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                                                                   EXHIBIT 10.24

                       SECOND AMENDMENT TO LOAN AGREEMENT

         THIS SECOND AMENDMENT TO LOAN AGREEMENT (this "Amendment") is made and
entered into as of this 7th day of February, 2003, by and among THE CIT
GROUP/BUSINESS CREDIT, INC., a New York corporation (hereinafter "CITBC"), in
its individual capacity as a Lender and as Agent for the Lenders hereinafter
named (hereinafter the "AGENT"), Foothill Capital Corporation, a California
corporation ("FCC"), and any other party hereafter becoming a Lender pursuant to
Section 12.4(b) of the Loan Agreement (as hereinafter defined), each
individually sometimes referred to as a "LENDER" and, collectively, the
"LENDERS"), GREY WOLF DRILLING COMPANY L.P., a Texas limited partnership (the
"BORROWER"), GREY WOLF, INC., a Texas corporation (the "PARENT"), GREY WOLF
HOLDINGS COMPANY, a Nevada corporation ("HOLDINGS"), GREY WOLF LLC, a Louisiana
limited liability company ("GWLLC"), DI ENERGY, INC., a Texas corporation
("ENERGY"), GREY WOLF INTERNATIONAL, INC., a Texas corporation
("INTERNATIONAL"), DI/PERFENSA, INC., a Texas corporation ("PERFENSA"), MURCO
DRILLING CORP., a Delaware corporation ("MURCO") (Parent, Holdings, GWLLC,
Energy, International, Perfensa and Murco are referred to collectively herein as
the "GUARANTORS").

                                    RECITALS

         A.       WHEREAS, pursuant to the terms and subject to the conditions
of that certain Loan Agreement dated as of January 14, 1999 between the parties
hereto, as amended by that certain First Amendment to Loan Agreement dated
December 20, 2001 (such Loan Agreement, as the same was previously amended, is
hereby amended and may hereafter be amended from time to time, being hereinafter
referred to as the "Loan Agreement"), the Borrower was granted a $50,000,000
revolving line of credit which included a letter of credit facility;

         B.       WHEREAS, the indebtedness of the Borrower to the Lenders is
currently evidenced by that certain Revolving Note dated December 20, 2001 (the
"Revolving Note"), executed by the Borrower and payable to CITBC as Agent for
the benefit of the Lenders in the stated principal amount of $75,000,000;

         C.       WHEREAS, payment of the Obligations of the Borrower are
supported by the guarantees of the Guarantors contained in Section 13 of the
Loan Agreement;

         D.       WHEREAS, to secure, in part, the indebtedness under the Loan
Agreement and the Revolving Note (and all renewals, extensions, modifications
and/or rearrangements thereof and in connection therewith) and all other
indebtedness, liabilities and obligations of the Borrower and the Guarantors to
the Agent for the benefit of the Lenders, then existing or thereafter arising,
(i) the Borrower and the Guarantors have heretofore executed in favor of the
Agent certain Credit Documents (as defined in the Loan Agreement), including,
without limitation, the Security Documents (as defined in the Loan Agreement),
which Credit Documents shall continue as amended in connection herewith in full
force and effect upon the execution of this Amendment, all of the Credit
Documents to continue to secure the payment by the Borrower

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and the Guarantors of the Obligations (as defined in the Loan Agreement) all as
more fully set forth therein and herein;

         E.       WHEREAS, the Borrower has requested and, pursuant to the terms
and subject to the conditions hereof and in connection herewith, the Agent and
the Lenders have agreed to increase the Letter of Credit Sublimit (as defined in
the Loan Agreement) to $20,000,000;

         F.       WHEREAS, in furtherance of the foregoing and to evidence the
agreements of the parties hereto in relation thereto the parties hereto desire
to amend the Loan Agreement as hereinafter provided;

         NOW, THEREFORE, in consideration of the premises herein contained and
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the Borrower, the Guarantors, the Agent and the Lenders,
intending to be legally bound, agree as follows:

                                    AGREEMENT

                                    ARTICLE I
                                   DEFINITIONS

         1.01     Capitalized terms used in this Amendment are defined in the
Loan Agreement, as amended hereby, unless otherwise stated.

                                   ARTICLE II
                          AMENDMENTS TO LOAN AGREEMENT

         Effective as of the respective date herein indicated, the Loan
Agreement is hereby amended as follows:

         2.01     AMENDMENT AND RESTATEMENT OF DEFINITION OF "LETTER OF CREDIT
SUBLIMIT". Effective as of the date of execution of this Amendment, the
definition of "Letter of Credit Sublimit" set forth in Section 10 of the Loan
Agreement is amended and restated to read in its entirety as follows:

                  " 'Letter of Credit Sublimit' shall mean $20,000,000."

