<PAGE>   1
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                                                   EXHIBIT 10(n)
================================================================================


                    AMENDED AND RESTATED AGREEMENT FOR LEASE

                                     between

                  Trinidad Ammonia Company, Limited Partnership

                                       and

                          PCS Nitrogen Fertilizer, L.P.

                            Dated as of May 16, 1997

================================================================================



            THIS AMENDED AND RESTATED AGREEMENT HAS BEEN ASSIGNED AS
             SECURITY FOR INDEBTEDNESS OF THE OWNER. SEE SECTION 17.

This Amended and Restated Agreement has been manually executed in 8
counterparts, numbered consecutively from 1 through 8, of which this is No.
____. To the extent, if any, that this Amended and Restated Agreement
constitutes chattel paper (as such term is defined in the Uniform Commercial
Code as in effect in any jurisdiction), no security interest in this Amended and
Restated Agreement may be created or perfected through the transfer or
possession of any counterpart other than the original counterpart which shall be
the counterpart identified as counterpart No. 1.
<PAGE>   2
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                    AMENDED AND RESTATED AGREEMENT FOR LEASE


                  Amended and Restated Agreement for Lease, dated as of May 16,
1997 (as the same may be further amended, restated, modified or supplemented
from time to time as permitted by and in accordance with the Operative
Documents, this "Agreement"), between Trinidad Ammonia Company, Limited
Partnership, a Delaware limited partnership ("Owner") and PCS Nitrogen
Fertilizer, L.P. (formerly Arcadian Fertilizer, L.P.), a Delaware limited
partnership, individually and, to the extent provided for herein, as agent of
Owner (in either such capacity, the "Agent").

                  Owner and Agent entered into an Agreement for Lease, dated as
of June 29, 1995, as amended, and said parties now desire to further amend and
restate said Agreement for Lease. Accordingly, said Agreement for Lease and all
Exhibits thereto are hereby amended and restated in their entirety as herein
provided:

                  WHEREAS, Owner may from time to time acquire either (i) a fee
interest or (ii) a leasehold interest pursuant to a Ground Lease (hereinafter
defined) in certain Unit Premises (hereinafter defined); and

                  WHEREAS, on or about the date of this Agreement, Owner and
Agent propose to enter into the Lease (hereinafter defined), providing for the
lease or sublease by Agent of certain Unit Improvements (hereinafter defined)
which will be constructed and furnished on such Unit Premises pursuant to the
terms of this Agreement; and

                  WHEREAS, Owner desires to appoint Agent to act as agent for
Owner in connection with the selection of Owner's fee and/or leasehold interests
in Unit Premises from time to time, and with the construction of Unit
Improvements and the installation of Unit FF&E thereon, if any, and in
connection with all matters related to such construction, and Agent wishes to
accept such appointment.

                  NOW, THEREFORE, in consideration of the mutual covenants
herein contained and other valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, Owner and Agent hereby agree as follows:

                  SECTION 1. DEFINITIONS

                  1.1 Defined Terms. For the purposes of this Agreement each of
the following terms shall have the meaning specified with respect thereto:

                  Accrued Default Obligations: Defined pursuant to paragraph (e)
of subsection 11.2 hereof.
<PAGE>   3
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  Acquisition Certificate: The written certification of Agent to
be delivered to Owner in connection with the making of the Initial Advance
hereunder, which contains the information and representations of Agent as
required by Section 4 of this Agreement, and which is substantially in the form
of Exhibit C hereto.

                  Affiliate: Defined pursuant to subsection 1.2 hereof.

                  AFL Unit Leasing Record: An instrument, substantially in the
form of Exhibit B hereto, evidencing the lease of a Unit under the Lease.

                  Agent: PCS Nitrogen Fertilizer, L.P. (formerly Arcadian
Fertilizer, L.P.), a Delaware limited partnership.

                  Agreement: This Amended and Restated Agreement for Lease, as
the same may be further amended, restated, modified or supplemented from time to
time pursuant to and in compliance with the Operative Documents.

                  Ammonia Project: The Unit Premises located in the Republic of
Trinidad and Tobago and described on Exhibit J hereto in which Owner will,
subject to the provisions hereof, acquire a leasehold interest and the related
Unit Improvements and Unit FF&E constituting the ammonia production plant which
are to be located on or about such Unit Premises, as described in Exhibit J
hereto.

                  Ancillary Facility Agreement: Any of the contracts entered
into by Agent or an Affiliate of Agent and assigned to Owner which provide for
the use of and access to storage tanks, loading and unloading facilities,
pipelines and similar facilities and equipment necessary for the operation and
maintenance of and access to the Ammonia Project as listed on Exhibits M-1
through M-3 hereto and the License Agreement relating to pipelines and similar
facilities necessary for the operation and maintenance of the Ammonia Project.

                  Ancillary Facility Agreement Consents: Each Estoppel
Certificate, Consent and Agreement (including all acknowledgments with respect
thereto) relating to an Ancillary Facility Agreement entered into by the
National Energy Corporation of Trinidad and Tobago Limited, the Trinidad and
Tobago Electricity Commission and the Water and Sewage Authority of Trinidad and
Tobago and the consent of Point Lisas relating to the Sublease Agreement.

                  Assignee:  Defined pursuant to subsection 1.2 hereof.

                  Assignment Agreements: Each agreement entered into between an
Affiliate of Agent and Owner, pursuant to which such Affiliate's rights under
the Gas Contract, each Ancillary Facility Agreement and each License Agreement
are assigned to Owner.

                                        2
<PAGE>   4
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  Business Day:  Defined pursuant to subsection 1.2 hereof.

                  Casualty Event: Any of the events specified in subsection 11.5
hereof.


                  Certificate of Increased Cost: The certificate delivered by
Agent to Owner pursuant to Section 7 hereof in connection with a request for a
Completion Advance, and which is substantially in the form of Exhibit F hereto.

                  Certificate of Substantial Completion: The certificate
delivered by Agent to Owner pursuant to Section 6 hereof in connection with a
request for a Final Advance, and which is substantially in the form of Exhibit E
hereto.

                  Completion Advance: Any advance made by Owner upon
satisfaction or waiver of the conditions set forth in Section 7 hereof.

                  Consent:  Defined pursuant to subsection 1.2 hereof.

                  Construction Agreement: Each agreement between Owner and a
General Contractor, providing for the construction of Unit Improvements, as the
same may be amended, restated, modified or supplemented from time to time
pursuant to and in compliance with the Operative Documents. A copy of the
Construction Agreement related to the Ammonia Project is attached as Exhibit L
hereto.

                  Construction Agreement Surety: Each of (i) a retainage letter
of credit which will periodically increase to reflect amounts entitled to be
retained from progress payments up to a maximum of $2,500,000 issued by a bank
or other financial institution reasonably acceptable to Owner and General
Contractor, for the account of the General Contractor of the Ammonia Project for
the benefit of Owner and its transferees and assigns and (ii) the guaranty of
Mannesmann Capital Corporation, or other Affiliate of the General Contractor
reasonably acceptable to Owner, in the amount of $7,500,000, furnished by the
General Contractor of the Ammonia Project for the benefit of Owner.

                  Construction Documents: The collective reference to the
Construction Agreement(s), the Unit Plans, the Permits and all other agreements
entered into by Agent or its Affiliate with respect to constructing, equipping,
furnishing and decorating the Unit.

                  Credit Agreement: Defined pursuant to subsection 1.2 hereof.

                  Debt: Defined pursuant to subsection 1.2 hereof.


                                        3
<PAGE>   5
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  Designated Effective Date: Twenty-four (24) months from the
date on which the Initial Advance is made by Owner to Agent pursuant to Section
4 hereof.

                  Effective Date: Defined pursuant to subsection 1.2 hereof.

                  Environmental Consultant:  Pilko & Associates, Inc.

                  ERISA: Defined pursuant to subsection 1.2 hereof.

                  ERISA Event:  Defined pursuant to subsection 1.2 hereof.

                  Event of Default: Any of the events constituting an Event of
Default, as specified in subsection 11.1 hereof.

                  Event of Unit Termination: Any of the events constituting an
Event of Unit Termination, as specified in subsection 11.3 hereof.

                  Final Advance:  Any advance made by Owner upon satisfaction or
waiver of the conditions of Section 6 hereof.

                  Financing Costs: All interest costs (including, without
limitation, interest at a default rate), other costs, fees and expenses incurred
by or accrued to any date for the determination thereof for the account of Owner
under a Credit Agreement, and all costs, fees and expenses incurred by or
accrued for the account of Owner to such date in connection with obtaining
equity financing, including return on equity capital and interest on overdue
payments thereof.

                  Fiscal Quarter: Any of the three-month periods ending on the
last day of March, June, September and December in each year.

                  Force Majeure Delay: Any delay caused by conditions beyond the
control of Agent or any of its Affiliates (assuming that Agent and its
Affiliates are in compliance with their obligations under the Operative
Documents), including, without limitation, acts of God or the elements, fire,
strikes, labor disputes, delays in delivery of material and disruption of
shipping, which does not have the effect of extending the Unit Completion Date
for the relevant Unit beyond two hundred and seventy (270) days in the
aggregate.

                  Gas Contract: The Gas Supply Contract dated November 25, 1994
between the National Gas Company of Trinidad and Tobago Limited and Arcadian
Trinidad Ammonia Limited (which by novation assigned its obligations, rights and
benefits thereunder to Arcadian Trinidad Limited, currently PCS Nitrogen
Trinidad Limited) by agreement dated January 27, 1997.


                                        4
<PAGE>   6
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  General Contractor: Any contractor or contractors as may be
engaged by Agent or its Affiliate from time to time for construction of Unit
Improvements. The General Contractor for the Ammonia Project is KTI Fish, Inc.

                  Governmental Action: Any action as defined in subsection 8.5
hereof.

                  Governmental Authority: Any nation or government, any state or
other political subdivision thereof, and any entity exercising executive,
legislative, judicial, regulatory or administrative functions of or pertaining
to government, or agencies, courts or arbitral panels having jurisdiction over
or application to any Unit Premises, Unit Improvements, Unit FF&E, Unit, Agent,
any Affiliate of Agent or Owner.

                  Ground Lease: Each ground lease, including, without
limitation, the Site Lease and the Sublease (each of which Site Lease and
Sublease must be a Mortgageable Ground Lease) and each additional lease under
which a leasehold interest in a Unit Premises is leased to Owner or is subleased
to Agent or a Permitted Sublessee (as defined in the Lease).

                  Guarantor: Potash Corporation of Saskatchewan Inc., a
corporation organized under the laws of the Province of Saskatchewan, and an
Affiliate of Agent, and its successors.

                  Indemnified Person: Any Person as defined in Section 12
hereof.

                  Initial Advance: Any advance made by Owner upon satisfaction
or waiver of the conditions set forth in Section 4 hereof.

                  Insurance Requirements: Defined pursuant to subsection 1.2
hereof.

                  Interim Advance:  Any advance made by Owner to Agent upon
satisfaction or waiver of the conditions set forth in Section 5 hereof.

                  Interim Advance Certificate: A certificate delivered by Agent
to Owner pursuant to Section 5 hereof in connection with a request for an
Interim Advance, and which is substantially in the form of Exhibit D hereto.

                  Lease: The Lease Agreement, dated as of June 29, 1995, by and
between Owner, as lessor, and Agent, as lessee, as amended (the "Original
Lease"), as further amended and restated as of the date hereof and as it may be
further amended, restated, modified or supplemented from time to time pursuant
to, and in compliance with, the provisions of the Operative Documents. A copy of
the Lease is attached as Exhibit A hereto.


                                        5
<PAGE>   7
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  Legal Requirements: All laws, judgments, decrees, ordinances
and regulations and any other governmental rules, orders and determinations and
all requirements having the force of law of Governmental Authorities, now or
hereinafter enacted, made or issued, whether or not presently contemplated,
including, without limitation, compliance with all requirements of labor laws
and environmental statutes (including, without limitation, all environmental
laws and statutes of the Republic of Trinidad and Tobago), compliance with which
is required at any time from the date hereof through the term of this Agreement,
whether or not such compliance shall require structural, unforeseen or
extraordinary changes to any Unit or the operation, occupancy or use thereof,
except any thereof promulgated by a Governmental Authority of the jurisdiction
of organization of Owner with application exclusively to Owner.

                  License Agreements: Defined pursuant to subsection 1.2 hereof.

                  Lien: Defined pursuant to subsection 1.2 hereof.

                  Material Subsidiaries: Potash Corporation of Saskatchewan
Sales Limited, LLC, PCS Nitrogen, Inc., PCS Phosphate Company, Inc. and any
other subsidiary of the Guarantor whose book value of assets is greater than 20%
of the book value of the assets of the Guarantor on a consolidated basis or
whose gross sales are greater than 20% of the gross sales of the Guarantor on a
consolidated basis.

                  Merrill Leasing: ML Leasing Equipment Corp., a Delaware
corporation.

                  Merrill Lynch: Merrill Lynch & Co., Inc., a Delaware
corporation.

                  Mortgageable Ground Lease: Defined pursuant to subsection 1.2
hereof.

                  Multiemployer Plan: Defined pursuant to subsection 1.2 hereof.

                  Multiple Employer Plan: Defined pursuant to subsection 1.2
hereof.

                  Operating Agreement: Defined pursuant to subsection 1.2
hereof.

                  Operative Documents: This Agreement, the Lease, the
Construction Documents, the Project Documents, each Ground Lease, each
Assignment Agreement, the Ancillary Facility Agreement Consents, the PCS/NT Ltd.
Agreement, the Trinidad Government Agreement and the Point Lisas Agreement.

                  Operator: Defined pursuant to subsection 1.2 hereof.

                  Owner: Trinidad Ammonia Company, Limited Partnership or any
successor or successors to all of its rights and obligations as Owner hereunder.


                                        6
<PAGE>   8
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  PCS Guaranty: The guaranty agreement, dated as of the date
hereof, between the Guarantor and Owner, as the same may be amended, restated,
modified or supplemented from time to time.

                  PCS/NF Ltd.: PCS Nitrogen Fertilizer Limited (formerly
Arcadian Fertilizer Limited), a Trinidad and Tobago private limited company.

                  PCS/NT Ltd.: PCS Nitrogen Trinidad Limited (formerly Arcadian
Trinidad Urea Limited, Arcadian Trinidad Ammonia Limited and Arcadian Trinidad
Limited), a Trinidad and Tobago private limited liability company.

                  PCS/NT Ltd. Agreement: The Estoppel Certificate Consent and
Agreement dated June 29, 1995, as supplemented by the Letter Agreement dated
April 30, 1997 relating thereto in respect of the Sublease.

                  PCS Term Credit Agreement: The Term Credit Agreement, made as
of October 4, 1996, among The Bank of Nova Scotia, as Agent, the Co-Agents and
the Lenders named therein and the Guarantor.

                  Permits: All consents, licenses, building, and operating
permits required for construction, completion, and operation of any Unit in
accordance with all Legal Requirements affecting such Unit.

                  Permitted Contest: Defined pursuant to paragraph (a) of
Section 16 hereof.

                  Permitted Liens: Defined pursuant to subsection 1.2 hereof.

                  Person: Defined pursuant to subsection 1.2 hereof.

                  Plan: Defined pursuant to subsection 1.2 hereof.

                  Point Lisas: The Point Lisas Industrial Port Development
Corporation.

                  Point Lisas Agreement:  The Deed of Direct Covenant dated
June 25, 1995 and all amendments, modifications and supplements related thereto
relating to the Site Lease entered into by Point Lisas.

                  Potential Default: Any event which, but for the lapse of time,
or giving of notice, or both, would constitute an Event of Default.

                  Potential Event of Unit Termination: Any event which, but for
the lapse of time, or giving of notice, or both, would constitute an Event of
Unit Termination.


                                        7
<PAGE>   9
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  Project Documents: The Gas Contract, the Operating Agreement
and each Ancillary Facility Agreement.

                  Project Parcel: The land, together with all required
appurtenant easements thereto, which is necessary for the siting, construction
and proper operation of the Ammonia Project as described on Exhibit K hereto.

                  Responsible Officer: The President, any Vice President or
Treasurer or Assistant Treasurer of the general partner of Agent, or any other
officer or similar official of the general partner of Agent responsible for the
administration of the obligations of Agent with respect to this Agreement.

                  Site Lease: The Deed of Lease dated as of August 24, 1983
between Point Lisas and the National Energy Corporation of Trinidad and Tobago
Limited ("NEC"), which was assigned to the Operator by Deed of Assignment dated
as of September 7, 1990 between NEC and the Operator (previously Trinidad and
Tobago Urea Company Limited), as the same may be amended, restated, modified or
supplemented from time to time as permitted by and in accordance with the
Operative Documents.

                  Sublease: The Deed of Sub-Lease dated as of June 29, 1995
between Arcadian Trinidad Urea Limited (subsequently Arcadian Trinidad Limited
and currently PCS Nitrogen Trinidad Limited) and Owner as the same may be
amended, restated, modified or supplemented from time to time as permitted by
and in accordance with the Operative Documents.

                  Substantial Completion: With respect to any Unit, the
satisfaction or waiver of all requirements of Section 6 hereof.

                  Surrender Date: Defined pursuant to paragraph (a) of
subsection 11.4 hereof.

                  Taking: Any event which is described in paragraph (b) of
subsection 11.5 hereof.

                  Trinidad Government Agreement: The Estoppel Certificate,
Consent and Agreement and all amendments, modifications and supplements thereto
relating to the Gas Contract entered into by the National Gas Company of
Trinidad and Tobago Limited.

                  Unit:  Any Unit Premises and any Unit Improvements thereon and
related Unit FF&E, including without limitation the Ammonia Project.


                                        8
<PAGE>   10
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  Unit Acquisition Cost: With respect to any Unit the sum of (a)
the aggregate amount of advances made pursuant to this Agreement with respect to
the Unit and (b) all other costs of Owner (including costs incurred by Agent but
reimbursed by Owner) with respect to the Unit (except costs which are not
properly capitalized and costs for which Owner has been reimbursed or chooses,
in lieu of capitalization hereunder, to be reimbursed by Agent, pursuant to the
provisions of subsection 9.5 or Section 12 hereof) arising from the acquisition,
construction, equipping, and financing (including, without limitation, Financing
Costs and Owner's out-of-pocket expenses and fee obligations in connection
therewith) prior to the lease of the Unit under the Lease, including all rent
under any Ground Lease which is paid or prepaid by Owner. Unit Acquisition Cost
shall be reflected in the applicable AFL Unit Leasing Record, as modified by any
revised AFL Unit Leasing Record.

                  Unit Budget: The budget prepared or to be prepared by Agent
and delivered to, and approved by, Owner prior to the Initial Advance with
respect to any Unit, as amended from time to time, which budget shall set forth
in general detail costs relating to such of the following as Agent deems to be
appropriate: (a) the installation of Unit FF&E, if any, thereon; (b) all costs,
including, without limitation, the purchase price, survey and survey inspection
charges, appraisal, architectural, engineering, environmental analysis, soil
analysis and market analysis fees, title insurance premiums, brokerage
commissions, transfer fees and taxes that are customarily the responsibility of
the purchaser, closing adjustments for taxes, utilities and the like, escrow and
closing fees, recording and filing fees, the legal fees of Owner and Agent, and
all related costs and expenses incurred in acquiring and maintaining marketable
fee or leasehold title to such Unit and in leasing or subleasing such Unit to
Agent; (c) the costs of completion of the Unit Improvements in conformity with
the Unit Plans, the Construction Agreement or any contracts in replacement
thereof, including without limitation, costs of site preparation, acquiring or
granting easements and acquiring or installing equipment and all related
appliances, appurtenances, accessions, furnishings, materials and parts
(including all replacements and subsequent replacements thereto) in connection
with the completion of the Unit Improvements, making utility connections,
demolition, streets, parking areas, landscaping, development, off-site
improvements, design and related construction of the Unit Improvements and
related facilities and the cost of necessary studies, surveys, plans and
permits, insurance and examination and incidental costs and expenses related
thereto incurred in acquiring and maintaining marketable fee or leasehold title
to such Unit and in leasing or subleasing such Unit and Unit FF&E to Agent; (d)
the costs of architects', attorneys', engineers' and other professionals' fees
and disbursements, in connection with the development, planning, renovation,
construction, start-up, testing and construction financing of the Unit
Improvements, including, without limitation, the fees and disbursements of
Owner's counsel in connection with this Agreement and the duties of Owner
hereunder, the Construction Agreement, and in all other matters involving or
reasonably related to this transaction; (e) costs of all charges and assessments
for the construction, improvement, maintenance, repair and restoration of
streets, roads, walks, sewer, gas, electrical,


                                        9
<PAGE>   11
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



telephone and water lines and other improvements levied upon the Unit until the
Effective Date; (f) the costs of all insurance, real estate, property and excise
tax assessments, sales and use taxes on materials used in construction, and
other operating and carrying costs paid, accrued, or levied upon the Unit or
Owner in connection with the Unit during the period from acquisition of the Unit
Premises until the Effective Date for such Unit; (g) costs of Agent's project
representatives (inspectors, consultants, etc.) incurred in its capacity as
agent for Owner; (h) a contingency amount of up to an additional twenty percent
(20%) of the aggregate of all such projected expenditures, which shall include
Financing Costs and otherwise shall be allocated to unexpected increases in the
costs associated with such Unit; and (i) any and all other costs arising from or
in connection with the construction period for such Unit Improvements during the
term of this Agreement. The Unit Budget with respect to the Ammonia Project
shall not exceed $83,000,000. A copy of the revised Unit Budget with respect to
the Ammonia Project is attached as Exhibit O hereto.

