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                                                                    Exhibit 10.4

                                                                [Execution Copy]


                         BUSINESS OPPORTUNITY AGREEMENT

         This BUSINESS OPPORTUNITY AGREEMENT, dated as of June 29, 2001 (this
"Agreement"), is among ANKER COAL GROUP, INC., a Delaware corporation (the
"Company"), the Persons (as defined below) who have executed this Agreement as
shareholders of the Company (collectively, the "Shareholders"), the Persons who
have executed this Agreement as holders of the Company's 14.25% Series B Second
Priority Senior Secured Notes due 2001 (collectively, the "Bondholders"),
Wexford Capital LLC, a Connecticut limited liability company ("Wexford"),
Valentis Investors LLC, a Delaware limited liability company ("Valentis"),
Wexford Spectrum Investors LLC, a Delaware limited liability company
("Spectrum"), Solitair Corp., a Delaware Corporation ("Solitair") the Company,
the Shareholders and the Bondholders are sometimes referred to collectively
herein as the "Parties".

                                  INTRODUCTION

         WHEREAS, Wexford serves as the investment manager or the manager of
Valentis, Spectrum and Solitair and one or more employees of Wexford or other
entities for which Wexford serves as investment manager or manager (together
with Valentis, Spectrum and Solitair, the "Wexford Entities") may be elected to
the board of directors of the Company; and

         WHEREAS, the Wexford Entities and their Affiliates own interests in a
number of corporations, partnerships and other entities engaged in coal
production, transportation, distribution, and consumption and other
energy-related businesses and intend to acquire from time to time additional
interests in such Persons (as defined below) or in other Persons engaged in such
activities;

         WHEREAS, Wexford Entities may owe fiduciary or contractual duties to
other Wexford Entities and to other Persons;

         WHEREAS, in the absence of this Agreement there could arise
circumstances in which a Wexford Entity may be alleged to have duties to offer a
Business Opportunity (as defined below) to the Company by virtue of the fact
that an employee of the Wexford Entity or of an Affiliate thereof serves on the
board of directors of the Company;

         WHEREAS, Wexford is unwilling to permit its employees or employees of
other Wexford Entities to serve on the Company's board of directors in the
absence of an agreement that will permit Wexford Entities and their Affiliates
to conduct their businesses as now conducted and as contemplated;


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         WHEREAS, each of the Wexford Entities has relied on the fact that this
Agreement would be executed and in the future will rely on this Agreement and
the commitments herein made by the Company, the Shareholders and the
Bondholders; Wexford, Valentis, Spectrum, Solitair and other Wexford Entities
that are beneficiaries of this Agreement will rely on this Agreement and the
commitments herein made by the Company, the Shareholders and the Bondholders;

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

         1. Definitions. The following terms shall have the following meanings:

         "Affiliate" of a Person means any Person controlling, controlled by, or
under common control with such Person, with "control" and its correlative terms
meaning the possession, directly or indirectly, of the power to direct or cause
the direction of management or policies (whether through ownership of securities
or any partnership or other ownership interest, by contract or otherwise) of a
Person. For the purpose of this Agreement, "control" shall also include serving
as a manager or general partner of a Person or performing similar functions for
a Person. Solely for the purposes of this definition, "control" shall include
the possession, directly or indirectly, through one or more intermediaries, of
(A) in the case of a corporation, 50% or more of the outstanding securities
thereof; (B) in the case of a limited liability company, partnership, limited
partnership or venture, the right to 50% or more of the distributions therefrom
(including liquidating distributions); and (C) in the case of any other Person,
50% or more of the economic or beneficial interest therein; provided, however,
in the case of all references in this Agreement to Affiliates of Wexford or
Wexford Entities, each of the references to "50%" in this sentence shall instead
be to "10%".

