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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  FORM 10-K/A

[X]  Annual report pursuant to section 13 or 15(d) of the Securities
     Exchange Act of 1934 [ Fee Required ] for the fiscal year ended December
     31, 1996

[ ]  Transition report pursuant to section 13 or 15(d) of the Securities
     Exchange Act of 1934 [No Fee Required] for the transition period from
     __________ to ____________

                         COMMISSION FILE NUMBER 1-11566

                           MARKWEST HYDROCARBON, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)
 
           DELAWARE                                            84-1352233
(State or other jurisdiction of                             (I.R.S. Employer
incorporation or organization)                             Identification No.)
 

             5613 DTC PARKWAY, SUITE 400, ENGLEWOOD, COLORADO 80111
                    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)

       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE:  303-290-8700

Securities registered pursuant to Section 12(b) of the Act:

       TITLE OF EACH CLASS                NAME OF EXCHANGE ON WHICH REGISTERED
       -------------------                ------------------------------------
      Common Stock, $.01 par value        Nasdaq National Market

Securities registered pursuant to Section 12(g) of the Act:  None

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.
                                Yes  X    No 
                                    ---      ---      
                                        
The aggregate market value of voting common stock held by non-affiliates of the
registrant on March 17, 1997 was $48,695,252.

DOCUMENTS INCORPORATED BY REFERENCE
    
The information required by Part III of this Report (Items 10, 11, 12 and 13) is
incorporated by reference from the registrant's proxy statement filed pursuant
to Regulation 14A with respect to the annual meeting of stockholders
scheduled to be held on June 6, 1997.     

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K  or any amendment to
this Form 10-K.  [X]

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ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
         FINANCIAL DISCLOSURE

None.

                                    PART III

ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

ITEM 11.  EXECUTIVE COMPENSATION

ITEM 12.  SECURITY OWNERSHIP AND CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Pursuant to instruction G(3) to Form 10-K, Items 10, 11, 12 and 13 are omitted
because the Company will file a definitive proxy statement (the "Proxy
Statement") pursuant to Regulation 14A under the Securities Exchange Act of 1934
not later than 120 days after the close of the fiscal year.  The information
required by such Items will be included in the definitive proxy statement to be
so filed for the Company's annual meeting of stockholders scheduled for June 6,
1997 and is hereby incorporated by reference.

                                    PART IV

ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

(a) The following documents are filed as part of this report:
 
     (1)  Financial Statements:

          Reference is made to the listing on page 22 for a list of all
          financial statements filed as a part of this report.

     (2)  Financial Statement Schedules:

          None required.

     (3)  Exhibits

3.1       Certificate of Incorporation of MarkWest Hydrocarbon, Inc. (Filed as
          exhibit 3.1 to MarkWest Hydrocarbon, Inc.'s Registration Statement on
          Form S-1, Registration No. 333-09513 and incorporated herein by
          reference).

3.2       Bylaws of MarkWest Hydrocarbon, Inc. (Filed as exhibit 3.2 to
          MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.1      Amended and Restated Reorganization Agreement made as of August 1,
          1996, by and among MarkWest Hydrocarbon, Inc., MarkWest Hydrocarbon
          Partners, Ltd., MWHC Holding, Inc. RIMCO Associates, Inc. and each of
          the limited partners of MarkWest Hydrocarbon Partners, Ltd. (Filed as
          exhibit 10.1 to MarkWest Hydrocarbon, Inc.'s Registration Statement on
          Form S-1, Registration No. 333-09513 and incorporated herein by
          reference).

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10.2      Loan Agreement dated November 20, 1992, among MarkWest Hydrocarbon
          Partners, Ltd., Norwest Bank Denver, National Association,
          individually and as Agent, and First American National Bank  (Filed as
          exhibit 10.21 to MarkWest Hydrocarbon, Inc.'s Registration Statement
          on Form S-1, Registration No. 333-09513 and incorporated herein by
          reference).

