Exhibit 2

                          AGREEMENT AND PLAN OF MERGER

                                 BY AND BETWEEN

                                 SLH CORPORATION

                                       AND

                             SYNTROLEUM CORPORATION

                           DATED AS OF MARCH 30, 1998







                                TABLE OF CONTENTS

ARTICLE I     THE MERGER................................................. .....1
         1.1    The Merger; Effective Time of the Merger.......................1
         1.2    Closing........................................................1
         1.3    Effects of the Merger..........................................2
                (a)     Surviving Corporation; Charter; Bylaws.................2
                (b)     Directors and Officers.................................2
                (c)     Other..................................................2
ARTICLE II    EFFECT OF THE MERGER ON THE CAPITAL STOCK OF THE
              CONSTITUENT CORPORATIONS; EXCHANGE OF CERTIFICATES...............2
         2.1    Effect of the Merger on Capital Stock..........................2
                (a)     Exchange Ratio for Syntroleum Common Stock.............2
                (b)     Assumption of Syntroleum Stock Options.................3
                (c)     Adjustment of SLH Stock Options........................3
                (d)     Termination of Syntroleum Shareholder Agreements.......4
         2.2    Exchange of Certificates.......................................5
                (a)     Exchange Agent.........................................5
                (b)     Exchange Procedures....................................5
                (c)     Distributions with Respect to Unexchanged Shares.......6
                (d)     No Further Ownership Rights in Syntroleum Common Stock.6
                (e)     No Fractional Shares...................................6
                (f)     Termination of Exchange Fund...........................7
                (g)     No Liability...........................................7
         2.3    Dissenting Shares..............................................7
ARTICLE III   REPRESENTATIONS AND WARRANTIES...................................8
         3.1    Representations and Warranties of Syntroleum...................8
                (a)     Organization, Standing and Power.......................8
                (b)     Capital Structure......................................8
                (c)     Non-Subsidiaries Equity Investment.....................9
                (d)     Authority; No Violations; Consents and Approvals......10
                (e)     Financial Statements..................................11
                (f)     Information Supplied..................................11
                (g)     Absence of Certain Changes or Events..................12
                (h)     No Undisclosed Material Liabilities...................12
                (i)     Material Contracts; No Defaults.......................13
                (j)     Compliance with Applicable Laws.......................14
                (k)     Litigation............................................15
                (l)     Taxes.................................................15
                (m)     Pension and Benefit Plans; ERISA......................17
                (n)     Labor Matters.........................................19
                (o)     Intangible Property...................................19
                (p)     Environmental Matters.................................20

                                        i


                (q)     Opinion of Financial Advisor..........................22
                (r)     Vote Required.........................................22
                (s)     Insurance.............................................23
                (t)     Brokers...............................................23
                (u)     Tax Matters...........................................23
                (v)     Title.................................................23
                (w)     Books and Records.....................................23
                (x)     Certain Payments......................................24
                (y)     Transactions with Related Parties.....................24
                (z)     State Takeover Laws...................................24
                (aa)    Year 2000.............................................24
         3.2    Representations and Warranties of SLH.........................24
                (a)     Organization, Standing and Power......................24
                (b)     Capital Structure.....................................25
                (c)     Non-Subsidiaries Equity Investment....................26
                (d)     Authority; No Violations; Consents and Approvals......26
                (e)     SEC Documents.........................................28
                (f)     Information Supplied..................................28
                (g)     Absence of Certain Changes or Events..................29
                (h)     No Undisclosed Material Liabilities...................29
                (i)     Material Contracts; No Defaults.......................29
                (j)     Compliance with Applicable Laws.......................30
                (k)     Litigation............................................30
                (l)     Taxes.................................................31
                (m)     Pension and Benefit Plans; ERISA......................32
                (n)     Labor Matters.........................................34
                (o)     Intangible Property...................................35
                (p)     Environmental Matters.................................35
                (q)     Opinion of Financial Advisor..........................36
                (r)     Vote Required.........................................37
                (s)     Insurance.............................................37
                (t)     Brokers...............................................37
                (u)     Tax Matters...........................................37
                (v)     Title.................................................37
                (w)     Books and Records.....................................37
                (x)     Certain Payments......................................38
                (y)     Transactions with Related Parties.....................38
                (z)     State Takeover Laws and SLH Rights Plan...............38
                (aa)    Year 2000.............................................38
ARTICLE IV    COVENANTS RELATING TO CONDUCT OF BUSINESS.......................38
         4.1    Conduct of Business by Syntroleum Pending the Merger..........38
                (a)     Ordinary Course.......................................39
                (b)     Dividends; Changes in Stock...........................39

                                       ii


                (c)     Issuance of Securities................................39
                (d)     Governing Documents...................................39
                (e)     No Acquisitions.......................................39
                (f)     No Dispositions.......................................39
                (g)     No Dissolution, Etc...................................40
                (h)     Certain Employee Matters..............................40
                (i)     Indebtedness; Leases; Capital Expenditures............40
                (j)     No Solicitation.......................................40
         4.2    Conduct of Business by SLH Pending the Merger.................41
                (a)     Ordinary Course.......................................41
                (b)     Dividends; Changes in Stock...........................42
                (c)     Issuance of Securities................................42
                (d)     Governing Documents...................................42
                (e)     No Acquisitions.......................................42
                (f)     No Dispositions.......................................42
                (g)     No Dissolution, Etc...................................43
                (h)     Certain Employee Matters..............................43
                (i)     Indebtedness; Leases; Capital Expenditures............43
                (j)     No Solicitation.......................................43
ARTICLE V     ADDITIONAL AGREEMENTS...........................................44
         5.1    Preparation of S-4 and the Proxy Statement....................44
         5.2    Letter of Syntroleum's Accountants............................45
         5.3    Letter of SLH's Accountants...................................45
         5.4    Access to Information.........................................45
         5.5    Stockholders Meetings.........................................45
         5.6    Legal Conditions to Merger....................................46
         5.7    Agreements of Others..........................................46
         5.8    Listing.......................................................46
         5.9    Board of Directors and Officers.  ............................46
         5.10   Stock Options; Reservation and Registration of Shares.........47
         5.11   Indemnification; Directors' and Officers' Insurance...........47
         5.12   Public Announcements..........................................48
         5.13   Other Actions.................................................49
         5.14   Advice of Changes; SEC Filings................................49
         5.15   Reorganization................................................49
         5.16   Termination of Certain SLH Employees..........................49
ARTICLE VI    CONDITIONS PRECEDENT............................................49
         6.1    Conditions to Each Party's Obligation to Effect the Merger....49
                (a)     Stockholder Approval..................................49
                (b)     Listing...............................................50
                (c)     Other Approvals.......................................50
                (d)     S-4...................................................50
                (e)     No Injunctions or Restraints..........................50
                                       iii


                (f)     Dissenters............................................50
                (g)     Accounting Treatment..................................50
                (h)     Tax Opinion...........................................50
         6.2    Conditions of Obligations of SLH..............................51
                (a)     Representations and Warranties........................51
                (b)     Performance of Obligations of Syntroleum..............51
                (c)     No Vesting of Syntroleum Stock Options................51
                (d)     Fairness Opinion......................................51
                (e)     Officers' Certificate.................................51
                (f)     Letters from Affiliates...............................51
                (g)     Opinion of Counsel to Syntroleum......................52
         6.3    Conditions of Obligations of Syntroleum.......................52
                (a)     Representations and Warranties........................52
                (b)     Performance of Obligations of SLH.....................52
                (c)     Fairness Opinion......................................52
                (d)     Officers' Certificate.................................52
                (e)     Board of Directors and Officers at the Effective Time.52
                (f)     Opinion of Counsel to SLH.............................52
                (g)     Consents of Optionees.................................53
ARTICLE VII   TERMINATION AND AMENDMENT.......................................53
         7.1    Termination...................................................53
         7.2    Effect of Termination.........................................54
         7.3    Amendment.....................................................55
         7.4    Extension; Waiver.............................................55
ARTICLE VIII  GENERAL PROVISIONS..............................................55
         8.1    Payment of Expenses...........................................55
         8.2    Nonsurvival of Representations, Warranties and Agreements.....55
         8.3    Notices.......................................................56
         8.4    Interpretation................................................57
         8.5    Counterparts..................................................57
         8.6    Entire Agreement; No Third Party Beneficiaries................57
         8.7    Governing Law.................................................58
         8.8    Severability..................................................58
         8.9    Assignment....................................................58

                                       iv



                  EXHIBITS TO THE AGREEMENT AND PLAN OF MERGER


Exhibit                    Description

Exhibit A         --Form of Certificate of Merger
Exhibit B         --List of Directors and Officers of Surviving Corporation
Exhibit C         --Tax Certificate
Exhibit D         --Opinion of Counsel to Syntroleum
Exhibit E         --Opinion of Counsel to SLH



                                        v



                            GLOSSARY OF DEFINED TERMS

                                                                  Defined
Defined Term                                                     in Section
- ------------                                                   -------------- 

