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                                                                  Exhibit 10.1.a

                              BASIC TOLL AGREEMENT
                                     BETWEEN
                      EMPRESA NACIONAL DE ELECTRICIDAD S.A.
                                       AND
                     COMPANIA NACIONAL DE TRANSMISION ELECTRICA S.A.

In Santiago, Chile, on October 23, 2000, between EMPRESA NACIONAL DE
ELECTRICIDAD S.A., hereinafter and indistinctly, ENDESA, represented by its
General Manager, Mr. Hector Lopez Vilaseco, both domiciled in Santiago at Calle
Santa Rosa No 76, Floor 17, and COMPANIA NACIONAL DE TRANSMISION ELECTRICA
S.A., hereinafter and indistinctly referred to as TRANSELEC, represented by its
General Manager, Mr. Guillermo Espinosa Ihnen, both domiciled in Santiago at
Calle Santa Rosa No 76, Floor 9, the following has been agreed:

ONE: PURPOSE.

The purpose of the present contract is to agree on the annual basic toll
payments that ENDESA is to pay to TRANSELEC for its power plants Canutillar
(nominal power of 145.0 MW), El Toro (nominal power of 400.00 MW), Antuco
(nominal power of 300.0 MW), Abanico (nominal power of 136.0 MV), Bocamina
(nominal power of 125.0 MV), Cipreses (nominal power of 101.4 MV), Isla
(nominalo power of 68.0 MV), Sauzal (nominal power of 76.8 MV), Sauzalito
(nominal power of 9.5 MV), Rapel (nominal power of 350.0 MV), Los Molles
(nominal power of 16.0 MV), Huasco (nominal power of 80.23 MV), Diego de Almagro
(nominal power of 23.75 MV), and Taltal (nominal power of 240.0 MW), hereinafter
referred to as ENDESA Power Plants, as of October 23, 2000.

The basic annual payments will entitle ENDESA to upload up to the maximum power
and energy production capacity of the ENDESA Power Plants, which capacities are
indicated in the preceding paragraph, to transmit it, and to download energy and
power by means of the facilities which form part of its area of influence.
ENDESA shall exercise this right in accordance with the provisions provided, to
said effect, by the Economic Load Dispatch Center of the Central Interconnected
System (the CDEC-SIC).

Likewise, such downloads without supplementary payments as ENDESA may make in
the area of influence of each one of its power plants and at all of the
junctions from which, under normal operating conditions of the system, net
physical transmissions occur toward such area of influence, once it has paid the
basic toll, are limited to:

a)    The firm power of the power plant, plus such power as may have been
      contracted with third parties that have paid the basic and supplementary
      tolls necessary for reaching the point of download;

b)    The total capacity of the transmission system involved, without the
      existence of any priority or order of preference in this respect between
      all the power plants that pay the basic toll.


ENDESA - TRANSELEC  Basic Toll Contract                                        1
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c)    At such limits as the CDEC-SIC may establish, in consideration of what is
      provided in Article 198 of the Regulation for the General Electric
      Services Law approved by Supreme Decree No 327 of the Ministry of Mining,
      dated December 12, 1997, hereinafter the Electric Regulation.

TWO: THE AREA OF INFLUENCE

The parties agree that the area of influence of the ENDESA Power Plants is
comprised of the segments that connect the upload buses of such power plants,
which, for the purposes of the present contract , correspond to those indicated
in Exhibit No 1, with the basic energy sub-station of the Central
Interconnected System, SIC. As of the date of signing of the present contract,
the mentioned basic energy sub-station corresponds to the Quillota sub-station
of TRANSELEC, according to the selection of basic energy sub-station contained
in the semi-annual setting of junction prices of April, 2000.

In the event that, in future junction pricing, the basic energy sub-station is
selected at another junction of the system, the extent of the area of influence
of the ENDESA Power Plants will be modified accordingly. Such modification will
govern commencing from the same month of junction pricing originating a change
in the location of the basic energy sub-station.

In line with the above, the parties agree that, as of October 23, 2000, the area
of influence of the ENDESA Power Plants is to be comprised of the segments
indicated in Exhibit No. 1 hereto.