10.3      Modification Agreement, dated July 31, 1996, among MarkWest
          Hydrocarbon Partners, Ltd., MarkWest Hydrocarbon, Inc., Norwest Bank
          Colorado, N.A., First American National Bank N M Rothschild and Sons
          Limited and Norwest (Filed as exhibit 10.2 to MarkWest Hydrocarbon,
          Inc.'s Registration Statement on Form S-1, Registration No. 333-09513
          and incorporated herein by reference).

10.4      Amended and Restated Mortgage, Assignment, Security Agreement and
          Financing Statement, dated May 2, 1996, between West Shore Processing
          Company, L.L.C. and Bank of America Illinois  (Filed as exhibit 10.3
          to MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.5      Secured Guaranty, dated May 2, 1996, between West Shore Processing
          Company LLC and Bank of America Illinois  (Filed as exhibit 10.4 to
          MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.6      Security Agreement, dated May 2, 1996, between West Shore Processing
          Company L.L.C. and Bank of America Illinois  (Filed as exhibit 10.5 to
          MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.7      Pledge Agreement, dated May 2, 1996, between West Shore Processing
          Company, L.L.C. and Bank of America Illinois  (Filed as exhibit 10.6
          to MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.8      Participation, Ownership and Operating Agreement for West Shore
          Processing Company, L.L.C. dated May 2, 1996 (Filed as exhibit 10.7 to
          MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.9      Second Amended and Restated Operating Agreement for Basin Pipeline
          L.L.C., dated May 2, 1996  (Filed as exhibit 10.8 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.10     Subordination Agreement, dated May 2, 1996, among MarkWest Michigan
          LLC, Bank of America Illinois, West Shore Processing Company, L.L.C.,
          Basin Pipeline L.L.C., Michigan Energy Company, L.L.C. (Filed as
          exhibit 10.9 to MarkWest Hydrocarbon, Inc.'s Registration Statement on
          Form S-1, Registration No. 333-09513 and incorporated herein by
          reference).

10.11     Gas Treating and Processing Agreement, dated May 1, 1996, between
          West Shore Processing Company, LLC and Shell  Offshore, Inc. (Filed as
          exhibit 10.10 to MarkWest Hydrocarbon, Inc.'s Registration Statement
          on Form S-1, Registration No. 333-09513 and incorporated herein by
          reference).

10.12     Gas Gathering, Treating and Processing Agreement, dated May 2, 1996,
          between Oceana Acquisition Company and West Shore Processing Company,
          LLC  (Filed as exhibit 10.11 to MarkWest Hydrocarbon, Inc.'s
          Registration Statement on Form S-1, Registration No. 333-09513 and
          incorporated herein by reference).

10.13     Gas Gathering, Treating and Processing Agreement, dated May 2, 1996,
          between Michigan Production Company, L.L.C. and West Shore Processing
          Company, LLC(Filed as exhibit 10.12 to 

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          MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.14     Products Exchange Agreements, dated May 1, 1996, with Ferrellgas,
          L.P. (Filed as exhibit 10.13 to MarkWest Hydrocarbon, Inc.'s
          Registration Statement on Form S-1, Registration No. 333-09513 and
          incorporated herein by reference).

10.15     Gas Processing and Treating Agreement, dated March 29, 1996, between
          Manistee Gas Limited Liability Company and Michigan Production
          Company, L.L.C. (Filed as exhibit 10.14 to MarkWest Hydrocarbon,
          Inc.'s Registration Statement on Form S-1, Registration No. 333-09513
          and incorporated herein by reference).

10.16     Processing Agreement (Kenova Processing Plant), dated March 15,
          1995, between Columbia Gas Transmission Corporation and MarkWest
          Hydrocarbon Partners, Ltd. (Filed as exhibit 10.15 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.17     Natural Gas Liquids Purchase Agreement (Cobb Plant), between
          Columbia Gas Transmission Corporation and MarkWest Hydrocarbon
          Partners, Ltd. (Filed as exhibit  10.16to MarkWest Hydrocarbon, Inc.'s
          Registration Statement on Form S-1, Registration No. 333-09513 and
          incorporated herein by reference).