Affiliates.....................................................    5.7
Agreement......................................................    Preamble
CERCLA.........................................................    3.1(p)(A)
Certificate of Merger..........................................    1.1
Certificates...................................................    2.2(b)
Closing........................................................    1.1
Closing Date...................................................    1.2
Code...........................................................    Recitals
Confidentiality Agreements.....................................    5.4
Consultant Option..............................................    3.1(b)
Constituent Corporations.......................................    1.3(a)
Contracts......................................................    3.1(i)(ii)
Dissenting Shares..............................................    2.3
Effective Time.................................................    1.1
Environmental Law..............................................    3.1(p)(A)
ERISA..........................................................    3.1(m)(i)(1)
Exchange Act...................................................    3.1(b)
Exchange Agent.................................................    2.2(a)
Exchange Fund..................................................    2.2(a)
Exchange Ratio.................................................    2.1(a)
GAAP...........................................................    3.1(e)
Governmental Entity............................................    3.1(d)(iii)
Hazardous Material.............................................    3.1(p)(B)
Indemnified Liabilities........................................    5.11
Indemnified Parties............................................    5.11
Injunction.....................................................    6.1(e)
IRS............................................................    3.1(l)(ii)
Kansas Code....................................................    1.1
Merger.........................................................    Recitals
OSHA...........................................................    3.1(p)(A)
Oklahoma Act...................................................    1.1
Optionee.......................................................    2.1(c)
PBGC...........................................................    3.1(m)(ii)(5)
Proxy Statement................................................    3.1(f)
Release........................................................    3.1(p)(C)
Remedial Action................................................    3.1(p)(D)
Returns........................................................    3.1(l)(i)
S-4............................................................    3.1(f)

                                       vi


SEC............................................................    3.1(f)
Securities Act.................................................    3.1(f)
Shares.........................................................    2.1(a)
SLH............................................................    Preamble
SLH Acquisition Proposal.......................................    4.2(j)
SLH Benefit Programs...........................................    3.2(m)(i)(2)
SLH Common Stock...............................................    2.1(a)
SLH Common Stock Market Value..................................    2.1(a)
SLH Intangible Property........................................    3.2(o)
SLH Junior Preferred Stock.....................................    2.1(a)
SLH Letter.....................................................    3.2(a)
SLH Litigation.................................................    3.2(k)
SLH Material Adverse Change....................................    3.2(a)
SLH Material Adverse Effect....................................    3.2(a)
SLH Order......................................................    3.2(k)
SLH Permits....................................................    3.2(j)
SLH Plans......................................................    3.2(m)(i)(1)
SLH Preferred Stock............................................    3.2(b)
SLH Representatives............................................    4.2(j)
SLH Rights Agreement...........................................    2.1(a)
SLH SEC Documents..............................................    3.2(e)
SLH Stock Option...............................................    2.1(c)
SLH Stock Option Plan..........................................    2.1(c)
SLH Stock Purchase Rights......................................    2.1(a)
SLH Stockholder Meeting........................................    5.5
SLH Voting Debt................................................    3.2(b)
Stockholder Meetings...........................................    5.5
Subsidiary.....................................................    3.1(a)
Surviving Corporation..........................................    1.3(a)
Syntroleum.....................................................    Preamble
Syntroleum Acquisition Proposal................................    4.1(j)
Syntroleum Benefit Programs....................................    3.1(m)(i)(2)
Syntroleum Common Stock........................................    2.1(a)
Syntroleum Common Stock Market Value...........................    2.1(a)
Syntroleum Commonly Controlled Entity..........................    3.1(m)(ii)(8)
Syntroleum Financial Statements................................    3.1(e)
Syntroleum Intangible Property.................................    3.1(o)
Syntroleum Letter..............................................    3.1(a)
Syntroleum Litigation..........................................    3.1(k)
Syntroleum Material Adverse Change.............................    3.1(a)
Syntroleum Material Adverse Effect.............................    3.1(a)
Syntroleum Order...............................................    3.1(k)
Syntroleum Permits.............................................    3.1(j)

                                       vii


Syntroleum Plans...............................................    3.1(m)(i)(1)
Syntroleum Preferred Stock.....................................    3.1(b)
Syntroleum Representatives.....................................    4.1(j)
Syntroleum Stock Option........................................    5.10
Syntroleum Stock Option Plans..................................    3.1(b)
Syntroleum Stockholder Meeting.................................    5.5
Syntroleum Voting Debt.........................................    3.1(b)
Taxes..........................................................    3.1(l)
Trading Day....................................................    2.1(a)


                                      viii

                          AGREEMENT AND PLAN OF MERGER

         AGREEMENT  AND  PLAN OF  MERGER,  dated  as of  March  30,  1998  (this
"Agreement"),  by and between SLH Corporation, a Kansas corporation ("SLH"), and
Syntroleum Corporation, an Oklahoma corporation ("Syntroleum").

         WHEREAS,  the  Boards  of  Directors  of SLH and  Syntroleum  each have
determined  that it is in furtherance of and  consistent  with their  respective
long-term business  strategies and is fair to and in the best interests of their
respective stockholders for Syntroleum to merge with and into SLH (the "Merger")
upon the terms and subject to the conditions of this Agreement;

         WHEREAS,  for federal  income tax  purposes,  it is  intended  that the
Merger shall qualify as a reorganization within the meaning of Section 368(a) of
the United States Internal Revenue Code of 1986, as amended (the "Code"); and

         WHEREAS,  SLH and  Syntroleum  desire to make certain  representations,
warranties,  covenants and agreements in connection  with the Merger and also to
prescribe various conditions to the Merger;

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


                                    ARTICLE I

                                   THE MERGER

         1.1 The  Merger;  Effective  Time of the  Merger.  Upon the  terms  and
conditions  of this  Agreement  and in  accordance  with  the  Oklahoma  General
Corporation  Act (the "Oklahoma  Act") and the Kansas General  Corporation  Code
(the  "Kansas  Code"),  Syntroleum  shall  be  merged  with  and into SLH at the
Effective Time (as hereinafter defined). The Merger shall become effective as of
the date  indicated in a certificate  of merger (the  "Certificate  of Merger"),
prepared and executed in accordance with the relevant provisions of the Oklahoma
Act and the Kansas Code, that is filed with the Secretary of State of the States
of Oklahoma  and Kansas  pursuant to the  Oklahoma  Act and the Kansas Code (the
"Effective  Time").  The filing of the Certificate of Merger shall be made upon,
or as soon as practicable after, the closing of the Merger (the "Closing").  The
Certificate  of Merger shall be in  substantially  the form  attached  hereto as
Exhibit A.

         1.2  Closing.  The Closing  shall take place at 10:00 a.m. on the first
business day after satisfaction (or waiver in accordance with this Agreement) of
the latest to occur of the conditions  (other than  deliveries of instruments to
be made at Closing) set forth in Article VI (the "Closing Date"), at the offices
of Baker & Botts,  L.L.P.,  910 Louisiana,  Houston,  Texas 77002 unless another
date or place is agreed to in writing by the parties.

                                        1

         1.3      Effects of the Merger.

         (a) Surviving Corporation;  Charter; Bylaws. At the Effective Time: (i)
Syntroleum  shall be  merged  with and  into  SLH,  the  separate  existence  of
Syntroleum shall cease and SLH shall continue as the surviving  corporation (SLH
and   Syntroleum   are  sometimes   referred  to  herein  as  the   "Constituent
Corporations"  and the SLH is  sometimes  referred  to herein as the  "Surviving
Corporation");   (ii)  the  Articles  of  Incorporation  of  SLH  as  in  effect
immediately  prior to the Effective Time shall be the Articles of  Incorporation
of the Surviving  Corporation;  provided that, the Articles of  Incorporation of
SLH shall be amended by the  Certificate of Merger to (a) change the name of the
Surviving Corporation to "Syntroleum Corporation" and (b) increase the number of
authorized  shares of SLH Common Stock (as defined below) to 150,000,000  and to
increase  the number of  authorized  shares of SLH  Preferred  Stock (as defined
below) to 5,000,000 and (iii) the Bylaws of SLH as in effect  immediately  prior
to the Effective Time shall be the Bylaws of the Surviving Corporation.

         (b) Directors and Officers.  The individuals listed on Exhibit B hereto
shall,  from and after the Effective  Time, be the directors and officers of the
Surviving  Corporation  and shall serve until  their  successors  have been duly
elected or appointed and qualified or until their earlier death,  resignation or
removal in accordance with the Surviving Corporation's Articles of Incorporation
and Bylaws.

         (c)      Other.  The Merger shall have such other effects as  specified
in the Oklahoma Act and the Kansas Code.


                                   ARTICLE II

                EFFECT OF THE MERGER ON THE CAPITAL STOCK OF THE
               CONSTITUENT CORPORATIONS; EXCHANGE OF CERTIFICATES

         2.1 Effect of the Merger on Capital  Stock.  At the Effective  Time, by
virtue of the  Merger  and  without  any  action on the part of the  Constituent
Corporations or their respective stockholders:

         (a)  Exchange  Ratio  for  Syntroleum  Common  Stock.  Subject  to  the
provisions  of Section  2.2(e)  hereof,  each share of common  stock,  par value
$0.001  per  share,  of  Syntroleum   ("Syntroleum  Common  Stock")  issued  and
outstanding  immediately  prior to the  Effective  Time (other  than  Dissenting
Shares (as  hereinafter  defined)) shall be converted into a number of shares of
common stock,  par value $0.01 per share,  of SLH ("SLH Common  Stock") equal to
the Exchange  Ratio (as  hereinafter  defined)  (such shares  issuable upon such
conversion  are  referred  to  herein  as  the  "Shares"),   together  with  the
corresponding  number of associated  rights (the "SLH Stock Purchase Rights") to
purchase  one-sixth  of one  one-hundredth  of a share of  junior  participating
preferred stock, par value $0.01 per share ("SLH Junior  Preferred  Stock"),  of
SLH pursuant to the Rights Agreement (the "SLH Rights  Agreement") dated January
31, 1997 between SLH and American