         "Business Opportunity" means any opportunity for a Person (a) to enter
into any transaction pursuant to which such Person would acquire (whether by
purchase, lease, or other transaction), own, invest in, finance, lend funds to,
contribute capital to, manage, operate, or otherwise participate in (or with)
any Person, assets or other transaction, (b) to market, broker, purchase, sell
or trade in bituminous coal, coke or other coal by-products (including, coal,
coke or other coal by-products produced by the Company), (c) to produce, process
or consume bituminous coal, coke or other coal by-products or to operate coal
mines or coal processing facilities of any kind, (d) to generate electricity
using bituminous coal or coal by-products, or (e) to act as a broker, finder,
financial advisor or investment banker with respect to any of the foregoing
activities by any other Person.

         "Company" means the Company, acting for itself and on behalf of its
Affiliates in which the Company owns an interest, directly or indirectly, unless
the context otherwise requires.

         "Person" means any natural person, corporation, limited partnership,
limited liability company, general partnership, joint stock company, joint
venture, association, company, trust, bank, trust company, land trust, business
trust or other organization, whether or not a legal entity.

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         2. Renunciation of Business Opportunities. (a) To the fullest extent
permitted by law, the Company hereby renounces any interest or expectancy in any
Business Opportunity developed by a Wexford Entity, and the Company, the
Shareholders and the Bondholders agree that no Wexford Entity has any obligation
to offer any such Business Opportunity to the Company. Except as provided in
clause (c) below and without waiving any right to claim a breach of any other
provision of this Agreement, to the fullest extent permitted by law, the
Company, the Shareholders and the Bondholders further agree that no employee of
any Wexford Entity who serves as a member of the Company's board of directors
(collectively, the "Designated Directors") shall be expressly or implicitly
restricted or proscribed by virtue of this Agreement, the relationship that
exists between the Wexford Entities or the Designated Directors (or any of them)
and the Company or otherwise, from engaging in any type of business activity
(including in a Business Opportunity) or owning an interest in any type of
business entity, regardless of whether such business activity is (or such
business entity engages in businesses that are) in direct or indirect
competition with the business of the Company or any of its Affiliates. Without
limiting the foregoing and to the fullest extent permitted by law, by virtue of
the renunciations of Business Opportunities herein, the Shareholders, the
Bondholders and the Company agree that (1) neither the Company nor any of its
Affiliates nor any other Person shall have any rights, by virtue of this
Agreement, the relationship that exists between the Wexford Entities or the
Designated Directors (or any of them) and the Company or otherwise, in any
business venture or business opportunity of any Wexford Entity or any of their
respective Affiliates, and none of the Wexford Entities or their respective
Affiliates or designees or the Designated Directors shall have any obligation to
offer any interest in any such business venture or business opportunity
(including any Business Opportunity) to the Company or any of its Affiliates or
any other Person, or otherwise account to any of such Persons in respect of any
such business ventures or opportunities, and (2) it shall not be deemed a breach
of any fiduciary or other duties, if any, whether express or implied, for any
Wexford Entity to permit itself or one of its Affiliates or designees to engage
in a business opportunity (including, a Business Opportunity) in preference or
to the exclusion of the Company or any of its Affiliates or any other Person.

         (b) Specifically and without limiting the generality of the foregoing,
an employee of a Wexford Entity who serves on the board of directors of the
Company may, in the course of his or her employment with a Wexford Entity,
encounter business opportunities that the Company or any of its Affiliates may
desire to pursue. The Company and its Shareholders recognize that such
opportunities may include the Business Opportunities renounced above.

         (c) Notwithstanding anything to the contrary herein, the Company does
not renounce any interest or expectancy in a Business Opportunity that is
presented to a director of the Company solely in, and as a direct result of, his
or her capacity as a director of the Company, unless such opportunity is
separately presented to any Wexford Entity or its Affiliates (including a
separate presentation to a Wexford Entity or its Affiliates through a Designated
Director in his or her capacity as an employee of a Wexford Entity or its
Affiliates), in which case such entity shall be free to pursue such opportunity.

         3. Transactions with the Company. The Company may enter into one or
more agreements with a Wexford Entity to render services to the Company, provide
funds or credit support to the Company or sell, transfer or convey property or
assets to, and from, the

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Company. Any such transaction will only be performed by a Wexford Entity after
such transaction is approved by the Company's board of directors (excluding any
director who is an employee of a Wexford).

