Exhibit 10.7A
                                                                -------------

Messrs.
COPETRO S.A.
Attn: Juan Carlos Fronza
Leandro N. Alem 822, 11th Floor,
1001 Capital Federal
--------------------

We call your attention in reference to the conversations held between Y.P.F.
S.A. (from now on "YPF"), with address at Av. Pte. Roque Saenz Pena 777 -
Capital Federal, and COPETRO S.A. (from now on "COPETRO"), with address at
Leandro N. Alem 822, 11th Floor - Capital Federal, related to the petroleum 
coke supply tied to the construction of the 2nd kiln at your plant in
Ensenada.

In such regard, the current Note summarizes the agreement between COPETRO and
YPF in what it concerns to the Addenda, related to the Petroleum Coke Supply
Contract celebrated between COPETRO and Yacimientos Carboniferos Fiscales 
Empresa del Estado, on October 24, 1989 (from now on, "the Contract") being
approved by Resolution Nr. 181 of the Secretariat of Energy on December 20,
1989; and handed over to YPF as far as obligations and rights of YCF through
agreement dated March 23, 1992, as stated by Resolution S.H. and M. Nr. 19/92
and Agreement Bill YPF - COPETRO, of March 6 1995, from now on "Agreement
Bill".

ARTICLE ONE:  As of the starting up of the "Second Kiln", which is mentioned
in Article 2 of the present addenda, YPF is obliged to sell and deliver to 
COPETRO who is obliged to buy, receive and pay to YPF, petroleum coke in the 
quantities and conditons specified below:

(i)  CONFIDENTIAL INFORMATION OMITTED under the conditions of "take or pay" 
on COPETRO's behalf, that must comply with the Technical Specifications 
established in "Annex A" of this Addenda. The value of the properties there 
shown will be the rolling average value applied on the total quantities of 
petroleum coke delivered by YPF to COPETRO during the last thirty (30) days.

(ii)  CONFIDENTIAL INFORMATION OMITTED under the following conditions:

(ii.a)  If YPF has CONFIDENTIAL INFORMATION OMITTED of petroleum coke, 
excluding the product from the first cut of the drums (fines), from its
production at the La Plata Refinery, COPETRO will take the total amount of 
said quantity whatever its specifications may be and the price will be 
negotiated between both Parties quarterly.  If both Parties have not reached
an agreement on the price for the following quarter, they are relieved from
their obligations agreed in this point, for such quarter.

<PAGE>
(ii.b) If YPF excluding the product from the first cut of the drums (fines),
has a smaller amount than CONFIDENTAIL INFORMATION OMITTED not have any 
quantity at all of petroleum coke from its La Plata Refinery, COPETRO
will take the total amount of petroleum coke available in said Refinery 
whatever its specifications may be, and YPF will complete the balance up to
CONFIDENTIAL INFORMATION OMITTED of petroleum coke from its Lujan de Cuyo 
Refinery, whatever its specifications may be.  The price of the petroleum
coke delivered to COPETRO will be negotiated quarterly.  If both Parties have
not reached an agreement on the price for the following quarter, they are 
relieved from their obligations agreed in this point, for such quarter.

(ii.c)  In these 2 cases, prior to YPF delivering to COPETRO any of the
petroleum coke from its Lujan de Cuyo Refinery, COPETRO must have taken the
total amount of the petroleum coke available at the La Plata Refinery.  YPF
commits to make its best effort for these quantities to meet the technical 
specs set in the Annex A of this Addenda.

(iii)  "In the event that YPF, after allocating the quantities that - up to a
maximum of CONFIDENTIAL INFORMATION OMITTED in 1999 and up to a maximum of 
CONFIDENTIAL INFORMATION OMITTED in the year 2000 and onwards to the end of 
the duration of the present Addenda - needs to fulfill its commitments with 
3rd parties, should consider disposing of additional production of petroleum 
coke, YPF will communicate to COPETRO the possibility of delivering up to a 
maximum of CONFIDENTIAL INFORMATION OMITTED additional quantities to the ones 
set in the above paragraphs (i) and (ii) on which COPETRO will enjoy an 
absolute priority.  Such communication will be given by YPF to COPETRO with a 
lead time no less than 180 days of the starting of the calendar year in 
question.  COPETRO must notify YPF, within 15 days of receiving said 
communication, if it will take the quantity offered by YPF or a lower quan-
tity.  The quantities offered by YPF and accepted by COPETRO in the terms of 
this paragraph (iii), will also be taken by COPETRO in the "take or pay" 
condition.  YPF commits to make its best effort for the additional quantities 
dealing in this paragraph (iii) to meet the technical specs set in the Annex 
A of this Addenda.