                  Unit Completion Date: With respect to the Ammonia Project,
thirty (30) months from the date on which the Initial Advance is made by Owner
to Agent pursuant to Section 4 hereof plus any Force Majeure Delay, and with
respect to any other Unit, as agreed to in writing among Agent, Owner and any
Assignee.

                  Unit FF&E: The specific items of furniture, fixtures and
equipment, if any, from the Unit FF&E Specifications which are installed or (if
such items have been acquired by Owner for installation) to be installed in a
particular Unit Improvement and any replacement parts thereof and for which
advances are made by Owner hereunder.

                  Unit FF&E Specifications: The list of furniture, fixtures and
equipment to be installed with the proceeds of advances hereunder in a
particular Unit Improvement, a copy of which with respect to the Ammonia Project
is attached as Exhibit G hereto.

                  Unit Improvements: The improvements to be constructed on an
individual Unit Premises in accordance with the Unit Plans for the Unit
Improvements to be built on such Unit Premises.

                  Unit Plans: The plans and specifications for the construction
and operating characteristics of any Unit Improvements, including, without
limitation, installation of curbs, sidewalks, gutters, landscaping, utility
connections (whether on or off the Unit Premises) and all fixtures necessary for
construction, operation and occupancy of the Unit and certain equipment to be
used in connection therewith, prepared or to be prepared by an architect and
Agent and approved by Owner, including such amendments, modifications and
supplements thereto as may from time to time be made by Agent; provided that any
subsequent material deviation from the Unit Plans selected for the Unit shall be
made only with Owner's prior consent, which consent shall not be unreasonably
withheld or delayed.


                                       10
<PAGE>   12
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  Unit Premises: Each individual parcel of land, in which either
a fee interest or a leasehold interest has been acquired by Owner for the
construction of Unit Improvements thereon, including without limitation the
Project Parcel.

                  Withdrawal Liability: Defined pursuant to subsection 1.2
hereof.

                  1.2 Other Definitional Provisions.

                  (a) For purposes of this Agreement, the terms "Affiliate",
"Assignee", "Business Day", "Consent", "Credit Agreement", "Debt", "Effective
Date", "ERISA", "ERISA Event", "Insurance Requirements", "License Agreement",
"Lien", "Mortgageable Ground Lease", "Multiemployer Plan", "Multiple Employer
Plan", "Operating Agreement", "Operator", "Permitted Liens", "Person", "Plan",
and "Withdrawal Liability" shall have the meanings set forth opposite those
terms in the Lease, except that, for purposes of this Agreement, the terms "the
Lessor", "the Lessee" and "this Lease" if used in those definitions in the Lease
shall be deemed to be the terms "Owner", "Agent" and "this Agreement",
respectively, and if used in those definitions in the Lease, each of the terms
"Parcel", "Parcel of Property" and "Property" shall be deemed to be the phrase
"Unit Premises and related Unit Improvements" and each of the terms "Unit of
Equipment" and "Unit", shall be deemed to be an item of "Unit FF&E".

                  (b) All terms defined in this Agreement shall have their
defined meanings when used in any certificate or other document made or
delivered pursuant hereto.

                  (c) The words "hereof", "herein" and "hereunder" and words of
similar import when used in this Agreement shall refer to this Agreement as a
whole and not to any particular provision of this Agreement, and section,
subsection, paragraph, schedule and exhibit references are to this Agreement
unless otherwise specified.

                  SECTION 2. APPOINTMENT OF AGENT

                  2.1 Appointment and Duties of Agent. Subject to the terms
hereof, including, without limitation, the requirements of Section 4 hereof,
Owner hereby appoints Agent as its agent for the design, construction,
equipping, and installation of the Ammonia Project on the Project Parcel in
accordance with the Unit Plans and Unit Budget and, to the extent identified in
Exhibit G hereto, Unit FF&E with respect thereto and Agent hereby accepts such
appointment. By written agreement, Owner may appoint Agent as its agent in
respect of additional Unit Premises and Unit Improvements. Unit Improvements
must be of a type permitted to be leased under the Lease, as set forth in
Exhibit A to the Lease. Agent agrees to contract for, supervise and achieve the
good, workmanlike and timely completion of the Unit Improvements


                                       11
<PAGE>   13
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



and installation of Unit FF&E on each Unit Premises in accordance with the Unit
Budget and in all material respects in accordance with the Unit Plans, suitable
for its intended use. Owner and Agent agree that any obligation of Agent
herewith may be performed by an Affiliate of Agent; provided that Agent shall in
no event be relieved of any of its obligations under this Agreement by virtue of
any such performance. Upon request of Agent, Owner agrees to deliver to Agent a
separate executed power of attorney confirmatory of the power granted herein in
form suitable for recording. Owner and Agent agree that Agent shall be
responsible for the supervision of all matters relating to any Construction
Agreement; provided that, with respect to any Construction Agreement relating to
the Ammonia Project, all obligations of Owner under such Construction Agreement
shall be performed on Owner's behalf by PCS/NF Ltd., an Affiliate of Agent;
provided, however, that Agent shall not be relieved of any of its obligations
hereunder.

                  2.2 Cost and Completion of a Unit. Owner and Agent agree that
(a) Unit Acquisition Cost shall be no more than $83,000,000 with respect to the
Ammonia Project and such amount as Agent, Owner and any Assignee agree in
writing with respect to any other Unit. Agent agrees to effect Substantial
Completion of any Unit Improvements on or before the applicable Unit Completion
Date. After receiving the Initial Advance with respect to a Unit, Agent may from
time to time amend, restate, modify or supplement the Unit Plans, Unit Budget or
Unit FF&E Specifications relating thereto; provided that no such amendment,
modification or supplement shall increase the Unit Budget to an amount in excess
of the maximum cost for acquisition set forth in the first sentence of this
subsection 2.2 or result in the Unit not being completed on or prior to its Unit
Completion Date in all material respects in accordance with the Unit Plans.
Agent shall promptly deliver to Owner and any Assignee any such amended,
modified or supplemented Unit Plans, Unit Budget or Unit FF&E Specifications.

                  2.3 Lease of a Unit.

                  (a) Upon Substantial Completion of any Unit, Agent will
deliver to Owner the Certificate of Substantial Completion in the form of
Exhibit E hereto with respect to such Unit (including, without limitation, the
AFL Unit Leasing Record), and Agent shall request the Final Advance with respect
to such Unit. If the conditions set forth in Section 6 hereof have been
satisfied in the reasonable judgment of Owner, Owner, within five (5) Business
Days of receipt of the Certificate of Substantial Completion, a fully completed
AFL Unit Leasing Record executed by Agent and the other documents required in
Section 6 hereof, shall execute and deliver to Agent such AFL Unit Leasing
Record. Except as provided below, the Final Advance shall be made by Owner on
the date of execution by Owner of the AFL Unit Leasing Record. If Substantial
Completion of the Unit will not be effected on or before the Designated
Effective Date with respect to the Unit, Agent shall prepare and execute an AFL
Unit Leasing Record with respect to the Unit and deliver it to Owner, at least
five (5) days prior to the Designated Effective Date. Owner shall execute and
deliver to Agent the


                                       12
<PAGE>   14
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



AFL Unit Leasing Record by the Designated Effective Date, and Owner's obligation
to make further advances, other than Completion Advances, with respect to the
Unit under this Agreement shall terminate on the Designated Effective Date.
Agent may request and receive on the Designated Effective Date an advance
pursuant to Section 5, provided all conditions to such advance under Section 5
are met. Such AFL Unit Leasing Record shall have an Effective Date as of the
date of the Designated Effective Date. Execution and delivery by Agent of the
AFL Unit Leasing Record shall constitute (i) acknowledgment and representation
by Agent that each Unit included therein (taking into account its then current
state of construction) is in good condition, conforms in all material respects
to the Unit Plans and has been accepted for lease under the Lease by Agent as of
the Effective Date of the AFL Unit Leasing Record, (ii) acknowledgment by Agent
that each such Unit is subject to all of the covenants, terms and conditions of
the Lease, and (iii) certification by Agent that the representations and
warranties contained in Section 2 of the Lease are true and correct in all
material respects on and as of the Effective Date of the AFL Unit Leasing Record
as though made on and as of such date and that there exists on such date no (1)
Event of Default or, with respect to such Unit, Event of Unit Termination or
Casualty Event under this Agreement or Event of Default (as defined in the
Lease) or (2) Potential Default or, with respect to such Unit, Potential Event
of Unit Termination under this Agreement or Potential Default (as defined in the
Lease). Upon execution and delivery of an AFL Unit Leasing Record by Owner, such
Unit shall become a Parcel of Property (as defined in the Lease).

                  (b) Notwithstanding the foregoing, but subject to the terms of
subsection 3.1 hereof, Agent may, by delivering to Owner a Certificate of
Increased Cost (in the form of Exhibit F hereto), at any time up to May 15,
1998, request Completion Advances in order to pay construction costs that were
not the subject of any previous advance. Owner, within five (5) Business Days of
receipt and upon Owner's approval of a request for a Completion Advance and the
Certificate of Increased Cost, shall execute and deliver to Agent a revised AFL
Unit Leasing Record for such Unit reflecting such increased cost, and Agent,
within five (5) Business Days of receipt of such revised AFL Unit Leasing
Record, shall sign the revised AFL Unit Leasing Record and return it to Owner. A
Completion Advance shall be made by Owner upon receipt of the revised AFL Unit
Leasing Record signed by Agent. Execution and delivery by Agent of the revised
AFL Unit Leasing Record shall constitute (i) acknowledgment and representation
by Agent that each Unit included therein is in good condition, conforms in all
material respects to the Unit Plans and has been accepted for lease under the
Lease by Agent as of the Effective Date of the AFL Unit Leasing Record, (ii)
acknowledgment by Agent that each such Unit is subject to all of the covenants,
terms and conditions of the Lease, and (iii) certification by Agent that the
representations and warranties contained in Section 2 of the Lease are true and
correct in all material respects on and as of the Effective Date of the revised
AFL Unit Leasing Record as though made on and as of such date and that there
exists on such date no (1) Event of Default or, with respect to such Unit, Event
of Unit Termination


                                       13
<PAGE>   15
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



or Casualty Event under this Agreement or Event of Default (as defined in the
Lease) or (2) Potential Default or, with respect to such Unit, Potential Event
of Unit Termination under this Agreement or Potential Default (as defined in the
Lease).

                  2.4 Powers of Agent. Agent shall have the right to act for and
on behalf of Owner with full and complete authority to appear before each
applicable Governmental Authority to resolve issues related to the platting,
zoning and use of the Unit Premises, to obtain all Permits, to grant and obtain
easements for the benefit of any Unit Premises or which are reasonably deemed
necessary by Agent for the installation or operation of the Ammonia Project
(provided that no such action shall contravene any provision of any Ground
Lease) in all material respects in accordance with the Unit Plans, appoint,
employ and deal with the architects, engineers, consultants and contractors,
purchase and arrange for delivery of all materials, supplies, furniture,
fixtures, and equipment, and to approve all related vouchers, invoices and
statements. Notwithstanding the foregoing, Owner agrees to execute directly any
and all such documents which Governmental Authorities do not permit to be
exercised pursuant to a power of attorney or as Agent may reasonably deem to be
necessary to effect the purposes of this Agreement. No payment shall be made for
any property or services of such architects, engineers, consultants, or
contractors relating to the acquisition, construction and equipping of any Unit
without the prior approval of Agent, and each amount so approved and paid shall
be in accordance with the Unit Budget, and shall be part of the Unit Acquisition
Cost of such Unit. If Agent has unreasonably delayed or withheld giving the
approvals required to make such payments, Owner may make payments to any
architects, engineers, consultants, contractors, vendors or suppliers which are
properly due and payable in accordance with the contracts with said parties, and
any such payment so made shall be and become a part of the Unit Acquisition Cost
of the Unit; provided, however, that Owner shall not make any such payment if it
is subject to a Permitted Contest.

                  SECTION 3. ADVANCES

                  3.1 Agreement to Make Advances. Subject to the conditions and
upon the terms herein provided, including, without limitation, that the Unit
Budget not be exceeded, Owner agrees to make available to Agent advances from
time to time for each Unit up to an aggregate principal amount for such Unit
determined in accordance with the Unit Budget for such Unit and not in excess of
the maximum amount per Unit set forth in subsection 2.2 hereof. Subject to the
terms of this Agreement, Owner agrees to make (a) an Initial Advance with
respect to a Unit in accordance with Section 4 of this Agreement, (b) Interim
Advances from time to time in accordance with Section 5 of this Agreement, (c) a
Final Advance in accordance with Section 6 of this Agreement and (d) Completion
Advances in accordance with Section 7 of this Agreement.


                                       14
<PAGE>   16
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  3.2 Procedure for Advances. Agent shall give Owner notice in
accordance with Sections 4, 5, 6 and 7 hereof of its irrevocable request for an
advance pursuant to this Agreement, specifying a Business Day on which such
advance is to be made and the amount of the advance. Not later than 2:00 P.M.
New York time on the date for the advance specified in such notice, provided
that all conditions to that advance have been satisfied, Owner shall provide to
Agent, or to such other party as may be designated by Agent, in immediately
available funds, the amount of the advance then requested.

                  3.3 Determination of Amounts of Advances.

                  (a) Initial Advance. The amount of the Initial Advance with
respect to a Unit shall be made within the limits of the Unit Budget and in
accordance with the Acquisition Certificate, and shall be sufficient to pay in
full all components of Unit Acquisition Cost paid or incurred to the date
thereof including acquisition and closing costs of the respective Unit
including, without limitation, the purchase price, survey and survey inspection
charges, recording and filing fees, brokerage commissions, appraisal,
architectural, engineering, environmental analysis, soil analysis and market
analysis fees, transfer fees and taxes that are customarily the responsibility
of the purchaser, title insurance premiums, closing adjustments for taxes,
utilities, and the like, escrow fees, if any, construction materials and
existing structures, and the legal fees of Owner and Agent. All such costs for
which the Initial Advance is requested shall be set forth in the Unit Budget
attached to the Acquisition Certificate, and in the request for the Initial
Advance.

                  (b) Interim Advances. Disbursements for the payment of or the
reimbursement of Agent for components of Unit Acquisition Cost for a Unit shall
be made upon the request of Agent from time to time, based upon the
certifications of Agent contained in an Interim Advance Certificate. Owner shall
have no obligation to make Interim Advances more often than once every seven (7)
days.

                  (c) Final Advance. The amount of the Final Advance shall be
made within the limits of the Unit Budget and in accordance with the Certificate
of Substantial Completion, and shall be sufficient, subject to the provisions of
paragraph (d) of this subsection 3.3, the payment of or the reimbursement of
Agent for components of Unit Acquisition Cost in connection with Substantial
Completion of the Unit, free of all Liens other than Permitted Liens. Owner
shall have no obligation to make the Final Advance unless Owner is satisfied
that all such costs as set forth in the Unit Budget, the Certificate of
Substantial Completion, and the request for the Final Advance have been actually
incurred, or in the case of punch list items will be incurred, in construction
and equipping of the Unit, free of all Liens, except for Permitted Liens and
shall not cause the Unit Acquisition Cost of the Unit to exceed the Unit Budget.


                                       15
<PAGE>   17
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  (d) Completion Advances. The amount of each Completion Advance
shall be made in accordance with and shall not exceed the amount set forth in
the Certificate of Increased Cost, shall not cause the Unit Acquisition Cost of
the Unit to exceed the Unit Budget, and shall be sufficient for payment in full
of all costs that are properly capitalizable and that were not the subject of
any previous advance with respect to such Unit. Owner shall have no obligation
to make a Completion Advance unless Owner is satisfied that all such costs were
reasonably estimated in the Unit Budget and are adequately set forth in the
Certificate of Increased Cost and will be sufficient for payment in full of all
costs with respect to such Unit.

                  3.4 Partial Advances. If any or all conditions precedent to
any advance have not been satisfied on the applicable date for a requested
advance, Owner, in its sole discretion, and with the consent of Assignee may,
but shall have no obligation to, disburse a part of the requested advance.

                 SECTION 4. CONDITIONS PRECEDENT TO THE INITIAL
                         ADVANCE WITH RESPECT TO A UNIT

                  Owner's obligation to make the Initial Advance with respect to
a Unit shall be subject both to the satisfaction of the conditions set forth in
this Section 4 and to the receipt by Owner and any Assignee of the documents set
forth in this Section 4, in each case in form and substance reasonably
satisfactory to Owner and any Assignee. Owner and any Assignee shall have at
least five (5) Business Days to review the Acquisition Certificate and its
attachments prior to making any Initial Advance.

                  The following are the documents to be received by Owner and
the conditions to be satisfied:

                  (a) Lease. With respect to the first advance only under this
         Agreement, a fully executed copy of the Original Lease.

                  (b) Acquisition Certificate. A duly executed copy of the
         Acquisition Certificate the statements in which shall be true.

                  (c) Warranty Deed. Where fee title is being acquired by Owner,
         a photocopy of the executed purchase and sale agreement and the
         warranty deed to be executed and delivered at the closing of the
         acquisition of Owner's fee interest in such Unit Premises, conveying
         marketable title to Owner, free of all Liens other than Permitted
         Liens. For purposes of the Initial Advance, Permitted Liens shall not
         include any mechanics' liens or materialmen's liens, or any taxes,
         assessments, governmental charges or levies, except to the extent that
         such taxes, assessments, governmental charges or levies are due and
         payable but not yet delinquent, and have been properly apportioned with
         the seller at closing.


                                       16
<PAGE>   18
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  (d) Memorandum of Lease Agreement. Except with respect to the
         Ammonia Project, two original counterparts of a memorandum of lease
         agreement in the appropriate form for recording in the jurisdiction in
         which the Unit Premises is located, executed by Agent, as lessee, and
         otherwise reasonably acceptable to Owner and Assignee.

                  (e) Ground Lease. Where a leasehold interest is being acquired
         by Owner, a true and complete copy of the Site Lease, the Sublease and
         each other Ground Lease, including a true and complete copy of the
         legal description of the Unit Premises, executed or intended to be
         executed and delivered at the closing of the acquisition of Owner's
         leasehold interest, in a form approved by Owner, and complying in all
         respects with this Agreement and with Section 28 of the Lease, and not
         subject to any Liens other than Permitted Liens, along with a
         memorandum of ground lease in statutory recordable form and any
         necessary estoppel certificates, recognition and attornment agreements,
         confirmations, and subordinations required by Owner's and any
         Assignee's counsel regarding the Ground Lease. For purposes of the
         Initial Advance, Permitted Liens shall not include any taxes,
         assessments, governmental charges or levies, except to the extent that
         such taxes, assessments, governmental charges or levies are due and
         payable but not yet delinquent.

                  (f) Taxes. Certification by Agent that all past and current
         taxes and assessments (excluding those which are due and payable but
         not yet delinquent) applicable in respect of the acquisition of the
         Unit or any component thereof by Owner, its leasing to Agent, or
         otherwise in connection with the transactions contemplated hereby, and
         in respect of the Unit Premises have been paid in full.

                  (g) Title Information. A copy of the underlying documents of
         record affecting fee title to the Unit Premises from the appropriate
         Governmental Authority, or such other evidence in respect of title as
         Owner may reasonably request.

                  (h) Survey. A current survey or an update of an existing
         survey of the Unit Premises prepared by a licensed public land
         surveyor, and dated a date within one hundred eighty (180) days prior
         to the date of the Initial Advance.

                  (i) Availability of Access Rights and Utilities. Certification
         by Agent that all easements, licenses, rights of way, access rights and
         utility services and facilities (including, without limitation, gas,
         electrical, water and sewage services and facilities) (i) which are
         necessary and required during the construction period have been
         completed or will be available in such a manner as to assure Owner that
         construction will not be impeded by a lack thereof and (ii) which are
         necessary for the occupancy of the Unit and the installation of the
         Unit Improvements thereon and for the completion and operation of the
         Unit in


                                       17
<PAGE>   19
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         accordance with the Unit Plans are or will be completed in such a
         manner and at such a time as will assure the completion and operation
         of the Unit on or before the Unit Completion Date.

                  (j) Permits. Certification by Agent that all Permits and
         governmental approvals required for the construction of the Unit
         Improvements (other than the governmental approval of the Town and
         Country Planning Authority of the Republic of Trinidad and Tobago,
         which approval will be obtained in the normal course) have been or will
         be issued or obtained in such a manner as to assure Owner that
         construction will not be impeded by a lack thereof and all such Permits
         and governmental approvals required therefor which have been issued or
         obtained are in full force and effect.