         4. Waivers Included in the Company's Organizational Documents. The
Company and the Shareholders hereby agree that the renunciations, waivers and
other provisions of Section 2 above will be added to the Company's
organizational documents in form and substance acceptable to Wexford.

         5. Indemnification. (a) The Company agrees to defend, indemnify and
hold harmless each Wexford Entity, and its shareholders, managers, directors,
officers, employees (including the Designated Directors), agents, Affiliates,
successors and assigns, and each of them (collectively, the "Indemnified
Parties"), of and from any and all debts, obligations, liabilities, deficiency,
damages, claims, demands, actions, orders, causes of action, proceedings, fines,
penalties, taxes, costs and expenses (including without limitation, attorneys
and accountants fees) of any kind and nature (collectively, "Damages"), that may
be suffered or incurred by them, or any of them, resulting from or arising out
of the non-fulfillment of any covenant, agreement, waiver, renunciation or
obligation of the Company contained in this Agreement. Without limiting the
foregoing, each Indemnified Party who was or is made a party or is threatened to
be made a party to or is involved in any action, suit or proceeding, whether
civil, criminal, administrative or investigative (hereinafter a "proceeding"),
by reason of the fact that an employee of a Wexford Entity is or was a director
of the Company or is or was serving at the request of the Company as a director,
whether the basis of such proceeding is alleged action in an official capacity
as a director, or in any other capacity while serving as a director, shall be
indemnified and held harmless by the Company to the fullest extent authorized by
the Delaware General Corporation Law, as the same exists or may hereafter be
amended (but, in the case of any such amendment, only to the extent that such
amendment permits the corporation to provide broader indemnification rights than
said law permitted the Company to provide prior to such amendment), against all
Damages reasonably incurred or suffered by such Person in connection therewith
and such indemnification shall continue as to a Person who has ceased to be a
director of the Company and shall inure to the benefit of its, his or her heirs,
executors, administrators, successors and assigns. The right to indemnification
conferred in this Section shall be a contract right and shall include the right
to be paid by the Company the expenses incurred in defending any such proceeding
in advance of its final disposition; provided, however, that, if the Delaware
General Corporation Law requires, the payment of such expenses incurred by a
director or officer in his or her capacity as a director or officer (and not in
any other capacity in which service was or is rendered by such person while a
director or officer) in advance of the final disposition of a proceeding, shall
be made only upon delivery to the Company of an undertaking, by or on behalf of
such director or officer, to repay all amounts so advanced if it shall
ultimately be determined that such director or officer is not entitled to be
indemnified under this Section or otherwise.

         (b) If a claim under this Section 5 is not paid in full by the Company
within thirty days after a written claim has been received by the Company, the
claimant may at any time thereafter bring suit against the Company to recover
the unpaid amount of the claim and, if the claimant substantially prevails, the
claimant shall be entitled to be paid also the reasonable expense incurred in
prosecuting such claim. It shall be a defense to any such action (other than

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an action brought to enforce a claim for expenses incurred in defending any
proceeding in advance of its final disposition where the required undertaking,
if any is required, has been tendered to the Company) that the claimant has not
met the standards of conduct which make it permissible under the Delaware
General Corporation Law for the corporation to indemnify the claimant for the
amount claimed, but the burden of proving such defense shall be on the Company.
Neither the failure of the Company (including its Board of Directors,
independent legal counsel, or its stockholders) to have made a determination
prior to the commencement of such action that indemnification of the claimant is
proper in the circumstances because he or she has met the applicable standard of
conduct set forth in the Delaware General Corporation Law, nor an actual
determination by the Company (including its Board of Directors, independent
legal counsel, or its stockholders) that the claimant has not met such
applicable standard of conduct, shall be a defense to the action or create a
presumption that the claimant has not met the applicable standard of conduct.

