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                 PRELIMINARY COPY -- FOR THE INFORMATION OF THE
                    SECURITIES AND EXCHANGE COMMISSION ONLY.

                               TABLE OF CONTENTS

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<S>                                                                      <C>
INTRODUCTION...........................................................  1
  General..............................................................  1
  Purpose of the Special Meeting.......................................  1
  Record Date, Voting Securities and Quorum............................  2
  Vote Required........................................................  2
  No Appraisal Rights..................................................  2
  Proxy Information....................................................  2
 
THE ENERGY INDUSTRIES SALE PROPOSAL....................................  3
  Background of the Energy Industries Sale Proposal....................  3
  Fairness Opinion of Financial Advisor................................  5
  Recommendation of the Company's Board of Directors...................  7
  Terms of the Energy Industries Sale..................................  7
  Stockholder Approval.................................................  9
  Voting Agreement of Major Stockholder................................  9
  Resolutions Proposed for Adoption by Stockholders.................... 10
  Fees and Expenses.................................................... 10
  No Rights of Appraisal............................................... 10
  Certain Federal Income Tax Consequences.............................. 10
  Financial Information................................................ 11
  Accounting Treatment................................................. 11
  Regulatory Approvals................................................. 11
  Relation to the Cimarron Sale Proposal............................... 11
  Certain Information Concerning Enterra............................... 11
  Business of Energy Industries........................................ 11
 
THE CIMARRON SALE PROPOSAL............................................. 15
  Background of the Cimarron Sale Proposal............................. 15
  Recommendation of the Company's Board of Directors................... 15
  Resolutions Proposed for Adoption by Stockholders.................... 16
  Stockholder Approval................................................. 16
  No Rights of Appraisal............................................... 16
  Financial Information................................................ 16
  Relation to the Energy Industries Sale Proposal...................... 17
  Business of Cimarron................................................. 17
 
SELECTED FINANCIAL DATA................................................ 19
 
UNAUDITED PRO FORMA CONSOLIDATED
FINANCIAL STATEMENTS................................................... 21
 
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS
AND MANAGEMENT......................................................... 24
 
MARKET PRICES OF COMMON STOCK.......................................... 25
 
OTHER MATTERS.......................................................... 25
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