                                                                    Exhibit 99.1

                                   BEFORE THE
                            UNITED STATES OF AMERICA
                      FEDERAL ENERGY REGULATORY COMMISSION

FACT-FINDING INVESTIGATION OF POTENTIAL      )         DOCKET NO. PA02-2-000
MANIPULATION OF ELECTRIC AND                 )
NATURAL GAS PRICES                           )


TO: DONALD J. GELINAS, ASSOCIATE DIRECTOR OF OFFICE OF MARKETS, TARIFFS, AND
RATES

                     RESPONSE OF THE PINNACLE WEST COMPANIES
                    TO COMMISSION'S MAY 8, 2002 DATA REQUEST

     The following  constitutes  the response of Arizona Public Service  Company
("APS") and its affiliates, Pinnacle West Capital Corporation ("PWCC"), Pinnacle
West  Energy  Corporation,  and APS  Energy  Services  Company,  Inc.  ("APSES")
(collectively  the "Pinnacle West Companies") to the  Commission's  Data Request
dated May 8, 2002,  addressed to those sellers of wholesale  electricity  and/or
ancillary  services to the California  Independent  System  Operator ("Cal ISO")
and/or the California Power Exchange ("Cal PX") (the "Data Requests").

     Given  their  geographical  proximity  to  California,  the  Pinnacle  West
Companies have had a long history of trading, extending over some 40 years, with
and in the California  energy markets.  During the period at issue, the Pinnacle
West Companies  were a net buyer of energy from the  California  market and were
compelled to rely in part on the California market, particularly during the peak
summer  season,  to  assure  reliable  electric  service  to the  Pinnacle  West
Companies'  customers.  In fact, in the current  California refund proceeding at

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FERC, SAN DIEGO GAS & ELECTRIC COMPANY, ET. AL., Docket No. EL00-95-045, the Cal
PX has  acknowledged  that the Pinnacle West  Companies are owed a net refund of
$3.9  million  as a result of the total  cost of the  Pinnacle  West  Companies'
purchases from the Cal PX during much of 2000 and 2001.

     It is now  only  too  apparent  that  the  basic  structure  and the  rules
applicable  to  the  California  markets  were  poorly  designed  and,  in  many
instances,  dysfunctional.  Underscheduling and other strategies by utilities in
California are well-documented,  along with their results. The so-called "Enron"
strategies  referred to in the Data Request  indicate that other  strategies may
have had some market impact. Some of these efforts appear to be within the realm
of normal (albeit  aggressive)  trading  activities  associated with commodities
markets,  and in some  cases  may have  been a  beneficial  counterpoint  to the
dramatic underscheduling by the California utilities. Other activities appear to
clearly cross the line, based on the limited information available. For example,
in one instance the Enron  documents  refer to a complaint by APS to the Cal ISO
with respect to Enron buying  non-firm  energy from APS and  reselling it to the
Cal ISO as firm.  APS responded in this instance  promptly by complaining to the
Cal ISO.

     Given the turbulent  California markets at the time, in August of 2000, the
Pinnacle West Companies  approached  Accenture LLP (formerly Andersen Consulting
LLP) to request a broad  overview  for internal  purposes of the  Pinnacle  West
Companies'  California  trading  practices.   Specifically,  the  Pinnacle  West
Companies requested a basic analysis of two questions:  (1) during the Summer of
2000, did APS act within the rules of the California  electric  market,  and (2)
were there any practices that,  while strictly  within the rules,  may have been
perceived by others  (either  rightly or wrongly) as  questionable.  The related

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internal  report,  which is being  provided to FERC on a  confidential  basis as
requested by Accenture, indicates that no evidence of improper conduct was found
during  the  review.  The  report  and  the  letter  from  Accenture  requesting
confidential treatment are attached as Attachments D and E, respectively.

     In  responding  to the  current  Data  Requests,  and as  described  in the
accompanying  affidavit of David A.  Hansen,  Vice  President  of Pinnacle  West
Marketing and Trading for Pinnacle West Capital  Corporation,  the Pinnacle West
Companies conducted a thorough investigation by outside counsel into the trading
activities of their  employees  and agents in the United  States  portion of the
WSCC during the years 2000 and 2001. This investigation  included  interviews of
trading and other personnel and a review of available  documentation  during the
limited time available since the issuance of the data request on May 8, 2002. To
the extent that  additional  documentation  or  information  is discovered  that
warrants  supplementation of this response,  the Pinnacle West Companies will do
so promptly.

