<PAGE>

                                                                EXHIBIT 10.13(h)

                                                                   HATTIESBURG-A

                             200,000 SUBSCRIBED IN
                                    PHASE I.

                                  FIRM STANDBY

                              GAS STORAGE CONTRACT

                                 BY AND BETWEEN

                    HATTIESBURG INDUSTRIAL GAS SALES COMPANY

                                       AND

                         MISSISSIPPI VALLEY GAS COMPANY

                                    EFFECTIVE

                                FEBRUARY 21, 1990

                                     PART A*

*   This Contract for 200,000 MQS ("Part A") is issued, together with a second
    contract for 100,000 MQS ("Part B"), in replacement of the original Firm
    Standby Gas Storage Contract for 300,000 MQS dated February 21, 1990.

<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                 FIRM STANDBY GAS STORAGE CONTRACT
<S>                                                                                                              <C>
I.       ACQUISITION AND CONSTRUCTION  ..................................................................         2

II.      GAS TO BE STORED AND DELIVERED..................................................................         4

III.     SCHEDULING......................................................................................         6

IV.      POINT(S) OF DELIVERY AND REDELIVERY ............................................................         8

V.       TERM............................................................................................         8

VI.      RATES...........................................................................................         9

VII.     NOTICES.........................................................................................        13

VIII.    GENERAL TERMS AND CONDITIONS....................................................................        15

IX.      ADDITIONAL STORAGE OPTION.......................................................................        15

X.       MISCELLANEOUS...................................................................................        16

                                                             Exhibit "A"
                                                    General Terms and Conditions

I.       DEFINITIONS.....................................................................................         1

II.      QUALITY.........................................................................................         3

III.     PRESSURE .......................................................................................         4

IV.      TITLE AND RISK OF LOSS..........................................................................         4

V.       MEASUREMENT.....................................................................................         6

VI.      BILLINGS AND PAYMENTS...........................................................................         9

VII.     TAXES..........................................................................................         10

VIII.    REGULATORY BODIES...............................................................................        13

IX.      FORCE MAJEURE...................................................................................        14

X.       DEFAULT AND TERMINATION.........................................................................        16

                                                             Exhibit "B"
                                                 Point(s) of Delivery and Redelivery
</TABLE>

<PAGE>

                              GAS STORAGE CONTRACT

         THIS GAS STORAGE CONTRACT (hereinafter referred to as the "Contract")
is made effective as of the 21st day of February, 1990, by and between
HATTIESBURG INDUSTRIAL GAS SALES COMPANY, a Delaware corporation, (f/k/a Endevco
Industrial Gas Sales Company) (herein referred to as "Company"), operator of the
Storage Facilities (as defined below) and managing general partner of the
Hattiesburg Gas Storage Company, the owner of the said Storage Facilities, and
MISSISSIPPI VALLEY GAS COMPANY, a Mississippi corporation (herein referred to as
"Customer").

                              W I T N E S S E T H:

         WHEREAS, Company and Customer are parties to a "Precedent Agreement"
dated October 13, 1989, wherein Company and Customer agreed, upon the
satisfaction of certain conditions, to enter into this Contract; and

         WHEREAS, the conditions in the Precedent Agreement have been satisfied
or waived; and

         WHEREAS, subject to the terms hereof, Company will acquire certain
caverns located near Petal, Mississippi and develop such caverns into
underground natural gas storage facilities (hereinafter referred to as the
"Storage Facilities") initially having a usable storage capacity of
approximately two billion cubic feet ("Phase I"), and which may, at Company's
discretion, subsequently be expanded to a capacity of approximately five billion
cubic feet of usable storage capacity ("Phase II"); and

<PAGE>

         WHEREAS, Company will install and construct all facilities necessary to
connect the Storage Facilities with the Point(s) of Delivery and Point(s) of
Redelivery herein specified; and

         WHEREAS, Customer desires that Company receive, on a firm basis, at the
Points of Delivery herein specified, certain quantities of gas from the pipeline
facilities of Transcontinental Gas Pipe Line Corporation ("Transco") and/or
Tennessee Gas Pipeline Company ("Tennessee") for the purpose of injecting and
storing such gas for Customer or for its account in such Storage Facilities, and
that Company redeliver such gas, on a firm basis, into the facilities of said
pipeline companies, at the Points of Redelivery herein specified; and

         WHEREAS, Company desires to perform such services for Customer, all to
be provided pursuant and subject to the terms and conditions hereof;

         NOW, THEREFORE, for and in consideration of the mutual covenants herein
contained, together with other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged and confessed by both parties
hereto, Company and Customer hereby agree as follows:

                                    ARTICLE I

                          ACQUISITION AND CONSTRUCTION

         Within thirty (30) days after the execution hereof, Company shall
endeavor to close its purchase of the Storage Facilities, on terms and
conditions satisfactory to Company. Thereafter, Company shall commence the
construction and development of the Storage Facilities and shall provide
Customer written notice of the

                                        2

<PAGE>

commencement of construction and the date upon which Company anticipates that
such facilities will be operational. Upon completion of construction, including
testing, as required by all applicable federal, state and/or applicable codes,
and all other matters required for operation, Company shall provide Customer
written notice that said facilities are fully operational and shall state in
such notice a date upon which Company will be ready to receive gas for storage,
which date shall be not less than thirty (30) days following such notice (such
date to be hereinafter referred to as the "Commencement Date"). If the
Commencement Date does not occur on or before December 1, 1990, or such later
date as may be agreed upon, (subject to a day for day extension for delays
caused by an event(s) of "force majeure" as herein defined and for each day
after March 8, 1990 which expires prior to the date that Company receives
executed Firm Storage Contracts covering at least 165,000 MMBtu of MDWQ, as
herein defined), for any reason, including, without limitation, Company's
inability to close its purchase of the Storage Facilities on terms acceptable to
Company, then either party shall have the right to terminate this Contract,
without further liability or obligation to the other party hereunder, by
providing the other party thirty (30) days prior written notice. Notwithstanding
the foregoing, in the event that Customer gives notice of termination in
accordance with the above and, thereafter, Company provides written notice to
Customer stating a Commencement Date which will occur prior to the expiration of
such thirty (30) day period, then, Customer's notice of termination shall be
void and of no further force or effect and

                                        3

<PAGE>

this Contract shall continue in accordance with its terms, unless Company is
unable to commence service on the Commencement Date stated in its notice.

                                   ARTICLE II

                         GAS TO BE STORED AND DELIVERED

         2.1      Subject to the terms and provisions of this Contract, Company
agrees to reserve for service to Customer a portion of the Storage Facilities.
The capacities so reserved for Customer shall be sufficient to enable Customer
to inject gas into, withdraw gas from, and store gas in the Storage Facilities,
in quantities up to the maximum quantities set forth below:

         (i)      a maximum daily withdrawal quantity ("MDWQ") of 20,000 MMBtu
                  per day;

         (ii)     a maximum daily injection quantity ("MDIQ") of 10,000 MMBtu
                  per day;

         (iii)    a maximum capacity in the Storage Facilities ("MQS") equal to
                  200,000 MMBtu.

         2.2      Customer shall tender or cause to be tendered to Company at
the Point(s) of Delivery any gas which Customer desires to have injected into
storage hereunder. Customer shall also receive or cause to be received gas
requested to be withdrawn from storage at the Point(s) of Redelivery upon tender
for redelivery by Company.

         2.3      Subject to the operating conditions of the pipelines
delivering or receiving gas for Customer's account, Company shall receive gas
for injection from Customer at the Point(s) of Delivery and redeliver gas to
Customer at the Point(s) of Redelivery as scheduled by Customer from time to
time; provided that Company

                                        4

<PAGE>

shall not be obligated to receive for injection any quantity of gas if the
injection of the same would cause the quantity of gas stored in the Storage
Facilities for Customer's account ("Customer's Gas Storage Inventory") to exceed
Customer's MQS as stated above; nor shall Company be obligated at any time to
deliver more gas to Customer than Customer has in its then-current Customer's
Gas Storage Inventory.

         2.4      Company shall not be obligated to receive, at any Point of
Delivery for injection, or to redeliver, at any Point of Redelivery, any
quantity of gas when the quantity of gas tendered for delivery to Company or
requested by Customer to be redelivered, together with all other volumes of gas
tendered for delivery to Company at any such Point of Delivery, or requested for
redelivery at such Point of Redelivery, is less than 5,000 MMBtu per day in the
aggregate.

         2.5      In addition to the maximum daily rates of injection and
withdrawal as specified above in Section 2.1, Company shall use its best efforts
to accommodate requests of Customer to inject or withdraw gas at greater rates
of flow and, at such Point(s) of Delivery or Point(s) or Redelivery in addition
to those specified on Exhibit "B" annexed hereto, at such times as such
additional capacities are not required for service to other firm, standby
storage customers. Any such additional services shall be provided at the rates
stated in Section 6.1(c) and 6.1(d), as may be amended by Section 6.1(e), only
as capacities are available and on a prorata basis to other firm, standby
storage customers, without obligation or liability for interruption by Company
as to any

                                        5

<PAGE>

withdrawals or injections in excess of the maximums reserved for Customer.
Additional withdrawals and/or injections will be made only to the extent that
Customer has gas in storage to be withdrawn, or unfilled capacity in the Storage
Facilities reserved as part of Customer's MQS as stated herein.

                                   ARTICLE III

                                   SCHEDULING

         3.1      At any time during any day when Customer desires Company to
receive and inject gas into, or to withdraw and deliver gas from, the Storage
Facilities, Customer shall give verbal notice in accordance with Section 3.2 of
this Article to Company's dispatcher, specifying the quantity of gas to be
injected or withdrawn and the appropriate Points of Delivery or Points of
Redelivery, as applicable. Customer shall make available and tender any gas to
be injected hereunder and receive and accept delivery, upon tender by Company,
any gas requested to be withdrawn from storage. The quantity of gas stored in
the Storage Facilities for the account of Customer shall be increased or
decreased upon injection or withdrawal of gas from storage, as applicable.
Customer shall not (unless otherwise agreed by Company), on an hourly basis,
tender for injection nor shall Company be obligated to receive gas for injection
or to withdraw and deliver gas from storage, at rates of flow in excess of 1/24
of Customer's MDIQ or MDWQ, respectively.

         3.2      Customer shall notify Company at least eight (8) hours in
advance of any requested change in the daily or hourly rate of flow for
injections or withdrawals of gas hereunder. Company may waive

                                        6

<PAGE>

any part of the eight (8) hour notice upon request if, in Company's reasonable
judgement, operating conditions permit such waiver. Customer shall notify
Company immediately of any circumstance which causes or will cause the
deliveries to or receipts from Company to be different from those requested.
Notices provided in this Article may be verbal, followed by a written
confirmation delivered via telecopy, overnight mail, first class U.S. mail, or
hand-delivery when such written confirmation is requested by either party.
Customer shall provide notice of any changes in deliveries to or receipts from
Company to all applicable transporting pipelines and shall be responsible for,
and shall indemnify and hold Company harmless from, any and all liabilities and
expenses resulting from Customer's failure to notify all applicable transporting
pipelines of any such changes.

         3.3      In the event that an imbalance occurs on the pipeline to or
from which such gas is delivered or received, which imbalance results from
Company's failure to tender the quantities of gas scheduled for delivery from
storage, or accept delivery of the quantities of gas scheduled for injection
into storage and tendered for delivery by Customer, all in accordance with and
subject to this Contract, Company shall reimburse Customer for any imbalance
penalty due and rightfully owing to the pipeline receiving or delivering the gas
at such Point(s) of Delivery or Point(s) of Redelivery, which was caused by
Company's failure to accept or deliver gas. In the event that Company is unable
to receive or deliver gas as required by this Contract and in accordance with
the request of Customer as provided above, Company shall notify

                                        7

<PAGE>

Customer as soon as practicable following any failure to receive or tender such
gas and, Customer shall, as soon as practicable following receipt of such
notice, notify and change nominations and scheduling with all pipelines and
other parties delivering or receiving gas to be delivered to or withdrawn from
storage for Customer and be reasonably diligent in taking such further actions
to prevent or minimize any imbalances from occurring. Customer and Company will
diligently work to correct any imbalance so caused prior to the end of the
applicable balancing period.

