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                                                                 Exhibit 10.8(b)

                      SECOND AMENDMENT TO CREDIT AGREEMENT

     THIS SECOND AMENDMENT TO CREDIT AGREEMENT (this "Second Amendment"), dated
as of February 3, 2006, is entered into among W-H ENERGY SERVICES, INC., a Texas
corporation (the "Borrower"), each Subsidiary Guarantor, the lenders listed on
the signature pages hereof as Lenders (the "Lenders"), and WELLS FARGO BANK,
NATIONAL ASSOCIATION, as Administrative Agent, Swing Line Lender and Issuer.

                                   BACKGROUND

     A. The Borrower, the Lenders and the Administrative Agent are parties to
that certain Credit Agreement, dated as of June 30, 2004, as amended by that
certain First Amendment to Credit Agreement, dated as of May 5, 2005 (the
"Credit Agreement"). The terms defined in the Credit Agreement and not otherwise
defined herein shall be used herein as defined in the Credit Agreement.

     B. The Borrower has requested an amendment to the Credit Agreement with
respect to Capital Expenditures.

     C. The Lenders and the Administrative Agent hereby agree to amend the
Credit Agreement, subject to the terms and conditions set forth herein.

     NOW, THEREFORE, in consideration of the covenants, conditions and
agreements hereafter set forth, and for other good and valuable consideration,
the receipt and adequacy of which are all hereby acknowledged, the Borrower, the
Subsidiary Guarantors, the Lenders and the Administrative Agent covenant and
agree as follows:

     1. AMENDMENTS.

     (a) Section 7.2.7 of the Credit Agreement is hereby amended to read as
follows:

          Section 7.2.7 Capital Expenditures, etc. The Borrower will not, and
     will not permit any of its Subsidiaries to, make or commit to make Capital
     Expenditures in Fiscal Year 2006 or in any Fiscal Year thereafter in excess
     of $150,000,000 in aggregate amount.

     (b) Exhibit F, the Compliance Certificate, is hereby amended to be in the
form of Exhibit F hereto.

     2. REPRESENTATIONS AND WARRANTIES TRUE; NO EVENT OF DEFAULT. By its
execution and delivery hereof, the Borrower represents and warrants that, as of
the date hereof:

     (a) the representations and warranties contained in the Credit Agreement
and the other Loan Documents are true and correct in all material respects on
and as of the date hereof as made on and as of such date (unless stated to
relate solely to an earlier date, in which case such


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representations and warranties shall be true and correct in all material
respects as of such earlier date);

     (b) no event has occurred and is continuing which constitutes a Default or
an Event of Default;

     (c) (i) the Borrower has full power and authority to execute and deliver
this Second Amendment, (ii) this Second Amendment has been duly executed and
delivered by the Borrower, and (iii) this Second Amendment and the Credit
Agreement, as amended hereby, constitute the legal, valid and binding
obligations of the Borrower, enforceable in accordance with their respective
terms, except as enforceability may be limited by applicable Debtor Relief Laws
and by general principles of equity (regardless of whether enforcement is sought
in a proceeding in equity or at law) and except as rights to indemnity may be
limited by federal or state securities laws;

     (d) neither the execution, delivery and performance of this Second
Amendment, or the Credit Agreement, as amended hereby, nor the consummation of
any transactions contemplated herein or therein, will conflict with or
contravene (i) any Organizational Document of the Borrower, (ii) any law or
governmental regulation or court decree or order binding on or affecting the
Borrower that could reasonably be expected to have a Material Adverse Effect, or
(iii) any indenture, agreement or other instrument to which the Borrower or any
of its property is subject, that could reasonably be expected to have a Material
Adverse Effect; and

     (e) no authorization, approval, consent, or other action by, notice to, or
filing with, any governmental authority or other Person not previously obtained
or made is required for the (i) due execution, delivery or performance by the
Borrower of this Second Amendment, or (ii) the acknowledgment by any Subsidiary
Guarantor of this Second Amendment.

     3. CONDITIONS TO EFFECTIVENESS. This Second Amendment shall be effective
upon satisfaction or completion of the following (for the avoidance of doubt,
the Borrower shall comply with Section 7.2.7 of the Credit Agreement without
giving effect to this Second Amendment for the 2005 Fiscal Year):

     (a) the Administrative Agent shall have received counterparts of this
Second Amendment executed by Lenders comprising the Required Lenders;

     (b) the Administrative Agent shall have received counterparts of this
Second Amendment executed by the Borrower and acknowledged by each Subsidiary
Guarantor; and

     (c) the Administrative Agent shall have received, in form and substance
satisfactory to the Administrative Agent and its counsel, such other documents,
certificates and instruments as the Administrative Agent shall require.