THREE: ANRV + OMC

The parties agree that, during the period between October 23, 2000 and March 31,
2002, the values of the Annual Payment of New Replacement Values plus the
Operation and Maintenance Costs (the ANRV + OMC) for the facilities referred to
above, belonging to the area of influence of the ENDESA Power Plants, are those
indicated in Exhibit No. 1 hereto, expressed in thousands of dollars of the
United States of America of January 1, 1999.

FOUR: PRO-RATA AMOUNTS

The parties agree that the pro-rata amounts for the ENDESA Power Plants for the
October 23, 2000-March 31, 2002 period are those indicated in Exhibit No. 2
hereto.

FIVE: DEFINITION OF THE NEW REPLACEMENT VALUE

For the purposes of the present contract , the New Replacement Value for the
transmission facilities, hereinafter, and indistinctly, the NRV, will be
understood to mean the cost of renewing all of the works, facilities and
physical assets intended for the function of the transmission of electricity.

Renewal is understood to mean the activity of replacing the works, facilities
and physical assets presently in service with others with identical
characteristics. In the event that they are not available on the market, the
respective cost is to be that of the works, facilities and physical assets of
modern technology, and current cost, meant to fulfill the same function with the
same standards of service quality. In the case of the transmission lines, those
existing are considered with respect to the topographical layout, structures,
voltage, number of circuits, and electrical transmission capacity. In the case
of the sub-stations, consideration is given, in addition to the primary control
and protection equipment, to the auxiliary equipment, including that of the
auxiliary services, battery banks and emergency equipment, buildings meant to
house the equipment indicated, land, and general works.

The costs associated with the NRV's for the transmission lines and for the
sub-stations which constitute the area of influence of the ENDESA Power Plants
include the following items, which are


ENDESA - TRANSELEC  Basic Toll Contract                                        2
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set forth solely as examples, without this listing being restrictive:
engineering and design, construction management and inspection, easements and
compensations, supply of imported and domestic equipment and materials with the
respective entry tariffs, port charges and domestic and international freight,
construction and assembly of works and equipment, other financial and
administrative costs such as staggered interest, overhead expenses, and
operating capital.

For purposes of the valuation of the lines, the original copper wire is replaced
by one of aluminum with equivalent characteristics. In the valuation of the
sub-stations, the switches for large volumes of oil, for compressed air, and for
large volumes of SF6 gas have been valued as switches for small volumes of SF6
gas. The synchronous condensers are valued as if they were static condensers.

SIX: OPERATION AND MAINTENANCE COSTS

Operation and maintenance costs (OMC) take into consideration all of the costs
necessary for the adequate maintenance of the facilities and their proper
decentralized operation subordinate to the Zone Operation Centers (ZOC) and to a
Centralized Transmission Dispatch.

The OMC's take into consideration the operating expenses intended for the
planning, execution and control of the operation and maintenance activities,
being latter either preventative, scheduled as corrective, or non scheduled as
corrective, and the expenses and insurance against accidents in buildings and
facilities.

In addition, the OMC's include the costs of capital, of operation, and of
maintenance for the vehicles, for the maintenance equipment, for the
telecommunications systems, for the tools and for instruments necessary for
carrying out the operation and maintenance activities, including the remote
terminal units (RTU), the Zone Operation Centers (ZOC), and the Centralized
Transmission Dispatch. Likewise, the OMC's include costs of capital, of
operation, and of maintenance for the land and buildings, such as workshops,
offices, and warehouses meant for operation and maintenance.

SEVEN: ANNUAL BASIC TOLL PAYMENTS UP TO MARCH 31, 2002

The parties agree that, as of October 23, 2000, and up to March 31, 2002, under
the category of basic ANRV + OMC for its power plants, ENDESA will pay to
TRANSELEC such amount resulting from multiplying the sum of the annual payment
for the new replacement value (ANRV) and the operation and maintenance costs
(OMC) for each one of the facilities of the area of influence of the said power
plants by the pro-rata amount corresponding to said power plants.

