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                                                                    EXHIBIT 10.2

                                SECOND AMENDMENT
                                       TO
                                OMNIBUS AGREEMENT

This Second Amendment ("Amendment") is made this 11th day of April 2002 to that
certain Omnibus Agreement among The Williams Companies Inc., a Delaware
corporation, Williams Energy Services, LLC, a Delaware limited liability
company, Williams Natural Gas Liquids, Inc., a Delaware corporation, Williams
Pipe Line Company, LLC, a Delaware limited liability company, Williams
Information Services Corporation, a Delaware limited liability company, Williams
Energy Partners, LP, a Delaware limited partnership, Williams GP LLC, a Delaware
limited liability company, and Williams OLP, LP, a Delaware limited partnership,
as amended by the first amendment thereto dated January 28, 2002 (the "Omnibus
Agreement").

WHEREAS on and effective as of the Effective Date, WES contributed and the MLP
acquired all of the membership interests in Williams Pipe Line; and

WHEREAS the parties desire to amend the Omnibus Agreement to evidence their
understanding as to pursuit of business opportunities, expense reimbursements
and other matters following the contribution of Williams Pipe Line to the MLP;

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

          1.   DEFINITIONS.

               (a)  Capitalized terms used herein but not defined shall have the
                    meaning given them in the Omnibus Agreement.

               (b)  The following definitions are added to Article I of the
                    Omnibus Agreement:

                    "Blendstocks" means isobutane, normal butane, natural
                    gasoline, and refinery grade butane.

                    "Effective Date" means the date WES contributed and the MLP
                    acquired all of the membership interests in Williams Pipe
                    Line.

                    "MAPL" means the Mid-America Pipe Line .


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                    "NGL" means natural gas liquids and includes ethane,
                    propane, naptha and Blendstocks.

                    "Refined Products" means all grades of motor gasoline,
                    distillate and aviation fuel.

                    "Restricted Assets" means assets or any business having
                    assets engaged or obligated to engage in the activities
                    prohibited by Section 2.1(a) or 2.1(b) .

                    "Partnership Restricted Assets" means assets or any business
                    having assets engaged or obligated to engage in the
                    activities prohibited by Section 2.4(a), 2.4(b), 2.4(c) or
                    2.4(d) as of the Effective Date.

               (c)  The following definitions in Article I of the Omnibus
                    Agreement are amended in their entirety to read as follows:

                    "Licensors" means, for purposes of Article V hereof,
                    Williams and WISC.

                    "Partnership Entities" means the General Partner, the MLP,
                    the OLP, Williams Pipe Line and any Person controlled by any
                    of the foregoing.

2. Section 2.1 of the Omnibus Agreement is amended in its entirety to read as
follows:

"2.1 Williams Entities Restrictions. (a) During the Applicable Period, each of
the Williams Entities shall be prohibited from engaging in or acquiring any
business having assets engaged in the following activities:

          (i) the transportation, storage or distribution of ammonia or related
          products in the United States; and

          (ii) the ownership and operation of facilities for the terminalling
          and storage of refined petroleum products in any state in the United
          States, except Alaska and Hawaii.

(b) Until the earlier of April 1, 2005 or the termination of the Applicable
Period, each of the Williams Entities shall be prohibited from engaging in or
acquiring any business having assets engaged in the following activities:


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          (i) Refined Product transportation (including through joint tariff
          arrangements or capacity leases or otherwise) to a delivery point
          within a 50-mile radius of a Refined Products delivery point owned or
          supplied by a Partnership Entity on the Effective Date; and

          (ii) Refinery grade butane transportation from the Koch Pine Bend, MN,
          refinery, Marathon St. Paul, MN refinery, ExxonMobil Joilet refinery,
          BP Whiting, IN refinery and CITGO Lemont, IL refinery. ."

3. Section 2.2(a) of the Omnibus Agreement is amended in its entirety to read as
follows:

"(a) The Restricted Asset was owned, leased or operated by the Williams Entities
on the Effective Date."

4. A new Section 2.4 is added to the Omnibus Agreement that reads as follows:

"2.4 Partnership Entities Restrictions. Until the earlier of April 1, 2005 or
the termination of the Applicable Period, each of the Partnership Entities shall
be prohibited from engaging in or acquiring any business having assets engaged
in the following activities:

         (a) NGL transportation (including through joint tariff arrangements or
capacity leases or otherwise) to a delivery point within a 50-mile radius of a
NGL delivery point owned or supplied by a Williams Entity on the Effective Date;

         (b) Propane transportation into Williams Pipe Line's Carthage, MO
terminal other than on MAPL;

         (c) Blendstock transportation into Williams Pipe Line's El Dorado, KS
connection point other than on MAPL; and

         (d) Construct or otherwise acquire any connection to the Cochin
pipeline system."

