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March 29, 2000



Mr. William Kraemer
MCNIC Pipeline & Processing Company
170 West Jefferson, Suite 1900
Detroit, MI 48226


     RE: OPTION TO REMOVE CROWN ASPHALT CORPORATION AS OPERATOR


Dear Mr. Kraemer:


Pursuant to our recent discussions, both MCNIC Pipeline & Processing Company
("MCNIC") and Crown Asphalt Corporation ("Crown"), in their own capacity and as
all of the members of Crown Asphalt Ridge L.L.C. ("CAR") and in consideration of
additional capital contributions that MCNIC is going to make, have agreed that
MCNIC shall have the right, for a period of time, to remove Crown as Operator
under the Asphalt Ridge Operating and Management Agreement dated as of August 1,
1997 (the "Operating and Management Agreement"). To that end, MCNIC, Crown and
CAR hereby agree that, notwithstanding any provision of the Crown Asphalt Ridge
L.L.C. Operating Agreement, dated as of August 1, 1997 (the "LLC Agreement") or
the Operating and Management Agreement to the contrary, for a period of eighteen
months from the date hereof, at MCNIC's or its successor's or assign's sole
option and upon 30 days prior written notice to Crown and CAR, MCNIC, or its
successor or assign, shall have the right to terminate the Operating and
Management Agreement and remove Crown as Operator under the Operating and
Management Agreement. Such removal shall not relieve CAR of its obligation to
make any and all payments owed to Crown, as Operator under the Operating and
Management Agreement, including any employee payroll, benefits, severance and
other liabilities, which are attributable to the period of time for which Crown
was serving as Operator (the "Outstanding Costs"). Furthermore, prior to the
expiration of the 30 day notice period set forth above, MCNIC agrees that, to
the extent required, it shall have made any and all contributions to CAR
necessary for payment of its proportionate share of any undisputed Outstanding
Costs for which Crown has provided documentation. In the event MCNIC terminates
the Operating and Management Agreement and removes Crown as Operator as provided
above, then MCNIC would be the successor Operator and MCNIC and CAR would
execute a new operating and management agreement substantially in the same form
as the Operating and Management Agreement. It is the intent of the parties that
the termination of the Operating and Management Agreement and removal of Crown
as Operator will not affect Crown's right to serve as Operator for any
Subsequent Plant, Additional Opportunity or AMI Opportunity as described in
Section 15 of the Operating and Management Agreement. The new operating and
management agreement naming MCNIC as successor Operator shall contain provisions
to that effect.


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Mr. William Kraemer
MCNIC Pipeline & Processing Company
March 29, 2000
Page 2


For purposes of this Letter Agreement, terms used but not defined shall have the
meaning assigned to them in the LLC Agreement or the Operating and Management
Agreement as appropriate. Except as specifically provided in this Letter
Agreement, the LLC Agreement and the Operating and Management Agreement will
remain in full force and effect with no changes, amendments or revisions.
Further, by executing this letter, Crown shall not be deemed to be in default in
any way under the LLC Agreement or the Operating and Management Agreement. This
letter shall be binding upon the successors and assigns of MCNIC, Crown and CAR.
If the foregoing accurately reflects our understanding, please execute both
originals in the space provided below. Please return one original to me and
retain the other for your files.


Sincerely,


CROWN ASPHALT CORPORATION


Jay Mealey,
President


Accepted and agreed to
This ____day of January, 2000.

MCNIC PIPELINE & PROCESSING COMPANY



William Kraemer,
Vice President

CROWN ASPHALT RIDGE L.L.C.

By: Crown Asphalt Corporation       By: MCNIC Pipeline & Processing Company
    Its: Member                         Its: Member


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