SETTLEMENT AGREEMENT AND MUTUAL RELEASE

         This Settlement Agreement and Mutual Release ("Agreement") is made and
entered into as of this 19th day of September, 2005, by and among Chevron
Environmental Management Company, Chevron Environmental Services Company, and
Texaco Inc. (collectively, "Plaintiffs"), on the one hand, and Castle Energy
Corporation ("Castle"), Indian Refining I Limited Partnership (f/k/a Indian
Refining Limited Partnership), Indian Refining & Marketing I, Inc., (f/k/a
Indian Refining & Marketing, Inc.), and William S. Sudhaus, on the other hand
(collectively "Defendants").

         WHEREAS, on or about August 13, 2002, Plaintiffs filed their Complaint
against Defendants in the United States District Court for the Southern District
of Illinois, Cause No. 02-4162 JPG, alleging that, based on a number of
theories, Defendants were liable for costs associated with environmental
contamination at the former Indian Refinery located in Lawrenceville, Illinois
(the "Lawsuit"); and

         WHEREAS, Defendants have denied any and all liability for the damages
alleged in Plaintiffs' Lawsuit; and

         WHEREAS, Plaintiffs and Defendants now desire to resolve amicably the
disputes and disagreements among them relating to all of the allegations
contained in the Lawsuit in order to avoid the expense and uncertainty of
further litigation concerning such matters.

         NOW, THEREFORE, for good and valuable consideration, including the
payments, covenants, and agreements contained herein, the sufficiency of which
are hereby acknowledged, the parties hereto agree as follows:

         1. Payment to Plaintiffs by Castle. Castle shall cause Plaintiffs to be
paid the sum of Five Million Seven Hundred and Fifty Thousand Dollars
($5,750,000.00) which payment shall fully satisfy, discharge, and resolve all
disputes and matters arising from, related to, connected with, or which could
have been brought in the Lawsuit. Payment shall be made by wire (to a wire
transfer address to be provided by Plaintiffs) within fifteen (15) days of the
entry of this Agreement and dismissal of the Lawsuit with prejudice.

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         2.A. Indemnification of Defendants by Texaco Inc. Texaco Inc.
("Texaco"), on behalf of Plaintiffs, agrees to defend, hold harmless, and
indemnify Defendants, their current and former affiliates and any of their
respective officers, employees, directors, general and limited partners, and
agents, from and against any and all third party (which shall also include
Pioneer Asphalt Company, Witco Corporation and Chemtura) suits, actions, claims,
losses, liabilities, damages, fines, penalties, costs, expenses, and attorneys'
fees arising out of or related to (1) any of the real or personal property in
Illinois or Indiana that were at any time owned, operated, leased or otherwise
used by Indian Refining Company, Indian Refining I Limited Partnership, or
Indian Refining & Marketing I, Inc.; and (2) any environmental pollution or
releases of petroleum or hazardous substances on, under or from such properties,
or from the business and/or operations of Indian Refining Company, Indian
Refining I Limited Partnership, or Indian Refining & Marketing I, Inc.,
conducted thereon; provided that, with respect to the Lawsuit, each party shall
bear its own litigation costs and attorneys' fees in this case. This agreement
to defend, hold harmless, and indemnify shall include, but shall not be limited
to, claims for environmental response costs, contribution claims, natural
resource damages, or third-party claims for property damages and/or personal
injury, but does not include tax or civil fraud claims.

         2.B. Defendants' Notification of Claims. Defendants shall promptly
notify Texaco of any claim for which indemnification is sought and Texaco's
obligation to indemnify shall be subject to receiving prompt notice of an
indemnity claim except that any alleged delay in notice shall not limit Texaco's
indemnity obligation unless it establishes that it was prejudiced by the delay.

         2.C. Defendants' Duty To Cooperate. Each Defendant shall cooperate with
Texaco in the defense of any claim to which this indemnity applies.

         2.D. Texaco To Control Defense and Settlement. Texaco shall have the
unilateral right to control the defense of any indemnity claim and shall have
the unilateral right to settle any claim to which this indemnity applies.

         2.E. Defendants' Representation. Each Defendant represents that they
know of no environmental, personal injury, property damage or any other lawsuit
for which the Defendants seek indemnity that has been filed against and served
on any of them prior to their execution of this Agreement (except this Lawsuit)
related to any real or personal property in Illinois or Indiana owned, operated
or leased by Indian Refining Company or Indian Refining I Limited Partnership.

                                       2


         3. Mutual Release of Claims By Plaintiffs And Defendants. Plaintiffs
and Defendants agree to release each other, their current and former affiliates
and any of their respective officers, employees, directors, general and limited
partners, and agents, from and against any and all suits, actions, claims,
losses, liabilities, damages, fines, penalties, costs, expenses, and attorneys'
fees arising out of or related to: (1) the Lawsuit; (2) any of the real or
personal property in Illinois or Indiana that were at any time owned, operated,
leased or otherwise used by Indian Refining Company, Indian Refining I Limited
Partnership, or Indian Refining & Marketing I, Inc.; and (3) any environmental
pollution or releases of petroleum or hazardous substances on, under or from
such properties, or from the business and/or operations of Indian Refining
Company, Indian Refining I Limited Partnership, or Indian Refining & Marketing
I, Inc., conducted thereon; provided that, with respect to item (1), each party
shall bear its own litigation costs and attorneys' fees in this case. This
agreement to release shall include, but shall not be limited to, claims for
environmental response costs, contribution claims, natural resource damages, or
third-party claims for property damages and/or personal injury.

