- 1 -

                                                                  EXECUTION COPY

                                             ASSIGNMENT AND ACCEPTANCE


         Reference is made to the Credit and  Guarantee  Agreement,  dated as of
October 15,  1993,  as amended and  restated as of February 27, 1997 (as further
amended,  supplemented  or  otherwise  modified  from time to time,  the "Credit
Agreement"), among North American Chemical Company, North American Salt Company,
Great Salt Lake Minerals  Corporation  (collectively,  the "Borrowers"),  Harris
Chemical North America,  Inc.  ("HCNA"),  as guarantor  (together with the other
"Guarantors",  as defined under the Credit  Agreement,  the  "Guarantors"),  the
banks and other  financial  institutions  parties  thereto (the  "Lenders")  and
General Electric Capital Corporation, as collateral agent (in such capacity, the
"Collateral   Agent")  and   administrative   agent  (in  such   capacity,   the
"Administrative Agent") for the Lenders.

Unless otherwise defined herein,  terms defined in the Credit Agreement and used
herein shall have the meanings given to them in the Credit Agreement.

         Each assignor  listed on SCHEDULE 1 hereto (each,  an "Assignor",  and,
collectively,  the  "Assignors"),  the assignee listed on SCHEDULE 1 hereto (the
"Assignee"),  each Borrower,  each Guarantor,  the Administrative  Agent and the
Collateral Agent agree as follows:

         1. The Assignors  hereby  severally  irrevocably sell and assign to the
Assignee without recourse to any Assignor,  and the Assignee hereby  irrevocably
purchases and assumes from the Assignors without recourse to any Assignor, as of
the Effective Date (as defined below),  interests (each, an "Assigned Interest")
in and to the Assignors'  rights and obligations  under the Credit Agreement and
each other Loan  Document with respect to those credit  facilities  contained in
the Credit  Agreement  as are set forth on SCHEDULE 1 hereto  (individually,  an
"Assigned Facility"; collectively, the "Assigned Facilities"), in the respective
amounts  such that the  principal  amount  of each  Assigned  Facility  sold and
assigned  by each  Assignor  shall be the amount set forth on  SCHEDULE 1 hereto
under the caption  "ASSIGNORS"  opposite such  Assignor's name and the principal
amount of each Assigned Facility  purchased and assumed by the Assignee shall be
the amount set forth on SCHEDULE 1 hereto under the caption "ASSIGNEE"  opposite
the Assignee's name. The successor Administrative Agent (as defined in Section 3
below) agrees to pay to the Administrative Agent for value on the Effective Date
(for   distribution  to  the  Assignors)  the  aggregate  amount  of  the  Loans
outstanding under the Credit Agreement, as set forth on SCHEDULE 1 hereto.

         2. Each Assignor (a) makes no representation or warranty and assumes no
responsibility  with respect to any  statements,  warranties or  representations
made in or in connection  with the Credit  Agreement or the other Loan Documents
or the execution, legality, validity, enforceability,  genuineness, sufficiency,
value or  perfection  of the Credit  Agreement,  any other Loan  Document or any
other instrument or document furnished pursuant thereto,  other than that it has
not created any adverse claim upon the Assigned  Interest  being  assigned by it
hereunder and that such Assigned  Interest is free and clear of any such adverse
claim; and (b) makes no representation or warranty and assumes no responsibility
with respect to the financial condition

K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 2 -

                                                                  EXECUTION COPY

of any Borrower,  any Guarantor,  any Subsidiary of any Borrower or Guarantor or
any  other  obligor  or the  performance  or  observance  by any  Borrower,  any
Guarantor,  any  Subsidiary of any Borrower or Guarantor or any other obligor of
any of their respective obligations under the Credit Agreement or the other Loan
Documents  or any other  instrument  or document  furnished  pursuant  hereto or
thereto.