As a result of the above, the parties agree that the annual basic toll payments
for the ENDESA Power Plants for the period from October 23, 2000 to March 31,
2002, net of VAT, which ENDESA is to pay to TRANSELEC, are those indicated in
Table No 1 below. These annual payments, which calculation is indicated in
Exhibit No 3 hereto, are expressed in dollars of the United States of America
as of January 1, 1999.


ENDESA - TRANSELEC  Basic Toll Contract                                        3
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                                   Table No. 1
            ANRV + OMC for the ENDESA Power Plants (basic ANRV + OMC)
                        Basic Energy Substation: Quillota
                 Period from October 23, 2000, to March 31, 2002
               Values in thousands of US $ as of January 1, 1999

--------------------------------------------------------------------------------
    Power Plant                              PERIOD
--------------------------------------------------------------------------------
                     October 23, 2000 to March 31,    April 1, 2001 to March 31,
                               2001                           2002
--------------------------------------------------------------------------------
Canutillar                               13,728.76                     13,794.84
--------------------------------------------------------------------------------
Toro-Antuco-Abanico                       8,596.77                      8,964.43
--------------------------------------------------------------------------------
Bocamina                                    256.95                        261.08
--------------------------------------------------------------------------------
Cipreses-Isla                             1,470.08                      1,459.59
--------------------------------------------------------------------------------
Sauzal-Sauzalito                             23.95                        235.86
--------------------------------------------------------------------------------
Rapel                                       882.81                        856.22
--------------------------------------------------------------------------------
Los Molles                                      --                            --
--------------------------------------------------------------------------------
Huasco                                          --                            --
--------------------------------------------------------------------------------
Diego de Almagro                                --                            --
--------------------------------------------------------------------------------
Taltal                                    1,472.93                      1,472.77
--------------------------------------------------------------------------------
              TOTAL:                     26,642.25                     27,044.79
--------------------------------------------------------------------------------

The values contained in Table No 1 above take into consideration that, as of
October 23, 2000 the area of influence of the ENDESA Power Plants extends from
the download bus of the power plant to the Quillota sub-station of TRANSELEC.

EIGHT: ANNUAL BASIC TOLL PAYMENTS COMMENCING FROM APRIL 1, 2002

Starting from April 1, 2002, and until the date when a modification of the
present basic toll contract may start to govern, arising as indicated in Clause
TWELVE, the amount of the basic toll that ENDESA will pay to TRANSELEC will be
calculated by considering the following for each one of the power plants
thereof:

a)    The facilities which comprise the area of influence thereof as established
      by the Board of Directors of the CDEC - SIC in accordance with the
      Electric Regulation Article 176, letter b)

b)    The values of basic tolls per unit of firm power for each segment,
      calculated by the Tolls Administration of the CDEC - SIC, as provided in
      letter h) of Article 182 of the Electric Regulation. For such purposes,
      the NRV's and OMC's indicated in letter d) below will be considered.

c)    The firm power calculated by the Operations Department of the CDEC - SIC
      as indicated in letter f) of Article 181 of the Electric Regulation.

      In the event that the CDEC - SIC has not calculated the firm power of the
      power plants of the SIC, the most recent values of firm power of the
      ENDESA power plants which were in force on such date will be provisionally
      applied.

d)    The New Replacement Values (NRV's) and the Operation and Maintenance Costs
      (OMC's) published by TRANSELEC in the book of same name, July 1999
      edition, duly indexed according to the formulas contained in said
      publication.


ENDESA - TRANSELEC  Basic Toll Contract                                        4
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e)    The calculation of the basic toll for ENDESA will be made on an annual
      basis and the new value will take effect between the months of April of
      each year and March of the following year.

NINE: PAYMENT MODALITY.

The basic ANRV + OMC's will be paid in twelve monthly payments upon accrual each
month, equivalent to multiplying the value of the basic ANRV + OMC indicated for
each period and power plant in Table No. 1 above, or the basic tolls resulting
from applying what is provided in Clause EIGHT, duly indexed as provided in
Clause TEN, by the factor of 0.07974 (seven thousand nine hundred seventy-four
one-hundred-thousandths) and converted into pesos of domestic currency by
employing the exchange rate corresponding to the "observed dollar" referred to
in the first paragraph of No 6, Chapter I, Title I, of the Compendium of
International Currency Exchange Rules published by the Central Bank of Chile, or
such as may replace it in the future, at the average for the month corresponding
to payment. The value Added Tax will be charged separately to the payment thus
stipulated.