         4. Obligations to Survive. The mutual releases expressed herein shall
not include any obligations created hereunder.

         5. Confidentiality. The parties hereto and their respective counsel
shall maintain the confidentiality of the terms of this Agreement until publicly
disclosed by Castle Energy Corporation.

         6. Binding. The terms and provisions of this Agreement will be binding
upon, and inure to the benefit of, all the parties hereto and their respective
representatives, successors, and assigns.

         7. Complete Agreement. The parties hereto stipulate and agree that the
terms and conditions set forth in this Agreement constitute the entire agreement
among the parties, and the parties further agree that this Agreement cannot be
altered in any respect whatsoever absent the written consent of all parties
hereto. Further, the parties stipulate that this Agreement supersedes any
written or oral understanding, promise, or agreement directly or indirectly
related to it, which is not referred to and incorporated herein.

         8. Counterparts. This Agreement may be executed in separate
counterparts, each of which shall be deemed an original, but all of which
together shall constitute but one and the same instrument. This Agreement may
also be executed via facsimile signature(s) which facsimiles shall constitute
the original Agreement.

         9. Consultation with Attorney. All parties acknowledge that they have
consulted with their attorneys concerning the terms of this Agreement, in that
such consultation occurred before the execution of this Agreement. The parties
further agree that this Agreement is the joint work product of all parties
hereto and, in the event of any ambiguity herein, no inference shall be drawn
against a party by reason of document preparation.

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         10. No Admission of Liability. Neither the execution of this Agreement,
nor the compliance with its terms, shall constitute or be construed as an
admission of fault or liability on behalf of any party to this Agreement, which
fault and/or liability is expressly denied.

         11. Severability. If any part of this Agreement is found to be
unenforceable, the remainder of this Agreement shall have full force and effect.

         12. Dismissal With Prejudice. Within five (5) days of the execution by
all parties of this Agreement, Plaintiffs hereby agree to file with the United
States District Court for the Southern District of Illinois their Dismissal With
Prejudice of the Lawsuit as to each of the Defendants herein, each party to bear
its own costs and attorneys' fees, and deliver via U.S. Mail, a file-stamped
copy of the pleading to counsel for Defendants.

         13. No Third Party Rights. This Agreement is not for the benefit of any
third party other than the identified indemnified parties and shall not create
any other third party beneficiary rights.

         14. Notices. Notices under this agreement shall be sent to:

                  Eve Wilkerson-Barron, Sr. Counsel
                  Law Department
                  Environmental Practice Group
                  Chevron U.S.A. Inc.
                  1500 Louisiana, 36th Floor
                  Houston, TX  77002
                  Fax:  832-854-6496



                  William Liedtke, General Counsel       William S. Sudhaus
                  Castle Energy Corp.                    c/o Raymond T. Reott
                  357 South Gulph Road                   Reott Law Offices, LLC
                  Suite 260                              35 East Wacker Drive
                  King of Prussia, PA  19406             Suite 650
                  Fax:  610-992-9922                     Chicago, IL  60611
                                                         Fax:  312-782-4519

         15. Effective Date. This Agreement shall become effective on the date
of execution by all parties.

   THE FOREGOING AGREEMENT HAS BEEN READ AND FULLY UNDERSTOOD BEFORE SIGNING.

         IN WITNESS WHEREOF, the undersigned have set their hand as of the date
and year first written above, having read and fully understanding the above
provisions.


CHEVRON ENVIRONMENTAL                       CHEVRON ENVIRONMENTAL
MANAGEMENT COMPANY                          SERVICES COMPANY


/s/FRANK G. SOLER                           /s/FRANK G. SOLER
- -----------------------------               -----------------------------
Name:    Frank G. Soler                     Name:    Frank G. Soler
- -----------------------------               -----------------------------
Date:    September 19, 2005                 Date:    September 19, 2005
- -----------------------------               -----------------------------
Title:   Assistant Secretary                Title:   Assistant Secretary
- -----------------------------               -----------------------------


TEXACO INC.


/s/FRANK G. SOLER
- -----------------------------
Name:    Frank G. Soler
- -----------------------------
Date:    September 19, 2005
- -----------------------------
Title:   Secretary
- -----------------------------


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INDIAN REFINING I LIMITED            INDIAN REFINING & MARKETING
PARTNERSHIP                          I, INC.


/s/DAVID S. DRAEGER                  /s/DAVID S. DRAEGER
- ----------------------------------   -----------------------------------------
Name:    David S. Draeger            Name:    David S. Draeger
- ----------------------------------   -----------------------------------------
Date:    September 7, 2005           Date:    September 7, 2005
- ----------------------------------   -----------------------------------------
Title:   President                            Title:   President
- ----------------------------------   -----------------------------------------


WILLIAM S. SUDHAUS                   CASTLE ENERGY CORPORATION


/s/WILLIAM S. SUDHAUS                /s/WILLIAM C. LIEDTKE, III
- -----------------------------------  -------------------------------------------
Name:    William S. Sudhaus          Name:    William C. Liedtke, III
- -----------------------------------  -------------------------------------------
Date:    September 14, 2005          Date:    September 7, 2005
- -----------------------------------  -------------------------------------------
Title:                               Title:   Vice President and General Counsel
- -----------------------------------  -------------------------------------------



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