10.18     Purchase and Demolition Agreement Construction Premises, dated March
          15, 1995, between Columbia Gas Transmission Corporation and MarkWest
          Hydrocarbon Partners, Ltd. (Filed as exhibit 10.17 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.19     Purchase and Demolition Agreement Remaining Premises, dated March
          15, 1995, between Columbia Gas Transmission Corporation and MarkWest
          Hydrocarbon Partners, Ltd. (Filed as exhibit 10.18 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.20     Agreement to Design and Construct New Facilities, dated March 165,
          1995, between Columbia Gas Transmission Corporation and MarkWest
          Hydrocarbon Partners, Ltd. (Filed as exhibit 10.19 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.21     Sales Acknowledgment, dated August 8, 1994, NO. 12577, confirming
          sale to Ashland Petroleum Company  (Filed as exhibit 10.20 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.22     Contract for Construction and Lease of Boldman Plant, dated December
          24, 1990, between Columbia Gas Transmission Corporation and MarkWest
          Hydrocarbon partners, Ltd. (Filed as exhibit 10.22 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.23     Natural Gas Liquids Purchase Agreement (Boldman Plant), dated
          December 24, 1990, between Columbia Gas Transmission Corporation and
          MarkWest Hydrocarbon Partners, Ltd. (Filed as exhibit 10.23 to
          MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.24     Natural Gas Liquids Purchase Agreement, dated April 26, 1988,
          between Columbia Gas Transmission Corporation and MarkWest Hydrocarbon
          Partners, Ltd. (Filed as exhibit 10.24 to 

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          MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.25     1996 Incentive Compensation Plan (Filed as exhibit 10.25 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.26     1996 Stock Incentive Plan (Filed as exhibit 10.26 to MarkWest
          Hydrocarbon, Inc.'s Registration Statement on Form S-1, Registration
          No. 333-09513 and incorporated herein by reference).

10.27     1996 Nonemployee Director Stock Option Plan  (Filed as exhibit 10.27
          to MarkWest Hydrocarbon, Inc.'s Registration Statement on Form S-1,
          Registration No. 333-09513 and incorporated herein by reference).

10.28     Form of Non-Compete Agreement between John M. Fox and MarkWest
          Hydrocarbon, Inc.  (Filed as exhibit 10.28 to MarkWest Hydrocarbon,
          Inc.'s Registration Statement on Form S-1, Registration No. 333-09513
          and incorporated herein by reference).

10.29     Sales Acknowledgment by Ashland Petroleum, 54 million gallons of
          Normal Butane, dated September 9, 1996.

10.30     Sales Acknowledgment by Ashland Petroleum, 19.5 million gallons of
          Isobutane, dated September 9, 1996.

10.31     Pipeline Construction and Operating Agreement between Michigan
          Production Company, L.L.C. and West Shore Processing Company, L.L.C.,
          dated October 1, 1996.

10.32     Non-Recourse Loan Agreement between Michigan Production Company,
          L.L.C. and West Shore Processing Company, L.L.C., dated October 1,
          1996.

10.33     First Amendment to Participation, Ownership and Operating Agreement
          for West Shore Processing Company, L.L. C., dated October 1, 1996.

10.34     Option and Agreement to Purchase and Sell Pipeline, dated October 1,
          1996.

10.35     Mortgage, Assignment, Security Agreement and Financing Statement
          from Michigan Production Company, L.L.C. to West Shore Processing
          Company, L.L.C., dated October 22, 1996.

10.36     Amendment to Participation, Ownership and Operating Agreement for
          West Shore Processing Company, L.L.C., dated December 12, 1996.

10.37     Assignment and Bill of Sale by and between Enron Gas Processing
          Company and West Shore Processing Company, L.L.C., dated January 13,
          1997.

11.       Statement regarding computation of per share

21.       List of Subsidiaries of MarkWest Hydrocarbon, Inc.

23.       Consent of Price Waterhouse LLP, independent accountants
    
27.       Financial Data Schedule      

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