Exhibit
10.23


MARKWEST
ENERGY GP, L.L.C.


INDEMNIFICATION
AGREEMENT


THIS INDEMNIFICATION AGREEMENT (this “Agreement”)
is entered into as of the
          day of
                       ,
20      , by and between MarkWest Energy GP,
L.L.C., a Delaware limited liability company, and MarkWest Energy Partners,
L.P. (the “Partnership”), a Delaware limited partnership (collectively and
severally referred to herein as the “General Partner”), and the undersigned
Director and/or Officer (“Indemnitees”).


RECITALS


A.            The
General Partner is aware that competent and experienced persons are
increasingly reluctant to serve or continue serving as directors or officers of
companies unless they are protected by comprehensive liability insurance and
adequate indemnification due to the increased exposure to litigation costs and
risks resulting from service to such companies that often bear no relationship
to the compensation of such directors or officers.


B.            The statutes and judicial decisions
regarding the duties of directors and officers are often difficult to apply,
ambiguous, or conflicting, and therefore often fail to provide directors and
officers with adequate, reliable knowledge of the legal risks to which they are
exposed or the manner in which they are expected to execute their fiduciary
duties and responsibilities.


C.            The General Partner and the
Indemnitees recognize that plaintiffs often seek damages in such large amounts,
and the costs of litigation may be so great (whether or not the case is
meritorious), that the defense and/or settlement of such litigation can create
an extraordinary burden on the personal resources of directors and officers.


D.            The General Partner believes that it
is unreasonable for its directors, officers and agents and the directors,
officers and agents of its subsidiaries to assume the risk of judgments and
other expenses which may occur in cases in which the director, officer or agent
received no personal benefit or was not culpable.


E.             The General Partner recognizes that
the issues in controversy in litigation against a director, officer or agent of
a corporation such as the General Partner or its subsidiaries are often related
to the knowledge, motives and intent of such director, officer or agent, that
he or she is usually the only witness with knowledge of the essential facts and
exculpating circumstances regarding such matters, and that the long period of
time which usually elapses before the trial or other disposition of such
litigation often extends beyond the time that the director, officer or agent
can reasonably recall such matters and may extend beyond the normal time for
retirement for such director, officer or agent with the result that he or she,
after retirement or in the event of his or her death, his or her spouse, heirs,
executors or administrators may be faced with limited ability and undue
hardship in maintaining an adequate defense, which may discourage such a
director, officer or agent from serving in that position.













F.             The Board of Directors of the
General Partner (the “Board”) has concluded that, to attract and retain
competent and experienced persons to serve as directors and officers of the
General Partner, it is not only reasonable and prudent but necessary to promote
the best interests of the General Partner and its stockholders for the General
Partner to contractually indemnify its directors and certain of its officers in
the manner set forth herein, and to assume for itself liability for expenses
and damages in connection with claims against such directors and officers in connection
with their service to the General Partner as provided herein.


G.            Section 18-108 of the Delaware
Limited Liability Company Act, under which MarkWest Energy GP, L.L.C. is
organized (the “Act”), and Article 9 of the MarkWest Energy GP, L.L.C.’s Amended
and Restated Limited Liability Company Agreement, empowers the MarkWest Energy
GP, L.L.C. to indemnify its members, managers, directors, officers, employees
and agents by agreement and to indemnify persons who serve, at the request of
the General Partner, as the directors, officers, employees or agents of other
corporations or enterprises.


H.            The General Partner desires and has
requested the Indemnitees to serve or continue to serve as a director and/or
officer of the General Partner, and the Indemnitees only is willing to serve,
or to continue to serve, as a director and/or officer of the General Partner if
the Indemnitees is furnished the indemnity provided for herein by the General
Partner.


NOW, THEREFORE, in consideration of the
foregoing premises and the mutual covenants and agreements set forth below, the
parties hereto, intending to be legally bound, hereby agree as follows:


1.             Definitions.  For purposes of this
Agreement, the following terms shall have the corresponding meanings set forth
below:


“Claim”
means a claim or action asserted by a Person in a Proceeding.


 “Covered Entity” means the General Partner,
any subsidiary or affiliate of the General Partner or any other Person for
which Indemnitees is or was or may be deemed to be serving at the request of
the General Partner, or any subsidiary of the General Partner, as a director,
officer, employee, controlling person, agent or fiduciary.


“Disinterested
Director” means, with respect to any determination contemplated by this
Agreement, any Person who, as of the time of such determination, is a member of
the MarkWest Energy GP, L.L.C.’s board of directors but is not a party to any
Proceeding then pending with respect to any Indemnification Event.


“ERISA”
means Employee Retirement Income Security Act of 1974, as amended, or any
similar Federal statute then in effect.


“Exchange
Act” means the Securities Exchange Act of 1934, as amended, or any similar
Federal statute then in effect.


