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                                                                  EXHIBIT 10.72



                                February 1, 2000


Mr. Edward de Boer



Dear Edward:

         The purpose of this letter is to state our agreement concerning your
resignation and the termination of your employment with Denali, Incorporated
("Denali"). Our agreement, as stated in this letter, is intended to be legally
binding on and for the benefit of you and Denali (and its affiliates and
representatives). It is also our mutual intent that our agreement, as embodied
in this document, be a final compromise and disposition of any and all claims
or disputes, of any kind, which you have or may have, including those related
to your employment with Denali or the termination of such employment. This
letter agreement may be referred to by name as our "SEVERANCE AGREEMENT AND
RELEASE AND WAIVER OF ALL CLAIMS."

TERMS

         You have offered, and Denali has accepted, your resignation. You will
have no other duties or responsibilities for Denali, effective January 24,
2000. In return for your resignation and your waiver and release of any and all
claims, Denali will pay or provide to you the following severance benefits:

         1. The gross amount, less withholding for taxes, of one hundred and
seventy-three thousand, three hundred and thirty-three and no/100 dollars
($173,333.00), in twelve equal monthly payments, paid on the normal pay date
for Denali, minus required tax withholding. Should you die during this term,
these payments will be made to your wife, but should she also die during this
term, these payments will be made to your surviving children, equally divided
among them.

         2. Payment of an amount equal to the currently active monthly employee
premiums paid by Denali for continuation of your group medical and dental
insurance (the same coverage currently in place) until you become eligible for
health plan coverage in connection with other employment or for twelve months,
whichever occurs first. You will continue to be responsible for payment of the
active employee portion of this coverage.

         3. Acceleration of your vesting in the (1) Incentive Stock Option
Agreement granted on November 20, 1997, to be fully vested with exercise rights
until June 30, 2000; (2) Incentive Stock Option Agreement granted on April 21,
1999, to be 25% vested with exercise rights until June 30, 2000; and (3)
Incentive Stock Option Agreement granted on July 28, 1999, to be 20% vested
with exercise rights until June 30, 2000.

         This agreement does not alter, modify or restrict in any way any
rights you may have under COBRA to obtain continued coverage under Denali's
group health and dental plans.

RELEASE AND WAIVER OF ALL CLAIMS

         1. In consideration of and in return for the severance payments and
benefits stated in this agreement, you hereby agree to release Denali,
Incorporated, including its current and former owners, subsidiaries and
affiliates, directors, officers, employees, agents and successors, and all
benefit plans sponsored by Denali or any of its affiliates ("Denali Parties"),
from liability




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for any and all claims, causes of action, liabilities, damages, and other
remedies, of any kind, whether now known or unknown, including, but not limited
to, any related to your employment by Denali and the termination of your
employment, as well as to any other matter. This release includes, but is not
limited to, claims or causes of action arising under federal and state fair
employment or discrimination laws (including but not limited to any rights or
claims you may have under Title VII of the Civil Rights Act of 1964, as
amended, the Civil Rights Act of 1991, the Age Discrimination in Employment
Act, the Americans With Disabilities Act, the Employee Retirement Income
Security Act, and the Texas Commission on Human Rights Act), laws pertaining to
breach of employment contract, wrongful discharge, common law tort (e.g.,
negligence, infliction of emotional distress, defamation, assault, fraud,
etc.), and/or any other federal, state or local laws relating in any way to
your employment, events occurring during the course of your employment
(including to the date of your acceptance of this agreement), and/or the
termination of your employment with Denali. Our agreement is not intended to
indicate that any such claims exist or that, if they do exist, they are
meritorious. Rather, we are simply agreeing that, IN RETURN FOR DENALI'S
AGREEMENT TO THE SEVERANCE PAYMENTS AND BENEFITS STATED IN THIS LETTER, ANY AND
ALL POTENTIAL CLAIMS THAT YOU MAY HAVE AGAINST THE DENALI PARTIES, REGARDLESS
OF WHETHER THEY ACTUALLY EXIST, ARE EXPRESSLY AND FOREVER SETTLED, COMPROMISED
AND WAIVED. YOU ARE ADVISED TO CONSULT WITH AN ATTORNEY FOR ADVICE PRIOR TO
EXECUTING THIS AGREEMENT.

         You represent to the Denali Parties that you (a) are legally and
mentally competent to make this agreement, (b) that you are the sole owner of
all potential claims that you may have against the Denali Parties and that no
portion of any such claim has been sold or assigned by you to any third party,
and (c) that you possess the exclusive right to receive all of the severance
payments and benefits enumerated in this agreement, (d) that you have been
advised to consult an attorney for advice prior to executing this agreement,
(e) you understand you have at least 21 days from the date this letter was
presented to you to consider whether to execute this agreement, and (f) you
have seven days to revoke this agreement after you execute it.

         You acknowledge that the severance payment and benefits described in
this letter are valuable consideration to which you would not be undisputedly
entitled, but are solely in return for the waiver of rights and claims and your
other agreements as stated in this agreement.


