EXHIBIT 2.3

                          WYOMING OIL & MINERALS, INC.

                                LETTER AGREEMENT




                                                                    May 24, 2002



Michael D. Herman
Russell W. McCoy

Dear Mike and Russell:

     This binding  Letter  Agreement  is to set forth the material  terms of the
agreement by Wyoming Oil & Minerals,  Inc. ("WYOG") to purchase from Mike all of
the issued and outstanding capital stock of Blue Star Acid Service, Inc. ("BSA")
and to grant certain consideration to Russell for ongoing services.  Those terms
are as follows:

1.   WYOG shall  purchase  from Mike all of the issued and  outstanding  capital
     stock of BSA as soon as possible (the date of purchase,  the "Closing") and
     shall enter into an  agreement  with  Russell for ongoing  services for the
     following  consideration,  having a total  value of $670,000  ($570,000  to
     Michael D. Herman and $100,000 to Russell McCoy).

     a.   $100,000  payable  in  cash  to  Mike,  receipt  of  which  is  hereby
          acknowledged by Mike Herman;

     b.   the  transfer  by WYOG  to  Mike  at  Closing  of  400,000  shares  of
          restricted  common stock in Dover Petroleum  Corp.,  which the parties
          agree have a current value of $250,000;  Mike shall be responsible for
          obtaining  the actual  certificate  from  Dover,  Dover not yet having
          delivered the shares owned by WYOG to WYOG;  but WYOG shall  cooperate
          as necessary to assist in  effectuating  such transfer;  Mike and WYOG
          hereby agree that neither  shall have any claim  against the other for
          any  increase or decrease  in value of said shares  post-Closing,  and
          that this agreement shall survive the Closing;

     c.   a  promissory  note  payable to Mike in the total  amount of $220,000,
          with 7% interest;  the  principal  amount of $95,000  shall be due 120
          days after Closing,  and the principal amount of $125,000 shall be due
          one year after Closing;  all accrued interest shall be due and payable
          on each  principal  payment  date;  said note  shall be  delivered  at
          Closing;

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     d.   a  promissory  note payable to Russell in the total amount of $50,000,
          with 7% interest;  the  principal  amount of $25,000  shall be due 120
          days after Closing,  and the principal  amount of $25,000 shall be due
          one year after Closing;  all accrued interest shall be due and payable
          on each  principal  payment  date;  said note  shall be  delivered  at
          Closing;  Russell hereby agrees with Mike that he has no claim against
          Mike for any default  under the note,  and that this  agreement  shall
          survive the Closing;

     e.   the  issuance  to  Russell of 25,000  shares of WYOG's  $.01 par value
          restricted  common  stock  valued at $2.00 per share;  Russell  hereby
          agrees with Mike that he has no claim against Mike for any decrease in
          value or other issue with respect to the  preferred or common  shares,
          and that this agreement shall survive the Closing.

2.   WYOG has reviewed Blue Star Acid Service Company's Audited financials dated
     December 31, 2001 and agrees it presents a fair and accurate picture of the
     company's financial position.

3.   The Closing shall occur upon the signing of this agreement and execution of
     the  promissory  notes by both  parties.  Such closing shall occur no later
     than 6-01-02.  For  accounting  purposes only, it is hereby agreed that the
     Letter Agreement shall be effective 4-01-02.


     This Letter  Agreement  is binding,  sets forth all  material  terms of the
agreement  and  supersedes  a previous  Letter  Agreement  dated  3-28-02 by and
between the parties. Please sign and return it no later than 6-01-02.

Agreed and Accepted:                      Wyoming Oil &
                                          Minerals, Inc.


/s/ Michael D. Herman                      By:  /s/ Bill M. Conrad
--------------------------                     -------------------------------
Michael D. Herman                              Bill M. Conrad, President

Date: 5/31/02
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/s/ Russell W. McCoy
--------------------------
Russell W. McCoy

Date:  5/24/02
     ---------------------

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