                                   ARTICLE IV

                       POINT(S) OF DELIVERY AND REDELIVERY

         4.1      The Point(s) of Delivery for all gas to be tendered by
Customer to Company for injection into the Storage Facilities shall be as
specified on Exhibit "B" attached hereto, and the maximum daily quantity of gas
which Company is obligated to receive from Customer at each individual Point of
Delivery shall not exceed the maximum stated thereon.

         4.2      The Point(s) of Redelivery for all gas to be tendered by
Company to Customer for redelivery pursuant to the terms hereof shall be as
specified on Exhibit "B", attached hereto, and the maximum quantities of gas
which Company is obligated to redeliver to Customer at each such Point of
Redelivery shall not exceed the maximum stated thereon.

                                    ARTICLE V

                                      TERM

         5.1      This Contract shall be effective as of the date set forth at
the outset hereof and shall continue in full force and effect

                                        8

<PAGE>

for a primary term of fifteen (15) years following the Commencement Date, as
defined in Article I hereof, and year to year thereafter unless and until
terminated effective at the end of such fifteenth (15th) year or any year
thereafter by either party upon not less than thirty-six (36) months prior
written notice.

         5.2      Upon expiration hereof, Company agrees that in the event that
gas storage services are still being provided in the Storage Facilities by
Company, or any assignee of Company as provided for herein, to other customers,
then, Customer shall have the right and option to continue to receive storage
services from Company, or such assignee of Company, pursuant to terms and
conditions, and for rates and charges substantially similar to those being
offered to said other customers by Company, or such assignee of Company, at the
time of such expiration.

                                   ARTICLE VI

                                      RATES

         6.1      During the first ten (10) years following the Commencement
Date, Customer shall pay to Company each month the following charges:

                  6.1(a)   A storage charge ("D(1)") of twenty and one-half
         cents ($0.205) multiplied by Customer's MQS amount specified
         in this Agreement; plus

                  6.1(b)   A deliverability charge ("D(2)") of fifty-eight cents
         ($0.58) multiplied by Customer's MDWQ amount; plus

                  6.1(c)   One cent ($0.01) for each MMBtu of gas received by
         Company for injection into storage hereunder and one cent

                                        9

<PAGE>

         ($0.01) for each MMBtu of gas redelivered by Company to Customer
         hereunder; plus

                  6.1(d)   Customer's pro-rata share of the cost of gas consumed
         in the operation of the Storage Facilities, such to be pro rated among
         all Customers based upon the quantities of gas injected and withdrawn
         by each Customer during each month. It is presently estimated that the
         total cost of gas to be consumed in the injection and withdrawal of gas
         into and from the Storage Facilities will initially total approximately
         three cents ($0.03) per MMBtu, in the aggregate; however, the parties
         agree that this cost may change from time to time and Customer shall
         continue to bear its pro rata share of such cost. Company shall
         endeavor to operate the Storage Facilities in an efficient manner so as
         to limit the gas consumed to that quantity reasonably required. Each
         month, Company shall provide Customer a statement showing its prorata
         share of such quantity and the cost of the gas consumed in the
         operation of Storage Facilities, along with the necessary supporting
         workpapers showing the total quantity and cost of gas so consumed and
         the proration calculations. Customer shall have the option, exercisable
         upon thirty (30) days prior written notice at any time during the term
         hereof, to thereafter (during the term hereof) supply its pro-rata
         share of gas consumed, as opposed to reimbursing Company in accordance
         herewith. In the event that Customer elects to provide its pro-rata
         share of the fuel used hereunder, then, following such election,
         Company shall establish and maintain

                                       10

<PAGE>

         an account (the "Fuel Account") with Customer. Initially, one and
         one-half percent (1 1/2%) of all gas delivered to Company at the Points
         of Delivery hereunder shall be retained by Company and credited to the
         Fuel Account. Customer shall not pay any injection, withdrawal or
         storage fee as to any volumes retained by Company. At the close of each
         month, Company shall debit the Fuel Account with Customer's pro-rata
         share of the fuel gas. From time to time during the term hereof,
         Company shall have the right, upon providing Customer ten (10) days'
         prior written notice, to adjust the quantity of gas to be retained by
         Company and credited to the Fuel Account in order to reflect actual
         quantities of gas consumed in the operation of the Storage Facilities
         and, to cause the Fuel Account to be as near to zero as is practicable
         on a monthly basis. Within thirty (30) days following the termination
         hereof, Company shall deliver gas to Customer, or Customer shall
         deliver gas to Company, as is necessary to cause the Fuel Account to
         equal zero. Company shall report the status of the Fuel Account as of
         the end of the previous month with each monthly statement. Customer
         shall have the right to deliver to Company the maximum capacities set
         forth in Section 2.1(iii) in addition to the gas delivered by Customer
         for credit to the Fuel Account.

                  6.1(e)   The fees payable for each MMBtu of gas delivered to
         Company for injection and for each MMBtu of gas redelivered to Customer
         hereunder, as provided for in section 6.1(c), shall be subject to
         adjustment, upon

                                       11

<PAGE>

         application to and approval by the appropriate regulatory commission,
         to reflect increases or decreases in the cost of maintenance, supplies
         and other variable expenses incurred by Company in performing the
         services hereunder. Customer shall have the right to contest any
         increase sought hereunder before the appropriate regulatory commission.
         No such adjusted fee shall exceed, however: (i) the fee herein
         provided; multiplied by (ii) the sum of one (1) plus the percentage
         change in the Gross National Product Implicit Price Deflator (the
         "Index") for the December of the then-current calendar year as compared
         to such Index for December, 1990.

         6.2      Notwithstanding the above, in the event that Company elects to
expand the Storage Facilities as referenced in section 9.1, the rates and
charges payable hereunder during the remaining portion of the initial ten (10)
years hereof shall be redetermined such that the sum of: (a) the D(1) storage
charge, as provided in section 6.1(a); and (b) the D(2) deliverability charge,
as provided in section 6.1(b); will be reduced such that the total reservation
charges payable hereunder during each month shall not exceed eighty percent
(80%) of the total reservation charges payable hereunder prior to such expansion
and rate redetermination.

         6.3      The charges payable hereunder for the remainder of the term
hereof following the tenth (10th) year (after the Commencement Date) may be
redetermined by the appropriate regulatory body in accordance with this section
6.3. Company shall have the right, upon its election, or shall be obligated,
upon request of Customer, to submit cost-of-service information to the
appropriate regulatory

                                       12

<PAGE>

authority for a review of the rates charged hereunder and to request a
determination by such regulatory authority of a rate for the remaining term
hereof. Customer shall have the right to take part in such proceedings and to
contest the proposed rates to the full extent allowed. Company shall provide
Customer not less than thirty (30) days prior written notice of Company's intent
to file for a new rate as herein provided. In the event that the rates resulting
from such redetermination are in excess of one hundred and ten percent (110%) of
the rates specified in Section 6.1, then Customer shall have the right to
terminate this Contract upon sixty (60) days' prior written notice; provided,
however, that during such sixty (60) day period following the receipt of
Customer's notice, Company shall have the option, without obligation, to agree
to charge Customer rates which do not exceed one hundred and ten percent (110%)
of the rates set forth in Section 6.1 and, in such event, this Contract shall
continue for the remaining term. Company shall provide Customer written notice
of any such election before the expiration of said sixty (60) day period and,
shall therein specify the rate to be charged hereunder.

                                   ARTICLE VII

                                     NOTICES

         7.1      Whenever any notice, request, demand, statement or payment is
required or permitted to be given under any provision of this Contract, unless
expressly provided otherwise, such shall be in writing, signed by or on behalf
of the person giving the same, and shall be deemed to have been given and
received upon the

                                       13

<PAGE>

actual receipt (including the receipt of a telecopy or facsimile of such notice)
at the address of the parties as follows:

         Company;

         For Notices:      Hattiesburg Industrial Gas Sales Company
                           5950 Berkshire Lane
                           Suite 1400, L.B. 17
                           Dallas, Texas 75225

         Payments
         (Wire Transfer):  Union Bank of California -- Los Angeles
                           ABA # 122000496
                           For Account of Hattiesburg Gas Storage Company
                           Acct No. 0880411845

         Customer:         Mississippi Valley Gas Company
                           711 W. Capital Street
                           Jackson, Mississippi 39203

         7.2      Operating communications made by telephone or other mutually
agreeable means shall be confirmed in writing or by telecopy within two (2) days
following same if requested by either party. To facilitate such operating
communications on a daily basis, lists of names, telephone and telecopy numbers
of appropriate operating personnel shall be exchanged by and between Company and
Customer before commencement of service under this Contract. Such lists shall be
updated from time to time if changed.

         7.3      The addresses of the parties may be revised upon written
notice given in accordance herewith, designating in such writing the new address
of the party so affected.

                                       14

<PAGE>

                                  ARTICLE VIII

                          GENERAL TERMS AND CONDITIONS

         The General Terms and Conditions attached hereto as Exhibit "A" are
hereby incorporated herein and made a part of this Contract as if fully set
forth herein. Any conflict or inconsistency, either in construction or
interpretation, between the terms hereof and the General Terms and Conditions
attached hereto shall be resolved in favor of the terms hereof.

                                   ARTICLE IX

                            ADDITIONAL STORAGE OPTION

         9.1      Company anticipates that it may elect to expand the Storage
Facilities at some time following initial storage operations. In the event that
Company so elects to expand the Storage Facilities, Company hereby grants
Customer an option on a pro rata portion of any increased capacities (for
storage, withdrawal or injection) developed by Company in the Storage
Facilities. Such proportionate share shall equal (i) the total additional
capacity (for storage, withdrawal or injection) developed by Company in such
Storage Facilities multiplied by (ii) a fraction, the numerator of which shall
equal Customer's rights to such capacity hereunder (MQS, MDWQ or MDIQ) and the
denominator of which shall equal the total storage capacity (for storage,
withdrawal or injection) of the Storage Facilities immediately preceding such
increase in capacity. Customer shall exercise its option, if at all, in
accordance with section 9.2 below.

                                       15

<PAGE>

         9.2      In the event that Company makes the determination to increase
any capacity (for storage, withdrawal or injection) at the Storage Facilities,
Company shall so notify Customer in writing. Such notice shall contain the terms
and conditions upon which Company will contract with other parties for such
capacity(ies), which terms shall be similar to those provided in this Contract.
For ninety (90) days following receipt of such notice, Customer shall have the
right, without obligation, to contract for additional storage rights in the
Storage Facilities upon the terms and conditions offered by Company and
reflected in the notice or such other terms as may be agreed to by Customer and
Company. Should Customer elect to contract for such additional rights, and
provide Company with written notice of such election within such ninety (90) day
period, Company shall provide Customer with formal contracts for execution. The
failure of Customer to provide written notice to Company of its election to
contract for such additional capacity rights within such ninety (90) day period,
or the failure of Customer, following such election, to execute and return to
Company the contract provided to Customer within thirty (30) days following
Customer's receipt of same, shall be deemed a waiver of Customer's option on
such capacity(ies).

                                    ARTICLE X

                                  MISCELLANEOUS

         10.1     Headings. The subject headings of the articles and sections of
this Contract are intended for the sole purpose of convenient reference and are
not intended, nor shall the same be

                                       16

<PAGE>

construed, to be a part of this Contract or considered in any interpretation
hereof.

         10.2     Amendment. Neither this Contract nor any provisions hereof
may ever be amended, changed, modified or supplemented except by an agreement in
writing, duly executed by the party to be charged with the same.

         10.3     Waiver. No failure by either party to enforce the performance
of any obligation of the other party under this Contract shall operate as a
waiver of such obligation or default, or as a waiver of any other right or
default, whether of a like or different character.

         10.4     Choice of Law. As to all matters of construction and
interpretation, this Contract shall be interpreted, construed and governed by
the laws of the State of Texas.

         10.5     Succession. Either party may assign its rights, titles or
interests hereunder to any individual, bank, trustee, company or corporation as
security for any note, notes, bonds or other obligations or securities of such
assignor, but not otherwise, without the written consent of the other party
hereto, which consent shall not be unreasonably withheld. No assignment provided
for hereunder shall in any way operate to enlarge, alter or change any
obligation of the other party hereto nor shall the assignee be relieved of its
obligations hereunder without the express written consent of the non-assigning
party.

         10.6     Right of Examination. Both Company and Customer shall have the
right to examine, at any reasonable time, the books, records, charts and any
operating data of the other to the extent

                                       17

<PAGE>

reasonably necessary to verify the accuracy of any statement, chart or
computation made under or pursuant to the provisions of this Contract. All
books, records and charts related to any statement, charge or computation made
hereunder shall be retained and available for review or inspection for a period
of two years.

