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EXHIBIT 2.1

ASSET PURCHASE AGREEMENT

BETWEEN

PATTERSON DRILLING COMPANY

AND

ZIADRIL, INC.
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TABLE OF CONTENTS

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ARTICLE I

THE ASSET PURCHASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1-
SECTION 1.1 The Asset Purchase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1-
SECTION 1.2 Purchase Price . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1-
SECTION 1.3 Closing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -2-

ARTICLE II

REPRESENTATIONS AND WARRANTIES OF PDC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -2-
SECTION 2.1 Organization, Standing and Power . . . . . . . . . . . . . . . . . . . . . . -2-
SECTION 2.2 Authority; Non-Contravention . . . . . . . . . . . . . . . . . . . . . . . . -2-

ARTICLE III

REPRESENTATIONS AND WARRANTIES OF ZIADRIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -2-
SECTION 3.1 Organization, Standing and Power. . . . . . . . . . . . . . . . . . . . . . . -2-
SECTION 3.2 Authority; Non-Contravention. . . . . . . . . . . . . . . . . . . . . . . . . -3-
SECTION 3.3 Environmental Matters . . . . . . . . . . . . . . . . . . . . . . . . . . . . -3-
SECTION 3.4 Title. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -5-
SECTION 3.5 Drilling Contracts and Other Agreements. . . . . . . . . . . . . . . . . . -5-
SECTION 3.6 Litigation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -5-
SECTION 3.7 Brokers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -5-
SECTION 3.8 Normal Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -5-
SECTION 3.9 Stock Ownership and Control. . . . . . . . . . . . . . . . . . . . . . . . . -5-

ARTICLE IV

ADDITIONAL AGREEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6-
SECTION 4.1 Fees and Expenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6-
SECTION 4.2 Reasonable Efforts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6-
SECTION 4.3 ZIADRIL Indemnification . . . . . . . . . . . . . . . . . . . . . . . . . . . -6-
SECTION 4.4 Public Announcements . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6-
SECTION 4.5 PDC Assumption of Drilling Contracts; ZIADRIL Invoicing of Direct Costs. . . -6-
SECTION 4.6 PDC Indemnification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6-
SECTION 4.7 Sales and Transfer Taxes. . . . . . . . . . . . . . . . . . . . . . . . . . . -7-
SECTION 4.8 Real Estate Taxes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -7-

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ARTICLE V

CONDITIONS PRECEDENT TO THE ASSET PURCHASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . -7-
SECTION 5.1 Conditions to Each Party's Obligation to Effect the Asset Purchase . . . . . -7-
SECTION 5.2 Conditions to Obligation of ZIADRIL to Effect the Asset Purchase . . . . . . -7-
SECTION 5.3 Conditions to Obligations of PDC to Effect the Asset Purchase . . . . . . . . -8-

ARTICLE VI

GENERAL PROVISIONS . . . . . . . . . . . . . . -10-
SECTION 6.1 Notices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -10-
SECTION 6.2 Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -10-
SECTION 6.3 Counterparts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -11-
SECTION 6.4 Entire Agreement; No Third-Party Beneficiaries . . . . . . . . . . . . . . . -11-
SECTION 6.5 Governing Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -11-
SECTION 6.6 Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -11-
SECTION 6.7 Severability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -11-
SECTION 6.8 Enforcement of This Agreement . . . . . . . . . . . . . . . . . . . . . . . . -11-

ANNEX 1 Description of Drilling Rigs, Equipment and Vehicles
ANNEX 2 Description of Real Property
ANNEX 3 List of Drilling Contracts and Other Agreements
ANNEX 4 List of ZIADRIL Stockholders

EXHIBIT A(I) Non-Competition Agreement - ZIADRIL, Inc.
EXHIBIT A(II) Non-Competition Agreement - Joe Smith
EXHIBIT A(III) Non-Competition Agreement - Ken Bromley
EXHIBIT A(IV) Non-Competition Agreement - Billy Jensen
EXHIBIT A(V) Non-Competition Agreement - Lee Roberson
EXHIBIT B Bill of Sale and Assignment
EXHIBIT C(I) Warranty Deed - West County Road Property
EXHIBIT C(II) Warranty Deed - Marland Street Property

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ASSET PURCHASE AGREEMENT

ASSET PURCHASE AGREEMENT, dated as of April 22, 1997 (this
"Agreement"), among PATTERSON DRILLING COMPANY ("PDC"), a Delaware corporation
and a wholly-owned subsidiary of Patterson Energy, Inc. ("PEC"), and ZIADRIL,
INC., a privately-held New Mexico corporation ("ZIADRIL").

WITNESSETH:

WHEREAS, ZIADRIL owns five drilling rigs, related drilling equipment
and office equipment and vehicles (collectively, the "Drilling Rigs, Equipment
and Vehicles"), and two parcels of real property owned by ZIADRIL on West
County Road (the "West County Road Property") and Marland Street (the "Marland
Street Property"), respectively, in Hobbs, New Mexico (collectively, the "Real
Property"), all as more particularly described on Annex 1, in the case of the
Drilling Rigs, Equipment and Vehicles and Annex 2, in the case of the Real
Property;

WHEREAS, PDC desires to purchase, and ZIADRIL desires to sell, all of
ZIADRIL's right, title and interest in and to the Drilling Rigs, Equipment and
Vehicles and in the Real Property (the "Asset Purchase") for the consideration
set forth and provided for herein; and

WHEREAS, PDC, on the one hand, and ZIADRIL, on the other, desire to
make certain representations, warranties and agreements in connection with the
Asset Purchase.

NOW, THEREFORE, in consideration of the premises and the
representations, warranties and agreements herein contained, the parties agree
as follows:

ARTICLE I

THE ASSET PURCHASE

SECTION 1.1 The Asset Purchase. Upon the terms and subject to the
conditions of this Agreement, at the Closing (as defined in Section 1.3 below)
provided herein, PDC shall purchase from ZIADRIL and ZIADRIL shall sell to PDC,
all of ZIADRIL's right, title and interest in and to the Real Property and in
and to the Drilling Rigs, Equipment and Vehicles "as is, where is," with no
representation or warranty as to condition.
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SECTION 1.2 Purchase Price. PDC agrees to pay to ZIADRIL at the
Closing a total of $3,500,000 (the "Purchase Price") for all of ZIADRIL's
right, title and interest in and to the Drilling Rigs, Equipment and Vehicles
and in and to the Real Property. The Purchase Price shall be paid by cashier's
check.

SECTION 1.3 Closing. The closing of the Asset Purchase (the
"Closing") shall take place at 9:00 a.m., local time, on the date of this
Agreement at the offices of Patterson Energy, Inc., in Snyder, Texas or at such
other time and place as PDC and ZIADRIL shall agree.

ARTICLE II

REPRESENTATIONS AND WARRANTIES OF PDC

PDC represents and warrants to ZIADRIL as follows:

SECTION 2.1 Organization, Standing and Power. PDC is a corporation
duly incorporated, validly existing and in good standing under the laws of the
State of Delaware and has the requisite corporate power and authority to carry
on its business as now being conducted.

SECTION 2.2 Authority; Non-Contravention. PDC has all requisite
power and authority to enter into this Agreement and to consummate the Asset
Purchase. The execution and delivery by PDC of this Agreement and the
consummation by PDC of the Asset Purchase have been duly authorized by all
necessary corporate action on the part of PDC. This Agreement has been duly
executed and delivered by PDC and (assuming the valid authorization, execution
and delivery of this Agreement by ZIADRIL) constitutes a valid and binding
obligation of PDC enforceable against PDC in accordance with its terms, except
to the extent enforceability may be limited by bankruptcy, insolvency,
reorganization, moratorium, fraudulent transfer or other similar laws of
general applicability relating to or affecting the enforcement of creditors'
rights and by the effect of general principles of equity (regardless of whether
enforceability is considered in a proceeding in equity or at law). No filing
or registration with, or authorization, consent or approval of, any domestic
(federal and state), foreign or supranational court, commission, governmental
body, regulatory agency, authority or tribunal (a "Governmental Agency") is
required by or with respect to PDC in connection with the execution and
delivery of this Agreement by PDC or is necessary for the consummation by PDC
of the Asset Purchase.

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ARTICLE III

REPRESENTATIONS AND WARRANTIES OF ZIADRIL

SECTION 3.1 Organization, Standing and Power. ZIADRIL is a
corporation duly incorporated, validly existing and in good standing under the
laws of the State of New Mexico and has the requisite corporate power and
authority to carry on its business as now being conducted.

SECTION 3.2 Authority; Non-Contravention. ZIADRIL has all requisite
power and authority to enter into this Agreement and to consummate the Asset
Purchase. This Agreement has been duly executed and delivered by ZIADRIL and
(assuming the valid authorization, execution and delivery of this Agreement by
PDC) constitutes a valid and binding obligation of ZIADRIL enforceable against
it in accordance with its terms, except to the extent enforceability may be
limited by bankruptcy, insolvency, reorganization, moratorium, fraudulent
transfer or other similar laws of general applicability relating to or
affecting the enforcement of creditors' rights and by the effect of general
principles of equity (regardless of whether enforceability is considered in a
proceeding in equity or at law). The execution and delivery of this Agreement
do not, and the consummation of the Asset Purchase and compliance with the
provisions hereof will not, conflict with, or result in any violation of, or
default (with or without notice of lapse of time, or both) under, or give rise
to a right of termination, cancellation or acceleration of any obligation or to
the loss of a material benefit under, or result in the creation of any lien,
security interest, charges or encumbrances upon any of the properties or assets
of ZIADRIL under, any provision of (i) the Articles of Incorporation or Bylaws
of ZIADRIL (true and complete copies of which as of the date hereof have been
delivered to PDC), (ii) any loan or credit agreement, note, bond, mortgage,
indenture, lease or other agreement, instrument, permit, concession, franchise
or license applicable to ZIADRIL or (iii) any judgment, order, decree, statute,
law, ordinance, rule or regulation applicable to ZIADRIL or any of its
respective properties or assets. No filing or registration with, or
authorization, consent or approval of, any Governmental Entity is required by
or with respect to ZIADRIL in connection with the execution and delivery of
this Agreement by ZIADRIL or is necessary for the consummation by ZIADRIL of
the Asset Purchase.

SECTION 3.3 Environmental Matters.

(a) Except to the extent that the inaccuracy of any of
the following, individually or in the aggregate, would not have a Material
Adverse Effect on ZIADRIL, to the actual knowledge of ZIADRIL:

(i) ZIADRIL holds, and is in compliance with and has been
in compliance with for the last three years, all Environmental
Permits, and is otherwise in substantial compliance and has been in
substantial compliance for the last three years with, all applicable
Environmental Laws and there is no condition that is reasonably likely
to prevent or materially interfere prior to the Effective Time with
compliance by ZIADRIL with Environmental Laws;

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(ii) no modification, revocation, reissuance, alteration,
transfer or amendment of any Environmental Permit, or any review by,
or approval of, any third party of any Environmental Permit is
required in connection with the execution or delivery of this
Agreement or the consummation by ZIADRIL of the transactions
contemplated hereby or the operation of the business of ZIADRIL on the
date of the Closing;

(iii) Except with respect to the two storage tanks removed
from the Marland Street Property, ZIADRIL has not received any
Environmental Claim, nor has any Environmental Claim been threatened
against ZIADRIL;

(iv) ZIADRIL has not entered into, agreed to or is not
subject to any outstanding judgment, decree, order or consent
arrangement with any governmental authority under any Environmental
Laws, including without limitation those relating to compliance with
any Environmental Laws or to the investigation, cleanup, remediation
or removal of Hazardous Materials;

(v) there are no circumstances that are reasonably likely
to give rise to liability under any agreements with any person
pursuant to which ZIADRIL would be required to defend, indemnify, hold
harmless, or otherwise be responsible for any violation by or other
liability or expense of such person, or alleged violation by or other
liability or expense of such person, arising out of any Environmental
Law; and

(vi) there are no other circumstances or conditions that
are reasonably likely to give rise to liability of ZIADRIL under any
Environmental Laws.

(b) For purposes of this Agreement, the terms below shall
have the following meanings:

"Environmental Claim" means any written complaint, notice,
claim, demand, action, suit or judicial, administrative or arbitral
proceeding by any person to ZIADRIL asserting liability or potential
liability (including without limitation, liability or potential
liability for investigatory costs, cleanup costs, governmental
response costs, natural resource damages, property damage, personal
injury, fines or penalties) arising out of, relating to, based on or
resulting from (i) the presence, discharge, emission, release or
threatened release of any Hazardous Materials at any location, (ii)
circumstances forming the basis of any violation or alleged violation
of any Environmental Laws or Environmental Permits, or (iii) otherwise
relating to obligations or liabilities of ZIADRIL under any
Environmental Law.

"Environmental Permits" means all permits, licenses,
registrations, exemptions and other governmental authorizations
required under Environmental Laws for ZIADRIL to conduct its
operations as presently conducted.

"Environmental Laws" means all applicable foreign, federal,
state and local statutes, rules, regulations, ordinances, orders,
decrees and common law relating in any manner to

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pollution or protection of the environment, to the extent and in the
form that such exist at the date hereof.

"Hazardous Materials" means all hazardous or toxic substances,
wastes, materials or chemicals, petroleum (including crude oil or any
fraction thereof) and petroleum products, asbestos and asbestos-
containing materials, pollutants, contaminants and all other materials
and substances, including but not limited to radioactive materials,
regulated pursuant to any Environmental Laws.

"Material Adverse Effect" means any change or effect that is
or, as far as can reasonably be determined, is likely to be materially
adverse to the assets, properties, conditions (financial or
otherwise), business or results of operations of ZIADRIL.

SECTION 3.4 Title. Set forth in Annex 1 and Annex 2 is a description
of the Drilling Rigs, Equipment and Vehicles and of the Real Property,
respectively, which description is accurate and complete in all material
respects. ZIADRIL has good and, in the case of the Real Property, indefeasible
title to a 100% interest in the Drilling Rigs, Equipment and Vehicles and in
the Real Property, subject to no Liens except for (i) Liens for taxes not yet
delinquent or the validity of which is being contested in good faith, and (ii)
any Liens arising by operation of law securing obligations not yet overdue.
For purposes of this Agreement "Liens" means liens, mortgages, pledges,
security interests, encumbrances, claims or charges of any kind.

SECTION 3.5 Drilling Contracts and Other Agreements. Set forth in
Annex 3 is a true and complete list of all oral and written drilling contracts
(the "Drilling Contracts") and other agreements (the "Other Agreements")
relating to the Drilling Rigs, Equipment and Vehicles or the Real Property to
which ZIADRIL is a party. A complete copy of each of the Drilling Contracts
and Other Agreements has previously been delivered to PDC. Each of the
Drilling Contracts and the Other Agreements has been fully performed by ZIADRIL
to date, and is in good standing and in full force and effect. Except as set
forth on Annex 3, none of the Real Property or Drilling Rigs, Equipment and
Vehicles is subject to any written or oral contracts and agreements.

SECTION 3.6 Litigation. Other than possible workman's compensation
cases, there is no suit, action, investigation or proceeding pending or, to the
knowledge of ZIADRIL, threatened against ZIADRIL at law or in equity before or
by any federal, state, municipal or other governmental department, commission,
board, bureau, agency or instrumentality, domestic or foreign, or before any
arbitrator of any kind.

SECTION 3.7 Brokers. No broker, investment banker or other person is
entitled to any broker's, finder's or other similar fee or commission in
connection with the transactions contemplated by this Agreement based upon
arrangements made by or on behalf of ZIADRIL.

SECTION 3.8 Normal Operations. All wells currently being drilled by
ZIADRIL under the Drilling Contracts are drilling under normal operations.

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SECTION 3.9 Stock Ownership and Control. No person: (i) beneficially
owns 50 percent or more of the outstanding voting securities of ZIADRIL or (ii)
has the contractual power to designate 50 percent or more of the members of the
ZIADRIL Board of Directors. Annex 4 sets forth a true and correct list of the
holders of ZIADRIL's voting securities and the number of such securities filed
by each such holder.

ARTICLE IV

ADDITIONAL AGREEMENTS

SECTION 4.1 Fees and Expenses. All costs and expenses incurred by
PDC in connection with this Agreement and the transactions contemplated hereby
shall be paid by PDC; such costs and expenses incurred by ZIADRIL shall be paid
by ZIADRIL.

SECTION 4.2 Reasonable Efforts. Upon the terms and subject to the
conditions set forth in this Agreement, each of the parties agrees to use all
reasonable efforts to take, or cause to be taken, all actions, and to do, or
cause to be done, and to assist and cooperate with the other parties in doing,
all things necessary, proper or advisable to consummate and make effective, in
the most expeditious manner practicable, the Asset Purchase and the other
transactions contemplated by this Agreement and the prompt satisfaction of the
conditions hereto.

SECTION 4.3 ZIADRIL Indemnification. On and after the Closing Date,
ZIADRIL, and Joe Smith ("Smith"), Ken Bromley ("Bromley") and Billy Jensen
("Jensen"), each of whom is an officer, director or a stockholder of ZIADRIL,
and Lee Roberson, a consultant to ZIADRIL, shall jointly and severally
indemnify and hold PEC and PDC harmless against and in respect of all actions,
suits, demands, judgments, costs and expenses (including reasonably attorneys'
fees of PEC or PDC), relating to any misrepresentation, breach of any
representation or warranty or non-fulfillment of any agreement on the part of
ZIADRIL contained in this Agreement. This indemnification provided for in this
Section 4.3 shall terminate and be of no further force and effect one and
one-half years from the Closing Date, except as to any representation or
warranty as to which a written notice of claim for indemnification has been
given to ZIADRIL, Smith, Bromley, Jensen and Roberson prior to the expiration
of such one and one-half year period.

SECTION 4.4 Public Announcements. Unless otherwise required by law
or the rules and regulations of the Securities and Exchange Commission, neither
PDC, PEC nor ZIADRIL shall issue any press release or make any public statement
with respect to the Asset Purchase prior to Closing.

SECTION 4.5 PDC Assumption of Drilling Contracts; ZIADRIL Invoicing
of Direct Costs. Effective as of 7:00 a.m. Snyder, Texas time on the date of
this Agreement ("Effective Time of Assumption"), PDC shall assume all
obligations and rights and benefits of ZIADRIL under each of the Drilling
Contracts. In addition, within 30 days following Closing, ZIADRIL shall
invoice PDC for all direct costs (actual third-party charges and labor) plus a
daily proration of the salaries of

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Jensen and Judy Streun and trucking expenses incurred by ZIADRIL under each of
the Drilling Contracts prior to the Effective Time of Assumption, which
invoices shall be paid to ZIADRIL by PDC within 30 days of receipt by PDC.

SECTION 4.6 PDC Indemnification. PDC shall indemnify and hold
ZIADRIL harmless from all costs and liabilities (including reasonable
attorney's fees) incurred by ZIADRIL under any of the Drilling Contracts for
events occurring after the Effective Time of Assumption.

SECTION 4.7 Sales and Transfer Taxes. ZIADRIL agrees to pay any and
all sales and/or transfer taxes due with respect to the Asset Purchase.

SECTION 4.8 Real Estate Taxes. ZIADRIL and PDC agree that general
real estate taxes based on the actual tax bill for the year of Closing and, if
such tax bill is not available, the most recent mill levy and assessment,
rents, water and service charges and any special assessments or other charges
on the Real Property shall be prorated between ZIADRIL and PDC to the date of
Closing. Such prorations shall be final.