TRANSELEC will send the invoice within the first five (5) business days of the
month subsequent to the month to which the charge pertains. ENDESA undertakes to
pay such invoice to the treasury of TRANSELEC in Santiago, in cash, by check,
not crossed, within the banking region of Santiago, or bank sight note, at
latest prior to noon on the sixteenth day of each month subsequent to the month
to which the charge pertains. If such day is a Saturday, Sunday or holiday, the
time due will extend up to noon on the subsequent business day.

Nevertheless, the parties may agree to a different method of payment, which may
be by a bank transfer of funds or deposits into any of the checking accounts of
TRANSELEC. In such case ENDESA must inform TRANSELEC in writing as to the date,
amount, checking account number, and bank through which the payment or deposit
has been made, as well as the number of the invoice or invoices that it has
paid.

In the case of default or simple delay in payment, interest will accrue at the
maximum contractual rate for transactions that are not adjustable of less than
or more than ninety (90) days, as the case may be, from the date when the
default or simple delay took place and up to the date of the actual payment
thereof.

In the event that TRANSELEC delays de delivery of the invoice, ENDESA will be
able to postpone its payment by one day for each day of delay and such
postponement will not be deemed to be a default or simple delay for the purposes
of charging the interest referred to in the preceding paragraph.

TEN: INDEXATION

The parties agree that the monthly payments pertaining to the annual basic toll
amounts for the ENDESA Power Plants are to be indexed semi-annually on January 1
and on July 1 of each year, by multiplying the monthly payment in force for the
previous month by such factor as may result from applying the formula for
indexing tolls detailed in Exhibit No. 4 hereto. For these purposes, the said
indexing factor will be deemed to be rounded off to the fifth decimal.

The first indexation will take place on July 1, 2000 and will cover the period
between January 1, 1999 and June 30, 2000. The parties agree that the indexing
factors corresponding to the first and second semi-annual periods of 1999 and to
the first semi-annual period of 2000 are 0.95896, 0.94468 and 1.04100,
respectively.


ENDESA - TRANSELEC  Basic Toll Contract                                        5
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Whenever a semi-annual indexation of tolls applies, TRANSELEC will prepare and
will send to ENDESA a memorandum of calculation containing, in a detailed and
documented manner, the value of the new monthly payment. The submittal of this
document shall take place five (5) business days before the date of delivery of
the invoices corresponding to the months of January and July of each year.

ELEVEN: SETTLEMENT OF THE VIRT's

The parties agree that they will carry out a monthly settlement, between
themselves, of the valuation of the uploads and downloads per segment (VIRT's)
for each one of the segments indicated in Clause TWO generated in balances of
uploads and downloads made by the CDEC - SIC for each one of the said segments.
The mentioned settlement will be carried out during the month subsequent to the
month to which the settlement pertains, once TRANSELEC has actually received
such amounts from the rest of the members of the CDEC - SIC. In the event that
the CDEC - SIC has not determined the VIRT's or that TRANSELEC has not received
all or part of the VIRT's from the rest of the members of the CDEC - SIC, the
parties may agree on provisional settlements under this category, on account
against final payment.

The amount to be paid for the settlement of the VIRT's will be equal to the VIRT
of each segment multiplied by the pro-rata amount of ENDESA for such segment. If
the amount of the settlement corresponding to the entirety of the segments
indicated in Clause TWO proves to be greater than zero, TRANSELEC will pay such
amount to ENDESA plus VAT; conversely, if the amount of the total settlement
proves to be less than zero, ENDESA will pay the absolute value of such amount,
plus VAT, to TRANSELEC. For purposes of these settlements, if appropriate, the
same interest rate as that applied by the CDEC - SIC.