         10.7     Entire Agreement. This Contract contains the entire agreement
and understanding of the parties hereto and there are no agreements,
understandings or representations, either oral or in writing, except as set
forth herein. That certain Precedent Agreement, between Customer and Company, is
hereby expressly superseded and terminated by the execution hereof.

         10.8     Authority. Company and Customer each hereby represents and
warrants that it has the full right, power and authority to enter into this
Contract, and that this Contract will not violate the provisions of any other
contract or agreement to which it is a party.

         10.9     Reissuance of Original Contract. This Contract ("Part A"), and
another Gas Storage Contract of even date herewith specifying a MQS of 100,000
("Part B"), are issued in replacement of that certain Firm Standby Gas Storage
Contract between Customer and Company dated February 21, 1990. The replacement
of the former contract is effected for administrative purposes only, and shall
be interpreted and construed for all purposes as merely a continuation of the
original contract.

         IN WITNESS WHEREOF, the parties have executed this Contract in one or
more copies or counterparts, each of which shall constitute

                                       18

<PAGE>

and be an original of this Contract effective between the parties effective as
of the date first-above written.

                                    COMPANY:

ATTEST:

                                    HATTIESBURG INDUSTRIAL GAS SALES
                                    COMPANY

-s- [ILLEGIBLE]                     By: -s- [ILLEGIBLE]
----------------------------            --------------------------------------
                                    Its:    President


ATTEST:

                                    CUSTOMER:

                                    MISSISSIPPI VALLEY GAS COMPANY

-s- [ILLEGIBLE]                     By: -s- WARREN K. ROGERS
----------------------------            --------------------------------------
                                    Its:    Senior Vice President


                                       19

<PAGE>

                                   EXHIBIT "A"
                         TO GAS STORAGE CONTRACT BETWEEN
                    HATTIESBURG INDUSTRIAL GAS SALES COMPANY
                       AND MISSISSIPPI VALLEY GAS COMPANY
                           EFFECTIVE FEBRUARY 21, 1990

                          GENERAL TERMS AND CONDITIONS

         These General Terms and Conditions ("General Terms") are attached to
and incorporated into the above-referenced GAS STORAGE CONTRACT between
HATTIESBURG INDUSTRIAL GAS SALES COMPANY (herein referred to as "Company") and
MISSISSIPPI VALLEY GAS COMPANY, a Mississippi corporation (herein referred to as
"Customer").

                                   ARTICLE I

                                  DEFINITIONS

         For the purposes of this Contract, unless expressly stated otherwise,
the following definitions shall be applicable.

         1.1      The term "Btu" shall mean British Thermal Units.

         1.2      A "day" shall mean the twenty-four (24) hour period beginning
at 7:00 a.m. Jackson, Mississippi time on each calendar day and ending at 7:00
a.m. Jackson, Mississippi time on the following calendar day.

         1.3      "Contract" shall mean the above-referenced Gas Storage
Contract together with these General Terms and all other attachments hereto or
thereto.

         1.4      The term "gas" shall mean natural gas in its natural state,
produced from wells, including casinghead gas produced with crude oil, natural
gas from gas wells and residue gas resulting from processing both casinghead gas
and gas well gas.

General Terms - Page 1

<PAGE>

         1.5      The term "Mcf" shall mean one thousand (1,000) cubic feet at a
pressure of fifteen and twenty-five thousandths (15.025) psia and at a
temperature of sixty degrees (60 degrees) Fahrenheit.

         1.6      The term "MMBtu" shall mean 1,000,000 Btu.

         1.7      A "month" shall mean that period of time beginning at 7:00
a.m. Jackson, Mississippi time on the first day of a calendar month and ending
at 7:00 a.m. Jackson, Mississippi time on the first day of the following
calendar month; provided, that, the first month hereunder shall commence on the
first day of the calendar month in which the Commencement Date occurs, and the
last month hereunder shall end on the date that this Contract terminates.

         1.8      "Point(s) of Delivery" shall mean the point or points, as
identified on Exhibit "B" of the Contract, at which gas is received by Company
for injection into storage.

         1.9      "Point(s) of Redelivery" shall mean the point or points, as
identified on Exhibit "B" of the Contract, at which gas is tendered by Company
to Customer for delivery from storage.

         1.10     The term "psia" shall mean pounds per square inch absolute.

         1.11     The term "psig" shall mean pounds per square inch gauge.

         1.12     "Storage Facilities" shall be as defined in the "WHEREAS"
clauses of the Contract.

         1.13     The term "year" shall mean a period of twelve (12) consecutive
months.

General Terms - Page 2

<PAGE>

                                   ARTICLE II

                                    QUALITY

         The gas delivered by either party to the other hereunder shall meet the
quality specifications of the transporting pipeline which receives or delivers
such gas at the Point(s) of Delivery or Redelivery and shall, in addition, be of
such quality that it shall meet the following specifications, if such standards
are more stringent:

         a.       Be commercially free of dust, gum, gum-forming constituents,
                  gasoline, and other solid and/or liquid matter, including but
                  not limited to water, gas treating chemicals and well
                  completion fluids and debris, which may become separated from
                  the gas during transportation thereof.

          b.      Contain not more than one quarter (1/4) grain of hydrogen
                  sulphide per one hundred (100) cubic feet, as determined by
                  the cadmium sulfate quantitative test, nor more than nine (9)
                  grains of total sulfur per one hundred (100) cubic feet.

          c.      The gas delivered hereunder shall not contain more than
                  two-tenths of one percent (0.2%) by volume of oxygen, and
                  shall not contain more than two percent (2%) by volume of
                  carbon dioxide; and shall not contain more than two percent
                  (2%) by volume of nitrogen.

          d.      Have a heating value of not less than nine hundred eighty
                  (980) Btu's per cubic feet.

General Terms - Page 3

<PAGE>

         e.       Have a temperature of not more than one hundred twenty degrees
                  Fahrenheit (120 degrees F), nor less than forty degrees
                  Fahrenheit (40 degrees F).

         f.       Have been dehydrated by any method other than the use of a
                  calcium chloride as desiccant, for removal of entrained water
                  in excess of seven (7) pounds of water per million (1,000,000)
                  cubic feet of gas.

                                   ARTICLE III

                                    PRESSURE

         Company shall deliver gas to Customer from storage hereunder at
pressures sufficient to enter the transporting pipeline's facilities at the
Point(s) of Redelivery against the operating pressures maintained in such
pipeline from time to time, provided that Company shall not be required to
deliver gas at pressures in excess of 960 psig. Customer shall deliver gas to
Company for injection at the Point(s) of Delivery at the pressures as may be
available from time to time in the transporting pipeline's facilities at such
points, but in no event shall such pressures be less than 550 psig or greater
than Company's maximum allowable operating pressure.

                                   ARTICLE IV

                             TITLE AND RISK OF LOSS

         4.1      Title to the natural gas stored by Company and delivered to
Customer hereunder shall, at all times, be in Customer and, except as provided
in Section 4.2 Company makes no warranty of title whatsoever. Customer warrants
for itself, its successors and

General Terms - Page 4

<PAGE>

assigns, that it will have at the time of delivery of gas storage hereunder good
title or valid right to deliver such stored hereunder. Customer warrants for
itself, its successors and assigns, that the gas it delivers hereunder shall be
free and clear of all liens, encumbrances, or claims whatsoever; and that it
shall indemnify Company and save it harmless from all claims, actions, damages,
costs and expenses arising directly or indirectly from or with respect to the
title to gas tendered to Company hereunder.

         4.2      Company warrants that it shall neither cause nor allow any
cloud or encumbrance of any nature to arise by, through or under Company with
respect to Customer's title to any gas tendered to Company for storage, and
agrees to redeliver such gas pursuant to this Contract free from all liens and
adverse claims arising by, through or under Company, and that it will indemnify,
defend, protect, and save Customer harmless from all claims, suits, actions,
damages, costs and expenses arising directly or indirectly from the same.

         4.3      As between Customer and Company: Customer shall be in control
and possession of the gas prior to delivery to Company for injection at the
Point(s) of Delivery and after redelivery by Company to Customer at the Point(s)
of Redelivery, and, shall indemnify, defend and hold Company harmless from any
damage or injury caused thereby except for damages and injuries caused by the
negligence of Company; and, Company shall be in control and possession of the
gas after the receipt of the same for injection at the Point(s) of Delivery and
until redelivery by Company to

General Terms - Page 5

<PAGE>

Customer at the Point(s) of Redelivery, and, shall indemnify, defend and hold
Customer harmless from any damage or injury caused thereby, except for damages
and injuries caused by the negligence of Customer. The risk of loss for all gas
injected into, stored in and withdrawn from the Storage Facilities shall be and
remain with the party having control and possession of the gas as herein
provided.

                                    ARTICLE V

                                   MEASUREMENT

         5.1      The unit of volume for measurement of gas delivered hereunder
shall be one (1) cubic foot of gas at a base temperature of sixty degrees
Fahrenheit (60 degrees F) and at an absolute pressure of fifteen and twenty-five
thousandths (15.025) pounds per square inch. All fundamental constants,
observations, records, and procedures involved in determining and/or verifying
the quantity and other characteristics of gas delivered hereunder shall, unless
otherwise specified herein, be in accordance with the standards prescribed in
American Gas Association ("A.G.A.") Gas Measurement Committee Report No. 3, as
now and from time to time amended or supplemented. All measurements of gas shall
be determined by calculation into terms of such unit. All quantities given
herein, unless expressly stated otherwise, are in terms of such unit.
Notwithstanding the foregoing, it is agreed that, for all purposes, the Btu
content of the gas received and delivered by Company hereunder shall be measured
on an "as delivered" basis rather than a fully saturated or "wet" basis.

General Terms - Page 6

<PAGE>

         5.2      Company, at its sole expense, shall install, maintain and
operate, or cause to be installed, maintained and operated, the measurement
facilities required hereunder. Said measurement facilities shall be so equipped
with orifice meters, recording gauges, or other types of meters of standard make
and design commonly acceptable in the industry, as to accomplish the accurate
measurement of gas delivered hereunder. The changing of charts, calibrating and
adjustment of meters shall be done by Company or its agent.

         5.3      The accuracy of Company's measuring equipment shall be
verified by Company at least once in each thirty (30) day period. If either
party desires a special test of any measuring equipment, it will promptly notify
the other party and the parties shall then cooperate to secure a prompt
verification of the accuracy of such equipment. The expenses of any such special
test, if requested by Customer, shall be borne by Customer if the measuring
equipment tested is found to be accurate within the limit of plus or minus two
percent (2%) of error. For the purposes of measurement and meter calibration,
the atmospheric pressure shall be assumed to be fourteen and seventy-three
hundredths (14.73) pounds per square inch, irrespective of variations in natural
atmospheric pressure from time to time. Company and Customer, upon request,
shall have the right to be present at any test of any measuring equipment,
including any check measuring equipment installed by Customer at its sole
expense.

General Terms - Page 7

<PAGE>

         5.4      If upon testing, the metering equipment is found to be
inaccurate, in the aggregate, by two percent (2%) or more, either plus or minus,
registration thereof and any payment based upon such registration shall be
corrected at the rate of such inaccuracy for any period of inaccuracy which is
definitely known or agreed upon, or if not known or agreed upon, then for a
period extending back one-half (1/2) of the time elapsed since the day of the
last calibration, not exceeding, however, forty-five (45) days. Following any
test, any metering equipment found to be inaccurate to any degree shall be
adjusted immediately to measure accurately; however, if any inaccuracy is less
than two percent (2%), all prior readings and measurements shall be deemed to
be accurate and no adjustments to any prior reading shall be made. If, for any
reason, any meter is registering inaccurately or is out of service or out of
repair so that the quantity of gas delivered through such meter cannot be
ascertained or computed from the readings thereof, the quantity of gas so
delivered during such period shall be estimated and agreed upon by the parties
hereto upon the basis of the best available data determined,

         a.       by using the registration of any check measuring equipment, if
                  installed and registering accurately or in the absence of (a);

         b.       by correcting the error if the percentage of error is
                  ascertainable by calibration, test, or mathematical
                  calculation, or in the absence of both (a) and (b);

General Terms - Page 8

<PAGE>

         c.       by estimating the quantity of gas deliveries by deliveries
                  during preceding periods under similar conditions when the
                  meter was registering accurately.