     The Pinnacle West Companies are also providing  detailed  spreadsheets with
this response  summarizing  various  transactions  during the period  2000-2001.
Because of the sheer  volume of the  related  supporting  documentation  and the
relatively  short  time frame in which the  Pinnacle  West  Companies  have been
requested to provide responses to the Data Requests,  the underlying data is not
being provided with this response.  Such data will, of course, be made available
for FERC's review whenever requested.  In addition,  the Pinnacle West Companies
have preserved all existing responsive  telephone records since their receipt of
the Data Request  (covering  the period May 8, 2001 through the end of 2001) and
will similarly make these recordings available for FERC's review upon request.

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<PAGE>
     The specific requests for admissions and other requests are set forth below
followed by the Pinnacle West Companies' responses.

I.   REQUESTS FOR ADMISSIONS

          A.1 ADMIT OR DENY: THE COMPANY ENGAGED IN ACTIVITY  REFERRED TO IN THE
     ENRON  MEMORANDA  AS  "EXPORT  OF  CALIFORNIA   POWER"  DURING  THE  PERIOD
     2000-2001, IN WHICH THE COMPANY BUYS ENERGY AT THE CAL PX TO EXPORT OUTSIDE
     OF  CALIFORNIA  IN ORDER TO TAKE  ADVANTAGE  OF THE  PRICE  SPREAD  BETWEEN
     CALIFORNIA  MARKETS  (WHICH  WERE  CAPPED)  AND  UNCAPPED  MARKETS  OUTSIDE
     CALIFORNIA.

          The Pinnacle  West  Companies  deny that they engaged in a strategy to
     export  energy  from  California  in order to take  advantage  of the price
     spread between capped  California  markets and uncapped  markets outside of
     California.  Again, the Pinnacle West Companies have bought energy from and
     sold energy to California markets for decades in order to meet their public
     utility  obligations to provide reliable,  efficient and economical service
     to their customers.  Such buying and selling of energy is a normal function
     of a utility's responsibilities to provide the least cost and most reliable
     delivery  of energy.  This basic fact  remained  true in 2000 and 2001.  As
     stated above,  the Pinnacle West  Companies  purchased  from  California to

                                       4
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     serve APS loads. In this regard, during the period 2000-2001,  the majority
     of the Pinnacle West Companies' Cal PX purchases derived from the fact that
     a shaped  product  could be purchased  from the Cal PX. In contrast,  other
     sellers of firm energy  required the Pinnacle  West  Companies to buy in 16
     hour blocks.  By example,  where the Pinnacle West Companies  believed that
     firm energy was needed for only a few hours during peak periods, they would
     purchase  that  energy  from the Cal PX,  often at a higher  price than the
     average  price per MWhr  offered  by other  sellers  for a 16 hour block of
     energy.  In  addition,  in the  majority of the  Pinnacle  West  Companies'
     purchases  from the Cal PX, the  purchase  price was below the capped price
     and thus the  decision  to  purchase  plainly had nothing to do with capped
     versus uncapped markets.  Moreover,  the Pinnacle West Companies had no way
     of knowing  whether  the energy it  purchased  was  actually  generated  in
     California.

          Consistent  with the above,  on many occasions  purchases were made in
     the  California  market for export to serve the  Pinnacle  West  Companies'
     customers, but were not ultimately needed for those customers.  This energy
     was then resold to others inside and outside of California. Far from taking
     advantage of capped versus uncapped markets,  the revenue the Pinnacle West
     Companies  received  for the  resale of this  energy was less than the cost
     incurred for the purchase from the Cal PX by $9.3 million.

          It  should  also be  noted  that  the  Pinnacle  West  Companies  were
     obligated  under prudent  utility  practices  and, at times,  Department of
     Energy and FERC  orders,  to offer  excess  energy into  California  and/or
     Western  markets.  The  Pinnacle  West  Companies  on occasion may have had

                                       5
<PAGE>
     excess  energy  available  from  California  purchases  that was later sold
     pursuant to the requirements of those orders. Again, in such circumstances,
     the Pinnacle West Companies  could not have engaged in such sales "in order
     to take advantage of the price spread between capped California markets and
     uncapped markets outside of California."

