                       3

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