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                                                                    EXHIBIT 10.F


                     FIFTEENTH AMENDMENT TO THE PENSION PLAN
                    FOR EMPLOYEES OF THE COASTAL CORPORATION


         THIS AMENDMENT is made the 29th day of September, 2000, by The Coastal
Corporation, a Delaware corporation (hereinafter referred to as the "Company").


                                   WITNESSETH:


         WHEREAS, the Pension Plan for Employees of The Coastal Corporation was
restated as of January 1, 1989, and has since been amended (such plan, as
restated and amended, is hereinafter referred to as the "Plan");

         WHEREAS, the Company wishes to amend the definition of "leased
employee" to clarify that the employee will receive credit for purposes of
vesting for the twelve-month period of service prior to achieving the status of
"leased employee;" and

         WHEREAS, the Company wishes to amend the Plan to provide for an offset
against benefits in the event of a criminal conviction under ERISA as permitted
by statute; and

         WHEREAS, the Company wishes to amend the Plan to clarify the provisions
with respect to the payment of benefits under qualified domestic relations
orders; and

         WHEREAS, the Company wishes to amend the Plan to increase the benefit
to be paid for years of service after 1998 in the Seventh Supplement - Coal
Supplement; and

         WHEREAS, the Company wishes to amend the Plan to add an Eleventh
Supplement, "Great Lakes Early Retirement Supplement," to provide for an early
retirement incentive program for individuals who were employees of Great Lakes
Gas Transmission Company on March 31, 2000;

         NOW, THEREFORE, the Plan is amended as follows:

1.       The first paragraph of Subsection 1.10(g) is amended to read in its
         entirety as follows:

                  "(g) A person who is not an employee of the Company, a
         Subsidiary or a Related Employer and who performs services for the
         Company, Subsidiary or Related Employer pursuant to an agreement
         between the Company, a Subsidiary or a Related Employer and a leasing
         organization shall be considered a "leased employee" after such person
         performs such services for a twelve-month period and the services are
         performed under the primary direction or control of the Company,
         Subsidiary or a Related Employer. A person who is considered a leased
         employee of the Company, a Subsidiary or a Related Employer shall not
         be considered an Employee for purposes of the Plan. If a leased
         employee subsequently becomes an Employee and thereafter participates
         in the Plan, he shall receive credit for vesting under Section 5.4 for
         the twelve-month period prior to his becoming a leased employee and his
         period of employment as a leased employee, except to the extent that
         Section 414(n)(5) of the Code was satisfied with respect to such
         Employee while he was a leased employee."

2.       The first sentence of Section 5.7(g) is amended to read in its entirety
         as follows:

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                  "Any Participant whose payments of Retirement Income are
         suspended pursuant to paragraph (d) of this Section, shall be notified
         (by personal delivery or first class mail) during the first calendar
         month in which payments are withheld, that his Retirement Income is
         suspended."

3.       Section 12.7 is amended to read in its entirety as follows:

         12.7     Interest Nontransferable.

                  "(a) Except as provided in this Section, no interest of any
         person or entity in, or right to receive distributions from, the Trust
         Fund shall be subject in any manner to sale, transfer, assignment,
         pledge, attachment, garnishment, or other alienation or encumbrance of
         any kind; nor may such interest or right to receive distributions be
         taken, either voluntarily or involuntarily, for the satisfaction of the
         debts of, or other obligations or claims against, such person or
         entity, including claims for alimony, support, separate maintenance and
         claims in bankruptcy proceedings.