“Expenses”
means any and all direct and indirect fees and costs, retainers, court costs,
transcript costs, fees of experts, witness fees, travel expenses, duplicating,
printing and binding costs, telephone charges, postage and delivery service
fees and all other disbursements or expenses of any type or nature whatsoever reasonably
incurred by Indemnitees (including fees of investment bankers, 



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accountants and, subject to the limitations set forth
in Section 3(c) below, reasonable attorneys’ fees) in connection with or
arising from an Indemnification Event, including, without limitation: (i) the
investigation or defense of a Claim; (ii) being, or preparing to be, a witness
or otherwise participating, or preparing to participate, in any Proceeding;
(iii) furnishing, or preparing to furnish, documents in response to a subpoena or
otherwise in connection with any Proceeding; (iv) any appeal of any judgment,
outcome or determination in any Proceeding (including, without limitation, any
premium, security for and other costs relating to any cost bond, supersedes
bond or any other appeal bond or its equivalent); (v) establishing or enforcing
any right to indemnification under this Agreement (including, without
limitation, pursuant to Section 2(c) below), Delaware law or otherwise,
regardless of whether Indemnitees is ultimately successful in such action,
unless as a part of such action, a court of competent jurisdiction over such
action determines that each of the material assertions made by Indemnitees as a
basis for such action was not made in good faith or was frivolous; (vi) Indemnitees’
defense of any Proceeding instituted by or in the name of the General Partner
under this Agreement to enforce or interpret any of the terms of this Agreement
(including, without limitation, costs and expenses incurred with respect to
Indemnitees counterclaims and cross-claims made in such action); and (vii) any
Federal, state, local or foreign taxes imposed on Indemnitees as a result of
the actual or deemed receipt of any payments under this Agreement, including
all interest, assessments and other charges paid or payable with respect to
such payments.


“General
Partner Action” means a Proceeding in which a Claim has been brought by or in
the name of the General Partner to procure a judgment in its favor.


An “Indemnification
Event” shall be deemed to have occurred if Indemnitees was or is or becomes, or
is threatened to be made, a party to or witness or other participant in, or was
or is or becomes obligated to furnish or furnishes documents in response to a
subpoena or otherwise in connection with, any Proceeding by reason of the fact
that Indemnitees is or was or may be deemed a director, officer, employee,
controlling person, agent or fiduciary of any Covered Entity, or by reason of
any action or inaction on the part of Indemnitees while serving in any such
capacity (including, without limitation, rendering any written statement that
is a Required Statement or is made to another officer or employee of the
Covered Entity to support a Required Statement).


“Independent
Legal Counsel” means an attorney or firm of attorneys designated by the
Indemnitees that is satisfactory to a majority of the Disinterested Directors
(or, if there are no Disinterested Directors, the MarkWest Energy GP, L.L.C.’s
board of directors) that is experienced in matters of corporate law and neither
presently is, nor in the twenty-four (24) months prior to such designation has
been, retained to represent: (i) the General Partner or Indemnitees in any
matter material to either such party, or (ii) any other party to the Proceeding
giving rise to a claim for indemnification hereunder.


“Losses”
means any and all losses, claims, damages, liabilities, judgments, fines,
penalties, settlement payments, awards and amounts of any type whatsoever
incurred by Indemnitees in connection with or arising from an Indemnification
Event.


“Organizational
Documents” means any and all organizational documents, charters or similar
agreements or governing documents, including, without limitation (i) with
respect to a corporation, its certificate of incorporation and bylaws, (ii)
with respect to a limited liability company, its operating agreement, and (iii)
with respect to a limited partnership, its partnership agreement.



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“Person”
means an individual, a partnership, a corporation, a limited liability company,
an association, a joint stock company, a trust, a joint venture, an
unincorporated organization or other enterprise or government or agency or
political subdivision thereof.


“Proceeding”
means any threatened, pending or completed claim, action, suit, proceeding,
arbitration or alternative dispute resolution mechanism, investigation (formal
or informal), inquiry, administrative hearing, appeal or any other actual,
threatened or completed proceeding, whether brought in the right of a Covered
Entity or otherwise and whether of a civil (including intentional or
unintentional tort claims), criminal, administrative, arbitrative or
investigative nature.


“Required
Statement” means a written statement of a Person that is required to be, and
is, filed with the SEC regarding the design, adequacy or evaluation of a
Covered Entity’s internal controls or the accuracy, sufficiency or completeness
of reports or statements filed by a Covered Entity with the SEC pursuant to
federal law and/or administrative regulations, including without limitation,
the certifications contemplated by Sections 302 and 906 of the Sarbanes-Oxley
Act of 2002, as amended, or any rule or regulation promulgated pursuant
thereto.


“Reviewing
Party” means, with respect to any determination contemplated by this Agreement,
any one of the following: (i) a majority vote of a quorum consisting of the
Disinterested Directors; (ii) a committee consisting solely of Disinterested
Directors, even if such Persons would not constitute a quorum of MarkWest
Energy GP, L.L.C.’s board of directors, so long as such committee was
designated by a majority of the Disinterested Directors; (iii) in the absence
of any Disinterested Directors and upon the written consent of Indemnitees,
MarkWest Energy GP, L.L.C.’s Class A Member’s disinterested directors; or (iv)
Independent Legal Counsel (in which case, any determination shall be evidenced
by the rendering of a written opinion).