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         2.       You agree, to the extent permitted by law, not to bring or
                  join any lawsuit or file any charge or claim against any of
                  the Denali Parties in any court or before any government
                  agency (except as necessary to protect your rights under this
                  agreement) relating to your employment, events occurring
                  during your employment, the termination of your employment,
                  or any other matter. You further agree that should you assert
                  before any court or government agency that the release and
                  waiver provisions of this agreement are void or unenforceable
                  for any reason, then Denali shall have the right, at its
                  option, to rescind this agreement, in which event you shall
                  be obligated to return to Denali all amounts paid to you as
                  severance benefits under this agreement. You also agree to
                  waive any right to future employment with any of the Denali
                  Parties and agree that you will not seek employment with them
                  in the future.

         You acknowledge that you have already received all other wages or pay
to which you are entitled (including for vacation or other accrued paid leave
time).

COOPERATION

         You agree to cooperate with Denali to the extent reasonably required
in all matters related to the orderly transfer to other Denali representatives
of pending matters on which you were working as of the date of the termination
of your employment. You also agree to act in good faith and to use reasonable
efforts to cooperate with any reasonable request by any representative of
Denali for information or assistance related to matters for which you had
responsibility in your former employment with Denali.

CONFIDENTIALITY

         You agree not to disclose the terms of this Severance Agreement and
Release and Waiver of All Claims to any other person, except that you may
disclose such terms to your attorney, financial advisors and/or tax
accountants, and members of your immediate family. You also agree to refrain
from making public or private statements or comments relating to any of the
Denali Parties which are derogatory or which may tend to injure any such party
or person in its or their business, public or private affairs.

PROPRIETARY AND CONFIDENTIAL INFORMATION

         In accordance with your existing and continuing obligations, you
acknowledge that Denali, Incorporated and its affiliates have developed and own
valuable "Proprietary and Confidential Information" which constitutes valuable
and unique property including, without limitation, concepts, ideas, plans,
strategies, analyses, surveys, and proprietary information related to the past,
present or anticipated business of Denali and its various related entities.
Except as may be required by law, you agree that you will not at any time
disclose to others, permit to be disclosed, use, permit to be used, copy or
permit to be copied, any such Proprietary and Confidential Information (whether
or not developed by you) without the prior written consent of an authorized
representative of Denali. Except as may be required by law, you further agree
to maintain in confidence any Proprietary and Confidential Information of third
parties received or of which you have knowledge as a result of your employment
with Denali. You agree that in the event of any actual or anticipated breach by
you of the provisions of this paragraph, Denali shall be entitled to inform all
potential or new employers of this agreement.

NON-ADMISSION

         You agree that neither the contents of this Severance Agreement and
Release and Waiver of All Claims nor our communications concerning it or
related events constitutes an admission or evidence of wrongdoing of any type
by any of the Denali Parties.



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TAX LIABILITY

         You understand and agree that you will be solely and exclusively
responsible for the entire amount of taxes (except the employer's portion of
Social Security taxes) due on all severance payments and benefits you receive
pursuant to this agreement and that Denali will follow its normal withholding
and reporting practices, as well as fully comply with all legal requirements,
with respect to such payments and benefits.

SEVERABILITY

         In the event that any provision of this agreement is determined in the
future to be invalid, void or unenforceable for any reason, such determination
shall not affect the validity and enforceability of all remaining provisions of
our agreement. The only exception is that a determination that the "Release and
Waiver of All Claims" portion of this agreement is unenforceable shall result
in the entire agreement becoming voidable, at the option of Denali, thereby
requiring the return to Denali of all payments and benefits given in
consideration for those release provisions.

ENTIRE AGREEMENT

         This Severance Agreement and Release and Waiver of All Claims
supersedes, replaces and merges all previous agreements and discussions between
you and Denali relating to the same or similar subject matters and constitutes
the entire agreement between you and Denali with respect to its subject matter.
This Severance Agreement and Release and Waiver of All Claims may not be
changed or terminated orally, and no change, termination or waiver of any of
its provisions shall be binding unless made in writing and signed by all
parties.

REVIEW AND SIGNATURE

         Your signature below will acknowledge that you have carefully read
this Severance Agreement and Release and Waiver of All Claims, that you have
had an adequate opportunity to consider it, and that you fully understand its
final and binding effect; that the only promises made to you to sign this
agreement are those stated in this document; and that you are signing this
document voluntarily and of your own free will, and that you understand and
agree to each of the terms of this Severance Agreement and Release and Waiver
of All Claims.

                                         Sincerely yours,

                                         DENALI, INCORPORATED
                                         By  /s/ RICHARD W. VOLK
                                             -------------------
                                               Richard W. Volk, CEO

         AGREED TO and EXECUTED this 11TH day of February 2000.

                                         /s/ EDWARD DE BOER
                                         -------------------
                                         Edward de Boer