         3.  Each   Administrative   Agent  and  Collateral   Agent  resigns  as
Administrative  Agent  and  Collateral  Agent,  respectively,  effective  on the
Effective Date. Each Borrower,  Guarantor and Lender agrees to such resignations
and waives the  requirement  under  Section  13.9 of the Credit  Agreement  that
notice  of such  resignation  be given 10 days  prior to such  resignation.  The
Assignee  under the  Credit  Agreement  has  appointed  and the  Borrowers  have
approved the  appointment of IMC Global Inc. as successor  Administrative  Agent
and successor  Collateral Agent,  which  appointments  shall be effective on the
Effective  Date,  whereupon such successor  administrative  agent and collateral
agent  shall  succeed to the rights and duties of the  Administrative  Agent and
Collateral  Agent,  and the term  "Administrative  Agent" or "Collateral  Agent"
under the Loan  Documents  shall  mean such  successor  administrative  agent or
collateral agent, and the rights, powers and duties of the former Administrative
Agent or Collateral  Agent (in its capacity as such),  as the case may be, shall
be  terminated,  without  any other or  further  act or deed on the part of such
former  Administrative  Agent or Collateral  Agent or any of the parties to this
Assignment and Acceptance or the Credit Agreement.

         4.  The  Assignee  (a)  represents  and  warrants  that  it is  legally
authorized to enter into this  Assignment and  Acceptance;  (b) confirms that it
has  received  a copy of the  Credit  Agreement,  together  with  copies  of the
financial  statements  delivered  pursuant to Section 7.1 thereof and such other
documents and  information  as it has deemed  appropriate to make its own credit
analysis and decision to enter into this Assignment and  Acceptance;  (c) agrees
that it  will,  independently  and  without  reliance  upon  any  Assignor,  the
Administrative Agent, the Collateral Agent or any other Lender and based on such
documents and information as it shall deem appropriate at the time,  continue to
make its own credit  decisions  in taking or not taking  action under the Credit
Agreement, each other relevant Loan Document or any other instrument or document
furnished pursuant hereto or thereto;  (d) appoints and authorizes the successor
Administrative Agent with respect to the Credit Agreement to take such action as
agent on its behalf and to exercise such powers and discretion  under the Credit
Agreement, the other relevant Loan Documents or any other instrument or document
furnished  pursuant  hereto  or  thereto  as are  delegated  to  such  successor
Administrative  Agent by the terms  thereof,  together  with such  powers as are
incidental  thereto;  and (e) agrees that it will be bound by the  provisions of
the Credit  Agreement and each other  relevant Loan Document and will perform in
accordance with its terms all the  obligations  which by the terms of the Credit
Agreement  or such other Loan  Document  are required to be performed by it as a
Lender. The successor  Administrative  Agent, the successor Collateral Agent and
the Assignee confirm that none of the Assignors, the Administrative Agent or the
Collateral Agent shall have any obligation whatsoever at any time to provide any
of them  with  any  information  or  document  in  connection  with  the  Credit
Agreement.


K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 3 -

                                                                  EXECUTION COPY

         5. This  Assignment and Acceptance  shall become  effective on April 1,
1998 (the  "Effective  Date"),  provided that (A) the  Administrative  Agent has
received  for value on that day the  amounts  payable  under  Sections  1, 6 and
10(c)(ii)  and (iii)  hereof,  and all other  amounts  that may  become  payable
hereunder on such day, and (B) the other conditions precedent to this Assignment
and Acceptance becoming effective set forth in Section 8 hereof are satisfied on
or before such date. The conditions  precedent to this Assignment and Acceptance
becoming  effective  contained  in  clauses  (A) and (B) of this  Section  5 are
inserted  solely for the benefit of the  Administrative  Agent,  the  Collateral
Agent  and  the  Lenders.   Following  the  execution  of  this  Assignment  and
Acceptance,  it will be delivered to the Administrative  Agent for acceptance by
it and  recording by the  Administrative  Agent  pursuant to Section 14.7 of the
Credit Agreement, effective as of the Effective Date.

         6. From and after the  Effective  Date,  the  successor  Administrative
Agent shall make all  payments in respect of the Assigned  Interests  (including
payments of principal, interest, fees and other amounts) to the Assignee. On the
Effective  Date,  each  Borrower  shall  pay to  the  Administrative  Agent  for
distribution to each Assignor, the Administrative Agent and the Collateral Agent
all accrued  interest,  fees and other  accounts  owing by such Borrower to such
Assignor,  Administrative Agent and Collateral Agent under the Credit Agreement,
as set forth in SCHEDULE 2 hereto.

         7. From and after the Effective Date, (a) the Assignee shall be a party
to the Credit  Agreement  and,  to the extent  provided in this  Assignment  and
Acceptance, have the rights and obligations of a Lender thereunder and under the
other relevant Loan  Documents and shall be bound by the provisions  thereof and
(b)  each  Assignor  shall,  to the  extent  provided  in  this  Assignment  and
Acceptance, relinquish its rights and be released from its obligations under the
Credit Agreement and other Loan Documents.