                                        2


Stock Transfer & Trust Company. All such shares of Syntroleum Common Stock, when
so converted, shall no longer be outstanding and shall automatically be canceled
and  retired  and  shall  cease to  exist,  and  each  holder  of a  certificate
representing  any  such  shares  shall  cease to have any  rights  with  respect
thereto,  except  the  right to  receive  the  shares  of SLH  Common  Stock and
associated  SLH Stock Purchase  Rights and cash in lieu of fractional  shares of
SLH Common  Stock as  contemplated  by Section  2.2(e),  to be issued or paid in
consideration therefor upon the surrender of such certificate in accordance with
Section  2.2,  without  interest.  "Exchange  Ratio"  shall  mean  the  quotient
(calculated to the nearest five decimal places) obtained by dividing  Syntroleum
Common  Stock  Market  Value (as  hereinafter  defined) by the SLH Common  Stock
Market Value (as hereinafter  defined).  "Syntroleum  Common Stock Market Value"
shall mean the  quotient  obtained by dividing (i) the excess of (A) the product
of (1) the SLH Common Stock Market Value  multiplied  by (2)  10,519,121  (which
number  reflects  the sum of the number of shares of SLH Common Stock issued and
outstanding  as of March 12, 1998 plus the number of shares of SLH Common  Stock
issuable  pursuant to SLH Stock  Options  (as  hereinafter  defined)  which were
vested as of March 12,  1998 plus  250,000  shares of SLH  Common  Stock  (which
reflects a portion of the number of shares of SLH Common Stock issuable pursuant
to SLH Stock  Options  which are not vested as of March 12,  1998)) over (B) the
total  stockholders'   equity  of  SLH  reflected  in  the  unaudited  financial
statements of SLH as of March 31, 1998,  minus the book value reflected  therein
of the shares of Syntroleum  Common Stock held by SLH by (ii)  5,950,000  (which
number  reflects the number of shares of Syntroleum  Common Stock held by SLH as
of the date  hereof).  "SLH Common  Stock  Market  Value" shall mean the average
closing  price of a share of SLH Common  Stock  during the five Trading Days (as
hereinafter  defined) ending on the business day immediately  preceding the date
of the SLH  Stockholder  Meeting  (as  hereinafter  defined)  or in case no such
reported  sale takes  place on such  Trading  Day the  average  of the  reported
closing bid and asked prices of a share of SLH Common Stock on such Trading Day,
in either  case on the Nasdaq  National  Market,  or if the shares of SLH Common
Stock are not quoted on such Nasdaq  National  Market on such  Trading  Day, the
average of the  closing bid and asked  prices of a share of SLH Common  Stock in
the  over-the-counter  market on such  Trading Day as  furnished by any New York
Stock Exchange member firm mutually  selected by SLH and Syntroleum,  or if such
closing bid and asked  prices are not made  available by any such New York Stock
Exchange  member firm on such  Trading  Day,  the market value of a share of SLH
Common Stock as mutually  determined by SLH and Syntroleum.  "Trading Day" shall
mean each weekday  other than any day on which SLH Common Stock is not traded on
the Nasdaq National Market System or in the over-the-counter market.

         (b)      Assumption of  Syntroleum  Stock  Options.   Each  outstanding
Syntroleum Stock Option (as defined in Section 5.10) shall be assumed by SLH  as
provided in Section 5.10.  No Syntroleum Stock Options shall vest as a result of
the Merger.

         (c)  Adjustment of SLH Stock  Options.  Each  outstanding  option ("SLH
Stock Option") to purchase shares of SLH Common Stock under the SLH's 1997 Stock
Incentive  Plan (the "SLH Stock Option Plan") shall be adjusted at the Effective
Time in the  following  manner if such  adjustment is consented to in writing by
the holder of the SLH Stock Option and the written consent

                                        3

is  delivered  to SLH prior to the  Effective  Time  (with  any such  consenting
optionee hereinafter referred to in this Section 2.1(b) as an "Optionee"):

                  (i) such SLH Stock  Options  shall not vest as a result of the
         Merger, and the Merger shall not be deemed to involve any of the events
         described in Section 9 of the SLH Stock Option Plan (so that the Merger
         shall not trigger the immediate vesting of otherwise unvested SLH Stock
         Options  outstanding  at the Effective Time as provided in such Section
         9); and

                  (ii) the exercise  provisions of all SLH Stock Options held by
         an Optionee at the Effective Time shall be adjusted as follows:

                           (A) with  respect to an Optionee who is a director of
                  SLH as of the date hereof and does not  continue as a director
                  of SLH  following  the  Effective  Time and with respect to an
                  Optionee who is an employee  (and not a director) of SLH as of
                  the date  hereof and does not  continue  as an employee of SLH
                  following  the  Effective  Time,  (1) if he dies  prior to the
                  fifth  anniversary of the Effective  Time,  then the SLH Stock
                  Option may be  exercised to the extent  otherwise  exercisable
                  within  one year  following  the date of death;  and (2) if he
                  does not die prior to the fifth  anniversary  of the Effective
                  Time,  then the SLH Stock  Option may be exercised at any time
                  prior to the fifth  anniversary  of the Effective Time but may
                  not be exercised after the fifth  anniversary of the Effective
                  Time; and

                           (B) with  respect to an Optionee who is a director of
                  SLH as of the date hereof and  continues  as a director of SLH
                  following  the  Effective  Time,  (1) if he dies  prior to the
                  fifth  anniversary  of the Effective  Time or prior to 90 days
                  after he ceases to be a director of Syntroleum, whichever last
                  occurs,  then the SLH Stock  Option  may be  exercised  to the
                  extent  otherwise  exercisable  within one year  following the
                  date of  death;  and (2) if he does not die prior to the fifth
                  anniversary of the Effective  Time,  then the SLH Stock Option
                  may be exercised to the extent  otherwise  exercisable  at any
                  time  prior to the later of (a) the fifth  anniversary  of the
                  Effective  Time or (b) 90 days following the date the Optionee
                  ceases to be a director of SLH; provided, that in no event may
                  the SLH Stock Option be exercised after March 3, 2007.

                  (iii) The  foregoing  shall be deemed to adjust and  otherwise
         supersede any conflicting  provisions contained in the SLH Stock Option
         Plan or the option agreements covering the SLH Stock Options, including
         the provisions of Section 3 of each such option agreements.

         (d)      Termination  of   Syntroleum   Shareholder  Agreements.   Upon
consummation  of  the  Merger  (which  will  constitute  a  public  offering  of
Syntroleum Common Stock as contemplated by

                                        4

Syntroleum  shareholder  agreements),  Syntroleum  shareholder  agreements shall
terminate and be of no further force or effect.

         2.2      Exchange of Certificates.

         (a) Exchange  Agent.  As of the Effective  Time, SLH shall deposit with
American  Stock  Transfer & Trust  Company  or such other bank or trust  company
designated  by SLH  and  reasonably  acceptable  to  Syntroleum  (the  "Exchange
Agent"),  for the benefit of the holders of shares of  Syntroleum  Common Stock,
for exchange in  accordance  with this Article II,  through the Exchange  Agent,
cash or SLH Common  Stock (to be sold and  converted  into cash by the  Exchange
Agent) in an amount sufficient to satisfy the obligations of SLH with respect to
payments  for   fractional   shares   pursuant  to  Section  2.2(e)  hereof  and
certificates  representing the Shares (such cash and shares of SLH Common Stock,
together  with any  dividends  or  distributions  with  respect  thereto,  being
hereinafter  referred to as the  "Exchange  Fund").  The  Exchange  Agent shall,
pursuant to irrevocable  instructions,  deliver the cash and Shares contemplated
to be issued  pursuant to Sections 2.1 and 2.2(e) out of the Exchange  Fund. The
Exchange Fund shall not be used for any other purpose.

         (b) Exchange  Procedures.  As soon as reasonably  practicable after the
Effective  Time,  the  Exchange  Agent  shall mail to each holder of record of a
certificate or  certificates  which,  immediately  prior to the Effective  Time,
represented  outstanding shares of Syntroleum Common Stock (the "Certificates"),
which holder's  shares of Syntroleum  Common Stock were converted into the right
to receive  shares of SLH Common Stock  pursuant to Section 2.1: (i) a letter of
transmittal  (which shall  specify that  delivery  shall be effected and risk of
loss and  title  to the  Certificates  shall  pass  only  upon  delivery  of the
Certificates  to the  Exchange  Agent,  and  shall be in such form and have such
other  provisions  as SLH and  Syntroleum  may  reasonably  specify);  and  (ii)
instructions  for use in effecting the surrender of the Certificates in exchange
for certificates  representing  shares of SLH Common Stock.  Upon surrender of a
Certificate  for  cancellation  to the Exchange  Agent or to such other agent or
agents as may be appointed  by SLH,  together  with such letter of  transmittal,
duly executed, and any other required documents,  the holder of such Certificate
shall be entitled to receive in exchange therefor certificates representing that
number of whole  Shares  which such holder has the right to receive  pursuant to
the  provisions  of this  Article  II and cash in lieu of  fractional  Shares as
contemplated  by Section  2.2(e),  and the  Certificates  so  surrendered  shall
forthwith  be canceled.  In the event of a transfer of  ownership of  Syntroleum
Common  Stock  which  is  not  registered  in  the  share  transfer  records  of
Syntroleum,  certificates  representing the appropriate  number of shares of SLH
Common Stock may be issued to a transferee if the Certificates representing such
Syntroleum  Common Stock are presented to the Exchange Agent  accompanied by all
documents required to evidence and effect such transfer and by evidence that any
applicable   stock  transfer  taxes  have  been  paid.   Until   surrendered  as
contemplated  by this Section 2.2,  each  Certificate  (other than  Certificates
representing  Dissenting Shares) shall be deemed at any time after the Effective
Time to represent only the right to receive upon such surrender the certificates
representing  shares  of SLH  Common  Stock  and cash in lieu of any  fractional
shares of SLH Common  Stock as  contemplated  by this  Section 2.2. The Exchange
Agent shall not be entitled to vote or  exercise  any rights of  ownership  with
respect to the SLH Common Stock held by it from time

                                        5

to time hereunder,  except that it shall receive and hold all dividends or other
distributions  paid or  distributed  with  respect  thereto  for the  account of
persons entitled thereto.