          Although not required by this  request,  the Pinnacle  West  Companies
     have  provided with this  response,  as  Attachments A and B,  spreadsheets
     showing the  purchases of energy from the Cal PX which were later  exported
     out of the state during the period 2000-2001.  These  spreadsheets list the
     date of the purchase, the volume and price of the energy purchased from the
     Cal PX, the delivery point, and, where applicable,  the resale price of the
     energy,  the volume  sold and the  purchaser.  The  detailed  transactional
     documents  from which this data was  obtained  will be made  available  for
     FERC's review upon request.

          A.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     YOUR COMPANY  ENGAGED IN AS PART OF THIS  ACTIVITY,  INCLUDING THE DATES OF
     ALL   PURCHASES   AND   SALES  OF   ENERGY   AND/OR   ANCILLARY   SERVICES,
     COUNTER-PARTIES TO THE TRANSACTIONS,  PRICES AND VOLUMES,  DELIVERY POINTS,
     AND CORRESPONDING CAL ISO SCHEDULES. ALSO, PROVIDE ALL DOCUMENTS THAT REFER
     OR RELATE TO THE ACTIVITY DESCRIBED IMMEDIATELY ABOVE.

          Not applicable.

                                       6
<PAGE>
          B.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON MEMORANDA AS "NON-FIRM EXPORT" DURING THE PERIOD 2000-2001,  IN WHICH
     THE COMPANY GETS A COUNTERFLOW (SCHEDULING ENERGY IN THE OPPOSITE DIRECTION
     OF A CONSTRAINT) CONGESTION PAYMENT FROM THE CAL ISO BY SCHEDULING NON-FIRM
     ENERGY FROM A POINT IN CALIFORNIA TO A CONTROL AREA OUTSIDE OF  CALIFORNIA,
     AND CUTTING THE NON-FIRM ENERGY AFTER IT RECEIVES SUCH PAYMENT.

          The  Pinnacle  West  Companies  deny that they engaged in the activity
     described in B.1. above and the Enron memoranda.

          B.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES
     OF ALL TRANSACTIONS,  CONGESTION  PAYMENTS RECEIVED,  CORRESPONDING CAL ISO
     SCHEDULES, COUNTER PARTIES, AND DELIVERY POINTS. ALSO PROVIDE ALL DOCUMENTS
     THAT REFER OR RELATE TO THE ACTIVITY DESCRIBED IMMEDIATELY ABOVE.

          Not applicable.

          C.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON MEMORANDA AS "DEATH STAR" DURING THE PERIOD  2000-2001,  IN WHICH THE
     COMPANY   SCHEDULES   ENERGY  IN  THE  OPPOSITE   DIRECTION  OF  CONGESTION
     (COUNTERFLOW),  BUT NO ENERGY IS ACTUALLY PUT ONTO THE GRID OR TAKEN OFF OF
     THE GRID. THIS ALLOWS THE COMPANY TO RECEIVE  CONGESTION  PAYMENTS FROM THE
     CAL ISO.

                                       7
<PAGE>
          The  Pinnacle  West  Companies  deny that they engaged in the activity
     described in C.1. above and the Enron memoranda.

          C.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES
     OF ALL  TRANSACTIONS,  ALL TRANSMISSION AND ENERGY  SCHEDULES,  THE COUNTER
     PARTIES, ALL CONGESTION PAYMENTS RECEIVED. ALSO, PROVIDE ALL DOCUMENTS THAT
     REFER OR RELATE TO THE ACTIVITY DESCRIBED IMMEDIATELY ABOVE.

          Not applicable.

          D.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON MEMORANDA AS "LOAD SHIFT" DURING THE PERIOD  2000-2001.  THIS VARIANT
     OF "RELIEVING CONGESTION" INVOLVES SUBMITTING ARTIFICIAL SCHEDULES IN ORDER
     TO RECEIVE INTER-ZONAL CONGESTION PAYMENTS. THE APPEARANCE OF CONGESTION IS
     CREATED BY DELIBERATELY OVER-SCHEDULING LOAD IN ONE ZONE (E.G., NP-15), AND
     UNDER  SCHEDULING  LOAD IN  ANOTHER,  CONNECTING  ZONE (E.G.,  SP-15);  AND
     SHIFTING LOAD FROM A CONGESTED  ZONE TO THE LESS  CONGESTED  ZONE,  THEREBY
     EARNING CONGESTION PAYMENTS FOR REDUCING CONGESTION.