         (c) Notwithstanding anything herein to the contrary, if an Indemnified
Party determines in good faith that there is a reasonable probability that a
proceeding may adversely affect it or its Affiliates, the Indemnified Party may
assume the exclusive right to defend, compromise, or settle such proceeding, but
the Company will not be bound by any determination of a proceeding so defended
or any compromise or settlement effected without its consent (which may not be
unreasonably withheld or delayed). If, within 30 days of the Company's receipt
of a notice from an Indemnified Party of a claim under this Section, the Company
shall not have notified the Indemnified Party of its desire to assume the
defense of such proceeding, the Indemnified Party shall also have the right to
assume control of the defense or compromise of such proceeding, and the
Indemnified Party shall have the right to settle or compromise such proceeding
without the consent of the Company.

         (d) The right to indemnification and the payment of expenses incurred
in defending a proceeding in advance of its final disposition conferred in this
Section shall not be exclusive of any other right which any person may have or
hereafter acquire under any statute, provision of the Certificate of
Incorporation, bylaw, agreement, vote of stockholders or disinterested directors
or otherwise.

         6. Insurance. The Company shall use commercially reasonable efforts to
maintain, at its expense, a directors and officers' insurance policy
substantially similar to its existing policy and reasonably acceptable to
Wexford.

         7. Remedies, Arbitration and Governing Law. (a) With the exception of
the injunctive relief under Section 8 hereof, the Parties hereto agree that all
claims, counterclaims, demands, cause of action, disputes, controversies, and
other matters in question arising out of or relating to this Agreement or any
provision hereof, the alleged breach of any such provision, or in any way
relating to the subject matter hereof, or the relationship between the Parties
created by this Agreement or the relationship existing between the Wexford
Entities and the Designated Directors (or any of them) and the Company (all of
which are referred to herein as "Disputed Claims"), even though some or all of
such disputed claims allegedly are extra-contractual in nature, whether such
disputed claims sound in contract, tort, or otherwise, at law or in equity,
under state or federal law, whether provided by statute or the common law, for
damages or any other relief, shall be resolved by binding arbitration pursuant
to the Federal Arbitration Act.


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         (b) The validity, construction, and interpretation of this agreement to
arbitrate, and all procedural aspects of the arbitration conducted pursuant to
this Agreement to arbitrate, including but not limited to, the determination of
the issues that are subject to arbitration (i.e., arbitrability), the scope of
the arbitrable issues, allegations of "fraud in the inducement" to enter into
this agreement or this arbitration provision, allegations of waiver, laches,
delay or other defenses to arbitrability, and the rules governing the conduct of
the arbitration (including the time for filing an answer, the time for the
filing of counter disputed claims, the times for amending the pleadings, the
specificity of the pleadings, the extent and scope of discovery, the issuance of
subpoenas, the times for the designation of experts, whether the arbitration is
to be stayed pending resolution of related litigation involving third parties
not bound by this Agreement, the receipt of evidence, and the like), shall be
decided by the arbitrators. In deciding the substance of any Party's Disputed
Claims, the arbitrators shall refer to the substantive laws of the State of
Delaware for guidance (excluding Delaware choice-of-law principles that might
call for the application of some other state's law).

         (c) NOTWITHSTANDING ANY OTHER PROVISION IN THIS ARBITRATION AGREEMENT
TO THE CONTRARY, THE PARTIES EXPRESSLY AGREE THAT THE ARBITRATORS SHALL HAVE
ABSOLUTELY NO AUTHORITY TO AWARD TREBLE, EXEMPLARY OR PUNITIVE DAMAGES OF ANY
TYPE UNDER ANY CIRCUMSTANCES REGARDLESS OF WHETHER SUCH DAMAGES MAY BE AVAILABLE
UNDER DELAWARE LAW, THE LAW OF ANY OTHER STATE, OR FEDERAL LAW, OR UNDER THE
FEDERAL ARBITRATION ACT, OR UNDER THE AMERICAN ARBITRATION ASSOCIATION RULES IN
EFFECT AS OF THE DATE OF THIS AGREEMENT, THE PARTIES HEREBY WAIVING THEIR RIGHT,
IF ANY, TO RECOVER TREBLE, EXEMPLARY OR PUNITIVE DAMAGES IN CONNECTION WITH ANY
SUCH DISPUTED CLAIMS.