                                  ARTICLE III
                              CONDITIONS PRECEDENT

         3.01     CONDITIONS TO EFFECTIVENESS. The effectiveness of this
Amendment is subject to the satisfaction of the following conditions precedent
in a manner satisfactory to Agent, unless specifically waived in writing by
Agent:

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                  (a)      Agent shall have received each of the following, each
         in form and substance satisfactory to Agent, in its sole discretion,
         and, where applicable, each duly executed by each party thereto, other
         than Agent:

                           (i)      This Amendment, duly executed by the
                  Borrower and the Guarantors; and

                           (ii)     All other documents Agent may request with
                  respect to any matter relevant to this Amendment or the
                  transactions contemplated hereby.

                  (b)      The representations and warranties contained herein
         and in the Loan Agreement and the other Credit Documents (as defined in
         the Loan Agreement), as each is amended hereby, shall be true and
         correct as of the date hereof, as if made on the date hereof.

                  (c)      No Default or Event of Default shall have occurred
         and be continuing, unless such Default or Event of Default has been
         otherwise specifically waived in writing by Agent.

                  (d)      All corporate proceedings taken in connection with
         the transactions contemplated by this Amendment and all documents,
         instruments and other legal matters incident thereto shall be
         satisfactory to Agent.

                                   ARTICLE IV
                  RATIFICATIONS, REPRESENTATIONS AND WARRANTIES

         4.01     RATIFICATIONS. The terms and provisions set forth in this
Amendment shall modify and supersede all inconsistent terms and provisions set
forth in the Loan Agreement and the other Credit Documents, and, except as
expressly modified and superseded by this Amendment, the terms and provisions of
the Loan Agreement and the other Credit Documents are ratified and confirmed and
shall continue in full force and effect. The Borrower, Agent and Lenders agree
that the Loan Agreement and the other Credit Documents, as amended hereby, shall
continue to be legal, valid, binding and enforceable in accordance with their
respective terms.

         4.02     REPRESENTATIONS AND WARRANTIES. The Borrower and Guarantor
(the "Credit Parties") hereby represent and warrant to Agent and the Lenders
that (a) the execution, delivery and performance of this Amendment and any and
all other Credit Documents executed and/or delivered in connection herewith have
been authorized by all requisite corporate action on the part of the Credit
Parties and will not violate the organizational documents of the Credit Parties;
(b) the Managers or Board of Directors of each of the Credit Parties (or the
Board of Directors of the corporate general partners of any Credit Party that is
a limited partnership) has authorized the execution, delivery and performance of
this Amendment and any and all other Credit Documents executed and/or delivered
in connection herewith; (c) the representations and warranties contained in the
Loan Agreement, as amended hereby, and any other Credit Document are true

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and correct on and as of the date hereof and on and as of the date of execution
hereof as though made on and as of each such date; (d) no Default or Event of
Default under the Loan Agreement, as amended hereby, has occurred and is
continuing, unless such Default or Event of Default has been specifically waived
in writing by Agent; (e) the Credit Parties are in full compliance with all
covenants and agreements contained in the Loan Agreement and the other Credit
Documents, as amended hereby; and (f) the Credit Parties have not amended their
(i) Articles (or Certificates) of Incorporation or their Bylaws, if a
corporation, (ii) limited partnership agreement or certificate of limited
partnership, if a limited partnership, since the date of the Loan Agreement, or
(iii) Articles of Organization or operating agreement, if a limited liability
company, except as otherwise disclosed to Agent.

                                   ARTICLE V
                            MISCELLANEOUS PROVISIONS

         5.01     SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All
representations and warranties made in the Loan Agreement or any other Credit
Document, including, without limitation, any document furnished in connection
with this Amendment, shall survive the execution and delivery of this Amendment
and the other Credit Documents, and no investigation by Agent or any closing
shall affect the representations and warranties or the right of Agent to rely
upon them.

         5.02     REFERENCE TO LOAN AGREEMENT. Each of the Loan Agreement and
the other Credit Documents, and any and all other Credit Documents, documents or
instruments now or hereafter executed and delivered pursuant to the terms hereof
or pursuant to the terms of the Loan Agreement, as amended hereby, are hereby
amended so that any reference in the Loan Agreement and such other Credit
Documents to the Loan Agreement shall mean a reference to the Loan Agreement, as
amended hereby.