“SEC”
means the Securities and Exchange Commission.


“Securities
Act” means the Securities Act of 1933, as amended, or any similar Federal
statute then in effect.


2.             Indemnification.


(a)           Indemnification of Losses and
Expenses.  If an Indemnification
Event has occurred, then, subject to Section 9 below, the General Partner shall
indemnify and hold harmless Indemnitees, to the fullest extent permitted by
law, against any and all Losses and Expenses, provided the Indemnitees acted in
good faith and in a manner Indemnitees reasonably believed to be in, or not
opposed to, the best interests of the General Partner, and, with respect to any
criminal Proceeding, had no reasonable cause to believe Indemnitees’ conduct
was unlawful.  The termination of any
Proceeding by judgment, court order, settlement or conviction or on plea of
nolo contendere, or its equivalent, shall not, of itself, create a presumption
that Indemnitees (i) did not act in good faith in a manner which he reasonably
believed to be in, or not opposed to, the best interests of the General
Partner, or (ii) with respect to any criminal Proceeding, had reasonable cause
to believe that Indemnitees’ conduct was unlawful.  Any indemnification provided for herein shall
be made no later than forty-five (45) days after receipt by the General Partner
of the Notice as required by Section 3(a) below and subject additionally to
Section 4 below.



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(b)           Limitation with Respect to General
Partner Actions. Notwithstanding the foregoing, the General Partner shall
not indemnify and hold harmless Indemnitees with respect to any Losses (as
opposed to Expenses) in connection with or arising from any General Partner
Action.  Furthermore, the General Partner
shall not indemnify and hold harmless Indemnitees with respect to any Expenses
in connection with or arising from any General Partner Action as to which the
Indemnitees shall have been finally adjudged to be liable to the General
Partner by a court of competent jurisdiction due to Indemnitees’ gross
negligence or willful misconduct of a culpable nature in the performance of
Indemnitees’ duties to the General Partner, unless, and then only to extent
that, any court in which such General Partner Action was brought shall
determine upon application that, despite the adjudication of liability, but in
view of all the circumstances of the case, the Indemnitees is fairly and
reasonably entitled to Expenses for such indemnification as such court shall
deem proper.


(c)           Advancement of Expenses.  The General Partner shall advance Expenses to
or on behalf of Indemnitees as soon as practicable, but in any event not later
than 20 days after written request therefore by Indemnitees which request shall
be accompanied by vouchers, invoices or similar evidence documenting in
reasonable detail the Expenses incurred or to be incurred by Indemnitees.  The Indemnitees hereby undertakes to repay
such amounts advanced only if, and to the extent that, it shall ultimately be
determined that Indemnitees is not entitled to be indemnified by the General
Partner as authorized under Delaware law. 
In the event that the General Partner fails to pay expenses as incurred
by Indemnitees as required by this paragraph, Indemnitees may seek mandatory
injunctive relief from any court having jurisdiction to require the General
Partner to pay expenses as set forth in this paragraph.  If Indemnitees seeks mandatory injunctive
relief pursuant to this paragraph, it shall not be a defense to enforcement of
the General Partner’s obligations set forth in this paragraph that Indemnitees
has an adequate remedy at law for damages.


(d)           Contribution.  If, and to the extent, the indemnification of
Indemnitees provided for in Section 2(a) above for any reason is held by a
court of competent jurisdiction not to be permissible for liabilities arising
under Federal securities laws or ERISA, then the General Partner, in lieu of
indemnifying Indemnitees under this Agreement, shall contribute to the amount
paid or payable by Indemnitees as a result of such Losses or Expenses (i) in
such proportion as is appropriate to reflect the relative benefits received by
the Covered Entities and all officers, directors or employees of the Covered
Entities other than Indemnitees who are jointly liable with Indemnitees (or
would be if joined in such Proceeding), on the one hand, and Indemnitees, on
the other hand, or (ii) if the allocation provided by clause (i) above is not
permitted by applicable law, in such proportion as is appropriate to reflect
not only the relative benefits referred to in clause (i) above but also the
relative fault of the Covered Entities and all officers, directors or employees
of the Covered Entities other than Indemnitees who are jointly liable with
Indemnitees (or would be if joined in such Proceeding), on the one hand, and
the Indemnitees, on the other hand, in connection with the action or inaction
that resulted in such Losses or Expenses, as well as any other relevant
equitable considerations.  The relative
fault of the Covered Entities and all officers, directors or employees of the
Covered Entities other than Indemnitees who are jointly liable with Indemnitees
(or would be if joined in such Proceeding), on the one hand, and Indemnitees,
on the other hand, shall be determined by reference to, among other things, the
degree to which their actions were motivated by intent to gain personal profit
or advantage, the degree to which their liability is primary or secondary, and
the degree to which their conduct is active or passive.  No Person found guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any person who was not found guilty of
such fraudulent misrepresentation.



