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                                                                  Exhibit 10.36

                            [NORTH COAST LETTERHEAD]


March 21, 2003


Omer Yonel

RE:      Management Retention Program

Dear Omer:

The Company recognizes that the possibility of Change in Control can create
uncertainty and distraction among the employees, which may work to the detriment
of the Company and its stockholders. Accordingly, the Board of Directors of the
Company has determined that appropriate steps should be taken to encourage and
incent you to remain in the employ of the Company through any Change in Control
of the Company. A "Change in Control" is as defined in Exhibit A to this letter.

Accordingly, in consideration for your agreement to remain in the employment of
the Company through the date (the "Retention Date") which ends upon the three
month period (a "Stay Period") following the date of this letter, the Company
agrees to pay you within five business days following the Retention Date, and
any succeeding Retention Date as hereinafter provided, an amount equal to 15% of
your annual base salary for 2003 (the "Management Retention Payment"), provided
that you are in the employ of the Company as of the Retention Date. Furthermore,
you and the Company agree that you shall receive a Management Retention Payment
for each successive Stay Period, each with a Retention Date being the last day
of such Stay Period, following the initial Stay Period for a maximum total of
four Stay Periods. The last such Stay Period shall end on the date which is one
year from the date of this letter; provided, however, that in the event of the
occurrence of a Change in Control, the final Stay Period will be determined as
commencing at the date immediately following the end of the prior Stay Period
and ending at the effective date of the Change in Control, and the final
Management Retention Payment will be determined by multiplication of the
Management Retention Payment by a fraction, the numerator of which is the total
number of days in the final Stay Period and the denominator of which is 90 days.

Furthermore, provided that you remain in the employ of the Company and perform
your duties and behave in a manner required to support the interests of the
Company and its stockholders, upon the occurrence of a Change in Control, you
will share in the Management Retention Bonus Pool, as approved by the Board of
Directors of the Company, which shall be paid to all participants upon the
occurrence of a Change in Control. Any Management Retention amounts paid to you
shall be deducted from your share of the Management Retention Bonus Pool and the
balance of your share of the Management Retention Bonus Pool shall be paid to
you within five business days following the Change in Control.



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Nothing contained in this letter agreement changes your employment relationship
with the Company and this is not a contract of employment. In addition, you are
expected to abide by all company policies and standards of conduct applicable to
employees of the Company. In the event your employment is terminated by the
Company without cause, you shall receive a prorated Management Retention Payment
determined in accordance with the second paragraph of this letter, as if a
Change in Control had occurred upon the date of your termination.

In the event that your employment is terminated for cause, you will forfeit your
right to receive any Management Retention Payments to which you would have
otherwise been entitled. Termination for "cause" shall mean:

                  (i) The willful and continued failure by you to perform
         substantially your duties with the Company or one of its affiliates
         (other than for Disability or Good Reason), after a written demand for
         substantial performance is delivered to you by the Board or the Chief
         Executive Officer of the Company which specifically identifies the
         manner in which the Board or Chief Executive Officer believes that you
         have not substantially performed your duties;

                  (ii) Your willfully engaging in conduct demonstrably and
         materially injurious to the Company; or

                  (iii) Conviction of any felony, any crime involving moral
         turpitude, or any crime committed in the conduct of your official
         duties which is materially adverse to the welfare of the Company.

In the event that you voluntarily terminate your employment with the Company
prior to the Retention Date, or any subsequent Retention Date, you will forfeit
your rights to any Management Retention Payment for which you might have been
eligible for the Stay Period during which your termination occurs.

If you are prepared to make the agreement set forth in this letter, please sign
and return the enclosed copy of this letter to the undersigned.

                                      NORTH COAST ENERGY, INC.


                                      By: /s/ Dale E. Stitt
                                          --------------------------------------
                                          Dale E. Stitt, Chief Financial Officer


Accepted and agreed to:


By: /s/ Omer Yonel
    -------------------
      Omer Yonel

Date:  March 21, 2003




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              EXHIBIT A TO MANAGEMENT RETENTION LETTER AGREEMENT

         For purposes of the Management Retention Program, a Change in Control
is defined to occur when:

         1.  The Company is merged, consolidated or reorganized into another
             corporation or entity or nv NUON (or any successor of nv NUON) or
             an affiliate thereof (collectively "NUON") sells or otherwise
             transfers all or part of the outstanding voting securities it holds
             in the Company and as a result thereof immediately after such
             transaction an entity or a group of entities acting in concert
             holds greater ownership than NUON of the corporation or entity
             surviving after such merger, consolidation, reorganization or sale
             of securities, or

         2.  The Company sells or otherwise transfers all or substantially all
             of its assets to another corporation or entity and as a result
             thereof immediately after such transaction an entity or a group of
             entities acting in concert holds greater ownership than NUON of the
             corporation or entity purchasing such assets.