**Exhibit4.2**

 

**FIRSTAMENDMENT TO AMENDED AND RESTATED LOAN AGREEMENT**

 

THIS FIRST AMENDMENT TOAMENDED AND RESTATED LOAN AGREEMENT (the “First Amendment”) is enteredinto as of January 29, 2004, by and between **PIONEER DRILLING SERVICES, LTD.**, a Texas limited partnership (“PioneerServices”), **PIONEER DRILLING COMPANY**, a Texas corporation (“PioneerCompany”), (Pioneer Services and Pioneer Company being collectivelyreferred to herein as “Pioneer”) and **THE FROST NATIONAL BANK**, anational banking association (“Lender”).

 

RECITALS

 

A.                                   Onor about December 15, 2003, Pioneer Services, Pioneer Company and Lenderentered into that certain Amended and Restated Loan Agreement (the “LoanAgreement”), concerning, among other things, the terms, conditions andcovenants of those certain Credit Facilities (as defined in the LoanAgreement).

 

B.                                     Borrowerand Lender have agreed to further amend the Loan Agreement as contained herein.

 

C.                                     Allcapitalized terms not otherwise defined in this First Amendment shall have thesame meanings as are set forth in the Loan Agreement.

 

NOW, THEREFORE, for andin consideration of the premises and mutual covenants herein contained andother good and valuable consideration, the receipt and sufficiency of which arehereby acknowledged, Borrower and Lender hereby agree as follows:

 

AGREEMENTS

 

1.                                       Amendment.  Section 8(f) of the Loan Agreement ishereby amended in its entirety to read as follows:

 

(f)                                    Transfer of Ownership. Permit the sale, pledge or other transfer of any of the ownershipinterests in Pioneer Services.

 

2.                                       NoOther Amendment.  Except asspecifically modified or amended herein, all terms, provisions and requirementsof the Loan Agreement shall remain as written, and as amended from time totime.

 

3.                                       Reaffirmation.  Borrower hereby reaffirms all covenants,conditions, representations and warranties contained in the Loan Agreement, asamended by this First Amendment.

 

NOTICE TO COMPLYWITH STATE LAW

 

For the purpose of thisNotice, the term “WRITTEN AGREEMENT” shall include the document set forthabove, together with each and every other document relating to and/or securingthe same loan transaction, regardless of the date of execution.

 

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**NOTICEOF FINAL AGREEMENT**

 

**THISWRITTEN AGREEMENT REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAYNOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORALAGREEMENTS OF THE PARTIES.**

 

**THEREARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.**

 

 

**[Balanceof Page Intentionally Left Blank]**

 

**[Signature(s)on Following Page(s)]**

 

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IN WITNESS WHEREOF, theparties hereto have caused this First Amendment to be duly executed as of thedate first above written.

 
|   | LENDER:                                                          |
|--------|------------------------------------------------------------------|
|   |                                                             |
|   | **THE  FROST NATIONAL BANK,******a national banking association  |
|   |                                                             |
|   | /s/ W. Casey Shaeffer                                            |
|   | W. Casey Shaeffer                                                |
|   | Vice President                                                   |
|   |                                                             |   |
|   | PIONEER SERVICES:                                                |
|   |                                                             |   |
|   | **PIONEER  DRILLING SERVICES, LTD.,**a Texas limited partnership |
|   |                                                             |   |
|   | By:                                                              | PDC Mgmt. Co., a Texas  corporation, General Partner |
|   |                                                             |   |
|   |                                                             | /s/  Wm. Stacy Locke |
|   |                                                             | Wm. Stacy Locke |
|   |                                                             | President and Chief  Executive Officer |
|   |                                                             |   |
|   |                                                             |   |
|   | PIONEER COMPANY:                                                 |
|   |                                                             |   |
|   | **PIONEER  DRILLING COMPANY,**a Texas corporation                |
|   |                                                             |
|   |                                                             | /s/  Wm. Stacy Locke |
|   |                                                             | Wm. Stacy Locke |
|   |                                                             | President and Chief  Executive Officer |

 

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