         (d) The arbitration proceedings shall be conducted in Wilmington,
Delaware by three arbitrators. The arbitration proceeding will be conducted in
accordance with, and subject to, the procedures established for commercial
arbitrations by the American Arbitration Association, but shall not be conducted
using or with any direct involvement by that association (except as otherwise
provided below). Within 30 days of the notice of initiation of the arbitration
procedure, an affected Party shall select one arbitrator by notice to any other
affected Parties and the two arbitrators so selected by the affected Parties
shall select a third arbitrator. Absent such agreement by the two arbitrators,
the third arbitrator shall be selected by the American Arbitration Association
upon the joint petition by the affected Parties. The arbitration shall be
governed by the United States Arbitration Act, 9 U.S.C. ss. 1-16, as such act is
modified by this Agreement, and judgment upon the award rendered by the
arbitrators may be entered by any court having jurisdiction thereof.

         (e) All fees of the arbitrators and other administrative charges
related to the arbitration shall be borne equally by the Parties.

         (f) The award of the arbitrators shall be final and binding on the
Parties and judgment thereon may be entered in a court of competent
jurisdiction.



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         (g) The Parties hereby (i) irrevocably and unconditionally waive, to
the fullest extent permitted by law, trial by jury in any legal action or
proceeding relating to this Agreement and for any counterclaim therein; (ii)
irrevocably waive, to the maximum extent not prohibited by law, any right it may
have to claim or recover in any arbitration or litigation any special,
exemplary, punitive or consequential damages, or damages other than, or in
addition to, actual damages, interest, fees and costs; (iii) certify that no
Party hereto nor any representative or agent or counsel for any Party hereto has
represented, expressly or otherwise, or implied that such Party would not, in
the event of arbitration or litigation, seek to enforce the foregoing waivers,
and (iv) acknowledge that the Parties have been induced to enter into this
agreement by, among other things, the waivers and certifications contained in
this Section.

         8. Confidentiality. (a) Each of the Company and Wexford shall hold, and
shall cause each Person controlled by it to hold, in confidence any information
exchanged between the Company and any Designated Directors received solely in,
and as a direct result of, the duties performed by any Designated Directors as
members of the Company's board of directors (collectively, the "Confidential
Information"), and except as otherwise provided in this Section, neither the
Company nor Wexford will use, or permit any Person controlled by it to use, the
Confidential Information other than for the purpose of performing any
obligations hereunder or, in the case of the Designated Directors, in the
performance of their duties as members of the Company's board of directors;
provided however, that such restrictions with respect to such Confidential
Information shall not apply to, and the term Confidential Information shall not
include, (i) information that is or becomes generally available to the public,
(ii) disclosures required to be made by applicable laws and regulations
(including, without limitation, disclosures required by any order, subpoena or
other legal process); (iii) disclosures to (x) actual or potential investors,
lenders or other capital providers to such party, (y) officers, directors,
employees, agents or representatives of such party and of Persons controlled by
such party or (z) auditors, counsel and other professional advisors to such
party (provided, however, that such Persons described in (x), (y) and (z) above
have been informed of the confidential nature of the information, and, in any
event, the disclosing party shall be responsible for any failure by such Person
to abide by the provisions of this Section 8), (iv) disclosures in connection
with any litigation or dispute between or with the Parties, the Designated
Directors, or any representatives thereof, (v) information known to the
receiving party at the time of disclosure or is thereafter acquired at any time
from a source other than the other party hereto that was not known to the
receiving party to be prohibited from making disclosure or (vi) information that
is hereafter independently developed by the receiving party.