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(e)           Actions where Indemnitees is
Deceased.  If an Indemnification
Event has occurred, and if prior to, during the pendency of or after completion
of a Proceeding Indemnitees dies, the General Partner shall indemnify and hold
harmless Indemnitees’ heirs, executors and administrators against any and all
Expenses and Losses to the extent Indemnitees would have been entitled to
indemnification pursuant to Sections 2(a) above if Indemnitees were still
alive.


3.             Indemnification
Procedures.


(a)           Notice of Indemnification Event.  Indemnitees shall give the General Partner
notice as soon as practicable of any Indemnification Event of which Indemnitees
becomes aware, provided that any failure to so notify the General Partner shall
not relieve the General Partner of any of its obligations under this Agreement,
except if, and then only to the extent that, such failure increases the
liability of the General Partner under this Agreement.  In addition, Indemnitees shall give the
General Partner such information and cooperation as it may reasonably require
and as shall be within Indemnitees’ power.


(b)           Notice to Insurers.  If, at the time the General Partner receives
notice of an Indemnification Event pursuant to Section 3(a) above, the General
Partner has liability insurance in effect which may cover such Indemnification
Event, the General Partner shall give prompt written notice of such
Indemnification Event to the insurers in accordance with the procedures set
forth in each of the applicable policies of insurance.  The General Partner shall thereafter take all
necessary or desirable action to cause such insurers to pay, on behalf of
Indemnitees, all amounts payable as a result of such Indemnification Event in
accordance with the terms of such policies; provided that nothing in this
Section 3(b) shall affect the General Partner’s obligations under this
Agreement or the General Partner’s obligations to comply with the provisions of
this Agreement in a timely manner as provided.


(c)           Selection of Counsel.  If the General Partner shall be obligated
hereunder to pay or advance Expenses or indemnify Indemnitees with respect to
any Losses, the General Partner shall be entitled to assume the defense of any
related Claims, with counsel selected by the General Partner and approved by
the Indemnitees in Indemnitees’ reasonable discretion, upon the delivery to
Indemnitees of written notice of its election so to do.  After the retention of such counsel by the
General Partner, the General Partner will not be liable to Indemnitees under
this Agreement for any fees of other counsel subsequently incurred by
Indemnitees with respect to the defense of such Claims; provided that: (i)
Indemnitees shall have the right to employ counsel in connection with any such
Claim at Indemnitees’ expense; and (ii) if (A) the employment of counsel by
Indemnitees has been previously authorized by the General Partner, (B) counsel
for Indemnitees shall have provided the General Partner with written advice
that there may reasonably be expected to exist a conflict of interest between
the General Partner and Indemnitees in the conduct of any such defense, or (C)
the General Partner shall not have in fact retained counsel to assume the
defense or shall not continue to retain such counsel to defend such Claim, then
the fees and expenses of Indemnitees’ counsel shall be at the expense of the
General Partner. The General Partner may not settle or compromise any claim or
consent to the entry of any judgment with respect to which indemnification is
being sought hereunder without the prior written consent of the Indemnitees
(such consent not to be unreasonably withheld).



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4.             Determination of Right to
Indemnification.


(a)           Successful Proceeding.  To the extent Indemnitees has been
successful, on the merits or otherwise, in defense of any Proceeding referred
to in Sections 2(a) or 2(b), the General Partner shall indemnify Indemnitees
against Losses and Expenses incurred by him in connection therewith.  If Indemnitees is not wholly successful in
such Proceeding, but is successful, on the merits or otherwise, as to one or
more but less than all Claims in such Proceeding, the General Partner shall
indemnify Indemnitees against all Losses and Expenses actually or reasonably
incurred by Indemnitees in connection with each successfully resolved Claim.


(b)           Other Proceedings.  In the event that Section 4(a) is
inapplicable, the General Partner shall nevertheless indemnify Indemnitees,
unless, but then only to the extent that, a Reviewing Party chosen pursuant to
Section 4(c) determines that Indemnitees has not met the applicable standard of
conduct set forth in Sections 2(a) or 2(b), as applicable, as a condition to
such indemnification.


(c)           Reviewing Party Determination.
No such indemnification shall be made, however, unless and until in each
specific case there has been a determination that Indemnitees has met the
applicable standard of conduct set forth in Sections 2(a) or 2(b), as
applicable.  As a condition to any such
indemnification, a Reviewing Party chosen by MarkWest Energy GP, L.L.C.’s board
of directors shall make such determination, subject to the following:


(i)            A Reviewing Party so chosen shall
act in good faith to assure Indemnitees a complete opportunity to present to
such Reviewing Party Indemnitees’ case that Indemnitees has met the applicable
standard of conduct.


(ii)           Indemnitees shall be deemed to have
acted in good faith if Indemnitees’ action is based on the records or books of
account of a Covered Entity, including, without limitation, its financial
statements, or on information supplied to Indemnitees by the officers or
employees of a Covered Entity in the course of their duties, or on the advice
of legal counsel for a Covered Entity or on information or records given, or
reports made, to a Covered Entity by an independent certified public accountant
or by an appraiser or other expert selected with reasonable care by a Covered
Entity.  In addition, the knowledge
and/or actions, or failure to act, of any director, officer, agent or employee
of a Covered Entity shall not be imputed to Indemnitees for purposes of
determining the right to indemnification under this Agreement.  Whether or not the foregoing provisions of
this Section 4(c)(ii) are satisfied, it shall in any event be presumed that
Indemnitees has at all times acted in good faith and in a manner Indemnitees
reasonably believed to be in or not opposed to the best interests of the
General Partner.  Any Person seeking to
overcome this presumption shall have the burden of proof and the burden of
persuasion, by clear and convincing evidence.