ARTICLE V

CONDITIONS PRECEDENT TO THE ASSET PURCHASE

SECTION 5.1 Conditions to Each Party's Obligation to Effect the Asset
Purchase. The respective obligations of each party to effect the Asset
Purchase shall be subject to the fulfillment or waiver (where permissible) at
or prior to the Closing Date of each of the following conditions:

(a) No Order. No Governmental Entity or court of
competent jurisdiction shall have enacted, issued, promulgated, enforced or
entered any law, rule, regulation, executive order, decree, injunction or other
order (whether temporary, preliminary or permanent) which is then in effect and
has the effect of prohibiting the Asset Purchase or any of the other
transactions contemplated hereby; provided that, in the case of any such
decree, injunction or other order, each of the parties shall have used
reasonable best efforts to prevent the entry of any such injunction or other
order and to appeal as promptly as practicable any decree, injunction or other
order that may be entered.

(b) Consents. ZIADRIL shall have received written
consents of the other party or parties to each of the Drilling Contracts for
the assumption thereof by PDC pursuant to the provisions of Section 4.5 of this
Agreement and delivered copies thereof to PDC.

(c) Non-Competition Agreements. A Non-Competition
Agreement in the respective forms attached hereto as Exhibits A(I), A(II),
A(III), A(IV) and A(V) shall have been executed and delivered by ZIADRIL,
Smith, Bromley, Jensen and Roberson, as the case may be.

SECTION 5.2 Conditions to Obligation of ZIADRIL to Effect the Asset
Purchase. The obligation of ZIADRIL to effect the Asset Purchase shall be
subject to the fulfillment at or prior to

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the Closing of the following additional conditions; provided that ZIADRIL may
waive any of such conditions in its sole discretion:

(a) Performance of Obligations; Representations and
Warranties. PDC shall have performed in all material respects each of its
agreements contained in this Agreement required to be performed on or prior to
the Closing, each of the representations and warranties of PDC contained in
this Agreement shall be true and correct on and as of the Closing.

(b) Officers' Certificate. PDC shall have furnished to
ZIADRIL a certificate, dated the Closing, signed by the appropriate officers of
PDC, certifying to the effect that to the best of the knowledge and belief of
PDC, the conditions set forth in Section 5.1 and Section 5.2(a) have been
satisfied in full.

(c) Payment of Purchase Price. PDC shall have made
delivery of the Purchase Price as provided in Section 1.2 of this Agreement.

SECTION 5.3 Conditions to Obligations of PDC to Effect the Asset
Purchase. The obligations of PDC to effect the Asset Purchase shall be subject
to the fulfillment at or prior to the Closing of the following additional
conditions, provided that PDC may waive any such conditions in its sole
discretion:

(a) Performance of Obligations; Representations and
Warranties. ZIADRIL shall have performed in all material respects each of its
agreements contained in this Agreement required to be performed on or prior to
the Closing, each of the respective representations and warranties of ZIADRIL
contained in this Agreement shall be true and correct on and as of the Closing
shall be true in all material respects on and as of the Closing.

(b) Officers' Certificate. ZIADRIL shall have furnished
to PDC a certificate, dated the Closing, certifying to the effect that to the
best of the knowledge and belief of ZIADRIL, the conditions set forth in
Section 5.1 and Section 5.3(a) have been satisfied.

(c) Opinion of Counsel. PDC shall have received an
opinion of counsel from Tommy D. Parker, Esq., Hobbs, New Mexico counsel to
ZIADRIL, dated the Closing, substantially to the effect that:

(i) The incorporation, existence and good standing of
ZIADRIL are as stated in this Agreement.

(ii) This Agreement has been duly authorized, executed and
delivered by ZIADRIL, and (assuming the due and valid authorization,
execution and delivery by PDC) constitutes the legal, valid and
binding agreement of ZIADRIL enforceable against ZIADRIL in accordance
with its terms, except to the extent enforceability may be limited by
bankruptcy, insolvency, reorganization, moratorium, fraudulent
transfer or other similar laws of general applicability relating to or
affecting the enforcement of creditors' rights and by the effect of
general

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principles of equity (regardless of whether enforceability is
considered in a proceeding in equity or at law).

(iii) The execution and performance by ZIADRIL of this
Agreement will not violate the Articles of Incorporation or Bylaws of
ZIADRIL and will not violate, result in a breach of, or constitute a
default under, any material lease, mortgage, contract, agreement,
instrument, law, rule, regulation, judgment, order or decree known to
such counsel to which ZIADRIL is a party or to which it or any of its
properties or assets may be bound.

(iv) To the knowledge of such counsel, there are no
actions, suits or proceedings, pending or threatened against or
affecting ZIADRIL by any Governmental Entity which seek to restrain,
prohibit or invalidate the transactions contemplated by this
Agreement.

(v) To the knowledge of such counsel, no consent,
approval, authorization or order of any court or governmental agency
or body which has not been obtained is required on behalf of ZIADRIL
for consummation of the transactions contemplated by this Agreement.

(vi) Each Non-Competition Agreement between PDC and each
of ZIADRIL, Smith, Bromley, Jensen and Roberson constitutes the legal,
valid and binding agreement of it/him enforceable against it/him in
accordance with its terms, except to the extent enforceability may be
limited by bankruptcy, insolvency, reorganization, moratorium,
fraudulent transfer or other similar laws of general applicability
relating to or affecting the enforcement of creditors' rights and by
the effect of general principles of equity (regardless of whether
enforceability is considered in a proceeding in equity or at law).

In rendering such opinion, counsel for ZIADRIL may rely as to matters of fact
upon the representations of officers of ZIADRIL contained in any certificate
delivered to such counsel and certificates of public officials.

Such opinion shall be limited to the laws of the United States of
America and the State of New Mexico.

(d) Bill of Sale and Assignment. ZIADRIL shall have
executed and delivered the Bill of Sale and Assignment, in the form attached
hereto as Exhibit B, covering the Drilling Rigs, Equipment and Vehicles and
office equipment set forth on Annex 1 and the Drilling Contracts and Other
Agreements set forth on Annex 3.

(e) Warranty Deeds. ZIADRIL shall have executed and
delivered the respective Warranty Deeds covering the Real Property in the forms
attached hereto as Exhibits C(I) and C(II) relating to the West County Road
Property and the Marland Street Property, respectively.

(f) Title Insurance. PDC shall have obtained title
commitments for title insurance on the Real Property, the cost of which shall
be paid by PDC.

-9-
13
(g) Titles. ZIADRIL shall have endorsed and delivered
the title certificates to the motor vehicles described in Annex 1.

ARTICLE VI

GENERAL PROVISIONS

SECTION 6.1 Notices. All notices and other communications hereunder
shall be in writing and shall be deemed given if delivered personally, sent by
overnight courier or telecopied (with a confirmatory copy sent by overnight
courier) to the parties at the following addresses (or at such other address
for a party as shall be specified by like notice):

(a) if to PDC, to:

Patterson Energy, Inc.
4510 Lamesa Highway
P.O. Drawer 1416
Snyder, Texas 79550

Attention: A. Glenn Patterson
President and Chief Operating Officer

with copies to:

Thomas H. Maxfield, Esq.
Baker & Hostetler LLP
303 East 17th Avenue, Suite 1100
Denver, Colorado 80203-1264

(b) if to ZIADRIL, to:

Joe Smith, President
ZIADRIL, Inc.
P.O. Box 1860
Hobbs, New Mexico 88240

with copies to:

Tommy D. Parker, Esq.
206 West Snyder
Hobbs, New Mexico 88240

-10-
14
SECTION 6.2 Interpretation. When a reference is made in this
Agreement to a Section, such reference shall be to a Section of this Agreement
unless otherwise indicated, and the words "hereof', "herein" and "hereunder"
and similar terms refer to this Agreement as a whole and not to any particular
provision of this Agreement, unless the context otherwise requires. The table
of contents and headings contained in this Agreement are for reference purposes
only and shall not affect in any way the meaning or interpretation of this
Agreement. Whenever the words "include," "includes" or "including" are used in
this Agreement, they shall be deemed to be followed by the words "without
limitation."

SECTION 6.3 Counterparts. This Agreement may be executed in
counterparts, all of which shall be considered one and the same agreement and
shall become effective when one or more counterparts have been signed by each
of the parties and delivered to the other parties.

SECTION 6.4 Entire Agreement; No Third-Party Beneficiaries. This
Agreement, including the documents and instruments referred to herein, (i)
constitutes the entire agreement and supersedes all prior agreements and
understandings, both written and oral, among the parties with respect to the
subject matter hereof and (ii) is not intended to confer upon any person other
than the parties any rights or remedies hereunder; provided, however, that
legal counsel for ZIADRIL hereto may rely upon the representations and
warranties of ZIADRIL contained herein and in the certificates delivered
pursuant to Section 5.3(b).

SECTION 6.5 Governing Law. This Agreement shall be governed by, and
construed in accordance with, the laws of the State of New Mexico, regardless
of the laws that might otherwise govern under applicable principles of
conflicts of laws thereof.

SECTION 6.6 Assignment. Neither this Agreement nor any of the
rights, interests or obligations hereunder shall be assigned by any of the
parties without the prior written consent of the other parties. Subject to the
preceding sentence, this Agreement shall be binding upon, inure to the benefit
of, and be enforceable by, the parties and their respective successors and
assigns.

SECTION 6.7 Severability. If any term or other provision of this
Agreement is invalid, illegal or incapable of being enforced by any rule of
law, or public policy, all other conditions and provisions of this Agreement
shall nevertheless remain in full force and effect so long as the economic or
legal substance of the transactions contemplated hereby are not affected in any
manner materially adverse to any party. Upon such determination that any term
or other provision is invalid, illegal or incapable of being enforced, the
parties shall negotiate in good faith to modify this Agreement so as to effect
the original intent of the parties as closely as possible in a mutually
acceptable manner in order that the transactions be consummated as originally
contemplated to the fullest extent possible.

SECTION 6.8 Enforcement of This Agreement. The parties agree that
irreparable damage would occur in the event that any of the provisions of this
Agreement were not performed in accordance with their specific terms or were
otherwise breached. It is accordingly agreed that the parties shall be
entitled to an injunction or injunctions to prevent breaches of this Agreement
and to enforce specifically the terms and provisions hereof in any court of the
United States or any state

-11-
15
having jurisdiction, this being in addition to any other remedy to which they
are entitled at law or in equity.

IN WITNESS WHEREOF, PDC and ZIADRIL have executed this Agreement as of
the date first written above.

PDC:

PATTERSON DRILLING COMPANY

By: /s/ A. Glenn Patterson
-------------------------------------

A. Glenn Patterson
President and Chief Operating Officer

Attest:

/s/ James C. Brown
- ------------------------------------

James C. Brown, Secretary

ZIADRIL:

ZIADRIL, INC.

By: /s/ Joe Smith
-------------------------------------

Joe Smith
President
Attest:

/s/ Nancy A. Shelley
- ------------------------------------
Nancy A. Shelley, Secretary

TO INDUCE PATTERSON ENERGY, INC. TO ENTER INTO THIS ASSET PURCHASE
AGREEMENT AND FOR OTHER GOOD AND VALUABLE CONSIDERATION, THE RECEIPT AND
SUFFICIENCY OF WHICH ARE HEREBY ACKNOWLEDGED, THE UNDERSIGNED,

-12-
16
BEING OFFICERS, DIRECTORS, STOCKHOLDERS OF ZIADRIL, INC. IN THE CASE OF JOE
SMITH, KEN BROMLEY AND BILLY JENSEN, OR A CONSULTANT TO ZIADRIL, INC. IN THE
CASE OF LEE ROBERSON, ACCEPT AND AGREE TO BE BOUND BY THE INDEMNIFICATION
PROVISIONS OF SECTION 4.3 OF THE ABOVE ASSET PURCHASE AGREEMENT.

/s/ Joe Smith /s/ Billy Jensen
- ------------------------------------ ------------------------------------

Joe Smith Billy Jensen

/s/ Ken Bromley /s/ Lee Roberson
- ------------------------------------ ------------------------------------

Ken Bromley Lee Roberson

-13-
17
ANNEX 1
TO
ASSET PURCHASE AGREEMENT

DESCRIPTION OF DRILLING RIGS, EQUIPMENT
AND VEHICLES
PER WHEREAS CLAUSE

A. DRILLING RIGS AND EQUIPMENT.

RIG NO. DRAWWORKS MANUFACTURER
------- ----------------------

2 EMSCO GB-800
3 MID-CONTINENT V-712-A
6 SKYTOP BREWSTER N-75
7 BREWSTER N-75
10 MID CONTINENT V-36-A

All related yard equipment, including engines, mud pumps, derricks and
substructives, rotary tables, forklift, sand blaster, BOP shafter and
drill bits and all tubular goods on the rigs and in the yard.

NOTE: For more specific information concerning the rigs and related
equipment, see Appendix I, to Bill of Sale and Assignment attached to
this Agreement as Exhibit B.

B. VEHICLES.

All vehicles owned by ZIADRIL on March 31, 1997, consisting of 11
pickups and two trucks and trailers.

NOTE: For more specific information concerning the vehicles, see
Appendix I, to Bill of Sale and Assignment attached to this Agreement
as Exhibit B.

C. OFFICE EQUIPMENT.

All office equipment owned by ZIADRIL.
18
ANNEX 2
TO
ASSET PURCHASE AGREEMENT

DESCRIPTION OF REAL PROPERTY
PER WHEREAS CLAUSE

1. Building, shop and yard owned by ZIADRIL at 901 West Marland,
Hobbs, New Mexico, including all improvements.

2. The yard owned by ZIADRIL on West County Road, Hobbs, New
Mexico, including all improvements.

NOTE: The Real Property is more particularly described on the
respective General Warranty Deeds attached to this Agreement as Exhibits C(I)
and C(II).
19
ANNEX 3
TO
ASSET PURCHASE AGREEMENT

LIST OF DRILLING CONTRACTS AND OTHER
AGREEMENTS PER SECTION 3.5

A. DRILLING CONTRACTS.

1. Drilling Contract dated March 12, 1997, between Penwell
Energy, Inc. and ZIADRIL, Inc.

2. Drilling Contract dated March 25, 1997, between Chesapeake
Operating, Inc. and ZIADRIL, Inc.

3. Drilling Contract dated March 26, 1997, between Penwell
Energy, Inc. and ZIADRIL, Inc.

4. Drilling Contract dated February 24, 1997, between John L. Fox
and ZIADRIL, Inc.

5. Drilling Contract dated February 28, 1997, between Amerlind
Oil Company, Ltd. and ZIADRIL, Inc.

B. OTHER AGREEMENTS.

1. Lease Agreement dated August 1, 1990, between ZIADRIL, Inc. as
lessor, and Wilson Industries, Inc. as lessee.

2. Commercial Lease and Deposit Receipt dated August 23, 1995,
from Bo Blackwood, agent for Crystal Clear Water Sales and
Services to ZIADRIL, Inc.

3. 1st Equity Realtors, Inc. Property Leasing Agreement dated
August 25, 1995, between ZIADRIL, Inc. and First Equity
Realtors, Inc.
20
ANNEX 4
TO
ASSET PURCHASE AGREEMENT

LIST OF ZIADRIL STOCKHOLDERS
PER SECTION 3.9

ZIADRIL, INC. SHAREHOLDERS

NUMBER OF
NAME SHARES PERCENTAGE
- --------------------------------------------------------------------------------

Randy Allison . . . . . . . . . . . . . . . 122.73 0.001185

Ricky Alavardo . . . . . . . . . . . . . . 130.38 0.001259

Jackie Brantner . . . . . . . . . . . . . . 115.66 0.001116

Ken Bromley . . . . . . . . . . . . . . . . 10,934.89 0.105550

James Bullock . . . . . . . . . . . . . . . 8,213.34 0.079280

Latricia Quiroz . . . . . . . . . . . . . . 2,849.06 0.027501

Ronald Campbell . . . . . . . . . . . . . . 75.84 0.000732

Danny Compton . . . . . . . . . . . . . . . 190.94 0.001843

Richard Cortez . . . . . . . . . . . . . . 3.60 0.000035

Carlos Davila . . . . . . . . . . . . . . . 81.78 0.000789

Eric Davis . . . . . . . . . . . . . . . . 57.04 0.000551

Larry Fagan . . . . . . . . . . . . . . . . 234.80 0.002266

Joe Fixel . . . . . . . . . . . . . . . . . 296.20 0.002859

Jason Flowers . . . . . . . . . . . . . . . 50.13 0.000484

Samuel Freeman . . . . . . . . . . . . . . 56.44 0.000545

Paul Garner . . . . . . . . . . . . . . . . 59.33 0.000573

Tom Gilcrease . . . . . . . . . . . . . . . 1,272.65 0.012284

Kenneth Goldsmith . . . . . . . . . . . . . 429.80 0.004149

Melva Graham . . . . . . . . . . . . . . . 488.74 0.004718

Kirby Gray . . . . . . . . . . . . . . . . 97.97 0.000946

Kevin Griffin . . . . . . . . . . . . . . . 324.29 0.003130

Louis Grossman . . . . . . . . . . . . . . 333.39 0.003218

AX-1
21

NUMBER OF
NAME SHARES PERCENTAGE
- --------------------------------------------------------------------------------

George Herd . . . . . . . . . . . . . . . . 80.30 0.000775

Eloy Heredia . . . . . . . . . . . . . . . 1,570.18 0.015156

Scott Holm . . . . . . . . . . . . . . . . 108.84 0.001051

Joe Janica . . . . . . . . . . . . . . . . 100.00 0.000965

Billy Jensen . . . . . . . . . . . . . . . 9,022.63 0.087092

Keith Jernigan . . . . . . . . . . . . . . 2,263.30 0.021847

Douglas Keen . . . . . . . . . . . . . . . 64.45 0.000622

Paul Landrum . . . . . . . . . . . . . . . 135.76 0.001310

Roger Larmon . . . . . . . . . . . . . . . 111.92 0.001080

Russell Loven . . . . . . . . . . . . . . . 6,213.26 0.059974

Michael Malone . . . . . . . . . . . . . . 1,296.27 0.012512

Teddy Martin . . . . . . . . . . . . . . . 2.50 0.000024

Issicc Miller . . . . . . . . . . . . . . . 46.40 0.000448

Carl Morley . . . . . . . . . . . . . . . . 36.02 0.000348

Robert Northcutt . . . . . . . . . . . . . 732.01 0.007066

Charles Noseff . . . . . . . . . . . . . . 4,908.32 0.047378

Paul Noseff . . . . . . . . . . . . . . . . 68.37 0.000660

Shirrel Noseff . . . . . . . . . . . . . . 14,369.91 0.138708

Carroll Oldaker . . . . . . . . . . . . . . 516.03 0.004981

Roger Oldaker . . . . . . . . . . . . . . . 408.32 0.003941

Howard Perkins . . . . . . . . . . . . . . 3.52 0.000034

Virginia Perry . . . . . . . . . . . . . . 1,509.60 0.014572

James R. Rippy . . . . . . . . . . . . . . 2,403.59 0.023201

David Rodriquez . . . . . . . . . . . . . . 145.78 0.001407

Pete Rodriquez . . . . . . . . . . . . . . 53.43 0.000516

Larry Romero . . . . . . . . . . . . . . . 242.62 0.002342

James Scarborough . . . . . . . . . . . . . 74.08 0.000715

Joe Scott . . . . . . . . . . . . . . . . . 88.11 0.000850

Michael Sharp . . . . . . . . . . . . . . . 200.70 0.001937

Nancy Shelley . . . . . . . . . . . . . . . 15,856.41 0.153056

Howard Smith . . . . . . . . . . . . . . . 105.03 0.001014

AX-2
22

NUMBER OF
NAME SHARES PERCENTAGE
- --------------------------------------------------------------------------------

Joe Smith . . . . . . . . . . . . . . . . . 10,931.78 0.105520

Judy Streun . . . . . . . . . . . . . . . . 30.16 0.000291

Bradley Tate . . . . . . . . . . . . . . . 49.58 0.000479

Clifford Thomas . . . . . . . . . . . . . . 68.23 0.000659

Chris Van Dorren . . . . . . . . . . . . . 911.48 0.008798

Charles Wegner, Jr. . . . . . . . . . . . . 56.70 0.000547

Delmar Ray White . . . . . . . . . . . . . 2,388.92 0.023059

Richard Woodall . . . . . . . . . . . . . . 5.17 0.000050
---------- --------

TOTALS 103,598.66 1.00
========== ========

AX-3
23
EXHIBIT A(I)

PATTERSON DRILLING COMPANY

NON-COMPETITION AGREEMENT

THIS NON-COMPETITION AGREEMENT is made and entered into this
_____ day of April, 1997 (this "Agreement"), by and between PATTERSON DRILLING
COMPANY, a Delaware corporation ("PDC"), and ZIADRIL, INC., a New Mexico
corporation ("ZIADRIL").