                  (k) Opinions of Counsel for Agent. An opinion of counsel for
         Agent, in form and substance reasonably satisfactory to Owner and
         Assignee, and an opinion of counsel for Agent licensed in the Republic
         of Trinidad and Tobago, in form and substance reasonably satisfactory
         to Owner and Assignee.

                  (l) Construction Agreement. A fully executed and complete copy
         of the Construction Agreement.

                  (m) Consent and Acknowledgement Documentation. Fully executed
         originals of the Point Lisas Agreement, the PCS/NT Ltd. Agreement, the
         Ancillary Facility Agreement Consents and the Trinidad Government
         Agreement.

                  (n) Unit Plans. A copy of the Unit Plans satisfactory to Owner
         and Assignee.

                  (o) Unit Budget. A copy of the Unit Budget and certification
         by Agent that such Unit Budget is (i) true, complete and correct, (ii)
         accurately representative at the time of delivery of all expected costs
         to Owner of the Unit and (iii) within the dollar limits set forth in
         the first sentence of subsection 2.2 hereof.

                  (p) Certificates of Insurance. Certificates of insurance or
         other evidence reasonably acceptable to Owner certifying that the
         insurance then carried or maintained on the Unit required by subsection
         9.3 hereof complies with the terms of such subsection.

                  (q) Request for Advance. A duly executed AIA Document G722 (or
         substantially similar document), stating the total amount of the
         Initial Advance requested, the date on which the advance is to be made,
         the name, address and, if applicable, the escrow reference number of
         the escrow or closing agent or


                                       18
<PAGE>   20
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         party to whom the Initial Advance is to be tendered, wiring
         instructions and an itemization of the various costs constituting the
         amount of the Initial Advance in such detail as will be necessary to
         provide disbursement instructions to the escrow or closing agent,
         including, specifically, an accounting of all expenditures for costs
         shown on the Unit Budget for which payment or reimbursement is being
         requested with respect to the Unit. A form of AIA Document G722 is
         attached hereto as Exhibit N.

                  (r) Environmental Certificate and Report. An environmental
         certificate in substantially the form of Exhibit H hereto, duly
         executed by the general partner of Agent, and an environmental report
         satisfactory to Owner and any Assignee in all respects, prepared by the
         Environmental Consultant. If Owner or Assignee shall reasonably require
         additional assurance as to any matter or matters contained or not
         adequately addressed in such environmental report, Owner or Assignee
         may require that further investigation be conducted and a supplemental
         or additional environmental report with respect to such matter or
         matters, satisfactory to Owner and Assignee in all respects, be
         delivered.

                  (s) Use of Proceeds, No Liens and Representations of Agent.
         (i) All costs and expenses which are the subject of the Initial Advance
         requested have been paid in full or will be paid in full out of the
         proceeds of the Initial Advance, (ii) there are no Liens on the Unit of
         which Agent has knowledge that are not Permitted Liens, (iii) all
         representations and warranties made in this Agreement, in the Lease and
         in connection with the Initial Advance, are and remain true and correct
         in all material respects on and as of the date of the Initial Advance
         (except to the extent such representations and warranties expressly
         relate specifically to an earlier date) and (iv) no Event of Default,
         Potential Default or, with respect to the Unit for which the Initial
         Advance is requested, Casualty Event, Event of Unit Termination or
         Potential Event of Unit Termination, under this Agreement has occurred
         and is continuing on the date such Initial Advance is to be made or by
         reason of giving effect to such Initial Advance.

                  (t) Project Documents. With respect to the Ammonia Project,
         copies of each Project Document.

                  (u) Appraisal. With respect to the Ammonia Project, an
         appraisal prepared by Arthur Andersen & Co., which appraisal shall
         include (i) a "value in use" fair market valuation of at least
         $75,000,000 as at July 1, 1996 and (ii) a "value in use" fair market
         valuation of the Ammonia Project of at least $68,800,000 as at July 1,
         2000.


                                       19
<PAGE>   21
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  (v) Assignment Agreement. With respect to the Ammonia Project,
         an executed Assignment Agreement with respect to each Ancillary
         Facility Agreement and the Gas Contract.

                  (w) Unit FF&E Specifications. A true and complete copy of the
         Unit FF&E Specifications with respect to the Unit.

                  SECTION 5.        CONDITIONS PRECEDENT TO OWNER'S
                                    OBLIGATION TO MAKE INTERIM ADVANCES
                                    AFTER THE INITIAL ADVANCE WITH RESPECT TO
                                    A UNIT

                  Owner's obligation to make any Interim Advance with respect to
a Unit after the Initial Advance with respect to such Unit shall be subject to
the satisfaction of the conditions set forth in this Section 5 and to the
receipt by Owner and any Assignee of the documents set forth in this Section 5,
in each case in form and substance reasonably satisfactory to Owner and any
Assignee. Owner and any Assignee shall have at least five (5) Business Days to
review the Interim Advance Certificate and its attachments prior to making any
Interim Advance.

                  The following are the documents to be received by Owner and
any Assignee and the conditions to be satisfied:

                  (a) Interim Advance Certificate. A duly executed Interim
         Advance Certificate the statements in which shall be true.

                  (b) Continuing Representations of Agent. All representations
         and warranties made in this Agreement, in the Lease, and in connection
         with the Interim Advance, are and remain true and correct in all
         material respects on and as of the date of the Interim Advance as if
         made on and as of the date of the Interim Advance (except to the extent
         such representations and warranties expressly relate specifically to an
         earlier date) and no Event of Default, Potential Default or, with
         respect to the Unit for which such Interim Advance is requested,
         Casualty Event, Event of Unit Termination or Potential Event of Unit
         Termination, under this Agreement has occurred and is continuing on the
         date such Interim Advance is to be made or by reason of giving effect
         to such Interim Advance.

                  (c) Construction Progress. If reasonably requested in writing
         by Owner or any Assignee at least three (3) Business Days prior to the
         making of an Interim Advance, Owner shall have received and approved
         (i) an inspection report from an independent party satisfactory to
         Owner or any Assignee, if any, covering conformity of the work to the
         Unit Plans, quality of work completed, percentage of work completed and
         (ii) true copies of unpaid invoices, receipted


                                       20
<PAGE>   22
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         bills and Lien waivers, and such other reasonably available supporting
         information as Owner or any Assignee may reasonably request.

                  (d) Evidence of Compliance. Agent shall furnish Owner and any
         Assignee with such additional or updated documents, reports,
         certificates, affidavits and other information, in form and substance
         reasonably satisfactory to Owner and any Assignee in its reasonable
         judgment, as Owner and any Assignee may reasonably require to evidence
         compliance by Agent with all of the provisions of this Agreement.

                  (e) Request for Advance. A duly executed AIA Document G722 (or
         a substantially similar document), stating the total amount of the
         Interim Advance requested, the date on which such Interim Advance is to
         be made, and a specific breakdown of items and costs for which the
         Interim Advance is being made.

                  (f) No Other Security Interests. All materials and fixtures
         incorporated in the construction of the Unit Improvements have been
         purchased so that title thereto or a leasehold interest therein, as the
         case may be, shall have vested in Owner immediately upon delivery
         thereof to the Unit Premises, except for Permitted Liens, and Agent
         shall have produced and furnished, if requested in writing by Owner at
         least three (3) Business Days prior to the making of an Interim
         Advance, the contracts, bills of sale, statements, receipted vouchers,
         or other documents under which title thereto or a leasehold interest
         therein is claimed; provided that, if Agent does not have any documents
         under which title thereto or a leasehold interest thereon is claimed,
         upon Owner's request, Agent shall use commercially reasonable efforts
         to obtain such documents.

                  (g) Statement of Expenditures. If requested in writing by
         Owner, Agent or any General Contractor shall supply Owner with a
         statement setting forth the names, addresses and amounts due or to
         become due as well as the amounts previously paid to every contractor,
         subcontractor or Person furnishing materials, performing labor or
         entering into the construction of any part of the Unit Improvements.

                  (h) Political Risk Insurance. Evidence reasonably acceptable
         to Owner that the political risk insurance required by paragraph (d) of
         Section (10) of the Lease has been obtained.

                  SECTION 6.        CONDITIONS PRECEDENT TO THE FINAL
                                    ADVANCE WITH RESPECT TO A UNIT

                  Owner's obligation to make the Final Advance with respect to a
Unit shall be subject to the satisfaction of the conditions set forth in this
Section 6 and to the


                                       21
<PAGE>   23
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



receipt by Owner and any Assignee of the documents set forth in this Section 6,
in each case in form and substance reasonably satisfactory to Owner and any
Assignee. When all of the conditions set forth in this Section 6 shall have been
satisfied to the reasonable satisfaction of Owner and any Assignee, Substantial
Completion of a Unit shall be deemed to occur. Owner and any Assignee shall have
at least five (5) Business Days to review the Certificate of Substantial
Completion and its attachments prior to making a Final Advance.

                  The following are the documents to be received by Owner and
any Assignee and the conditions to be satisfied:

                  (a) Certificate of Substantial Completion. A duly executed
         Certificate of Substantial Completion the statements in which shall be
         true.

                  (b) Construction and Equipping of the Unit. The Unit
         Improvements (including all interior finish work, but exclusive of
         punch list items) have been completed within the Unit Budget and in all
         material respects in accordance with the Unit Plans and are accepted by
         Agent.

                  (c) Permits. All Permits and governmental approvals (other
         than the governmental approval of the Town and Country Planning
         Authority of the Republic of Trinidad and Tobago, which approval will
         be obtained in the normal course) with respect to the Unit shall have
         been issued or obtained and shall be in full force and effect.

                  (d) Liens. The Unit, including interior finish work, has been
         completed as contemplated in paragraph (b) above, free of all Liens,
         except for Permitted Liens (all of which are to be itemized as to the
         nature, amount, claimant and status), and there are no current
         Permitted Contests with respect to the Unit (or, if any, the nature,
         amount, claimant and status thereof).

                  (e) Final Survey. A final survey showing the completed Unit
         Improvements, all easements on the Unit Premises, and indicating the
         location of access to the Unit Premises and all utility and water
         easements directly affecting the Unit Premises.

                  (f) Utilities. Connection has been made to all appropriate
         utility facilities and the Unit Improvements are ready for occupancy
         and operation.

                  (g) Continuing Representations of Agent. All representations
         and warranties made in this Agreement, in the Lease, and in connection
         with the Final Advance are to remain true and correct in all material
         respects on and as of the date of the Final Advance (except to the
         extent such representations and warranties expressly relate
         specifically to an earlier date) as if made on and as of


                                       22
<PAGE>   24
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         the date of the Final Advance and no Event of Default, Potential
         Default or, with respect to the Unit for which the Final Advance is
         requested, Casualty Event, Event of Unit Termination or Potential Event
         of Unit Termination, under this Agreement has occurred and is
         continuing on the date such Final Advance is to be made or by reason of
         giving effect to such Final Advance.

                  (h) AFL Unit Leasing Record. An AFL Unit Leasing Record
         prepared and duly executed by Agent. All Unit Premises and Unit
         Improvements included in the Ammonia Project shall be included on one
         (1) AFL Unit Leasing Record.

                  (i) Request for Advance. A duly executed AIA Document G722 (or
         a substantially similar document), stating the total amount of the
         Final Advance requested, the date on which such advance is to be made,
         wiring instructions and a specific breakdown of items and costs for
         which the Final Advance is to be made.

                  SECTION 7.        CONDITIONS PRECEDENT TO COMPLETION
                                    ADVANCES WITH RESPECT TO A UNIT

                  Owner's obligation to make Completion Advances with respect to
a Unit shall be subject to the satisfaction of the conditions set forth in this
Section 7 and to the receipt by Owner and any Assignee of the documents set
forth in this Section 7, in each case in form and substance reasonably
satisfactory to Owner and Assignee. The amount of a Completion Advance shall not
cause the Unit Acquisition Cost of a Unit to exceed the Unit Budget. The
proceeds of a Completion Advance shall be used to pay in full all costs relating
to completion of such Unit for which Agent has received invoices subsequent to
such Effective Date. Owner and any Assignee shall have at least five (5)
Business Days to review the Certificate of Increased Cost and its attachments
prior to making such Completion Advance.

                  The following are the documents to be received by Owner and
any Assignee and the conditions to be satisfied:

                  (a) Certificate of Increased Cost. A duly executed Certificate
         of Increased Cost the statements in which shall be true.

                  (b) Continuing Representations of Agent. All representations
         and warranties made in this Agreement, in the Lease, and in connection
         with the Completion Advance are and remain true and correct in all
         material respects on and as of the date of such Completion Advance
         (except to the extent such representations and warranties expressly
         relate specifically to an earlier date) as if made on and as of the
         date of such Completion Advance and no Event of Default, Potential
         Default or, with respect to the Unit for which such


                                       23
<PAGE>   25
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         Completion Advance is requested, Casualty Event, Event of Unit
         Termination or Potential Event of Unit Termination under this Agreement
         has occurred and is continuing on the date such Completion Advance is
         to be made or by reason of giving effect to such Completion Advance.

                  (c) Request for Advance. A duly executed AIA Document G722 (or
         a substantially similar document), stating the total amount of the
         Completion Advance requested, the date on which such advance is to be
         made, wiring instructions and a specific breakdown of items and costs
         for which such Completion Advance is to be made.

                  (d) Revised AFL Unit Leasing Record. A revised AFL Unit
         Leasing Record prepared by Agent pursuant to subsection 2.3(b) hereof.

                  (e) Representations of Guarantor. All representations and
         warranties of the Guarantor in the PCS Guaranty are and remain true and
         correct in all material respects on and as of the date of such
         Completion Advance as if made on and as of the date of such Completion
         Advance (except to the extent such representations and warranties
         expressly relate specifically to an earlier date) and no default under
         the PCS Guaranty has occurred and is continuing on the date such
         Completion Advance is to be made or by reason of giving effect to such
         Completion Advance.

                  SECTION 8.        REPRESENTATIONS AND WARRANTIES OF
                                    AGENT

                  Agent represents and warrants to Owner on the date hereof and
on the date of each advance occurring after the date hereof that:

                  8.1 Partnership Matters. Agent (i) has been duly organized and
is validly existing as a limited partnership in good standing under the laws of
the State of Delaware, (ii) has full power, authority and legal right to own and
operate its properties and to conduct its business as presently conducted and to
execute, deliver and perform its obligations under this Agreement and any other
Operative Document to which it is or is to be a party and to consummate the
transactions contemplated hereby and by the other Operative Documents and (iii)
to the best of its knowledge after due inquiry, is duly qualified to do business
as a foreign limited partnership in good standing in each jurisdiction in which
its ownership or leasing of properties or the conduct of its business or the
consummation of the transactions contemplated hereby and by the other Operative
Documents requires such qualification, except where the failure to so qualify
would not materially impair the ability of Agent to perform its obligations
hereunder or under the other Operative Documents. The sole general partner of
Agent on the date hereof is PCS Nitrogen Fertilizer Operations, Inc.


                                       24
<PAGE>   26
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  8.2 Power and Authority. The consummation by Agent of the
transactions contemplated by the Operative Documents and the execution, delivery
of and performance and observance by Agent of its obligations under this
Agreement and the other Operative Documents to which it is or is to be a party
have been duly authorized by all necessary action on the part of the partners of
Agent. None of the execution, delivery and performance by Agent of this
Agreement or any other Operative Document to which Agent is or is to be a party
will result in any violation of any term of the certificate of limited
partnership or the partnership agreement of Agent, or require the approval or
consent of any limited partner or general partner of Agent except such as have
been obtained prior to the date hereof and will not conflict with or result in a
breach in any material respect of any terms or provisions of, or constitute a
default under, or result in the creation or imposition of any Lien (other than a
Permitted Lien) upon any property or assets of Agent under, any indenture,
mortgage or other agreement or instrument to which Agent is a party or by which
it or any of its property is bound, or any existing applicable law, rule,
regulation, license, judgment, order or decree of any Governmental Authority or
court having jurisdiction over Agent or any of its activities or properties.

                  8.3 Binding Agreement. Each of this Agreement and each other
Operative Document to which Agent is or is to be a party has been duly
authorized and has been or will be duly executed and delivered by Agent and,
assuming the due authorization, execution and delivery of this Agreement and any
other such Operative Document by the parties thereto other than Agent, this
Agreement is, and each such other Operative Document when executed and delivered
will be, the legal, valid and binding obligation of Agent, enforceable against
Agent according to their terms, subject, as to enforceability, to applicable
bankruptcy, insolvency and similar laws affecting creditors' rights generally,
and to general principles of equity (regardless of whether enforcement is sought
in a proceeding in equity or at law).

                  8.4 No Litigation. Except as disclosed in the most recent
audited financial statements of the Guarantor and its consolidated subsidiaries,
the Annual Report on Form 10-K for the fiscal year ended December 31, 1996 of
the Guarantor and its consolidated subsidiaries and the Quarterly Report on Form
10-Q for the Fiscal Quarter ended March 31, 1997 of the Guarantor and its
consolidated subsidiaries, there is no action, suit, proceeding or investigation
at law or in equity by or before any court, governmental body, agency,
commission or other tribunal now pending or, to the knowledge of Agent,
threatened against or affecting Agent or any property or rights of Agent which
questions the enforceability of this Agreement or any other Operative Document
or which affects any or relates to any Unit Premises, Unit Improvements, Unit
FF&E or Unit or which, if adversely determined, would have a reasonable
possibility of causing a material adverse impact on the business of Agent in the
aggregate or would materially impair the ability of Agent to perform its
obligations hereunder or under any other Operative Document.


                                       25
<PAGE>   27
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  8.5 Consents, Approvals, Authorizations, Etc. There are no
consents, licenses, orders, authorizations, approvals, waivers, extensions or
variances of, or notices to or registrations or filings with (each a
"Governmental Action"), any Governmental Authority or public body or authority
in any jurisdiction which are or will be required in connection with or are
necessary to the valid execution, delivery and performance of this Agreement or
any other Operative Document or any Governmental Action (i) which is or will be
required in connection with any participation by Owner in the transactions
contemplated by, or the exercise of remedies or the enforcement of rights by
Owner under, this Agreement or any other Operative Document, any bill of sale,
deed, assignment, assumption, ownership agreement, or operating agreement
relating to any Unit Premises, Unit Improvements, Unit FF&E or Unit or (ii)
which is or will be required to be obtained by Owner, Agent, any Assignee or an
Affiliate of the foregoing, during the term of this Agreement, with respect to
any Unit Premises, Unit Improvements, Unit FF&E or Unit except the Governmental
Action of the Town and Country Planning Authority of the Republic of Trinidad
and Tobago, which Governmental Action Agent reasonably believes will be obtained
in the normal course, and such other Governmental Actions (A) as have been duly
obtained, given or accomplished, with true copies thereof delivered to Owner,
(B) as may be required by applicable law not now in effect, (C) which,
individually or in the aggregate, if not obtained or effected, (x) will not
place either Owner or any Assignee in any danger of any monetary civil liability
for which Owner or any Assignee is not adequately indemnified (Agent's
obligations under Section 12 of this Agreement shall be deemed to be adequate
indemnification if no Event of Default exists) or any other material civil
liability or penalty or subject Owner or any Assignee to any criminal liability
as a result of a failure to comply therewith, (y) will not result in a material
diminution in the value of any Unit Premises, Unit Improvements, Unit FF&E or
Unit or in any material risk of the loss, sale or forfeiture or loss of use of
any thereof, and (z) will not materially impair the ability of Agent to perform
its obligations hereunder, (D) as may be required for the construction or
operation of the Ammonia Project and have been or will be timely obtained or (E)
which may be required as a result of the business, properties or activities of
Owner, any Assignee or any Affiliate of the foregoing and which are not solely
dependent on the nature of the Unit Premises, Unit Improvements, Unit FF&E or
Units or the business of Agent.

                  8.6 Compliance with Legal Requirements and Insurance
Requirements. The construction, operation, use, and physical condition of each
Unit Premises, the Unit Improvements, Unit and item of Unit FF&E comply with all
Legal Requirements and Insurance Requirements; except any Legal Requirements,
the non-compliance with which, individually or in the aggregate, (i) will not
place either Owner or any Assignee in any danger of any monetary civil liability
which Owner or any Assignee is not adequately indemnified for (Agent's
obligations under Section 12 of this Agreement shall be deemed to be adequate
indemnification if no Event of Default exists) or any other material civil
liability or penalty or subject Owner or any Assignee to any criminal liability
as a result of a failure to comply therewith and (ii) will not


                                       26
<PAGE>   28
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



result in a material diminution in the value of any Unit Premises, Unit
Improvements, Unit FF&E or Unit or in any material risk of the loss, sale or
forfeiture or loss of use of any thereof.

                  8.7 No Default. Neither Agent nor the Guarantor is in
violation of or in default under or with respect to any Legal Requirement in any
respect which could have a materially adverse effect on the business,
operations, properties or financial or other condition of Agent or the
Guarantor, or which could materially adversely affect the ability of Agent to
perform its obligations under this Agreement or any other Operative Document to
which Agent is a party or the ability of the Guarantor to perform its
obligations under the PCS Guaranty.

                  8.8 Ownership; Liens. No Unit Premises, Unit Improvements,
Unit FF&E or Unit is subject to any Lien, except for Permitted Liens.