5. A new Section 2.5 is added to the Omnibus Agreement that reads as follows:

"2.5 Partnership Permitted Exceptions. Notwithstanding any provision of Section
2.4 to the contrary, a Partnership Entity may own and operate Partnership
Restricted Assets under the following circumstances:

         (a) The Partnership Restricted Assets were owned, leased or operated by
the Partnership Entities on the Effective Date.

         (b) The value of the Partnership Restricted Assets acquired in a
transaction does not exceed $20 million at the time of the acquisition, as
determined by the General Partner, in its sole discretion.


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         (c) (i) The value of the Partnership Restricted Assets acquired in a
transaction exceeds $20 million at the time of acquisition, as determined by the
General Partner, in its sole discretion and (ii) WES has elected not to pursue
such opportunity in accordance with the procedures set forth in Section 2.6.

         (d) The original cost of Partnership Restricted Assets constructed does
not exceed $20 million, as determined by the General Partner, in its sole
discretion.

(e) (i) The original cost of the Partnership Restricted Assets constructed by a
Partnership Entity exceeds $20 million, as determined by the General Partner, in
its sole discretion and (ii) WES has elected not to pursue such opportunity in
accordance with the procedures set forth in Section 2.6."

6. A new Section 2.6 is added to the Omnibus Agreement that reads as follows:

"2.6 Partnership Restricted Asset Procedures. In the event that any of the
Partnership Entities acquires or constructs Partnership Restricted Assets valued
or having an original cost in excess of $20 million at the time of the
acquisition or the completion of construction, as determined by the General
Partner, then not later than six months after the consummation of the
acquisition and not later than one year after the completion of construction by
such Partnership Entity of the Partnership Restricted Assets, such Partnership
Entity shall notify WES of such purchase or construction and offer WES the
opportunity to purchase such Partnership Restricted Assets. As soon as
practicable, but in any event, within 60 days after receipt of such
notification, WES shall notify the Partnership Entity that either (i) WES has
elected not to purchase such Partnership Restricted Assets, in which event the
Partnership Entity shall be forever free to continue to own or operate such
Partnership Restricted Assets, or (ii) WES has elected to purchase such
Partnership Restricted Assets, in which event the following procedures shall be
followed:

(a) Within 30 days of receipt of the notice from WES that it has elected to
purchase the Partnership Restricted Assets, the Partnership Entity shall submit
an offer, approved by the General Partner and the Conflicts Committee, to sell
the Partnership Restricted Assets (the "Offer") to WES on the terms and for the
consideration stated in the Offer.

(b) The Partnership Entity and WES shall negotiate after receipt of such Offer
the terms on which the Partnership Restricted Assets will be sold to WES. The
Partnership Entity shall provide all information concerning the business,
operations and finances of such Partnership Restricted Assets as may be
reasonably requested by WES.

          (i) If the Partnership Entity, with the approval of the General
          Partner and the Conflicts Committee, and WES agree on such terms
          within 60 days after receipt of the Offer, WES shall purchase the
          Partnership Restricted Assets on such terms as soon as commercially
          practicable after such agreement has been reached.


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          (ii) If the Partnership Entity and WES are unable to agree on the
          terms of a sale during the 60-day period after receipt of the Offer,
          the Partnership Entity and WES will engage an independent investment
          banking firm with a national reputation to determine the fair market
          value of the Partnership Restricted Assets. In determining the fair
          market value of the Partnership Restricted Assets, the investment
          banking firm will have access to the proposed sale and purchase values
          for the Partnership Restricted Assets submitted by the Partnership
          Entity and WES, respectively. Such investment banking firm will
          determine the value of the Partnership Restricted Assets within 30
          days and furnish the Partnership Entity and WES its opinion of such
          value. The fees of the investment banking firm's appraisal will be
          split equally between Williams and the MLP. Upon receipt of such
          opinion, WES will have the option, but not the obligation, to:

          (A) purchase the Partnership Restricted Assets in accordance with the
          following process:

               (1) if the valuation of the investment banking firm is in the
          range between the proposed sale/purchase values of the Partnership
          Entity and WES, WES will have the right to purchase the Partnership
          Restricted Assets at the valuation submitted by the investment banking
          firm;

               (2) if the valuation of the investment banking firm is less than
          the proposed purchase value submitted by WES, WES will have the right
          to purchase the Partnership Restricted Assets for the amount submitted
          by WES; and

               (3) if the valuation of the investment banking firm is greater
          than the proposed sale value submitted by the Partnership Entity, WES
          will have the right to purchase the Partnership Restricted Assets for
          the amount submitted by the Partnership Entity; or

          (B) decline to purchase such Partnership Restricted Assets, in which
          event the Partnership Entity forever will be free to continue to own
          and operate such Partnership Restricted Assets."