         5.5      The measurement hereunder shall be corrected for deviation
from Boyle's Law at the pressure and temperature under which gas is delivered
hereunder.

                                   ARTICLE VI

                              BILLINGS AND PAYMENTS

         6.1      On or before the first (1st) day of each month, Company shall
render to Customer an invoice for the storage charge (D(1)) and the
deliverability charge (D(2)) due hereunder for such month. Customer shall pay
such invoiced amounts on or before the fifteenth (15th) day of the month for
which such charges are due.

         6.2      On the tenth (10th) day of each month, Company shall render to
Customer a statement for the preceding month properly identifying the applicable
Point(s) of Delivery and Point(s) of Redelivery and showing the total quantity
of gas received from and delivered to Customer hereunder, the amounts due
pursuant to Sections 6.1(c) and 6.1(d) of the Gas Storage Contract therefor, the
amount of Customer's gas in storage as of the close of such month, and
information sufficient to explain and support any adjustments made by Company
(in accordance with section 6.4 below) in determining the amount billed.
Customer shall pay Company the full amount reflected on the statements rendered
within fifteen (15) days of its receipt of same. If the fifteenth (15th) day
shall fall upon a weekend or legal holiday, then such payment shall

General Terms - Page 9

<PAGE>

be made on the first regular business day following such fifteenth (15th) day.

         6.3      In the event that Customer fails to pay any amounts when due,
interest shall accrue on all unpaid amounts from the date due until paid at a
rate of interest equal to the lesser of: (i) the rate of interest quoted as the
"prime rate" of NCNB Texas National Bank -- Dallas, Texas to its largest and
most credit-worthy commercial customers; or (ii) the highest legal rate of
interest allowed by law.

         6.4      In the event an error is discovered in the amount billed in
any statement rendered by Company, such error shall be adjusted within thirty
(30) days of the discovery of the error. In the event a dispute arises as to the
amount payable in any statement rendered, Customer shall pay the amount shown
payable to Company in the statement which is not in dispute. Any overcharges
collected by Company pursuant to this section 6.4 shall be remitted to Customer,
with interest, calculated as provided in section 6.3, from the date such
overcharges are received by Company until repaid. Such payment shall not be
deemed to be a waiver of the right by Customer to recoup any overpayment. All
statements shall be considered final, and any and all objections thereto be
deemed waived, unless made in writing within twenty-four (24) months of
Customer's receipt thereof.

General Terms - Page 10
<PAGE>
                                   ARTICLE VII

                                      TAXES

         7.1      Subject to the provisions of Section 7.3, Customer agrees to
pay to Company, by way of reimbursement, within fifteen (15) days of receipt of
an invoice for same (pro-rated among all customers), all new taxes enacted and
levied or imposed upon Company after the Commencement Date and, any increases in
existing taxes which may be made effective after the Commencement Date, which
arise out of the gas storage services provided hereunder. In the event that any
additional taxes or increases in taxes are imposed with respect to the storage
of gas hereunder and, should Company elect not to challenge the same, then
Customer shall be subrogated to Company's rights to challenge same.

         7.2      The term "taxes" as used herein, shall mean all taxes which
are now in existence or which may in the future be levied upon Company, or its
facilities or the storage of gas hereunder and arising out of the gas storage
services to be provided hereunder including, but not limited to, street and
alley rental tax, licenses, fees and any other taxes, charges or fees of any
kind levied, assessed or made by any governmental authority on the act, right or
privilege of transporting, handling or delivering gas or using Company's Storage
Facilities, which is measured by the volume, heating value, value of the gas, or
any fee in respect to the gas or the storage,transportation or other handling
thereof (excluding, however, real property, ad valorem, capital stock, income or
excess profit taxes, or general franchise taxes imposed

General Terms - Page 11

<PAGE>

on corporations on account of their corporate existence or on their right to do
business within the state as a foreign corporation and similar taxes).

         7.3      Customer shall not be obligated to reimburse Company pursuant
to Section 7.1 in any year in an amount in excess of five percent (5%) of the
cumulative total of the monthly demand charges paid by Customer to Company in
such year. In the event that the total of the increases in taxes and additional
taxes exceed such five percent (5%) amount, then Company shall have the option
of paying the same or of seeking a determination from the appropriate regulatory
agency that such additional taxes or increases in taxes are prudent and
appropriate for inclusion in Company's rates. Subject to the following
provisions, in the event that such regulatory agency determines that such
additional and increased taxes including, without limitation, those in excess of
said five percent (5%) amount, are appropriate for inclusion, Customer shall
have the option of either paying such approved rate increases or terminating
this Contract, upon providing Company sixty days' prior written notice;
provided, however, that upon receipt of Customer's notice of termination,
Company shall have the option, without obligation, to charge Customer an
increased amount which does not exceed such five percent (5%) amount and, in
such event, Customer's notice of termination shall be of no force or effect and
this Contract shall continue in accordance with its terms. Company shall provide
Customer written notice of any such election within such sixty (60) day period.
Customer shall be given notice and

General Terms - Page 12

<PAGE>

shall have the right to participate in such rate determination and oppose the
appropriateness of including the additional or increased taxes in Company's
rates.

                                  ARTICLE VIII

                                REGULATORY BODIES

         This Contract is subject to all present and future valid laws and
lawful orders of all regulatory bodies now or hereafter having jurisdiction of
either or both the parties; and should either of the parties, by force of any
such law or regulation imposed at any time during the term of this Contract, be
rendered unable, wholly or in part, to carry out its obligations under this
Contract, other than Customer's obligation to make payments due hereunder then,
this Contract shall continue nevertheless and shall then be deemed modified to
conform with the requirements of such law or regulation. Notwithstanding the
above, this Contract shall not be deemed to be so modified if such law or
regulation substantially and materially prohibits Company from providing
services to Customer hereunder substantially in accordance with the terms set
forth in this Contract and, in such event, Company and Customer shall negotiate
in good faith to amend the terms of this Contract such that such law or
regulation may be complied with and both Company and Customer will continue to
receive the rights and benefits herein provided. This Contract is expressly made
subject to any and all tariff and other filings made by Company and approved by
any federal or state regulatory body provided, that Company will not, without
Customer's consent, seek to alter the

General Terms - Page 13

<PAGE>

firm character of the storage services herein provided or to reduce the term of
this Contract. In the event that any regulatory body having jurisdiction over
this Contract prohibits Company from collecting rates for the services provided
hereunder which are at least equal to the rates and charges provided for in this
Contract, then Company shall have the right to terminate this Contract. In the
event that any regulatory body having jurisdiction requires Company to collect
rates for services provided hereunder which are in excess of the rates herein
provided, then Customer shall have the right to terminate this Contract.

                                   ARTICLE IX

                                  FORCE MAJEURE

         9.1      In the event of either party hereto being rendered unable,
wholly or in part, by force majeure to carry out its obligations under this
Contract, other than to make payments hereunder (except as provided in section
9.3 below), the obligations of the party, as far as they are affected by such
force majeure, shall be suspended during the continuance of any inability so
caused, but for no longer period, and such cause shall as far as possible be
remedied with all reasonable dispatch. The party so affected by such event of
force majeure shall give written notice, including reasonably full particulars
of such force majeure, in writing or by telegraph to the other party as soon as
possible but in no event more than ten (10) days after the occurrence of the
cause so relied upon.

General Terms - Page 14

<PAGE>

         9.2      The term "force majeure" as employed herein shall mean,
without limitation, acts of God, strikes, lockouts, or other industrial
disturbances, acts of the public enemy, wars, blockades, insurrection, riots,
epidemics, landslides, lightning, earthquakes, fires, storms, floods, washouts,
arrest and restraints of governments and people, civil disturbances, explosions,
breakage and/or accidents to machinery, lines or pipe, freezing of lines of
pipe, inability to obtain or delay in obtaining rights-of-way, material,
supplies, labor or permits, or refusal by pipelines, which are transporting on
customer's behalf, to receive or deliver gas hereunder. It is understood and
agreed that the settlement of strikes or lockouts shall be entirely within the
discretion of the party having the difficulty, and that the above requirements
that any force majeure shall be remedied with all reasonable dispatch shall not
require the settlement of strikes or lockouts by acceding to the demands of any
opposing party when such course is inadvisable in the discretion of the party
having the difficulty. Company shall utilize all reasonable efforts to design,
operate and maintain its facilities in a manner which minimizes the potential
for freezing of wells or lines of pipe.

         9.3      In the event that Company is, due to an event of force
majeure, as herein defined, unable to provide storage services, in whole or in
part, under this Contract, then the obligation of Customer to make payment of
demand charges hereunder shall thereafter be waived or reduced proportionately
until service is again made available hereunder.

General Terms - Page 15

<PAGE>

                                    ARTICLE X

                             DEFAULT AND TERMINATION

         10.1     If either party hereto shall fail to perform any of the
covenants or obligations imposed upon it by virtue of this Contract (except
where such failure shall be excused under any of the provisions hereof), then in
such event the other party may, at its option, terminate this Contract by
proceeding as follows: the party not in default shall cause a written notice to
be served upon the party in default, stating specifically the cause for
terminating this Contract and declaring it to be the intention of the party
giving the notice to terminate the same; whereupon, the party in default shall
have thirty (30) days after receipt of the aforesaid notice in which to remedy
or remove the cause or causes of default stated in the notice of termination and
if, within said period of thirty (30) days, the party in default does so remedy
and remove said cause or causes, and fully indemnifies the party not in default,
then such notice shall be nullified and this Contract shall continue in full
force and effect. In the event the party in default does not so remedy and
remove the cause or causes of default, or does not fully indemnify the party
giving the notice for such party's actual damages as a result of such default
within said period of thirty (30) days, then this Contract shall become null and
void from and after the expiration of said period; provided, however, that if
such default be remedied but no indemnification therefor has been made due to a
bona fide dispute between the parties as to the amount thereof, then this
Contract

General Terms - Page 16

<PAGE>

shall not terminate, but the party not in default shall have the right to seek
recovery of its actual damages as provided by law. Any termination for breach of
this Contract shall be carried out strictly in accordance with this section.
Nothing in this Section 10.1 shall be construed to limit in any way the remedies
available to either party for breach of this Contract except for the right to
terminate.

         10.2     Any cancellation of this Contract pursuant to the provisions
of this Article X shall be without prejudice to the right of the party not in
default to collect any amounts then due it and without waiver of any other
remedy to which the party not in default may be entitled.

         10.3     In the event of termination, cancellation or expiration of
this Contract and, upon such occurrence, there is gas in storage for Customer's
account, this Contract shall continue in force and effect for the sole purpose
of withdrawal and delivery of and payment for storage services of said gas for
an additional ninety (90) days.

General Terms - Page 17

<PAGE>

                                   EXHIBIT "B"
                         TO GAS STORAGE CONTRACT BETWEEN
                    HATTIESBURG INDUSTRIAL GAS SALES COMPANY
                       AND MISSISSIPPI VALLEY GAS COMPANY
                           EFFECTIVE FEBRUARY 21, 1990

<TABLE>
<CAPTION>
                                                                                    Maximum Quantity
                        POINT(S) OF DELIVERY                                          (In MMBtu's)
                        --------------------                                        ----------------
<S>                                                                                 <C>
Interconnection between the Storage                                                      10,000
Facilities and the pipeline facilities of Transco in Covington County,
Mississippi

Interconnection between the Storage                                                      10,000
Facilities and the pipeline facilities of Tennessee in Forrest County,
Mississippi
</TABLE>

Gas may be scheduled for delivery at either or both of the Points of Delivery,
in quantities up to the maximum quantities indicated for each such point, but
the cumulative total of deliveries at both Points of Delivery shall not exceed
the MDIQ stated in the Contract, unless otherwise agreed by Company.

<TABLE>
<CAPTION>
                                                                                    Maximum Quantity
                    POINT (S) Of REDELIVERY                                           (In MMBtu's)
                    -----------------------                                         ----------------
<S>                                                                                 <C>
Interconnection between the Storage                                                      20,000
Facilities and the pipeline facilities of Transco in Covington County,
Mississippi

Interconnection between the Storage                                                      20,000
Facilities and the pipeline facilities of Tennessee in Forrest County,
Mississippi
</TABLE>

Gas may be scheduled for delivery at either or both of the Points of Redelivery,
in quantities up to the maximum quantities indicated for each such point, but
the cumulative total of deliveries at both Points of Redelivery shall not exceed
the MDWQ stated in the Contract, unless otherwise agreed by Company.