RECITALS:

A. Simultaneously with the execution of this Agreement,
PDC and ZIADRIL have entered into that certain Asset Purchase Agreement, dated
of even date herewith (the "Asset Purchase Agreement"), providing for, among
other things, the purchase by PDC of the drilling rigs, related equipment,
rolling stock, office equipment and real property owned by ZIADRIL.

B. The execution and delivery of this Agreement is a
condition to the consummation of the Asset Purchase contemplated by the Asset
Purchase Agreement, and the parties are entering into this Agreement in order
to fulfill such condition.

NOW, THEREFORE, in consideration of the foregoing, the mutual
covenants and agreements contained herein, and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
the parties, intending to be legally bound, hereby agree as follows:

1. Period of Agreement.

The period of this Agreement shall commence on the date hereof
and remain in effect through May 1, 2002.

2. Covenant Not to Compete.

(a) ZIADRIL covenants and agrees that during the
Non-Compete Period, ZIADRIL shall not, without the prior written consent of
PDC, directly or indirectly, alone or in association with any other person,
carry on, be engaged, concerned, or take part in, render services to, or own,
share in the earnings of, or invest in the stock, bonds, or other securities
of, any person which is engaged in, the contract oil and gas well drilling
business within the Permian Basin of West Texas and Southeastern New Mexico
(the "Competitive Business"); provided, however, that ZIADRIL may invest in
stock, bonds, or other securities of any Competitive Business (but without
otherwise participating in the Competitive Business) if: (A) such stock,
bonds, or other securities are listed on any national securities exchange or
are registered under Section 12(g) of the Securities Exchange Act of 1934, as
amended; (B) the investment does not exceed, in the case of any class of
capital stock

Exh A(I) - 1
24
of any one issuer, two percent (2%) of the issued and outstanding shares, or,
in the case of bonds or other securities of any one issuer, two percent (2%) of
the aggregate principal amount thereof issued and outstanding; and (C) such
investment would not prevent, directly or indirectly, the transaction of
business by PDC or any affiliate of PDC with any state, district, territory, or
possession of the United States or any governmental subdivision, agency, or
instrumentality thereof by virtue of any statute, law, regulation or
administrative practice. The period of time during which ZIADRIL is prohibited
from engaging in certain activities by this Section shall be extended by the
length of time during which ZIADRIL is in breach of the terms of this section.

(b) It is understood by and between the parties hereto
that the foregoing covenant by ZIADRIL not to enter into competition with PDC
as set forth in Section 2(a) hereof is an essential element of this Agreement
and the Asset Purchase Agreement and that, but for the agreement of ZIADRIL to
comply with such covenant, PDC would not have agreed to enter into this
Agreement or the Asset Purchase Agreement. PDC and ZIADRIL have independently
consulted with their respective counsel and have been advised in all respects
concerning the reasonableness and propriety of such covenant, with specific
regard to the nature of the business conducted by PDC and its affiliates.
ZIADRIL agrees that such covenant is reasonable in scope, geographic area, and
duration, and that compliance with such covenant would not impose economic
hardship on ZIADRIL.

3. Restrictions on Soliciting Business of PDC.

ZIADRIL further covenants and agrees that during the
Non-Compete Period, ZIADRIL will not, either for itself or for any other person
or entity, directly or indirectly, engage in any of the following activities in
a Competitive Business without the express prior written consent of PDC:

(a) Solicit or hire any of the employees of PDC or
solicit or take away any of PDC's customers, lessors, or suppliers or attempt
any of the foregoing:

(b) Acquire or attempt to acquire rights providing any
product or service in a Competitive Business within the territory described in
Section 2 hereof; or

(c) Engage in any act which would interfere with or harm
any business relationship PDC has with any customer, lessor, employee,
principal or supplier.

4. Specific Performance.

Without intending to limit the remedies available to PDC,
ZIADRIL acknowledges that PDC will have no adequate remedies at law if ZIADRIL
violates the terms of Section 3 or 4, hereof. In such event, ZIADRIL agrees
that PDC shall have the right, in addition to any other rights it may have, to
obtain in any court of competent jurisdiction specific performance of such
Sections of this Agreement or injunctive relief to restrain any breach or
threatened breach thereof. Nothing herein shall be construed as prohibiting
PDC from pursuing any other remedies available to PDC (whether at law or in
equity) for such breach or threatened breach, including, without limitation,
the recovery of monetary damages from ZIADRIL.

Exh A(I) - 2
25
The provisions of this Section 4 shall survive the expiration,
termination or cancellation of this Agreement.

5. Attorneys Fees and Costs.

If an action at law or in equity is necessary to enforce or
interpret the terms of this Agreement, the prevailing party shall be entitled
to reasonable attorneys fees, costs and necessary expenses in addition to any
other relief to which that party may be entitled. This provision is applicable
to this entire Agreement.

6. Representations and Warranties of PDC and ZIADRIL.

(a) Representations and Warranties of PDC. PDC hereby
represents and warrants to ZIADRIL that: (i) it has all requisite power to
enter into and perform its obligations under this Agreement; (ii) this
Agreement has been duly and validly authorized by all necessary corporate
action on the part of PDC; (iii) the execution of this Agreement by PDC and
performance of PDC's obligations hereunder do not require the consent or
approval of any other party; and (iv) this Agreement is a valid and binding
obligation of PDC.

(b) Representations and Warranties of ZIADRIL. ZIADRIL
hereby represents and warrants to PDC that: (i) ZIADRIL has the capacity and
power to enter into and perform obligations of ZIADRIL under this Agreement;
(ii) ZIADRIL has duly and validly executed this Agreement; (iii) the execution
of this Agreement and performance of obligations of ZIADRIL hereunder do not
require the consent or approval of any other party; and (iv) this Agreement
constitutes a valid and binding obligation of ZIADRIL.

7. General Provisions.

(a) Compliance with Laws. The parties agree that they
will comply with all applicable laws and regulations of government bodies or
agencies in their respective performance of their obligations under this
Agreement.

(b) Governing Law and Construction. This Agreement will
be governed by and construed in accordance with the laws of the State of New
Mexico without reference to its conflict-of-laws principles. This Agreement's
final form resulted from review and negotiations among the parties and their
attorneys, and no part of this Agreement should be construed against any party
on the basis of authorship.

(c) Forum for Dispute Resolution. If any dispute arises
among the parties concerning the interpretation or performance of any portion
of this Agreement which the parties are unable to resolve themselves, and any
party brings an action against any other party seeking a declaratory order,
specific performance, damages, or any other legal or equitable relief based on
this Agreement, the parties agree that the forum for any such action shall be
an appropriate federal or state court in New Mexico having jurisdiction, agree
that venue will be proper in such courts, and waive any objections based on
inconvenience of the forum, and further agree that the prevailing party

Exh A(I) - 3
26
in any such action, as determined by the court, shall be awarded its reasonable
attorneys' fees and costs in addition to any relief or judgment the court
awards.

(d) Entire Agreement; Amendment. This Agreement
constitutes the entire agreement between the parties with respect to the
subject matter contained herein and supersedes any previous oral or written
communications, representations, understandings or agreements with respect
thereto. The terms of this Agreement may be modified only in a writing, signed
by authorized representatives of both parties.

(e) Assignability. This Agreement will be binding upon
the parties' respective successors and permitted assigns. Neither party may
assign this Agreement and/or any of its rights and/or obligations hereunder
without the prior written consent of the other party, and any such attempted
assignment will be void; provided, however, that PDC may assign this Agreement
to a subsidiary or affiliate without the prior written consent of ZIADRIL, and
provided further that a transfer by PDC as a result of a merger or sale of all
or substantially all of the assets of PDC with or to a third party that assumes
PDC's obligations hereunder by operation of law or otherwise shall not
constitute a prohibited assignment under this Section 8(e).

(f) Waiver. A waiver of a breach or default under this
Agreement will not constitute a waiver of any other breach or default. Failure
or delay by either party to enforce compliance with any term or condition of
this Agreement will not constitute a waiver of such term or condition.

(g) Severability. If any provision of this Agreement is
declared to be invalid, the parties agree that such invalidity will not affect
the validity of the remaining provisions of this Agreement, and further agree,
to the extent possible, to substitute for the invalid provision a valid
provision that approximates the intent and economic effect of the invalid
provision as closely as possible.

(h) Headings. The titles of the Sections and subsections
of this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

(i) Notice. Any notice, request, consent, demand or
other communication required to be given under this Agreement will be in
writing and will be given personally, by facsimile or by mailing the same,
first-class, postage prepaid to the appropriate address and facsimile number
set forth below or to such other person or at such other address as may
hereafter be designated by like notice. Notices by mail will be considered
delivered and become effective three days after the mailing thereof. All
notices by facsimile will be considered delivered and become effective
immediately upon the confirmed (by answer back or other tangible printed
verification or successful receipt) sending thereof.

Exh A(I) - 4
27
To PDC:
Patterson Drilling Company
4510 Lamesa Highway
P.O. Drawer 1410
Snyder, Texas 79550
Facsimile: (915) 573-0281
Attention: A. Glenn Patterson
President and Chief Operating
Officer

To ZIADRIL:
ZIADRIL, Inc.
P.O. Box 1860
Hobbs, New Mexico 88240

with copies to:
Tommy D. Parker, Esq.
206 West Snyder
Hobbs, New Mexico 88740

(j) Counterparts. This Agreement may be executed in
counterparts and by the parties hereto in separate counterparts, each of which
will be deemed an original, but all of which together will constitute one and
the same instrument.

IN WITNESS WHEREOF, the undersigned have caused this Agreement
to be executed by their respective representatives as of the day and year first
above written.

"PDC"

PATTERSON DRILLING COMPANY

By:
------------------------------------
A. Glenn Patterson
President

"ZIADRIL"

ZIADRIL, INC.

By:
-------------------------------------
Joe Smith
President

Exh A(I) - 5
28
EXHIBIT A(II)

PATTERSON DRILLING COMPANY

NON-COMPETITION AGREEMENT

THIS NON-COMPETITION AGREEMENT is made and entered into this
_____ day of April, 1997 (this "Agreement"), by and between PATTERSON DRILLING
COMPANY, a Delaware corporation ("PDC"), and JOE SMITH, an individual residing
in Hobbs, New Mexico ("J Smith").

RECITALS:

C. Simultaneously with the execution of this Agreement,
PDC has entered into that certain Asset Purchase Agreement, dated of even date
herewith (the "Asset Purchase Agreement"), between PDC and ZIADRIL, Inc.
("ZIADRIL"), providing for, among other things, the purchase by PDC of the
drilling rigs, related equipment, rolling stock and office equipment owned by
ZIADRIL.

D. J Smith is an officer, a director and a stockholder
of ZIADRIL.

E. The execution and delivery of this Agreement is a
condition to the consummation of the Asset Purchase contemplated by the Asset
Purchase Agreement, and the parties are entering into this Agreement in order
to fulfill such condition.

1. Period of Agreement.

The period of this Agreement shall commence on the date hereof
and remain in effect through May 1, 2002, unless sooner terminated as the
result of the death of J Smith (the "Non-Compete Period").

2. Compensation.

Simultaneously with the execution of this Agreement, PDC has
paid J Smith, by cashier's check, the amount of $675,000 as compensation for
entering into this Agreement.

Exh A(II)-1
29
3. Covenant Not to Compete.

(a) J Smith covenants and agrees that during the
Non-Compete Period, J Smith shall not, without the prior written consent of
PDC, directly or indirectly, and whether as a principal or as an agent,
officer, director, employee, consultant, or otherwise, alone or in association
with any other person, carry on, be engaged, concerned, or take part in, render
services to, or own, share in the earnings of, or invest in the stock, bonds,
or other securities of, any person which is engaged in, the contract oil and
gas well drilling business within the Permian Basin of West Texas and
Southeastern New Mexico (the "Competitive Business"); provided, however, that J
Smith may invest in stock, bonds, or other securities of any Competitive
Business (but without otherwise participating in the Competitive Business) if:
(A) such stock, bonds, or other securities are listed on any national
securities exchange or are registered under Section 12(g) of the Securities
Exchange Act of 1934, as amended; (B) the investment does not exceed, in the
case of any class of capital stock of any one issuer, two percent (2%) of the
issued and outstanding shares, or, in the case of bonds or other securities of
any one issuer, two percent (2%) of the aggregate principal amount thereof
issued and outstanding; and (C) such investment would not prevent, directly or
indirectly, the transaction of business by PDC or any affiliate of PDC with any
state, district, territory, or possession of the United States or any
governmental subdivision, agency, or instrumentality thereof by virtue of any
statute, law, regulation or administrative practice. The period of time during
which J Smith is prohibited from engaging in certain activities by this Section
shall be extended by the length of time during which J Smith is in breach of
the terms of this section.

(b) It is understood by and between the parties hereto
that the foregoing covenant by J Smith not to enter into competition with PDC
as set forth in Section 3(a) hereof is an essential element of this Agreement
and the Asset Purchase Agreement and that, but for the agreement of J Smith to
comply with such covenant, PDC would not have agreed to enter into this
Agreement or the Asset Purchase Agreement. PDC and J Smith have independently
consulted with their respective counsel and have been advised in all respects
concerning the reasonableness and propriety of such covenant, with specific
regard to the nature of the business conducted by PDC and its affiliates. J
Smith agrees that such covenant is reasonable in scope, geographic area, and
duration, and that compliance with such covenant would not impose economic or
professional hardship on J Smith.

4. Restrictions on Soliciting Business of PDC.

J Smith further covenants and agrees that during the
Non-Compete Period, J Smith will not, either for himself or for any other
person or entity, directly or indirectly, engage in any of the following
activities in a Competitive Business without the express prior written consent
of PDC:

(a) Solicit or hire any of the employees of PDC or
solicit or take away any of PDC's customers, lessors, or suppliers or attempt
any of the foregoing:

(b) Acquire or attempt to acquire rights providing any
product or service in a Competitive Business within the territory described in
Section 3 hereof; or

Exh A(II)-2
30
(c) Engage in any act which would interfere with or harm
any business relationship PDC has with any customer, lessor, employee,
principal or supplier.

5. Specific Performance.

Without intending to limit the remedies available to PDC, J
Smith acknowledges that PDC will have no adequate remedies at law if J Smith
violates the terms of Section 3 or 4, hereof. In such event, J Smith agrees
that PDC shall have the right, in addition to any other rights it may have, to
obtain in any court of competent jurisdiction specific performance of such
Sections of this Agreement or injunctive relief to restrain any breach or
threatened breach thereof. Nothing herein shall be construed as prohibiting
PDC from pursuing any other remedies available to PDC (whether at law or in
equity) for such breach or threatened breach, including, without limitation,
the recovery of monetary damages from J Smith.

The provisions of this Section 5 shall survive the expiration,
termination or cancellation of this Agreement.

6. Attorneys Fees and Costs.

7. Representations and Warranties of PDC and J Smith.

(a) Representations and Warranties of PDC. PDC hereby
represents and warrants to J Smith that: (i) it has all requisite power to
enter into and perform its obligations under this Agreement; (ii) this
Agreement has been duly and validly authorized by all necessary corporate
action on the part of PDC; (iii) the execution of this Agreement by PDC and
performance of PDC's obligations hereunder do not require the consent or
approval of any other party; and (iv) this Agreement is a valid and binding
obligation of PDC.

(b) Representations and Warranties of J Smith. J Smith
hereby represents and warrants to PDC that: (i) J Smith has the capacity and
power to enter into and perform obligations of J Smith under this Agreement;
(ii) J Smith has duly and validly executed this Agreement; (iii) the execution
of this Agreement and performance of obligations of J Smith hereunder do not
require the consent or approval of any other party; and (iv) this Agreement
constitutes a valid and binding obligation of J Smith.

8. General Provisions.

Exh A(II)-3
31
(b) Governing Law and Construction. This Agreement will
be governed by and construed in accordance with the laws of the State of New
Mexico without reference to its conflict-of-laws principles. This Agreement's
final form resulted from review and negotiations among the parties and their
attorneys, and no part of this Agreement should be construed against any party
on the basis of authorship.

(e) Assignability. This Agreement will be binding upon
the parties' respective successors and permitted assigns. Neither party may
assign this Agreement and/or any of its rights and/or obligations hereunder
without the prior written consent of the other party, and any such attempted
assignment will be void; provided, however, that PDC may assign this Agreement
to a subsidiary or affiliate without the prior written consent of J Smith, and
provided further that a transfer by PDC as a result of a merger or sale of all
or substantially all of the assets of PDC with or to a third party that assumes
PDC's obligations hereunder by operation of law or otherwise shall not
constitute a prohibited assignment under this Section 8(e).

(h) Headings. The titles of the Sections and subsections
of this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

Exh A(II)-4
32
(i) Notice. Any notice, request, consent, demand or
other communication required to be given under this Agreement will be in
writing and will be given personally, by facsimile or by mailing the same,
first-class, postage prepaid to the appropriate address and facsimile number
set forth below or to such other person or at such other address as may
hereafter be designated by like notice. Notices by mail will be considered
delivered and become effective three days after the mailing thereof. All
notices by facsimile will be considered delivered and become effective
immediately upon the confirmed (by answer back or other tangible printed
verification or successful receipt) sending thereof.

To PDC:

Patterson Drilling Company
4510 Lamesa Highway
P.O. Drawer 1410
Snyder, Texas 79550
Facsimile: (915) 573-0281
Attention: A. Glenn Patterson
President and Chief Operating
Officer

To J Smith:

Joe Smith
1116 Jicarilla
Hobbs, New Mexico 88240

with copies to:

Tommy D. Parker, Esq.
206 West Snyder
Hobbs, New Mexico 88240

Exh A(II)-5
33
IN WITNESS WHEREOF, the undersigned have caused this Agreement
to be executed by their respective representatives as of the day and year first
above written.