         (c) Distributions  with Respect to Unexchanged  Shares. No dividends or
other  distributions with respect to SLH Common Stock declared or made before or
after the Effective  Time with a record date after the  Effective  Time shall be
paid to the holder of any unsurrendered Certificate with respect to the right to
receive  shares of SLH Common Stock  represented  thereby and no cash payment in
lieu of fractional  shares shall be paid to any such holder  pursuant to Section
2.2(e) until the holder of such  Certificate  shall surrender such  Certificate.
Subject  to the  effect of  applicable  laws,  following  surrender  of any such
Certificate  (other than Certificates  representing  Dissenting  Shares),  there
shall  be  paid  to  the  holder  thereof,  without  interest  (in  addition  to
certificates  representing that number of whole Shares which such holder has the
right to receive pursuant to the provisions of this Article II): (i) at the time
of such  surrender,  the amount of any cash  payable  in lieu of any  fractional
share of SLH Common  Stock to which such holder is entitled  pursuant to Section
2.2(e) and the amount of  dividends  or other  distributions  with a record date
after the Effective Time  theretofore  paid with respect to such whole shares of
SLH  Common  Stock;  and (ii) at the  appropriate  payment  date,  the amount of
dividends or other distributions with a record date after the Effective Time but
prior to surrender  and a payment  date  subsequent  to  surrender  payable with
respect to such whole shares of SLH Common Stock.

         (d) No Further  Ownership Rights in Syntroleum Common Stock. All shares
of SLH  Common  Stock  issued  upon the  surrender  for  exchange  of  shares of
Syntroleum  Common Stock in accordance with the terms hereof (including any cash
paid  pursuant to Section  2.2(c) or 2.2(e)) shall be deemed to have been issued
in full  satisfaction  of all rights  pertaining  to such  shares of  Syntroleum
Common Stock, subject, however, to the Surviving Corporation's obligation to pay
any  dividends or make any other  distributions  with a record date prior to the
Effective  Time that may have been declared or made by Syntroleum on such shares
of  Syntroleum  Common Stock in accordance  with the terms of this  Agreement or
prior to the date hereof and which  remain  unpaid at the  Effective  Time,  and
after the Effective Time there shall be no further  registration of transfers on
the  share  transfer  books  of  the  Surviving  Corporation  of the  shares  of
Syntroleum Common Stock that were outstanding immediately prior to the Effective
Time. If, after the Effective Time,  Certificates are presented to the Surviving
Corporation for any reason,  they shall be canceled and exchanged as provided in
this Article II.

         (e)  No  Fractional  Shares.  No  certificates  or  scrip  representing
fractional  shares of SLH Common  Stock shall be issued upon the  surrender  for
exchange of Certificates pursuant to this Article II, and, except as provided in
this Section 2.2(e), no dividend or other distribution,  stock split or interest
shall relate to any such  fractional  security,  and such  fractional  interests
shall not  entitle  the owner  thereof  to vote or to any  rights of a  security
holder of SLH. In lieu of any fractional share of SLH Common Stock,  each holder
of shares of Syntroleum Common Stock who would otherwise have been entitled to a
fraction  of a share of SLH Common  Stock upon  surrender  of  Certificates  for
exchange  pursuant  to this  Article II will be paid an amount in cash  (without
interest)  equal to the value of such fraction of a share based upon the closing
price of SLH Common Stock on the Nasdaq

                                        6

Stock Market on the date on which the Effective  Time shall occur (or if the SLH
Common Stock shall not trade on the Nasdaq Stock Market on such date,  the first
day of that SLH Common Stock shall trade on the Nasdaq Stock Market thereafter).
All  shares  of  Syntroleum  Common  Stock  held by a  record  holder  shall  be
aggregated for purposes of computing the number of shares of SLH Common Stock to
be issued pursuant to this Section 2.2(e).

         (f)  Termination of Exchange Fund. Any portion of the Exchange Fund and
any cash in lieu of fractional  shares of SLH Common Stock made available to the
Exchange  Agent  that  remain   undistributed  to  the  former  stockholders  of
Syntroleum  on or after the  one-hundred  eightieth  day following the Effective
Time shall be delivered to SLH, upon demand,  and any stockholders of Syntroleum
who have not  theretofore  complied with this Article II shall  thereafter  look
only to SLH for payment of their claim for SLH Common Stock, any cash in lieu of
fractional  shares of SLH Common Stock and any dividends or  distributions  with
respect to SLH Common Stock.

         (g) No  Liability.  Neither SLH nor  Syntroleum  shall be liable to any
holder of shares of Syntroleum Common Stock or SLH Common Stock, as the case may
be, for such shares (or dividends or distributions with respect thereto) or cash
in lieu of fractional  shares of SLH Common Stock delivered to a public official
pursuant to any  applicable  abandoned  property,  escheat or similar  law.  Any
amounts remaining unclaimed by holders of any such shares on the day immediately
preceding  the day on which such amounts  would  otherwise  escheat to or become
property of any governmental entity shall, to the extent permitted by applicable
law,  become the property of SLH free and clear of any claims or interest of any
such holders or their successors, assigns or personal representatives previously
entitled thereto.

         2.3 Dissenting  Shares.  Notwithstanding  anything in this Agreement to
the contrary,  shares of Syntroleum Common Stock that are issued and outstanding
immediately  prior to the Effective Time and which are held by stockholders  who
have properly exercised appraisal rights with respect thereto under the Oklahoma
Act (the "Dissenting Shares") shall not be converted into or represent the right
to receive  shares of SLH Common  Stock as provided in Section  2.1(a),  but the
holders of  Dissenting  Shares  shall be entitled to receive such payment of the
appraised  value of such shares held by them from the Surviving  Corporation  as
shall be determined pursuant to the Oklahoma Act; provided, however, that if any
such holder shall have failed to perfect or shall  withdraw or lose the right to
appraisal and payment  under the Oklahoma  Act, each such holder's  shares shall
thereupon  be deemed to have been  converted as of the  Effective  Time into the
right to receive shares of SLH Common Stock,  without any interest  thereon,  as
provided in Section 2.1(a), and upon surrender in the manner provided in Section
2.2 of the Certificate(s)  representing such shares, such shares shall no longer
be Dissenting Shares.

                                        7


                                   ARTICLE III

                         REPRESENTATIONS AND WARRANTIES

         3.1      Representations  and  Warranties  of  Syntroleum.   Syntroleum
represents and warrants to SLH as follows:

         (a)  Organization,  Standing  and  Power.  Each of  Syntroleum  and its
Subsidiaries  (as  defined  below)  is a  corporation,  partnership  or  limited
liability  company duly organized,  validly  existing and in good standing under
the laws of the  jurisdiction  of its  incorporation  or  organization,  has all
requisite  power and authority to own,  lease and operate its  properties and to
carry on its business as now being conducted,  and is duly qualified and in good
standing  to do  business  in each  jurisdiction  in which  the  business  it is
conducting, or the operation, ownership or leasing of its properties, makes such
qualification  necessary,  other than in such jurisdictions where the failure to
qualify would not have a Syntroleum  Material Adverse Effect (as defined below).
Syntroleum  has  heretofore  delivered to SLH complete and correct copies of its
Certificate of Incorporation and Bylaws and the organizational documents of each
of  its  Subsidiaries.   All  Subsidiaries  of  Syntroleum,  the  percentage  of
Syntroleum's  ownership  of  such  Subsidiaries,  the  identity  and  percentage
ownership of all other persons with equity  interests in such  Subsidiaries  and
their  respective  jurisdictions of incorporation or organization are identified
on Schedule  3.1(a) of the letter dated and  delivered to SLH on the date hereof
(the  "Syntroleum  Letter"),  which relates to this  Agreement and is designated
therein as being  Syntroleum  Letter.  As used in this Agreement,  a "Syntroleum
Material Adverse Effect" or "Syntroleum  Material Adverse Change" shall mean any
effect or change that is,  individually or in the aggregate,  materially adverse
to the  business,  operations,  assets,  condition  (financial  or otherwise) or
results of operation of Syntroleum and its Subsidiaries  taken as a whole except
for  general  economic  changes and changes  that may affect the  industries  of
Syntroleum  or any of its  Subsidiaries  generally.  As used in this  Agreement,
"Subsidiary" or "Subsidiaries" means, with respect to any party, any corporation
or other  organization,  whether  incorporated or unincorporated,  of which: (i)
such party or any other Subsidiary of such party is a general partner (excluding
partnerships,  the general partner  interests of which are held by such party or
any Subsidiary of such party that do not have a majority of the voting  interest
in such  partnership);  or (ii) at least a majority of the  securities  or other
interests having by their terms ordinary voting power to elect a majority of the
Board of Directors or others  performing  similar functions with respect to such
corporation  or  other  organization  is,  directly  or  indirectly,   owned  or
controlled by such party or by any one or more of its  Subsidiaries,  or by such
party and any one or more of its Subsidiaries.