                  (b) Notwithstanding the limitations of the provisions of
         subsection 12.7(a), a Participant's benefit under this Plan may be
         offset for an amount that the Participant is ordered or required to pay
         this Plan if the order or requirement to pay arises (i) under a
         judgment of conviction of crime involving this Plan, (ii) under a civil
         judgment (including a consent order or decree) entered by a court in an
         action brought in connection with a violation (or alleged violation) of
         the ERISA fiduciary responsibility provisions, or (iii) pursuant to a
         settlement agreement between the Internal Revenue Service or the
         Pension Benefit Guaranty Corporation and the Participant in connection
         with a violation (or alleged violation) of the ERISA fiduciary
         responsibility provisions by a fiduciary or other person. The judgment,
         order, decree or settlement agreement must expressly provide for the
         offset of all or part of the amount ordered or required to be paid to
         this Plan against the Participant's benefit.

                  (c) Notwithstanding the preceding provisions of this Section,
         all or any part of the Accrued Benefit of a Participant shall be
         subject to and payable in accordance with the applicable requirements
         of any Qualified Domestic Relations Order, as that term is defined in
         Section 414(p) of the Code, and the Administrator shall direct the
         Trustee to provide for payment in accordance with such Order and
         Section and any regulations promulgated under such Section. All such
         payments pursuant to Qualified Domestic Relations Orders shall be
         subject to reasonable rules and regulations promulgated by the
         Administrator; provided that such rules and regulations are consistent
         with Section 414(p) of the Code. If prior to the commencement of
         payment to a Participant of his Retirement Income, any amount of his
         Accrued Benefit is paid to an alternate payee or payees pursuant to a
         Qualified Domestic Relations Order, the amount of his Accrued Benefit
         shall be reduced by the Actuarial Equivalent of any such payment.

                  Notwithstanding any Plan provision to the contrary, an
         alternate payee pursuant to a Qualified Domestic Relations Order shall
         not receive any portion of an increase in benefits due to early
         retirement to which the Participant is or may be entitled. Any benefit
         received by such an alternate payee shall be Actuarial Equivalent of
         the portion of the benefit to which such alternate payee is entitled at
         Normal Retirement Age of the Participant reduced on an actuarial basis
         to reflect the payment at an earlier date should such alternate payee
         elect to receive benefits before the Normal Retirement Date of the
         Participant.

                  For purposes of this Section, if the Participant's benefit is
         to be paid in the form of a survivor annuity under the Plan, then (i)
         the Spouse of such Participant must provide a consent in writing,
         witnessed by a notary public or Plan representative), unless the
         Participant establishes to the satisfaction of the Administrator that
         such consent may not be obtained because there is no Spouse, the Spouse
         cannot be located, or because of such other

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         circumstances as the Secretary of the Treasury may by regulations
         prescribe, (ii) such Spouse has previously provided a consent pursuant
         to Section 6.2(d), (iii) such Spouse has been ordered or required in
         such judgment, order, decree, or settlement to pay an amount to the
         Plan in connection with the ERISA fiduciary responsibility violation,
         or (iv) such Spouse retains the right to receive the survivor annuity
         in such judgment, order, decree, or settlement.

                  For purposes of this Section, the survivor annuity payable
         pursuant to Section 6.1(a) shall be determined as if (i) the
         Participant terminated employment on the date of the offset, (ii) there
         was no offset, (iii) this Plan permitted commencement of benefits only
         on or after Normal Retirement Age, (iv) this Plan provided only the
         survivor annuity described in Section 6.1(a), and the amount of the
         Preretirement Survivor Annuity described in Section 5.5(g) is equal to
         the amount of the survivor annuity payable under Section 6.1(a).

                  The provisions of this subsection are effective for judgments,
         orders, and decrees issued and settlement agreements entered into, on
         or after December 31, 1999."

4.       Effective January 1, 1999, Section 3.1(a)(iii) of the Seventh
         Supplement - Coal Supplement is revised and a new Section 3.1(a)(iv) is
         added to read as follows in their entirety:

                  "(iii) thirty-five dollars multiplied by the Participant's
         Years of Service during 1990 through 1998.

                  (iv) forty-five dollars multiplied by the Participant's Years
         of Service after 1998."

