SETTLEMENT AGREEMENT
                              --------------------
                                        
     THIS SETTLEMENT AGREEMENT is made as of the 9th day of March, 1994, between
Mountain Coal  Company and  Atlantic Richfield Company ("Plaintiffs") and Nevada
Power Company ("Defendant").


                                    RECITALS
                                    --------
                                        
     1.        The parties  are engaged  in litigation  before the United States
               District Court  for the  District of  Utah (Civil No. 92-C-522-S)
               concerning three  coal supply  agreements (the  "1980  Agreement,
               "the  "1982   Agreement,"  and  the  "1985  Agreement")  and  one
               agreement for  loading services  ("Loading Agreement") (the "Utah
               Action");
               
     2.        The parties  have agreed  to compromise  and settle their pending
               disputes upon the terms set out below.
               
     NOW, THEREFORE, Plaintiffs and Defendant agree in compromise and settlement
of their claims as follows:

     1.        Defendant shall  pay Plaintiff ARCO $25,000,000 for coal not sold
               under the  1985 Agreement  from December  31, 1992,  through  the
               expiration of  the term  of the  1985 Agreement,  and for loading
               services not  performed under the Loading Agreement, according to
               the terms of a promissory note annexed hereto as Exhibit A, which
               note shall  be executed  by Defendant concurrently with execution
               by Defendant of this Settlement Agreement.
               
     2.        Defendant shall  pay Plaintiff  ARCO $310,552  in satisfaction of
               certain price  adjustments for  past deliveries  under  the  1985
               Agreement, made  over the period 1987-1991, which sum is included
               in the annexed Promissory Note.
               
     3.        The  parties   shall  cause   their  legal   counsel  to  do  the
               following(except as  may be  required  to  preserve  the  pricing
               approach approved  by  the  court  in  Civil  No.  92-C-522-S  as
               contained in      paragraph 9 of its July 30, 1993, Order) within
               ten (10) days of the date of this Agreement:
               
               a.   Defendant shall  dismiss with  prejudice its  appeal pending
                    before the  United States  Court of  Appeals for  the  Tenth
                    Circuit, Case No. 93-4165;
                    
               b.   Defendant shall  dismiss with  prejudice all  claims pending
                    against Plaintiffs in the Utah Action;
                    
               c.   Plaintiffs shall  dismiss with  prejudice all claims pending
                    by Plaintiffs against Defendant in the Utah Action;
                    
               d.   All parties shall dismiss the Utah action.
               
     4.        The parties  specifically exclude  from this Settlement Agreement
               the  retroactive   adjustment  amounts   on  the  1980  and  1982
               Agreements as detailed in ARCO's letter of January 6, 1994, which
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               amounts are  subject to  ongoing audit  and possible  adjustment.
               The parties  further  understand  that  performance  under  these
               Agreements is  ongoing and  that NPC has not completed its audits
               for deliveries under these agreements for the years 1991 to date.
               These audits will be completed in the ordinary course, using West
               Elk actual costs as approved by the Court in Civil No. 92-C-522-S
               in paragraph 9 of its July 30, 1993, Order.

     5.        The parties  acknowledge and  agree that  the 1985  Agreement and
               Loading Agreement  are at  an end  as of  midnight, December  31,
               1992.   The parties  confirm and  agree that  the 1980  and  1982
               Agreements are  in full  force and  effect and  that, apart  from
               price adjustments,  including without  limitation any  applicable
               retroactive adjustments  as may  be required  thereunder: (1)  no
               party has  any claim  against the  other under either the 1980 or
               1982 Agreements,  (2) no party is in default thereunder as of the
               date hereof,  and (3) except for possible retroactive adjustments
               as described in paragraph 4 above, each party hereby releases any
               and all claims, known or unknown, which each may have against the
               other party  based upon any action or inaction occurring prior to
               the date  of this  Agreement arising  out of or in consequence of
               any of  the three  Coal Supply agreements or the Loading Services
               Agreement.
               
     6.        Each party shall bear its own costs and attorneys' fees for or in
               connection with this litigation.

     7.        This Settlement  Agreement contains  the entire agreement between
               the parties  respecting settlement  of the  disputes between them
               and there  exists no  other covenant, representation or agreement
               respecting the subject matter hereof between the parties.
               
NEVADA POWER COMPANY                         MOUNTAIN COAL COMPANY

By:  David G. Barneby                        By:  Anthony G. Fernandes
     An Authorized Representative                 An Authorized Representative

Title:    Vice President - Power Delivery    Title:    Chairman

Dated:    March 11, 1994                     Dated:    March 9, 1994

                                             ATLANTIC RICHFIELD COMPANY

                                             By:  Anthony G. Fernandes
                                                  An Authorized Representative

                                             Title:    Senior Vice President

                                             Dated:    March 9, 1994









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                                   EXHIBIT A
                                        
                                PROMISSORY NOTE
                                        
     Pursuant to  a Settlement  Agreement of  even date  herewith, Nevada  Power
Company, a  Nevada corporation  ("Nevada Power"),  for  value  received,  hereby
promised to  pay  to  the  order  of  ATLANTIC  RICHFIELD  COMPANY,  a  Delaware
corporation ("ARCO"),  or ARCO's  assigns, the  sum of Twenty-five Million three
Hundred  Ten  Thousand,  Five  Hundred  Fifty-two  Dollars  ($25,310,552.00)  in
immediately available  funds on  or before  June 11,  1994, at  555  Seventeenth
Street, Suite 2100, Denver, Colorado 80202.

     Payment shall  be made  without interest  if made on or before the close of
business on  the thirtieth  day after  execution of  the Settlement Agreement by
Plaintiffs.   If payment is made after the thirtieth day, interest shall be paid
at a  rate of  ten percent  (10%) annually  ($6,934.40 per day), calculated from
April 13, 1994.

     If unpaid,  in whole  or in  part, on June 11, 1994, Nevada Power agrees to
confess judgment  in any  court of competent jurisdiction which ARCO may choose,
in favor  of ARCO and against Nevada Power with interest accruing on said sum as
from April  13, 1994,  at the rate of Ten Percent (10%) per annum.  Nevada Power
hereby consents to jurisdiction and venue in any such court.

     Nevada Power  hereby waives  presentment for  payment,  demand,  notice  of
dishonor and protest of this promissory note.

     This instrument  shall be  governed in all respects by the law of the State
of Utah.

     Any expense  incurred by  ARCO in  the collection  of this  note by suit or
otherwise, including, but not limited to, attorneys' fees and court costs, shall
be borne by Nevada Power.

                                        NEVADA POWER COMPANY

                                        By:  David G. Barneby
                                             An Authorized Representative

                                        Dated:    March 9, 1994