ARTICLE TWO:  The above mentioned clause will be in effect subject to the
following conditions:

(i) that COPETRO starts the construction of the Second Calcining Kiln at its
Plant located in Ensenada, Province of Buenos Aires (from now on the "Second
Kiln") within the six months as from the subscription date of this Addenda,
and

(ii) that the Start Up of the Second Kiln takes place within the two years as
from the starting date of its construction, having COPETRO to notify YPF in a
certified manner with no less than one hundred and eighty (180) days prior to
the start up of the Second Kiln.

<PAGE>

ARTICLE THREE: Both parties acknowledge that the quantities committed in
Article ONE of this Addenda are additional to the quantities mentioned in
point 3.01 of the Contract.  At the same time, as from the date this Addenda
is in effect, the quantities set in the relevant point of the Contract, must
comply with the Technical Specifications of the Annex A of this Addenda.

ARTICLE FOUR:

4.1  The price of the quantities of petroleum coke mentioned in Article 1 of
this Addenda is set by clauses VIII and IX of the Contract, increased by 
CONFIDENTIAL INFORMATION OMITTED United States Dollars with CONFIDENTIAL
INFORMATION OMITTED per MT (US$ CONFIDENTIAL INFORMATION OMITTED /MT).

4.2  As of December 20, 2004 the price of petroleum coke committed in the
Contract, will be set by clauses VIII and IX of the Contract, increased by
CONFIDENTIAL INFORMATION OMITTED United States Dollars per MT (US$ 
CONFIDENTIAL INFORMATION OMITTED /MT).

ARTICLE FIVE: In the event that COPETRO foresees it will not be able to comply
with the conditions mentioned in Article 2 (i) within the periods there 
mentioned, unless Force Majoure reasons, the following Procedure will apply:

5.1 With no less than 60 days prior to the maturity mentioned in Article 2(i)
COPETRO will notify YPF of the impossibility of complying with such time 
limit, requesting an extension.

5.2 When notifying YPF of the impossibility of complying with the time limit
mentioned in Article 2(i) and when requesting an extension, COPETRO will be
able to choose whether to:

                        a) Express reasons for the delay.

                        b) Not express reasons for the delay.

5.3 If COPETRO choose to express the reasons for the delay, YPF can, within
the period of 5 (five) days of receiving said notification as per Clause 5.1,
accept or turn down the request expressing their reasons for turning it down.

If YPF should accept the reasons, the period established in Article 2(i) will
be automatically extended at its maturity for thirty (30) days, and once that
time is up Clause 5.6 will apply.

<PAGE>

If YPF turns down the request, the period established in Article 2(i) will
remain the same falling due in six (6) months as from the date of subscription
of the present Addenda.

5.4 If COPETRO decides not to give any reasons for the delay as per period
established in Article 2(i) the maturity will be automatically extended for
fifteen (15) days, and then the conditions established in Clause 5.6 will
apply.

5.5 In all cases where COPETRO requests and gets an extension, it will be
granted only once and will not be renewed.

5.6 Once the original time limits are up -- if an extension has not been
requsted or granted, and/or time limit not be automatically extended according
to the conditions in Clause 5.4 -- or having fallen due the extensions granted,
if COPETRO has not started the construction of the Second Kiln, YPF will have
the right, unless Force Majoure reasons, to rescind the present Addenda 
without implying any responsibility to either Party.

ARTICLE SIX:  In the event that COPETRO does not comply with the conditions
mentioned in Article 2(ii) within the periods there mentioned, unless Force
Majoure reasons, the following Procedure will apply:

6.1 Having the time limit mentioned in Article 2(ii) expired, COPETRO will be
subject to the conditions of "take or pay" during the period of two (2) months
following the date of maturity and up to CONFIDENTIAL INFORMATION OMITTED
maximum.

6.2 Having the time limit established in Clause 6.1 expired, YPF will be able
to rescind the present Addenda and claim compensation for damages and losses
caused by COPETRO's nonfulfillment.

ARTICLE SEVEN:  Both Parties agree to extend the duration of the present
Contract (including this Addenda) CONFIDENTIAL INFORMATION OMITTED, therefore
annulling the automatic renewal considered in clause 4.02 of Article 4 of the
Contract.  The present extensions will be annulled if COPETRO does not comply
with the conditions mentioned in Article 2 of the present Addenda.  If COPETRO
does not comply with this condition, the Contract will remain valid, as orig-
inally agreed in all its terms and the current Addenda will have no validity
whatsoever, except for its Article 6.