         (b) Capital  Structure.  As of the date hereof,  the authorized capital
stock of Syntroleum consists of 50,000,000 shares of Syntroleum Common Stock and
1,000,000  shares of  preferred  stock,  par value $0.01 per share  ("Syntroleum
Preferred  Stock").  At the close of business on the date hereof, (i) 18,993,950
shares of Syntroleum  Common Stock are issued and  outstanding,  (ii)  2,000,000
shares of  Syntroleum  Common  Stock  are  reserved  for  issuance  pursuant  to
Syntroleum's  1993  Stock  Option  and  Incentive  Plan and  189,939  shares  of
Syntroleum Common Stock (one

                                        8

percent  of the  number of shares of  Syntroleum  Common  Stock  outstanding  on
January 1, 1998) are reserved for issuance pursuant to Syntroleum's Stock Option
Plan for Outside  Directors  (Syntroleum's  1993 Stock Option and Incentive Plan
and  Syntroleum's  Stock  Option Plan for  Outside  Directors  are  collectively
referred to as the  "Syntroleum  Stock Option  Plans"),  (iii) 527,433 shares of
Syntroleum  Common Stock are issuable pursuant to outstanding and unvested stock
options  granted  pursuant to Syntroleum  Stock Option Plans,  200,001 shares of
Syntroleum  Common Stock are issuable  pursuant to outstanding  and vested stock
options granted  pursuant to Syntroleum  Stock Option Plans and 20,000 shares of
Syntroleum  Common Stock are issuable  pursuant to an  outstanding  and unvested
stock option granted to a consultant to Syntroleum  (the  "Consultant  Option");
(iv) no shares of Syntroleum Preferred Stock are issued and outstanding; and (v)
no bonds,  debentures,  notes or other indebtedness having the right to vote (or
convertible  into  securities  having the right to vote) on any matters on which
Syntroleum  stockholders  may vote  ("Syntroleum  Voting  Debt")  are  issued or
outstanding.  All outstanding  shares of Syntroleum  Common Stock have been duly
authorized, are validly issued, fully paid and nonassessable and are not subject
to  preemptive  rights.  Except as set forth on  Schedule  3.1(b) of  Syntroleum
Letter,  all  outstanding  shares  of  capital  stock  of  the  Subsidiaries  of
Syntroleum  are  owned by  Syntroleum,  or a direct  or  indirect  wholly  owned
Subsidiary of Syntroleum,  free and clear of all liens,  charges,  encumbrances,
claims and options of any nature.  Except as set forth in this Section 3.1(b) or
on Schedule  3.1(b) of Syntroleum  Letter and except for changes  resulting from
the exercise of employee  stock options  outstanding  on the date hereof granted
pursuant to Syntroleum Stock Option Plans, or as contemplated by this Agreement,
there are outstanding: (i) no shares of capital stock, Syntroleum Voting Debt or
other voting  securities of Syntroleum;  (ii) no securities of Syntroleum or any
Subsidiary of Syntroleum  convertible into or exchangeable for shares of capital
stock,  Syntroleum  Voting Debt or other voting  securities of Syntroleum or any
Subsidiary  of  Syntroleum;  and  (iii)  no  options,  warrants,  calls,  rights
(including preemptive rights),  commitments or agreements to which Syntroleum or
any  Subsidiary  of  Syntroleum  is a party  or by which it is bound in any case
obligating Syntroleum or any Subsidiary of Syntroleum to issue,  deliver,  sell,
purchase, redeem or acquire, or cause to be issued, delivered,  sold, purchased,
redeemed  or  acquired,  additional  shares of capital  stock or any  Syntroleum
Voting Debt or other voting  securities of  Syntroleum  or of any  Subsidiary of
Syntroleum,  or obligating  Syntroleum or any Subsidiary of Syntroleum to grant,
extend or enter  into any such  option,  warrant,  call,  right,  commitment  or
agreement.  Except as set forth on Schedule 3.1(b) of Syntroleum  Letter,  there
are no  stockholder  agreements,  registration  rights,  voting  trusts or other
similar  agreements or understandings to which Syntroleum is a party or by which
it is bound. Except as set forth on Schedule 3.1(b) of Syntroleum Letter,  there
are no restrictions on Syntroleum's ability to vote the stock held by Syntroleum
of any of its  Subsidiaries.  To the knowledge of Syntroleum,  as of the date of
this  Agreement,  no  stockholder of Syntroleum or "group" within the meaning of
Section  13(d)(3)  of the  Securities  Exchange  Act of 1934,  as  amended  (the
"Exchange  Act"),  will be  immediately  after the Effective Time the beneficial
owner of more than 25% of the then outstanding SLH Common Stock.

         (c)       Non-Subsidiaries  Equity  Investment.    Schedule  3.1(c)  of
Syntroleum Letter sets forth the book value of each investment by Syntroleum  or
any of its Subsidiaries in the voting securities, partnership interests or other
equity interests of any corporation, partnership or other entity (other

                                        9

than a Subsidiary of Syntroleum)  and the nature and percentage of  Syntroleum's
or its Subsidiaries' ownership interests in such investment. Except as set forth
in Schedule  3.1(c) of Syntroleum  Letter,  the voting  securities,  partnership
interests or other equity  interests of Syntroleum or its  Subsidiaries  in such
investments are owned free and clear of all liens, charges and encumbrances.

         (d)      Authority; No Violations; Consents and Approvals.

                  (i) The Board of  Directors  of  Syntroleum  has  approved the
         Merger and this Agreement,  by unanimous vote of the directors  (except
         for those  directors who  abstained),  and declared the Merger and this
         Agreement  to  be  in  the  best  interests  of  the   stockholders  of
         Syntroleum.  Syntroleum has all requisite corporate power and authority
         to enter into this Agreement and, subject, with respect to consummation
         of the  Merger,  to approval  of this  Agreement  and the Merger by the
         stockholders  of  Syntroleum  in  accordance  with the Oklahoma Act, to
         consummate  the  transactions  contemplated  hereby.  The execution and
         delivery of this  Agreement and the  consummation  of the  transactions
         contemplated   hereby  have  been  duly  authorized  by  all  necessary
         corporate  action on the part of Syntroleum,  subject,  with respect to
         consummation  of the  Merger,  to approval  of this  Agreement  and the
         Merger  by the  stockholders  of  Syntroleum  in  accordance  with  the
         Oklahoma  Act.  This  Agreement has been duly executed and delivered by
         Syntroleum and, subject, with respect to consummation of the Merger, to
         approval  of this  Agreement  and the  Merger  by the  stockholders  of
         Syntroleum  in  accordance  with the Oklahoma  Act,  and assuming  this
         Agreement   constitutes  the  valid  and  binding  obligation  of  SLH,
         constitutes a valid and binding obligation of Syntroleum enforceable in
         accordance  with  its  terms,   subject,   as  to  enforceability,   to
         bankruptcy,  insolvency,  reorganization  and  other  laws  of  general
         applicability relating to or affecting creditors' rights and to general
         principles of equity.

                  (ii)  Except as set  forth on  Schedule  3.1(d) of  Syntroleum
         Letter,  the execution and delivery of this Agreement does not, and the
         consummation  of the  transactions  contemplated  hereby and compliance
         with the  provisions  hereof will not,  conflict with, or result in any
         violation of, or default  (with or without  notice or 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, charge
         or  encumbrance  upon any of the  properties or assets of Syntroleum or
         any of its Subsidiaries  under, any provision of (i) the Certificate of
         Incorporation   or  Bylaws  of  Syntroleum  or  any  provision  of  the
         comparable   charter  or   organizational   documents  of  any  of  its
         Subsidiaries,  (ii) any loan or credit agreement, note, bond, mortgage,
         or indenture applicable to Syntroleum or any of its Subsidiaries, (iii)
         any other  agreement,  instrument,  permit,  concession,  franchise  or
         license  applicable to Syntroleum  or any of its  Subsidiaries  or (iv)
         assuming the consents, approvals, authorizations or permits and filings
         or notifications referred to in Section 3.1(d)(iii) are duly and timely
         obtained or made and the  approval of the Merger and this  Agreement by
         the stockholders of Syntroleum has been obtained, any judgment,  order,
         decree,  statute,  law,  ordinance,  rule or  regulation  applicable to
         Syntroleum  or any  of its  Subsidiaries  or  any of  their  respective
         properties or assets, other than, in the case

                                       10

         of clause (iii),  any such  conflicts,  violations,  defaults,  rights,
         liens, security interests,  charges or encumbrances that,  individually
         or in the  aggregate,  would  not have a  Syntroleum  Material  Adverse
         Effect,  materially  impair the  ability of  Syntroleum  to perform its
         obligations  hereunder  or  prevent  the  consummation  of  any  of the
         transactions contemplated hereby.

                  (iii) No  consent,  approval,  order or  authorization  of, or
         registration,  declaration  or filing  with,  or permit from any court,
         administrative agency or commission or other governmental  authority or
         instrumentality,  domestic  or foreign (a  "Governmental  Entity"),  is
         required by or with respect to Syntroleum or any of its Subsidiaries in
         connection  with  the  execution  and  delivery  of this  Agreement  by
         Syntroleum  or the  consummation  by  Syntroleum  of  the  transactions
         contemplated  hereby,  as to which the  failure to obtain or make would
         have a Syntroleum  Material Adverse Effect,  except for: (A) the filing
         of the  Certificate of Merger with the Secretary of States of the State
         of Oklahoma and Kansas;  and (B) such  filings and  approvals as may be
         required by any  applicable  state  securities,  "blue sky" or takeover
         laws.