"PDC"

PATTERSON DRILLING COMPANY

By:
-------------------------------------
A. Glenn Patterson
President

"J SMITH"

----------------------------------------
Joe Smith

Exh A(II)-6
34
EXHIBIT A(III)

PATTERSON DRILLING COMPANY

NON-COMPETITION AGREEMENT

THIS NON-COMPETITION AGREEMENT is made and entered into this
_____ day of April, 1997 (this "Agreement"), by and between PATTERSON DRILLING
COMPANY, a Delaware corporation ("PDC"), and KEN BROMLEY, an individual
residing in Hobbs, New Mexico ("K Bromley").

RECITALS:

F. Simultaneously with the execution of this Agreement,
PDC has entered into that certain Asset Purchase Agreement, dated of even date
herewith (the "Asset Purchase Agreement"), between PDC and ZIADRIL, Inc.
("ZIADRIL"), providing for, among other things, the purchase by PDC of the
drilling rigs, related equipment, rolling stock and office equipment owned by
ZIADRIL.

G. Ken Bromley is an officer, a director and a
stockholder of ZIADRIL.

H. The execution and delivery of this Agreement is a
condition to the consummation of the Asset Purchase contemplated by the Asset
Purchase Agreement, and the parties are entering into this Agreement in order
to fulfill such condition.

1. Period of Agreement.

The period of this Agreement shall commence on the date hereof
and remain in effect through May 1, 2002, unless sooner terminated as the
result of the death of K Bromley (the "Non-Compete Period").

2. Compensation.

Simultaneously with the execution of this Agreement, PDC has
paid K Bromley, by cashier's check, the amount of $675,000 as compensation for
entering into this Agreement.

Exh A(III)-1
35
3. Covenant Not to Compete.

(a) K Bromley covenants and agrees that during the
Non-Compete Period, K Bromley shall not, without the prior written consent of
PDC, directly or indirectly, and whether as a principal or as an agent,
officer, director, employee, consultant, or otherwise, alone or in association
with any other person, carry on, be engaged, concerned, or take part in, render
services to, or own, share in the earnings of, or invest in the stock, bonds,
or other securities of, any person which is engaged in, the contract oil and
gas well drilling business within the Permian Basin of West Texas and
Southeastern New Mexico (the "Competitive Business"); provided, however, that K
Bromley may invest in stock, bonds, or other securities of any Competitive
Business (but without otherwise participating in the Competitive Business) if:
(A) such stock, bonds, or other securities are listed on any national
securities exchange or are registered under Section 12(g) of the Securities
Exchange Act of 1934, as amended; (B) the investment does not exceed, in the
case of any class of capital stock of any one issuer, two percent (2%) of the
issued and outstanding shares, or, in the case of bonds or other securities of
any one issuer, two percent (2%) of the aggregate principal amount thereof
issued and outstanding; and (C) such investment would not prevent, directly or
indirectly, the transaction of business by PDC or any affiliate of PDC with any
state, district, territory, or possession of the United States or any
governmental subdivision, agency, or instrumentality thereof by virtue of any
statute, law, regulation or administrative practice. The period of time during
which K Bromley is prohibited from engaging in certain activities by this
Section shall be extended by the length of time during which K Bromley is in
breach of the terms of this section.

(b) It is understood by and between the parties hereto
that the foregoing covenant by K Bromley not to enter into competition with PDC
as set forth in Section 3(a) hereof is an essential element of this Agreement
and the Asset Purchase Agreement and that, but for the agreement of K Bromley
to comply with such covenant, PDC would not have agreed to enter into this
Agreement or the Asset Purchase Agreement. PDC and K Bromley have
independently consulted with their respective counsel and have been advised in
all respects concerning the reasonableness and propriety of such covenant, with
specific regard to the nature of the business conducted by PDC and its
affiliates. K Bromley agrees that such covenant is reasonable in scope,
geographic area, and duration, and that compliance with such covenant would not
impose economic or professional hardship on K Bromley.

4. Restrictions on Soliciting Business of PDC.

K Bromley further covenants and agrees that during the
Non-Compete Period, K Bromley will not, either for himself or for any other
person or entity, directly or indirectly, engage in any of the following
activities in a Competitive Business without the express prior written consent
of PDC:

(a) Solicit or hire any of the employees of PDC or
solicit or take away any of PDC's customers, lessors, or suppliers or attempt
any of the foregoing:

(b) Acquire or attempt to acquire rights providing any
product or service in a Competitive Business within the territory described in
Section 3 hereof; or

Exh A(III)-2
36
(c) Engage in any act which would interfere with or harm
any business relationship PDC has with any customer, lessor, employee,
principal or supplier.

5. Specific Performance.

Without intending to limit the remedies available to PDC, K
Bromley acknowledges that PDC will have no adequate remedies at law if K
Bromley violates the terms of Section 3 or 4, hereof. In such event, K Bromley
agrees that PDC shall have the right, in addition to any other rights it may
have, to obtain in any court of competent jurisdiction specific performance of
such Sections of this Agreement or injunctive relief to restrain any breach or
threatened breach thereof. Nothing herein shall be construed as prohibiting
PDC from pursuing any other remedies available to PDC (whether at law or in
equity) for such breach or threatened breach, including, without limitation,
the recovery of monetary damages from K Bromley.

The provisions of this Section 5 shall survive the expiration,
termination or cancellation of this Agreement.

6. Attorneys Fees and Costs.

7. Representations and Warranties of PDC and K Bromley.

(a) Representations and Warranties of PDC. PDC hereby
represents and warrants to K Bromley that: (i) it has all requisite power to
enter into and perform its obligations under this Agreement; (ii) this
Agreement has been duly and validly authorized by all necessary corporate
action on the part of PDC; (iii) the execution of this Agreement by PDC and
performance of PDC's obligations hereunder do not require the consent or
approval of any other party; and (iv) this Agreement is a valid and binding
obligation of PDC.

(b) Representations and Warranties of K Bromley. K
Bromley hereby represents and warrants to PDC that: (i) K Bromley has the
capacity and power to enter into and perform obligations of K Bromley under
this Agreement; (ii) K Bromley has duly and validly executed this Agreement;
(iii) the execution of this Agreement and performance of obligations of K
Bromley hereunder do not require the consent or approval of any other party;
and (iv) this Agreement constitutes a valid and binding obligation of K
Bromley.

8. General Provisions.

Exh A(III)-3
37
(b) Governing Law and Construction. This Agreement will
be governed by and construed in accordance with the laws of the State of New
Mexico without reference to its conflict-of-laws principles. This Agreement's
final form resulted from review and negotiations among the parties and their
attorneys, and no part of this Agreement should be construed against any party
on the basis of authorship.

(e) Assignability. This Agreement will be binding upon
the parties' respective successors and permitted assigns. Neither party may
assign this Agreement and/or any of its rights and/or obligations hereunder
without the prior written consent of the other party, and any such attempted
assignment will be void; provided, however, that PDC may assign this Agreement
to a subsidiary or affiliate without the prior written consent of K Bromley,
and provided further that a transfer by PDC as a result of a merger or sale of
all or substantially all of the assets of PDC with or to a third party that
assumes PDC's obligations hereunder by operation of law or otherwise shall not
constitute a prohibited assignment under this Section 8(e).

(h) Headings. The titles of the Sections and subsections
of this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

Exh A(III)-4
38
(i) Notice. Any notice, request, consent, demand or
other communication required to be given under this Agreement will be in
writing and will be given personally, by facsimile or by mailing the same,
first-class, postage prepaid to the appropriate address and facsimile number
set forth below or to such other person or at such other address as may
hereafter be designated by like notice. Notices by mail will be considered
delivered and become effective three days after the mailing thereof. All
notices by facsimile will be considered delivered and become effective
immediately upon the confirmed (by answer back or other tangible printed
verification or successful receipt) sending thereof.

To PDC:

Patterson Drilling Company
4510 Lamesa Highway
P.O. Drawer 1410
Snyder, Texas 79550
Facsimile: (915) 573-0281
Attention: A. Glenn Patterson
President and Chief Operating
Officer

To K Bromley:

Ken Bromley
1318 Paige
Hobbs, New Mexico 88240

with copies to:

Tommy D. Parker, Esq.
206 West Snyder
Hobbs, New Mexico 88240

Exh A(III)-5
39
IN WITNESS WHEREOF, the undersigned have caused this Agreement
to be executed by their respective representatives as of the day and year first
above written.

"PDC"

PATTERSON DRILLING COMPANY

By:
-------------------------------------
A. Glenn Patterson
President

"K Bromley"

----------------------------------------
Ken Bromley

Exh A(III)-6
40
EXHIBIT A(IV)

PATTERSON DRILLING COMPANY

NON-COMPETITION AGREEMENT

THIS NON-COMPETITION AGREEMENT is made and entered into this
_____ day of April, 1997 (this "Agreement"), by and between PATTERSON DRILLING
COMPANY, a Delaware corporation ("PDC"), and BILLY JENSEN, an individual
residing in Hobbs, New Mexico ("B Jensen").

RECITALS:

I. Simultaneously with the execution of this Agreement,
PDC has entered into that certain Asset Purchase Agreement, dated of even date
herewith (the "Asset Purchase Agreement"), between PDC and ZIADRIL, Inc.
("ZIADRIL"), providing for, among other things, the purchase by PDC of the
drilling rigs, related equipment, rolling stock, office equipment and real
property owned by ZIADRIL.

J. Billy Jensen is an officer, a director and a
stockholder of ZIADRIL.

K. The execution and delivery of this Agreement is a
condition to the consummation of the Asset Purchase contemplated by the Asset
Purchase Agreement, and the parties are entering into this Agreement in order
to fulfill such condition.

1. Period of Agreement.

Unless sooner terminated as the result of the death of B
Jensen, the period of this Agreement shall commence on the date hereof and
remain in effect during the period of B Jensen's employment by PDC and shall
end on the first to occur of the following (the "Non-Compete Period"): (i) one
year following termination by PDC of B Jensen's employment if such termination
is without Cause (as defined below); (ii) three years following termination by
PDC of B Jensen's employment if such employment is for Cause (as defined
below); or (iii) three years following the date of termination by B Jensen of
his employment with PDC for any reason.

For purposes of this Agreement, termination for "Cause" means
termination because of:

A(IV)-1
41
(a) The continued failure by B Jensen to substantially
perform or the gross negligence in the performance of his duties hereunder
after PDC has made a written demand for performance which specifically
identifies the manner in which it believed that B Jensen has not substantially
performed his duties.

(b) The commission by B Jensen of a willful act of
dishonesty or misconduct which is injurious to PDC or Patterson Energy, Inc.
("PEC") or any other subsidiary of PEC., or the breach of a fiduciary duty to
PDC or PEC.

(c) A conviction or a plea of guilty or nolo contendere
in connection with fraud or any crime that constitutes a felony in the
jurisdiction involved not subject to further appeal or review, if such
conviction or plea is injurious to PDC or PEC.

(d) The commission by B Jensen of repeated acts of
substance abuse which are injurious to PDC or PEC.

2. Compensation.

Simultaneously with the execution of this Agreement, PDC has
paid B Jensen, by cashier's check, the amount of $200,000 as compensation for
entering into this Agreement.

3. Covenant Not to Compete.

(a) B Jensen covenants and agrees that during the
Non-Compete Period, B Jensen shall not, without the prior written consent of
PDC, directly or indirectly, and whether as a principal or as an agent,
officer, director, employee, consultant, or otherwise, alone or in association
with any other person, carry on, be engaged, concerned, or take part in, render
services to, or own, share in the earnings of, or invest in the stock, bonds,
or other securities of, any person which is engaged in, the contract oil and
gas well drilling business within the Permian Basin of West Texas and
Southeastern New Mexico (the "Competitive Business"); provided, however, that B
Jensen may invest in stock, bonds, or other securities of any Competitive
Business (but without otherwise participating in the Competitive Business) if:
(A) such stock, bonds, or other securities are listed on any national
securities exchange or are registered under Section 12(g) of the Securities
Exchange Act of 1934, as amended; (B) the investment does not exceed, in the
case of any class of capital stock of any one issuer, two percent (2%) of the
issued and outstanding shares, or, in the case of bonds or other securities of
any one issuer, two percent (2%) of the aggregate principal amount thereof
issued and outstanding; and (C) such investment would not prevent, directly or
indirectly, the transaction of business by PDC or any affiliate of PDC with any
state, district, territory, or possession of the United States or any
governmental subdivision, agency, or instrumentality thereof by virtue of any
statute, law, regulation or administrative practice. The period of time during
which B Jensen is prohibited from engaging in certain activities by this
Section shall be extended by the length of time during which B Jensen is in
breach of the terms of this section.

(b) It is understood by and between the parties hereto
that the foregoing covenant by B Jensen not to enter into competition with PDC
as set forth in Section 3(a) hereof is an essential

A(IV)-2
42
element of this Agreement and the Asset Purchase Agreement and that, but for
the agreement of B Jensen to comply with such covenant, PDC would not have
agreed to enter into this Agreement or the Asset Purchase Agreement. PDC and B
Jensen have independently consulted with their respective counsel and have been
advised in all respects concerning the reasonableness and propriety of such
covenant, with specific regard to the nature of the business conducted by PDC
and its affiliates. B Jensen agrees that such covenant is reasonable in scope,
geographic area, and duration, and that compliance with such covenant would not
impose economic or professional hardship on B Jensen.

4. Restrictions on Soliciting Business of PDC.

B Jensen further covenants and agrees that during the
Non-Compete Period, B Jensen will not, either for himself or for any other
person or entity, directly or indirectly, engage in any of the following
activities in a Competitive Business without the express prior written consent
of PDC:

(a) Solicit or hire any of the employees of PDC or
solicit or take away any of PDC's customers, lessors, or suppliers or attempt
any of the foregoing:

(b) Acquire or attempt to acquire rights providing any
product or service in a Competitive Business within the territory described in
Section 3 hereof; or

(c) Engage in any act which would interfere with or harm
any business relationship PDC has with any customer, lessor, employee,
principal or supplier.

5. Specific Performance.

Without intending to limit the remedies available to PDC, B
Jensen acknowledges that PDC will have no adequate remedies at law if B Jensen
violates the terms of Section 3 or 4, hereof. In such event, B Jensen agrees
that PDC shall have the right, in addition to any other rights it may have, to
obtain in any court of competent jurisdiction specific performance of such
Sections of this Agreement or injunctive relief to restrain any breach or
threatened breach thereof. Nothing herein shall be construed as prohibiting
PDC from pursuing any other remedies available to PDC (whether at law or in
equity) for such breach or threatened breach, including, without limitation,
the recovery of monetary damages from B Jensen.

The provisions of this Section 5 shall survive the expiration,
termination or cancellation of this Agreement.

6. Attorneys Fees and Costs.

A(IV)-3
43
7. Representations and Warranties of PDC and B Jensen.

(a) Representations and Warranties of PDC. PDC hereby
represents and warrants to B Jensen that: (i) it has all requisite power to
enter into and perform its obligations under this Agreement; (ii) this
Agreement has been duly and validly authorized by all necessary corporate
action on the part of PDC; (iii) the execution of this Agreement by PDC and
performance of PDC's obligations hereunder do not require the consent or
approval of any other party; and (iv) this Agreement is a valid and binding
obligation of PDC.

(b) Representations and Warranties of B Jensen. B Jensen
hereby represents and warrants to PDC that: (i) B Jensen has the capacity and
power to enter into and perform obligations of B Jensen under this Agreement;
(ii) B Jensen has duly and validly executed this Agreement; (iii) the execution
of this Agreement and performance of obligations of B Jensen hereunder do not
require the consent or approval of any other party; and (iv) this Agreement
constitutes a valid and binding obligation of B Jensen.

8. General Provisions.

A(IV)-4
44
(e) Assignability. This Agreement will be binding upon
the parties' respective successors and permitted assigns. Neither party may
assign this Agreement and/or any of its rights and/or obligations hereunder
without the prior written consent of the other party, and any such attempted
assignment will be void; provided, however, that PDC may assign this Agreement
to a subsidiary or affiliate without the prior written consent of B Jensen, and
provided further that a transfer by PDC as a result of a merger or sale of all
or substantially all of the assets of PDC with or to a third party that assumes
PDC's obligations hereunder by operation of law or otherwise shall not
constitute a prohibited assignment under this Section 8(e).

(h) Headings. The titles of the Sections and subsections
of this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

To PDC:

Patterson Drilling Company
4510 Lamesa Highway
P.O. Drawer 1410
Snyder, Texas 79550
Facsimile: (915) 573-0281
Attention: A. Glenn Patterson
President and Chief Operating Officer

A(IV)-5
45
To B Jensen:

Billy Jensen
1731 W. Alabama
Hobbs, New Mexico 88240

with copies to:

Tommy D. Parker, Esq.
206 West Snyder
Hobbs, New Mexico 88740

IN WITNESS WHEREOF, the undersigned have caused this Agreement
to be executed by their respective representatives as of the day and year first
above written.

"PDC"

PATTERSON DRILLING COMPANY

By:
-------------------------------------
A. Glenn Patterson
President

"B JENSEN"

----------------------------------------
Billy Jensen

A(IV)-6
46
EXHIBIT A(V)

PATTERSON DRILLING COMPANY

NON-COMPETITION AGREEMENT

THIS NON-COMPETITION AGREEMENT is made and entered into this
_____ day of April, 1997 (this "Agreement"), by and between PATTERSON DRILLING
COMPANY, a Delaware corporation ("PDC"), and LEE ROBERSON, an individual
residing in Hobbs, New Mexico ("L Roberson").

RECITALS:

A. Simultaneously with the execution of this Agreement,
PDC has entered into that certain Asset Purchase Agreement, dated of even date
herewith (the "Asset Purchase Agreement"), between PDC and ZIADRIL, Inc.
("ZIADRIL"), providing for, among other things, the purchase by PDC of the
drilling rigs, related equipment, rolling stock and office equipment owned by
ZIADRIL.

B. L Roberson is a consultant to ZIADRIL.

C. The execution and delivery of this Agreement is a
condition to the consummation of the Asset Purchase contemplated by the Asset
Purchase Agreement, and the parties are entering into this Agreement in order
to fulfill such condition.

1. Period of Agreement.

The period of this Agreement shall commence on the date hereof
and remain in effect through May 1, 2002, unless sooner terminated as the
result of the death of L Roberson (the "Non-Compete Period").

2. Compensation.

Simultaneously with the execution of this Agreement, PDC has
paid L Roberson, by cashier's check, the amount of $450,000 as compensation for
entering into this Agreement.

Exh A(V)-1
47
3. Covenant Not to Compete.

(a) L Roberson covenants and agrees that during the
Non-Compete Period, L Roberson shall not, without the prior written consent of
PDC, directly or indirectly, and whether as a principal or as an agent,
officer, director, employee, consultant, or otherwise, alone or in association
with any other person, carry on, be engaged, concerned, or take part in, render
services to, or own, share in the earnings of, or invest in the stock, bonds,
or other securities of, any person which is engaged in, the contract oil and
gas well drilling business within the Permian Basin of West Texas and
Southeastern New Mexico (the "Competitive Business"); provided, however, that L
Roberson may (1) be employed by a Competitive Business as long as he is
employed in an accounting or similar role and does not have or attempt to have
contact with customers or potential customers of the Competitive Business and
does not otherwise act in a manner which would violate Section 4 hereof; and
(2) invest in stock, bonds, or other securities of any Competitive Business
(but without otherwise participating in the Competitive Business) if: (A) such
stock, bonds, or other securities are listed on any national securities
exchange or are registered under Section 12(g) of the Securities Exchange Act
of 1934, as amended; (B) the investment does not exceed, in the case of any
class of capital stock of any one issuer, two percent (2%) of the issued and
outstanding shares, or, in the case of bonds or other securities of any one
issuer, two percent (2%) of the aggregate principal amount thereof issued and
outstanding; and (C) such investment would not prevent, directly or indirectly,
the transaction of business by PDC or any affiliate of PDC with any state,
district, territory, or possession of the United States or any governmental
subdivision, agency, or instrumentality thereof by virtue of any statute, law,
regulation or administrative practice. The period of time during which L
Roberson is prohibited from engaging in certain activities by this Section
shall be extended by the length of time during which L Roberson is in breach of
the terms of this section.