                  8.9 Financial Statements. Agent has furnished to Owner copies
of the annual audited financial statements of the Guarantor and its consolidated
subsidiaries for the fiscal year ended December 31, 1996, the Annual Report on
Form 10-K for the fiscal year ended December 31, 1996 of the Guarantor and its
consolidated subsidiaries and the Quarterly Report on Form 10-Q for the Fiscal
Quarter ended March 31, 1997 of the Guarantor and its consolidated subsidiaries.
The financial statements contained in such documents fairly present in all
material respects the financial position, results of operations and statements
of cash flows of the Guarantor and its consolidated subsidiaries taken as a
whole as of the dates and for the periods indicated therein and have been
prepared in accordance with generally accepted accounting principles applied on
a consistent basis, except as stated therein or in the notes thereto.

                  8.10 Changes. Since March 31, 1997, there has been no material
adverse change in the financial condition or business of the Guarantor and its
consolidated subsidiaries taken as a whole nor any change which would materially
impair the ability of Agent to perform its obligations under this Agreement or
any other Operative Document to which Agent is a party or the ability of the
Guarantor to perform its obligations under the PCS Guaranty.

                  8.11 Suitability of Each Unit Premises. Each Unit Premises is
suitable in all material respects (including, without limitation, ground
conditions, utilities, and condition of title) for the construction and
operation of the related Unit Improvements in all material respects in
accordance with the related Unit Plans.

                  8.12 ERISA.

                  (a) No ERISA Event has occurred or is reasonably expected to
occur with respect to any Plan.


                                       27
<PAGE>   29
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  (b) As of the last annual actuarial valuation date, the funded
current liability percentage, as defined in Section 302(d)(8) of ERISA, of each
Plan exceeds 90 percent, other than with respect to Plans whose unfunded current
liability does not exceed $1,000,000 in the aggregate, and there has been no
material adverse change in the funding status of any such Plan since such date.

                  (c) Agent has not incurred or is reasonably expected to incur
any Withdrawal Liability to any Multiemployer Plan.

                  (d) Agent has not been notified by the sponsor of a
Multiemployer Plan that such Multiemployer Plan is in reorganization or has been
terminated, within the meaning of Title IV of ERISA, and no such Multiemployer
Plan is reasonably expected to be in reorganization or to be terminated, within
the meaning of Title IV of ERISA.

                  (e) Except as set forth in the financial statements referred
to in subsection 8.9 hereof, Agent and its Subsidiaries have no material
liability with respect to "expected post retirement benefit obligations" within
the meaning of Statement of Financial Accounting Standards No. 106.

                  (f) The execution and delivery of this Agreement will not
involve any non-exempt "prohibited transaction" within the meaning of Section
406 of ERISA or Section 4975 of the Code.

                  8.13 Ground Lease. Each Ground Lease is a Mortgageable Ground
Lease, except to the extent agreed to in writing by Owner and Assignee, and is
in full force and effect and has not been modified, amended or changed in any
manner that has not been approved in writing by Owner, nor is there any material
default under any Ground Lease nor event which, with the giving of notice or the
passage of time or both, would constitute a default under such Ground Lease, nor
to the best knowledge of Agent has any party under any Ground Lease commenced
any action or given or received any notice for the purpose of terminating any
Ground Lease.

                  8.14 Operating Agreement. The Operating Agreement has been
duly authorized, executed and delivered by the Operator and, assuming the due
authorization, execution and delivery of the Operating Agreement by Owner, is a
legal, valid and binding obligation of the Operator, enforceable according to
its terms.

                  8.15 Gas Contract. The Gas Contract has been duly authorized,
executed and delivered by an Affiliate of the Agent and, assuming the due
authorization, execution and delivery of the Gas Contract by the National Gas
Company of Trinidad and Tobago Limited, is a legal, valid and binding obligation
of such Affiliate of Agent, enforceable according to its terms.


                                       28
<PAGE>   30
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  8.16 Ancillary Facility Agreements. Each Ancillary Facility
Agreement has been duly authorized, executed and delivered by Agent or an
Affiliate of Agent and, assuming the due authorization, execution and delivery
of each Ancillary Facility Agreement by the parties thereto other than Agent or
an Affiliate of Agent, is a legal, valid and binding obligation of Agent or such
Affiliate, enforceable according to its terms.

                  8.17 PCS Guaranty. The PCS Guaranty has been duly authorized,
executed and delivered by the Guarantor and constitutes a legal, valid and
binding obligation of the Guarantor, enforceable against the Guarantor according
to its terms, subject to bankruptcy, insolvency, moratorium, and similar laws
affecting creditors' rights generally and equitable principles.

                  SECTION 9. AFFIRMATIVE COVENANTS

                  Agent hereby agrees that, so long as this Agreement remains in
effect, Agent shall keep and perform fully each and all of the following
covenants:

                  9.1 Performance under Other Agreements. Agent shall duly
perform and observe in all material respects all of the covenants, agreements
and conditions on its part to be performed and observed hereunder and under each
other Operative Document to which it is a party, except to the extent that
Agent's obligation in respect of such covenant, agreement or condition may be
subject to a Permitted Contest.

                  9.2 No Encroachments. The Unit Improvements shall be
constructed entirely on the related Unit Premises and shall not encroach upon or
overhang (unless consented to by the affected property owner or permitted by the
terms of any easement, license or right-of-way agreement) any easement or
right-of-way or the land of others, and when erected shall be wholly within any
building restriction lines, however established. If Owner shall have a
reasonable basis to believe any Unit Improvements are not in compliance with
this subsection 9.2, Owner may request, and Agent shall furnish from time to
time satisfactory evidence of compliance with the foregoing covenants,
including, without limitation, a survey prepared by a surveyor or engineer. If
any discrepancies exist between the legal description set forth on the survey
described in Section 4(h) hereof and the final as-built survey described in
Section 6(f) hereof, Owner and Agent shall cooperate, at Agent's expense, in
amending the legal descriptions in all recorded documents creating or
encumbering or otherwise affecting the Unit Premises, including, without
limitation, any easements, to reflect the correct as-built description.


                                       29
<PAGE>   31
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  9.3 Insurance.

                  (a) Insurance with respect to each Unit Premises, the Unit
Improvements, Unit FF&E and Unit. Agent will maintain or cause to be maintained
on each Unit Premises, the Unit Improvements, Unit FF&E and Unit insurance of
the same types, in the same amounts and on the same terms and conditions as the
insurance required by paragraph (c) through (l) of Section 10 of the Lease,
except that the terms "Owner", "Agent" and "this Agreement" shall substitute for
the terms "the Lessor", "the Lessee" and "this Lease", respectively, the phrase
"Unit Premises, Unit Improvements, Unit FF&E and Unit" shall substitute for the
phrase "Parcel of Property" or "Property", references to "Equipment" or "Unit of
Equipment" shall be deemed deleted, and the phrase "Unit Acquisition Cost" shall
substitute for the phrase "Acquisition Cost"; provided that in lieu of the
insurance required by paragraph (c)(i) of Section 10 of the Lease, Agent shall,
as Owner's agent, maintain or cause to be maintained for Owner All Risk
Builders' Risk Completed Value Non-Reporting Form Insurance, including collapse
coverage and fire insurance with extended coverage, in an amount not less than
one hundred percent (100%) of the completed insurable value of the respective
Unit Improvements and Unit FF&E. The term "completed insurable value" as used
herein means the actual replacement cost, including the cost of debris removal,
but excluding the cost of constructing foundation and footings. Such insurance
may provide for such deductibles and Agent may self-insure with respect to the
required coverage to the extent consistent with Agent's customary practice with
respect to similar property owned by Agent.

                  (b) Use or Operation of Unit Premises, Unit Improvements, Unit
FF&E or Unit. Agent covenants that it will not use, carry on construction with
respect to, or occupy any Unit or permit the use, construction, or occupancy of
any Unit Premises, Unit Improvements, Unit FF&E or Unit at a time when the
insurance required by paragraph (a) of this subsection is not in force with
respect to such Unit Premises, Unit Improvements, Unit FF&E or Unit.

                  (c) Construction Bonding. In order to secure the performance
by the General Contractor for the Ammonia Project of its obligations under its
Construction Agreement, Agent shall furnish to Owner and maintain the
Construction Agreement Surety in such amounts and for such durations as may be
required pursuant to such Construction Agreement.

                  9.4 Inspection. Upon at least five (5) Business Days' written
notice (or upon two (2) Business Days' written notice if an Event of Default
shall have occurred and be continuing), Owner or Assignee or any authorized
representatives of either of them, shall have during reasonable business hours
the right of entry and free access to each Unit Premises, the Unit Improvements,
Unit FF&E and each Unit and the right to inspect all work done, labor performed
and materials furnished in and about each Unit Premises, the Unit Improvements,
Unit FF&E and each Unit and at


                                       30
<PAGE>   32
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



reasonable times the right to inspect all contracts of Agent relating to each
Unit Premises, the Unit Improvements, Unit FF&E and each Unit, but neither Owner
nor any Assignee shall have any duty to make any such inspection; provided that
Agent shall be permitted to withhold from Owner or any Assignee any information
with respect to its business or work products not related to any Unit Premises,
Unit Improvements, Unit FF&E or Unit. Owner may recover from Agent (i) the
reasonable costs and expenses associated with any inspection of the Ammonia
Project during the period from the date of this Agreement until the Lease
Termination Date (as defined in the Lease) with respect thereto, in an amount
not to exceed, when aggregated with the expenses referred to in clause (i) of
paragraph (d) of Section 8 of the Lease, $100,000 in the aggregate, and (ii) the
reasonable costs and expenses associated with any such inspection which are
incurred following the occurrence and during the continuation of any Event of
Default throughout the term of this Agreement.

                  9.5 Expenses. Agent shall pay, whether or not Owner is
obligated to make any Advance under Sections 3 through 7 hereof, upon demand all
obligations, costs and expenses incurred in good faith by Owner with respect to
any and all transactions contemplated herein and the preparation of any document
reasonably required hereunder and the prosecution or defense of any action or
proceeding or other litigation affecting Agent or any Unit Premises, Unit
Improvements, Unit FF&E or Unit, including (without limiting the generality of
the foregoing) all Financing Costs not capitalized by Owner in Unit Acquisition
Cost and amounts required to reimburse Owner for its obligations, costs and
expenses arising in connection with the termination of any Credit Agreement
(whether as a result of a default thereunder or otherwise), costs incurred in
connection with obligations of Owner under or in respect of any interest rate
swap, cap, collar or other financial hedging arrangement, including without
limitation costs incurred by Owner under any such arrangement to reduce the
notional amount thereof by the amount of any prepayment of any borrowing to
which such interest rate swap, cap, collar or other financial hedging
arrangement relates, title and conveyancing charges, recording and filing fees
and taxes, title search fees, rent under the Ground Leases, mortgage taxes,
intangible personal property taxes, escrow fees, revenue and tax stamp expenses,
insurance premiums (including title insurance premiums), brokerage commissions,
finders' fees, placement fees, court costs, surveyors', photographers',
appraisers', architects', engineers', accountants' and reasonable attorneys'
fees and disbursements, and will reimburse to Owner all expenses paid by Owner
of the nature described in this subsection 9.5 which have been or may be
incurred by Owner with respect to any and all of the transactions contemplated
herein. In the event Agent shall fail to reimburse Owner within ten (10)
Business Days after presentation of a bill and demand for payment therefor,
Owner may pay or deduct from the advances to be made any of such expenses and
any proceeds so applied shall be deemed advances under this Agreement, and
deducted from the total funds available to Agent under this Agreement.
Notwithstanding anything to the contrary contained in the foregoing, Agent shall
not be required to reimburse Owner for any of the foregoing obligations, costs
and expenses which constitute properly capitalizable costs under


                                       31
<PAGE>   33
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



generally accepted accounting principles. Expenses incurred by Owner (including,
without limitation, Financing Costs) in financing obligations, costs and
expenses pending allocation as a capitalized cost to a Unit shall be payable by
Agent hereunder, if not capitalized by Owner. Agent shall not be required to pay
any start-up costs associated with the commencement of operations at the Ammonia
Project or any related operating costs associated with the Ammonia Project,
which costs and expenses shall be borne by the Operator under the Operating
Agreement.

                  9.6 Certificates; Other Information. Agent shall furnish to
Owner:

                  (a) concurrently with the delivery of the financial statements
         referred to in subsection 9.6(b) hereof, a certificate of a Responsible
         Officer stating that, to the best of such Responsible Officer's
         knowledge, Agent during such period has observed or performed in all
         material respects all of its covenants and other agreements, and
         satisfied in all material respects every condition contained in this
         Agreement and in the Construction Documents to be observed, performed
         or satisfied by it, and that such Responsible Officer has obtained no
         knowledge of any Event of Default or Potential Default except as
         specified in such certificate;

                  (b) from time to time, (i) promptly upon their becoming
         available (but in any event, within 120 days after the end of each
         fiscal year with respect to annual statements and within 90 days after
         the end of each fiscal quarter with respect to quarterly statements),
         copies of the annual audited financial statements of the Guarantor and
         its consolidated subsidiaries and the quarterly unaudited financial
         statements (balance sheet, income statement and cash flow statement) of
         the Guarantor and its consolidated subsidiaries, (ii) promptly upon
         request, such other information with respect to Agent's or the
         Guarantor's operations, business, property, assets, financial condition
         or litigation as Owner shall reasonably request, (iii) promptly after a
         Responsible Officer of Agent obtains knowledge of any Event of Default
         or Potential Default or Event of Unit Termination or Potential Event of
         Unit Termination or Casualty Event, a certificate of a Responsible
         Officer of Agent specifying to the extent known the nature and period
         of existence of such Event of Default or Potential Default or Event of
         Unit Termination or Potential Event of Unit Termination or Casualty
         Event, and what action, if any, Agent has taken, is taking, or proposes
         to take with respect thereto and (iv) promptly after a Responsible
         Officer of Agent obtains knowledge of any material adverse change in
         the financial condition or business of Agent or the Guarantor or of any
         litigation of the type described in subsection 8.4 hereof, a
         certificate of a Responsible Officer of Agent describing such change or
         litigation as the case may be.

                  9.7 Conduct of Business and Maintenance of Existence. Agent
shall preserve, renew and keep in full force and effect its existence as a
limited partnership


                                       32
<PAGE>   34
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



(except as otherwise permitted herein), and take all reasonable action to
maintain all rights, privileges and franchises material to the conduct of its
business, and comply with all Legal Requirements; except any Legal Requirements,
the non-compliance with which, individually or in the aggregate, (i) will not
place either Owner or any Assignee in any danger of any monetary civil liability
which Owner or any Assignee is not adequately indemnified for (Agent's
obligations under Section 12 of this Agreement shall be deemed to be adequate
indemnification if no Event of Default exists) or any other material civil
liability or penalty or subject Owner or any Assignee to any criminal liability
as a result of a failure to comply therewith and (ii) will not result in a
material diminution in the value of any Unit Premises, Unit Improvements, Unit
FF&E or Unit or in any material risk of the loss, sale or forfeiture or loss of
use of any thereof; provided, however, that nothing contained in this subsection
9.7 shall prevent Agent from ceasing or omitting to exercise any rights,
privileges or franchises which in the reasonable judgment of Agent can no longer
be profitably exercised or prevent Agent from selling, abandoning or otherwise
disposing of any property, the retention of which in the reasonable judgment of
Agent is inadvisable in relation to the business of Agent, or prevent any
liquidation of any subsidiary of Agent, or any merger, consolidation or sale,
permitted by the provisions of subsection 10.2 hereof.

                  9.8 Notices. Agent shall give notice to Owner promptly upon
the occurrence of:

                  (a) any notice given by or to Agent pursuant to any of the
         Construction Documents that a default has occurred thereunder;

                  (b) any condition which results or is reasonably likely to
         result in a Force Majeure Delay in completion of the Unit Improvements
         that is reasonably likely to extend the Unit Completion Date (without
         taking into account any Force Majeure Delay);

                  (c) any "Event of Default" or "Potential Default" under the
         Lease; and

                  (d) notices received from the lessor under any Ground Lease.

Each notice pursuant to this subsection shall be accompanied by a statement of a
Responsible Officer setting forth details of the occurrence referred to therein
and stating what action, if any, Agent proposes to take with respect thereto.

                  9.9 Legal Requirements and Insurance Requirements. Agent shall
comply with every Insurance Requirement and Legal Requirement affecting (i) the
execution, delivery and performance of this Agreement and the Construction
Documents to which Agent is a party and (ii) any Unit Premises, Unit
Improvements, item of Unit FF&E or Unit, and Agent will not do or permit any act
or thing which is


                                       33
<PAGE>   35
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



contrary to any Insurance Requirement or which is contrary to any Legal
Requirement; except any Legal Requirements, the non-compliance with which,
individually or in the aggregate, (i) will not place either Owner or any
Assignee in any danger of any monetary civil liability which Owner or any
Assignee is not adequately indemnified for (Agent's obligations under Section 12
of this Agreement shall be deemed to be adequate indemnification if no Event of
Default exists) or any other material civil liability or penalty or subject
Owner or any Assignee to any criminal liability as a result of a failure to
comply therewith and (ii) will not result in a material diminution in the value
of any Unit Premises, Unit Improvements, Unit FF&E or Unit or in any material
risk of the loss, sale or forfeiture or loss of use of any thereof.

                  9.10 Payment of Taxes. With respect to any Unit Premises, Unit
Improvements, Unit FF&E or Unit, Agent shall make all required reports to the
appropriate taxing authorities and Owner shall capitalize and include as an
element of Unit Acquisition Cost of a Unit during the term of this Agreement the
taxes that Agent would be required to pay if such Unit Premises, Unit
Improvements or Unit was a Parcel of Property under paragraph (c) of Section 9
of the Lease.

                  9.11 Filings, Etc. Agent shall promptly and duly execute,
deliver, file, and record, all such documents, statements, filings, and
registrations, and take such further action as Owner or any Assignee shall from
time to time reasonably request and shall install such signs or other markings
as shall be required by any applicable Legal Requirement in order to establish,
perfect and maintain Owner's or any Assignee's title to and interest in any Unit
Premises, Unit Improvements, Unit FF&E and any Unit and any Assignee's interest
in this Agreement, any Unit Premises, Unit Improvements, Unit FF&E or any Unit
as against Agent or any third party in any applicable jurisdiction. All costs
and expenses arising out of Agent's obligations under this subsection 9.11 shall
be capitalized by Owner and included as an element of Unit Acquisition Cost of a
Unit.

                  9.12 Use of Proceeds. The proceeds of each advance shall be
used by Agent for payment of costs specified in the applicable request for the
advance and in accordance with the respective Unit Budget or to reimburse Agent
for any such costs paid by Agent.

                  9.13 Compliance with Other Requirements. Agent shall use every
commercially reasonable precaution to prevent loss or damage to any Unit
Premises, Unit Improvements, Unit FF&E, or any Unit and to prevent injury to
third Persons or property of third Persons. Agent shall cooperate fully with
Owner and any additional insured or loss payee and all insurance companies
providing insurance pursuant to subsection 9.3 hereof in the investigation and
defense of any claims or suits arising from the ownership or operation of
equipment or ownership, use, or occupancy of any Unit Premises, Unit
Improvements, Unit FF&E or any Unit and Owner and any Indemnified Person shall
comply, at the expense of Agent, with all reasonable requests


                                       34
<PAGE>   36
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



for assistance of Agent and any insurance companies in connection therewith;
provided that nothing contained in this subsection shall be construed as
imposing on Owner any duty to investigate or defend any such claims or suits.
Agent shall comply and shall use reasonable efforts to cause all Persons
operating equipment on, using or occupying any Unit Premises, Unit Improvements,
Unit FF&E, or any Unit to comply with every Insurance Requirement and Legal
Requirement regarding acquiring, titling, registering, leasing, subleasing,
insuring, using, occupying, operating and disposing of any Unit Premises, Unit
Improvements, Unit FF&E, or any Unit, and, if applicable, the licensing of
operators thereof; except any Legal Requirements, the non-compliance with which,
individually or in the aggregate, (i) will not place either Owner or any
Assignee in any danger of any monetary civil liability which Owner or any
Assignee is not adequately indemnified for (Agent's obligations under Section 12
of this Agreement shall be deemed to be adequate indemnification if no Event of
Default exists) or any other material civil liability or penalty or subject
Owner or any Assignee to any criminal liability as a result of a failure to
comply therewith and (ii) will not result in a material diminution in the value
of any Unit Premises, Unit Improvements, Unit FF&E or Unit or in any material
risk of the loss, sale or forfeiture or loss of use of any thereof.

                  9.14 Site Lease. Agent agrees to pay or cause to be paid, on
or before the first Business Day of each calendar year, all rent to be due under
the Site Lease for such calendar year.

                  9.15 Consent Agreements. Agent agrees to deliver to Owner and
Assignee, on or before the date that is one hundred twenty (120) days from the
date of this Agreement, an executed copy of each consent with respect to each of
the Assignment Agreements listed on Schedule I.