         (e) Financial Statements.  Syntroleum previously has delivered to SLH a
true and complete copy of the consolidated  balance sheets of Syntroleum and its
consolidated  Subsidiaries  as of December  31,  1996 and 1997,  and the related
consolidated  statements of operations,  stockholders' equity and cash flows for
the fiscal years then ended on such dates,  together with the notes thereto,  in
each case  audited  by and  accompanied  by the report of Arthur  Andersen  LLP,
independent  accountants (all the foregoing financial statements,  including the
notes  thereto,  being  referred  to  herein  collectively  as  the  "Syntroleum
Financial Statements").  Syntroleum will deliver to SLH true and complete copies
of any quarterly financial statements (which will be prepared in the same manner
as Syntroleum Financial  Statements) prepared after the date hereof.  Syntroleum
Financial   Statements  are  prepared  in  accordance  with  generally  accepted
accounting  principles  in effect in the  United  States  ("GAAP")  applied on a
consistent  basis during the periods involved (except (i) as may be indicated in
the notes thereto, (ii) in the case of the unaudited financial statements,  such
differences  in  presentation  or  omissions  as  permitted  by  Rule  10-01  of
Regulation  S-X of the SEC and (iii) the unaudited  financial  statements do not
contain  all notes  required  by GAAP) and  fairly  present in  accordance  with
applicable requirements of GAAP (subject, in the case of the unaudited financial
statements,  to normal  year-end  adjustments  on a basis  comparable  with past
periods) the consolidated  financial position of Syntroleum and its consolidated
Subsidiaries  as of their  respective  dates  and the  consolidated  results  of
operations and the  consolidated  cash flows of Syntroleum and its  consolidated
Subsidiaries for the periods presented therein.

         (f) Information  Supplied.  None of the  information  supplied or to be
supplied by Syntroleum for inclusion or incorporation by reference in SLH's 1997
Form  10-K or the  Registration  Statement  on Form  S-4 to be  filed  with  the
Securities  and Exchange  Commission  (the "SEC") by SLH in connection  with the
issuance of shares of SLH Common  Stock in the Merger (the "S-4")  will,  at the
time the S-4 becomes effective under the Securities Act of 1933, as amended (the
"Securities Act"), and the rules and regulations  thereunder or at the Effective
Time (or in the case

                                       11

of SLH's Form 10-K,  upon filing  thereof),  contain any untrue  statement  of a
material fact or omit to state any material  fact required to be stated  therein
or  necessary to make the  statements  therein not  misleading,  and none of the
information   supplied  or  to  be  supplied  by  Syntroleum   and  included  or
incorporated by reference in the related proxy statement (the "Proxy Statement")
will,  at the time of  mailing  thereof  or at the time of the  meetings  of the
stockholders of SLH or Syntroleum to be held in connection with the Merger or at
the Effective Time,  contain any untrue  statement of a material fact or omit to
state any material fact  required to be stated  therein or necessary in order to
make the statements  therein, in light of the circumstances under which they are
made, not misleading.  If at any time prior to the Effective Time any event with
respect  to  Syntroleum  or any of its  Subsidiaries,  or with  respect to other
information  supplied by Syntroleum for inclusion in the Proxy Statement or S-4,
shall  occur  which  is  required  to be  described  in an  amendment  of,  or a
supplement to, the Proxy Statement or the S-4, such event shall be so described,
and such  amendment or supplement  shall be promptly  filed with the SEC and, as
required by law, disseminated to the stockholders of SLH and Syntroleum. The S-4
and  the  Proxy  Statement,   insofar  as  they  relate  to  Syntroleum  or  its
Subsidiaries or other information  supplied by Syntroleum for inclusion therein,
will  comply as to form in all  material  respects  with the  provisions  of the
Securities Act and the Exchange Act, and the rules and regulations thereunder.

         (g)  Absence of  Certain  Changes or  Events.  Except as  disclosed  in
Schedule  3.1(g)  of  Syntroleum  Letter,  or  except  as  contemplated  by this
Agreement,  since  December 31, 1997,  Syntroleum  has in all material  respects
conducted its business only in the ordinary  course and there has not been:  (i)
any declaration,  setting aside or payment of any dividend or other distribution
(whether in cash, stock or property) with respect to any of Syntroleum's capital
stock;  (ii)  any  amendment  of any  material  term of any  outstanding  equity
security of Syntroleum or any Subsidiary;  (iii) any  repurchase,  redemption or
other  acquisition by Syntroleum or any Subsidiary of any outstanding  shares of
capital stock or other equity  securities of, or other  ownership  interests in,
Syntroleum  or any  Subsidiary;  (iv)  any  material  change  in any  method  of
accounting or accounting practice, or in any tax method, principle,  election or
practice by Syntroleum or any  Subsidiary;  (v) if the covenants and  agreements
with respect to  Syntroleum  and its  Subsidiaries  set forth in Section 4.1 had
been  applicable  to  Syntroleum  and its  Subsidiaries  during the period  from
December  31,  1997 to the  date of this  Agreement,  any  action,  transaction,
commitment or failure to act that would cause  Syntroleum or any such Subsidiary
to fail to comply with such covenants and agreements;  or (vi) any other action,
transaction,  commitment,  dispute or other  event or  condition  (financial  or
otherwise) of any character  (whether or not in the ordinary course of business)
that has had,  or may  reasonably  be expected to have,  a  Syntroleum  Material
Adverse Effect.

         (h) No Undisclosed Material  Liabilities.  Except as fully reflected or
reserved  against  in  Syntroleum  Financial  Statements,  or  disclosed  in the
footnotes thereto,  or referred to in Schedule 3.1(h) or elsewhere in Syntroleum
Letter,  as  of  the  date  hereof  Syntroleum  and  its  Subsidiaries  have  no
liabilities,  absolute or contingent other than liabilities which,  individually
or in the aggregate,  are reasonably  expected not to have a Syntroleum Material
Adverse Effect.  Except as so reflected,  reserved or disclosed,  Syntroleum and
its Subsidiaries  have no commitments  which,  individually or in the aggregate,
are reasonably expected to have a Syntroleum Material Adverse Effect.

                                       12

         (i)      Material Contracts; No Defaults.

                  (i) Set forth in Schedule  3.1(i)(i) of  Syntroleum  Letter is
         (A) a list of all loan or credit agreements,  notes, bonds,  mortgages,
         indentures,  financing  leases or other debt  instruments or agreements
         pursuant to which, as of a date within 30 days of the date hereof,  any
         indebtedness  (determined in accordance with GAAP) of Syntroleum or any
         of its  Subsidiaries  in an  aggregate  principal  amount  in excess of
         $1,000,000  is  outstanding  or may be incurred and (B) the  respective
         principal  amounts  outstanding  thereunder  as of  the  date  of  this
         Agreement.

                  (ii)  Schedule  3.1(i)(ii)  of  Syntroleum  Letter  contains a
         listing   of  all  other   contracts,   agreements,   arrangements   or
         understandings  to which  Syntroleum  or one of its  Subsidiaries  is a
         party or by which any of them or any of their  properties  or assets is
         bound  (exclusive  of  any  contracts,   agreements,   arrangements  or
         understandings that are immaterial as to amount and significance to the
         operations  to which they  relate and are  routinely  entered  into the
         ordinary  course of  business)  described  in (A)  through (I) below to
         which  Syntroleum  or any of its  Subsidiaries  is a party  (the  items
         referred  to in  clauses  (i) and  (ii) of this  Section  3.1(i)  being
         collectively referred to herein as "Contracts").

                           (A)      Each Contract involving Syntroleum
                  Intangible Property;

                           (B) Each  Contract or guaranty of third party debt or
                  obligations not in the ordinary  course of business  involving
                  expenditures,  commitments or receipts of Syntroleum or any of
                  its Subsidiaries;

                           (C)  Each  lease,  rental  or  occupancy   agreement,
                  license, installment and conditional sale agreement, and other
                  Contract affecting the ownership of, leasing of, title to, use
                  of,  or any  leasehold  or  other  interest  in,  any  real or
                  personal property (except real or personal property leases and
                  installment and conditional  sales  agreements  having a value
                  per  property  or  item or  aggregate  payments  of less  than
                  $50,000 and with terms of less than one year);

                           (D) Each  Contract to or with any employee  providing
                  for  aggregate  payments in excess of $50,000 per year or with
                  any labor union or other employee representative of a group of
                  employees  relating to wages,  hours and other  conditions  of
                  employment;

                           (E)  Each   joint   venture   contract,   partnership
                  arrangement  or other  Contract  (however  named)  involving a
                  sharing of profits, losses, costs or liabilities by Syntroleum
                  or any of its Subsidiaries with any other person;

                                       13


                           (F) Each contract  containing  covenants which in any
                  way purport to limit the freedom of  Syntroleum  or any of its
                  Subsidiaries  to engage in any line of  business  or engage in
                  business in any geographic area or to compete with any person;

                           (G) Each  general  power  of  attorney  granting  the
                  recipient the power to commit material resources of Syntroleum
                  or  its   Subsidiaries   which  is  currently   effective  and
                  outstanding;

                           (H)      Each contract for  capital  expenditures  in
                  excess of $500,000; and

                           (I)  Each  amendment,   supplement  and  modification
                  (whether written or oral) in respect of any of the foregoing.

