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                                   EXHIBIT 7.0

          ENERGAS RESOURCES, INC. AND POTOMAC STOCK AND ASSET EXCHANGE
                                    AGREEMENT

         This STOCK AND ASSET EXCHANGE AGREEMENT (the "agreement) is made and
entered into this 2nd day of June, 2000, by and among Energas Resources, Inc.
(an Oklahoma based publicly traded Canadian Corporation), Potomac Energy
Corporation (an Oklahoma publicly traded Corporation),

                              W I T N E S S E T H:

         WHEREAS, Potomac Energy Corporation ("PEC") through its wholly owned
subsidiary Potomac Energy (BVI), Ltd. owns a 25% interest in each of the
RosaBlanca Associations and MonteCristo Association contracts as represented
by the attached schedule "A" and desires to exchange its subsidiary Potomac
Energy (BVI), Ltd. and therein the RosaBlanca and MonteCristo Association
Contracts to Energas Resources, Inc. ("Energas") for stock consideration in
Energas, and;

         WHEREAS, PEC owns a 9% interest in the Thomas Oil Refinery owned and
operated by Dolphin Industries, Inc. (an Oklahoma Corporation) as represented
by the attached schedule "B" and desires to exchange its 9% interest to
Energas for stock consideration in Energas, and;

         WHEREAS, Energas desires to exchange its common stock to PEC for
ownership of the above mentioned assets,

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants and agreements herein contained, the parties hereto hereby agree as
follows:

     1.  Energas shall issue to PEC 1,900,000 shares of common stock. This
         stock shall be restricted according the rules and regulations of the
         Canadian Venture Exchange.

     2.  Energas shall issue to PEC 2,000,000 warrants convertible to 2,000,000
         shares of common stock. These warrants shall have a two-year expiration
         period from the date of issue with a strike price for the first year
         at $1.50 U.S. and a strike price for the second year at $1.72 U.S.

     3.  Potomac shall transfer all rights and title and stock in its wholly
         owned subsidiary of Potomac Energy (BVI), Ltd. and all its assets
         therein which are outlined as follows:
         (i) Rosablanca Association Contract.
         (ii) Montecristo Association Contract.

     4.  Potomac shall transfer all rights and title to its 9% interest in
         Dolphin Industries, Inc. and its asset as owner of the Thomas Refinery
         located in Thomas Oklahoma.

     5.  Energas will assume all liabilities and payables associated with
         each of the above assets as itemized on the attached Schedule "C".

This agreement is subject to Board Approval by both companies and regulatory
approval as required.

Nothing in this Agreement is intended to or shall confer upon anyone other than
the Party(ies) hereto any legal or equitable right, remedy or claim. This
Agreement shall be construed in accordance with the laws of the State of
Oklahoma and may be amended or resolved only by a writing executed by the
Party(ies) hereto. This Agreement may be executed in counterparts, which, when
taken together, shall be deemed a single original.

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         IN WITNESS WHEREOF, this Agreement has been executed by or on behalf of
each of the Party(ies) hereto as of the day and year first above written.

Energas Resources, Inc.
                                       /s/ GEORGE G. SHAW
                                       --------------------------------------
                                       Agreed By: George G. Shaw, President


Potomac Energy Corporation             /s/ CARL W. SWAN
                                       --------------------------------------
                                       Agreed By: Carl W. Swan, Chairman