                  SECTION 10.       NEGATIVE COVENANTS

                  Agent hereby agrees that, so long as this Agreement remains in
effect, Agent shall not directly or indirectly:

                  10.1 Changes in Unit Plans or Unit Budget.

                  (a) Modify or supplement in any material respect any Unit
Plans or any Unit Budget without the prior written consent of Owner (which
consent will not be unreasonably withheld or delayed) and all Governmental
Authorities which previously have approved the matters to be changed, if the
effect of the failure to obtain such consent will, (i) place either Owner or any
Assignee in any danger of any monetary civil liability for which Owner or any
Assignee is not adequately indemnified for (Agent's obligations under Section 12
of this Agreement shall be deemed to be adequate indemnification if no Event of
Default exists) or any other material civil liability or penalty or subject
Owner or any Assignee to any criminal liability as a result of a


                                       35
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



failure to comply therewith, (ii) result in a material diminution in the value
of any Unit Premises, Unit Improvements, Unit FF&E or Unit or in any material
risk of the loss, sale or forfeiture or loss of use of any thereof, or (iii)
materially impair the ability of Agent to perform its obligations hereunder or
(b) receive advances with respect to a Unit which exceed the Unit Budget for
such Unit.

                  10.2 Prohibition of Fundamental Changes. Consolidate with or
merge into any other Person as such prohibition is set forth in Section 26 of
the Lease, except that the term "Owner" shall substitute for the term "the
Lessor" and the term "Agent" shall substitute for the term "the Lessee".

                  10.3 Acquire Fee or Leasehold Interest. Acquire a fee or
leasehold interest on behalf of Owner in any Unit Premises other than the
Project Parcel until Agent has delivered all documents required by Section 4
hereof and in the reasonable judgment of Owner satisfied the conditions set
forth in such Section 4.

                  10.4 Assignment of Obligations. Except as provided in
subsection 2.1 hereof, assign its obligations hereunder to any other party.

                  SECTION 11.       EVENTS OF DEFAULT, EVENTS OF UNIT
                                    TERMINATION AND CASUALTY EVENTS

                  11.1 Events of Default. The occurrence of any of the following
shall constitute an Event of Default:

                  (a) Failure to Make Payments. Failure of Agent to make any
         payment required by Section 11.2(e), 11.4(a), 11.6 or 19 hereof when
         due or failure by Agent to pay any other amount due hereunder for more
         than fifteen (15) days after written demand for such other payment.

                  (b) Unauthorized Assignments, Etc. Except as provided in
         subsection 2.1 hereof, assignment by Agent of any interest in this
         Agreement or any advance to be made hereunder or any interest in
         either.

                  (c) Misrepresentations. Any representation or warranty made or
         deemed made or certified to by Agent in this Agreement or any Operative
         Document or which is contained in any certificate, document or
         financial or other statement furnished under or in connection with this
         Agreement shall prove to have been false or inaccurate in any material
         respect on or as of the date made or deemed made.

                  (d) Involuntary Bankruptcy, Etc. The entry of a decree or
         order for relief in respect of Agent or the Guarantor by a court having
         jurisdiction in the premises, or the appointment of a receiver,
         liquidator, assignee, custodian,


                                       36
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         trustee, sequestrator (or other similar official) of Agent or the
         Guarantor or of any substantial part of Agent's or the Guarantor's
         property, or ordering the winding up or liquidation of Agent's or the
         Guarantor's affairs, in an involuntary case under the U.S. Federal
         Bankruptcy Code, as now or hereafter constituted, the Bankruptcy and
         Insolvency Act (Canada), as now or hereafter constituted, or any other
         applicable federal, state or provincial bankruptcy, insolvency,
         reorganization, composition or other similar law of any jurisdiction;
         or the commencement against Agent or the Guarantor of an involuntary
         case under the U.S. Federal Bankruptcy Code, as now or hereafter
         constituted, the Bankruptcy and Insolvency Act (Canada), as now or
         hereafter constituted, or any other applicable federal, state or
         provincial bankruptcy, insolvency, reorganization, composition or other
         similar law of any jurisdiction, and the continuance of any such case
         unstayed and in effect for a period of 60 consecutive days.

                  (e) Voluntary Bankruptcy, Etc. Entry or deemed entry of an
         order for relief in any case under the U.S. Federal Bankruptcy Code, as
         now or hereafter constituted or the Bankruptcy and Insolvency Act
         (Canada), as now or hereafter constituted, involving Agent or the
         Guarantor or the suspension or discontinuance of Agent's or the
         Guarantor's business operations, Agent's or the Guarantor's insolvency
         (however evidenced) or Agent's or the Guarantor's admission of
         insolvency or bankruptcy, or the commencement by Agent or the Guarantor
         of a voluntary case under the U.S. Federal Bankruptcy Code, as now or
         hereafter constituted, the Bankruptcy and Insolvency Act (Canada), or
         any other applicable federal, state or provincial bankruptcy,
         insolvency, reorganization, composition or other similar law of any
         jurisdiction, or the consent by Agent or the Guarantor to the
         appointment of or taking possession by a receiver, liquidator,
         assignee, custodian, trustee, sequestrator (or other similar official)
         of Agent or the Guarantor or of any substantial part of Agent's or the
         Guarantor's property, or the making by Agent or the Guarantor of an
         assignment for the benefit of creditors, or the failure of Agent or the
         Guarantor generally to pay its debts as such debts become due, or the
         taking of partnership or other action by or on behalf of Agent or the
         Guarantor in furtherance of any such action.

                  (f) Negative Covenants. Agent shall default in the performance
         or observance of any agreement, covenant or condition contained in
         Section 10 hereof.

                  (g) Other Defaults. Agent shall default in the performance or
         observance of any other term, covenant, condition or obligation
         contained in this Agreement or any other Operative Document (except a
         Ground Lease), and if such default is capable of cure, such default
         shall continue for thirty (30) days after written notice shall have
         been given to Agent by Owner specifying such


                                       37
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         default and requiring such default to be remedied; provided that, if
         such default is of a nature that it is capable of being cured, but not
         within such thirty (30) day period, and Agent shall have diligently
         commenced curing such default within such thirty (30) day period and
         Agent shall have proceeded diligently and in good faith thereafter to
         complete curing such default, such thirty (30) day period shall be
         extended to one hundred eighty (180) days; provided further that an
         Event of Unit Termination and a Casualty Event shall not constitute an
         Event of Default hereunder.

                  (h) Default under Lease. An Event of Default (as defined in
         the Lease) shall occur under the Lease or the Lease shall be terminated
         or otherwise cease to be in full force and effect.

                  (i) Payment of Obligations. An Event of Default (as defined in
         the PCS Term Credit Agreement) shall occur under the PCS Term Credit
         Agreement. Other than as disclosed in Schedule H to the PCS Term Credit
         Agreement, an event of default (after the expiry of all applicable
         grace periods) under any one or more agreements, indentures or
         instruments under which the Guarantor or any of its Material
         Subsidiaries has outstanding Debt in excess of Cdn. $40,000,000 or the
         U.S. Dollar Equivalent thereof shall happen and be continuing without
         being cured or discharged by repayment, or any Debt of the Guarantor or
         any of its Material Subsidiaries in excess of Cdn. $40,000,000 or the
         U.S. Dollar Equivalent thereof which is payable on demand is not paid
         on demand.

                  (j) Defaults under any Ground Lease. Agent shall fail to
         observe or perform, after the expiration of any applicable grace
         period, any material term, covenant or condition of any Ground Lease
         relating to a Unit Premises, to be observed or performed, unless any
         such observance or performance shall have been waived or not required
         by the landlord under such Ground Lease, or if any one or more of the
         events referred to in the Site lease, the Sublease or any Ground Lease
         shall occur which would cause the Site Lease, the Sublease or such
         Ground Lease to terminate without notice or action by the landlord
         thereunder or which would entitle the landlord under the Site Lease,
         the Sublease or such Ground Lease to terminate the Site Lease, the
         Sublease or such Ground Lease and the term thereof by the giving of
         notice to Owner without opportunity to cure, as tenant thereunder, or
         if any of the terms, covenants or conditions of the Site Lease, the
         Sublease or any Ground Lease shall in any manner be modified, changed,
         terminated, supplemented, altered or amended in any material respect
         without the consent of Owner and any Assignee.

                  (k) Gas Contract; Ancillary Facility Agreements; PCS Guaranty.
         The Gas Contract, any Ancillary Facility Agreement, the PCS Guaranty or
         any other Operative Document shall be modified, changed, terminated,


                                       38
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         supplemented, altered or amended in any material respect without the
         consent of Owner and Assignee.

                  (l) PCS Guaranty. (i) The PCS Guaranty ceases to be in full
         force and effect prior to the termination thereof in accordance with
         its terms, or (ii) the Guarantor defaults in the performance of any
         obligation or covenant contained in the PCS Guaranty, after required
         notice of such default shall have been given, and any applicable grace
         period shall have expired.

                  (m) Guarantor Representations. Any representation or warranty
         made by the Guarantor in the PCS Guaranty or in any document
         contemplated hereby or thereby proves to be false, misleading or
         inaccurate in any material respect on or as of the date made or deemed
         made.

                  (n) The Guarantor ceases to directly or indirectly own all of
         the outstanding partnership interests of Agent and issued and
         outstanding shares of the capital stock of PCS Nitrogen Fertilizer
         Operations, Inc.

                  11.2     Owner's Rights upon an Event of Default.

                  (a) Upon the occurrence and continuation of any Event of
Default Owner may, in addition to exercising any other rights and remedies
available to it under applicable law, do any one or more of the following (if,
within fifteen (15) Business Days of receipt by Agent of an Event of Default
Notice (as defined in Section 19 hereof), Agent has not made a request to
purchase all Unit Premises, Unit Improvements, Unit FF&E or Units under Section
19 or, if Agent has so made such a request but has not consummated within thirty
(30) Business Days of receipt of the Event of Default Notice such purchase in
full compliance with Section 19):

                  (i) Terminate this Agreement and/or Owner's obligations to
         make any further advances hereunder by written notice to Agent, subject
         to the maximum amount Owner shall be entitled to recover from Agent, as
         described in paragraph (f) of this subsection 11.2;

                  (ii) Take immediate possession of any Unit Premises, Unit
         Improvements, Unit FF&E and Unit and remove any equipment or property
         of Owner in the possession of Agent, wherever situated, and for such
         purpose, enter upon any Unit Premises, Unit Improvements or Unit
         without liability to Agent for so doing; provided that the taking of
         possession of any Unit Premises, Unit Improvements, Unit FF&E or Unit
         shall take place in a commercially reasonable manner;

                  (iii) Whether or not any action has been taken under (a)
         above, sell any Unit Premises, Unit Improvements, Unit FF&E or Unit
         (free of or subject


                                       39
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         to the rights of Agent or any other Person under this Agreement and
         with or without the concurrence or request of Agent);

                  (iv) Hold, use, occupy, operate, remove, lease, sublease or
         keep idle any Unit Premises, Unit Improvements, Unit FF&E or Unit as
         Owner in its sole discretion may determine, without any duty to account
         to Agent with respect to any such action or inaction, except that Owner
         agrees that any profit it derives from the occupation or use of any
         Unit Premises, Unit Improvements, Unit FF&E or Unit while exercising
         its rights under this subsection 11.2 will be applied to reduce the
         Accrued Default Obligations; and

                  (v) Exercise any other right or remedy which may be available
         under applicable law and in general proceed by appropriate judicial
         proceedings, either at law or in equity, to enforce the terms hereof or
         to recover damages for the breach hereof.

                  (b) Suit or suits for the recovery of any default in the
payment of any sum due hereunder or for damages may be brought by Owner from
time to time at Owner's election, and nothing herein contained shall be deemed
to require Owner to await the date whereon this Agreement or the term hereof
would have expired by limitation had there been no such default by Agent or no
such termination or cancellation.

                  (c) The receipt of any payments under this Agreement by Owner
with knowledge of any breach of this Agreement by Agent or of any default by
Agent in the performance of any of the terms, covenants or conditions of this
Agreement, shall not be deemed to be a waiver of any provision of this
Agreement.

                  (d) No receipt of moneys by Owner from Agent after the
termination or cancellation hereof in any lawful manner shall reinstate or
continue this Agreement, or operate as a waiver of the right of Owner to recover
possession of any Unit Premises, Unit Improvements, Unit FF&E or Unit by proper
suit, action, proceedings or remedy or operate as a waiver of the right to
receive any and all amounts owing by Agent to or on behalf of Owner hereunder;
it being agreed that, after the service of notice to terminate or cancel this
Agreement, and the expiration of the time therein specified, if the default has
not been cured in the meantime, or after the commencement of suit, action or
summary proceedings or of any other remedy, or after a final order, warrant or
judgment for the possession of any Unit Premises, Unit Improvements, Unit FF&E
or Unit, Owner may demand, receive and collect any moneys payable hereunder,
without in any manner affecting such notice, proceedings, suit, action, order,
warrant or judgment; and any and all such moneys so collected shall be deemed to
be payments on account for the use, operation and occupation of the Unit
Premises, Unit Improvements, Unit FF&E or Unit, or at the election of Owner, on
account of


                                       40
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



Agent's liability hereunder and will be applied to reduce the Accrued Default
Obligations.

                  (e) Agent hereby expressly confirms that, in any event,
including after any Event of Default, and notwithstanding any termination of
this Agreement or reentry or repossession by Owner, Agent shall be liable for,
and Owner may recover from Agent, (i) all of Owner's obligations, costs and
expenses incurred in good faith in connection with its obligations under this
Agreement and for which Owner may demand reimbursement pursuant to subsection
9.5 hereof, (ii) all amounts payable hereunder or under any other Operative
Document and (iii) all losses, damages, costs and expenses (including, without
limitation, reasonable attorneys' fees and expenses, commissions, filing fees
and sales or transfer taxes) sustained by Owner by reason of such Event of
Default and the exercise of Owner's remedies with respect thereto, including, in
the event of a sale by Owner of any Unit Premises, Unit Improvements, Unit FF&E
or Unit pursuant to this subsection 11.2, all costs and expenses associated with
such sale. The amounts payable in clauses (i) through (iii) above are
hereinafter sometimes referred to as the "Accrued Default Obligations". Accrued
Default Obligations shall not include any damages for loss of profits arising
from the prospective use, operation and occupancy by parties other than Agent of
any Unit Premises, Unit Improvements, Unit FF&E or Unit or the anticipated
receipt of income therefrom subsequent to Agent's possession of such Unit
Premises, Unit Improvements, Unit FF&E or Unit.

                  (f) After an Event of Default, Owner may sell its interest in
any Unit Premises, Unit Improvements, Unit FF&E and Unit in any commercially
reasonable manner upon any terms that Owner deems satisfactory, free of any
rights of Agent or any Person claiming through or under Agent. In the event of
any such sale, or in the event Owner elects not to sell any Unit Premises, Unit
Improvements, Unit FF&E or Unit, in addition to the Accrued Default Obligations,
Owner shall be entitled to recover from Agent, as liquidated damages, and not as
a penalty, an amount equal to eighty-five percent (85%) of the Unit Acquisition
Cost of any Unit Premises, Unit Improvements, Unit FF&E and Units under this
Agreement. Proceeds of any such sale received by Owner, or, in the event Owner
elects not to sell, proceeds at any time thereafter received by Owner from any
sale, occupation, operation, use or lease of any Unit Premises, Unit
Improvements, Unit FF&E or Unit (net of all reasonable costs and expenses
incurred by Owner in connection with any sale, occupation, operation, use or
lease of any Unit Premises, Unit Improvements, Unit FF&E or Unit) in excess of
fifteen percent (15%) of the Unit Acquisition Cost of such Unit Premises, Unit
Improvements, Unit FF&E or Unit, shall be credited against the Accrued Default
Obligations Agent is required to pay under this subsection 11.2. If such excess
proceeds exceed the Accrued Default Obligations, or, if Agent has paid all
amounts required to be paid under this subsection 11.2, such excess shall be
paid by Owner to Agent. If Agent converts any such Unit Premises, Unit
Improvements, Unit FF&E or Unit after an Event of Default, or if such Unit
Premises, Unit Improvements, Unit FF&E or Unit is lost or destroyed, in addition
to the Accrued Default Obligations,


                                       41
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



Owner may cause such Agent to pay to Owner, and Agent shall pay to Owner, as
liquidated damages and not as a penalty, an amount equal to eighty-five percent
(85%) of the Unit Acquisition Cost of such Unit Premises, Unit Improvements,
Unit FF&E or Unit.

                  (g) In the event of a sale pursuant to this subsection 11.2,
upon receipt by Owner of the amounts payable hereunder, Owner shall transfer all
of Owner's right, title and interest in and to the Unit Premises, Unit
Improvements, Unit FF&E and Unit to the purchaser thereof.

                  (h) In addition to its other rights in this subsection 11.2,
Owner may exercise its various rights under the Operating Agreement, the Gas
Contract, the Ancillary Facility Agreements or any Construction Agreement or
transfer such rights to the purchaser in a sale.

                  (i) No remedy referred to in this subsection 11.2 is intended
to be exclusive, but each shall be cumulative and in addition to any other
remedy referred to above or otherwise available to Owner at law or in equity,
and the exercise in whole or in part by Owner of any one or more of such
remedies shall not preclude the simultaneous or later exercise by Owner of any
or all such other remedies. No waiver by Owner of any Event of Default hereunder
shall in any way be, or be construed to be, a waiver of any future or subsequent
Event of Default.

                  11.3 Events of Unit Termination. The occurrence of any of the
following shall constitute an Event of Unit Termination with respect to a Unit:

                  (a) Nonconforming Work. If the construction of the Unit
         Improvements, or any part thereof, deviates from the Unit Plans and
         results in a material diminution in the value of any Unit Premises,
         Unit Improvements, Unit FF&E or Unit or there shall be any structural
         defect in any Unit Improvement and Agent fails to correct such
         nonconforming work or structural defect in a reasonably prompt and
         satisfactory fashion after notice and demand by Owner.

                  (b) Failure to Complete. If as of the close of business on a
         Unit Completion Date the related Unit Improvements have not for
         whatever reason (including an event of force majeure deferring
         completion beyond the Force Majeure Delay) been completed as herein
         provided, or if the Certificate of Substantial Completion and AFL Unit
         Leasing Record have not been executed and delivered by the respective
         Unit Completion Date, or if Owner shall reasonably determine during the
         course of construction that the Unit Improvements cannot for whatever
         reason (including an event of force majeure deferring completion beyond
         the Force Majeure Delay) be completed by the Unit Completion Date.


                                       42
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  (c) Unsatisfactory Title. If at any time title to the Ammonia
         Project or any other Unit is not reasonably satisfactory to Owner by
         reason of any Lien, encumbrance, or other environmental defect
         affecting title, except for Permitted Liens, and such Lien, encumbrance
         or other defect is not corrected by and at the expense of Agent within
         ninety (90) days after notice to Agent.

                  (d) Other Security Agreements. If (i) Agent executes any
         chattel mortgage or other security agreement on any materials, fixtures
         or articles of personal property used in the construction or operation
         of the Unit Improvements or if any such materials, fixtures or articles
         are purchased pursuant to any conditional sales contract or other
         security agreement or otherwise so that the title thereto will not vest
         in Owner free from encumbrance or (ii) Agent does not furnish to Owner
         upon request the contracts, bills of sale, statements, receipted
         vouchers and other agreements and documents, or any of them, under
         which Owner claims title to such materials, fixtures or articles.

                  (e) Permits. If Agent shall fail in respect of the Ammonia
         Project to obtain or be unable to obtain any material Permit, or if any
         Permit shall be revoked or otherwise cease to be in full force and
         effect unless, if such revocation or cessation shall not be due to
         Agent's negligence or willful misconduct, Agent shall have obtained
         reinstatement or reissuance of such Permit within thirty (30) days
         after the revocation or expiration thereof, or if such reinstatement or
         reissuance is of a nature that it cannot be completely effected within
         thirty (30) days, Agent shall have diligently commenced application for
         such reinstatement or reissuance and shall thereafter be diligently
         proceeding to complete said reinstatement or reissuance.

                  11.4     Owner's Rights upon Event of Unit Termination.

                  (a) If any Event of Unit Termination with respect to a Unit
shall occur, Owner shall have no further obligation to make advances to Agent
with respect to such Unit, and Agent shall, upon written notice by Owner of such
Event of Unit Termination, either (i) purchase such Unit within ninety (90) days
after written notice by Owner of such Event of Unit Termination at a price equal
to the Unit Acquisition Cost for such Unit, or (ii) pay to Owner, within five
(5) Business Days of Owner's written notice of such Event of Unit Termination
(the "Surrender Date"), an amount equal to 89.9% of the Unit Acquisition Cost of
such Unit and to be subject to the requirements of paragraph (b) of this
subsection 11.4. In the event Agent elects to purchase such Unit from Owner, at
the time of such sale, Agent shall be required, in addition to its obligation to
pay all amounts contemplated by subsection 9.5 hereof, to pay to Owner Owner's
obligations, costs, losses, damages, and expenses (including, without
limitation, taxes and reasonable attorneys' fees and expenses) sustained by
Owner in good faith by reason of such Event of Unit Termination and exercise of
Owner's rights under this subsection 11.4.