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     4. REFERENCE TO THE CREDIT AGREEMENT.

     (a) Upon the effectiveness of this Second Amendment, each reference in the
Credit Agreement to "this Agreement", "hereunder", or words of like import shall
mean and be a reference to the Credit Agreement, as affected and amended hereby.

     (b) The Credit Agreement, as amended by the amendments referred to above,
shall remain in full force and effect and is hereby ratified and confirmed.

     5. COSTS, EXPENSES AND TAXES. The Borrower agrees to pay on demand all
out-of-pocket costs and expenses of the Administrative Agent in connection with
the preparation, reproduction, execution and delivery of this Second Amendment
and the other instruments and documents to be delivered hereunder (including the
reasonable fees and out-of-pocket expenses of counsel for the Administrative
Agent with respect thereto).

     6. SUBSIDIARY GUARANTOR'S ACKNOWLEDGMENT. By signing below, each Subsidiary
Guarantor (a) acknowledges, consents and agrees to the execution, delivery and
performance by the Borrower of this Second Amendment, (b) acknowledges and
agrees that its obligations in respect of its Subsidiary Guaranty are not
released, diminished, waived, modified, impaired or affected in any manner by
this Second Amendment or any of the provisions contemplated herein, (c) ratifies
and confirms its obligations under its Subsidiary Guaranty, and (d) acknowledges
and agrees that it has no claims or offsets against, or defenses or
counterclaims to, its Subsidiary Guaranty.

     7. EXECUTION IN COUNTERPARTS. This Second Amendment may be executed in any
number of counterparts and by different parties hereto in separate counterparts,
each of which when so executed and delivered shall be deemed to be an original
and all of which when taken together shall constitute but one and the same
instrument. For purposes of this Second Amendment, a counterpart hereof (or
signature page thereto) signed and transmitted by any Person party hereto to the
Administrative Agent (or its counsel) by facsimile machine, telecopier or
electronic mail is to be treated as an original. The signature of such Person
thereon, for purposes hereof, is to be considered as an original signature, and
the counterpart (or signature page thereto) so transmitted is to be considered
to have the same binding effect as an original signature on an original
document.

     8. GOVERNING LAW; BINDING EFFECT. This Second Amendment shall be governed
by and construed in accordance with the internal laws of the State of Texas,
provided that each party shall retain all rights arising under federal law, and
shall be binding upon the parties hereto and their respective successors and
assigns.

     9. HEADINGS. Section headings in this Second Amendment are included herein
for convenience of reference only and shall not constitute a part of this Second
Amendment for any other purpose.

     10. ENTIRE AGREEMENT. THE CREDIT AGREEMENT, AS AMENDED BY THIS SECOND
AMENDMENT, AND THE OTHER LOAN DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN
THE PARTIES AND MAY NOT BE


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CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS BETWEEN THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN
THE PARTIES.

                   REMAINDER OF PAGE LEFT INTENTIONALLY BLANK


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     IN WITNESS WHEREOF, this Second Amendment is executed as of the date first
set forth above.

                                        W-H ENERGY SERVICES, INC.


                                        By: /s/ Jeffrey L. Tepera
                                            ------------------------------------
                                        Name: Jeffrey L. Tepera
                                        Title: Vice President and
                                               Chief Financial Officer


                                        WELLS FARGO BANK, NATIONAL ASSOCIATION,
                                        as  Administrative  Agent,  as Swing
                                        Line Lender, as Issuer and as Lender


                                        By: /s/ Eric R. Hollingsworth
                                            ------------------------------------
                                        Name: Eric R. Hollingsworth
                                        Title: Vice President


                                        JPMORGAN CHASE BANK, NA,
                                        successor by merger with Bank One, NA,
                                        as Co-Syndication Agent and as a Lender


                                        By: /s/ Dianne L. Russell
                                            ------------------------------------
                                        Name: Dianne L. Russell
                                        Title: Vice President


                                        THE BANK OF NOVA SCOTIA,
                                        as Co-Documentation Agent and as
                                        a Lender


                                        By: /s/ William E. Zarrett
                                            ------------------------------------
                                        Name: William E. Zarrett
                                        Title: Managing Director


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                                        COMERICA BANK,
                                        as Co-Syndication Agent and as a Lender


                                        By: /s/ Mona M. Foch
                                            ------------------------------------
                                        Name: Mona M. Foch
                                        Title: Senior Vice President-Texas
                                               Division


                                        CITIBANK TEXAS, N.A.,
                                        formerly known as First American Bank,
                                        S.S.B., as Managing Agent and as
                                        a Lender


                                        By: /s/ Dale T. Wilson
                                            ------------------------------------
                                        Name: Dale T. Wilson
                                        Title: Senior Vice President


                                        WACHOVIA BANK, NATIONAL ASSOCIATION,
                                        as Co-Documentation Agent and as
                                        a Lender


                                        By: /s/ Michael S. Hodges
                                            ------------------------------------
                                        Name: Michael S. Hodges
                                        Title: Vice President


                                        SCOTIABANC INC.