5.       A new Eleventh Supplement, is added to read in its entirety as follows:

                              "ELEVENTH SUPPLEMENT

            GREAT LAKES EARLY RETIREMENT INCENTIVE PROGRAM SUPPLEMENT

                                    ARTICLE I

                                  INTRODUCTION

                  This Supplement is referred to as the "Great Lakes ERIP
         Supplement." This Supplement includes provisions applicable only to
         Employees (as defined in this Supplement) of Great Lakes Gas
         Transmission Company.

                  The purpose of this Supplement is to provide an early
         retirement incentive program within the Plan for Participants to whom
         this Supplement applies.

                  The provisions of the Great Lakes ERIP Supplement apply in
         lieu of inconsistent or contrary provisions contained in the Plan
         (excluding this Supplement) with respect to persons to whom this
         Supplement applies.


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                                   ARTICLE II

                                   DEFINITIONS

          Terms used in this Supplement which are defined in the Plan have the
same meaning in this Supplement unless such terms are defined differently for
purposes of this Supplement. The definition of terms defined in this Supplement
apply only to this Supplement and not to other parts of the Plan.

          2.1 "Early Retirement Incentive Program" is the modified retirement
benefits set forth in this Supplement for Employees eligible for such program
and who elect to participate.

          2.2 "Employee," for purposes of this Supplement only, has the meaning
ascribed to such term in the Plan, except that the individual must be employed
by Great Lakes on March 31, 2000.

          2.3 "Great Lakes" means Great Lakes Gas Transmission Company, a
Delaware corporation.

          2.4 "Participant," for purposes of this Supplement only, means an
Employee, as defined in this Supplement, who meets the eligibility requirements
of Section 3.1 of this Supplement.


                                   ARTICLE III

                       EARLY RETIREMENT INCENTIVE PROGRAM

         3.1 Eligibility. To be eligible to participate in the Early Retirement
Incentive Program, an Employee must have been an Employee through March 31,
2000; must have reached at least fifty-five (55) years of age on or before March
31, 2000; and must have five (5) or more Years of Service on or before March 31,
2000, for purposes of determining vesting in the Plan. To participate in the
Early Retirement Incentive Program, an Employee must make an irrevocable,
written election to retire as of March 31, 2000 and to commence receipt of
Retirement Income as of April 1, 2000. The election must be made by December 31,
1999. An Employee who has retired previous to December 31, 1999 and commenced
receiving Retirement Income under the Plan, but who has been re-employed as an
Employee on or before December 31, 1999, is eligible for the Early Retirement
Incentive Program.


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         3.2 Retirement Benefits. The Retirement Income of each Employee
eligible for the Early Retirement Incentive Program shall be determined pursuant
to provisions of the Plan applicable to such Employee, as such provisions are
modified by the provisions of this Supplement to provide the benefit determined
pursuant to subsection (a) or subsection (b), whichever is greater, plus the
benefit determined pursuant to subsection (c) of this Section:

                  (a) The Retirement Income determined by (i) increasing the
         Years of Service of the Employee by five years and (ii) increasing the
         age of the Employee by the lesser of (A) five years or (B) the number
         of years required for the Employee to attain age sixty-five (65). Note
         that the Basic Compensation, Final Average Earnings and other
         Compensation used to calculate the Retirement Income shall not be
         altered or projected due to the age and Years of Service additions of
         this subsection (a). In addition, the optional forms of benefit which
         may be selected by the Employee shall be determined by the actual age
         of the Employee at April 1, 2000, without the addition of up to five
         years, as described in this subsection.

                  (b) The Retirement Income determined without regard to the
         reduction for commencement of payments prior to the Normal Retirement
         date of the Employee. This includes reductions specified in the Plan
         and the Supplements, including, without limitation, Section 5.3 of the
         Plan and the Third Supplement, ANR Supplement.