         5.03     EXPENSES OF AGENT. As provided in the Loan Agreement, the
Borrower agrees to pay on demand all reasonable costs and expenses incurred by
Agent in connection with the preparation, negotiation, and execution of this
Amendment and the other Credit Documents executed pursuant hereto and any and
all amendments, modifications, and supplements thereto, including, without
limitation, the reasonable costs and fees of Agent's legal counsel, and all
reasonable costs and expenses incurred by Agent in connection with the
enforcement or preservation of any rights under the Loan Agreement, as amended
hereby, or any other Credit Documents, including, without limitation, the
reasonable costs and fees of Agent's legal counsel.

         5.04     SEVERABILITY. Any provision of this Amendment held by a court
of competent jurisdiction to be invalid or unenforceable shall not impair or
invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable.

         5.05     SUCCESSORS AND ASSIGNS. This Amendment is binding upon and
shall inure to the benefit of Agent, the Lenders, and the Credit Parties and
their respective successors and assigns,

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except that the Credit Parties may not assign or transfer any of their rights or
obligations hereunder without the prior written consent of Agent.

         5.06     COUNTERPARTS. This Amendment may be executed in one or more
counterparts, each of which when so executed shall be deemed to be an original,
but all of which when taken together shall constitute one and the same
instrument.

         5.07     EFFECT OF WAIVER. No consent or waiver, express or implied, by
Agent to or for any breach of or deviation from any covenant or condition by the
Credit Parties shall be deemed a consent to or waiver of any other breach of the
same or any other covenant, condition or duty.

         5.08     HEADINGS. The headings, captions, and arrangements used in
this Amendment are for convenience only and shall not affect the interpretation
of this Amendment.

         5.09     APPLICABLE LAW. THIS AMENDMENT AND ALL OTHER CREDIT DOCUMENTS
EXECUTED PURSUANT HERETO SHALL BE DEEMED TO HAVE BEEN MADE AND TO BE PERFORMABLE
IN AND SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE
STATE OF NEW YORK.

         5.10     FINAL AGREEMENT. THE AGREEMENT AND THE OTHER CREDIT DOCUMENTS,
EACH AS AMENDED HEREBY, REPRESENT THE ENTIRE EXPRESSION OF THE PARTIES WITH
RESPECT TO THE SUBJECT MATTER HEREOF ON THE DATE THIS AMENDMENT IS EXECUTED. THE
LOAN AGREEMENT AND THE OTHER CREDIT DOCUMENTS, AS AMENDED HEREBY, MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS
OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES. NO
MODIFICATION, RESCISSION, WAIVER, RELEASE OR AMENDMENT OF ANY PROVISION OF THIS
AMENDMENT SHALL BE MADE, EXCEPT BY A WRITTEN AGREEMENT SIGNED BY THE CREDIT
PARTIES AND THE AGENT.

         5.11     FINANCING STATEMENTS. Agent is hereby authorized by each
Credit Parties to file (including pursuant to the applicable terms of the UCC)
from time to time any financing statements, continuations or amendments covering
the Collateral whether or not the signature of any such Credit Party appears
thereon.

         5.12     RELEASE BY BORROWER. THE BORROWER HEREBY ACKNOWLEDGES THAT
BORROWER HAS NO DEFENSE, COUNTERCLAIM, OFFSET, CROSS-COMPLAINT, CLAIM OR DEMAND
OF ANY KIND OR NATURE WHATSOEVER THAT CAN BE ASSERTED TO REDUCE OR ELIMINATE ALL
OR ANY PART OF ITS LIABILITY TO REPAY THE "OBLIGATIONS" OR TO SEEK AFFIRMATIVE
RELIEF OR DAMAGES OF ANY KIND OR NATURE FROM AGENT OR THE LENDERS. THE BORROWER
HEREBY VOLUNTARILY AND KNOWINGLY RELEASE AND FOREVER DISCHARGE AGENT AND THE
LENDERS, AND THEIR RESPECTIVE PREDECESSORS, AGENTS, EMPLOYEES, SUCCESSORS AND
ASSIGNS (THE "RELEASED PARTIES"), FROM ALL POSSIBLE CLAIMS, DEMANDS, ACTIONS,
CAUSES OF ACTION, DAMAGES, COSTS, EXPENSES, AND LIABILITIES WHATSOEVER, KNOWN OR