                                       8
<PAGE>
          The  Pinnacle  West  Companies  deny that they engaged in the activity
     described above in D.1. and the Enron memoranda.

          D.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES
     OF ALL TRANSACTIONS, ALL SCHEDULES OF LOAD BY ZONE, AND CONGESTION PAYMENTS
     RECEIVED.  ALSO, PROVIDE ALL DOCUMENTS THAT REFER OR RELATE TO THE ACTIVITY
     DESCRIBED IMMEDIATELY ABOVE.

          Not applicable.

          E.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON MEMORANDA AS "GET SHORTY" DURING THE PERIOD 2000-2001,  ALSO KNOWN AS
     "PAPER  TRADING" OF  ANCILLARY  SERVICES  IN WHICH IT: (I) SELLS  ANCILLARY
     SERVICES IN THE DAY-AHEAD  MARKET;  AND (II) THE NEXT DAY, IN THE REAL-TIME
     MARKET,  THE COMPANY  "ZEROS OUT" THE  ANCILLARY  SERVICES BY CANCELING THE
     COMMITMENT TO SELL AND BUYING ANCILLARY SERVICES IN THE REAL-TIME MARKET TO
     COVER ITS POSITION.  THE PHRASE "PAPER  TRADING" IS USED BECAUSE THE SELLER
     DOES NOT ACTUALLY HAVE THE ANCILLARY SERVICES TO SELL.

          The  Pinnacle  West  Companies  deny that they engaged in the activity
     described in E.1. and the Enron memoranda.

                                       9
<PAGE>
          E.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY  ENGAGED IN AS PART OF THIS TRADING  STRATEGY,  INCLUDING
     THE DATES OF ALL  TRANSACTIONS;  PRICES AND VOLUMES FOR SALES OF  ANCILLARY
     SERVICES IN THE DAY-AHEAD  MARKET;  THE CANCELLATION OF SUCH SALES,  PRICES
     AND VOLUMES FOR THE PURCHASE OF ANCILLARY  SERVICES IN THE REAL-TIME MARKET
     TO COVER THE COMPANY'S POSITION; AND CORRESPONDING SCHEDULES. ALSO, PROVIDE
     ALL DOCUMENTS  THAT REFER OR RELATE TO THE ACTIVITY  DESCRIBED  IMMEDIATELY
     ABOVE.

          Not applicable.

          F.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON MEMORANDA AS "WHEEL OUT" DURING THE PERIOD 2000-2001. KNOWING THAT AN
     INTERTIE IS COMPLETELY  CONSTRAINED (I.E., ITS CAPACITY IS SET AT ZERO), OR
     THAT A LINE IS OUT OF SERVICE,  THE COMPANY  SCHEDULES A TRANSMISSION  FLOW
     OVER THE FACILITY. THE COMPANY ALSO KNOWS THAT THE SCHEDULE WILL BE CUT AND
     IT WILL RECEIVE A CONGESTION PAYMENT WITHOUT ACTUALLY HAVING TO SEND ENERGY
     OVER THE FACILITY.

          The  Pinnacle  West  Companies  deny that they engaged in the activity
     described in F.1. and the Enron memoranda.

          F.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES

                                       10
<PAGE>
     OF  ALL  TRANSACTIONS,   CORRESPONDING  SCHEDULES,   COUNTER  PARTIES,  AND
     CONGESTION  PAYMENTS  RECEIVED.  ALSO,  PROVIDE ALL DOCUMENTS THAT REFER OR
     RELATE TO THE ACTIVITY DESCRIBED IMMEDIATELY ABOVE.

          Not applicable.

          G.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON  MEMORANDA  AS "FAT BOY"  DURING  THE PERIOD  2000-2001  IN WHICH THE
     COMPANY  ARTIFICIALLY  INCREASES LOAD ON THE SCHEDULE IT SUBMITS TO THE CAL
     ISO WITH A CORRESPONDING AMOUNT OF GENERATION.  THE COMPANY THEN DISPATCHES
     THE GENERATION ITS [SIC] SCHEDULES,  WHICH IS IN EXCESS OF ITS ACTUAL LOAD.
     THIS  RESULTS IN THE CAL ISO PAYING THE COMPANY FOR THE EXCESS  GENERATION.
     SCHEDULING  COORDINATORS  THAT SERVE LOAD IN CALIFORNIA  MAY BE ABLE TO USE
     THIS ACTIVITY TO INCLUDES [SIC] THE GENERATION OF OTHER SELLERS.