                  (iii)  Except  as  disclosed   on  Schedule   3.1(i)(iii)   of
         Syntroleum Letter (and, in the case of contracts and agreements arising
         after the date hereof and prior to the  Effective  Time,  which are not
         prohibited  by  Section  4.1 of this  Agreement  and are  disclosed  in
         writing to SLH),  there is no contract or agreement that is material to
         the  business,   financial   condition  or  results  of  operations  of
         Syntroleum and its Subsidiaries taken as a whole.  Neither  Syntroleum,
         nor any of its  Subsidiaries  is in default or violation  (and no event
         has  occurred  which,  with notice or the lapse of time or both,  would
         constitute a default or violation) of any term,  condition or provision
         of (i) in the case of Syntroleum and its Subsidiaries, their respective
         charter and bylaws or comparable  organizational documents, (ii) except
         as disclosed in Schedule 3.1(i) of Syntroleum  Letter,  any note, bond,
         mortgage,   indenture,   license,  agreement  or  other  instrument  or
         obligation  to which  Syntroleum  or any of its  Subsidiaries  is now a
         party or by which Syntroleum or any of its Subsidiaries or any of their
         respective  properties or assets may be bound or (iii) any order, writ,
         injunction,   decree,   statute,   rule  or  regulation  applicable  to
         Syntroleum or any of its  Subsidiaries,  except in the case of (ii) and
         (iii) for defaults or violations  which in the aggregate would not have
         a Syntroleum  Material Adverse Effect.  Except as disclosed on Schedule
         3.1(i)(iii) of Syntroleum Letter, to the knowledge of Syntroleum,  none
         of the other parties to the Contracts are in violation of or in default
         under (nor does there  exist any  condition  which upon the  passage of
         time or the giving of notice would cause such a violation of or default
         under) any  Contract,  other than such  violations or defaults as would
         not have a Syntroleum Material Adverse Effect.

         (j) Compliance with Applicable  Laws.  Syntroleum and its  Subsidiaries
hold all  permits,  licenses,  variances,  exemptions,  orders,  franchises  and
approvals of all Governmental Entities necessary for the lawful conduct of their
respective businesses (the "Syntroleum Permits"), except where the failure so to
hold would not have a Syntroleum  Material  Adverse  Effect.  Syntroleum and its
Subsidiaries  are in  compliance  with the terms of Syntroleum  Permits,  except
where the  failure so to comply  would not have a  Syntroleum  Material  Adverse
Effect. Except as disclosed or as set forth on Schedule 3.1(j),  3.1(k), 3.1(l),
3.1(m),  3.1(n) or 3.1(o) of Syntroleum Letter, the businesses of Syntroleum and
its Subsidiaries are not being conducted in violation of any law, ordinance,

                                       14

regulation,  judgment or decree of any Governmental Entity,  except for possible
violations which would not have a Syntroleum Material Adverse Effect.  Except as
set  forth on  Schedule  3.1(j)  of  Syntroleum  Letter,  as of the date of this
Agreement, no investigation or review by any Governmental Entity with respect to
Syntroleum or any of its  Subsidiaries  is, to the best knowledge of Syntroleum,
pending or  threatened,  other than those the  outcome of which would not have a
Syntroleum Material Adverse Effect.

         (k)  Litigation.  Schedule  3.1(k) of Syntroleum  Letter  discloses all
suits, actions or proceedings pending, or, to, the best knowledge of Syntroleum,
threatened  against  Syntroleum or any  Subsidiary  of  Syntroleum  ("Syntroleum
Litigation")  on  the  date  of  this  Agreement  and  all  judgments,  decrees,
injunctions,   rules  or  orders  of  any  Governmental   Entity  or  arbitrator
outstanding  against  Syntroleum or any  Subsidiary  of Syntroleum  ("Syntroleum
Order") on the date of this Agreement,  in each case in which the amount claimed
or that could be  involved  is in excess of  $100,000.  Except as  disclosed  on
Schedule 3.1(k) of Syntroleum  Letter,  there is no Syntroleum  Litigation that,
individually  or in the  aggregate  with all  other  Syntroleum  Litigation,  is
reasonably likely to have a Syntroleum Material Adverse Effect, nor is there any
Syntroleum  Order  that,  individually  or  in  the  aggregate  with  all  other
Syntroleum  Litigation,  is  reasonably  likely  to have a  Syntroleum  Material
Adverse Effect or a material  adverse effect on Syntroleum's  ability to perform
its obligations hereunder or to consummate the transactions contemplated by this
Agreement.

         (l) Taxes.  Except as set forth on Schedule 3.1(l) of Syntroleum Letter
and except for  exceptions to the following that would not,  individually  or in
the aggregate, have a Syntroleum Material Adverse Effect:

                  (i)  Each  of  Syntroleum,  each of its  Subsidiaries  and any
         affiliated,  consolidated,  combined, unitary or similar group of which
         any such corporation is or was a member has (A) duly and timely (taking
         into account any extensions) filed all federal,  state, local,  foreign
         and  other  returns,  declarations,   reports,  estimates,  information
         returns and statements  ("Returns")  required to be filed or sent by or
         with  respect to it in respect of any Taxes (as  hereinafter  defined),
         (B) duly paid or  deposited  on a timely  basis  all  Taxes  (including
         estimated Taxes) that are due and payable (except for audit adjustments
         not material in the aggregate or to the extent that liability  therefor
         is  reserved  for  in  Syntroleum's   most  recent  audited   financial
         statements)  for which  Syntroleum  or any of its  Subsidiaries  may be
         liable,  (C) established  reserves that are adequate for the payment of
         all  Taxes not yet due and  payable  with  respect  to the  results  of
         operations of Syntroleum and its Subsidiaries  through the date hereof,
         and (D) complied in all material  respects  with all  applicable  laws,
         rules and regulations  relating to the payment and withholding of Taxes
         and has in all material  respects  timely  withheld from employee wages
         and  paid  over to the  proper  governmental  authorities  all  amounts
         required to be so withheld and paid over.

                  (ii) Schedule  3.1(l) of Syntroleum  Letter sets forth (i) the
         last taxable  period through which the United States federal income Tax
         Returns of Syntroleum and any of its Subsidiaries have been examined by
         the Internal Revenue Service ("IRS") or otherwise

                                       15

         closed  and (ii) any  affiliated,  consolidated,  combined,  unitary or
         similar group Return in which  Syntroleum or any of its Subsidiaries is
         or has been a member or is or has joined in the  filing.  Except to the
         extent  being  contested  in  good  faith,  all  material  deficiencies
         asserted as a result of such  examinations  and any  examination by any
         applicable  federal,  state,  local,  foreign or other taxing authority
         have  been  paid,   fully  settled  or   adequately   provided  for  in
         Syntroleum's  most  recent  audited  financial  statements.  Except  as
         adequately provided for in Syntroleum Financial Statements, no material
         tax audits or other administrative proceedings or court proceedings are
         presently  pending with regard to any Taxes for which Syntroleum or any
         of its Subsidiaries would be liable, and no material deficiency for any
         such Taxes has been  proposed,  asserted or  assessed  pursuant to such
         examination  against  Syntroleum  or  any of  its  Subsidiaries  by any
         federal,  state, local,  foreign or other taxing authority with respect
         to any period.

                  (iii)  Neither  Syntroleum  nor  any of its  Subsidiaries  has
         executed or entered into with the IRS or any taxing  authority  (i) any
         agreement or other document extending or having the effect of extending
         the  period  for  assessments  or  collection  of any  Taxes  for which
         Syntroleum or any of its Subsidiaries would be liable or (ii) a closing
         agreement  pursuant  to Section  7121 of the Code,  or any  predecessor
         provision  thereof or any similar provision of federal,  state,  local,
         foreign or other tax law that  relates to the assets or  operations  of
         Syntroleum or any of its Subsidiaries.

                  (iv) Neither Syntroleum nor any of its Subsidiaries is a party
         to an agreement  that provides for the payment of any amount that would
         constitute a "parachute  payment" within the meaning of Section 280G of
         the Code.

                  (v) Neither Syntroleum nor any of its Subsidiaries has made an
         election  under  Section  341(f) of the Code or agreed to have  Section
         341(f)(2)  of the Code apply to any  disposition  of a  subsection  (f)
         asset (as such term is defined in Section  341(f)(4) of the Code) owned
         by Syntroleum or any of its Subsidiaries.

                  (vi) Neither Syntroleum nor any of its Subsidiaries is a party
         to,  is  bound  by or has  any  obligation  under  any tax  sharing  or
         allocation agreement or similar agreement or arrangement.

         For  purposes of this  Agreement,  "Taxes"  means all  federal,  state,
local, foreign and other taxes, charges, fees, levies, imposts, duties, licenses
or  other  governmental  assessments,  together  with any  interest,  penalties,
additions to tax or  additional  amounts  imposed by any taxing  authority  with
respect thereto.

                                       16

         (m)      Pension and Benefit Plans; ERISA.

                  (i) Syntroleum has made  available to SLH true,  correct,  and
         complete copies of each of the following which is sponsored, maintained
         or  contributed  to by  Syntroleum or any of its  Subsidiaries  for the
         benefit of the employees of Syntroleum or such Subsidiary:

                           (1) each  "employee  benefit  plan,"  as such term is
                  defined  in  Section  3(3)  of  the  United  States   Employee
                  Retirement  Income Security Act of 1974, as amended  ("ERISA")
                  (including,  but not limited to, employee benefit plans,  such
                  as foreign  plans,  which are not subject to the provisions of
                  ERISA) ("Syntroleum Plans"); and

                           (2)  each  personnel   policy,   stock  option  plan,
                  collective  bargaining  agreement,  bonus plan or arrangement,
                  incentive   award  plan  or  arrangement,   vacation   policy,
                  severance pay plan, policy or agreement, deferred compensation
                  agreement   or   arrangement,    executive   compensation   or
                  supplemental   income   arrangement,   consulting   agreement,
                  employment  agreement  and each other  employee  benefit plan,
                  agreement,  arrangement,  program,  practice or  understanding
                  which is not  described in Section  3.1(m)(i)(1)  ("Syntroleum
                  Benefit Programs").