                                       43
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  (b) In the event Agent elects to proceed under clause (ii) of
subsection 11.4(a) and makes the payment contemplated thereby, Owner may sell
such Unit to a third party and Agent shall have no further right, claim or
interest in such Unit. If Owner shall fail to sell such Unit within seven (7)
days of the Surrender Date, the Assignee shall have the right, but not the
obligation, to sell such Unit to a third party. The proceeds of sale received by
Owner or such Assignee, as the case may be, from any sale of such Unit shall be
retained by Owner or such Assignee, as the case may be, provided that if the
proceeds of sale exceed 10.1% of the Unit Acquisition Cost of such Unit, such
excess shall be paid by Owner or such Assignee, as the case may be, to Agent net
of all amounts to be paid by Agent to Owner pursuant to the last sentence of
subsection 11.4(a) hereof.

                  11.5 Casualty Events. The occurrence of any of the following
shall constitute a Casualty Event with respect to a Unit:

                  (a) Damage or Destruction. If any Unit Improvements are
partially or totally damaged or destroyed by fire or any other cause and the
restoration thereof cannot reasonably be expected to be completed so that the
Unit Improvements will be completed on or before the applicable Unit Completion
Date, subject to any Force Majeure Delay.

                  (b) Takings. If the use, occupancy or title to any Unit is
taken, requisitioned or sold in, by or on account of actual or threatened
eminent domain or confiscation or similar proceedings or other action by any
Governmental Authority (such events collectively referred to as a "Taking") and
such Taking affects a substantial portion of a Unit. Upon receipt of proceeds
from any award or sale made in connection with such Taking, so long as no Event
of Default or Potential Default has occurred and is continuing, and so long as
Agent has made all payments to Owner required under subsection 11.6 hereof,
Owner shall remit to Agent the net amount of such proceeds remaining after
reimbursement for all costs and expenses (including, without limitation,
reasonable attorneys' fees) incurred by Owner in connection with the negotiation
and settlement of any proceedings related to such Taking. If such proceeds are
received prior to Agent making the payments required under subsection 11.6
hereof, the net proceeds shall be applied to the amount payable thereunder. A
Taking shall be deemed "to affect a substantial portion" of a Unit if after such
Taking such Unit is, or will be, in Agent's reasonable judgment, unusable for
Agent's ordinary business purposes.

                  11.6 Owner's Rights upon the occurrence of a Casualty Event.
If any Casualty Event shall occur, (i) Agent shall promptly notify Owner in
writing of such event, (ii) on a date designated by Agent, which shall be a date
within ninety (90) days following such event, Agent shall pay to Owner an amount
equal to eighty-five percent (85%) of the Unit Acquisition Cost of such Unit and
(iii) Agent shall be required, in addition to its obligation to pay all amounts
contemplated by subsection 9.5 hereof, to


                                       44
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                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



pay to Owner Owner's obligations, costs, losses, damages, and expenses
(including, without limitation, taxes and reasonable attorneys' fees and
expenses) sustained by Owner by reason of such Casualty Event and exercise of
Owner's rights under this subsection 11.6. Insurance and condemnation proceeds,
if any, received by Owner that, together with the amounts paid by Agent to Owner
pursuant to clause (ii) of the preceding sentence, exceed the Unit Acquisition
Cost of such Unit, shall be paid by Owner to Agent upon payment by Agent of all
amounts referred to in clause (iii) of the preceding sentence.

                  SECTION 12.       INDEMNITIES

                  (a) Agent shall, and hereby does, indemnify and hold harmless
Owner, Merrill Lynch, Merrill Leasing, any Assignee, any successor or successors
and any Affiliate of each of them, and their respective officers, directors,
incorporators, shareholders, partners (general and limited, including, without
limitation, the general and limited partners of Owner), employees, agents and
servants (each of the foregoing an "Indemnified Person") from and against all
liabilities (including, without limitation, strict liability in tort and
environmental law), taxes, losses, obligations, claims (including, without
limitation, strict liability in tort), damages, penalties, causes of action,
suits, costs and expenses (including, without limitation, reasonable attorneys'
and accountants' fees and expenses) or judgments of any nature relating to or in
any way arising out of:

                           (i) The Operative Documents and the transactions
                  contemplated thereby and the ordering, delivery, assembly,
                  installation, acquisition, construction (including, without
                  limitation, all obligations of Owner under any Construction
                  Agreement), title on acquisition, rejection, installation,
                  possession, titling, retitling, registration, reregistration,
                  custody by Agent of title and registration documents,
                  ownership, use, non-use, misuse, financing (including, without
                  limitation, all obligations of Owner under or in respect of
                  any interest rate swap, cap, collar or other financial hedging
                  arrangement and any amounts payable by Owner under any such
                  arrangement to reduce the notional amount thereof by the
                  amount of any prepayment of any borrowing to which such
                  interest rate swap, cap, collar or other financial hedging
                  arrangement relates), lease, sublease, refinancing, operation,
                  transportation, repair, return, redelivery or control of any
                  Unit Premises, Unit Improvements, Unit FF&E or Unit, or the
                  release of hazardous substances on, under, to or from, or the
                  generation or transportation of hazardous substances to or
                  from, any Unit Premises except (x) to the extent that such
                  costs are included in the Unit Acquisition Cost of such Unit
                  Premises, Unit Improvements, Unit FF&E or Unit, (y) for any
                  general administrative expenses of Owner, and (z) for the
                  income taxes


                                       45
<PAGE>   47
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  with respect to which indemnification is excluded under
                  paragraph (c) of Section 11 of the Lease; and

                           (ii) Any of the claims, demands, fees, taxes,
                  violations of contract, or any other matter or situation
                  described in or contemplated by the indemnification provisions
                  of subparagraphs (b), (c) and (d) of Section 11 of the Lease,
                  except that this Agreement shall substitute the terms "Owner"
                  for "the Lessor", "Agent" for "the Lessee", "this Agreement"
                  for "this Lease", and shall substitute the phrase "Unit
                  Premises, Unit Improvements, Unit FF&E or Unit" for the phrase
                  "Property or Equipment."

                  (b) The indemnification required under this Section 12 shall
be upon the terms provided in the paragraphs of Section 11 of the Lease
following paragraph (d) thereof, except that this Agreement shall substitute the
terms in the same manner as described in subparagraph (a)(ii) above.

                  SECTION 13.       LEASEHOLD INTERESTS

                  The provisions of Section 28 of the Lease shall govern each
Ground Lease hereunder, including without limitation the Site Lease, the
Sublease and each additional lease under which a leasehold interest in a Unit
Premises is subleased to Agent or an Affiliate of Agent hereunder, except this
Agreement shall substitute the terms "Owner" for "the Lessor", "Agent" for "the
Lessee", "Unit Premises, Unit Improvements, Unit FF&E and Unit" for "Parcel of
Property" and "Section 13" for "Section 28".

                  SECTION 14.       PURCHASES

                  In connection with, and as a condition to, the purchase of any
Unit Premises, Unit Improvements, Unit FF&E or Unit pursuant hereto, (i) Agent
shall pay at the time of purchase, in addition to the Unit Acquisition Cost and
all other amounts payable by Agent under this Agreement, and without limitation
of any of its obligations hereunder or under any other Operative Document, all
transfer taxes, transfer gains taxes, mortgage recording tax, if any, recording
and filing fees and all other similar taxes, fees, expenses and closing costs
(including reasonable attorneys' fees) in connection with the conveyance of such
Unit Premises, Unit Improvements, Unit FF&E or Unit to Agent and all other
amounts owing hereunder, and (ii) when Owner transfers title, such transfer
shall be on an as-is, non-installment sale basis, without warranty by, or
recourse to, Owner, except that such title shall be free of any Liens resulting
from Owner's willful or knowing act or omission not contemplated by this
Agreement, the Lease or the transactions contemplated thereby.


                                       46
<PAGE>   48
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  SECTION 15.       CHARACTER OF AMMONIA PROJECT

                  It is the intention of Owner and Agent that the components of
the Ammonia Project identified as personal property components in Exhibit J
hereto maintain their character as personal property for commercial law
purposes. Agent shall take all reasonable action to maintain such character and
shall obtain and record such instruments and take such steps as may be necessary
to prevent any Person from acquiring any rights in such components by reason of
such components being deemed to be real property.

                  SECTION 16.       PERMITTED CONTESTS

                  (a) Agent shall not be required, nor shall Owner have the
right, to pay, discharge or remove any tax, assessment, levy, fee, rent, charge,
Lien or encumbrance, or to comply or cause any Unit Premises, Unit Improvements
item of Unit FF&E or Unit to comply with any Legal Requirement applicable to any
Unit Premises, Unit Improvements item of Unit FF&E or Unit or the occupancy, use
or operation thereof, so long as no Event of Default exists under this
Agreement, and, in the judgment of Agent's counsel, Agent shall have reasonable
grounds to contest the existence, amount, applicability or validity thereof by
appropriate proceedings, which proceedings in the reasonable judgment of Owner,
(i) shall not involve any material danger that any Unit Premises, Unit
Improvements, item of Unit FF&E or Unit would be subject to sale, forfeiture,
loss or loss of use as a result of failure to comply therewith, (ii) shall not
affect the payment of any sums due and payable hereunder or result in any such
sums being payable to any Person other than Owner or any Assignee, (iii) will
not place Owner in any danger of any monetary civil liability which is not
adequately indemnified (Agent's obligations under Section 12 of this Agreement
shall be deemed to be adequate indemnification if no Event of Default exists) or
any other material civil liability or penalty or to any criminal liability, (iv)
if involving taxes, shall suspend the collection of the taxes, and (v) shall be
permitted under and be conducted in accordance with the provisions of any other
instrument to which Agent or any Unit Premises, Unit Improvements, item of Unit
FF&E, or Unit is subject and shall not constitute a default thereunder (the
"Permitted Contest"). Agent shall conduct all Permitted Contests in good faith
and with due diligence and shall promptly after the final determination
(including appeals) of any Permitted Contest, pay and discharge all amounts
which shall be determined to be payable therein. Owner shall at Agent's expense
cooperate in good faith with Agent with respect to all Permitted Contests
conducted by Agent pursuant to this Section 16, including without limitation in
assisting in the preparation of, and participating in, filings related to such
Permitted Contests.

                  (b) At least ten (10) days prior to the commencement of any
Permitted Contest, Agent shall notify Owner in writing thereof if the amount in
contest exceeds $1,000,000, and shall describe such proceeding in reasonable
detail. In the event that a taxing authority or subdivision thereof proposes an
additional assessment or


                                       47
<PAGE>   49
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



levy of any tax for which Agent is obligated to reimburse Owner under this
Agreement, or in the event that Owner is notified of the commencement of an
audit or similar proceeding which could result in such an additional assessment,
then Owner shall in a timely manner notify Agent in writing of such proposed
levy or proceeding.

                  (c) Owner and Agent agree that no Event of Default, Potential
Default, Event of Unit Termination or Potential Event of Unit Termination shall
be deemed to have occurred if the existence of the event causing such Event of
Default, Potential Default, Event of Unit Termination or Potential Event of Unit
Termination, as the case may be, is being contested by Agent as a Permitted
Contest in accordance with the terms of this Section 16.

                  SECTION 17.       SALE OR ASSIGNMENT BY OWNER

                  (a) Owner shall have the right to obtain equity and debt
financing for the acquisition and ownership of any Unit Premises, Unit
Improvements, Unit FF&E and Unit by selling or assigning its right, title and
interest in any or all amounts due from Agent or any third Person under this
Agreement; provided that any such sale or assignment shall be subject to the
rights and interests of Agent under this Agreement.

                  (b) Any Assignee shall, except as otherwise agreed by Owner
and Assignee, have (to the exclusion of Owner) all the rights, powers,
privileges and remedies of Owner hereunder, and Agent's obligations as between
itself and such Assignee hereunder shall not be subject to any claims or defense
that Agent may have against Owner, other than the defense of payment or
satisfaction of the obligation; provided that the foregoing shall not be deemed
to be a waiver of any claims Agent may have against Owner. Upon written notice
to Agent of any such assignment, Agent shall thereafter make payments of any and
all sums due hereunder to Assignee, to the extent specified in such written
notice, and only such payments to the applicable Assignee shall discharge the
obligation of Agent hereunder and only to the extent of such payments. Anything
contained herein to the contrary notwithstanding, no Assignee shall be obligated
to perform any duty, covenant or condition required to be performed by Owner
hereunder, and any such duty, covenant or condition shall be and remain the sole
obligation of Owner.

                  SECTION 18.       GENERAL CONDITIONS

                  The following conditions shall be applicable throughout the
term of this Agreement:

                  18.1 Survival. All indemnities, representations and warranties
and the obligation to pay Additional Rent (as defined in the Lease) shall
survive the expiration or other termination hereof.


                                       48
<PAGE>   50
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  18.2 No Waivers. No advance hereunder shall constitute a
waiver of any of the conditions of Owner's obligation to make further advances
nor, in the event Agent is unable to satisfy any such condition, shall any
waiver of such condition have the effect of precluding Owner from thereafter
declaring such inability to be an Event of Default as herein provided. Any
advance made by Owner and any sums expended by Owner pursuant to this Agreement
shall be deemed to have been made pursuant to this Agreement, notwithstanding
the existence of an uncured Event of Default. No advance at a time when an Event
of Default exists shall constitute a waiver of any right or remedy of Owner
existing by reason of such Event of Default, including, without limitation, the
right to refuse to make further advances.

                  18.3 Owner and Assignee Sole Beneficiaries. All conditions of
the obligation of Owner to make advances hereunder are imposed solely and
exclusively for the benefit of Owner and Assignee and their assigns and no other
Person shall have standing to require satisfaction of such conditions in
accordance with their terms or be entitled to assume that Owner will refuse to
make advances in the absence of strict compliance with any or all thereof and no
other Person shall, under any circumstances, be deemed to be a beneficiary of
such conditions, any or all of which may be freely waived in whole or in part by
Owner, with the consent of Assignee, at any time if in its sole discretion, it
deems it advisable to do so. Inspections and approvals of any Unit Plans, Unit
Premises, Unit Improvements, Unit FF&E, and Unit and the workmanship and
materials used therein impose no responsibility or liability of any nature
whatsoever on Owner, and no Person shall, under any circumstances, be entitled
to rely upon such inspections and approvals by Owner for any reason.

                  18.4 No Offsets, Etc. The obligations of Agent to pay all
amounts payable pursuant to this Agreement shall be absolute and unconditional
under any and all circumstances of any character (including, without limitation,
the circumstances set forth in clauses (A) through (K) below), and such amounts
shall be paid without notice, demand, defense (except the defense of prior
payment), setoff, deduction or counterclaim and without abatement, suspension,
deferment, diminution or reduction of any kind whatsoever, except as herein
expressly otherwise provided. Without limitation of the foregoing, the
obligation of Agent to lease and pay Basic Rent (as defined in the Lease) for a
Unit upon Substantial Completion is without any warranty or representation,
express or implied, as to any matter whatsoever on the part of Owner or any
Assignee or any Affiliate of either, or anyone acting on behalf of any of them.

                  AGENT HAS SELECTED AND SHALL SELECT ALL UNIT PREMISES, UNIT
IMPROVEMENTS, UNITS AND ITEMS OF UNIT FF&E CONSTRUCTED, ACQUIRED OR ORDERED ON
THE BASIS OF ITS OWN JUDGMENT. NEITHER OWNER NOR ANY ASSIGNEE NOR ANY AFFILIATE
OF EITHER, NOR ANYONE ACTING ON BEHALF OF ANY OF THEM, MAKES ANY REPRESENTATION
OR WARRANTY OF ANY KIND WHATSOEVER, EXPRESS OR IMPLIED, INCLUDING, WITHOUT
LIMITATION, AS TO THE


                                       49
<PAGE>   51
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



SAFETY, TITLE, CONDITION, QUALITY, QUANTITY, FITNESS FOR USE, MERCHANTABILITY,
CONFORMITY TO SPECIFICATION, OR ANY OTHER CHARACTERISTIC, OF ANY UNIT PREMISES,
UNIT IMPROVEMENTS, UNIT OR ITEM OF UNIT FF&E, OR AS TO WHETHER ANY UNIT
PREMISES, UNIT IMPROVEMENTS, UNIT OR ITEM OF UNIT FF&E OR THE OWNERSHIP, USE,
OCCUPANCY OR POSSESSION THEREOF COMPLIES WITH ANY LAWS, RULES, REGULATIONS OR
REQUIREMENTS OF ANY KIND.

                  AS BETWEEN OWNER AND AGENT, ANY ASSIGNEE OR ANY INDEMNIFIED
PERSON, AGENT WAIVES ANY AND ALL DEFENSES (EXCEPT THE DEFENSE OF FINAL AND
INDEFEASIBLE PRIOR PAYMENT), SET-OFFS, DEDUCTIONS, COUNTERCLAIMS (OTHER THAN
COMPULSORY COUNTERCLAIMS) (OR OTHER RIGHTS), EXISTING OR FUTURE, TO ITS
OBLIGATION TO PAY ALL AMOUNTS PAYABLE HEREUNDER, INCLUDING, WITHOUT LIMITATION,
ANY RELATING TO:

                  (A) THE SAFETY, TITLE, CONDITION, QUALITY, QUANTITY, FITNESS
FOR USE, MERCHANTABILITY, CONFORMITY TO SPECIFICATION, OR ANY OTHER QUALITY OR
CHARACTERISTIC OF ANY UNIT PREMISES, UNIT IMPROVEMENTS, UNIT OR ITEM OF UNIT
FF&E, LATENT OR NOT;

                  (B) ANY SET-OFF, COUNTERCLAIM (OTHER THAN COMPULSORY
COUNTERCLAIMS), RECOUPMENT, ABATEMENT, DEFENSE (EXCEPT THE DEFENSE OF FINAL AND
INDEFEASIBLE PRIOR PAYMENT) OR OTHER RIGHT WHICH AGENT MAY HAVE AGAINST OWNER,
ANY ASSIGNEE, OR ANY INDEMNIFIED PERSON FOR ANY REASON WHATSOEVER ARISING OUT OF
THIS OR ANY OTHER TRANSACTION OR MATTER;

                  (C) ANY DEFECT IN TITLE OR OWNERSHIP OF ANY UNIT PREMISES,
UNIT IMPROVEMENTS, OR UNIT OR ANY TITLE ENCUMBRANCE NOW OR HEREAFTER EXISTING
WITH RESPECT TO THE UNIT PREMISES, UNIT IMPROVEMENTS, UNIT OR ITEM OF UNIT FF&E;

                  (D) ANY FAILURE OR DELAY IN DELIVERY OR ANY LOSS, THEFT OR
DESTRUCTION OF, OR DAMAGE TO, ANY UNIT PREMISES, UNIT IMPROVEMENTS, UNIT OR ITEM
OF UNIT FF&E IN WHOLE OR IN PART, OR CESSATION OF THE USE OR POSSESSION OF ANY
UNIT PREMISES, UNIT IMPROVEMENTS, UNIT OR ITEM OF UNIT FF&E BY AGENT FOR ANY
REASON WHATSOEVER AND OF WHATEVER DURATION, OR ANY CONDEMNATION, CONFISCATION,
REQUISITION, SEIZURE, PURCHASE, TAKING OR FORFEITURE OF ANY UNIT PREMISES, UNIT
IMPROVEMENTS, UNIT OR ITEM OF UNIT FF&E IN WHOLE OR IN PART;


                                       50
<PAGE>   52
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  (E) ANY INABILITY OR ILLEGALITY WITH RESPECT TO THE USE,
OWNERSHIP, OCCUPANCY OR POSSESSION OF THE UNIT PREMISES, UNIT IMPROVEMENTS, UNIT
OR ITEMS OF UNIT FF&E BY AGENT;

                  (F) ANY INSOLVENCY, BANKRUPTCY, REORGANIZATION OR SIMILAR
PROCEEDING BY OR AGAINST AGENT OR OWNER OR ANY ASSIGNEE;

                  (G) ANY FAILURE TO OBTAIN, OR EXPIRATION, SUSPENSION OR OTHER
TERMINATION OF, OR INTERRUPTION TO, ANY REQUIRED LICENSES, PERMITS, CONSENTS,
AUTHORIZATIONS, APPROVALS OR OTHER LEGAL REQUIREMENTS RELATING TO THE
TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT;

                  (H) THE INVALIDITY OR UNENFORCEABILITY OF THIS AGREEMENT OR
ANY OTHER INFIRMITY HEREIN OR ANY LACK OF POWER OR AUTHORITY OF OWNER OR AGENT
TO ENTER INTO THIS AGREEMENT;

                  (I) ANY RESTRICTION ON THE EXCHANGE OF THE CURRENCY OF THE
REPUBLIC OF TRINIDAD AND TOBAGO INTO U.S. DOLLARS OR THE TRANSFER OF FUNDS TO
THE UNITED STATES;

                  (J) AGENT OR ANY OTHER PERSON AT ANY TIME HAVING IMMUNITY FROM
SUIT, PREJUDGMENT, ATTACHMENT, ATTACHMENT IN AID OF EXECUTION OR EXECUTION ON
THE GROUNDS OF SOVEREIGNTY OR OTHERWISE; OR

                  (K) ANY OTHER CIRCUMSTANCES OR HAPPENING WHATSOEVER RELATING
TO THE TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT, WHETHER OR NOT SIMILAR TO
ANY OF THE FOREGOING.