(iii)          If a Reviewing Party chosen pursuant
to this Section 4(c) shall not have made a determination whether Indemnitees is
entitled to indemnification within forty-five (45) days after receipt by the
General Partner of the request therefore, the requisite determination of
entitlement to indemnification shall be deemed to have been made and
Indemnitees shall be entitled to such indemnification, absent (A) a
misstatement by Indemnitees of a material fact, or an omission of a material
fact necessary to make Indemnitees’ statement not materially misleading, in
connection with the request for indemnification, or (B) a prohibition of such
indemnification under applicable law; provided, however, that such 45-day
period may be extended for a reasonable time, not to exceed an additional
fifteen (15) days, if the Reviewing Party in good faith requires such
additional time for 



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obtaining or evaluating documentation and/or
information relating thereto; and provided, further, that the foregoing
provisions of this Section 4(c)(iii) shall not apply if (I) the determination
of entitlement to indemnification is to be made by the stockholders of MarkWest
Energy GP, L.L.C., (II), a special meeting of stockholders is called by the
board of directors of MarkWest Energy GP, L.L.C. for such purpose with thirty
(30) days after the stockholders are chosen as the Reviewing Party, (III) such
meeting is held for such purpose within sixty (60) days after having been so
called, and (IV)such determination is made thereat.


(iv)          Change in Control.  If MarkWest Energy GP, L.L.C., the
Partnership, or MarkWest Energy GP, L.L.C.’s Class A Member, MarkWest
Hydrocarbon, Inc. (the “Company”) under goes a Change in Control, the Reviewing
Party shall be the Independent Legal Counsel. 
The General Partner agrees that if there is such a Change in Control,
then with respect to all matters thereafter arising concerning the rights of
Indemnitees to Indemnification under this Agreement or any other agreement or
under MarkWest Energy GP, L.L.C.’s Limited Liability Company Agreement as now
or hereafter in effect, Independent Legal Counsel shall be selected by
Indemnitees and approved by the General Partner (which approval shall not be
unreasonably withheld).  Such counsel,
among other things, shall render its written opinion to the General Partner and
Indemnitees as to whether and to what extent Indemnitees would be permitted to
be indemnified under applicable law and this Agreement and the General Partner
agrees to abide by such opinion.  The
General Partner agrees to pay the reasonable fees of the Independent Legal
Counsel referred to above and to fully indemnify such counsel against any and
all expenses (including attorneys’ fees), claims, liabilities and damages
arising out of or relating to this Agreement or its engagement pursuant hereto.


For
purposes of this Section 4(c)(iv), a “Change in Control” shall mean (a) a
dissolution or liquidation of  a Person,
or (b) a consolidation or merger of a Person with or into any other corporation
other entity or person, or any other corporate reorganization, in which the
equity holders of the affected Person immediately prior to such consolidation,
merger or reorganization, own less than 50% of the affected Person’s voting
power immediately after such consolidation, merger or reorganization; provided, however, that a “Change of Control” shall not
include (i) any transaction with an Affiliate or Affiliates of the Company or
any consolidation or merger effected exclusively to change the domicile of the
Company or (ii) the acquisition by John M. Fox, directly or indirectly, of
beneficial ownership of more than 50% of the voting power of the Company.


(d)           Appeal to Court.  Notwithstanding a determination by a
Reviewing Party chosen pursuant to Section 4(c) that Indemnitees is not
entitled to indemnification with respect to a specific Claim or Proceeding (an “Adverse
Determination”), Indemnitees shall have the right to apply to the Court of
Chancery of Delaware, the court in which that Claim or Proceeding is or was
pending or any other court of competent jurisdiction for the purpose of
enforcing Indemnitees’ right to indemnification pursuant to this Agreement,
provided that Indemnitees shall commence any such Proceeding seeking to enforce
Indemnitees’ right to indemnification within one (1) year following the date
upon which Indemnitees is notified in writing by the General Partner of the
Adverse Determination.  In the event of
any dispute between the parties concerning their respective rights and
obligations hereunder, the General Partner shall have the burden of proving
that the General Partner is not obligated to make the payment or advance
claimed by Indemnitees.



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(e)           Presumption of Success.  The General Partner acknowledges that a
settlement or other disposition short of final judgment shall be deemed a
successful resolution for purposes of Section 4(a) if it permits a party to
avoid expense, delay, distraction, disruption or uncertainty.  In the event that any Proceeding to which
Indemnitees is a party is resolved in any manner (other than by adverse
judgment against Indemnitees) including, without limitation, settlement of such
Proceeding with or without payment of money or other consideration, it shall be
presumed that Indemnitees has been successful on the merits or otherwise in
such Proceeding. Anyone seeking to overcome this presumption shall have the
burden of proof and the burden of persuasion, by clear and convincing evidence.