         (b) As noted above, the Company may enter into one or more agreements
with a Wexford Entity to render services to the Company, provide funds or credit
support to the Company or sell, transfer or convey property or assets to, and
from, the Company, and nothing herein shall prevent such Wexford Entity from
using any such Confidential Information for the purpose of evaluating,
negotiating and/or consummating any proposed transaction with the Company.
Furthermore, notwithstanding anything to the contrary in this Agreement or this
Section 8, the Company, the Shareholders and the Bondholders understand and
agree that certain activities of each Wexford Entity or any of their respective
Affiliates may now, or in the future, be in direct or indirect competition with
the activities of the Company and/or any of its Affiliates and, in such event,
Wexford shall implement certain firewall procedures with respect to such
proposed activities in order to prevent employees of a Wexford Entity or any of
its Affiliates that

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<PAGE>   8

will be involved in a particular transaction from obtaining from Wexford or a
Designated Director confidential information relating to such competitive
transaction, including any proposed bid amount applicable to a particular
competitive transaction, that might constitute Confidential Information under
this Agreement. If a Designated Director is directly involved in such
competitive transaction on behalf of a Wexford Entity or any Affiliate thereof
and the Company is also seeking approval from the Company's board of directors
to participate in such competitive transaction, then the Designated Director
will recuse himself or herself from the Company's board of director
deliberations relating to such transaction, but may continue his or her
involvement in such transaction on behalf of such Wexford Entity or Affiliate.

         (c) Each party hereto shall have the right to apply to a court to
enjoin any breach of this Section 8. Excepting the right of a party to seek such
injunctive relief, all claims and matters in question arising out of this
Section, whether sounding in contract, tort or otherwise, shall be resolved by
binding arbitration as set forth in Section 7 hereof.

         (d) To the fullest extent permitted by law, the Company, the
Shareholders and the Bondholders agree that, to the extent that a court might
hold that the conduct of any activity permitted by this Section 8 may constitute
a breach by a Designated Director of his or her duty of confidentiality or duty
to restrict the use of Confidential Information to the Company or any of its
Affiliates, or to any other Person, the Company, the Shareholders and the
Bondholders hereby waive and renounce any and all claims and causes of action
that the Company or any of its Affiliates, the Shareholders, the Bondholders or
any other Person may have as a consequence of such conduct or activities.

         9. Resignation of Designated Directors. Notwithstanding anything in the
Company's articles of incorporation, its bylaws or other organization documents
to the contrary, the Company, the Shareholders and the Bondholders acknowledge
and agree that any Designated Director on the Company's board of directors may
resign at any time and such resignation shall be effective immediately upon
delivery of a notice thereof to the Company by such director in accordance with
the notice provisions hereof.

         10. Miscellaneous.

         (a) Section titles or captions in this Agreement are included for
purposes of convenience only and shall not be considered a part of this
Agreement in construing or interpreting any of its or their provisions. All
references in this Agreement to Sections shall refer to Sections of this
Agreement unless the context clearly otherwise requires.

         (b) When used in this Agreement, the word "including" shall have its
normal common meaning and any list of items that may follow such word shall not
be deemed to represent a complete list of the contents of the referent of the
subject.

         (c) The Parties have participated jointly in the negotiation and
drafting of this Agreement. If any ambiguity or question of intent or
interpretation arises, no presumption or burden of proof shall arise favoring or
disfavoring any party by virtue of the authorship of any of the provisions of
this Agreement or such other documents.

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<PAGE>   9

         (d) Unless the context otherwise requires, when used in this Agreement,
the singular shall include the plural, the plural shall include the singular,
and all nouns, pronouns and any variations thereof shall be deemed to refer to
the masculine, feminine or neuter, as the identity of the person or persons may
require.

         (e) This Agreement may be executed in several counterparts, each of
which is an original and all of which, when taken together, constitute one and
the same instrument.