(b) It is understood by and between the parties hereto
that the foregoing covenant by L Roberson not to enter into competition with
PDC as set forth in Section 3(a) hereof is an essential element of this
Agreement and the Asset Purchase Agreement and that, but for the agreement of L
Roberson to comply with such covenant, PDC would not have agreed to enter into
this Agreement or the Asset Purchase Agreement. PDC and L Roberson have
independently consulted with their respective counsel and have been advised in
all respects concerning the reasonableness and propriety of such covenant, with
specific regard to the nature of the business conducted by PDC and its
affiliates. L Roberson agrees that such covenant is reasonable in scope,
geographic area, and duration, and that compliance with such covenant would not
impose economic or professional hardship on L Roberson.

4. Restrictions on Soliciting Business of PDC.

L Roberson further covenants and agrees that during the
Non-Compete Period, L Roberson will not, either for himself or for any other
person or entity, directly or indirectly, engage in any of the following
activities in a Competitive Business without the express prior written consent
of PDC:

(a) Solicit or hire any of the employees of PDC or
solicit or take away any of PDC's customers, lessors, or suppliers or attempt
any of the foregoing:

Exh A(V)-2
48
(b) Acquire or attempt to acquire rights providing any
product or service in a Competitive Business within the territory described in
Section 3 hereof; or

(c) Engage in any act which would interfere with or harm
any business relationship PDC has with any customer, lessor, employee,
principal or supplier.

5. Specific Performance.

Without intending to limit the remedies available to PDC, L
Roberson acknowledges that PDC will have no adequate remedies at law if L
Roberson violates the terms of Section 3 or 4, hereof. In such event, L
Roberson agrees that PDC shall have the right, in addition to any other rights
it may have, to obtain in any court of competent jurisdiction specific
performance of such Sections of this Agreement or injunctive relief to restrain
any breach or threatened breach thereof. Nothing herein shall be construed as
prohibiting PDC from pursuing any other remedies available to PDC (whether at
law or in equity) for such breach or threatened breach, including, without
limitation, the recovery of monetary damages from L Roberson.

The provisions of this Section 5 shall survive the expiration,
termination or cancellation of this Agreement.

6. Attorneys Fees and Costs.

7. Representations and Warranties of PDC and L Roberson.

(a) Representations and Warranties of PDC. PDC hereby
represents and warrants to L Roberson that: (i) it has all requisite power to
enter into and perform its obligations under this Agreement; (ii) this
Agreement has been duly and validly authorized by all necessary corporate
action on the part of PDC; (iii) the execution of this Agreement by PDC and
performance of PDC's obligations hereunder do not require the consent or
approval of any other party; and (iv) this Agreement is a valid and binding
obligation of PDC.

(b) Representations and Warranties of L Roberson. L
Roberson hereby represents and warrants to PDC that: (i) L Roberson has the
capacity and power to enter into and perform obligations of L Roberson under
this Agreement; (ii) L Roberson has duly and validly executed this Agreement;
(iii) the execution of this Agreement and performance of obligations of L
Roberson hereunder do not require the consent or approval of any other party;
and (iv) this Agreement constitutes a valid and binding obligation of L
Roberson.

Exh A(V)-3
49
8. General Provisions.

(e) Assignability. This Agreement will be binding upon
the parties' respective successors and permitted assigns. Neither party may
assign this Agreement and/or any of its rights and/or obligations hereunder
without the prior written consent of the other party, and any such attempted
assignment will be void; provided, however, that PDC may assign this Agreement
to a subsidiary or affiliate without the prior written consent of L Roberson,
and provided further that a transfer by PDC as a result of a merger or sale of
all or substantially all of the assets of PDC with or to a third party that
assumes PDC's obligations hereunder by operation of law or otherwise shall not
constitute a prohibited assignment under this Section 8(e).

Exh A(V)-4
50
provision that approximates the intent and economic effect of the invalid
provision as closely as possible.

(h) Headings. The titles of the Sections and subsections
of this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

To PDC:

Patterson Drilling Company
4510 Lamesa Highway
P.O. Drawer 1410
Snyder, Texas 79550
Facsimile: (915) 573-0281
Attention: A. Glenn Patterson
President and Chief Operating Officer

To L Roberson:

Lee Roberson
3305 N. Grimes
Hobbs, New Mexico 88240

with copies to:

Tommy D. Parker, Esq.
206 West Snyder
Hobbs, New Mexico 88240

Exh A(V)-5
51
IN WITNESS WHEREOF, the undersigned have caused this Agreement
to be executed by their respective representatives as of the day and year first
above written.

"PDC"

PATTERSON DRILLING COMPANY

By:
-------------------------------------
A. Glenn Patterson
President

"L ROBERSON"

----------------------------------------
Lee Roberson

Exh A(V)-6
52
EXHIBIT B

BILL OF SALE AND ASSIGNMENT

KNOW ALL MEN BY THESE PRESENTS, that, pursuant to that certain
Asset Purchase Agreement, dated of even date herewith ("Asset Purchase
Agreement") between PATTERSON DRILLING COMPANY ("PDC"), a Delaware corporation,
and ZIADRIL, Inc. ("ZIADRIL"), a New Mexico corporation (ZIADRIL is referred to
herein as the "Assignor"), the Assignor, for good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, hereby grants,
bargains, sells, conveys and transfers unto PDC (the "Assignee"), all of the
Assignor's right, title and interest in and to (i) the Drilling Rigs, Equipment
and Vehicles set forth in Appendix I attached hereto and incorporated herein by
this reference; and (ii) the Drilling Contracts and Other Agreements described
in Appendix II attached hereto and incorporated herein by this reference.

TO HAVE AND TO HOLD the same unto the Assignee and the
Assignee's successors and assigns forever. The Assignor hereby covenants and
agrees that it has the full right, power and authority to sell, convey and
transfer the foregoing property to the Assignee pursuant to this Bill of Sale
and Assignment.

IN WITNESS WHEREOF, the Assignor has caused this Bill of Sale
and Assignment to be duly executed by its duly authorized officer as of the
____ day of April, 1997.

ZIADRIL, INC.

By:
-------------------------------------
Joe Smith
President

Exh B-1
53
APPENDIX I
TO
BILL OF SALE AND ASSIGNMENT
FROM
ZIADRIL, INC.
TO
PATTERSON DRILLING COMPANY
(LIST OF ASSETS ASSIGNED)

A. DRILLING RIGS AND EQUIPMENT

RIG NO. 2

DRAWWORKS

EMSCO GB-800 Single Drum Drawworks, S/N-13, 1000 HP, LEBUS Grooved
f/1-l/4" Line, Makeup & Breakout Catheads, Overrunning Clutch, Air
Driller's Console, Crown-O-Matic

COMPOUND

EMSCO 2-Engine Compound, S/N-N/A, w/Single Pedestal Pump Drive, (2)
QUINCY 325 Air Compressors, S/Ns-720033 & 231186, w/Covered Skid

BRAKE

PARKERSBURG 46" Double Hydromatic Brake, S/N-N/A

ENGINES

(2) CAT D379 610 HP Diesel Engines, S/Ns-68B0703 & N/A, w/Air
Starters, Radiators, Gauges, Air Clutches

MAST

1979 PYRAMID 136'H Cantilever Mast, S/N-DAM536791, 600,000# Static
Hook Load, Pin-Type, Crown Block w/(6) Sheaves, Fastline Sheave,
1-1/4" Line, 4" Standpipe, Crown Safety Platform, Racking Board, Tong
Counterweights, Ladder, Derrick Climber, Geronimo, Boom, Mast Stand,
Standpipe Manifold w/4" & 2" Gate Valves

SUBSTRUCTURE

15'H x 25'W x 58'L Box-On-Box Substructure w/Engine Stepdown, Rotary
Beams, V-Door Ramp, (4) Stairs, Safety Rails, Deadline Anchor, MISSION
1-1/2" x 2" Washdown Pump p/b Compound, Steel Windwalls w/Windwall
Box, QUINCY Air Compressor p/b LISTER ST3A Diesel Engine

Exh B-2
54
RIG NO. 2

PUMPS

CONTINENTAL EMSCO DC-1000 Duplex Mud Pump. S/N-190, 1000 HP, Cast
Steel Fluid End w/Quick-Change Caps, HYDRIL K-20-5000 Pulsation
Dampener, S/N-N/A, CONTINENTAL EMSCO 2" Shear Relief Valve, Rod
Cooling Pump, Drive Assembly, Skidded, Compound Driven

CONTINENTAL EMSCO DA-850 Duplex Mud Pump, S/N-87, 850 HP, 7-1/2" x
16", MATTCO Forged Steel Fluid End w/Quick- Change Caps, HYDRIL
K-20-3000 Pulsation Dampener, CONTINENTAL EMSCO 2" Shear Relief Valve,
Rod Cooling Pump, Type D Rebuilt 3000 PSI Pressure Gauge, S/N-RH452,
Drive Assembly, Skidded w/Engine

PUMP POWER

CAT D379 610 HP Diesel Engine, S/N-N/A, Air Starter, Radiator, Gauges,
Air Clutch

ROTATING EQUIPMENT

GARDNER-DENVER 27-1/2 27-1/2" x 53-1/4" Rotary Table, S/N-N/A,
Pin-Type Master Bushing

OIL WELL PC-425 425-Ton Swivel, S/N-N/A

5-1/4" x 40'L Square Kelly

VARCO HD Kelly Drive Bushing, Pin-Type

Upper Kelly Valve

Lower Kelly Valve

Inside Blowout Preventer

TRAVELING EQUIPMENT

GARDNER-DENVER 300-Ton Block, S/N-N/A, w/(5) Sleaves, 1-1/4" Line

BJ Dynaplex 5350 350-Ton Hook, S/N-N/A

3-1/2" x 120" Elevator Links

WELL CONTROL EQUIPMENT

HYDRIL GK-12-900 13-5/8" 3000 PSI Annular Blowout Preventer, S/N-N/A

SHAFFER Type B 13-5/8" 3000 PSI Double Blowout Preventer w/4-1/2" Pipe
& Blind Rams, S/N-N/A

26"H x 13-5/8" 3000 PSI x 11" 3000 PSI, 10"H x 13-5/8" 3000 PSI x 11"
3000 PSI & 12"H x 13-5/8" 2000/3000 PSI x 11" 2000/3000 PSI Adapter
Spools, 13-5/8" 5000 PSI x 11" 5000 PSI DSA

KOOMEY T-20180-3S 6-Station Closing Unit, S/N-1452801, w/279.3-Gallon
Hydraulic Fluid Reservoir, Air-Operated Hydraulic Pump, Triplex
Hydraulic Pump w/Electric Motor, (18) 10-Gallon Bladder-Type
Separator/Accumulators, Skidded w/Lift Frame

(14) Approximately 20'L x 1"ID Hydraulic Lines w/Hammer Unions

Exh B-3
55
RIG NO. 2

(6) Steel Flex Lines

W-K-M 5000 PSI Blowout Preventer Choke Manifold w/4-1/16" x 2-1/16"
Studded Cross, (4) 2-1/16" Gate Valves, 4- 1/16" Gate Valves, (2) 2"
Adjustable Chokes, Separate Buffer Chamber w/(4) DEMCO 4" Gate Valves,
(2) 2" Ball Valves, On Adjustable Support

RIG HOUSES

TETON HOMES 10'W x 40'L Toolpusher's House, S/N-N/A, Fully Furnished,
Skidded

10'W x 24'L Doghouse w/Knowledge Box, (5) Lockers, Bench Storage,
Cabinets, Parts Bins, Fluorescent Lights, Heater, Skidded

WIZARD Automatic Driller

7'W x 24'L Change House w/Round Top, (16) Lockers, Bench Storage,
Cabinets, Fluorescent Lights, Heaters, Skidded

7'6"W x 30'L Mud House w/Round Top, (3) Triangular Supports,
Fluorescent Lights, Skidded

UTILITY HOUSE/GENERATORS

CAT SR-4 210 KW AC Generator Set, S/N-5HA01491, w/CAT 3406 Diesel
Engine, S/N-90UI3488, Air Starter, Radiator, Gauges, Skidded

CAT SR-4 260 KW AC Generator Set, S/N-48BH3749, w/CAT 3406PC Diesel
Engine, S/N-90U5379, Electric Starter, Radiator, Gauges, Skidded

QUINCY 350 Air Compressor, S/N-184555, w/DYNA 10 HP Electric Motor,
Approximately 200-Gallon Air Receiver Tank

SQUARE D Electrical Controls

All Above Mounted in 9'8"W x 36'L Utility House w/Round Top, 11'L
Parts Room, Fluorescent Lights, Heater, Skidded

MUD SYSTEM

8'W x 6'H x 36'L Crimped-Steel Mud Suction Tank w/(2) Compartments,
Round Bottom, Internal Plumbing, Top & Side-Mounted Walkways, Stairs,
Safety Rails, Skidded

MISSION Magnum 5" x 6" Centrifugal Pump, S/N-N/A, w/50 HP Electric
Motor, Skidded

8'W x 6'H x 36'L Mud Slugging Tank w/Single-Compartment, Round Bottom.
Internal Plumbing, Top & Side-Mounted Walkways, Mud Hopper, Safety
Rails, Skidded

8'W x 6'H x 36'L Crimped-Steel Mud Volume Tank, Single-Compartment,
Round Bottom, Internal Plumbing, Top & Side-Mounted Walkways, Stairs,
Safety Rails, Skidded

8'W x 6'H x 36'L Crimped-Steel Mud Shaker Tank w/(3) Compartments,
Round Bottom, Internal Plumbing

Exh B-4
56
RIG NO. 2

WATER/FUEL TANKS

(2) 10'6"Dia x 32'L 500-Barrel Water Tanks, Skidded, (1) w/REEDY
2" x 3" Centrifugal Pump p/b 25 HP Electric Motor

7'4"Dia x 8'H Freshwater Tank, Skidded

4'Dia x 13'L 4-Compartment Lubester, Skidded

HANDLING TOOLS

WOOLLEY B Tongs w/Heads

WOOLLEY 4-1/2"BN Drill Pipe Elevators

BJ MAA 8"SS Elevators

WILSON 7"SS Center Latch Drill Collar Elevators

WOOLLEY Long Drill Pipe Slips

WOOLLEY 10-Segment Drill Collar Slips

WOOLLEY 11-Segment Drill Collar Slips

Drill Collar Safety Clamp

(27) Drill Collar Lift Nubbins

INGERSOLL-RAND H5UL Air Hoist, S/N-RFH85167

Mud Bucket

AUXILIARY EQUIPMENT

TOTCO 100 800,000# Capacity Weight Indicator w/Pump Pressure, Tong
Line Pull & Rotary Torque Gauges

TOTCO 4 Mud Gauge, S/N-3474R

3-1/2"ID x 55'L Rotary Hose

(2) 10"ID x 5'L Suction Hoses

(2) 3"ID x 12'L Vibrator Hoses

42"H x 5'6"W x 56'L 2-Section Catwalk w/Steel Deck

30"H x 5'W x 10'L Junk Box w/Lift Frame

(7) 33"H to 36"H x 7'W to 7'6"W x 34'L Pipe Tubs

2 Sets (4) 42"H x 28'L Rectangular Pipe Racks

Exh B-5
57
RIG NO. 2

2 Sets (4) 42"H x 28'L Triangular Pipe Racks

CEDCO Wireline Measuring Device

(16) Miscellaneous Drill Collar Subs

Rathole & Mousehole

Fluorescent Rig Lights w/Wiring

Approximately 6000' of 1-1/4" Drill Line w/Spool, Stand

Miscellaneous Spare Parts, Hand Tools, Valves, Fire Extinguishers, Etc

TOTAL RIG NO. 2 W/O TUBULARS:

DRILL PIPE

1023 (33 Joints) 4-1/2", Grade X-95, 22.82#, Range 2 Drill Pipe
w/4-1/2"XH Tool Joints, 6-1/8"OD to 6-1/4"OD

Approximately 4495' (145 Joints) 4-1/2", Grade X-95, 16.60#, Range 2
Drill Pipe w/4-1/2"XH Tool Joints, 5- 15/16"OD to 6-1/8"OD

Approximately 8990' (290 Joints) 4-1/2", Grade E, 16.60#, Range 2
Drill Pipe w/4-1/2"XH Tool Joints, 5-7/8"OD to 6"OD

DRILL COLLARS

(13) 5-3/4"OD to 5-13/16"OD x Approximately 29'L Drill Collars
w/4-1/2"H-90 Connections

(23) 6-15/16"OD to 6-3/8"OD x Approximately 29'L Drill Collars
w/5"H-90 Connections

(21) 7-3/4"OD x Approximately 29'L Drill Collars w/6-5/8"H-90
Connections

TOTAL RIG NO. 2 W/TUBULARS:

Exh B-6
58
RIG NO. 3

RIG NO. 3

DRAWWORKS

MID-CONTINENT U-712-A Single Drum Drawworks, S/N-59, 1200 HP, LEBUS
Grooved f/1-1-4" Line, KELCO Makeup & Breakout Catheads, Overrunning
Clutch, Air Driller's Console, Crown-O-Matic

COMPOUND

UNIT RIG & EQUIPMENT 2-Engine Compound, S/N-57, w/Single Pedestal Pump
Drive, (2) QUINCY 325 Air Compressors, S/Ns-200921 & N/A

BRAKE

PARKERSBURG 46RC Double Hydromatic Brake, S/N-P20369

ENGINES

(2) CAT D379 610 HP Diesel Engines, S/Ns-N/A, (1) w/LISTER Pony
Start, (2) w/Air Starters, Radiators, Gauges, Air Clutches

MAST

LEE C. MOORE 131'H Cantilever Mast, S/n-T3424, 550,000# GNC, Pin-Type,
Crown Block w/(5) 42" Sheaves, 56" Fastline Sheave, 1-1/8" Line, 4"
Standpipe, Crown Safety Platform, Racking Board, Tong Counterweights,
Ladder, Derrick Climber, Geronimo, Boom, Mast Stand, Standpipe
Manifold w/4" & 2" Gate Valves

SUBSTRUCTURE

LEE C. MOORE 18'H x 20'W x 46'L Box-On-Box Substructure w/-4'W Folding
Side Extensions, Rotary Beams, V-Door Ramp, (4) Stairs, Safety Rails,
NATIONAL Deadline Anchor, Steel Windwalls w/Windwall Box, 5'W x 7'H x
5'L Stair Landing/Parts House

PUMPS

CONTINENTAL EMSCO DB-7OO Duplex Mud Pump, S/N241, 700 HP, 7-1/2" x
16", Cast Steel Fluid End w/Quick-Change Caps, HYDRIL K-20-3000
Pulsation Dampener CONTINENTAL EMSCO 2" Shear Relief Valve, Rod
Cooling Pump, Drive Assembly, Skidded, Compound Driven