                  AGENT HEREBY WAIVES, TO THE EXTENT PERMITTED BY APPLICABLE
LAW, ANY AND ALL RIGHTS WHICH IT MAY NOW HAVE OR WHICH AT ANY TIME HEREAFTER MAY
BE CONFERRED UPON IT, BY STATUTE OR OTHERWISE, TO TERMINATE, CANCEL, QUIT,
RESCIND OR SURRENDER THIS AGREEMENT EXCEPT IN ACCORDANCE WITH THE EXPRESS TERMS
HEREOF. The making of payments under this agreement by Agent (including without
limitation payments pursuant to Section 12 hereof) shall not be deemed to be a
waiver of any claim or claims that Agent may in a separate action assert against
Owner or any other Person. Owner agrees to repay Agent amounts paid to Owner to
the extent such payments were in error and are not required by any of the terms
and provisions of this Agreement.


                                       51
<PAGE>   53
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  18.5     No Recourse.

                  (a) Owner's obligations hereunder are intended to be the
obligations of a limited partnership and of the corporation which is the general
partner thereof only and no recourse for the payment of any amount due under
this Agreement or any other Operative Document, or for any claim based thereon
or otherwise in respect thereof, shall be had against any limited partner of
Owner or any incorporator, shareholder, officer, director or Affiliate, as such,
past, present or future, of such corporate general partner or of any corporate
limited partner or of any successor corporation to such corporate general
partner or any corporate limited partner of Owner, or against any direct or
indirect parent corporation of such corporate general partner or of any limited
partner of Owner or any other subsidiary or Affiliate or any such direct or
indirect parent corporation or any incorporator, shareholder, officer or
director, as such, past, present or future, of any such parent or other
subsidiary or Affiliate, it being understood that Owner is a limited partnership
formed for the purpose of the transactions involved in and relating to this
Agreement, the Lease and the Operative Documents on the express understanding
aforesaid. Nothing contained in this subsection 18.5(a) shall be construed to
limit the exercise or enforcement, in accordance with the terms of this
Agreement, the Lease and the Operative Documents and any other documents
referred to herein, of rights and remedies against the limited partnership or
the corporate general partner of Owner or the assets of the limited partnership
or the corporate general partner of Owner.

                  (b) Agent's obligations hereunder are intended to be the
obligations of a limited partnership and of the corporation which is the general
partner thereof only and no recourse for any obligation of Agent hereunder, or
for any claim based thereon or otherwise in respect thereof, shall be had
against any limited partner of Agent or any incorporator, shareholder, officer
or director, or Affiliate, as such, past, present or future of such corporate
general partner or limited partner or of any successor corporation to such
corporate general partner or any corporate limited partner of Agent, or against
any direct or indirect parent corporation of such corporate general partner or
of any limited partner of Agent or any other subsidiary or Affiliate of any such
direct or indirect parent corporation or any incorporator, shareholder, officer
or director, as such, past, present or future, of any such parent or other
subsidiary or Affiliate. Nothing contained in this subsection 18.5(b) shall be
construed to limit the exercise or enforcement, in accordance with the terms of
this Agreement, the Lease, the PCS Guaranty and the Operative Documents and any
other documents referred to herein, of rights and remedies against (i) Agent or
the corporate general partner of Agent or the assets of Agent or the corporate
general partner of Agent or (ii) the Guarantor for obligations under the PCS
Guaranty.


                                       52
<PAGE>   54
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  18.6     Notices.

                  (a) All notices, offers, acceptances, approvals, waivers,
requests, demands and other communications hereunder or under any other
instrument, certificate or other document delivered in connection with the
transactions described herein shall be in writing, shall be addressed as
provided below and shall be considered as properly given (i) if delivered in
person, (ii) if sent by express courier service (including, without limitation,
Federal Express, Emery, DHL, Airborne Express, and other similar express
delivery services), (iii) in the event overnight delivery services are not
readily available, if mailed by international airmail, postage prepaid,
registered or certified with return receipt requested, or (iv) if sent by
telecopy and confirmed; provided that, in the case of a notice by telecopy, the
sender shall in addition confirm such notice by writing sent in the manner
specified in clauses (i), (ii) or (iii) of paragraph (a) of this subsection
18.6. All notices shall be effective upon receipt by the addressee; provided,
however, that if any notice is tendered to an addressee and the delivery thereof
is refused by such addressee, such notice shall be effective upon such tender.
For the purposes of notice, the addresses of the parties shall be as set forth
below; provided, however, that any party shall have the right to change its
address for notice hereunder to any other location by giving written notice to
the other party in the manner set forth herein. The initial addresses of the
parties hereto are as follows:

                  If to Owner:

                  Trinidad Ammonia Company, Limited Partnership
                  c/o Trinidad Ammonia Capital, Inc.
                  North Tower
                  World Financial Center
                  250 Vesey Street
                  New York, NY 10281
                  Attention:  Jean M. Tomaselli
                  Telephone:  (212) 449-7925
                  Telecopy:   (212) 449-2854

                  If to Agent:

                  PCS Nitrogen Fertilizer, L.P.
                  3175 Lenox Park Boulevard
                  Suite 400
                  Memphis, Tennessee  38115-4256
                  Attention:  Senior Counsel
                  Telephone:  (901) 758-5375
                  Telecopy:   (901) 758-5201

                           and


                                       53
<PAGE>   55
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  PCS Nitrogen Fertilizer, L.P.
                  3175 Lenox Park Boulevard
                  Suite 400
                  Memphis, Tennessee  38115-4256
                  Attention:  Assistant Treasurer
                  Telephone:  (901) 758-5266
                  Telecopy:   (901) 758-5202

                  With copies to the Guarantor at the following address:

                  Potash Corporation of Saskatchewan Inc.
                  122-1st Avenue South
                  Saskatoon, Saskatchewan S7K 7G3 Canada
                  Attention:  Chief Financial Officer
                  Telecopy:   (306) 933-8844

                           and

                  Potash Corporation of Saskatchewan Inc.
                  122-1st Avenue South
                  Saskatoon, Saskatchewan S7K 7G3 Canada
                  Attention:  General Counsel
                  Telecopy:   (306) 933-8877

With a copy of all notices under this subsection 18.6 to any Assignee at such
address as such Assignee may specify by written notice to Owner and Agent.

                  (b) Owner shall use reasonable efforts to give to Agent,
within five days of receipt, a copy of all notices received by Owner pursuant to
any Credit Agreement and any other notices received with respect to any Unit
Premises, Unit Improvements, item of Unit FF&E, or Unit.

                  18.7 Modifications. Neither this Agreement nor any provision
hereof may be changed, waived or terminated, orally, but only by an instrument
in writing signed by the party against whom enforcement of the change, waiver or
termination is sought.

                  18.8 Rights Cumulative. All rights, powers and remedies herein
given to Owner are cumulative and not alternative, and are in addition to all
statutes or rules of law; any forbearance or delay by Owner in exercising the
same shall not be deemed to be a waiver thereof, and the exercise of any right
or partial exercise thereof shall not preclude the further exercise thereof, and
the same shall continue in full force and effect until specifically waived by an
instrument in writing executed by Owner. All representations and covenants by
Agent shall survive the making of the advances, and


                                       54
<PAGE>   56
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



the provisions hereof shall be binding upon and inure to the benefit of the
respective successors and permitted assigns, if any, of the parties hereto.
Except to the extent provided in subsection 2.1 hereof, Agent may not, however,
assign its rights or obligations as agent hereunder.

                  18.9 GOVERNING LAW. THIS AGREEMENT HAS BEEN EXECUTED AND
DELIVERED IN THE STATE OF NEW YORK. AGENT AND OWNER AGREE THAT, TO THE MAXIMUM
EXTENT PERMITTED BY THE LAWS OF THE STATE OF NEW YORK, THIS AGREEMENT, AND THE
RIGHTS AND DUTIES OF AGENT AND OWNER HEREUNDER, SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK (INCLUDING
WITHOUT LIMITATION SECTIONS 5-1401 AND 5-1402 OF THE NEW YORK GENERAL
OBLIGATIONS LAW) IN ALL RESPECTS, INCLUDING WITHOUT LIMITATION IN RESPECT OF ALL
MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE. AGENT HEREBY IRREVOCABLY
SUBMITS, FOR ITSELF AND ITS PROPERTIES, TO THE JURISDICTION OF THE UNITED STATES
DISTRICT COURT FOR THE SOUTHERN DISTRICT OF NEW YORK AND THE SUPREME COURT OF
THE STATE OF NEW YORK IN THE COUNTY OF NEW YORK IN ANY ACTION, SUIT OR
PROCEEDING BROUGHT AGAINST IT AND RELATED TO OR IN CONNECTION WITH THIS
AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY, AND TO THE EXTENT PERMITTED
BY APPLICABLE LAW, AGENT HEREBY WAIVES AND AGREES NOT TO ASSERT BY WAY OF
MOTION, AS A DEFENSE OR OTHERWISE IN ANY SUCH SUIT, ACTION OR PROCEEDING, ANY
CLAIM THAT IT IS NOT PERSONALLY SUBJECT TO THE JURISDICTION OF SUCH COURT, THAT
THE SUIT, ACTION OR PROCEEDING IS BROUGHT IN AN INCONVENIENT FORUM, THAT THE
VENUE OF THE SUIT, ACTION OR PROCEEDING IS IMPROPER, OR THAT THIS AGREEMENT OR
ANY DOCUMENT OR ANY INSTRUMENT REFERRED TO HEREIN OR THE SUBJECT MATTER HEREOF
MAY NOT BE LITIGATED IN OR BY SUCH COURT. TO THE EXTENT PERMITTED BY APPLICABLE
LAW, AGENT AGREES NOT TO SEEK AND HEREBY WAIVES THE RIGHT TO ANY REVIEW OF THE
JUDGMENT OF ANY SUCH COURT BY ANY COURT OF ANY OTHER NATION OR JURISDICTION
WHICH MAY BE CALLED UPON TO GRANT AN ENFORCEMENT OF SUCH JUDGMENT. AGENT AGREES
THAT SERVICE OF PROCESS MAY BE MADE UPON IT BY CERTIFIED OR REGISTERED MAIL TO
THE ADDRESS FOR NOTICES SET FORTH IN THIS AGREEMENT OR ANY METHOD AUTHORIZED BY
THE LAWS OF NEW YORK. OWNER AND AGENT EXPRESSLY WAIVE ALL RIGHT TO TRIAL BY JURY
IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER IN TORT OR CONTRACT OR
OTHERWISE) RELATED TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.


                                       55
<PAGE>   57
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



OWNER AND AGENT ACKNOWLEDGE THAT THE PROVISIONS OF THIS SUBSECTION 18.9 HAVE
BEEN BARGAINED FOR AND THAT THEY HAVE BEEN REPRESENTED BY COUNSEL IN CONNECTION
THEREWITH.

                  18.10 Confidentiality. Agent and Owner agree to treat
information concerning the structure and documentation of this Agreement and the
Lease confidentially, except to the extent that disclosure is required by law
(in which circumstance such party will use reasonable efforts to notify the
other party prior to such disclosure of any information). The foregoing
constraint shall not include information: (i) that is now in the public domain
or subsequently enters the public domain without fault on the part of the party
proposing to disclose the same; (ii) currently known to Agent or Owner from its
own sources as evidenced by its prior written records; (iii) that Agent or Owner
receives from a third party not under any obligation to keep such information
confidential; and (iv) that is provided by Owner or Agent to counsel,
consultants, other advisors and regulatory authorities, and Assignees or
proposed Assignees, provided that such parties agree (including in writing if so
requested by the non-providing party) to treat any information so provided as
similarly confidential.

                  18.11 Captions. The captions in this Agreement are for
convenience of reference only, and shall not be deemed to affect the meaning or
construction of any of the provisions hereof.

                  18.12 Unit Designation. Owner recognizes Agent's right to call
any Unit by such name or designation as Agent may deem appropriate or reliable
in the ordinary course of Agent's business and to place such signs, labels,
plates or other markings on any Unit Premises, Unit Improvements or Unit as
Agent may desire in exercising such right, subject to the provisions of
subsection 9.11 hereof.

                  18.13 Owner Capitalization. Owner shall provide to Agent on
the date hereof and hereafter upon the reasonable request of Agent, a balance
sheet of Owner certified by Owner and showing that Owner's capitalization is
such that at least four percent (4%) of its capitalization shall consist of
contributions from Owner's general partner and limited partners.

                  18.14 Conveyance of Easements, Etc. In connection with any
sale of any Unit Premises, Unit Improvements, Unit FF&E or Unit pursuant to this
Agreement, Owner shall convey, and the purchaser shall accept a conveyance of,
Owner's interest in the Operating Agreement, the Gas Contract, all easements,
licenses, Ground Leases, Ancillary Facility Agreements and similar agreements
for the benefit of such Unit Premises, Unit Improvements, Unit FF&E or Unit, or
adjacent property, such conveyance to be without warranty by, or recourse to,
Owner, except that such interest shall be free of any Liens resulting from
Owner's willful or knowing act or


                                       56
<PAGE>   58
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



omission unrelated to an occurrence of an Event of Default or an Event of Unit
Termination.

                  SECTION 19.       AGENT'S RIGHT TO PURCHASE

                  Upon the occurrence of an Event of Default and upon the
written request of Agent, which shall be received by Owner and any Assignee not
later than fifteen (15) Business Days subsequent to receipt by Agent of notice
(an "Event of Default Notice") from Owner or any Assignee pursuant to this
Agreement that an Event of Default has occurred, Agent shall have the right, but
not the obligation, not later than thirty (30) Business Days after Agent
receives the notice of the Event of Default from Owner or any Assignee, to
purchase all Units at a price equal to the Unit Acquisition Cost for such Units;
provided that the purchase option contained in this paragraph shall only be
available to Agent if the purchase price and all other amounts paid by Agent
would not in the circumstances in which such payment is made constitute a
preferential payment or a voidable transfer pursuant to the provisions of the
Federal Bankruptcy Code in a bankruptcy proceeding by or against Agent and will
not otherwise result in the payment being subject to recapture from Owner. In
connection with, and as a condition to, the purchase of all Units pursuant
hereto, (i) Agent shall pay at the time of purchase, in addition to the Unit
Acquisition Cost, all other amounts payable by Agent under this Agreement,
including, without limitation, all Accrued Default Obligations, and all transfer
taxes, transfer gains taxes, mortgage recording tax, if any, recording and
filing fees and all other similar taxes, fees, expenses and closing costs
(including reasonable attorneys' fees) in connection with the conveyance of such
Unit to Agent and all other amounts owing hereunder, and (ii) when Owner
transfers title, such transfer shall be on an as-is, non-installment sale basis,
without warranty by, or recourse to, Owner, except that such title shall be free
of any Liens resulting from Owner's willful or knowing act or omission.


                                       57
<PAGE>   59
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  IN WITNESS WHEREOF, the parties have executed this Agreement
the day and year first above written.


                                       Trinidad Ammonia Company, Limited
                                       Partnership, by Trinidad Ammonia Capital,
                                       Inc., its General Partner



                                       By    ___________________________________
                                             Name:
                                             Title:



                                       PCS Nitrogen Fertilizer, L.P.,
                                       by PCS Nitrogen Fertilizer Operations,
                                       Inc.,
                                       its General Partner



                                       By    ___________________________________
                                             Name:
                                             Title:


<PAGE>   60
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                   SCHEDULE I

                      List of Assignment Agreement Consents



1)       Consent with respect to assignment of Water Supply Agreement

2)       Consent with respect to assignment of Electricity Supply Agreement

3)       Consent with respect to assignment of Point Lisas Agreement

4)       Consent with respect to assignment of Savonetta Pier User Agreement

5)       Consent with respect to assignment of Gas Contract
<PAGE>   61
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT A

                  Copy of Amended and Restated Lease Agreement
<PAGE>   62
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT B


AFL UNIT LEASING RECORD to                Lessor:  Trinidad Ammonia Company,
the Amended and Restated Lease                        Limited Partnership
Agreement, dated as of May 16,            Lessee:  PCS Nitrogen Fertilizer, L.P.
1997, between Trinidad Ammonia
Company, Limited Partnership, as
lessor, and PCS Nitrogen Fertilizer, L.P.,
as lessee (the "Lease Agreement").

A.       Unit Premises No.:
         Effective Date of this AFL
         Unit Leasing Record ("AFL ULR") ___________ __, 19__.

B.       PLEASE COMPLETE THE FOLLOWING STATEMENTS, IF
         APPLICABLE:

         1.       This AFL ULR relates to [Deed/Ground Lease] dated ________ __
                  19__.

         UNIT PREMISES DESCRIPTION AND RENTAL INFORMATION.

C.       Type of Property (use category specified in Exhibit A to the Lease
         Agreement)

D.       Specific Description:  (See Schedule A hereto if more space needed)

         _______________________________________________________________________

         _______________________________________________________________________

E.       Location of
         Unit Premises _________________________________________________________
                          State                        County              City
Country

F.       Unit Acquisition Cost under the Amended and Restated Agreement for
         Lease as at the date hereof is $_____________.

G.       If the effective date of this AFL ULR is after the first day of the
         month and prior to the Lease Rate Date in such month, the partial first
         month's Basic Rent for Unit Premises placed under lease by this AFL ULR
         will be paid from the date of this AFL ULR until the end of the month
         on the Basic Rent Payment Date in such month. If the Effective Date of
         the AFL ULR falls on or after the Lease Rate Date, the partial first
         month's Basic Rent will be paid from the date
<PAGE>   63
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



         of this AFL ULR until the end of the month on the next succeeding Basic
         Rent Payment Date.

H.       The Initial Term and Renewal Term for the Unit Premises placed under
         lease pursuant to this AFL ULR will be in accordance with the Lease
         Agreement.

I.       The Basic Rent is as defined in the Lease Agreement.

J.       Termination of the lease of the Property or Equipment leased pursuant
         to this AFL ULR will be in accordance with the Lease Agreement.

K.       ACKNOWLEDGMENT AND EXECUTION

         The undersigned Lessor hereby leases to the undersigned Lessee, and the
         Lessee acknowledges delivery to it in good condition and otherwise as
         required by the Lease of the Unit Premises described on this AFL ULR.
         The Lessee agrees to pay the Basic Rent, Additional Rent and additional
         payments set forth in the Lease Agreement. The covenants, terms and
         conditions of this lease are those appearing in the Lease Agreement, as
         it may from time to time be amended, which covenants, terms and
         conditions are hereby incorporated by reference. The terms used herein
         have the meaning assigned to them in the Lease Agreement.


PCS Nitrogen Fertilizer, L.P.,               Trinidad Ammonia Company,
Lessee                                         Limited Partnership, Lessor
By PCS Nitrogen Fertilizer                   By Trinidad Ammonia Capital, Inc.,
Operations, Inc.,                              its General Partner
  its General Partner


                                             By ________________________________
By ________________________________             Name:
   Name:                                        Title:
   Title:


                                        2
<PAGE>   64
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT C

                         FORM OF ACQUISITION CERTIFICATE
             WITH RESPECT TO UNIT PREMISES LOCATED AT _____________*


                  PCS Nitrogen Fertilizer, L.P. ("Agent"), under a certain
Amended and Restated Agreement for Lease (the "Agreement for Lease"), dated as
of May 16, 1997, entered into between Trinidad Ammonia Company, Limited
Partnership ("Owner") and Agent, hereby certifies to Owner and Assignee as
follows:

                  1.       Legal Description. Attached hereto at Tab 1 is a
                           complete and correct copy of the legal description of
                           the Unit Premises located at _____________. The Unit
                           Premises are being (acquired in fee; leased pursuant
                           to a Ground Lease).

                  2.       Unit Plans. Attached hereto at Tab 2 is a complete
                           and correct copy of the Unit Plans for the Unit
                           Improvement to be constructed on the Unit Premises,
                           and initialed to show Agent's and Owner's approval.

                  3.       Unit Budget. Attached hereto at Tab 3 is a complete
                           and correct copy of the Unit Budget for the Unit,
                           including an itemization of all Unit Acquisition
                           Costs to Owner incurred to date or to be incurred in
                           connection with the acquisition of Owner's interest
                           in the Unit Premises and with the construction and
                           equipping of the Unit.

                  4.       Unit FF&E Specifications. Attached hereto at Tab 4 is
                           a complete and correct copy of the Unit FF&E
                           Specifications initialed to show Agent's approval.
                           [IF NO UNIT FF&E ARE CONTEMPLATED, PLEASE INDICATE
                           THIS.]

                  5.       Title Information. Attached hereto at Tab 5 is a copy
                           of the underlying documents of record affecting fee
                           title to the Unit Premises from the appropriate
                           Governmental Authority or such other evidence of
                           title reasonably required by Owner in paragraph (g)
                           of Section 4 of the Agreement for Lease.