ARTICLE EIGHT:  So as to improve the reception of petroleum coke mentioned in
clause 3.01 of Article 3 of the Contract, the additional quantities mentioned
in this Addenda and those allocated to YPF's exports in the tems outlined in
clauses 10.01 and 10.2 of Article X of the Contract and in the Agreement Bill,
COPETRO will increase the capacity of the railyard, work which has already
started, and that will be completed prior to the start-up of the Second Kiln.

<PAGE>

ARTICLE NINE:

9.1 Should the petroleum coke purchased by COPETRO in the terms of the 
Contract and of this Addenda cannot, for Force Majoure reasons, be destined
for calcining at the Plant in Ensenada, COPETRO will notify YPF in writing
within 96 hours of such event, and give it another destination with previous
agreement and consent in writing by YPF, who cannot deny it without any
justified reason.  No response from YPF within 7 working days will be consid-
ered an approval.

9.2 Both Parties agree in case of Force Majoure reasons, that COPETRO is freed
from its obligation of receiving and acquiring new supplies of product, and
YPF is relieved to sell and deliver any quantity of petroleum coke until the
situation and its consequences are overcome.

9.3 The Party that having a Force Majoure situation fails to notify such event
within 96 hours, will lose its right to do so.

9.4 COPETRO must calcine all the petroleum coke received, except in the case
of Force Majoure, according to the procedure outlined previously, or in the 
case it requested and obtained a written approval from YPF to export it for
its calcination abroad.  For such purpose, request must be made with 90 days
lead time.  YPF will respond within 5 working days of receiving such request,
which cannot be denied without any justified reason.  No response from YPF
will be considered an approval.

10. All points not modified in this Addenda, remain the same as the terms and
conditions mentioned in the Contract and in the Agreement Bill.

<PAGE>
                                     
                                     ANNEX A

                             TECHNICAL SPECIFICATIONS

                                           Rolling average value
                                             of last 30 days -
                                           including the day of
                                            the delivery being
                                            considered - of the
                     Maximum Value for       total quantities
                    Total Daily Quan         received in said
                          Received                period              Norm
------------------------------------------------------------------------------
Volatile matter,
% in weight,
dry basis                  CONFIDENTIAL INFORMATION OMITTED        ASTM-D 4421
------------------------------------------------------------------------------
Ashes at 950o C
% in weight,
dry basis                        "           "         "           ASTM-D 4422
------------------------------------------------------------------------------
Sulphur
(% in weight)                    "           "         "           ASTM-D 3177
------------------------------------------------------------------------------
Vanadium (ppm,
dry basis)                       "           "         "           ASTM-D 5056
------------------------------------------------------------------------------
Nickel (ppm,
dry basis)                       "           "         "           ASTM-D 5056
------------------------------------------------------------------------------
Iron (ppm, dry
basis)                           "           "         "           ASTM-D 5056
------------------------------------------------------------------------------
Silicon (ppm,
dry basis)                       "           "         "           ASTM-D 5056
------------------------------------------------------------------------------
Sodium (ppm,
dry basis)                       "           "         "           ASTM-D 2795
------------------------------------------------------------------------------
Calcium (ppm,
dry basis                        "           "         "           ASTM-D 5056
------------------------------------------------------------------------------
Hardgrove Index                  "           "         "           ASTM-D 5003
------------------------------------------------------------------------------
<PAGE>

                                          Rolling average value
                                            of last 30 days -
                                           including the day of
                                            the delivery being
                                            considered - of the
                     Minimum value for      total quantities
                    total daily quantity    received in said
                          received               period
------------------------------------------------------------------------------
Sizing % retained
in mesh 6,3 mm                CONFIDENTIAL INFORMATION OMITTED
------------------------------------------------------------------------------
                                    NO SHOT COKE 
------------------------------------------------------------------------------


* If the average value of Vanadium (V) is higher than CONFIDENTIAL INFORMATION
OMITTED, but lower than CONFIDENTIAL INFORMATION OMITTED, then the sum of
Calcium (Ca) + Sodium (Na) must be lower than CONFIDENTIAL INFORMATION OMITTED

The offer outlined in this Note will be valie for 3 days.  If within such
period YPF does not receive an objection to the same and COPETRO takes
petroleum coke in the terms of the original contract, as amended by this Note,
the offer will be considered accepted and this Note will be fully valid.

Yours truly,