         8. With respect to the Credit Agreement, each Borrower and the Assignee
hereby agree, as a condition  precedent to the  effectiveness of this Assignment
and  Acceptance,  that,  as to each  letter of credit  identified  in SCHEDULE 3
hereto, it shall deliver to the  Administrative  Agent (A) a letter of credit in
form and substance and amount,  and issued by a party or (B) cash  collateral in
an amount,  in each case,  acceptable  to the  Administrative  Agent in its sole
discretion.

         9. At any time and from time to time, each of the Administrative Agent,
the  Collateral  Agent and the Lenders  agrees that it will  cooperate  with the
successor  Administrative  Agent  and the  successor  Collateral  Agent and will
execute and  deliver,  or cause to be executed and  delivered,  all such further
instruments and documents,  and will take all such further  actions,  including,
without limitation, the execution and delivery to the successor Collateral Agent
for filing by the successor  Collateral Agent of UCC-3  assignments of financing
statements,  discharges,  lockbox  agreement  terminations and other release and
termination  documents,  in each case,  as the  successor  Collateral  Agent may
reasonably  request  following the delivery of such  instruments,  documents and
other items to the Administrative Agent, the Collateral Agent

K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 4 -

                                                                  EXECUTION COPY

and/or the Lenders,  as  applicable,  in order to carry out the  provisions  and
purposes of this Agreement.  Each of the  Administrative  Agent,  the Collateral
Agent and the Lenders further agrees to promptly  deliver to HCNA all promissory
notes, and to the successor  Collateral  Agent all stock  certificates and other
instruments,  in its possession with respect to the  Obligations.  The Borrowers
agree to reimburse each of the  Administrative  Agent,  the Collateral Agent and
the Lenders on demand for its reasonable costs and expenses (including,  without
limitation,  reasonable  legal  fees)  incurred  by it in  connection  with  the
performance of any actions that it is requested to perform hereunder.

         10. With respect to the Credit Agreement, each of the Borrowers and the
Guarantors hereby jointly and severally agrees to the terms set forth in Section
8 hereof, and each hereby:

         (a)      releases the  Administrative  Agent,  the Collateral Agent and
                  the Lenders  with  respect to the Credit  Agreement  and other
                  Loan Documents from any and all obligations  owing under or in
                  connection  with  the  Credit  Agreement  and the  other  Loan
                  Documents,  including,  without limitation,  any obligation to
                  make Revolving Credit Loans or to incur L/C Obligations  under
                  the Credit Agreement;

         (b)      releases the  Administrative  Agent,  the Collateral Agent and
                  the  Lenders  from any and all claims,  liabilities,  damages,
                  costs and expenses now existing or hereafter arising out of or
                  in  connection  with the Credit  Agreement  and the other Loan
                  Documents;

         (c)      agrees that it shall pay (i) on demand,  from time to time, to
                  the  Collateral Agent the full  amount of customer  checks and
                  other remittances  which have been applied  to the Obligations
                  (or credited for  the purposes of determining  the amounts set
                  forth on SCHEDULE 2  hereto)  and which are returned unpaid or
                  reversed  for  any  reason  and (ii)  on the date  hereof, all
                  reasonable costs and expenses, including,  without limitation,
                  reasonable legal fees,  in connection with the  preparation of
                  draft  payoff   and  release  letters  and  the   preparation,
                  execution and delivery of this  Assignment and  Acceptance and
                  the  performance  of  any other  acts  required to  effect the
                  release of any security interest, hypothec, assignment, charge
                  or pledge granted under the Loan Documents,  (iii) on the date
                  hereof,  any and all taxes and fees payable in connection with
                  the  execution  and  delivery,  filing  or  recording of  this
                  Assignment and Acceptance and other  instruments and documents
                  to  be  delivered  hereunder,   and  further  agrees  to  save
                  Administrative Agent,  the Collateral  Agent and  the  Lenders
                  harmless from and against any and all liabilities with respect
                  to or  resulting  from  any  reasonable  delay  in  paying  or
                  omitting  to pay such taxes or fees and  (iv) on demand,  from
                  time to time,  to the  Collateral Agent,  normal and customary
                  fees, charges and expenses incurred by the Collateral Agent in
                  respect  of the  letters of credit  identified  in  SCHEDULE 3
                  hereto; and