         (f) This Agreement embodies the entire agreement and understanding of
the Parties related to its subject matter and supersede all prior proposals,
understandings, agreements, correspondence, arrangements and contemporaneous
oral agreements relating to such subject matter. No representation, promise,
inducement or statement of intention has been made by any Party which has not
been embodied in this Agreement. This Agreement may be modified only by a
written instrument signed by the Parties hereto. Any original executed agreement
or document may be photocopied and stored on computer tapes and disks (the
"Imaged Agreement"). The Imaged Agreement, if introduced as evidence on paper,
and the transaction tape, if introduced as evidence in its original form and as
transcribed onto paper, and all computer records of the foregoing, if introduced
as evidence in printed format, in any judicial, arbitration, mediation or
administrative proceedings, will be admissible as among the relevant Parties to
the same extent and under the same conditions as other business records
originated and maintained in documentary form. No relevant Party shall object to
the admissibility of the transaction tape or the Imaged Agreement (or
photocopies of the transcription of the transaction tape or the Imaged
Agreement) on the basis that such were not originated or maintained in
documentary form under either the hearsay rule, the best evidence rule or other
rule of evidence.

         (g) Each Party will bear its own expenses incurred in connection with
the preparation, execution and performance of its obligations under this
Agreement including all fees and expenses of agents, representatives, counsel
and accountants.

         (h) This Agreement shall only be enforceable by the Parties hereto,
their respective successors, permitted assigns, heirs, executors, administrators
and personal representatives, and is also intended for the benefit of, and is
enforceable by, each of the Designated Directors and each Wexford Entity and
their respective heirs, administrators, executors, successors and assigns.
Except as contemplated in the preceding sentence, this Agreement is not intended
to, nor shall it be construed to, confer upon any other third person any right,
remedy or benefit, nor are they intended to be enforceable by any other third
person.

         (i) All notices, requests, statements or payments required or permitted
to be made or given under this Agreement shall be delivered to the addresses set
forth below, and made as specified below. Notices required to be in writing
shall be delivered by letter, facsimile or other documentary form. Notice by
facsimile or hand delivery shall be deemed to have been received by the close of
the business day on which it was transmitted or hand delivered (unless
transmitted or hand delivered after the close of the business day, in which case
it shall be deemed received at the close of the next business day). Notice by
overnight mail or courier shall be deemed to have been received two business
days after it was sent. A Party may change its address by providing notice of
same in accordance herewith.

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If one or more Wexford Entities         C/o Wexford Capital LLC
                                        411 West Putnam Avenue
                                        Greenwich, CT  06830
                                        Attention: Arthur Amron and Mark Zand
                                        Facsimile:   (203) 862-7312
                                        Telephone:   (203) 862-7012

If to the Company:                      Anker Coal Group, Inc.
                                        2708 Cranberry Square
                                        Morgantown, WV 26508
                                        Attention:  President
                                        Facsimile:   (304) 594-1685
                                        Telephone:   (304) 594-1616


If to the Shareholders:                 To their respective addresses and
                                        facsimile numbers set forth opposite
                                        their signatures to this Agreement.

If to Bondholders:                      To their respective addresses and
                                        facsimile numbers set forth opposite
                                        their signatures to this Agreement.

         (j) If a court or arbitrator in any final, unappealable proceeding
holds any provision of this Agreement or its application to any person or
circumstance, invalid, illegal or unenforceable, the remainder of this
Agreement, or the application of such provision to persons or circumstances
other than those to which it was held to be invalid, illegal or unenforceable,
shall not be affected, and shall be valid, legal and enforceable to the fullest
extent permitted by law, but only if and to the extent such enforcement would
not materially and adversely frustrate the Parties' essential objectives as
expressed in this Agreement taken as a whole. Furthermore, in lieu of any such
invalid or unenforceable term or provision, the Parties intend that the court or
arbitrator add to this Agreement a provision as similar in terms to such invalid
or unenforceable provision as may be valid and enforceable, so as to effect the
original intent of the Parties to the greatest extent possible.

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<PAGE>   11



         EXECUTED as of the date first above written.


                                        ANKER COAL GROUP, INC.