(f)            Expenses Related to this
Agreement.  Notwithstanding any other
provision in this Agreement to the contrary, the General Partner shall
indemnify Indemnitees against all Expenses incurred by Indemnitees in
connection with any Proceeding under this Section 4 involving Indemnitees
and against all Expenses incurred by Indemnitees in connection with any other
Proceeding between the General Partner and Indemnitees involving the
interpretation or enforcement (subject to Section 10) of the rights of
Indemnitees under this Agreement unless a court of competent jurisdiction finds
that each of the claims and/or defenses of Indemnitees in any such Proceeding
was frivolous or made in bad faith.


5.             Additional
Indemnification Rights; Non-exclusivity.


(a)           Scope. The General Partner
hereby agrees to indemnify Indemnitees to the fullest extent permitted by law,
even if such indemnification is not specifically authorized by the other
provisions of this Agreement or any other agreement, the Organizational
Documents of any Covered Entity or by applicable law.  In the event of any change after the date of
this Agreement in any applicable law, statute or rule which expands the right
of an Delaware corporation or other entity to indemnify a member of its board
of directors or an officer, employee, controlling person, agent or fiduciary,
it is the intent of the parties hereto that Indemnitees shall enjoy by this
Agreement the greater benefits afforded by such change. In the event of any
change in any applicable law, statute or rule which narrows the right of an
Delaware corporation or other entity to indemnify a member of its board of
directors or an officer, employee, controlling person, agent or fiduciary, such
change, to the extent not otherwise required by such law, statute or rule to be
applied to this Agreement, shall have no effect on this Agreement or the
parties rights and obligations hereunder except as set forth in Section 9(a)
hereof.


(b)           Non-exclusivity.  The rights to indemnification, contribution
and advancement of Expenses provided in this Agreement shall not be deemed
exclusive of, but shall be in addition to, any other rights to which
Indemnitees may at any time be entitled under the Organizational Documents of
any Covered Entity, any other agreement, any vote of stockholders or
Disinterested Directors, the laws of the State of Delaware or otherwise.  Furthermore, no right or remedy herein
conferred is intended to be exclusive of any other right or remedy, and every
other right and remedy shall be cumulative and in addition to every other right
and remedy given hereunder or now or hereafter existing at law or in equity or
otherwise.  The assertion of any right or
remedy hereunder or otherwise shall not prevent the concurrent assertion of any
other right or remedy.  The rights to indemnification,
contribution and advancement of Expenses provided in this Agreement shall
continue as to Indemnitees for any action Indemnitees took or did not take
while serving in an indemnified capacity even though Indemnitees may have
ceased to serve in such capacity.



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6.             No
Duplication of Payments.


The
General Partner shall not be liable under this Agreement to make any payment of
any amount otherwise identifiable hereunder, or for which advancement is
provided hereunder, if and to the extent Indemnitees has otherwise actually
received such payment, whether pursuant to any insurance policy, the
Organizational Documents of any Covered Entity or otherwise (but specifically
excluding any payment received by the Indemnitees from any insurance policy
maintained by or for the benefit of such Indemnitees (other than the General
Partner) so long as Indemnitees does not by virtue thereof actually retain
duplicative payments).


7.             Mutual
Acknowledgement.


Both
the General Partner and Indemnitees acknowledge that, in certain instances,
Federal law or public policy may override applicable state law and prohibit the
General Partner from indemnifying its directors and officers under this
Agreement or otherwise.  For example, the
General Partner and Indemnitees acknowledge that the SEC has taken the position
that indemnification is not permissible for liabilities arising under certain
Federal securities laws, and Federal legislation prohibits indemnification for
certain ERISA violations.  Indemnitees
understands and acknowledges that the General Partner has undertaken, or may be
required in the future to undertake, with the SEC to submit the question of
indemnification to a court in certain circumstances for a determination of the
General Partner’s right under public policy to indemnify Indemnitees, and any
right to indemnification hereunder shall be subject to, and conditioned upon,
any such required court determination.


8.             Liability Insurance.


(a)           Maintenance of D&O Insurance.  The General Partner hereby covenants and agrees
that, so long as Indemnitees shall continue to serve as an agent of the General
Partner and thereafter so long as Indemnitees shall be subject to any possible
proceeding by reason of the fact that Indemnitees was an agent of the General
Partner, the General Partner, subject to Section 8(c), shall promptly
obtain and maintain in full force and effect directors’ and officers’ liability
insurance (“D&O Insurance”) in reasonable amounts from established
and reputable insurers, and the General Partner’s Organizational Documents
shall at all times provide for indemnification and exculpation of officers and
directors to the fullest extent permitted under applicable law.