K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 5 -

                                                                  EXECUTION COPY

         (d)      agrees  that it shall  be liable  with respect to,  and  shall
                  indemnify and hold the  Administrative Agent,  the  Collateral
                  Agent and the Lenders harmless from, the amount of any payment
                  by  it  to the  relevant  Administrative  Agent,  the relevant
                  Collateral Agent and the relevant Lenders which any of them is
                  for any reason compelled to surrender  to any  person  because
                  such  payment  is  determined  to  be  void  or  voidable as a
                  preference,  an  impermissible  setoff,  a diversion  of trust
                  funds or for any other reason, until the Administrative Agent,
                  the Collateral Agent and such  Lenders shall have been finally
                  and irrevocably paid all Obligations in full in cash.

         11. All payments by the successor  Administrative  Agent, each Borrower
and each Guarantor to the  Administrative  Agent pursuant to this Assignment and
Acceptance shall be made by wire transfer as follows:

                  Bank:                     Bankers Trust Company, New York,
                                            New York

                  ABA No.:                  021001033

                  Account No.:              50-232-854

                  Account Name:             General Electric Capital Corporation

                  Reference:                CFC - Harris Chemical

         12. Each party  hereto  agrees  that the  assignments  of the  Assigned
Interests hereunder shall be effective notwithstanding that such assignments may
not comply in all respects with the provisions of the Credit Agreement.

         13. This  Assignment and Acceptance  shall be governed by and construed
in  accordance  with the laws of the  State of New York  (without  regard to the
conflict of laws provisions thereof other than ss.5-1401 of the New York General
Obligations Law).

         14. This  Assignment  and  Acceptance may be executed by one or more of
the  parties  to this  Assignment  and  Acceptance  in any  number  of  separate
counterparts  (including  by  telecopy),  and  all of  such  counterparts  taken
together shall be deemed to constitute one and the same instrument.


K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 6 -

                                                                  EXECUTION COPY

         IN WITNESS WHEREOF,  the parties hereto have caused this Assignment and
Acceptance  to be  executed  as of  April  1,  1998  by  their  respective  duly
authorized officers.

                                                     The Assignors:

GENERAL ELECTRIC CAPITAL
CORPORATION, as Lender

By: _/s/ Rick Luck________________
Name:
       Being Duly Authorized


BANKBOSTON, N.A., as Lender

By: _/s/ Mark J. Forti____________
Name:  Mark J. Forti
Title:  Vice President


HELLER FINANCIAL INC., as Lender

By: _/s/ Thomas W. Bukowski_______
Name:  Thomas W. Bukowski
Title:  Sr. Vice President


BANKAMERICA BUSINESS CREDIT, INC., as
Lender

By: _/s/ Beverly J. Gray__________
Name:  Beverly J. Gray
Title:  Sr. Account Executive

THE CIT GROUP/BUSINESS CREDIT INC.,
as Lender

By: _/s/ Nicole Cangelosi_________
Name:  Nicole Cangelosi
Title:  Assistant Secretary


K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 7 -

                                                                  EXECUTION COPY

The Assignee:

IMC GLOBAL INC.

By: _/s/ Eric T. Martinez_________
Name:  Eric T. Martinez
Title:  Assistant Treasurer

By: _/s/ Rose Marie Williams______
Name:  Rose Marie Williams
Title:  Corporate Secretary

Borrowers and Guarantors:

NORTH AMERICAN SALT COMPANY,
as Borrower

By: _/s/ Richard J. Nick__________
Name:  Richard J. Nick
Title:  Sr. Vice President


NORTH AMERICAN CHEMICAL
COMPANY, as Borrower

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President


GREAT SALT LAKE MINERALS
CORPORATION, as Borrower

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President



K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 8 -

                                                                  EXECUTION COPY

HARRIS CHEMICAL NORTH
AMERICA INC., as Guarantor

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President


NAMSCO, INC., as Guarantor

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President


CAREY SALT COMPANY, as Guarantor

By: _/s/ Richard J. Nick__________
Name:  Richard J. Nick
Title:  Vice President


GSL CORPORATION, as Guarantor

By: _/s/ Richard J. Nick__________
Name:  Richard J. Nick
Title:  Vice President


GSL HOLDINGS INC., as Guarantor

By:  ___n/a_______________________
Name:
Title:


THE HUTCHINSON & NORTHERN
RAILWAY COMPANY, as Guarantor

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President


K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 9 -

                                                                  EXECUTION COPY

NORTH AMERICAN TERMINALS,
INC., as Guarantor

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President


OLDEXAER, INC., as Guarantor

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President


WRNM HOLDINGS, INC., as Guarantor

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Vice President


WHITE RIVER NAHCOLITE MINERALS
LIMITED LIABILITY COMPANY,
as Guarantor

By:  _/s/ Richard J. Nick_________
Name:  Richard J. Nick
Title:  Manager

Accepted:

GENERAL ELECTRIC CAPITAL
CORPORATION, as Administrative Agent and
Collateral Agent


By: _/s/ Rick Luck________________
Name:
      Being Duly Authorized




K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                     - 10 -

                                                                  EXECUTION COPY

Accepted:

IMC GLOBAL INC., as successor Administrative
Agent and successor Collateral Agent


By: _/s/ Eric T. Martinez_________
Name:  Eric T. Martinez
Title:  Assistant Treasurer

By:_/s/ Rose Marie Williams_______
Name:  Rose Marie Williams
Title:  Corporate Secretary



K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE

<PAGE>


                                                                  EXECUTION COPY

                                   SCHEDULE 1
                          TO ASSIGNMENT AND ACCEPTANCE
                                   Relating to
 the Credit and  Guarantee  Agreement,  dated as of October 15, 1993, as amended
and  restated as of  February  27, 1997 (as  further  amended,  supplemented  or
otherwise  modified  from time to time,  the  "Credit  Agreement"),  among North
American Chemical Company, North American Salt Company, Great Salt Lake Minerals
Corporation  (collectively,  the  "Borrowers"),  Harris  Chemical North America,
Inc., as guarantor (together with the other  "Guarantors",  as defined under the
Credit Agreement, the "Guarantors"),  the banks and other financial institutions
parties thereto (the "Lenders") and General  Electric  Capital  Corporation,  as
collateral agent (in such capacity,  the "Collateral  Agent") and administrative
agent (in such capacity, the "Administrative Agent") for the Lenders


<TABLE>
<CAPTION>

-------------------------------------------------------------------------------------------------------------------



ASSIGNORS:

<S>                                                   <C>                       <C>                <C>

Name of                                                Commitment --            Commitment             Loans --
Assignor                                              Credit Agreement          Percentage         Credit Agreement
--------                                              ----------------          ----------         ----------------
General Electric Capital Corporation                       $42,666,667          32.82051%            $20,546,237.59
Heller Financial Inc.                                      $35,000,000          26.92308%            $16,854,338.90
BankBoston, N.A.                                           $20,000,000          15.38462%             $9,631,052.59
BankAmerica Business Credit, Inc.                          $17,333,333          13.33333%             $8,346,907.65
The CIT Group/Business Credit Inc.                         $15,000,000          11.53846%             $7,223,286.31





ASSIGNEE:


Name of                                                 Commitment --           Commitment             Loans --
Assignee                                              Credit Agreement          Percentage         Credit Agreement
IMC Global Inc.                                           $130,000,000             100%              $62,601,823.04


</TABLE>



K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE
                                    Sch 1 - 1

<PAGE>


                                                                  EXECUTION COPY

                                   SCHEDULE 2
                          TO ASSIGNMENT AND ACCEPTANCE
                                   Relating to
 the Credit and  Guarantee  Agreement,  dated as of October 15, 1993, as amended
and  restated as of  February  27, 1997 (as  further  amended,  supplemented  or
otherwise  modified  from time to time,  the  "Credit  Agreement"),  among North
American Chemical Company, North American Salt Company, Great Salt Lake Minerals
Corporation  (collectively,  the  "Borrowers"),  Harris  Chemical North America,
Inc., as guarantor (together with the other  "Guarantors",  as defined under the
Credit Agreement, the "Guarantors"),  the banks and other financial institutions
parties thereto (the "Lenders") and General  Electric  Capital  Corporation,  as
collateral agent (in such capacity,  the "Collateral  Agent") and administrative
agent (in such capacity, the "Administrative Agent") for the Lenders