EMSCO DB-550 Duplex Mud Pump, S\N-47, 550 HP, 7-1/2", MATTCO Forged
Steel Fluid End w/Quick-Change Caps, HYDRIL K-20-3000 Pulsation
Dampener, SN-N/A, DEMCO 2" Shear Relief Valve, Rod Cooling Pump,
CAMERON Type F 3000 PSI Pressure Gauge, S/N-67000, Drive Assembly,
Skidded, Master Skidded w/Engine

PUMP POWER

CAT D379 Diesel Engine, S/N-68B4510, Air Starter, Radiator, Gauges
w/Air Clutch

Exh B-7
59
RIG NO. 3

ROTATING EQUIPMENT

OILWELL A27-1/2 27-1/2" x 53-1/4" Rotary Table, S/N-N/A, Split Master
Bushing

NATIONAL N-69 Swivel

4-1/2" x 40'L Square Kelly

3-1/2"x 40'L Square Kelly

VARCO HD Kelly Drive Bushing

Upper Kelly Valve

Lower Kelly Valve

Inside Blowout Preventer

TRAVELING EQUIPMENT

IDECO 360-Ton Block, S\N-N/A, w/(5) 50" Sheaves, 1-1/8 Line

WEB WILSON Hydra Hook 350-Ton Hook, S/N-N/A

3-1/2" x 132" Elevator Links

WELL CONTROL EQUIPMENT

SHAFFER SPH 5000 PSI Annular Blowout Preventer, S/N-N/A

SHAFFER LWS 11" 5000 PSI Double Blowout Preventer w/4-1/2" Pipe &
Blind Rams, S/N-N/A

24"H x 11"ID 5000 PSI Drilling Spool w/4-1/16" Outlets, (2) 4-1/16"
Manual Gate Valves, 2-1/16" Gate Valve, Check Valve

CAMERON 4-1/16" 5000 PSI Gate Valve, 21"H x 11" 5000 PSI x 11" 3000
PSI & 21"H x 11" 3000 PSI x 13-5/8" 3000 PSI Adapter Spools

KOOMEY '80 120-11SX 6-Station Closing Unit, S/N-2527, w/14"W x 36"H x
10'6"L Hydraulic Fluid Reservoir, (2) Air-Operated Hydraulic Pumps,
(12) 10-Gallon Bladder-Type Separator/Accumulators, Approximately 100'
of Control Cable, Skidded

(3) 10' Suitcase Sections w/(9) Lines Each of Hydraulic Lines

(9) Approximately 10'L Steel Flex Hoses

KOOMEY '80 A6GRB 6-Station Remote Closing Unit, S/N-2527

W-K-M 5000 PSI Blowout Preventer Choke Manifold w/4-1/16" x 2-1/16"
Flanged Cross, (4) 2-1/16" Gate Valves, (1) 4-1/16" Gate Valve, (2) 2"
Adjustable Chokes, On Adjustable Stand

Buffer Chamber w/(4) DEMCO 4" Gate Valves, (2) 2" Ball Valves, On
Adjustable Stand

Exh B-8
60
RIG NO. 3

RIG HOUSES

TETON HOMES 10'W x 40'L Toolpusher's House, Fully Furnished

10'W x 24'L Doghouse w\Round Top, Knowledge Box, (6) Lockers, Bench
Storage, Cabinets, Parts Bins, Fluorescent Lights, Heater, Skidded

SATELLITE Apollo Automatic Driller, S/N-N/A

8'W x 24'L Crimped-Steel Change House w/Round Top, (16) Lockers, Bench
Storage, Cabinets, Fluorescent Lights, Heater, Skidded

7'6"W x 30'L Mud House w/Round Top, (3) Triangular Supports,
Fluorescent Lights, Skidded

GENERATORS/UTILITY HOUSE

CAT SR-4 155 KW AC Generator Set, S/N-5EA03043, w/CAT 3306PC Diesel
Engine, S/N-66D45979, w/Air Starter, Radiator, Gauges

CAT SR-4 155 KW AC Generator Set, S/N-5EA03040, w/CAT 3306 Diesel
Engine, S/N-N/A, w/Electric Starter, Radiator, Gauges

QUINCY 390 Air Compressor, S/N-212458, w/BALDOR Electric Motor, Air
Receiver Tank

QUINCY 5120 Air Compressor, S/N-213663, w/BALDOR Electric Motor

Electrical Controls

All Above Mounted in 9'10"W x 35'L Utility House w/round Top,
Fluorescent Lights, Heater, Skidded

MUD SYSTEM

7'6"W x 6'H x 36'L Mud Suction Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

HARRISBURG 6" x 8" Centrifugal Pump, S/N-N/A, w/GE 50 HP Electric
Motor, Skidded

7'6"W x 5'H x 34'L Mud Slugging Tank w/Single-Compartment, Round
Bottom, Internal Plumbing, Top & Side-Mounted Walkways, Safety Rails,
Skidded

7'6"W x 6'H x 36'L Mud Volume Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

7'6"W x 6'H x 36'L Mud Shaker Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

WATER/FUEL TANKS

(2) 10'6"Dia x 32'L Water Tanks, Skidded, (1) w/2" x 3"
Centrifugal Pump p/b Electric Motor

7'4" Dia x 8'H Water Tank, Skidded

4' Dia x 13'L 4-Compartment Lubester, Skidded

Exh B-9
61
RIG NO. 3

HANDLING TOOLS

WOOLLEY B Tongs w/Heads

WOOLLEY 4-1/2"BN Drill Pipe Elevators

WILSON 7"SS Center Latch Elevators

WTM SS150 7" Center Latch Drill Collar Elevators

WOOLLEY Long 4-1/2" Drill Pipe Slips

WOOLLEY 10-Segment Drill Collar Slips

WOOLLEY 11-Segment Drill Collar Slips

Drill Collar Safety Clamp

(25) Drill Collar Lift Nubbins

INGERSOLL-RAND K5UL Air Hoist, S/N-RCM86901

Mud Bucket

AUXILIARY EQUIPMENT

TOTCO 75 600,000# Capacity Weight Indicator w/Pump Pressure, Tong
Line Pull & Rotary Torque Gauges

TOTCO 4 Mud Gauge, S/N-43219

3-1/2"ID x 55'L Rotary Hose

(2) 10"ID x 6'L Suction Hoses

CEDCO 275A Wireline Measuring Device, S/N-435

(2) 3"ID x 12'L Vibrator Hoses

42"H x 6'W x 58'L 2-Section Catwalk w/Steel Deck

28"H x 7'6"W x 11'8"L Junk Box

(10) 33"H to 36"H x 7'W to 7'6"W x 34'L Pipe Tubs

4 Sets (8) 42"H x 28'L Triangular Pipe Racks

(12) Miscellaneous Drill Collar Subs, (1) Junk Sub

Rathole & Mousehole

Fluorescent & Mercury-Vapor Rig Lights w/Wiring

Approximately 2500' of 1-1/4" Drill Line w/Spool, Stand

Exh B-10
62
RIG NO. 3

BRANDT B150 Bug Blower, S/N-8235

(4) 6'W x 24'6"L Steel-Framed Wood Rig Mats f/Substructure

Miscellaneous Spare Parts, Hand Tools, Valves, Fire Extinguisher, Etc

TOTAL RIG NO. 3 W/O TUBULARS:

DRILL PIPE

1550' (50 Joints) 4-1/2", Grade X-95, 22.82#, Range 2 Drill Pipe
w/4-1/2"XH Tool Joints, 6-1/8"OD to 6-1/4"OD

Approximately 13,640' (440 Joints) 4-1/2", Grade E, 16.60#, Range 2
Drill Pipe w/4-1/2"XH Tool Joints, 6- 3/16"OD to 6"OD

Approximately 13,900' (448 Jts) 3-1/2", Grade E, 13.30# Range 2 Drill
Pipe w/3-1/2"IF Tool Joints, 4-11/16"OD to 4-5/8"OD

DRILL COLLARS

(28) 6"OD to 6-11/16"OD x Approximately 29.50'L Drill Collars
w/4-1/2"XH Connections

(15) 7-9/16"OD to 7-3/4"OD x Approximately 29'L Drill Collars
w/6-5/8"H-90 Connections

(35) 4-13/16"OD to 4-7/8"OD x Approximately 29.25'L Drill Collars
w/3-1/2"IF Connections

TOTAL RIG NO. 3 W/TUBULARS:

Exh B-11
63
RIG NO. 6

RIG NO. 6

DRAWWORKS

SKYTOP BREWSTER N-75 Single Drum Drawworks, S/N-750026, 750 HP, LEBUS
Grooved f/1-1/4" Line, FOSTER, Catheads, Overrunning Clutch, Air
Driller's Console Controls, Crown-O-Matic

COMPOUND

3-Engine In-Line Compound w/Single Pedestal Pump Drive, (2) QUINCY 370
Air Compressors, Covered Skid

BRAKE

PARMAC 342 34" Double Hydromatic Brake, S/N-N/A

ENGINES

(3) CAT D-353E 410 HP Diesel Engines, S/Ns-46B7963, 46B8328 & 46B8138,
(1) w/LISTER Pony Start w/TWIN DISC Torque Converter, S/N-15506, (2)
w/Air Starters, Radiators, Gauges, Air Clutches

MAST

TRI-STAR 133'H Cantilever Mast, S/N-N/A, 550,000# GNC, Pin-Type, Crown
Block w(4) Sheaves, (1) Fastline Sheave, 1-1/8" Line, 4" Standpipe,
Crown Safety Platform, Racking Board, Tong Counterweights, Ladder,
Derrick Climber, Geronimo, Boom, Mast Stand, Standpipe Manifold w/4" &
2" Gate Valves

SUBSTRUCTURE

TRI-STAR 17'H x 24'8"W x 42'L Box-On-Box Substructure W/Rotary Beams,
V-Door Ramp, Stairs, Safety Rails, Deadline Anchor, 5'W x 7'H x 5'L
Stair Landing/Parts House, Steel Windwalls

PUMPS

CONTINENTAL EMSCO DC-700 Duplex Mud Pump), S/N-271, 700 HP, 7-1/2" x
16". Forged Steel Fluid End w/Quick- Change Caps, GM MATTCO Pulsation
Dampener, S/N-200507, CONTINENTAL EMSCO 2" Shear Relief Valve, Rod
Cooling Pump, Drive Assembly, Skidded, Compound Driven

EMSCO DC-700 Duplex Mud Pump, S/N-N/A, 700 HP, 7-1/2" x 14", Cast
Steel Fluid End w/Quick-Change Caps, CONTINENTAL EMSCO PD-53 Pulsation
Dampener, S/N-N/A, DEMCO 2" Shear Relief Valve, Rod Cooling Pump,
Drive Assembly, Master Skidded w/Engine

PUMP POWER

CAT D379 600 HP Diesel Engine, S/N-N/A, Air Starter, Radiator, Gauges
w/Air Clutch

ROTATING EQUIPMENT

OILWELL A20-1/2 20-1/2" x 53-1/4" Rotary Table, S/N-N/A, Split Master
Bushing

NATIONAL N-47 200-Ton Swivel

Exh B-12
64
RIG NO. 6

4-1/4" x 40'L Square Kelly

VARCO HD Kelly Drive Bushing

Upper Kelly Valve

Lower Kelly Valve

Inside Blowout Preventer

TRAVELLING EQUIPMENT

BREWSTER Block/Hook Combination w/BJ 5250 Unimatic Hook

3-1/2" x 120" Elevator Links

WELL CONTROL EQUIPMENT

SHAFFER SPH 11" 5000 PSI Annular Blowout Preventer, S/N-N/A

SHAFFER LWS 11" 5000 PSI Double Blowout Preventer w/4-1/2" Pipe &
Blind Rams, S/N-N/A

24"H x 11"ID 5000 PSI Drilling Spool w/(2) 4-1/16" Outlets, (3)
4-1/16" Gate Valves

15"H x 11" Adapter Spool

1972 KOOMEY G26160-3B 6-Station Closing Unit, S/N-5002, w/375-Gallon
Hydraulic Fluid Reservoir, (2) Air- Operated Hydraulic Pumps, Triplex
Hydraulic Pump w/Electric Motor, (2) 80-Gallon Spherical Accumulators,
Skidded

(18) 1"ID x Approximately 20'L Steel Hydraulic Lines w/Hammer
Unions

KOOMEY 6-Station Remote Closing Unit, S/N-N/A, Mounted on Doghouse
Porch

BARTON 5000 PSI Blowout Preventer Choke Manifold w/4-1/16" x 2-1/16"
Studded Cross, (1) 4-1/16" Gate Valve, (5) 2-1/16" Gate Valves, 2"
Positive Choke, 2" Adjustable Choke, On Adjustable Stand, Buffer
Chamber w/(4) DEMCO 4" Gate Valves, (2) DEMCO 2" Gate Valves, On
Adjustable Stand

RIG HOUSES

TETON HOMES 10'W x 40'L Toolpusher's House, Fully Furnished, Skidded

10'W 24'L Doghouse w/Round Top, Knowledge Box, (6) Lockers, Bench
Storage, Cabinets, Part Bins, Fluorescent Lights, Heater, Skidded

SATELLITE Apollo Automatic Driller, S/N-N/A

7'6"W x 24'L Change House w/Round Top, (16) Lockers, Bench Storage,
Cabinets, Roof-Mounted Doghouse Supports, Fluorescent Lights, Heater,
Skidded

7'6"W x 26'L Mud House w/Round Top, Fluorescent Lights, Skidded

Exh B-13
65
RIG NO. 6

GENERATORS/UTILITY HOUSE

CAT 135 KW AC Generator Set, S/N-N/A, w/CAT 3306 Diesel Engine,
S/N-N/A, Electric Starter, Radiator, Gauges

CONDEC 135 KW AC Generator Set, S/N-BA11511CF, w/CAT D333 Diesel
Engine, S/N-66D7587, Air Starter, Radiator, Gauges

QUINCY 350 Air Compressor, S/N-N/A, w/Electric Motor, Air Receiver
Tank

All Above Mounted in 10'W x 25'L Utility House w/Round Top,
Fluorescent Lights, Skidded

MUD SYSTEM

7'6"W x 6'H x 36'L Mud Suction Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

REEDY 6" x 8" Centrifugal Pump, S/N-N/A, p/b 60 HP Electric Motor

7'W x 5'8"H x 30'L Mud Slugging Tank w/Single-Compartment, Round
Bottom, Internal Plumbing, Mud Hopper, Top & Side-Mounted Walkways,
Stairs, Safety Rails, Skidded

7'6"W x 6'H x 36'L Mud Volume Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

7'W x 6'H x 36'L Mud Shaker Tank, (2) Compartments, Mud Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

WATER/FUEL TANKS

(2) 10'Dia x 32'L Water Tanks, Skidded, 7'4"Dia x 8'H Water Tank,
Skidded, (1) w/2" x 3" Centrifugal Pump, Electric Motor

10'6"Dia x 32'L Brine Tank, Skidded

4'Dia x 13'L 4-Compartment Lubester, Skidded

HANDLING TOOLS

BJ Type B Tongs w/Heads

WTM 4-1/2"BN Drill Pipe Elevators

WOOLLEY Long 4-1/2" Drill Pipe Slips

WOOLEY 11-Segment Drill Collar Slips

WILSON Center Latch Drill Collar Elevators

Drill Collar Safety Clamp

(17) Drill Collar Lift Nubbins

Exh B-14
66
RIG NO. 6

INGERSOLL-RAND H5UL Air Hoist, S/N-35500

Mud Bucket

AUXILIARY EQUIPMENT

TOTCO 50 400,000# Capacity Weight Indicator w/Pump Pressure, Tong Line
Pull & Rotary Torque Gauges

TOTCO 4 Mud Gauge, S/N-11062R

3-1/2"ID x 55'L Rotary Hose

10"ID x 5'L Suction Hose

8"ID x 5'L Suction Hose

(2) 3-1/2"ID x 12'L Vibrator Hoses

42"H x 6'W x 60'L 2-Section Catwalk w/Steel Deck

24"H x 6'W x 10'L Junk Box, Skidded

(5) 33"H x 7'6"W x 34'L Pipe Tubs

3 Sets (6) 42"H x 28'L Triangular Pipe Racks

(13) Miscellaneous Drill Collar Subs, (2) Junk Subs

Rathole & Mousehole

Fluorescent Rig Lights w/Wiring

Approximately 7000' of 1-1/4" Drill Line w/Spool, Stand

Miscellaneous Spare Parts, Hand Tools, Valves, Fire Extinguishers,
Etc.

TOTAL RIG NO. 6 W/O TUBULARS:

DRILL PIPE

1550' (50 Joints) 4-1/2", Grade X-95, 22.82#, Range 2 Drill Pipe
w/4-1/2"XH Tool Joints, 6-1/8"OD to 6-1/4"OD

1550' (50 Joints) 4-1/2", Grade G, 22.82#, Range 2 Drill Pipe
w/4-1/2"XH Tool Joints, 6"OD to 6-1/4"OD, HB, PC

11.935' (385 Joints) 4-1/2", Grade E, 16.60#, Range 2 Drill Pipe
w/4-1/2"XH Tool Joints, 5-7/8"OD to 6-1/8"OD

DRILL COLLARS

(5) 6-3/8"OD x Approximately 29'L Drill Collars w/5"H-90
Connections

Exh B-15
67
RIG NO. 6

(21) 5-7/8"OD to 6-1/8"OD x Approximately 29'L Drill Collars
w/4-1/2"XH Connections

(21) 7-1/2"OD to 7-13/16"OD x Approximately 29.50'L Drill Collars
w/6-5/8"H-90 Connections

TOTAL RIG NO. 6 W/TUBULARS:

Exh B-16
68
RIG NO. 7

RIG NO. 7

DRAWWORKS

BREWSTER N-75 Single Drum Drawworks, S/N-2W25S, 1000 HP, LEBUS Grooved
f/1-1/4" Line, FOSTER Makeup & Breakout Catheads, Overrunning Clutch,
Air Driller's Console, Crown-O-Matic, Drawworks/Compound Shed Cover

COMPOUND

BREWSTER 2-Engine In-Line Compound w/Single Pedestal Pump Drive, (2)
QUINCY 325 Air Compressors, S/Ns-481589 & N/A

BRAKE

PARKERSBURG 46RC Double Hydromatic Brake, S/N-P17449, w/Overrunning
Clutch, Shifting Collar & Linkage

ENGINES

(2) CAT D379 Diesel Engines, S/Ns-68B6044 & 68B6611, Air Starters,
Radiators, Gauges, Air Clutches

MAST

LEE C. MOORE 131'H x 18'W Cantilever Mast, S/N-T3359, Approximately
475,000# Static Hook Load, Pin-Type, LEE C. MOORE Crown Block w/(5)
42" Sheaves, 56" Fastline Sheave, 1-1/4" Line, 3-1/2" Standpipe, Crown
Safety Platform, Racking Board, Tong Counterweights, Ladder, Derrick
Climber, Geronimo, Boom, Mast Stand, Standpipe Manifold w/4" Gate
Valve

SUBSTRUCTURE

15'6"H 21'10"W x 38'L Box-On-Box Substructure w/Rotary Beams, V-Door
Ramp, Air Volume Tank, (3) Stairs, Safety Rails, NATIONAL EB Deadline
Anchor, MISSION 2" X 3" Centrifugal Pump, Belt-Driven

PUMPS

CONTINENTAL EMSCO DB-700 Duplex Mud Pump, S/N-N/A, SOUTHWEST
Cast/Forged Steel Fluid End w/Quick-Change Caps, HYDRIL K-20 Pulsation
Dampener, DEMCO 2" Shear Relief Valve, Suction Screen, Rod Cooling
Pump, OTECO 4" Gate Valve, Belt Drive Assembly, Master Skidded,
Compound Driven

CONTINENTAL EMSCO DB-550 Duplex Mud Pump, S/N-551, 550 HP, MATTCO
Forged Steel Fluid End w/Quick-Change Caps, CONTINENTAL EMSCO PD-53
Pulsation Dampener, S/N-413, CONTINENTAL EMSCO 2" Shear Relief Valve,
Rod Cooling Pump, 3000 PSI Pressure Gauge, Belt Drive Assembly,
Skidded & Master Skidded w/Engine

PUMP POWER

CAT D379 Diesel Engine, S/N-68B07032, Air Starter, Radiator, Gauges,
Air Clutch

ROTATING EQUIPMENT

Exh B-17
69
RIG NO. 7

CONTINENTAL EMSCO 27-1/2 27-1/2" x 53-1/4" Rotary Table,
S/N-MDLDL2750, Split Master Bushing

NATIONAL N-69 400-Ton Swivel

4-1/4" x 41'L Square Kelly w/Shuck

VARCO Type HD Kelly Drive Bushing, Square Drive.