(b)           Rights and Benefits. In all
policies of D&O Insurance, Indemnitees shall be named as an insured in such
a manner as to provide Indemnitees the same rights and benefits as are accorded
to the most favorably insured of the General Partner’s officers and
directors.  The General Partner shall
advise Indemnitees as to the general terms of, and the amounts of coverage
provide by, any liability insurance policy described in this Section 8 and
shall promptly notify Indemnitees if, at any time, any such insurance policy
will no longer be maintained or the amount of coverage under any such insurance
policy will be decreased.


(c)           Limitation on Required Maintenance
of D&O Insurance. 
Notwithstanding the foregoing, the General Partner shall have no
obligation to obtain or maintain D&O Insurance if the General Partner
determines in good faith that such insurance is not reasonably available, the
premium costs for such insurance are disproportionate to the amount of coverage
provided, the coverage provided by such insurance is limited by exclusions so
as to provide an insufficient benefit, or Indemnitees is covered by similar
insurance maintained by a subsidiary of the General Partner.



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9.             Exceptions.


Any
other provision herein to the contrary notwithstanding, the General Partner
shall not be obligated pursuant to the terms of this Agreement to indemnify
Indemnitees:


(a)           against any Losses or Expenses, or
advance Expenses to Indemnitees, with respect to Claims initiated or brought
voluntarily by Indemnitees, and not by way of defense (including, without
limitation, affirmative defenses and counterclaims), except (i) Claims to
establish or enforce a right to indemnification, contribution or advancement
with respect to an Indemnification Event, whether under this Agreement, any
other agreement or insurance policy, the General Partner’s Organizational
Documents of any Covered Entity, the laws of the State of Delaware or
otherwise, (ii) if MarkWest Energy GP, L.L.C.’s board of directors has approved
specifically the initiation or bringing of such Claim. (iii) if such
indemnification is expressly required to be made by law, or (iv) if such
indemnification is provided by MarkWest Energy GP, L.L.C., in its sole
discretion, pursuant to the powers vested in MarkWest Energy GP, L.L.C. under
the Delaware Limited Liability Company Act;


(b)           against any Losses or Expenses, or
advance Expenses to Indemnitees, with respect to any proceeding instituted by
Indemnitees to enforce or interpret this Agreement, if a court of competent
jurisdiction determines that the material assertions made by Indemnitees in
such proceeding were not made in good faith or were frivolous;


(c)           for any amounts paid in settlement of
a proceeding unless the General Partner consents to such settlement, which
consent shall not be unreasonably withheld;


(d)           against any Losses or Expenses, or
advance Expenses to Indemnitees, with respect to Claims arising (i) with
respect to an accounting of profits made from the purchase and sale (or sale
and purchase) by Indemnitees of securities of the General Partner within the
meaning of Section 16(b) of the Exchange Act or (ii) pursuant to Sections 304
or 306 of the Sarbanes-Oxley Act of 2002, as amended, or any rule or regulation
promulgated pursuant thereto; or


(e)           if, and to the extent, that a court
of competent jurisdiction renders a final, unappealable decision that such indemnification
is not lawful.


10.          Remedies
of Indemnitees.


(a)           Right to Petition Court.  In the event that Indemnitees makes a request
for payment of Losses and Expenses or a request for an advancement of Expenses
and the General Partner fails to make such payment or advancement in a timely
manner pursuant to the terms of this Agreement, Indemnitees may petition a
court of law to enforce the General Partner’s obligations under this Agreement.


(b)           Burden of Proof.  In any judicial proceeding brought under this
Section 10, the General Partner shall have the burden of proving by clear and
convincing evidence that Indemnitees is not entitled to payment of Losses and
Expenses hereunder.


(c)           Expenses.  The General Partner agrees to reimburse
Indemnitees in full for any Expenses incurred by Indemnitees in connection with
investigating, preparing for, litigating, 



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defending or settling any action brought by
Indemnitees under this Section 10, or in connection with any claim or
counterclaim brought by the General Partner in connection therewith.


(d)           Validity of Agreement.  The General Partner shall be precluded from
asserting in any Proceeding, including, without limitation, an action under
this Section 10, that the provisions of this Agreement are not valid, binding
and enforceable or that there is insufficient consideration for this Agreement
and shall stipulate in court that the General Partner is bound by all the
provisions of this Agreement.


(e)           Failure to Act Not a Defense.  The failure of the General Partner (including
its Board of Directors or any committee thereof, Independent Legal Counsel or
stockholders) to make a determination concerning the permissibility of the
payment of Losses and Expenses or the advancement of Expenses under this
Agreement shall not be a defense in any action brought under this Section 10,
and shall not create a presumption that such payment or advancement is not
permissible.


11.          Survival
of Rights.


(a)           All agreements and obligations of the
General Partner contained herein shall continue during the period Indemnitees
is an agent of the General Partner and shall continue thereafter so long as
Indemnitees shall be subject to any possible claim or threatened, pending or
completed action, suit or proceeding, whether civil, criminal, arbitrational,
administrative or investigative, by reason of the fact that Indemnitees was
serving in the capacity referred to herein.


(b)           The General Partner shall require any
successor to the General Partner (whether direct or indirect, by purchase,
merger, consolidation or otherwise) or to all or substantially all of the
business or assets of the General Partner, expressly to assume and agree to
perform this Agreement in the same manner and to the same extent that the
General Partner would be required to perform if no such succession had taken
place.