          The Pinnacle  West  Companies  deny that they engaged in a strategy to
     artificially  increase  their  scheduled  load in  California  to take into
     account the Cal ISO's underestimate of expected load in California in order
     to take  advantage of favorable  movements in real-time ex post prices,  as
     that  strategy  is  detailed  in the Enron  memoranda.  The  Pinnacle  West
     Companies'  overscheduling  during the two year period at issue amounted to
     only 8% of its small  scheduled  California load and was undertaken for the
     reasons outlined below.

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<PAGE>
          Again,  as described in more detail above,  it must be remembered that
     the Pinnacle West  Companies  are net buyers of energy from the  California
     market.  During the period 2000-2001,  as in prior years, the Pinnacle West
     Companies  purchased energy primarily to meet APS's load obligations and in
     order to insure the reliability of service to these load customers.  In the
     event such energy was not used for APS's load,  the Pinnacle West Companies
     would sell the excess energy at a price  determined in the real-time market
     - I.E. as a price taker - and again, ultimately at a significant LOSS.

          In 1999,  APS (and later APSES) began serving a very limited number of
     retail  customers in  California.  During the year 2000, the retail load in
     California  amounted  to an average of only 120 to 140  megawatts,  and far
     less in 2001.  The retail load was scheduled  slightly  above expected load
     for several reasons.  For example, in developing its California retail load
     forecast, the schedules for such customers were typically increased by 4 to
     5  percent  above  expected  load.  This is a  prudent  measure  in that it
     accounts for variations in conditions  which could affect the load forecast
     or the supply of energy,  including  changing weather  conditions,  loss of
     transmission  lines or line losses,  additions of new  facilities by retail
     customers,  the unanticipated outage of a generating facility and uncertain
     load  forecasts  by newly  transferred  retail  customers.  Above all,  the
     Pinnacle West Companies did not want to be "short" in the California market
     and thereby be subject to the increasingly  volatile  imbalance  charges in
     that  market.   Generally,  the  reason  for  using  this  methodology  was
     operational  or  ease  of  execution,  and not  price.  On a few  occasions
     (involving 16 transactions and averaging  approximately only 500 MWhrs) the

                                       12
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     California  retail load  forecast  was  increased to allow the energy to be
     sold at the real-time ex post market  instead of selling the  generation in
     the Cal PX day-of market or the Cal ISO supplemental market.

          In  addition,  a major  portion of the  increase  in  California  load
     involved a contract with the Modesto  Irrigation  District  ("MID") entered
     into on February 9, 1999. Pursuant to that contract,  APS agreed to provide
     MID with a call option on summer  energy  supply  during the months of June
     through October 2000.  Under the contract,  MID could increase in real time
     the amount of energy to be  delivered by APS with four hours notice to APS.
     In order to accommodate  MID's potential call on the energy,  APS increased
     its scheduled load by no more than the  anticipated  hourly call obligation
     with MID, which varied  monthly,  to account for the  possibility  that MID
     would request  additional  energy. If MID, however,  did not request all of
     the  energy  included  in the  forecast,  APS would be paid for the  excess
     generation,  at whatever  price was  established  by the market;  APS was a
     price-taker at all times and utilized this procedure in order to assure the
     contracted supply to a California  customer.  Price was not a factor in the
     use of this methodology for the MID contract.

          The total Pinnacle West Companies  overscheduled  load during 2000 and
     2001 amounted to 76,059 MWhrs, out of an estimated  minimum Cal ISO load of
     500,000,000  MWhrs for that  period.  In other  words,  the  Pinnacle  West
     Companies  overscheduled  load  was  only a  0.0015  share  of  the  energy
     delivered  in the  Cal  ISO for  that  period.  The  details  of the  above
     transactions are included in Attachment C to this response. This Attachment

                                       13
<PAGE>
     consists  of a series of  spreadsheets  showing  the  scheduled  load,  the
     metered  load,  the total  imbalance  and the amount added to the scheduled
     load. They also provide the total settlement  received from the Cal ISO for
     excess  generation.   Detailed  transactional   documents  from  which  the
     spreadsheets were prepared are available for FERC's review.