Upper & Lower Kelly Valves

TRAVELING EQUIPMENT

IDEAL Approximately 300-Ton Block w/(5) 46" Sheaves, 1-1/4" Line w/BJ
4300 300-Ton Hook

(2) 3-3/4" x 120" Elevator Links

WELL CONTROL EQUIPMENT

HYDRIL GK 11" 5000 PSI Annular Blowout Preventer w/Studded Top,
Flanged Bottom

NL SHAFFER LWS 11" 5000 PSI Double Blowout Preventer w/4-1/2" Pipe &
Blind Rams, Flanged Top & Bottom, (4) 4- 1/16" 5000 PSI Flanged
Outlets

CAMERON 24"H x 11"ID 5000 PSI Drilling Spool w/(2) 4-1/16" Flanged
Outlets, W-K-M 4-1/16" 5000 PSI Gate Valve, BARTON 4-1/16" 5000 PSI
Gate Valve, (7) Blowout Preventer Hand Wheels w/Shafts, Hydraulic Gate
Valve

(2) 20"H x 11"ID, (2) 12"H x 11"ID & (1) 8"H x 11"ID 3000 PSI Spacer
Spools

KOOMEY Type 80 090-11SX 5-Station Closing Unit, S/N-1570, Triplex
Hydraulic Pump p/b 15 HP Electric Motor, (2) Pneumatic Pumps,
Separator/Accumulators, Hydraulic Reservoir, Skidded w/Lifting Frame

KOOMEY GARC-5 Remote Control Unit, S/N-5048

CEDCO LDW-20 Wireline Measuring Unit, S/N-613, Mounted w/Closing Unit

5000 PSI Blowout Preventer Choke Manifold w/CAMERON 4-1/16" 5000 PSI
Gate Valve, (2) CAMERON 2-1/16" 5000 PSI Gate Valves, (2) W-K-M
2-1/16" 5000 PSI Gate Valves, (1) 2" Gate Valve, 4-1/16" x 2-1/16"
5000 PSI 4-Way Flanged Cross, (1) 2-1/16" Manual Adjustable Choke, All
Mounted on Adjustable-Height Skid

RIG HOUSES

10'W x 24'L Doghouse, Round Top, Knowledge Box, (5) Lockers, Bench
Storage, Lights, Skidded

7'5"W x 20'L Change House w/Round Top, (16) Lockers, Bench Storage,
Cabinets, Top-Mounted Doghouse Supports, Fluorescent Lights, Heater,
Skidded

7'7"W x 30'L Mud House w/Round Top, Mud Hopper, Fluorescent Lights,
Skidded

SATELLITE Automatic Driller, S/N-N/A

TETON HOMES 10'W x 40'L Toolpusher's House, Furnished, Skidded

Exh B-18
70
RIG NO. 7

GENERATORS/UTILITY HOUSE

(2) 135 KW AC Generators, S/Ns-N/A, Each p/b CAT 3306 Diesel
Engine, S/Ns-66D16919 & 66D14473, (1) w/Air & (1) w/Electric
Starter, Radiator, Gauges, Skidded

QUINCY 350 Air Compressor p/b 10 HP Electric Motor

SQUARE D Electric Control Panel

10'W x 33'L Crimped-Steel Utility House w/Round Top, Fluorescent
Lights

MUD SYSTEM

7'6"W x 6'H x 32'L 259-Barrel Premix Tank w/Round Bottom,
Single-Compartment, Internal Plumbing, Side-Mounted Walkways, Skidded

7'6"W x 6'H x 36'L Crimped-Steel 292-Barrel Mud Suction Tank w/(2)
Compartments, Round Bottom, Internal Plumbing, Top & Side-Mounted
Walkways, Stairs, Safety Rails, Skidded

7'6"W x 6'H x 36'L Crimped-Steel 292-Barrel Mud Volume Tank w/(2)
Compartments, Round Bottom, Internal Plumbing, Top & Side-Mounted
Walkways, Stairs, Safety Rails, Skidded

7'6"W x 6'H x 36'L Crimped-Steel 292-Barrel Mud Shaker Tank w/(2)
Compartments, Round Bottom, Internal Plumbing, Top & Side-Mounted
Walkways, Stairs, Safety Rails, Skidded

MCM 6" x 8" Centrifugal Pump p/b CAT D333 Diesel Engine w/Air Starter,
Radiator, Gauges, Skidded

30"Dia x 10'L Atmospheric Degasser, On Stand w/(2) 2" Gate Valves

WATER/FUEL TANKS

(2) J & J STEEL & SUPPLY CO. 10'6"Dia x 32'L 500-Barrel Water
Tanks, Skidded

MISSION 3" x 4" Centrifugal Pump p.b 25 HP Electric Motor

7'4"Dia x 8'L Potable Water Tank, Skidded

48"Dia x 12'L 4-Compartment Lubester, Skidded

HANDLING TOOLS

(2) WOOLLEY Type C Tongs w/Heads

WOOLLEY 4-1/2"BN 225-Ton Center Latch Drill Pipe Elevators

WEB WILSON 8" Side Latch Drill Collar Elevators

WOOLLEY Center Latch Drill Collar Elevators

WOOLLEY 4-1/2" Drill Pipe Slips

11-Segment Drill Collar Slips

Exh B-19
71
RIG NO. 7

10-Segment Drill Collar Slips

Drill Collar Safety Clamp

(8) Drill Collar Lift Nubbins

INGERSOLL-RAND HU 4000# Capacity Air Hoist, S/N-N/A

4-1/2" Mud Bucket

AUXILIARY EQUIPMENT

3-1/2"ID x 55'L Rotary Hose

(2) 3-1/2"ID x 15'L Vibrator Hoses, 3-1/2"ID x 11'L Vibrator Hose

40"H x 6'8"W x 56'L 2-Section Catwalk w/Steel Deck

2 Sets (4) 42"H x 28'L Triangular Pipe Racks

(7) 36"H x 8'W x 37'L Pipe Tubs

6'W x 2'H x 8'L Junk Box

(20) Miscellaneous Drill Collar Subs

Rathole & Mousehole

Type D Mud Gauge, S/N-162301

Fluorescent & Mercury-Vapor Rig Lights w/Wiring

Approximately 3500' of 1-1/4" Drill Line w/Wood Spool, Stand

QUINCY 350 Air Compressor p/b LISTER ST2A Diesel Engine w/Electric
Starter, Air Receiver Tank

Miscellaneous Spare Parts, Hand Tools, Valves, Fire Extinguishers, Etc

TOTAL RIG NO. 7 W/O TUBULARS:

DRILL PIPE

1550' (50 Joints) 4-1/2", Grade X-95, 22.82#, Range 2 Drill Pipe
w/4-1/2"XH Tool Joints, 6-1/8"OD to 6-1/4"OD

Approximately 2170' (70 Joints) 4-1/2", Grade E, 20.00#, Range 2 Drill
Pipe w/4-1/2"XH Tool Joints, 5-7/8"OD to 6"OD, PC

Approximately 9920' (320 Joints) 4-1/2", Grade E, 16.60#, Range 2
Drill Pipe w/4-1/2"XH Tool Joints, 6-1/4"OD, PC

Approximately 620' (20 Joints) 4-1/2", Grade S-135, 16.60#, Range 2
Drill Pipe w/4-1/2"XH Tool Joints, 6- 1/4"OD, PC

Exh B-20
72
RIG NO. 7

Approximately 1860' (60 Joints) 4-1/2", Grade X-95, 16.60#, Range 2
Drill Pipe w/4-1/2"XH Tool Joints, 6- 1/4"OD, PC

DRILL COLLARS

(26) 5-7/8"OD to 6-1/4"OD x Approximately 29.50'L Drill Collars
w/4-1/2"XH Connections @ $200.00/Each

(20) 7-1/2"OD to 7-7/8"OD x Approximately 29.50'L Drill Collars
w/6-5/8"H-90 Connections @ $800.00/Each

TOTAL RIG NO. 7 W/TUBULARS:

Exh B-21
73
RIG NO. 10

RIG NO. 10

DRAWWORKS

MID-CONTINENT U-36A Single Drum Drawworks, S/N-137, 600 HP, LEBUS
Grooved f/1-1/8" Line, FOSTER Makeup & Breakout Catheads, Overrunning
Clutch, Air Driller's Console, Crown-O-Matic

COMPOUND

MID-CONTINENT 2-Engine Compound, S/N-N/A, QUINCY 390 Air Compressor,
S/N-N/A, Covered Skid

BRAKE

PARMAC V-80 Double Hydromatic Brake, S/N-56607

ENGINES

(2) CAT D353 410 HP Diesel Engines, S/Ns-46B09311 & 46B09465,
w/Air Starters, Radiators, Gauges, TWIN DISC F-10030-80-3
Torque Converters, S/Ns-N/A & 819472

MAST

LEE C. MOORE 127'H Cantilever Mast, S/N-T2884, 450,000# GNC, Pin-Type,
Crown Block w/(4) Sheaves, Fastline Sheave, 1-1/8" Line, 4" Standpipe,
Crown Safety Platform, Racking Board, Tong Counterweights, Ladder,
Derrick Climber, Geronimo, Boom, Mast Stand, Standpipe Manifold w/4" &
2" Gate Valves

SUBSTRUCTURE

LEE C. MOORE 14'H x 19'W x 45'L Box-On-Box Substructure w/Rotary
Beams, V-Door Ramp, Air Volume Tank, (4) Stairs, Safety Rails,
Deadline Anchor, Steel Windwalls w/Windwall Skid

PUMP

MID-CONTINENT DB-550 Duplex Mud Pump, S/N-N/A, 550 HP, 5-1/2" x 16",
MATTCO Forged Steel Fluid End w/Quick- Change Caps, HYDRIL K-20-3000
Pulsation Dampener, S/N-31042, CONTINENTAL EMSCO Shear Relief Valve,
Rod Cooling Pump, Drive Assembly, Skidded, Master Skidded w/Engine
(Note: Located in Hobbs Yard)

PUMP POWER

CAT D379 TC Diesel Engine, S/N-68B4650, Air Starter, Radiator, Gauges,
Air Clutch (Engine In Main Yard)

PUMP

MID-CONTINENT DA-500 Duplex Mud Pump, S/N-N/A, Forged Steel Fluid End
w/Quick-Change Caps, CONTINENTAL EMSCO PD-53 Pulsation Dampener, Rod
Cooling Pump, TOTCO 3000 PSI Pressure Gauge, Drive Assembly, Skidded &
Master Skidded

Exh B-22
74
RIG NO. 10

PUMP POWER

CAT D353 Diesel Engine, S/N-46B8397, Air Starter, Radiator, Gauges,
Air Clutch

ROTATING EQUIPMENT

OILWELL A20-1/2 20-1/2" x 53-1/4" Rotary Table, S/N-N/A, Split Master
Bushing

NATIONAL N-47 200-Ton Swivel, S/N-N/A

4-1/4 x 40'L Square Kelly

VARCO HD Kelly Drive Bushing, Square Drive

Upper Kelly Valve

Lower Kelly Valve

Inside Blowout Preventer

TRAVELING EQUIPMENT

SOWA 300-Ton Block/Hook Combination, S/N-N/A, w/(5) Sheaves, 1-1/8"
Line

3-1/2" x 120" Elevator Links

WELL CONTROL EQUIPMENT

NL SHAFFER SPH 11" 5000 PSI Annular Blowout Preventer, S/N-N/A,
w/Studded Top & Flanged Bottom

NL SHAFFER Type LWS 11" 5000 PSI Double Blowout Preventer w/4-1/2"
Pipe & Blind Rams

24"H x 11"ID 5000 PSI Drilling Spool w/(2) 4-1/16" Outlets w/(1) 2"
3000 PSI Gate Valve

KOOMEY ET-10160-3B 6-Station Closing Unit, S/N-5048, w/244-Gallon
Hydraulic Fluid Reservoir, (2) Air-Operated Hydraulic Pumps, Triplex
Pump p/b Electric Motor, (2) 80-Gallon Spherical Accumulators, Skidded

KOOMEY GARC-5 5-Station Remote Closing Unit, S/N-5048, Mounted on
Doghouse Porch

(2) 6"H x 5'W x 21'L Suitcases w/Enclosed Hydraulic Lines

CAMERON/OTECO 3000 PSI Blowout Preventer Choke Manifold w/4-1/16" x
2-1/16" Cross, 4-1/16" Gate Valve, (4) 2- 1/16" Gate Valves, (2)
Adjustable Chokes, On Adjustable Support, Buffer Chamber, On Separate
Adjustable Support

RIG HOUSES

TETON HOMES 10'W x 40'L Toolpusher's House, Fully Furnished, Skidded

10'W x 24'L Doghouse w/Round Top, Knowledge Box, (6) Lockers, Bench
Storage, Cabinets, Parts Bins, Fluorescent Lights, Heater, Skidded

SATELLITE Apollo Automatic Driller

Exh B-23
75
RIG NO. 10

8'W x 30'L Mud House w/Round Top, 5'L Pump Parts Room, (3) Triangular
Supports, Fluorescent Lights, Skidded

GENERATORS/UTILITY HOUSE

(2) 135 KW AC Generators, S/Ns-5CA05776 & 5CA05775, Each p/b CAT
3306 Diesel Engine, Each w/Air Starter, Radiator, Gauges
(Note: Located in Hobbs Yard)

QUINCY 350 Air Compressor, S/N-150088, w/BALDOR Electric Motor, Air
Receiver Tank

SQUARE D & SYLVANIA Electric Controls

All Above Mounted in 11'6"W x 38'L Utility/Change House w/Round Top,
(13) Lockers, Fluorescent Lights, Heater, Skidded

MUD SYSTEM

7'6"W x 6'H x 36'L Mud Suction Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

REED AMERICAN 6" x 8" Centrifugal Pump, S/N-N/A, p/b 100 HP Electric
Motor

7'6"W x 6'H x 36'L Mud Volume Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

7'6"W x 5'H x 30'L Mud Mixing Tank w/Single-Compartment, Round Bottom,
Top & Side-Mounted Walkways, Stairs, Safety Rails, Skidded

7'6"W x 6'H x 36'L Mud Shaker Tank w/(2) Compartments, Round Bottom,
Internal Plumbing, Top & Side-Mounted Walkways, Stairs, Safety Rails,
Skidded

WATER TANKS

(2) 10'6"Dia x 32'L Water Tanks, Skidded, (1) w/MISSION 2" x 3"
Centrifugal Pump, Electric Motor

4'Dia x 13'L 4-Compartment Lubester, Skidded

HANDLING TOOLS

WOOLLEY Type B Tongs w/Heads

WOOLLEY 4-1/2"BN Drill Pipe Elevators

WOOLLEY 8"SS Center Latch Elevators

WOOLLEY 7"SS Center Latch Elevators

WOOLLEY 4-1/2" Drill Pipe Slips

WOOLLEY 10-Segment Drill Collar Slips

WOOLLEY 11-Segment Drill Collar Slips

Exh B-24
76
RIG NO. 10

Drill Collar Safety Clamp

(19) Drill Collar Lift Nubbins

INGERSOLL-RAND HU40 Air Hoist, S/N-RFM89763

Mud Bucket

AUXILIARY EQUIPMENT

TOTCO 50 400,000# Capacity Weight Indicator w/Pump Pressure, Tong Line
Pull & Rotary Torque Gauges

TOTCO 4 Mud Gauge

3-1/2"ID x 55'L Rotary Hose

10"ID x 5'L Suction Hose

8"ID x 5'L Suction Hose

(2) 3"ID x 12'L Vibrator Hoses

42"H x 5'W x 56'L 2-Section Catwalk w/Steel Deck

24"H x 7'W x 12'L Junk Box

(5) 33"H to 36"H x 7'W to 7'6"W x 34'L Pipe Tubs

3 Sets (6) 42"H x 28'L Triangular Pipe Racks

CEDCO Hydraulic Measuring Device, Approximately 10,000' of .072"
Wireline (At Yard)

(13) Miscellaneous Drill Collar Subs

Rathole & Mousehole

Fluorescent & Mercury-Vapor Rig Lights w/Wiring

Approximately 5000' of 1-1/8" Drill Line w/Spool, Stand

Miscellaneous Spare Parts, Hand Tools, Valves, Fire Extinguishers, Etc

TOTAL RIG NO. 10 W/O TUBULARS:

DRILL PIPE

Approximately 7750' (250 Jts) 4-1/2", Grade E, 16.60#, Range 2 Drill
Pipe w/4-1/2"XH Tool Joints, 5-3/4"OD to 6"OD

DRILL COLLARS

(35) 6"OD x Approximately 29.00'L Drill Collars w/4-1/2"H-90
Connections

Exh B-25
77
RIG NO. 10

6-1/2"OD x Approximately 29.50'L Drill Collar w/5"H-90 Connections

(20) 7-1/2"OD to 7-3/4"OD x Approximately 29.50'L Drill Collars
w/6-5/8" H-90 Connections

TOTAL RIG NO. 10 W/TUBULARS:

Exh B-26
78
RELATED YARD EQUIPMENT

RELATED YARD EQUIPMENT

BRAKES

PARMAC 342 34" Double Hydromatic Brake, S/N-51765

(3) PARKERSBURG 40SR Hydromatic Brakes, S/Ns-P13958, N/A & N/A

(2) PARKERSBURG 46" Double Hydromatic Brakes, S/Ns-35464 & 179

ENGINES ON YARD

CAT D353 Diesel Engine, S/N-N/A, w/Radiator & Gauges (Rebuilt)

CAT D379 Diesel Engine, S/N-N/A, w//Radiator & Gauges (Rebuilt)

CAT D379 Diesel Engine, S/N-N/A, w/Radiator & Gauges (Rebuilt)

CAT D379 Diesel Engine, S/N-N/A, Air Starter, Radiator, Gauges (Being
Rebuilt)

MUD PUMPS/PUMP PARTS

(2) CONTINENTAL EMSCO DB-700 Duplex Mud Pumps, S/Ns-185 & 248,
Each 700 HP, 7-1/2" x 16", Cast Steel Fluid End w/Quick-Change
Caps, HYDRIL K-20-3000 Pulsation Dampener, Rod Cooling Pump,
Bull Wheel, Compound Driven, Skidded

MID-CONTINENT DB-500 Duplex Mud Pump, S/N-57 (Gear End Only)