If in the period subsequent to March 30, 2002, such basic tolls as ENDESA may
pay to TRANSELEC take consideration of the discount of the rate revenues
estimated by the Administration of Tolls of the CDEC - SIC, the latter will be
settled by readjustment between the parties in a monthly manner by applying that
provided for in the present clause, but relating to the discounted rate revenues
values.

TWELVE: PERIOD OF EFFECTIVENESS

The present contract will have an unlimited period of effectiveness commencing
from October 23, 2000.

Notwithstanding what is provided in the previous paragraph, either of the
parties may request from the other party in writing, as of January 1, 2006, a
partial or total revision of the contract.

Revision of the present contract must be anticipated if legal changes arise in
the Statutory Decree with (M) No 1/82, Articles 51, 51A to 51F thereof, in such
manner as to adapt the contract to such legal changes. Revision of the contract
for this reason may be requested by either of the parties and will take effect
once the legal modifications enter into force.

Likewise, if the parties would not reach an agreement with the modifications to
the present contract arising from such general or partial revision as either of
the parties may request commencing from January 1, 2006, within a term of six
months from the date of receipt of such request, the parties agree to submit the
difference to the arbitrating instance provided in Clause EIGHTEEN. The contract
will be modified under the terms pronounced by such arbitrating instance.

In no case will a gap arise in the payments that ENDESA makes to TRANSELEC. In
the event that methodological or regulatory absences of definition exist
deriving from legal modifications, the monthly payments will continue to be made
on the basis of the present contract in a provisional


ENDESA - TRANSELEC  Basic Toll Contract                                        6
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manner subject to adjusted settlement until such time as such absences of
definitions are resolved by mutual agreement between the parties or in
accordance with the procedure established in Clause EIGHTEEN.

The respective modification of the basic toll, whether arising by agreement of
the parties or by decision of the arbitration panel, will govern from the time
when the event causing such revision arises or enters into force, giving rise to
such monthly settlement readjustments as may pertain. The differences will be
paid, if appropriate, by such party as proves to be the debtor, with the
interest current for transactions that are not adjustable of more than or less
than 90 days, as may pertain, within a maximum term of 30 days subsequent to the
time when the contract arises or the arbitration ruling is executed.

THIRTEEN: REVISIONS OF THE BASIC TOLL

The parties agree that, in the period prior to March 31, 2002, the value of the
basic toll under the present contract can solely and exclusively be revised to
incorporate the effects caused by:

a)    The connection of new power plants to the SIC which are not included in
      the Works Plan considered for the calculation of the toll.
b)    Change in the direction of the flow toward the basic energy sub-station of
      the SIC under typical operating conditions.
c)    A failure to materialize, delays or accelerations in projects contemplated
      in the Works Plan considered in the calculation of the toll.
d)    An increase in the capacity of any of the ENDESA Power Plants.
e)    Changes in the capacity of existing power plants.
f)    Disconnection, under the conditions indicated in Article 167 of the
      Electric Regulation, or a change in the point of connection of existing
      power plants.
g)    Modifications to the facilities within the area of influence of the ENDESA
      Power Plants caused by the addition or removal of TRANSELEC facilities.
h)    Acceleration or delay in the transmission works projected in the basic
      toll calculated.

For purposes of what provided in the present clause, reference is to be made to
the conditions employed in the application of the ENDESA / TRANSELEC - COLBUN
arbitration resolution dated January 20, 1999, contained in Exhibit No. 1 to the
report on the contract between TRANSELEC and COLBUN, approved by that Court of
Arbitration on April 15, 1999. Exception is made to the basic toll for the
Taltal power plant, which calculation has been done by employing the bases
included in Exhibit No. 5 hereto.

Revision because of any of the reasons indicated will commence by the interested
party's sending to the other party a written report containing the technical and
economic reasons justifying it. The addressee party of the report will have a
maximum term of 30 consecutive days to analyze and respond to the report.

In the event that the indicated report is rejected, whether expressly or due to
the passage of the term of 30 days without the issuance of a response, it will
be deemed that a disagreement exists with respect to the modification proposed.
In such case, the parties will seek to resolve the differences directly. If
further 30 days elapse and no agreement has been reached, either of the parties
will be able to resort to the arbitration panel provided for in Clause EIGHTEEN
in order to resolve the dispute.