          G.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES
     OF ALL TRANSACTIONS, CORRESPONDING SCHEDULES, AND PAYMENTS FROM THE CAL ISO
     FOR EXCESS GENERATION (INCLUDING BOTH PRICE AND VOLUMES). ALSO, PROVIDE ALL
     DOCUMENTS THAT REFER OR RELATE TO THE ACTIVITY DESCRIBED IMMEDIATELY ABOVE.

          Not applicable.

          H.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON MEMORANDA AS "RICOCHET," ALSO KNOWN AS "MEGAWATT  LAUNDERING," DURING
     THE PERIOD 2000-2001, IN WHICH THE COMPANY: (I) BUYS ENERGY FROM THE CAL PX
     AND  EXPORTS TO ANOTHER  ENTITY,  WHICH  CHARGES A SMALL FEE;  AND (II) THE
     FIRST  COMPANY  RESELLS  THE  ENERGY  BACK TO THE CAL ISO IN THE  REAL-TIME
     MARKET.

          The  Pinnacle  West  Companies  deny that they engaged in the activity
     described in H.1. and the Enron memoranda.

                                       14
<PAGE>
          H.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES
     FOR ALL  TRANSACTIONS,  NAMES OF  COUNTER  PARTIES  AND  WHETHER  THEY WERE
     AFFILIATES, THE FEES CHARGED, PRICES AND VOLUMES FOR ENERGY THAT WAS BOUGHT
     AND THEN RESOLD.  ALSO,  PROVIDE ALL DOCUMENTS  THAT REFER OR RELATE TO THE
     ACTIVITY DESCRIBED IMMEDIATELY ABOVE.

          Not applicable.

          I.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON  MEMORANDA AS "SELLING  NON-FIRM  ENERGY AS FIRM  ENERGY"  DURING THE
     PERIOD  2000-2001,  IN WHICH THE COMPANY  SELLS OR RESELLS WHAT IS ACTUALLY
     NON-FIRM  ENERGY TO THE CAL PX, BUT CLAIMS THAT IT IS "FIRM"  ENERGY.  THIS
     ALLOWS  THE  COMPANY  TO  RECEIVE  PAYMENT  FROM THE CAL ISO FOR  ANCILLARY
     SERVICES THAT IT CLAIMS TO BE PROVIDING, BUT DOES NOT IN FACT PROVIDE.

          The  Pinnacle  West  Companies  deny that they engaged in the activity
     described in I.1. and the Enron memoranda.

          I.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES
     FOR ALL  TRANSACTIONS,  PRICES AND VOLUMES,  AND  CORRESPONDING  SCHEDULES.
     ALSO,  PROVIDE ALL DOCUMENTS THAT REFER OR RELATE TO THE ACTIVITY DESCRIBED
     IMMEDIATELY ABOVE.

                                       15
<PAGE>
          Not applicable.

          J.1. ADMIT OR DENY: THE COMPANY  ENGAGED IN ACTIVITY  DESCRIBED IN THE
     ENRON  MEMORANDA AS  "SCHEDULING  ENERGY TO COLLECT  CONGESTION  CHARGE II"
     DURING  THE  PERIOD  2000-2001,  IN WHICH  THE  COMPANY:  (I)  SCHEDULES  A
     COUNTERFLOW EVEN THOUGH IT DOES NOT HAVE ANY AVAILABLE GENERATION;  (II) IN
     REAL TIME,  THE CAL ISO  CHARGES THE COMPANY FOR EACH MW THAT IT WAS SHORT;
     AND (III) THE COMPANY  COLLECTS A CONGESTION  PAYMENT  ASSOCIATED  WITH THE
     COUNTERFLOW SCHEDULED.  THIS ACTIVITY IS PROFITABLE WHENEVER THE CONGESTION
     PAYMENT IS GREATER THAN THE CHARGE  ASSOCIATED WITH THE ENERGY THAT WAS NOT
     DELIVERED.

          The  Pinnacle  West  Companies  deny  that they  were  engaged  in the
     activity described in J.1. and the Enron memoranda.

          J.2. IF YOU SO ADMIT,  PROVIDE COMPLETE DETAILS AS TO ALL TRANSACTIONS
     THAT YOUR COMPANY ENGAGED IN AS PART OF THIS ACTIVITY,  INCLUDING THE DATES
     FOR ALL  TRANSACTIONS,  CORRESPONDING  SCHEDULES,  PRICES AND VOLUMES,  AND
     CONGESTION  PAYMENTS  RECEIVED.  ALSO,  PROVIDE ALL DOCUMENTS THAT REFER OR
     RELATE TO THE ACTIVITY DESCRIBED IMMEDIATELY ABOVE.