12.          Miscellaneous.


(a)           Counterparts.  This Agreement may be executed in one or more
counterparts, each of which shall constitute an original.


(b)           Binding Effect; Successors and
Assigns.  This Agreement shall be
binding upon and inure to the benefit of and be enforceable by the parties
hereto and their respective successors and assigns (including with respect to
the General Partner, any direct or indirect successor by purchase, merger,
consolidation or otherwise to all or substantially all of the business and/or
assets of the General Partner) and with respect to Indemnitees, his or her
spouse, heirs, and personal and legal representatives.  The General Partner shall require and cause
any successor or assign (whether direct or indirect, by purchase, merger,
consolidation or otherwise) to all, substantially all, or a substantial part,
of the business and/or assets of the General Partner, to assume and agree to
perform this Agreement in the same manner and to the same extent that the
General Partner would be required to perform if no such succession or
assignment had taken place.  This
Agreement shall continue in effect with respect to Claims relating to
Indemnification Events regardless of whether Indemnitees continues to serve as
a director, officer, employee, controlling person, agent or fiduciary of any
Covered Entity.



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(c)           Notice.  All notices and other communications required
or permitted hereunder shall be in writing, shall be effective when given, and
shall in any event be deemed to be given (i) five (5) days after deposit with
the U.S. Postal Service or other applicable postal service, if delivered by
first class mail, postage prepaid, (ii) upon delivery, if delivered by hand,
(iii) one (1) business day after the business day of deposit with Federal
Express or similar, nationally recognized overnight courier, freight prepaid,
or (iv) one (1) business day after the business day of delivery by confirmed
facsimile transmission, if deliverable by facsimile transmission, with copy by
other means permitted hereunder, and addressed, if to Indemnitees, to
Indemnitees’ address or facsimile number (as applicable) as set forth beneath
Indemnitees’ signature to this Agreement, or, if to the General Partner, at the
address or facsimile number (as applicable) of its principal corporate offices
(attention: Secretary), or at such other address or facsimile number (as
applicable) as such party may designate to the other parties hereto. 


(d)           Enforceability.  This Agreement, when executed and delivered
by the General Partner in accordance with the provisions hereof, shall be a
legal, valid and binding obligation of the General Partner, enforceable against
the General Partner in accordance with its terms.


(e)           Consent to Jurisdiction.  The General Partner and Indemnitees each
hereby irrevocably consent to the jurisdiction and venue of the federal or
state courts located in the State of Delaware for all purposes in connection
with any Proceeding which arises out of or relates to this Agreement and agree
that any Proceeding instituted under this Agreement shall be commenced,
prosecuted and continued only in the federal or state courts located in the
State of Delaware.


(f)            Severability.  The provisions of this Agreement shall be
severable in the event that any of the provisions hereof (including any
provision with a single section, paragraph or sentence) are held by a court of
competent jurisdiction to be invalid, void or otherwise unenforceable, and the
remaining provisions shall remain enforceable to the fullest extent permitted
by law.  Furthermore, to the fullest
extent possible, the provisions of this Agreement (including, without
limitation, each portion of this Agreement containing any provision held to be
invalid, void or otherwise unenforceable that is not itself invalid, void or
unenforceable) shall be construed so as to give effect to the extent manifested
by the provision held invalid, illegal or unenforceable.


(g)           Choice of Law.  This Agreement shall be governed by and its
provisions shall be construed and enforced in accordance with, the laws of the
State of Delaware, without regard to the conflict of laws principles thereof.


(h)           Subrogation.  In the event of payment under this Agreement,
the General Partner shall be subrogated to the extent of such payment to all of
the rights of recovery of Indemnitees (other than with respect to any rights of
recovery under any insurance policy maintained by the Indemnitees or by any
Person (other than the General Partner) for and on behalf of the Indemnitees)
who shall execute all documents required and shall do all acts that may be
necessary to secure such rights and to enable the General Partner effectively
to bring suit to enforce such rights.


(i)            Amendment and Termination.  No amendment, modification, termination or
cancellation of this Agreement shall be effective unless it is in a writing
signed by the parties to be bound thereby. 
Notice of same shall be provided to all parties hereto.  No waiver of any of the provisions of this
Agreement shall be deemed or shall constitute a waiver of any other provisions
hereof (whether or not similar) nor shall such waiver constitute a continuing
waiver.



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(j)            No Construction as Employment
Agreement.  Nothing contained in this
Agreement shall be construed as giving Indemnitees any right to be retained or
continue in the employ or service of any Covered Entity.


IN
WITNESS WHEREOF, the parties hereto have executed this Agreement on and as of
the day and year first above written.


	
   

  	
  MarkWest Energy GP, L.L.C.

  	
   

  	
   

  
	
   

  	
  a Delaware
  limited liability company

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  MarkWest
  Energy Partners, L.P.

  	
   

  	
   

  
	
   

  	
  a Delaware
  limited partnership

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  INDEMNITEES:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  Name:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  Address:

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
								



 



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