<TABLE>
<CAPTION>

                                           INTEREST, FEES AND OTHER AMOUNTS
<S>                                                                                                          <C>
Accrued and unpaid interest on Eurodollar Loans as of the Effective Date:                                          $0
Accrued and unpaid interest on Base Rate Loans (including all Swing Line                                     $144,137.48
Loans) as of the Effective Date:
Accrued and unpaid Letter of Credit Commissions as of the Effective Date:                                    $161,563.44
Accrued and unpaid Commitment Fees as of the Effective Date:                                                  $73,976.55
Unpaid reimbursable expenses of the Administrative Agent and the Collateral
Agent as of the Effective Date:                                                                               $21,000.00
                                                                                                             ------------
Total:                                                                                                       $400,677.47
                                                                                                             ============

</TABLE>


K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE
                                    Sch 2 - 1

<PAGE>


                                                                  EXECUTION COPY
                                   SCHEDULE 3
                          TO ASSIGNMENT AND ACCEPTANCE
                                   Relating to
 the Credit and  Guarantee  Agreement,  dated as of October 15, 1993, as amended
and  restated as of  February  27, 1997 (as  further  amended,  supplemented  or
otherwise  modified  from time to time,  the  "Credit  Agreement"),  among North
American Chemical Company, North American Salt Company, Great Salt Lake Minerals
Corporation  (collectively,  the  "Borrowers"),  Harris  Chemical North America,
Inc., as guarantor (together with the other  "Guarantors",  as defined under the
Credit Agreement, the "Guarantors"),  the banks and other financial institutions
parties thereto (the "Lenders") and General  Electric  Capital  Corporation,  as
collateral agent (in such capacity,  the "Collateral  Agent") and administrative
agent (in such capacity, the "Administrative Agent") for the Lenders

<TABLE>
<CAPTION>
                                                 LETTERS OF CREDIT


      <S>                  <C>                                                       <C>             <C>                <C>    
         L/C No.                              Beneficiary                            Amount          Expiry Date        Issuing Bank
         50079492          COUNTY OF SAN BERNARDINO OR THE                               $904,405.00        3/24/99       BankBoston
                           CALIFORNIA DEPARTMENT OF
                           CONSERVATION
         50079505          AMERICAN INTERNATIONAL GROUP                                $2,118,000.00        3/24/99       BankBoston
         50079491          FIREMAN'S FUND INSURANCE                                       $20,000.00        3/25/99       BankBoston
                           COMPANY
         50079488          LOUISIANA DEPT OF EMPLOYMENT                                  $450,000.00        3/24/99       BankBoston
                           AND TRAINING OFFICE OF WORKERS
                           COMPENSATION
         50079487          ACSTAR INSURANCE COMPANY                                      $119,600.00        3/27/99       BankBoston
         50079485          ACSTAR INSURANCE COMPANY                                     $4,155,00.00        3/27/99       BankBoston
         50079484          UTAH DIVISION OF OIL, GAS AND                                 $298,900.00         4/8/99       BankBoston
                           MINING
         50079486          RELIANCE NATIONAL INDEMNITY CO.                             $2,275,215.00         5/1/99       BankBoston
         50079490          SAN DIEGO UNIFIED PORT AUTHORITY                              $300,000.00        4/30/99       BankBoston
         50079497          KREDIETBANK NV                                                $110,000.00        4/30/99       BankBoston
         S970253           GENERAL ELECTRIC CAPITAL                                    $5,860,441.00        7/14/98        ABN AMRO
                           CORPORATION
         S970254           GENERAL FOODS CREDIT INVESTORS                              $7,511,927.00        7/14/98        ABN AMRO
         SA99548096        STATE OF COLORADO MINED LAND                                  $150,750.00        3/31/99      NationsBank
                           RECLAMATION BOARD
         SA99516096        COLORADO NATIONAL BANK                                      $1,083,332.81        8/31/98      NationsBank
         SA99517096        WHITE RIVER ELECTRIC ASSOCIATION,                             $492,579.15        3/31/99      NationsBank
      (also identified as     INC.
       099517AVA99517)
                                                                                     ----------------
                                                                       TOTAL:         $25,850,149.96
                                                                                     ================

</TABLE>

K:\BANK\RDJR\GE\SIFTO\ASSIGN-X.AGR                     ASSIGNMENT AND ACCEPTANCE
                                    Sch 3 - 1

<PAGE>