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UNKNOWN, ANTICIPATED OR UNANTICIPATED, SUSPECTED OR UNSUSPECTED, FIXED,
CONTINGENT, OR CONDITIONAL, AT LAW OR IN EQUITY, ORIGINATING IN WHOLE OR IN PART
ON OR BEFORE THE DATE THIS AMENDMENT IS EXECUTED, WHICH THE BORROWER MAY NOW OR
HEREAFTER HAVE AGAINST THE RELEASED PARTIES, IF ANY, AND IRRESPECTIVE OF WHETHER
ANY SUCH CLAIMS ARISE OUT OF CONTRACT, TORT, VIOLATION OF LAW OR REGULATIONS, OR
OTHERWISE, AND ARISING FROM ANY "LOANS", INCLUDING, WITHOUT LIMITATION, ANY
CONTRACTING FOR, CHARGING, TAKING, RESERVING, COLLECTING OR RECEIVING INTEREST
IN EXCESS OF THE HIGHEST LAWFUL RATE APPLICABLE, THE EXERCISE OF ANY RIGHTS AND
REMEDIES UNDER THE LOAN AGREEMENT OR OTHER CREDIT DOCUMENTS, AND NEGOTIATION FOR
AND EXECUTION OF THIS AMENDMENT.

         5.13     RELEASE BY GUARANTORS. Each Guarantor hereby consents to the
terms of this Amendment, confirms and ratifies the terms of the guarantee by
such Guarantor for the benefit of Agent and the other Lenders set forth in
Section 13 of the Loan Agreement (each a "Guarantee" and collectively the
"Guarantees"), and acknowledges that such Guarantor's Guarantee is in full force
and effect and ratifies the same and that such Guarantor each has no defense,
counterclaim, set-off or any other claim to diminish such Guarantor's liability
under its Guarantee. EACH GUARANTOR HEREBY VOLUNTARILY AND KNOWINGLY RELEASES
AND FOREVER DISCHARGES THE RELEASED PARTIES, FROM ALL POSSIBLE CLAIMS, DEMANDS,
ACTIONS, CAUSES OF ACTION, DAMAGES, COSTS, EXPENSES, AND LIABILITIES WHATSOEVER,
KNOWN OR UNKNOWN, ANTICIPATED OR UNANTICIPATED, SUSPECTED OR UNSUSPECTED, FIXED,
CONTINGENT, OR CONDITIONAL, AT LAW OR IN EQUITY, ORIGINATING IN WHOLE OR IN PART
ON OR BEFORE THE DATE THIS AMENDMENT IS EXECUTED, WHICH THE GUARANTORS MAY NOW
OR HEREAFTER HAVE AGAINST THE RELEASED PARTIES, IF ANY, AND IRRESPECTIVE OF
WHETHER ANY SUCH CLAIMS ARISE OUT OF CONTRACT, TORT, VIOLATION OF LAW OR
REGULATIONS, OR OTHERWISE, AND ARISING FROM ANY "LOANS", INCLUDING, WITHOUT
LIMITATION, ANY CONTRACTING FOR, CHARGING, TAKING, RESERVING, COLLECTING OR
RECEIVING INTEREST IN EXCESS OF THE HIGHEST LAWFUL RATE APPLICABLE, THE EXERCISE
OF ANY RIGHTS AND REMEDIES UNDER THE LOAN AGREEMENT OR OTHER CREDIT DOCUMENTS,
AND NEGOTIATION FOR AND EXECUTION OF THIS AMENDMENT.

         IN WITNESS WHEREOF, this Amendment has been executed and is effective
as of the date first above-written.

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                                   BORROWER:

                                   GREY WOLF DRILLING COMPANY L.P.

                                   By: Grey Wolf Holdings Company,
                                       its general partner

                                   By: ______________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

                                   GUARANTORS:

                                   GREY WOLF, INC.

                                   By: _________________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

                                   GREY WOLF HOLDINGS COMPANY

                                   By: _________________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

                                   GREY WOLF LLC,

                                   By: _________________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

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                                   DI ENERGY, INC.

                                   By: _________________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

                                   GREY WOLF INTERNATIONAL, INC.

                                   By: _________________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

                                   DI/PERFENSA, INC.

                                   By: _________________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

                                   MURCO DRILLING CORP.

                                   By: _________________________________________
                                       David W. Wehlmann
                                       Senior Vice President and
                                       Chief Financial Officer

                                   LENDERS:

                                   THE CIT GROUP/BUSINESS CREDIT, INC.
                                   as Agent and Lender


                                   By:__________________________________________
                                   Name:________________________________________
                                   Title:_______________________________________

                                   Revolving Loan Commitment:  $40,000,000

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                                   FOOTHILL CAPITAL CORPORATION,
                                   as Lender

                                   By:_________________________________________
                                   Name:_______________________________________
                                   Title:______________________________________

                                   Revolving Loan Commitment:  $35,000,000

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