--------
*        All capitalized terms used in this Certificate shall have the meanings
         given to such terms in the Agreement for Lease.
<PAGE>   65
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  6.       Utilities. All easements, licenses, rights of way,
                           rights of access and utility services and facilities
                           (including, without limitation, gas, electrical,
                           water and sewage services and facilities) (a) which
                           are necessary and required during the construction
                           period [HAVE BEEN COMPLETED; OR WILL BE AVAILABLE IN
                           SUCH A MANNER THAT CONSTRUCTION WILL NOT BE IMPEDED
                           BY A LACK THEREOF] and (b) which are necessary for
                           the occupancy of the Unit and the installment of the
                           Unit Improvements thereon and for the completion and
                           operation of the Unit in accordance with the Unit
                           Plans are or will be completed in such a manner and
                           at such a time as will assure the completion and
                           operation of the Unit on or before the Unit
                           Completion Date.

                  7.       Permits. All Permits required for the construction of
                           the Unit Improvements (other than the governmental
                           approval of the Town and Country Planning Authority
                           of the Republic of Trinidad and Tobago, which
                           approval will be obtained in the normal course) have
                           been or will be issued in such a manner that
                           construction will not be impeded by a lack thereof.
                           No work for which a Permit or governmental approval
                           is required will be commenced or continued unless and
                           until such permit or governmental approval required
                           therefor has been issued or obtained, and once issued
                           or obtained will remain in full force and effect.

                  8.       Construction Agreement. Attached hereto at Tab 6 is a
                           complete and correct copy of the most recent draft of
                           the Construction Agreement, substantially in the form
                           to be entered into between Agent and the General
                           Contractor.

                  9.       Request for Advance. Attached hereto at Tab 7 is a
                           duly executed AIA Document G722 or a substantially
                           similar document.

                  10.      Representations of Agent. (i) All costs and expenses
                           which are the subject of the Initial Advance
                           requested have been paid in full or will be paid in
                           full out of the proceeds of the Initial Advance, (ii)
                           there are no Liens on the Unit Premises of which
                           Agent has knowledge that are not Permitted Liens,
                           (iii) all representations and warranties made in the
                           Agreement for Lease, in the Lease, and in connection
                           with the Initial Advance, are and remain true and
                           correct in all material respects on and as of the
                           date of the Initial Advance (except to the extent
                           such representations and warranties expressly relate
                           specifically to an earlier date) and


                                        2
<PAGE>   66
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                           (iv) no Event of Default, Potential Default or, with
                           respect to the Unit for which the Initial Advance is
                           requested, Event of Unit Termination or Casualty
                           Event or Potential Event of Unit Termination, under
                           the Agreement for Lease has occurred and is
                           continuing on the date such Initial Advance is to be
                           made or by reason of giving effect to such Initial
                           Advance.

                  11.      Appraisal. If this advance relates to the Ammonia
                           Project, attached hereto at Tab 8 is an appraisal
                           prepared by Arthur Andersen & Co., which appraisal
                           shall include (i) a "value in use" fair market
                           valuation of the Ammonia Project as at July 1, 1996,
                           which fair market valuation shall equal or exceed
                           $75,000,000, and (ii) a "value in use" fair market
                           valuation of the Ammonia Project of at least
                           $68,800,000 as at July 1, 2000.

Dated:  __________ __, 19__                  PCS Nitrogen Fertilizer, L.P., by
                                                 PCS Nitrogen Fertilizer
                                                 Operations Inc., its General
                                                 Partner



                                             By: _______________________________
                                                 Name:
                                                 Title:




Unit Completion Date:


                                                   3
<PAGE>   67
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT D

                       FORM OF INTERIM ADVANCE CERTIFICATE
               WITH RESPECT TO UNIT PREMISES LOCATED AT _________
               IN CONNECTION WITH A REQUEST FOR AN INTERIM ADVANCE


                  PCS Nitrogen Fertilizer, L.P. ("Agent"), under a certain
Amended and Restated Agreement for Lease (the "Agreement"), dated as of May 16,
1997, entered into with Trinidad Ammonia Company, Limited Partnership ("Owner"),
delivers this Interim Advance Certificate pursuant to Section 5 of the Agreement
with respect to the above noted Unit Premises. All terms used in this
Certificate shall have the meanings given to such terms in the Agreement. Agent
hereby certifies to Owner and Assignee as follows:

                  1.       Continuing Representations of Agent. All
                           representations and warranties made in the Agreement,
                           in the Lease, and in connection with the Interim
                           Advance are and remain true and correct in all
                           material respects on and as of the date of the
                           Interim Advance (except to the extent such
                           representations and warranties expressly relate
                           specifically to an earlier date) and no Event of
                           Default, Potential Default or, with respect to the
                           Unit for which the Interim Advance is requested,
                           Event of Unit Termination or Casualty Event or
                           Potential Event of Unit Termination under this
                           Agreement has occurred and is continuing on the date
                           such Interim Advance is to be made or by reason of
                           giving effect to such Interim Advance.

                  2.       Construction Progress. If reasonably requested in
                           writing by Owner at least three (3) Business Days
                           prior to the making of an Interim Advance, attached
                           hereto at Tab 1 is (a) an inspection report from an
                           independent party and (b) true copies of unpaid
                           invoices, receipted bills and Lien waivers and such
                           other supporting information as may be requested by
                           Owner.

                  3.       No Other Security Interests. All materials and
                           fixtures incorporated in the construction of the Unit
                           Improvements have been purchased so that title
                           thereto shall have vested in Owner immediately upon
                           delivery thereof to the Unit Premises, except for
                           Permitted Liens and if requested by Owner at least
                           three (3) Business Days prior to the making of an
                           Interim Advance, attached hereto at Tab 2 are copies
                           of the contracts, bills of sale, statements,
                           receipted vouchers, or other documents under which
                           title thereto is claimed.
<PAGE>   68
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  4.       Statements of Expenditures. If requested in writing
                           by Owner, attached hereto at Tab 3 is a statement
                           setting forth the names, addresses and amounts due or
                           to become due as well as the amounts previously paid
                           to every contractor or subcontractor furnishing
                           materials, performing labor or entering into the
                           construction of any part of the Unit Improvements.

                  5.       Request for Advance. Attached hereto at Tab 4 is a
                           duly executed AIA Document G722 or a substantially
                           similar document.

                  6.       Evidence of Compliance. If requested, attached hereto
                           at Tab 5 are such documents, reports, certificates,
                           affidavits and other information as reasonably
                           required by Owner and any Assignee to evidence
                           compliance by Agent with all of the provisions of the
                           Agreement.

                  7.       Political Risk Insurance. Attached hereto at Tab 6 is
                           evidence that the political risk insurance required
                           by paragraph (d) of Section 10 of the Lease has been
                           obtained.




Dated:  __________ __, 19__                  PCS Nitrogen Fertilizer, L.P., by
                                                 PCS Nitrogen Fertilizer
                                                 Operations, Inc., its General
                                                 Partner



                                             By: _______________________________
                                                 Name:
                                                 Title:


                                        2
<PAGE>   69
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                   EXHIBIT E

                 FORM OF CERTIFICATE OF SUBSTANTIAL COMPLETION
               WITH RESPECT TO UNIT PREMISES LOCATED AT _________
                IN CONNECTION WITH A REQUEST FOR A FINAL ADVANCE


                  PCS Nitrogen Fertilizer, L.P. ("Agent"), under a certain
Amended and Restated Agreement for Lease (the "Agreement"), dated as of May 16,
1997, entered into with Trinidad Ammonia Company, Limited Partnership ("Owner"),
delivers this Certificate of Substantial Completion pursuant to Section 6 of the
Agreement with respect to the above noted Unit Premises. All terms used in this
Certificate shall have the meanings given to such terms in the Agreement. Agent
hereby certifies to Owner and Assignee as follows:

                  1.       Construction and Equipping of the Unit. The Unit
                           Improvements (including all interior finish work, but
                           exclusive of punch list items) has been completed
                           within the Unit Budget and in all material respects
                           in accordance with the Construction Agreement and the
                           Unit Plans and are accepted by Agent.

                  2.       Permits. All Permits and governmental approvals
                           (other than the governmental approval of the Town and
                           Country Planning Authority of the Republic of
                           Trinidad and Tobago, which approval will be obtained
                           in the normal course) with respect to the Unit have
                           been issued or obtained and are in full force and
                           effect.

                  3.       Liens. The Unit, including interior finish work, has
                           been completed as contemplated in paragraph (b) of
                           Section 6 of the Agreement free of all Liens, except
                           for Permitted Liens (all of which are to be itemized
                           as to the nature, amount, claimant and status) and
                           there are no current Permitted Contests with respect
                           to the Unit (or, if any, the nature, amount, claimant
                           and status thereof).

                  4.       Final Survey. Attached hereto at Tab 3 is a final
                           survey showing the completed Unit Improvements, all
                           easements on the Unit Premises and indicating the
                           location of access to the Unit Premises and all
                           utility and water easements directly affecting the
                           Unit Premises.
<PAGE>   70
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                  5.       Utilities. Connection has been made to all
                           appropriate utility facilities and the Unit
                           Improvements are ready for occupancy and operation.

                  6.       Continuing Representations of Agent. All
                           representations and warranties made in the Agreement,
                           in the Lease, and in connection with this Final
                           Advance are and remain true and correct in all
                           material respects on and as of the date of the Final
                           Advance (except to the extent such representations
                           and warranties expressly relate specifically to an
                           earlier date) and no Event of Default, Potential
                           Default or, with respect to the Unit for which the
                           Final Advance is requested, Event of Unit Termination
                           or Casualty Event or Potential Event of Unit
                           Termination under this Agreement has occurred and is
                           continuing on the date such Final Advance is to be
                           made or by reason of giving effect to such Final
                           Advance.

                  7.       AFL Unit Leasing Record. Attached hereto at Tab 4 is
                           a duly executed AFL Unit Leasing Record.

                  8.       Request for Advance. Attached hereto at Tab 5 is a
                           duly executed AIA Document G722 or a substantially
                           similar document.

Dated:  __________ __, 19__                  PCS Nitrogen Fertilizer, L.P., by
                                                 PCS Nitrogen Fertilizer
                                                 Operations, Inc., its General
                                                 Partner



                                             By: _______________________________
                                                 Name:
                                                 Title:


                                        2
<PAGE>   71
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT F

                      FORM OF CERTIFICATE OF INCREASED COST
               WITH RESPECT TO UNIT PREMISES LOCATED AT _________
              IN CONNECTION WITH A REQUEST FOR A COMPLETION ADVANCE


                  PCS Nitrogen Fertilizer, L.P. ("Agent"), under a certain
Amended and Restated Agreement for Lease (the "Agreement"), dated as of May 16,
1997, entered into with Trinidad Ammonia Company, Limited Partnership ("Owner"),
delivers this Certificate of Increased Cost pursuant to Section 7 of the
Agreement with respect to the above noted Unit Premises. All terms used in this
Certificate shall have the meanings given to such terms in the Agreement. Agent
hereby certifies to Owner and Assignee as follows:

                  1.       Continuing Representations of Agent. All
                           representations and warranties made in the Agreement,
                           in the Lease, and in connection with this Completion
                           Advance are and remain true and correct in all
                           material respects on and as of the date of such
                           Completion Advance (except to the extent such
                           representations and warranties expressly relate
                           specifically to an earlier date) and no Event of
                           Default, Potential Default or, with respect to the
                           Unit for which such Completion Advance is requested,
                           Event of Unit Termination or Casualty Event or
                           Potential Event of Unit Termination under this
                           Agreement has occurred and is continuing on the date
                           such Completion Advance is to be made or by reason of
                           giving effect to such Completion Advance.

                  2.       Revised AFL Unit Leasing Record. Attached hereto at
                           Tab 1 is a revised AFL Unit Leasing Record prepared
                           by Agent.

                  3.       Request for Advance. Attached hereto at Tab 2 is a
                           duly executed AIA Document G722 or a substantially
                           similar document.

                  4.       Representations of Guarantor. All representations and
                           warranties of the Guarantor in the PCS Guaranty are
                           and remain true and correct in all material respects
                           on and as of the date of this Completion Advance as
                           if made on and as of the date of such Completion
                           Advance (except to the extent such representations
                           and warranties expressly relate specifically to an
                           earlier date) and no event of default under the PCS
                           Guaranty has occurred and is


<PAGE>   72
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                           continuing on the date such Completion Advance is to
                           be made or by reason of giving effect to such
                           Completion Advance.


Dated:  __________ __, 19__                  PCS Nitrogen Fertilizer, L.P.,
                                             by PCS Nitrogen Fertilizer
                                             Operations, Inc.,
                                             its General Partner



                                             By: _______________________________
                                                 Name:
                                                 Title:


                                        2
<PAGE>   73
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT G

                            UNIT FF&E SPECIFICATIONS
<PAGE>   74
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT H

                            ENVIRONMENTAL CERTIFICATE


                  1. PCS Nitrogen Fertilizer, L.P. ("Agent"), is a party to a
certain Amended and Restated Agreement for Lease, dated as of May 16, 1997 (the
"Agreement for Lease"), entered into with Trinidad Ammonia Company, Limited
Partnership ("Owner"). Agent is herewith delivering to Owner and Cooperatieve
Centrale Raiffeisen-Boerenleenbank B.A. "Rabobank Nederland", New York Branch
(the "Assignee") an Acquisition Certificate with respect to a leasehold interest
in certain premises located at the Ward of Couva, County of Caroni in the
Republic of Trinidad and Tobago. Capitalized terms used herein and not otherwise
defined shall have the meaning given such terms in the Agreement for Lease.

                  2. Except as described in the Environmental Report
(hereinafter defined), Agent has no actual knowledge and has not given or
received any notice indicating, that (a) any prior or present owner, operator,
tenant or occupant of any portion of the Unit has spilled, released, disposed
of, or discharged (collectively "managed") any Hazardous Substances (hereinafter
defined) on, from, beneath or affecting the Unit or any portion thereof in
amounts or concentrations requiring remediation under applicable Environmental
Regulations; (b) any prior or present owner, operator, tenant or occupant of any
portion of the Unit Premises has received any notice, directive, citation,
subpoena, summons, order to show cause, complaint or other communication from
any Governmental Authority or entity or Person with respect to the management of
any Hazardous Substances on, from, beneath or affecting the Unit Premises or any
portion thereof; (c) Agent has not given notice to any insurance broker or
insurance carrier under any insurance policy that there has been an occurrence
relating to the release of Hazardous Substances on, from, beneath, or affecting
the Unit or any portion thereof; or (d) there are currently any agreements,
consent orders, decrees or other directives of any applicable court or
governmental or quasi-governmental agency requiring any tests, studies,
inspections, work, monitoring or other removal or remedial activities with
respect to the management of any Hazardous Substances on, from, beneath or
affecting the Unit Premises or any portion thereof, or any threatened proceeding
concerning the Unit Premises or any portion thereof which is related to
Environmental Regulations (hereinafter defined).

                  3. For purposes of this document, the following terms shall
have the following meanings: (i) "Environmental Regulations" shall mean each and
every applicable federal, state or local law, statute, ordinance, code, rule,
order, regulation, or other published requirement (including but not limited to,
consent decrees and administrative orders) of any jurisdiction regulating,
relating or imposing obligations, liabilities or standards of conduct with
respect to human health or safety, to the environment, or to Hazardous
Substances, including, without limitation, the
<PAGE>   75
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



Comprehensive Environmental Response, Compensation, and Liability Act, as
amended ("CERCLA") (42 U.S.C. Section 9601, et seq.), as amended by the
Superfund Amendments and Reauthorization Act of 1986 (42 U.S.C. Sections
9601-9675), the Resource Conservation and Recovery Act, as amended (42 U.S.C.
Section 6901, et seq.), the Emergency Planning and Community Right-To-Know Act,
as amended (42 U.S.C. Section 11001, et seq.) the Water Pollution Control Act,
as amended (33 U.S.C. Section 1251, et seq.), the Hazardous Materials
Transportation Act, as amended (49 U.S.C. Section 1801, et seq.), the Toxic
Substances Control Act, as amended (15 U.S.C. Section 2601, et seq.), and any so
called "Superfund" or "Superlien" law, (ii) "Environmental Report" shall mean
the environmental report delivered pursuant to paragraph (v) of Section 4 of the
Agreement for Lease to and accepted by Owner and the Assignee in connection with
the acquisition of the Unit Premises, and (iii) "Hazardous Substances" shall
mean, without limitation, any solid, liquid or gaseous wastes, substances or
materials containing or constituting urea formaldehyde, polychlorinated
biphenyls, petroleum products, methane, radioactive materials, hazardous wastes,
hazardous or toxic substances, or related materials, asbestos or any material
containing asbestos, pollutants, or any other substance, material, chemical
compound, waste or item defined as or determined by a governmental authority
having jurisdiction to be hazardous or toxic pursuant to any Environmental
Regulations applicable to the Unit Premises or the business operations conducted
thereon.



                                   PCS Nitrogen Fertilizer, L.P., by
                                      PCS Nitrogen Fertilizer Operations, Inc.,
                                      its General Partner


                                            By: ________________________________

                                            Title: _____________________________



                                        2
<PAGE>   76
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT I

                               OPERATING AGREEMENT
<PAGE>   77
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT J

                       DESCRIPTION OF THE AMMONIA PROJECT
<PAGE>   78
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT K

                                 PROJECT PARCEL
<PAGE>   79
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT L

                   CONSTRUCTION AGREEMENT FOR AMMONIA PROJECT
<PAGE>   80
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                   EXHIBIT M-1

                          ELECTRICITY SUPPLY AGREEMENT
<PAGE>   81
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                   EXHIBIT M-2

                             WATER SUPPLY AGREEMENT
<PAGE>   82
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                   EXHIBIT M-3

                          SAVONETTA PIER USER AGREEMENT
<PAGE>   83
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT N

                            FORM OF AIA DOCUMENT G722
<PAGE>   84
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



                                    EXHIBIT O

                               REVISED UNIT BUDGET
<PAGE>   85
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY

<TABLE>
<CAPTION>
                                             TABLE OF CONTENTS
                                                                                                      Page

<S>                <C>                                                                                <C>
SECTION 1.         DEFINITIONS.........................................................................  1

SECTION 2.         APPOINTMENT OF AGENT................................................................ 11

SECTION 3.         ADVANCES............................................................................ 14

SECTION 4.         CONDITIONS PRECEDENT TO THE INITIAL ADVANCE
                   WITH RESPECT TO A UNIT.............................................................. 15

SECTION 5.         CONDITIONS PRECEDENT TO OWNER'S OBLIGATION
                   TO MAKE INTERIM ADVANCES AFTER THE INITIAL
                   ADVANCE WITH RESPECT TO A UNIT...................................................... 19

SECTION 6.         CONDITIONS PRECEDENT TO THE FINAL ADVANCE
                   WITH RESPECT TO A UNIT.............................................................. 21

SECTION 7.         CONDITIONS PRECEDENT TO COMPLETION
                   ADVANCES WITH RESPECT TO A UNIT..................................................... 22

SECTION 8.         REPRESENTATIONS AND WARRANTIES OF AGENT............................................. 23

SECTION 9.         AFFIRMATIVE COVENANTS............................................................... 28

SECTION 10.        NEGATIVE COVENANTS.................................................................. 34

SECTION 11.        EVENTS OF DEFAULT, EVENTS OF UNIT
                   TERMINATION AND CASUALTY EVENTS..................................................... 35

SECTION 12.        INDEMNITIES......................................................................... 44

SECTION 13.        LEASEHOLD INTERESTS................................................................. 45

SECTION 14.        PURCHASES........................................................................... 45

SECTION 15.        CHARACTER OF AMMONIA PROJECT........................................................ 45

SECTION 16.        PERMITTED CONTESTS.................................................................. 45

SECTION 17.        SALE OR ASSIGNMENT BY OWNER......................................................... 47

SECTION 18.        GENERAL CONDITIONS.................................................................. 47
</TABLE>

                                        i
<PAGE>   86
                                   THIS AMENDED AND RESTATED AGREEMENT FOR LEASE
                                                 IS CONFIDENTIAL AND PROPRIETARY



SECTION 19.        AGENT'S RIGHT TO PURCHASE................................. 55



Schedule I                 List of Assignment Agreement Consents

<TABLE>
<CAPTION>
                                          EXHIBITS
                                          --------

<S>                        <C>
Exhibit A                  The Amended and Restated Lease Agreement
Exhibit B                  Form of AFL Unit Leasing Record
Exhibit C                  Form of Acquisition Certificate
Exhibit D                  Form of Interim Advance Certificate
Exhibit E                  Form of Certificate of Substantial Completion
Exhibit F                  Form of Certificate of Increased Cost
Exhibit G                  Unit FF&E Specifications
Exhibit H                  Environmental Certificate
Exhibit I                  Operating Agreement
Exhibit J                  Description of the Ammonia Project
Exhibit K                  Project Parcel
Exhibit L                  Construction Agreement for Ammonia Project
Exhibit M-1                Electricity Supply Agreement
Exhibit M-2                Water Supply Agreement
Exhibit M-3                Savonetta Pier User Agreement
Exhibit N                  Form of AIA Document G722
Exhibit O                  Revised Unit Budget
</TABLE>

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