7. Section 2.4 of the Omnibus Agreement is renumbered as Section 2.7 and the
following sentence is added:

                  "Except as provided in this Article II and the Partnership
                  Agreement, as amended, each Partnership Entity shall be free
                  to engage in any business activity whatsoever, including those
                  that may be in direct competition with any Williams Entity."

8. Section 2.5 of the Omnibus Agreement is renumbered as Section 2.8 and the
following sentences are added:


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          "The Partnership Entities agree and acknowledge that the Williams
          Entities do not have an adequate remedy at law for breach by the
          Partnership Entities of the covenants and agreements set forth in this
          Article II, and that any breach by the Partnership Entities of the
          covenants and agreements set forth in Article II would result in
          irreparable injury to the Williams Entities. The Partnership Entities
          further agree and acknowledge that any Williams Entity may, in
          addition to the other remedies which may be available to the Williams
          Entities, file a suit in equity to enjoin the Partnership Entities
          from such breach and consent to the issuance of injunctive relief
          under this Agreement."

9. A new Section 2.9 is added to the Omnibus Agreement that reads as follows:

         "2.9 Joint Tariffs. Until April 1, 2005, the Williams Entities and the
Partnership Entities Agree to use commercially reasonable efforts to maintain
the joint tariffs that existed between Williams Pipe Line and MAPL as of the
Effective Date (including using commercially reasonable efforts to maintain the
lease of the ARANCO pipeline)."

10. Section 4.1 of the Omnibus Agreement is amended to read as follows:

          "4.1 Initial General and Administrative Expenses. The initial general
          and administrative expenses, excluding general and administrative
          expenses related to Williams Pipe Line, to be reimbursed by the
          Partnership Group to Williams will not exceed $6 million for the year
          2001, excluding expenses associated with any one-time award of WEG
          restricted units under the Williams Energy Partners Long Term
          Incentive Plan (the "Baseline G&A"). The Baseline G&A will be prorated
          to reflect the actual number of months for which services are actually
          provided to the Partnership Group by Williams, including the entirety
          of the month in which such services begin."

11.  Section 4.2 (b) of the Omnibus Agreement is deleted in its entirety. New
     Sections 4.3 and 4.4 reading as follows are added following Section 4.2:

               "4.3 Williams Pipe Line General and Administrative Expenses. (a)
                    The general and administrative expenses related to Williams
                    Pipe Line to be reimbursed by the Partnership Group to
                    Williams will not exceed $30 million for the year 2002,
                    excluding expenses associated with any one-time award of WEG
                    restricted units under the Williams Energy Partners Long
                    Term Incentive Plan ("Pipe Line G&A"). The Pipe Line G&A
                    will be prorated to reflect the actual number of weeks for
                    which services related to Williams Pipe Line are actually
                    provided to the Partnership Group by Williams, including the
                    entirety of the week in which such services begin.

                    (b) The Pipe Line G&A may increase only as follows:


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                           (i) Beginning with the fiscal year beginning January
                           1, 2003 through the fiscal year ending December 31,
                           2017, the Pipe Line G&A (as adjusted annually in
                           accordance with this Article IV) may be increased by
                           no more than the lesser of 2.5% per year or the
                           percentage increase in the Consumer Price Index - All
                           Urban Consumers, U.S. City Average, Not Seasonally
                           Adjusted.

                           (ii) Beginning with the fiscal year beginning January
                           1, 2018 the Pipe Line G&A (as adjusted annually in
                           accordance with this Article IV) may be increased at
                           the discretion of the General Partner up to 20% per
                           year until the Pipe Line G&A equals the actual
                           general and administrative expenses directly charged
                           or allocated to the General Partner by Williams for
                           Williams Pipe Line.

               4.4  Subsequent Acquisitions. If the Partnership Group makes a
                    subsequent acquisition, general and administrative expenses
                    to be reimbursed by the Partnership Group will be increased
                    by the amount of general and administrative expense included
                    in the valuation of such acquisition made by the General
                    Partner on a pro forma basis for the succeeding four fiscal
                    quarters. The portion of this pro forma amount that is
                    proportionate to the remainder of the MLP fiscal year in
                    which the acquisition is made will be added to the general
                    and administrative expenses payable for that year. General
                    and administrative expenses to be reimbursed by the
                    Partnership Group will be increased by the entire pro forma
                    amount in succeeding fiscal years."

13.  Section 6.1 of the Omnibus Agreement is deleted in its entirety and the
     following substituted therefor:

                    "Williams Reimbursement of Partnership Group Maintenance
                    Expenditures. (a) Williams will reimburse the Partnership
                    Group for maintenance capital expenditures made by the
                    Partnership Group in fiscal years 2001 and 2002 to maintain
                    the Assets to the extent such expenditures in either of
                    those years exceed $4.9 million, provided Williams shall not
                    be required to reimburse more than an aggregate of $15
                    million under this Section 6.1(a).