                                       16
<PAGE>
          Not applicable.

          K.1.  ADMIT OR DENY:  THE COMPANY  ENGAGED IN ANY ACTIVITY  DURING THE
     PERIOD 2000-2001 THAT IS A VARIANT OF ANY OF THE ABOVE-DESCRIBED ACTIVITIES
     OR THAT IS A VARIANT OF, OR USES THE ACTIVITIES KNOWN AS, "INC-ING LOAD" OR
     "RELIEVING CONGESTION," AS DESCRIBED ABOVE.

          The  Pinnacle  West  Companies  deny that they engaged in any activity
     during  the  period  2000-2001  that  is a  variant  of any  of  the  above
     activities.

          K.2. IF YOU SO ADMIT, PROVIDE A NARRATIVE DESCRIPTION OF EACH SPECIFIC
     TIME IN WHICH THE COMPANY  ENGAGED IN SUCH  ACTIVITY  AND PROVIDE  COMPLETE
     DETAILS OF THOSE  TRANSACTIONS,  INCLUDING  THE DATES OF THE  TRANSACTIONS,
     COUNTER  PARTIES,   PRICES  AND  VOLUMES  BOUGHT  OR  SOLD,   CORRESPONDING
     SCHEDULES,   AND  ANY  CONGESTION  PAYMENTS  RECEIVED.  ALSO,  PROVIDE  ALL
     DOCUMENTS THAT REFER TO OR RELATE TO SUCH ACTIVITIES.

          Not applicable.

II.  REQUESTS FOR PRODUCTION OF DOCUMENTS

     A.   PROVIDE  COPIES OF ALL  COMMUNICATIONS  OR  CORRESPONDENCE,  INCLUDING
          E-MAIL MESSAGES,  INSTANT  MESSAGES,  OR TELEPHONE LOGS,  BETWEEN YOUR

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          COMPANY  AND  ANY  OTHER  COMPANY   (INCLUDING   YOUR   AFFILIATES  OR
          SUBSIDIARIES) WITH RESPECT TO ALL OF THE TRADING STRATEGIES  DISCUSSED
          IN  THE  ENRON  MEMORANDA  (BOTH  THE  TEN   "REPRESENTATIVE   TRADING
          STRATEGIES"  AS WELL AS "INC-ING  LOAD" AND  "RELIEVING  CONGESTION").
          THIS REQUEST  ENCOMPASSES ALL  TRANSACTIONS  CONDUCTED AS PART OF SUCH
          TRADING STRATEGIES ENGAGED IN BY YOUR COMPANY AND THE OTHER COMPANY IN
          THE U.S. PORTION OF THE WSCC DURING THE PERIOD 2000-2001.

               Not applicable.

     B.   PROVIDE COPIES OF ALL MATERIAL, INCLUDING, BUT NOT LIMITED TO, OPINION
          LETTERS,  MEMORANDA,  COMMUNICATIONS  (INCLUDING E-MAILS AND TELEPHONE
          LOGS),  OR REPORTS,  THAT ADDRESS OR DISCUSS YOUR COMPANY'S  KNOWLEDGE
          OF, AWARENESS OF, UNDERSTANDING OF, OR EMPLOYMENT OR USE OF ANY OF THE
          TRADING  STRATEGIES  DISCUSSED  IN THE  ENRON  MEMORANDA,  OR  SIMILAR
          TRADING STRATEGIES,  IN THE U.S. PORTION OF THE WSCC DURING THE PERIOD
          2000-2001.  THE SCOPE OF THIS REQUEST  ENCOMPASSES  ALL MATERIAL  THAT
          ADDRESS OR DISCUSS  YOUR  COMPANY'S  KNOWLEDGE  OR  AWARENESS OF OTHER
          COMPANIES'  USE OF  THE  TRADING  STRATEGIES  DISCUSSED  IN THE  ENRON
          MEMORANDA, OR SIMILAR TRADING STRATEGIES,  INCLUDING,  BUT NOT LIMITED
          TO: (I) OFFERS BY SUCH  COMPANIES TO JOIN IN  TRANSACTIONS  RELATED TO
          SUCH  TRADING  STRATEGIES,  REGARDLESS  OF WHETHER  SUCH  OFFERS  WERE