<PAGE>

                                                                 HATTIESBURG - B

                         100,000 SUBSCRIBED IN PHASE 1


                                  FIRM STANDBY

                              GAS STORAGE CONTRACT

                                 BY AND BETWEEN

                    HATTIESBURG INDUSTRIAL GAS SALES COMPANY

                                      AND

                         MISSISSIPPI VALLEY GAS COMPANY

                                    EFFECTIVE

                                FEBRUARY 21, 1990

                                     PART B*

*        This Contract for 100,000 MQS ("Part B") is issued, together with a
         second contract for 200,000 MQS ("Part A"), in replacement of the
         original Firm Standby Gas Storage Contract for 300,000 MQS dated
         February 21, 1990.

<PAGE>

                                TABLE OF CONTENTS

                        FIRM STANDBY GAS STORAGE CONTRACT

<TABLE>
<S>                                                                               <C>
I.       ACQUISITION AND CONSTRUCTION...........................................   2
II.      GAS TO BE STORED AND DELIVERED.........................................   4
III.     SCHEDULING.............................................................   6
IV.      POINT(S) OF DELIVERY AND REDELIVERY....................................   8
V.       TERM ..................................................................   8
VI.      RATES .................................................................   9
VII.     NOTICES................................................................  13
VIII.    GENERAL TERMS AND CONDITIONS...........................................  15
IX.      ADDITIONAL STORAGE OPTION..............................................  15
X.       MISCELLANEOUS..........................................................  16

                                   Exhibit "A"
                          General Terms and Conditions

I.       DEFINITIONS............................................................   1
II.      QUALITY................................................................   3
III.     PRESSURE...............................................................   4
IV.      TITLE AND RISK OF LOSS.................................................   4
V.       MEASUREMENT............................................................   6
VI.      BILLINGS AND PAYMENTS .................................................   9
VII.     TAXES..................................................................  10
VIII.    REGULATORY BODIES......................................................  13
IX.      FORCE MAJEURE..........................................................  14
X.       DEFAULT AND TERMINATION................................................  16

                                   Exhibit "B"
                       Point(s) of Delivery and Redelivery
</TABLE>

<PAGE>

                              GAS STORAGE CONTRACT

         THIS GAS STORAGE CONTRACT (hereinafter referred to as the "Contract")
is made effective as of the 21st day of February, 1990, by and between
HATTIESBURG INDUSTRIAL GAS SALES COMPANY, a Delaware corporation, (f/k/a Endevco
Industrial Gas Sales Company) (herein referred to as "Company"), operator of the
Storage Facilities (as defined below) and managing general partner of the
Hattiesburg Gas Storage Company, the owner of the said Storage Facilities, and
MISSISSIPPI VALLEY GAS COMPANY, a Mississippi corporation (herein referred to as
"Customer").

                              W I T N E S S E T H:

         WHEREAS, Company and Customer are parties to a "Precedent Agreement"
dated October 13, 1989, wherein Company and Customer agreed, upon the
satisfaction of certain conditions, to enter into this Contract; and

         WHEREAS, the conditions in the Precedent Agreement have been satisfied
or waived; and

         WHEREAS, subject to the terms hereof, Company will acquire certain
caverns located near Petal, Mississippi and develop such caverns into
underground natural gas storage facilities (hereinafter referred to as the
"Storage Facilities") initially having a usable storage capacity of
approximately two billion cubic feet ("Phase I"), and which may, at Company's
discretion, subsequently be expanded to a capacity of approximately five billion
cubic feet of usable storage capacity ("Phase II"); and

<PAGE>

         WHEREAS, Company will install and construct all facilities necessary to
connect the Storage Facilities with the Point(s) of Delivery and Point(s) of
Redelivery herein specified; and

         WHEREAS, Customer desires that Company receive, on a firm basis, at the
Points of Delivery herein specified, certain quantities of gas from the pipeline
facilities of Transcontinental Gas Pipe Line Corporation ("Transco") and/or
Tennessee Gas Pipeline Company ("Tennessee") for the purpose of injecting and
storing such gas for Customer or for its account in such Storage Facilities, and
that Company redeliver such gas, on a firm basis, into the facilities of said
pipeline companies, at the Points of Redelivery herein specified; and

         WHEREAS, Company desires to perform such services for Customer, all to
be provided pursuant and subject to the terms and conditions hereof;

         NOW, THEREFORE, for and in consideration of the mutual covenants herein
contained, together with other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged and confessed by both parties
hereto, Company and Customer hereby agree as follows:

                                    ARTICLE I

                          ACQUISITION AND CONSTRUCTION

         Within thirty (30) days after the execution hereof, Company shall
endeavor to close its purchase of the Storage Facilities, on terms and
conditions satisfactory to Company. Thereafter, Company shall commence the
construction and development of the Storage Facilities and shall provide
Customer written notice of the

                                       2

<PAGE>

commencement of construction and the date upon which Company anticipates that
such facilities will be operational. Upon completion of construction, including
testing, as required by all applicable federal, state and/or applicable codes,
and all other matters required for operation, Company shall provide Customer
written notice that said facilities are fully operational and shall state in
such notice a date upon which Company will be ready to receive gas for storage,
which date shall be not less than thirty (30) days following such notice (such
date to be hereinafter referred to as the "Commencement Date"). If the
Commencement Date does not occur on or before December 1, 1990, or such later
date as may be agreed upon, (subject to a day for day extension for delays
caused by an event(s) of "force majeure" as herein defined and for each day
after March 8, 1990 which expires prior to the date that Company receives
executed Firm Storage Contracts covering at least 165,000 MMBtu of MDWQ, as
herein defined), for any reason, including, without limitation, Company's
inability to close its purchase of the Storage Facilities on terms acceptable to
Company, then either party shall have the right to terminate this Contract,
without further liability or obligation to the other party hereunder, by
providing the other party thirty (30) days prior written notice. Notwithstanding
the foregoing, in the event that Customer gives notice of termination in
accordance with the above and, thereafter, Company provides written notice to
Customer stating a Commencement Date which will occur prior to the expiration of
such thirty (30) day period, then, Customer's notice of termination shall be
void and of no further force or effect and

                                       3

<PAGE>

this Contract shall continue in accordance with its terms, unless Company is
unable to commence service on the Commencement Date stated in its notice.

                                   ARTICLE II

                         GAS TO BE STORED AND DELIVERED

         2.1      Subject to the terms and provisions of this Contract, Company
agrees to reserve for service to Customer a portion of the Storage Facilities.
The capacities so reserved for Customer shall be sufficient to enable Customer
to inject gas into, withdraw gas from, and store gas in the Storage Facilities,
in quantities up to the maximum quantities set forth below:

         (i)      a maximum daily withdrawal quantity ("MDWQ") of 10,000 MMBtu
                  per day;

         (ii)     a maximum daily injection quantity ("MDIQ") of 5,000 MMBtu per
                  day;

         (iii)    a maximum capacity in the Storage Facilities ("MQS") equal to
                  100,000 MMBtu.

         2.2      Customer shall tender or cause to be tendered to Company at
the Point(s) of Delivery any gas which Customer desires to have injected into
storage hereunder. Customer shall also receive or cause to be received gas
requested to be withdrawn from storage at the Point(s) of Redelivery upon tender
for redelivery by Company.

         2.3      Subject to the operating conditions of the pipelines
delivering or receiving gas for Customer's account, Company shall receive gas
for injection from Customer at the Point(s) of Delivery and redeliver gas to
Customer at the Point(s) of Redelivery as scheduled by Customer from time to
time; provided that Company

                                       4

<PAGE>

shall not be obligated to receive for injection any quantity of gas if the
injection of the same would cause the quantity of gas stored in the Storage
Facilities for Customer's account ("Customer's Gas Storage Inventory") to exceed
Customer's MQS as stated above; nor shall Company be obligated at any time to
deliver more gas to Customer than Customer has in its then-current Customer's
Gas Storage Inventory.

         2.4      Company shall not be obligated to receive, at any Point of
Delivery for injection, or to redeliver, at any Point of Redelivery, any
quantity of gas when the quantity of gas tendered for delivery to Company or
requested by Customer to be redelivered, together with all other volumes of gas
tendered for delivery to Company at any such Point of Delivery, or requested for
redelivery at such Point of Redelivery, is less than 5,000 MMBtu per day in the
aggregate.

         2.5      In addition to the maximum daily rates of injection and
withdrawal as specified above in Section 2.1, Company shall use its best efforts
to accommodate requests of Customer to inject or withdraw gas at greater rates
of flow and, at such Point(s) of Delivery or Point(s) or Redelivery in addition
to those specified on Exhibit "B" annexed hereto, at such times as such
additional capacities are not required for service to other firm, standby
storage customers. Any such additional services shall be provided at the rates
stated in Section 6.1(c) and 6.1(d), as may be amended by Section 6.1(e), only
as capacities are available and on a pro-rata basis to other firm, standby
storage customers, without obligation or liability for interruption by Company
as to any

                                       5

<PAGE>

withdrawals or injections in excess of the maximums reserved for Customer.
Additional withdrawals and/or injections will be made only to the extent that
Customer has gas in storage to be withdrawn, or unfilled capacity in the Storage
Facilities reserved as part of Customer's MQS as stated herein.

                                   ARTICLE III

                                   SCHEDULING

         3.1      At any time during any day when Customer desires Company to
receive and inject gas into, or to withdraw and deliver gas from, the Storage
Facilities, Customer shall give verbal notice in accordance with Section 3.2 of
this Article to Company's dispatcher, specifying the quantity of gas to be
injected or withdrawn and the appropriate Points of Delivery or Points of
Redelivery, as applicable. Customer shall make available and tender any gas to
be injected hereunder and receive and accept delivery, upon tender by Company,
any gas requested to be withdrawn from storage. The quantity of gas stored in
the Storage Facilities for the account of Customer shall be increased or
decreased upon injection or withdrawal of gas from storage, as applicable.
Customer shall not (unless otherwise agreed by Company), on an hourly basis,
tender for injection nor shall Company be obligated to receive gas for injection
or to withdraw and deliver gas from storage, at rates of flow in excess of 1/24
of Customer's MDIQ or MDWQ, respectively.

         3.2      Customer shall notify Company at least eight (8) hours in
advance of any requested change in the daily or hourly rate of flow for
injections or withdrawals of gas hereunder. Company may waive

                                       6

<PAGE>

any part of the eight (8) hour notice upon request if, in Company's reasonable
judgement, operating conditions permit such waiver. Customer shall notify
Company immediately of any circumstance which causes or will cause the
deliveries to or receipts from Company to be different from those requested.
Notices provided in this Article may be verbal, followed by a written
confirmation delivered via telecopy, overnight mail, first class U.S. mail, or
hand-delivery when such written confirmation is requested by either party.
Customer shall provide notice of any changes in deliveries to or receipts from
Company to all applicable transporting pipelines and shall be responsible for,
and shall indemnify and hold Company harmless from, any and all liabilities and
expenses resulting from Customer's failure to notify all applicable transporting
pipelines of any such changes.

         3.3      In the event that an imbalance occurs on the pipeline to or
from which such gas is delivered or received, which imbalance results from
Company's failure to tender the quantities of gas scheduled for delivery from
storage, or accept delivery of the quantities of gas scheduled for injection
into storage and tendered for delivery by Customer, all in accordance with and
subject to this Contract, Company shall reimburse Customer for any imbalance
penalty due and rightfully owing to the pipeline receiving or delivering the gas
at such Point(s) of Delivery or Point(s) of Redelivery, which was caused by
Company's failure to accept or deliver gas. In the event that Company is unable
to receive or deliver gas as required by this Contract and in accordance with
the request of Customer as provided above, Company shall notify

                                       7

<PAGE>

Customer as soon as practicable following any failure to receive or tender such
gas and, Customer shall, as soon as practicable following receipt of such
notice, notify and change nominations and scheduling with all pipelines and
other parties delivering or receiving gas to be delivered to or withdrawn from
storage for Customer and be reasonably diligent in taking such further actions
to prevent or minimize any imbalances from occurring. Customer and Company will
diligently work to correct any imbalance so caused prior to the end of the
applicable balancing period.