                    (b) Williams will reimburse the Partnership Group for
                    maintenance capital expenditures made by the Partnership
                    Group in fiscal years 2002, 2003, and 2004 to maintain
                    assets owned by Williams Pipe Line to the extent that such
                    expenditures in any of those years exceed $19 million,
                    provided Williams shall not be required to reimburse more
                    than an aggregate of $15 million under this Section 6.1
                    (b)."


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14. Section 7.4 of the Omnibus Agreement is amended in its entirety to read as
follows:

          "7.4 Termination. (a) This Agreement will terminate upon a Change in
          Control of the General Partner. In addition, the provisions of Article
          II of this Agreement may be terminated by Williams upon a Change of
          Control of Williams. In the event of termination of this Agreement,
          the Licensees' right to utilize or possess the Software and the Marks
          licensed under this Agreement shall automatically cease. Within 15
          days after the termination of this Agreement, the Licensees shall (i)
          return to Licensors or destroy the original and all copies, in any
          form, of all Software and Inventions, or parts thereof, for which it
          has received a license hereunder and (ii) provide a certified
          affidavit executed by an officer of the Licensees to the effect that
          the destruction has been completed.

          (b) Section 7.4(a) notwithstanding, in the event of termination of
          this Agreement, the MLP may, at its option, require the Licensors to
          transfer all right, title, and interest in Automated Transportation
          Logistics Activity System a/k/a "Atlas 2000" to Williams Pipe Line at
          no cost."

15. Except as expressly amended hereby, the Omnibus Agreement shall remain in
full force and effect without modification.

16. (a) Negotiation of Rights of Limited Partners, Assignees, and Third Parties.
The provisions of this Amendment are enforceable solely by the parties to this
Amendment, and no Limited Partner, Assignee or other Person of the MLP or the
OLP shall have the right, separate and apart from the MLP or the OLP, to enforce
any provision of this Amendment or to compel any party to this Amendment to
comply with the terms of this Amendment.

(b) Counterparts. This Amendment may be executed in any number of counterparts
with the same effect as if all signatory parties had signed the same document.
All counterparts shall be construed together and shall constitute one and the
same instrument.

(c) Severability. If any provision of this Amendment or the application thereof
to any Person or circumstance shall be held invalid or unenforceable to any
extent, the remainder of this Amendment and the application of such provision to
other Persons or circumstances shall not be affected thereby and shall be
enforced to the greatest extent permitted by law.


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         IN WITNESS WHEREOF, the parties have caused this Amendment to be
     executed as of the date first above written.

                                       THE WILLIAMS COMPANIES, INC.

                                       By:      /s/ Mark D. Wilson
                                           -------------------------------------
                                       Name:  Mark D. Wilson
                                       Title: Vice President

                                       WILLIAMS ENERGY SERVICES, LLC

                                       By:      /s/ Alan S. Armstrong
                                           -------------------------------------
                                       Name:  Alan S. Armstrong
                                       Title: Senior Vice President and General
                                              Manager- Midstream Gas and Liquids


                                       WILLIAMS NATURAL GAS LIQUIDS, INC.

                                       By:      /s/ Alan S. Armstrong
                                           -------------------------------------
                                       Name:  Alan S. Armstrong
                                       Title: Senior Vice President

                                       WILLIAMS PIPE LINE COMPANY, LLC By
                                       Williams Energy Partners L.P.,
                                        Its Managing Member

                                       By Williams GP, LLC, Its General Partner

                                       By:      /s/ Don R. Wellendorf
                                           -------------------------------------
                                       Name:  Don R. Wellendorf
                                       Title: Senior V.P., C.F.O. & Treasurer

                                       WILLIAMS INFORMATION SERVICES CORPORATION


                                       By:      /s/ Gary R. Belitz
                                           -------------------------------------
                                       Name:  Gary R. Belitz
                                       Title: Controller

                                       WILLIAMS ENERGY PARTNERS L.P.

                                       By:  WILLIAMS GP LLC, its general partner

                                       By:      /s/ Don R. Wellendorf
                                           -------------------------------------
                                       Name:  Don R. Wellendorf
                                       Title: Senior V.P., C.F.O. & Treasurer


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                                       WILLIAMS OLP, L.P.

                                       By:  WILLIAMS GP LLC, its general partner

                                       By:      /s/ Don R. Wellendorf
                                           -------------------------------------
                                       Name:  Don R. Wellendorf
                                       Title: Senior V.P., C.F.O. & Treasurer

                                       WILLIAMS GP LLC

                                       By:      /s/ Don R. Wellendorf
                                           -------------------------------------
                                       Name:  Don R. Wellendorf
                                       Title: Senior V.P., C.F.O. & Treasurer