(2) CONTINENTAL EMSCO DB-550 Duplex Mud Pumps, Skidded (Gear End &
1/2 of Fluid End Only)

EMSCO D-700 Duplex Mud Pump, S/N-104, Skidded & Master Skidded (Gear
End Only)

(4) MATTCO Forged Steel Fluid Ends

Reconditioned Forced Steel Fluid End

(4) Cast Steel Fluid Ends

CONTINENTAL EMSCO PD-53 Pulsation Dampener, S/N-339, w/DEMCO 2" Shear
Relief Valve, Pressure Gauge

CONTINENTAL EMSCO PD-53 Pulsation Dampener, HYDRIL K-20 Pulsation
Dampener

MISSION 2" X 3" Centrifugal Pump

MAST/SUBSTRUCTURE (WEST YARD)

LEE C. MOORE 18'W x 131'H Mast, S/N-N/A. Pin-Type, Crown Block w/(5)
42" Sheaves, Safety Platform. Grooved f/1-1/4" Line, Tong
Counterweights, Racking Board

Exh B-27
79
RELATED YARD EQUIPMENT

10'H x 22'W x 48'L Substructure w/Rotary Beams, Spreader Beams, 5'6"W
x 8'H x 5'6"L Parts House, 18"Dia x 20'L Air Volume Tank, (2) 36'W x
48'L Side-Mounted Folding Walkways, Skidded

ROTATING EQUIPMENT

(2) 5-1/4" x 40'L Hex Kellys

4-1/4' x 40'L Square Kelly (Unused)

(8) 4-1/4" x 40'L Square Kellys

(3) 3-1/2 x 40'L Square Kellys

4-1/4" x 40'L Square Kelly

VARCO 4KRP Pin-Type Kelly Drive Bushing

(2) OILWELL PC-300 Swivels

TRAVELING EQUIPMENT

OILWELL Approximately 500-Ton Traveling Block w/(6) 48" Sheaves

EMSCO 300-Ton Traveling Block w/(5) Sheaves

OILWELL 300 Traveling, Block w/(5) 42" Sheaves

IDEAL Approximately 400-Ton Traveling Block w/(5) 48" Sheaves

OILWELL 66 Block w/BJ Dynaplex 250-Ton Hook

BJ Dynaplex 5500 500-Ton Hook, S/N-675

BJ 4300 300-Ton Hook

BJ 4200 200-Ton Hook

(2) 3" x 132" Elevator Links

(2) 2-1/2" x 132" Elevator Links

(2) 3" x 96" Elevator Links

(2) 3-3/4" x 144" Elevator Links

WELL CONTROL EQUIPMENT

SHAFFER SPH 11" 5000 PSI Annular Blowout Preventer

NL SHAFFER SL 13-5/8" Double Blowout Preventer, S/N-D4687, w/Studded
Top & Bottom, (4) 4-1/16" 5000 PSI Flanged Outlets, 23"H x 13-5/8"ID
5000 PSI Drilling Spool w/(2) 4-1/16" 5000 PSI Flanged Outlets

Exh B-28
80
RELATED YARD EQUIPMENT

NL SHAFFER LWS 11" Double Blowout Preventer w/Studded Top & Bottom,
(4) 4-1/16" 3000 PSI Flanged Outlets, 19- 1/2"H x 10"ID 3000 PSI
Drilling, Spool w/(2) 4-1/16" 3000 PSI Flanged Outlets

SHAFFER LWS 11" 5000 PSI Double Blowout Preventer w/4-1/16" Outlets

SHAFFER Type B 11" 3000 PSI Double Blowout Preventer w/Studded Top &
Bottom

(2) CAMERON QRC 11" 3000 PSI Single Blowout Preventers

SHAFFER Type B 13-5/8" 3000 PSI Double Blowout Preventer w/4-1/2" Pipe
& Blind Rams, 12" 3000 PSI Spool, 4- 1/16" & 2-1/16" Outlets, 12"Dia x
35'L 3000 PSI Spool

SHAFFER 11" 5000 PSI Annular Blowout Preventer, Studded Top, Flanged
Bottom

SHAFFER LWS 11" 3000 PSI Single Blowout Preventer

HYDRIL GK 13-5/8" 3000 PSI Annular Blowout Preventer, Studded Top,
Flanged Bottom

SHAFFER Type B 13-5/8" 3000 PSI Double Blowout Preventer w/4-1/2" Pipe
& Blind Rams, 12"Dia x 62"L Spool, 4- 1/16" & 2-1/16" Flanged Outlets

PAYNE 4-Station Closing Unit w/80-Gallon Spherical Accumulator
(Incomplete), PAYNE 4-Station Closing Unit w/(2) 40-Gallon Spherical
Accumulators

VETCO 10,000 PSI Choke Manifold w/5-Way Cross, (1) 4-1/16" & (5)
2-1/16" Gate Valves, Adjustable Choke, Buffer Chamber, Mounted on
Adjustable Skid

(3) 4" 5000 PSI Hydraulic Gate Valves (2 Rebuilt, In Shop)

(2) CAMERON Type F 4-1/16" Gate Valves (In Shop)

SHAFFER 4" Gate Valve (In Shop)

(4) Lower Kelly Valves (In Shop)

RIG HOUSES

TETON HOMES 10'W x 40'L Toolpusher's House, Furnished, Skidded

7'6"W x 37'L Generator/Parts House w/Round Top, (4) 1" Hydraulic Flex
Hoses, Skidded (Storage)

7'W x 26'L Change House w/Round Top, (16) Lockers. Skidded

7'W x 15'L Doghouse w/Round Top, Skidded (Storage)

7'W x 12'L Doghouse w/V-Top, Skidded (Storage)

7'6"W x 17'L Welded-Steel House w/Round Top, Skidded, 7'W x 18'L
Welded Steel House w/Round Top, Skidded, 7'W x 12'L Welded Steel House
w/Flat Top, Skidded (Parts Storage)

AIR COMPRESSORS (MAIN YARD)

SULLAIR 185 Air Compressor, S/N-004119146, p/b JOHN DEERE Diesel
Engine, On Single Axle Trailer

Exh B-29
81
RELATED YARD EQUIPMENT

INGERSOLL-RAND Air Compressor, S/N-N/A, p/b 4-Cylinder Diesel Engine,
On Single Axle Trailer

(5) QUIINCY 325 Air Compressors

(2) QUINCY 390 Air Compressors

QUINCY 350 Air Compressor

QUINCY 340 Air Compressor

DRIVE BUSHINGS (MAIN YARD)

VARCO 4KRP Hex Kelly Drive Bushing

(2) VARCO 4KRBS Square Kelly Drive Bushings

VARCO 4KRS Hex Kelly Drive Bushing

MISCELLANEOUS EQUIPMENT

(4) Sets of Steel Windwalls w/Windwall Boxes

7550' of 1-1/4" Drill Line w/Spool (Unused)

(6) Bull\wheels

(8) Assorted & Partial Crown Blocks

(9) 7'W x 36"H x 35'L Pipe Tubs

Approximately (300) Miscellaneous Drill Collar Subs

Approximately (100) Miscellaneous Lift Nubbins

Flanges, Tees, Ells, Spools, Adapters, Mud Buckets

7'6"W x 3'H x 12'L Junk Box w/Storage Boxes, Skidded

10'H x 8'W x 40'L Truck Ramp w/Wood Deck, 15'H x 8'W x 10'L Extension

(2) 3-Compartment Lubesters, Skidded

(4) Approximately 8' x 8' Steel-Framed Wood Rig Mats

(3) LIGHTNIN Mud Agitators p/b 5 HP Electric Motors

9 Sets (18) 42"H x 28'L Triangular Pipe Racks

3 Sets (6) 42"H x 28'L T-Type Pipe Racks

(4) Miscellaneous Lift Frames

Exh B-30
82
RELATED YARD EQUIPMENT

HANDLING TOOLS

(8) WOOLLEY Type B Tongs w/Heads

BJ Type G 5"BN Drill Pipe Elevators

WOOLLEY 5"BN 225-Ton Drill Pipe Elevators

(3) WOOLEY 4-1/2"BN 225-Ton Drill Pipe Elevators

BJ 3-1/2"BN Drill Pipe Elevators

BJ MGG 4-1/2"BN Drill Pipe Elevators

WEB WILSON 7-1/2" Center Latch Drill Collar Elevators

WTM 4-1/2" 225-Ton Center Latch Drill Pipe Elevators

WILSON 8" Side Door Elevators

WILSON 9" Side Door Elevators

(4) Drill Collar Slips

FORKLIFT

TROJAN 2000 Model 1900 Articulating Forklift, S/N-192383, p/b DETROIT
4-Cylinder Engine, 6'L Forks, 17.50x25 L- 3) Tires

WELDER

LINCOLN SA-200 Arc Welder, S/N-775588, p/b RED SEAL 4-Cylinder Gas
Engine, Mounted on Tandem Axle Trailer w/Cutting Torch

TOTAL RELATED YARD EQUIPMENT:

Exh B-31
83
TUBULAR GOODS (Hobbs, New Mexico)

TUBULAR GOODS (HOBBS, NEW MEXICO)

DRILL PIPE

2170' (70 Joints) 4-1/2", Grade G, 16.60#, Range 2 Drill Pipe
w/4-1/2"XH, BN, HUGHES Tool Joints, 6-1/4"OD

1767' (57 Joints) 4-1/2", Grade E, 16.60#, Range 2 Drill Pipe
w/4-1/2"XH, BN HB Tool Joints, 5-15/16"OD to 6- 3/16"OD, Some PC
w/Double White Band

1674' (54 Joints) 4-1/2" Grade E, 16.60#, Range 2 Drill Pipe
w/4-1/2"XH, BN, HB Tool Joints, 5-7/8" OD to 6"OD, PC w/Double White
Band

899' (29 Joints) 4-1/2", Grade X-95, 16.60#, Range 2 Drill Pipe
w/4-1/2"XH, BN, HB Tool Joints, 6"OD to 6- 1/8"OD, PC

3689' (119 Joints) 4-1/2", Grade E, 16.60#, Range 2 Drill Pipe
w/4-1/2"XH, BN, Some HB Tool Joints, 5-3/4"OD to 6-1/8"OD, PC w/Yellow
Band

2821' (91 Joints), 4-1/2", Grade G, 20.00#, Range 2 Drill Pipe
w/4-1/2"XH, BN, Most HB Tool Joints, Some PC

DRILL COLLARS (ALL LENGTHS ARE APPROXIMATE)

(5) 8"OD x 31'L Drill Collars w/6-5/8"H-90 Connections

(3) 8-7/8"OD x 28'L Drill Collars w/7-5/8"Reg Connections

6-3/4"OD x 29'L Drill Collar w/4-1/2"XH Connections

(42) 5-13/16"OD to 6-1/16"OD x 29.50'L Drill Collars w/4-1/2"H-90
Connections

(9) 6-1/2"OD x 31'L Drill Collars w/4-1/2"XH Connections

(52) 5-7/8" to 6-1/16"OD x 28'L Drill Collars w/4-1/2"H-90
Connections

(28) 5-11/16"OD to 5-7/8"OD x 29'L Drill Collars w/4-1/2"XH
Connections

(2) 6-3/4"OD x 30'L Drill Collars w/5"H-90 Connections

(5) 7-15/16"OD x 29'L Drill Collars w/6-5/8"H-90 Connections

DRILL COLLARS (AT SHOP)

(18) 5-13/16"OD to 6-3/16"OD x 28'L Drill Collars w/4-1/2"XH
Connections

(19) 7-3/4"OD x 29'L Drill Collars w/6-5/8"H-90 Connections

(13) 5-7/8"OD x 29'L Drill Collars w/4-1/2"H-90 Connections

(15) 5-13/16"OD x 29'L Drill Collars w/4"H-90 Connections

Exh B-32
84
TUBULAR GOODS (Hobbs, New Mexico)

TOTAL TUBULAR GOODS:

B. VEHICLES
--------

1. 1996 Ford F350 Crewcab (Z*DRL 1)
ID No. 1FTJW35F6TEA02425
1997 Sticker #079565 Billy

2. 1997 Ford X150 Pickup (Z*DRL 6)
ID No. 1FTDX17W9VNB60627
1997 Sticker #12077171

3. 1991 Chev Pickup (584 HGH)
ID No. 2GCEC19K2M1166330
1997 Sticker #079574 Yard

4. 1995 Ford F150 Supercab Pickup (Z*DRL 3)
ID No. 1FTEX15N5SKA93035
1997 Sticker #079564 George

5. 1995 Chev GM4 Pickup (Z*DRL 4)
ID No. 2GCEC19H8S1172828
1997 Sticker #079566 Wesley

6. 1984 Ford F600 (*DRL21)
ID No. FDNF60H1EVA34290
1997 Sticker #079583 Shop

7. 1996 Ford F150 Pickup (Z*DRL 2)
ID No. 1FTEX15N5TKA25223
1997 Sticker #079582 Ricky

8. 1997 Ford F150 Pickup (969DPL)
ID No. 1FTDX1768VNB03335
1997 Sticker #079580 Howard

9. 1994 Chev Pickup (447GAW)
ID No. 2GCEC19ZOR1272389
1997 Stick No. 079571 Ty

10. 1989 Ford Truck - Welding (037JGR)
ID No. 1FDKF37G6KKA14113
1997 Sticker No. 079568 Carl

11. 1985 International Truck NO.102
ID No. 2HSTGJUT7FCA16310
1997 Sticker No. CC04966 (IRA1822)

12. 1995 International Truck NO. 105
ID No. 2HSFMAHR1SC027573
1997 Sticker No. CC04963

Exh B-33
85

13. 1997 1997 Ford Pickup (368JWR)
ID No. 1FTJW35F4VEB17687
1997 Sticker No. 12078807 Shirrel

C. OFFICE EQUIPMENT
----------------

All office equipment owned by ZIADRIL, Inc.

Exh B-34
86
APPENDIX II
TO
BILL OF SALE AND ASSIGNMENT
FROM
ZIADRIL, INC.
TO
PATTERSON DRILLING COMPANY
(List of Drilling Contracts and Other Agreements Assigned)

D. DRILLING CONTRACTS.

1. Drilling Contract dated March 12, 1997, between Penwell
Energy, Inc. and ZIADRIL, Inc.

2. Drilling Contract dated March 25, 1997, between Chesapeake
Operating, Inc. and ZIADRIL, Inc.

3. Drilling Contract dated March 26, 1997, between Penwell
Energy, Inc. and ZIADRIL, Inc.

4. Drilling Contract dated February 24, 1997, between John L. Fox
and ZIADRIL, Inc.

5. Drilling Contract dated February 28, 1997, between Amerlind
Oil Company, Ltd. and ZIADRIL, Inc.

E. OTHER AGREEMENTS.

1. Lease Agreement dated August 1, 1990, between ZIADRIL, Inc. as
lessor, and Wilson Industries, Inc. as lessee.

2. Commercial Lease and Deposit Receipt dated August 23, 1995,
from Bo Blackwood, agent for Crystal Clear Water Sales and
Services to ZIADRIL, Inc.

3. 1st Equity Realtors, Inc. Property Leasing Agreement dated
August 25, 1995, between ZIADRIL, Inc. and First Equity
Realtors, Inc.

Exh B-35
87
EXHIBIT C(I)

WARRANTY DEED
[West County Road Property]

ZIADRIL, INC. f/k/a MORANCO DRILLING, INC., a New Mexico Corporation,
for consideration paid, grants to PATTERSON DRILLING COMPANY, a Delaware
corporation, whose address is Post Office Drawer 1416, Snyder, Texas 79550, the
following described real estate situated in Lea County, New Mexico to wit:

THE SURFACE ONLY TO:

A tract of land located in the Northwest Quarter of Section
32, Township 18 South, Range 38 East, N.M.P.M., Lea County, New
Mexico, and more particularly described as follows:

Beginning at a point located in the East right-of-way line of
county highway No. C-66 (West County By- Pass road) said point being
located North 89 degrees 47'30" East 1078.6 feet and South
0 degrees 44'30" East 1162.0 feet from the Northwest corner of said
Section 32; thence North 89 degrees 47'30" East 660.0 feet; thence
South 0 degrees 44'30" East 495.0 feet; thence South 89 degrees 47'30"
West 660.0 feet to the East right-of-way line of said county highway
No. C-66; thence North 0 degrees 44'30" West along the East
right-of-way line of said county highway No. C-66 495.0 feet to the
point of beginning, containing 7.5 acres, more or less, excepting,
however, all minerals therein and thereunder.

with warranty covenants.

WITNESS my hand this _______ day of April, 1997.

ZIADRIL, INC. f/k/a MORANCO DRILLING,
INC., a New Mexico Corporation

By:
-------------------------------------
JOE SMITH, President

STATE OF NEW MEXICO )
) ss
COUNTY OF LEA )

On this _____ day of April, 1997, before me personally appeared JOE
SMITH, as President of ZIADRIL, INC. f/k/a MORANCO DRILLING, INC., a New Mexico
corporation, to me known to be the person described in and who executed the
foregoing instrument, and acknowledged that he executed the same as his free
act and deed.

WITNESS my hand and seal the day and year last above written.

----------------------------------------
NOTARY PUBLIC

My Commission Expires:

================================================================================
STATE OF NEW MEXICO )
) ss.
COUNTY OF LEA )

I hereby certify that this instrument was filed for record on the
_____ day of __________, 1997, at _____ o'clock __.m. and duly recorded in Book
_____ Page _____ of the deed Records of said County.

----------------------------------------
County Clerk

By:
-------------------------------------
(Deputy Clerk)

RETURN TO: TOMMY D. PARKER
POST OFFICE BOX 1094
HOBBS, NEW MEXICO 88241-1094
88
EXHIBIT C(II)

WARRANTY DEED
[Marland Street Property]

THE SURFACE ONLY TO:

Parcel 1: The North 26 feet of Lot Twenty (20), Lots Twenty-One
(21), Twenty-two (22) and Twenty-Three (23), Block One (1), Byers
Heights Addition to the City of Hobbs, Lea County, New Mexico.

Parcel 2: A tract of land located in the Northeast Quarter
(NE/4) of Section 4, Township 19 South, Range 38 East, N.M.P.M., Lea
County, New Mexico, more particularly described as follows:

Beginning at a point which lies West 430 feet and South
0 degrees 4' West 50 feet from the Northeast corner of said
Section 4; Thence West 670 feet to the Northwest corner of
said tract; Thence South 0 degrees 4' West 520 feet to the
Southwest corner of this tract; Thence East 670 feet to the
Southeast corner of this tract; Thence North 0 degrees 4' East
520 feet to the point of beginning.

with warranty covenants.

WITNESS my hand this _______ day of April, 1997.

ZIADRIL, INC. f/k/a MORANCO DRILLING,
INC., a New Mexico Corporation

By:
-------------------------------------
JOE SMITH, President

STATE OF NEW MEXICO )
) ss
COUNTY OF LEA )

WITNESS my hand and seal the day and year last above written.

----------------------------------------
NOTARY PUBLIC
My Commission Expires:

================================================================================
STATE OF NEW MEXICO )
) ss.
COUNTY OF LEA )

I hereby certify that this instrument was filed for record on the
_____ day of __________, 1997, at _____ o'clock __.m. and duly recorded in Book
_____ Page _____ of the deed Records of said County.

----------------------------------------
County Clerk

By:
-------------------------------------
(Deputy Clerk)
RETURN TO: TOMMY D. PARKER
POST OFFICE BOX 1094
HOBBS NEW MEXICO 88241-1094