                                        By: /s/ William E. Zarrett
                                            ------------------------------------
                                        Name: William E. Zarrett
                                        Title: Managing Director


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                                        BANK OF SCOTLAND


                                        By: /s/ Karen Weich
                                            ------------------------------------
                                        Name: Karen Weich
                                        Title: Assistant Vice President


                                        DnB NOR BANK ASA


                                        By: /s/ Peter M. Dodge
                                            ------------------------------------
                                        Name: Peter M. Dodge
                                        Title: Senior Vice President


                                        By: /s/ Stig Kristiansen
                                            ------------------------------------
                                        Name: Stig Kristiansen
                                        Title: Vice President


                                        HIBERNIA NATIONAL BANK


                                        By: /s/ Stephen H Birnbaum
                                            ------------------------------------
                                        Name: Stephen H. Birnbaum
                                        Title: Vice President


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                                        NATEXIS BANQUES POPULAIRES


                                        By: /s/ Timothy L. Polvado
                                            ------------------------------------
                                        Name: Timothy L. Polvado
                                        Title: Vice President and Group Manager


                                        By: /s/ Daniel Payer
                                            ------------------------------------
                                        Name: Daniel Payer
                                        Title: Vice President


                                        REGIONS BANK,
                                        successor by merger with
                                        Union Planters Bank NA


                                        By: /s/ B. Forrest Taylor
                                            ------------------------------------
                                        Name: B. Forrest Taylor
                                        Title: Sr. Vice President


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ACKNOWLEDGED AND AGREED:

AGRI-EMPRESA, INC.
AGRI-EMPRESA TRANSPORTATION, INC.
BOYD'S BIT SERVICE, INC.
BOYD'S HOLDINGS, L.L.C.
COIL TUBING SERVICES, L.L.C.
DIAMOND WIRELINE SERVICES, INC.
DRILL MOTOR SERVICES, INC.
DUTCH, INC.
DYNA DRILL TECHNOLOGIES, INC.
GRINDING AND SIZING COMPANY, INC.
INTEGRITY INDUSTRIES, INC.
PATHFINDER ENERGY HOLDINGS, INC.
PATHFINDER ENERGY, INC.
PATHFINDER MEXICO HOLDINGS, L.L.C.
PATHFINDER ENERGY SERVICES HOLDINGS, INC.
PATHFINDER ENERGY SERVICES, INC.
PERF-O-LOG, INC.
STG TRANSPORTATION, INC.
SUPERIOR LONESTAR GP, L.L.C.
SUPERIOR LONESTAR LP, L.L.C.
THOMAS ENERGY SERVICES, INC.
W-H ACQUISITIONS, LLC
W-H DRILLING SOLUTIONS, INC.
W-H ENERGY HOLDINGS, INC.
W-H ENERGY HOLDINGS II, INC.
WHES MANAGEMENT, INC.
E. M. HOBBS, L.P.
   By: W-H Acquisitions, LLC
LSDI, L.P.
   By: Superior Lonestar GP, L.L.C.
PATHFINDER ENERGY SERVICES, LP
   By: Pathfinder Energy, Inc.
PATHFINDER INTERNATIONAL, L.P.
   By: WHES Management, Inc.
SUPERIOR PACKAGING & DISTRIBUTION, L.P.
   By: Superior Lonestar GP, L.L.C.
U.S. CLAY, L.P.
   By: Agri-Empresa, Inc.
W-H ENERGY FINANCING, L.P.
   By: WHES Management, Inc.


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W-H ENERGY SERVICES, L.P.
   By: WHES Management, Inc.


By: /s/ Ernesto Bautista III
    ---------------------------------
    Ernesto Bautista III
    Vice President and Assistant
    Secretary for all


WHES PARTNERS, INC.


By: /s/ Kenneth T. White, Jr.
    ---------------------------------
    Kenneth T. White, Jr.
    President


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