                                   ARTICLE IV

                       POINT(S) OF DELIVERY AND REDELIVERY

         4.1      The Point(s) of Delivery for all gas to be tendered by
Customer to Company for injection into the Storage Facilities shall be as
specified on Exhibit "B" attached hereto, and the maximum daily quantity of gas
which Company is obligated to receive from Customer at each individual Point of
Delivery shall not exceed the maximum stated thereon.

         4.2      The Point(s) of Redelivery for all gas to be tendered by
Company to Customer for redelivery pursuant to the terms hereof shall be as
specified on Exhibit "B", attached hereto, and the maximum quantities of gas
which Company is obligated to redeliver to Customer at each such Point of
Redelivery shall not exceed the maximum stated thereon.

                                    ARTICLE V

                                      TERM

         5.1      This Contract shall be effective as of the date set forth at
the outset hereof and shall continue in full force and effect

                                       8

<PAGE>

for a primary term of fifteen (15) years following the Commencement Date, as
defined in Article I hereof, and year to year thereafter unless and until
terminated effective at the end of such fifteenth (15th) year or any year
thereafter by either party upon not less than thirty-six (36) months prior
written notice.

         5.2      Upon expiration hereof, Company agrees that in the event that
gas storage services are still being provided in the Storage Facilities by
Company, or any assignee of Company as provided for herein, to other customers,
then, Customer shall have the right and option to continue to receive storage
services from Company, or such assignee of Company, pursuant to terms and
conditions, and for rates and charges substantially similar to those being
offered to said other customers by Company, or such assignee of Company, at the
time of such expiration.

                                   ARTICLE VI

                                      RATES

         6.1      During the first ten (10) years following the Commencement
Date, Customer shall pay to Company each month the following charges:


                  6.1(a)   A storage charge ("D (1)") of twenty and one-half
         cents ($0.205) multiplied by Customer's MQS amount specified in this
         Agreement; plus


                  6.1(b)   A deliverability charge ("D (2)") of fifty-eight
         cents ($0.58) multiplied by Customer's MDWQ amount; plus


                  6.1(c)   One cent ($0.01) for each MMBtu of gas received by
         Company for injection into storage hereunder and one cent

                                       9

<PAGE>

         ($0.01) for each MMBtu of gas redelivered by Company to Customer
         hereunder; plus

                  6.1(d)   Customer's pro-rata share of the cost of gas consumed
         in the operation of the Storage Facilities, such to be pro rated among
         all Customers based upon the quantities of gas injected and withdrawn
         by each Customer during each month. It is presently estimated that the
         total cost of gas to be consumed in the injection and withdrawal of gas
         into and from the Storage Facilities will initially total approximately
         three cents ($0.03) per MMBtu, in the aggregate; however, the parties
         agree that this cost may change from time to time and Customer shall
         continue to bear its pro rata share of such cost. Company shall
         endeavor to operate the Storage Facilities in an efficient manner so as
         to limit the gas consumed to that quantity reasonably required. Each
         month, Company shall provide Customer a statement showing its prorata
         share of such quantity and the cost of the gas consumed in the
         operation of Storage Facilities, along with the necessary supporting
         workpapers showing the total quantity and cost of gas so consumed and
         the proration calculations. Customer shall have the option, exercisable
         upon thirty (30) days prior written notice at any time during the term
         hereof, to thereafter (during the term hereof) supply its pro-rata
         share of gas consumed, as opposed to reimbursing Company in accordance
         herewith. In the event that Customer elects to provide its pro-rata
         share of the fuel used hereunder, then, following such election,
         Company shall establish and maintain

                                       10
<PAGE>

an account (the "Fuel Account") with Customer. Initially, one and one-half
percent (1 1/2%) of all gas delivered to Company at the Points of Delivery
hereunder shall be retained by Company and credited to the Fuel Account.
Customer shall not pay any injection, withdrawal or storage fee as to any
volumes retained by Company. At the close of each month, Company shall debit the
Fuel Account with Customer's pro-rata share of the fuel gas. From time to time
during the term hereof, Company shall have the right, upon providing Customer
ten (10) days' prior written notice, to adjust the quantity of gas to be
retained by Company and credited to the Fuel Account in order to reflect actual
quantities of gas consumed in the operation of the Storage Facilities and, to
cause the Fuel Account to be as near to zero as is practicable on a monthly
basis. Within thirty (30) days following the termination hereof, Company shall
deliver gas to Customer, or Customer shall deliver gas to Company, as is
necessary to cause the Fuel Account to equal zero. Company shall report the
status of the Fuel Account as of the end of the previous month with each monthly
statement. Customer shall have the right to deliver to Company the maximum
capacities set forth in Section 2.1(iii) in addition to the gas delivered by
Customer for credit to the Fuel Account.

         6.1(e)   The fees payable for each MMBtu of gas delivered to Company
for injection and for each MMBtu of gas redelivered to Customer hereunder, as
provided for in section 6.1(c), shall be subject to adjustment, upon

                                       11

<PAGE>

         application to and approval by the appropriate regulatory commission,
         to reflect increases or decreases in the cost of maintenance, supplies
         and other variable expenses incurred by Company in performing the
         services hereunder. Customer shall have the right to contest any
         increase sought hereunder before the appropriate regulatory commission.
         No such adjusted fee shall exceed, however: (i) the fee herein
         provided; multiplied by (ii) the sum of one (1) plus the percentage
         change in the Gross National Product Implicit Price Deflator (the
         "Index") for the December of the then-current calendar year as compared
         to such Index for December, 1990.

         6.2      Notwithstanding the above, in the event that Company elects to
expand the Storage Facilities as referenced in section 9.1, the rates and
charges payable hereunder during the remaining portion of the initial ten (10)
years hereof shall be redetermined such that the sum of: (a) the D(1) storage
charge, as provided in section 6.1(a); and (b) the D(2) deliverability charge,
as provided in section 6.1(b); will be reduced such that the total reservation
charges payable hereunder during each month shall not exceed eighty percent
(80%) of the total reservation charges payable hereunder prior to such expansion
and rate redetermination.

         6.3      The charges payable hereunder for the remainder of the term
hereof following the tenth (10th) year (after the Commencement Date) may be
redetermined by the appropriate regulatory body in accordance with this section
6.3. Company shall have the right, upon its election, or shall be obligated,
upon request of Customer, to submit cost-of-service information to the
appropriate regulatory

                                       12

<PAGE>

authority for a review of the rates charged hereunder and to request a
determination by such regulatory authority of a rate for the remaining term
hereof. Customer shall have the right to take part in such proceedings and to
contest the proposed rates to the full extent allowed. Company shall provide
Customer not less than thirty (30) days prior written notice of Company's intent
to file for a new rate as herein provided. In the event that the rates resulting
from such redetermination are in excess of one hundred and ten percent (110%) of
the rates specified in Section 6.1, then Customer shall have the right to
terminate this Contract upon sixty (60) days' prior written notice; provided,
however, that during such sixty (60) day period following the receipt of
Customer's notice, Company shall have the option, without obligation, to agree
to charge Customer rates which do not exceed one hundred and ten percent (110%)
of the rates set forth in Section 6.1 and, in such event, this Contract shall
continue for the remaining term. Company shall provide Customer written notice
of any such election before the expiration of said sixty (60) day period and,
shall therein specify the rate to be charged hereunder.

                                   ARTICLE VII

                                     NOTICES

         7.1      Whenever any notice, request, demand, statement or payment is
required or permitted to be given under any provision of this Contract, unless
expressly provided otherwise, such shall be in writing, signed by or on behalf
of the person giving the same, and shall be deemed to have been given and
received upon the

                                       13

<PAGE>

actual receipt (including the receipt of a telecopy or facsimile of such notice)
at the address of the parties as follows:

         Company:

         For Notices:       Hattiesburg Industrial Gas Sales Company
                            5950 Berkshire Lane
                            Suite 1400, L.B. 17
                            Dallas, Texas 75225

         Payments
         (Wire Transfer) :  Union Bank of California -- Los Angeles
                            ABA # 122000496
                            For Account of Hattiesburg Gas Storage Company
                            Acct No. 0880411845

         Customer:          Mississippi Valley Gas Company
                            711 W. Capital Street
                            Jackson, Mississippi 39203

         7.2      Operating communications made by telephone or other mutually
agreeable means shall be confirmed in writing or by telecopy within two (2) days
following same if requested by either party. To facilitate such operating
communications on a daily basis, lists of names, telephone and telecopy numbers
of appropriate operating personnel shall be exchanged by and between Company and
Customer before commencement of service under this Contract. Such lists shall be
updated from time to time if changed.

         7.3      The addresses of the parties may be revised upon written
notice given in accordance herewith, designating in such writing the new address
of the party so affected.

                                       14

<PAGE>

                                  ARTICLE VIII

                          GENERAL TERMS AND CONDITIONS

         The General Terms and Conditions attached hereto as Exhibit "A" are
hereby incorporated herein and made a part of this Contract as if fully set
forth herein. Any conflict or inconsistency, either in construction or
interpretation, between the terms hereof and the General Terms and Conditions
attached hereto shall be resolved in favor of the terms hereof,

                                   ARTICLE IX

                           ADDITIONAL STORAGE OPTION

         9.1      Company anticipates that it may elect to expand the Storage
Facilities at some time following initial storage operations. In the event that
Company so elects to expand the Storage Facilities, Company hereby grants
Customer an option on a pro rata portion of any increased capacities (for
storage, withdrawal or injection) developed by Company in the Storage
Facilities. Such proportionate share shall equal (i) the total additional
capacity (for storage, withdrawal or injection) developed by Company in such
Storage Facilities multiplied by (ii) a fraction, the numerator of which shall
equal Customer's rights to such capacity hereunder (MQS, MDWQ or MDIQ) and the
denominator of which shall equal the total storage capacity (for storage,
withdrawal or injection) of the Storage Facilities immediately preceding such
increase in capacity. Customer shall exercise its option, if at all, in
accordance with section 9.2 below.

                                       15

<PAGE>

         9.2      In the event that Company makes the determination to increase
any capacity (for storage, withdrawal or injection) at the Storage Facilities,
Company shall so notify Customer in writing. Such notice shall contain the terms
and conditions upon which Company will contract with other parties for such
capacity(ies), which terms shall be similar to those provided in this Contract.
For ninety (90) days following receipt of such notice, Customer shall have the
right, without obligation, to contract for additional storage rights in the
Storage Facilities upon the terms and conditions offered by Company and
reflected in the notice or such other terms as may be agreed to by Customer and
Company. Should Customer elect to contract for such additional rights, and
provide Company with written notice of such election within such ninety (90) day
period, Company shall provide Customer with formal contracts for execution. The
failure of Customer to provide written notice to Company of its election to
contract for such additional capacity rights within such ninety (90) day period,
or the failure of Customer, following such election, to execute and return to
Company the contract provided to Customer within thirty (30) days following
Customer's receipt of same, shall be deemed a waiver of Customer's option on
such capacity(ies).

                                   ARTICLE X

                                 MISCELLANEOUS

         10.1     Headings. The subject headings of the articles and sections of
this Contract are intended for the sole purpose of convenient reference and are
not intended, nor shall the same be

                                       16

<PAGE>

construed, to be a part of this Contract or considered in any interpretation
hereof.

         10.2     Amendment. Neither this Contract nor any provisions hereof may
ever be amended, changed, modified or supplemented except by an agreement in
writing, duly executed by the party to be charged with the same.

         10.3     Waiver. No failure by either party to enforce the performance
of any obligation of the other party under this Contract shall operate as a
waiver of such obligation or default, or as a waiver of any other right or
default, whether of a like or different character.

         10.4     Choice of Law. As to all matters of construction and
interpretation, this Contract shall be interpreted, construed and governed by
the laws of the State of Texas.

         10.5     Succession. Either party may assign its rights, titles or
interests hereunder to any individual, bank, trustee, company or corporation as
security for any note, notes, bonds or other obligations or securities of such
assignor, but not otherwise, without the written consent of the other party
hereto, which consent shall not be unreasonably withheld. No assignment provided
for hereunder shall in any way operate to enlarge, alter or change any
obligation of the other party hereto nor shall the assignee be relieved of its
obligations hereunder without the express written consent of the non-assigning
party.

         10.6     Right of Examination. Both Company and Customer shall have the
right to examine, at any reasonable time, the books, records, charts and any
operating data of the other to the extent

                                       17

<PAGE>

reasonably necessary to verify the accuracy of any statement, chart or
computation made under or pursuant to the provisions of this Contract. All
books, records and charts related to any statement, charge or computation made
hereunder shall be retained and available for review or inspection for a period
of two years.