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<PAGE>
          DECLINED OR ACCEPTED; AND (II) POSSIBLE RESPONSES BY YOUR COMPANIES TO
          OTHER  COMPANIES' USE OF SUCH TRADING  STRATEGIES.  TO THE EXTENT THAT
          YOU WISH TO MAKE A CLAIM OF PRIVILEGE  WITH RESPECT TO ANY  RESPONSIVE
          MATERIAL,  PLEASE PROVIDE AN INDEX OF EACH OF THOSE  MATERIALS,  WHICH
          INCLUDES THE DATE OF THE [SIC] EACH  INDIVIDUAL  DOCUMENT,  ITS TITLE,
          ITS RECIPIENT(S)  AND ITS SENDER(S),  A SUMMARY OF THE CONTENTS OF THE
          DOCUMENT, AND THE BASIS OF THE CLAIM OF PRIVILEGE.

               As Enron  noted in the  memoranda  which are the  subject of this
          Data Request,  the Pinnacle  West  Companies are aware of one incident
          occuring during the period  2000-2001 in which Enron sought to sell to
          the  Cal  ISO  non-firm  energy  (purchased  from  the  Pinnacle  West
          Companies) as firm energy. When it learned of Enron's sale, it advised
          the Cal ISO that the  energy it sold to Enron was  non-firm.  Although
          the Pinnacle West  Companies  are making a concerted  effort to locate
          the  related  documents,  the  Pinnacle  West  Companies  have not yet
          located any  documents  regarding  this  incident.  The Pinnacle  West
          Companies  are not aware of any  other  documents  responsive  to this
          request.

III. REQUESTS FOR OTHER INFORMATION

     A.   ON PAGE 2 OF THE  DECEMBER  8, 2000,  ENRON  MEMORANDUM,  THE  AUTHORS
          ALLEGE  THAT  TRADERS  HAVE  LEARNED TO BUILD IN  UNDER-SCHEDULING  OF

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<PAGE>
          ENERGY INTO THEIR  MODELS AND  FORECASTS.  STATE  WHETHER YOUR COMPANY
          BUILT  UNDER-SCHEDULING INTO ANY OF ITS MODELS OR FORECASTS DURING THE
          PERIOD  2000-2001,   AND  PROVIDE  A  NARRATIVE  DESCRIPTION  OF  SUCH
          ACTIVITY.  PROVIDE COPIES OF ALL SUCH MODELS OR FORECASTS  PREPARED BY
          OR RELIED ON BY YOUR  COMPANY  DURING  THE PERIOD  2000-2001  THAT HAD
          UNDER-SCHEDULING BUILT INTO THEM.

               The Pinnacle West Companies did not build  under-scheduling  into
          any of its models or forecasts during the period 2000-2001.

     B.   REFER  TO  THE  DISCUSSION  OF  THE  TRADING  STRATEGY   DESCRIBED  AS
          "RICOCHET"  IN  THE  ENRON  MEMORANDA.   STATE  WHETHER  YOUR  COMPANY
          PURCHASED ENERGY FROM, OR SOLD ENERGY TO, ANY ENRON COMPANY, INCLUDING
          PORTLAND  GENERAL  ELECTRIC  COMPANY,  AS  PART  OF A  "RICOCHET"  (OR
          MEGAWATT LAUNDERING) TRANSACTION DURING THE PERIOD 2000-2001.  PROVIDE
          COMPLETE DETAILS AS TO SUCH  TRANSACTIONS,  INCLUDING THE DATES OF THE
          TRANSACTIONS;  THE NAMES, TITLES, AND TELEPHONE NUMBERS OF THE TRADERS
          AT YOUR COMPANY WHO ENGAGED IN SUCH TRANSACTIONS;  THE PRICES AT WHICH
          YOUR COMPANY BOUGHT AND SOLD SUCH ENERGY (ON A PER TRANSACTION BASIS);
          THE  VOLUMES  BOUGHT AND SOLD (ON A PER  TRANSACTION  BASIS);  AND ALL
          CORRESPONDING SCHEDULES.

               The Pinnacle West Companies did not purchase energy from, or sell
          energy to, any Enron  company,  including  Portland  General  Electric
          Company, as part of a "Ricochet" (or megawatt laundering)  transaction
          during the period 2000-2001.

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