                                        By: /s/ Bruce Sparks
                                            ------------------------------------

                                        Name: Bruce Sparks
                                              ----------------------------------

                                        Title: President
                                               ---------------------------------


                                        WEXFORD CAPITAL LLC

                                        By: /s/ Mark Zand
                                            ------------------------------------

                                        Name: Mark Zand
                                              ----------------------------------

                                        Title: Senior Vice President
                                               ---------------------------------


                                        VALENTIS INVESTOR LLC

                                          BY: ITS MANAGER:
                                              WEXFORD CAPITAL LLC

                                        By: /s/ Mark Zand
                                            ------------------------------------

                                        Name: Mark Zand
                                              ----------------------------------

                                        Title: Senior Vice President
                                               ---------------------------------


                                        WEXFORD SPECTRUM INVESTORS LLC

                                          BY: ITS MANAGER:
                                              WEXFORD CAPITAL LLC

                                        By: /s/ Mark Zand
                                            ------------------------------------

                                        Name: Mark Zand
                                              ----------------------------------

                                        Title: Senior Vice President
                                               ---------------------------------


                                      -11-
<PAGE>   12



                                        SOLITAIR CORP.

                                        By: /s/ Kenneth H. Rubin
                                            ------------------------------------

                                        Name: Kenneth H. Rubin
                                              ----------------------------------

                                        Title: Vice President
                                               ---------------------------------

                                      -12-
<PAGE>   13




Enron North America Corp.               BONDHOLDERS:
1400 Smith Street
Houston, TX 77002                       ENRON NORTH AMERICA CORP.
Attention:  Donna Lowry, Compliance
Facsimile:  (713) 646-4039              By: ____________________________________
Telephone:  (713) 853-1939
                                        Name: __________________________________
      with a copy to:
                                        Title: _________________________________
Legal Department
Enron North America Corp.
P. O. Box 1188
Houston, TX 77251-1188
Attention:  Managing Director and
General Counsel
Facsimile:   (713) 646-3490


Putnam Investment Management            PUTNAM INVESTMENT MANAGEMENT
1 Post Office Square
Boston, MA 02109
Attention:  Patrick Flynn               By: ____________________________________
Facsimile:   (617) 760-8639
Telephone:   (617) 760-7073             Name: __________________________________

                                        Title: _________________________________


Stonehill Partners                      STONEHILL PARTNERS
126 E. 56th Street - 9th floor
New York, NY 10022
Attention:  Wayne Teetsel               By: ____________________________________
Facsimile:   (212) 838-2336
Telephone:   (212) 739-7474             Name: __________________________________

                                        Title: _________________________________


WL Ross & Co. LLC                       WL ROSS & CO. LLC
101 East 52nd Street, 19th Floor
New York, NY 10022
Attention:  Wilbur Ross                 By: ____________________________________
Facsimile:   (212) 317-4891
Telephone:   (212) 826-2111             Name: __________________________________

                                        Title: _________________________________


                                      -13-
<PAGE>   14



                                        STOCKHOLDERS:

Enron North America Corp.               ENRON NORTH AMERICA CORP.
1400 Smith Street
Houston, TX 77002                       By: ____________________________________
Attention:  Donna Lowry, Compliance
Facsimile:  (713) 646-4039              Name: __________________________________
Telephone:  (713) 853-1939
       With a copy to:                  Title: _________________________________
Legal Department
Enron North America Corp.
P. O. Box 1188
Houston, TX 77251-1188
Attention:  Managing Director and
            General Counsel
Facsimile:  (713) 646-3490


Putnam Investment Management            PUTNAM INVESTMENT MANAGEMENT
1 Post Office Square
Boston, MA 02109
Attention:  Patrick Flynn               By: ____________________________________
Facsimile:  (617) 760-8639
Telephone:  (617) 760-7073              Name: __________________________________

                                        Title: _________________________________


Stonehill Partners                      STONEHILL PARTNERS
126 E. 56th Street - 9th floor
New York, NY 10022
Attention:  Wayne Teetsel               By: ____________________________________
Facsimile:   (212) 838-2336
Telephone:   (212) 739-7474             Name: __________________________________

                                        Title: _________________________________


WL Ross & Co. LLC                       WL ROSS & CO. LLC
101 East 52nd Street, 19th Floor
New York, NY 10022
Attention:  Wilbur Ross                 By: ____________________________________
Facsimile:   (212) 317-4891
Telephone:   (212) 826-2111             Name: __________________________________

                                        Title: _________________________________

                                      -14-