                  (c) (i) For Employees under age 62 on April 1, 2000. A monthly
                  amount equal to the monthly Social Security benefit the
                  Employee would be entitled to receive at age sixty-two (62),
                  assuming the Employee continued to receive Compensation at the
                  same rate as in effect at April 1, 2000, reflecting the law in
                  effect at January 1, 2000 without adjustment for cost of
                  living or other increases or decreases in the benefit amount
                  which adjustments would have been first applicable after
                  January 1, 2000.

                           (ii) For Employees age 62 or older on April 1, 2000.
                  A monthly amount equal to the monthly Social Security benefit
                  the Employee would have been entitled to on January 1, 2000,
                  assuming the Employee had elected to commence receipt of
                  Social Security benefits at age sixty-two (62), without
                  adjustment for cost of living or other increases or decreases
                  in the benefit amount which adjustments would have been first
                  applicable after January 1, 2000.

                           (iii) The monthly amount will be paid commencing on
                  April 1, 2000 for the greater of (i) twenty-four months or
                  (ii) the number of months up to and including the month the
                  Participant reaches, or would have reached, age sixty-two
                  (62).

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                           (iv) Each Employee who has attained the age of
                  sixty-three (63) years on or before March 31, 2000 shall have
                  the option of receiving such amount in the form of a 50% Joint
                  and Survivor Annuity in lieu of the twenty-four (24) monthly
                  payments.

                  (d) The reduction in Retirement Income due to coverage under
         the Preretirement Survivor Annuity provisions of the Plan (including
         reductions pursuant to Section 5.5) and other Supplements, excluding
         this Supplement, shall apply only to the Retirement Income determined
         pursuant to provisions of the Plan, excluding this Supplement, and
         shall not apply to any additions to Retirement Income provided by this
         Supplement, including provisions of subsections 3.2 (a), (b) and (c) of
         this Supplement.

                  (e) The Retirement Income of the Participant will be the total
         of the amounts determined pursuant to subsections (a) or (b), whichever
         is greater, and (c) of this Section. There shall be no duplication of
         benefits from the Plan with respect to Years of Service taken into
         account in the Retirement Income calculations described in this
         Section.

                  (f) The limitations contained in the Plan with respect to
         qualifications of the Plan pursuant to the applicable laws and
         provisions of the Plan derived therefrom (including provisions of
         Section 5.8) shall apply to the Retirement Income determined pursuant
         to this Supplement and such Retirement Income shall be reduced as
         necessary to comply with such provisions.

                  The provisions of this Supplement shall be modified to the
         extent necessary to comply with federal laws and regulations and are
         conditioned upon the issuance of a favorable determination of
         qualification letter by the Internal Revenue Service. To the extent
         necessary to comply with requirements for qualification, provisions of
         this Supplement shall be modified to comply with such requirements, and
         such modifications shall be on a retroactive basis, if necessary.

         3.3 Effective Date. The effective date for Retirement Income to
commence for Employees electing to participate in the Early Retirement Incentive
Program is April 1, 2000."

6.       Except for the preceding, all of the terms of the Plan shall remain in
         full force and effect.


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7.       This Amendment may be executed in any number of counterparts and by
         different parties hereto on separate counterparts, each of which, when
         so executed and delivered shall be an original, but all such
         counterparts shall together constitute one and the same instrument.

         IN WITNESS WHEREOF, the Company has caused this instrument to be
executed by its duly authorized officers and its seal to be affixed hereto as of
the date indicated above and the provisions of this Amendment shall be effective
as of the date indicated above, unless otherwise stated or required by law.

ATTEST:                                THE COASTAL CORPORATION
(Seal)

__________________________________     By: _____________________________________
Austin M. O'Toole                      David A. Arledge
Senior Vice President and Secretary    President and Chief Executive Officer


ATTEST:                                GREAT LAKES GAS TRANSMISSION
(Seal)                                    COMPANY


__________________________________     By:______________________________________
John J. Wallbillich                    Michael Durnin
Vice President - Legal and             President and Chief Executive Officer
Environmental Affairs and
Assistant Secretary


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