         10.7     Entire Agreement. This Contract contains the entire agreement
and understanding of the parties hereto and there are no agreements,
understandings or representations, either oral or in writing, except as set
forth herein. That certain Precedent Agreement, between Customer and Company, is
hereby expressly superseded and terminated by the execution hereof.

         10.8     Authority. Company and Customer each hereby represents and
warrants that it has the full right, power and authority to enter into this
Contract, and that this Contract will not violate the provisions of any other
contract or agreement to which it is a party.

         10.9     Reissuance of Original Contract. This Contract ("Part B"), and
another Gas Storage Contract of even date herewith specifying a MQS of 200,000
("Part A"), are issued in replacement of that certain Firm Standby Gas Storage
Contract between Customer and Company dated February 21, 1990. The replacement
of the former contract is effected for administrative purposes only, and shall
be interpreted and construed for all purposes as merely a continuation of the
original contract.

         IN WITNESS WHEREOF, the parties have executed this Contract in one or
more copies or counterparts, each of which shall constitute

                                       18

<PAGE>

and be an original of this Contract effective between the parties effective as
of the date first-above written.

                                        COMPANY:

ATTEST:                                 HATTIESBURG INDUSTRIAL GAS SALES COMPANY

[ILLEGIBLE]                             By: [ILLEGIBLE]
---------------------------------           ------------------------------------
                                        Its: President

                                        CUSTOMER:

ATTEST:                                 MISSISSIPPI VALLEY GAS COMPANY

[ILLEGIBLE]                             By: -s- Warren K. Rogers
---------------------------------           ------------------------------------
                                        Its: Senior Vice President

                                       19

<PAGE>

                                   EXHIBIT "A"

                         TO GAS STORAGE CONTRACT BETWEEN
                    HATTIESBURG INDUSTRIAL GAS SALES COMPANY
                       AND MISSISSIPPI VALLEY GAS COMPANY
                          EFFECTIVE FEBRUARY 21, 1990

                          GENERAL TERMS AND CONDITIONS

         These General Terms and Conditions ("General Terms") are attached to
and incorporated into the above-referenced GAS STORAGE CONTRACT between
HATTIESBURG INDUSTRIAL GAS SALES COMPANY (herein referred to as "Company") and
MISSISSIPPI VALLEY GAS COMPANY, a Mississippi corporation (herein referred to as
"Customer").

                                    ARTICLE I

                                   DEFINITIONS

         For the purposes of this Contract, unless expressly stated otherwise,
the following definitions shall be applicable.

         1.1      The term "Btu" shall mean British Thermal Units.

         1.2      A "day" shall mean the twenty-four (24) hour period beginning
at 7:00 a.m. Jackson, Mississippi time on each calendar day and ending at 7:00
a.m. Jackson, Mississippi time on the following calendar day.

         1.3      "Contract" shall mean the above-referenced Gas Storage
Contract together with these General Terms and all other attachments hereto or
thereto.

         1.4      The term "gas" shall mean natural gas in its natural state,
produced from wells, including casinghead gas produced with crude oil, natural
gas from gas wells and residue gas resulting from processing both casinghead gas
and gas well gas.

General Terms - Page 1

<PAGE>

         1.5      The term "Mcf" shall mean one thousand (1,000) cubic feet at a
pressure of fifteen and twenty-five thousandths (15.025) psia and at a
temperature of sixty degrees (60 degrees) Fahrenheit.

         1.6      The term "MMBtu" shall mean 1,000,000 Btu.

         1.7      A "month" shall mean that period of time beginning at 7:00
a.m. Jackson, Mississippi time on the first day of a calendar month and ending
at 7:00 a.m. Jackson, Mississippi time on the first day of the following
calendar month; provided, that, the first month hereunder shall commence on the
first day of the calendar month in which the Commencement Date occurs, and the
last month hereunder shall end on the date that this Contract terminates.

         1.8      "Point(s) of Delivery" shall mean the point or points, as
identified on Exhibit "B" of the Contract, at which gas is received by Company
for injection into storage.

         1.9      "Point(s) of Redelivery" shall mean the point or points, as
identified on Exhibit "B" of the Contract, at which gas is tendered by Company
to Customer for delivery from storage.

         1.10     The term "psia" shall mean pounds per square inch absolute.

         1.11     The term "psig" shall mean pounds per square inch gauge.

         1.12     "Storage Facilities" shall be as defined in the "WHEREAS"
clauses of the Contract.

         1.13     The term "year" shall mean a period of twelve (12) consecutive
months.

General Terms - Page 2

<PAGE>

                                   ARTICLE II

                                     QUALITY

         The gas delivered by either party to the other hereunder shall meet the
quality specifications of the transporting pipeline which receives or delivers
such gas at the Point(s) of Delivery or Redelivery and shall, in addition, be
of such quality that it shall meet the following specifications, if such
standards are more stringent:

         a.       Be commercially free of dust, gum, gum-forming constituents,
                  gasoline, and other solid and/or liquid matter, including but
                  not limited to water, gas treating chemicals and well
                  completion fluids and debris, which may become separated from
                  the gas during transportation thereof.

         b.       Contain not more than one quarter (1/4) grain of hydrogen
                  sulphide per one hundred (100) cubic feet, as determined by
                  the cadmium sulfate quantitative test, nor more than nine (9)
                  grains of total sulfur per one hundred (100) cubic feet.

         c.       The gas delivered hereunder shall not contain more than
                  two-tenths of one percent (0.2%) by volume of oxygen, and
                  shall not contain more than two percent (2%) by volume of
                  carbon dioxide; and shall not contain more than two percent
                  (2%) by volume of nitrogen.

         d.       Have a heating value of not less than nine hundred eighty
                  (980) Btu's per cubic feet.

General Terms - Page 3

<PAGE>

         e.       Have a temperature of not more than one hundred twenty degrees
                  Fahrenheit (120 degrees F), nor less than forty degrees
                  Fahrenheit (40 degrees F).

         f.       Have been dehydrated by any method other than the use of a
                  calcium chloride as desiccant, for removal of entrained water
                  in excess of seven (7) pounds of water per million (1,000,000)
                  cubic feet of gas.

                                   ARTICLE III

                                    PRESSURE

         Company shall deliver gas to Customer from storage hereunder at
pressures sufficient to enter the transporting pipeline's facilities at the
Point(s) of Redelivery against the operating pressures maintained in such
pipeline from time to time, provided that Company shall not be required to
deliver gas at pressures in excess of 960 psig. Customer shall deliver gas to
Company for injection at the Point(s) of Delivery at the pressures as may be
available from time to time in the transporting pipeline's facilities at such
points, but in no event shall such pressures be less than 550 psig or greater
than Company's maximum allowable operating pressure.

                                   ARTICLE IV

                             TITLE AND RISK OF LOSS

         4.1      Title to the natural gas stored by Company and delivered to
Customer hereunder shall, at all times, be in Customer and, except as provided
in Section 4.2 Company makes no warranty of title whatsoever. Customer warrants
for itself, its successors and

General Terms - Page 4

<PAGE>

assigns, that it will have at the time of delivery of gas storage hereunder good
title or valid right to deliver such stored hereunder. Customer warrants for
itself, its successors and assigns, that the gas it delivers hereunder shall be
free and clear of all liens, encumbrances, or claims whatsoever; and that it
shall indemnify Company and save it harmless from all claims, actions, damages,
costs and expenses arising directly or indirectly from or with respect to the
title to gas tendered to Company hereunder.

         4.2      Company warrants that it shall neither cause nor allow any
cloud or encumbrance of any nature to arise by, through or under Company with
respect to Customer's title to any gas tendered to Company for storage, and
agrees to redeliver such gas pursuant to this Contract free from all liens and
adverse claims arising by, through or under Company, and that it will indemnify,
defend, protect, and save Customer harmless from all claims, suits, actions,
damages, costs and expenses arising directly or indirectly from the same.

         4.3      As between Customer and Company: Customer shall be in control
and possession of the gas prior to delivery to Company for injection at the
Point(s) of Delivery and after redelivery by Company to Customer at the Point(s)
of Redelivery, and, shall indemnify, defend and hold Company harmless from any
damage or injury caused thereby except for damages and injuries caused by the
negligence of Company; and, Company shall be in control and possession of the
gas after the receipt of the same for injection at the Point(s) of Delivery and
until redelivery by Company to

General Terms - Page 5

<PAGE>

Customer at the Point(s) of Redelivery, and, shall indemnify, defend and hold
Customer harmless from any damage or injury caused thereby, except for damages
and injuries caused by the negligence of Customer. The risk of loss for all gas
injected into, stored in and withdrawn from the Storage Facilities shall be and
remain with the party having control and possession of the gas as herein
provided.

                                    ARTICLE V

                                   MEASUREMENT

         5.1      The unit of volume for measurement of gas delivered hereunder
shall be one (1) cubic foot of gas at a base temperature of sixty degrees
Fahrenheit (60 degrees F) and at an absolute pressure of fifteen and twenty-five
thousandths (15.025) pounds per square inch. All fundamental constants,
observations, records, and procedures involved in determining and/or verifying
the quantity and other characteristics of gas delivered hereunder shall, unless
otherwise specified herein, be in accordance with the standards prescribed in
American Gas Association ("A.G.A.") Gas Measurement Committee Report No. 3, as
now and from time to time amended or supplemented. All measurements of gas shall
be determined by calculation into terms of such unit. All quantities given
herein, unless expressly stated otherwise, are in terms of such unit.
Notwithstanding the foregoing, it is agreed that, for all purposes, the Btu
content of the gas received and delivered by Company hereunder shall be measured
on an "as delivered" basis rather than a fully saturated or "wet" basis.

General Terms - Page 6

<PAGE>

         5.2      Company, at its sole expense, shall install, maintain and
operate, or cause to be installed, maintained and operated, the measurement
facilities required hereunder. Said measurement facilities shall be so equipped
with orifice meters, recording gauges, or other types of meters of standard make
and design commonly acceptable in the industry, as to accomplish the accurate
measurement of gas delivered hereunder. The changing of charts, calibrating and
adjustment of meters shall be done by Company or its agent.

         5.3      The accuracy of Company's measuring equipment shall be
verified by Company at least once in each thirty (30) day period. If either
party desires a special test of any measuring equipment, it will promptly notify
the other party and the parties shall then cooperate to secure a prompt
verification of the accuracy of such equipment. The expenses of any such special
test, if requested by Customer, shall be borne by Customer if the measuring
equipment tested is found to be accurate within the limit of plus or minus two
percent (2%) of error. For the purposes of measurement and meter calibration,
the atmospheric pressure shall be assumed to be fourteen and seventy-three
hundredths (14.73) pounds per square inch, irrespective of variations in natural
atmospheric pressure from time to time. Company and Customer, upon request,
shall have the right to be present at any test of any measuring equipment,
including any check measuring equipment installed by Customer at its sole
expense.

General Terms - Page 7

<PAGE>

         5.4      If upon testing, the metering equipment is found to be
inaccurate, in the aggregate, by two percent (2%) or more, either plus or minus,
registration thereof and any payment based upon such registration shall be
corrected at the rate of such inaccuracy for any period of inaccuracy which is
definitely known or agreed upon, or if not known or agreed upon, then for a
period extending back one-half (1/2) of the time elapsed since the day of the
last calibration, not exceeding, however, forty-five (45) days. Following any
test, any metering equipment found to be inaccurate to any degree shall be
adjusted immediately to measure accurately; however, if any inaccuracy is less
than two percent (2%), all prior readings and measurements shall be deemed to
be accurate and no adjustments to any prior reading shall be made. If, for any
reason, any meter is registering inaccurately or is out of service or out of
repair so that the quantity of gas delivered through such meter cannot be
ascertained or computed from the readings thereof, the quantity of gas so
delivered during such period shall be estimated and agreed upon by the parties
hereto upon the basis of the best available data determined,

         a.       by using the registration of any check measuring equipment, if
                  installed and registering accurately or in the absence of (a);

         b.       by correcting the error if the percentage of error is
                  ascertainable by calibration, test, or mathematical
                  calculation, or in the absence of both (a) and (b);

General Terms - Page 8

<PAGE>

         c.       by estimating the quantity of gas deliveries by deliveries
                  during preceding periods under similar conditions when the
                  meter was registering accurately.

         5.5      The measurement hereunder shall be corrected for deviation
from Boyle's Law at the pressure and temperature under which gas is delivered
hereunder.