The respective modification to the basic toll, whether arising upon agreement by
the parties or from a decision of the court of arbitration, will govern from the
time when the event causing such revision arises or enters into force, giving
rise to such monthly settlement readjustments as may pertain. The differences
will be paid, if appropriate, by such party that proves to be the debtor, with
the interest


ENDESA - TRANSELEC  Basic Toll Contract                                        7
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current for transactions that are not adjustable of more than or less than 90
days, as may pertain, within a maximum term of 30 days subsequent to the time
when the contract arises or the arbitration ruling is executed.

In no case will a gap arise in the payments that ENDESA makes to TRANSELEC. In
the event that methodological or regulatory absences of definition exist
deriving from legal modifications, the monthly payments will continue to be made
on the basis of the present contract in a provisional manner subject to adjusted
settlement until such time as such absences of definitions are resolved by
mutual agreement between the parties or in accordance with the procedure
established in Clause EIGHTEEN.

Any modification at the facilities which comprise the area of influence or the
pro-rata amounts of the ENDESA Power Plants arising from a revision of the toll
provided in the present clause will, as a result, give rise to the modification
to Exhibits No. 1, No. 2 or No. 3, as appropriate.

The parties agree that the procedure for revising the value of the basic toll
which they have agreed to in the present clause will apply in serious cases
involving significant imbalances in the susceptibility of the contract to
commutation, that is, it will only be applied in instances where it is
ascertained that the economic effect of one or more of the causes defined in
letters a) to h) above, represents an increase or decrease by at least 5% (five
percent) of the value of the annual basic toll payment in force at the time when
the cause or causes giving rise to such revision took place. In order to
determine the percentage of the increase or decrease in the annual payment
indicated, the number of power plants and their diversity in terms of
geographical location have been taken into account.

Notwithstanding what is stated in this clause, in the event that in future
junction pricing, a basic energy sub-station at another junction of the system
is selected, the extent of the area of influence for the ENDESA Power Plants
will be modified accordingly, as provided in Clause TWO hereof.

FORTEEN: LIABILITIES

The liabilities of the contracting parties will be those defined in Statutory
Decree No. 1 of 1982, of the Ministry of Mining, hereinafter the Electric Law,
the Electric Regulation, the manuals and procedures of the CDEC - SIC, and the
modifications or changes to the mentioned legal texts.

TRANSELEC will, at no time, be liable for such damages or losses as ENDESA may
suffer due to a total or partial lack of supply of electrical energy and power,
excessive variations in voltage or frequency, or others caused by technical
failures which may affect the facilities of the Transmission System of TRANSELEC
(SIT), or due to any other event that may interrupt, shut down or disturb
transmissions of energy or power at the facilities of the area of influence of
the ENDESA Power Plants, caused by an act of God or force majeure and, without
the listing below being restrictive, by the following: damage caused by natural
phenomena, earthquakes, lightning, storms, falling trees, floods, and mudflows,
among others.

On its part, ENDESA will in no case, be liable for such losses as TRANSELEC may
suffer due to technical failures or any other event which may interrupt, shut
down or disturb the generating or transmission of energy and power at the ENDESA
Power Plants, caused by an act of God or force majeure. Among other things, an
act of God or force majeure will be deemed as being the occurrence of a
prolonged drought that impedes the normal generation of energy.

FIFTEEN: SUSPENSION OF SERVICE

TRANSELEC may suspend the transmission of energy and power for purposes of
scheduled modification or maintenance activities. Such suspensions will be
planned and scheduled by TRANSELEC upon hearing the opinions on the matter from
the various generating companies


ENDESA - TRANSELEC  Basic Toll Contract                                        8
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affected by such supply interruption. Such suspensions shall be communicated by
TRANSELEC to ENDESA in writing, with at least sixty (60) days in advance.

Service suspensions will be governed by the Electric Law, by the Electric
Regulation, and by the rules and regulations of the CDEC - SIC.

TRANSELEC may also suspend the transmission of energy and power for repair and
emergency purposes. Such suspensions will take place by giving a notice to
ENDESA as far in advance as the circumstances permit.

SIXTEEN: INFORMATION ON OPERATION

TRANSELEC undertakes to send to ENDESA, each time that events affecting the
normal functioning of the transmission facilities of the area of influence of
the ENDESA Power Plants take place, a report indicating the irregularities
and/or service interruptions occurring at such facilities, before 12:00 a.m. on
the day subsequent to the occurrence of the event. The aforementioned report
will indicate the duration of the interruptions that may have arisen at the
facilities in the area of influence of the ENDESA Power Plants and an estimate
of the energy interrupted through such facilities, the day and time when they
occurred. Same report or another supplementary report will indicate the causes
of the irregularities.

SEVENTEEN: AVAILABILITY OF THE SYSTEM

TRANSELEC undertakes to comply with such service quality standards as may be
established by the Electric Law, the Electric Regulation, the manuals and
procedures of the CDEC - SIC, and the modifications or changes to the mentioned
texts, which in no event will be lower than the historical standards existing as
of the date of this contract, measured as the average of the Equivalent
Interruption Time (TEI) from Internal Causes recorded in 1995 to 1999, as
specified in the 1999 annual report by TRANSELEC. Such average TEI for Internal
Causes amounts to 15.9 minutes.

In the event that a failure to comply with this index is detected for two
consecutive years, TRANSELEC undertakes to hire an external technical auditing
firm appointed upon mutual agreement between the parties, that will evaluate and
make recommendations on the operational and maintenance practices followed by
TRANSELEC. The recommendations issued by the auditing firm shall be implemented
by TRANSELEC.

EIGHTEEN: ARBITRATION

Any controversy that may arise between the parties relating to the
interpretation, performance or breach, application, or termination of the
present contract will be resolved by the Court of Arbitration convened as
provided in Article 51 G of Statutory Decree No. 1 of 1982, of the Ministry of
Mining.

It is expressly established that, if one of the parties refuses to designate or
delays in the designation of the arbitrator whom it is responsible for
appointing, the other party may resort to the regular courts of law to proceed
with the appointment thereof. It will be understood that a refusal or delay
exists when the term of twenty (20) days indicated in the third paragraph of the
mentioned Article 51 G has elapsed and the party has not made such designation.

Likewise, the parties leave on record that if the arbitrators do not agree on
the designation of the third arbitrator within the term referred to above, such
designation will be made by the Regular Court of Justice of the Borough of
Santiago, in which case the appointment shall necessarily fall upon an attorney
at law who has been a member of the Supreme Court or the Court of Appeals for
Santiago, or Dean or Director of the University of Chile or Pontifica
Universidad Catolica de Chile Law School.


ENDESA - TRANSELEC  Basic Toll Contract                                        9
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Once arbitration is been convened, the arbitrator shall resolve, as the first
remedy, within a term shorter than 60 days, on the amount that ENDESA must
continue to pay TRANSELEC on a provisional basis, while the controversy is
finally resolved.

NINETEEN: LEGAL CAPACITIES

The legal capacity of Mr. Hector Lopez Vilaseco to represent ENDESA is evidenced
through public deed dated August 31, 2000, executed in the office of the Notary
Public for Santiago, Mr. Fernando Opazo Larrain.

The legal capacity of Mr. Guillermo Espinosa Ihnen to represent TRANSELEC is
evidenced through public deed dated August 18, 1997, executed in the office of
Acting Notary Public for Santiago, Mr. Ismael Ibarra Leniz.

TWENTY: EXHIBITS

The exhibits to this contract, five (5) in total, duly signed by the appearing
parties, are an integral part of this document for all contractual and legal
purposes.

TWENTY-ONE: NUMBER OF COUNTERPARTS

The present contract is signed in four (4) counterparts, two (2) of which are
kept by each one of the parties.

        Hector Lopez Vilaseco               Guillermo Espinosa Ihnen
           GENERAL MANAGER                      GENERAL MANAGER
               ENDESA                              TRANSELEC

                                       s/


ENDESA - TRANSELEC  Basic Toll Contract                                       10