                                   ARTICLE VI

                             BILLINGS AND PAYMENTS

         6.1      On or before the first (1st) day of each month, Company shall
render to Customer an invoice for the storage charge (D(1)) and the
deliverability charge (D(2)) due hereunder for such month. Customer shall pay
such invoiced amounts on or before the fifteenth (15th) day of the month for
which such charges are due.

         6.2      On the tenth (10th) day of each month, Company shall render to
Customer a statement for the preceding month properly identifying the applicable
Point(s) of Delivery and Point(s) of Redelivery and showing the total quantity
of gas received from and delivered to Customer hereunder, the amounts due
pursuant to Sections 6.1(c) and 6.1(d) of the Gas Storage Contract therefor, the
amount of Customer's gas in storage as of the close of such month, and
information sufficient to explain and support any adjustments made by Company
(in accordance with section 6.4 below) in determining the amount billed.
Customer shall pay Company the full amount reflected on the statements rendered
within fifteen (15) days of its receipt of same. If the fifteenth (15th) day
shall fall upon a weekend or legal holiday, then such payment shall

General Terms - Page 9

<PAGE>

be made on the first regular business day following such fifteenth (15th) day.

         6.3      In the event that Customer fails to pay any amounts when due,
interest shall accrue on all unpaid amounts from the date due until paid at a
rate of interest equal to the lesser of: (i) the rate of interest quoted as the
"prime rate" of NCNB Texas National Bank -- Dallas, Texas to its largest and
most credit-worthy commercial customers; or (ii) the highest legal rate of
interest allowed by law.

         6.4      In the event an error is discovered in the amount billed in
any statement rendered by Company, such error shall be adjusted within thirty
(30) days of the discovery of the error. In the event a dispute arises as to the
amount payable in any statement rendered, Customer shall pay the amount shown
payable to Company in the statement which is not in dispute. Any overcharges
collected by Company pursuant to this section 6.4 shall be remitted to Customer,
with interest, calculated as provided in section 6.3, from the date such
overcharges are received by Company until repaid. Such payment shall not be
deemed to be a waiver of the right by Customer to recoup any overpayment. All
statements shall be considered final, and any and all objections thereto be
deemed waived, unless made in writing within twenty-four (24) months of
Customer's receipt thereof.

General Terms - Page 10

<PAGE>

                                   ARTICLE VII

                                      TAXES

         7.1      Subject to the provisions of Section 7.3, Customer agrees to
pay to Company, by way of reimbursement, within fifteen (15) days of receipt of
an invoice for same (pro-rated among all customers), all new taxes enacted and
levied or imposed upon Company after the Commencement Date and, any increases in
existing taxes which may be made effective after the Commencement Date, which
arise out of the gas storage services provided hereunder. In the event that any
additional taxes or increases in taxes are imposed with respect to the storage
of gas hereunder and, should Company elect not to challenge the same, then
Customer shall be subrogated to Company's rights to challenge same.

         7.2      The term "taxes" as used herein, shall mean all taxes which
are now in existence or which may in the future be levied upon Company, or its
facilities or the storage of gas hereunder and arising out of the gas storage
services to be provided hereunder including, but not limited to, street and
alley rental tax, licenses, fees and any other taxes, charges or fees of any
kind levied, assessed or made by any governmental authority on the act, right or
privilege of transporting, handling or delivering gas or using Company's Storage
Facilities, which is measured by the volume, heating value, value of the gas, or
any fee in respect to the gas or the storage, transportation or other handling
thereof (excluding, however, real property, ad valorem, capital stock, income or
excess profit taxes, or general franchise taxes imposed

General Terms - Page 11

<PAGE>

on corporations on account of their corporate existence or on their right to do
business within the state as a foreign corporation and similar taxes).

         7.3      Customer shall not be obligated to reimburse Company pursuant
to Section 7.1 in any year in an amount in excess of five percent (5%) of the
cumulative total of the monthly demand charges paid by Customer to Company in
such year. In the event that the total of the increases in taxes and additional
taxes exceed such five percent (5%) amount, then Company shall have the option
of paying the same or of seeking a determination from the appropriate regulatory
agency that such additional taxes or increases in taxes are prudent and
appropriate for inclusion in Company's rates. Subject to the following
provisions, in the event that such regulatory agency determines that such
additional and increased taxes including, without limitation, those in excess of
said five percent (5%) amount, are appropriate for inclusion, Customer shall
have the option of either paying such approved rate increases or terminating
this Contract, upon providing Company sixty days' prior written notice;
provided, however, that upon receipt of Customer's notice of termination,
Company shall have the option, without obligation, to charge Customer an
increased amount which does not exceed such five percent (5%) amount and, in
such event, Customer's notice of termination shall be of no force or effect and
this Contract shall continue in accordance with its terms. Company shall provide
Customer written notice of any such election within such sixty (60) day period.
Customer shall be given notice and

General Terms - Page 12
<PAGE>

shall have the right to participate in such rate determination and oppose the
appropriateness of including the additional or increased taxes in Company's
rates.

                                  ARTICLE VIII

                               REGULATORY BODIES

         This Contract is subject to all present and future valid laws and
lawful orders of all regulatory bodies now or hereafter having jurisdiction of
either or both the parties; and should either of the parties, by force of any
such law or regulation imposed at any time during the term of this Contract, be
rendered unable, wholly or in part, to carry out its obligations under this
Contract, other than Customer's obligation to make payments due hereunder then,
this Contract shall continue nevertheless and shall then be deemed modified to
conform with the requirements of such law or regulation. Notwithstanding the
above, this Contract shall not be deemed to be so modified if such law or
regulation substantially and materially prohibits Company from providing
services to Customer hereunder substantially in accordance with the terms set
forth in this Contract and, in such event, Company and Customer shall negotiate
in good faith to amend the terms of this Contract such that such law or
regulation may be complied with and both Company and Customer will continue to
receive the rights and benefits herein provided. This Contract is expressly made
subject to any and all tariff and other filings made by Company and approved by
any federal or state regulatory body provided, that Company will not, without
Customer's consent, seek to alter the

General Terms - Page 13
Rev. 022790

<PAGE>

firm character of the storage services herein provided or to reduce the term of
this Contract. In the event that any regulatory body having jurisdiction over
this Contract prohibits Company from collecting rates for the services provided
hereunder which are at least equal to the rates and charges provided for in this
Contract, then Company shall have the right to terminate this Contract. In the
event that any regulatory body having jurisdiction requires Company to collect
rates for services provided hereunder which are in excess of the rates herein
provided, then Customer shall have the right to terminate this Contract.

                                   ARTICLE IX

                                  FORCE MAJEURE

         9.1      In the event of either party hereto being rendered unable,
wholly or in part, by force majeure to carry out its obligations under this
Contract, other than to make payments hereunder (except as provided in section
9.3 below), the obligations of the party, as far as they are affected by such
force majeure, shall be suspended during the continuance of any inability so
caused, but for no longer period, and such cause shall as far as possible be
remedied with all reasonable dispatch. The party so affected by such event of
force majeure shall give written notice, including reasonably full particulars
of such force majeure, in writing or by telegraph to the other party as soon as
possible but in no event more than ten (10) days after the occurrence of the
cause so relied upon.

General Terms - Page 14
Rev. 022790

<PAGE>

         9.2      The term "force majeure" as employed herein shall mean,
without limitation, acts of God, strikes, lockouts, or other industrial
disturbances, acts of the public enemy, wars, blockades, insurrection, riots,
epidemics, landslides, lightning, earthquakes, fires, storms, floods, washouts,
arrest and restraints of governments and people, civil disturbances, explosions,
breakage and/or accidents to machinery, lines or pipe, freezing of lines of
pipe, inability to obtain or delay in obtaining rights-of-way, material,
supplies, labor or permits, or refusal by pipelines, which are transporting on
Customer's behalf, to receive or deliver gas hereunder. It is understood and
agreed that the settlement of strikes or lockouts shall be entirely within the
discretion of the party having the difficulty, and that the above requirements
that any force majeure shall be remedied with all reasonable dispatch shall not
require the settlement of strikes or lockouts by acceding to the demands of any
opposing party when such course is inadvisable in the discretion of the party
having the difficulty. Company shall utilize all reasonable efforts to design,
operate and maintain its facilities in a manner which minimizes the potential
for freezing of wells or lines of pipe.

         9.3      In the event that Company is, due to an event of force
majeure, as herein defined, unable to provide storage services, in whole or in
part, under this Contract, then the obligation of Customer to make payment of
demand charges hereunder shall thereafter be waived or reduced proportionately
until service is again made available hereunder.

General Terms - Page 15
Rev. 022790

<PAGE>

                                    ARTICLE X

                             DEFAULT AND TERMINATION

         10.1     If either party hereto shall fail to perform any of the
covenants or obligations imposed upon it by virtue of this Contract (except
where such failure shall be excused under any of the provisions hereof), then in
such event the other party may, at its option, terminate this Contract by
proceeding as follows: the party not in default shall cause a written notice to
be served upon the party in default, stating specifically the cause for
terminating this Contract and declaring it to be the intention of the party
giving the notice to terminate the same; whereupon, the party in default shall
have thirty (30) days after receipt of the aforesaid notice in which to remedy
or remove the cause or causes of default stated in the notice of termination and
if, within said period of thirty (30) days, the party in default does so remedy
and remove said cause or causes, and fully indemnifies the party not in default,
then such notice shall be nullified and this Contract shall continue in full
force and effect. In the event the party in default does not so remedy and
remove the cause or causes of default, or does not fully indemnify the party
giving the notice for such party's actual damages as a result of such default
within said period of thirty (30) days, then this Contract shall become null and
void from and after the expiration of said period; provided, however, that if
such default be remedied but no indemnification therefor has been made due to a
bona fide dispute between the parties as to the amount thereof, then this
Contract

General Terms - Page 16
Rev. 027790

<PAGE>

shall not terminate, but the party not in default shall have the right to seek
recovery of its actual damages as provided by law. Any termination for breach of
this Contract shall be carried out strictly in accordance with this section.
Nothing in this Section 10.1 shall be construed to limit in any way the remedies
available to either party for breach of this Contract except for the right to
terminate.

         10.2     Any cancellation of this Contract pursuant to the provisions
of this Article X shall be without prejudice to the right of the party not in
default to collect any amounts then due it and without waiver of any other
remedy to which the party not in default may be entitled.

         10.3     In the event of termination, cancellation or expiration of
this Contract and, upon such occurrence, there is gas in storage for Customer's
account, this Contract shall continue in force and effect for the sole purpose
of withdrawal and delivery of and payment for storage services of said gas for
an additional ninety (90) days.

General Terms - Page 17
Rev. 021790

<PAGE>

                                   EXHIBIT "B"
                         TO GAS STORAGE CONTRACT BETWEEN
                    HATTIESBURG INDUSTRIAL GAS SALES COMPANY
                       AND MISSISSIPPI VALLEY GAS COMPANY
                           EFFECTIVE FEBRUARY 21, 1990

<TABLE>
<CAPTION>
                                                                Maximum Quantity
POINT(S) OF DELIVERY                                              (In MMBtu's)
--------------------                                            ----------------
<S>                                                             <C>
Interconnection between the Storage Facilities and the               5,000
pipeline facilities of Transco in Covington County,
Mississippi

Interconnection between the Storage Facilities and the               5,000
pipeline facilities of Tennessee in Forrest County,
Mississippi
</TABLE>

Gas may be scheduled for delivery at either or both of the Points of Delivery,
in quantities up to the maximum quantities indicated for each such point, but
the cumulative total of deliveries at both Points of Delivery shall not exceed
the MDIQ stated in the Contract, unless otherwise agreed by Company.

<TABLE>
<CAPTION>
                                                                Maximum Quantity
POINT(S) of REDELIVERY                                            (In MMBtu's)
----------------------                                          ----------------
<S>                                                             <C>
Interconnection between the Storage Facilities and the               10,000
pipeline facilities of Transco in Covington County,
Mississippi

Interconnection between the Storage Facilities and the               10,000
pipeline facilities of Tennessee in Forrest County,
Mississippi
</TABLE>

Gas may be scheduled for delivery at either or both of the Points of Redelivery,
in quantities up to the maximum quantities indicated for each such point, but
the cumulative total of deliveries at both Points of Redelivery shall not exceed
the MDWQ stated in the Contract, unless otherwise agreed by Company.