                  (ii)     Except as disclosed in Schedule 3.1(m)(ii) of
         Syntroleum Letter:

                           (1) Syntroleum and its Subsidiaries do not contribute
                  to or have an obligation to contribute to, and have not at any
                  time within six years prior to the Effective Time  contributed
                  to or had an obligation to contribute to, a multiemployer plan
                  within the meaning of Section 3(37) of ERISA;

                           (2)    Syntroleum   and   its    Subsidiaries    have
                  substantially  performed  all  material  obligations,  whether
                  arising by  operation  of law or by  contract,  required to be
                  performed  by them in  connection  with  Syntroleum  Plans and
                  Syntroleum   Benefit   Programs,   and  to  the  knowledge  of
                  Syntroleum there have been no material  defaults or violations
                  by any other party to Syntroleum  Plans or Syntroleum  Benefit
                  Programs;

                           (3)  All   reports   and   disclosures   relating  to
                  Syntroleum  Plans  required to be filed with or  furnished  to
                  governmental   agencies,   Syntroleum  Plan   participants  or
                  beneficiaries  have been filed or furnished  substantially  in
                  accordance with applicable law in a timely manner;

                           (4) Each  Syntroleum  Plan  intended to be  qualified
                  under Section 401 of the Code  satisfies the  requirements  of
                  such Section and has received a favorable determination letter
                  from the Internal  Revenue  Service  regarding  such qualified
                  status and has not, since receipt of the most recent favorable
                  determination  letter,  been  amended or, to the  knowledge of
                  Syntroleum, operated in a way which would

                                       17

                  adversely affect such qualified  status.  As to any Syntroleum
                  Plan  intended to be qualified  under Section 401 of the Code,
                  there  has  been no  termination  or  partial  termination  of
                  Syntroleum Plan within the meaning of Section 411(d)(3) of the
                  Code;

                           (5) There  are no  actions,  suits or claims  pending
                  (other than routine  claims for benefits) or, to the knowledge
                  of Syntroleum,  threatened against, or with respect to, any of
                  Syntroleum  Plans  or  Syntroleum  Benefit  Programs  or their
                  assets.  To the  knowledge of  Syntroleum,  there is no matter
                  pending  (other  than  routine   qualification   determination
                  filings)  with respect to any of  Syntroleum  Plans before the
                  IRS,  the United  States  Department  of Labor or the  Pension
                  Benefit Guaranty Corporation ("PBGC");

                           (6) As to any Syntroleum  Plan subject to Title IV of
                  ERISA, there has been no event or condition which presents the
                  material risk of a Syntroleum Plan termination, no accumulated
                  funding deficiency,  whether or not waived, within the meaning
                  of Section  302 of ERISA or  Section  412 of the Code has been
                  incurred,  no  reportable  event within the meaning of Section
                  4043 of  ERISA  (for  which  the  disclosure  requirements  of
                  Regulation  2615.3  promulgated  by the  PBGC  have  not  been
                  waived)  has  occurred,  no  notice  of  intent  to  terminate
                  Syntroleum Plan has been given under Section 4041(c) of ERISA,
                  no proceeding has been instituted  under Section 4042 of ERISA
                  to  terminate  Syntroleum  Plan,  no liability to the PBGC has
                  been incurred;

                           (7) No act,  omission  or  transaction  has  occurred
                  which would result in  imposition  on Syntroleum or any of its
                  Subsidiaries  of (A) liability for a breach of fiduciary  duty
                  under  Section  409 of  ERISA,  (B) a civil  penalty  assessed
                  pursuant to subsection (c), (i) or (1) of Section 502 of ERISA
                  or (C) a tax  imposed  pursuant to Chapter 43 of Subtitle D of
                  the Code;

                           (8) With respect to any employee benefit plan, within
                  the  meaning  of  Section  3(3)  of  ERISA,  which  is  not  a
                  Syntroleum   Plan  but  which  is  sponsored,   maintained  or
                  contributed   to,  or  has  been   sponsored,   maintained  or
                  contributed  to within six years prior to the Effective  Time,
                  by any  corporation,  trade,  business or entity  under common
                  control with Syntroleum, within the meaning of Section 414(b),
                  (c) or (m) of the Code or Section  4001 of ERISA  ("Syntroleum
                  Commonly  Controlled  Entity"),  (A) no withdrawal  liability,
                  within  the  meaning  of  Section  4201  of  ERISA,  has  been
                  incurred,  which withdrawal  liability has not been satisfied,
                  (B)  no  liability  to  the  PBGC  has  been  incurred  by any
                  Syntroleum Commonly Controlled Entity, which liability has not
                  been satisfied, (C) no accumulated funding deficiency, whether
                  or not  waived,  within the meaning of Section 302 of ERISA or
                  Section  412 of the  Code  has  been  incurred,  and  (D)  all
                  contributions  (including  installments) to such plan required
                  by Section  302 of ERISA and Section 412 of the Code have been
                  timely made; and

                                      18

                           (9) The execution and delivery of this  Agreement and
                  the consummation of the transactions  contemplated hereby will
                  not (A) require  Syntroleum or any of its Subsidiaries to make
                  a larger  contribution  to, or pay greater benefits under, any
                  Syntroleum   Plan  or  Syntroleum   Benefit  Program  than  it
                  otherwise  would or (B) create or give rise to any  additional
                  vested rights or service  credits under any Syntroleum Plan or
                  Syntroleum Benefit Program.

                  (iii)  Except  as  disclosed   on  Schedule   3.1(m)(iii)   of
         Syntroleum  Letter,  there are no severance  agreements  or  employment
         agreements  between  Syntroleum  or  any of its  Subsidiaries  and  any
         employee of Syntroleum or such  Subsidiary.  True and correct copies of
         all such severance and employment agreements have been provided to SLH.
         Except as disclosed on Schedule  3.1(m)(iii) of Syntroleum  Letter, (A)
         neither  Syntroleum  nor any of its  Subsidiaries  has  any  consulting
         agreement or arrangement with any person involving annual  compensation
         in excess of $100,000,  except as are terminable  without  penalty upon
         one month's notice or less,  and (B) no stock or other security  issued
         by Syntroleum or any of its Subsidiaries forms or has formed a material
         part  of the  assets  of any  Syntroleum  Plan  or  Syntroleum  Benefit
         Program.

         (n)      Labor Matters.

                  (i) Except as set forth in Schedule  3.1(n)(i)  of  Syntroleum
         Letter,  as of  the  date  of  this  Agreement,  (1)  no  employees  of
         Syntroleum  or any of its  Subsidiaries  are  represented  by any labor
         organization;  (2) no  labor  organization  or group  of  employees  of
         Syntroleum  or any of its  Subsidiaries  has made a pending  demand for
         recognition  or  certification,  and  there  are no  representation  or
         certification   proceedings  or  petitions   seeking  a  representation
         proceeding  presently pending or threatened in writing to be brought or
         filed  with the  National  Labor  Relations  Board or any  other  labor
         relations   tribunal  or  authority;   and  (3)  to  the  knowledge  of
         Syntroleum,  there are no organizing activities involving Syntroleum or
         any of its Subsidiaries pending with any labor organization or group of
         employees of Syntroleum or any of its Subsidiaries.

                  (ii) Except as set forth on Schedule  3.1(n)(ii) of Syntroleum
         Letter,  Syntroleum and each of its  Subsidiaries is in compliance with
         all laws and orders relating to the employment of labor,  including all
         such laws and orders relating to wages, hours,  collective  bargaining,
         discrimination,  civil rights,  safety and health workers' compensation
         and the collection and payment of  withholding  and/or Social  Security
         Taxes and similar  Taxes,  except where the failure to comply would not
         have a Syntroleum Material Adverse Effect.

         (o) Intangible Property. To Syntroleum's knowledge,  Syntroleum and its
Subsidiaries  possess or have  adequate  rights to use all material  trademarks,
trade  names,  patents,  service  marks,  brand  marks,  brand  names,  computer
programs,   database,   industrial  designs,  trade  secrets,   technology,  and
copyrights  necessary for the operation of the  businesses of each of Syntroleum
and its  Subsidiaries  (collectively,  the  "Syntroleum  Intangible  Property"),
except where the failure to

                                       19

possess or have adequate rights to use such  properties  would not reasonably be
expected  to have a  Syntroleum  Material  Adverse  Effect.  Schedule  3.1(o) of
Syntroleum Letter lists all patents and trademarks (and applications for patents
and trademarks) or licensing agreements with respect to any patent or trademark,
which in each case is  applicable  to a  material  portion  of the  business  of
Syntroleum or its  Subsidiaries.  To the knowledge of Syntroleum,  except as set
forth on Schedule  3.1(o) of Syntroleum  Letter,  all of  Syntroleum  Intangible
Property is owned or used by  Syntroleum or its  Subsidiaries  free and clear of
any and all liens, claims or encumbrances,  except those that are not reasonably
likely to have a Syntroleum  Material Adverse Effect, and neither Syntroleum nor
any such  Subsidiary  has  forfeited or otherwise  relinquished  any  Syntroleum
Intangible  Property  which  forfeiture  would result in a  Syntroleum  Material
Adverse Effect. To the knowledge of Syntroleum, the use of Syntroleum Intangible
Property by Syntroleum or its  Subsidiaries  does not, in any material  respect,
conflict  with,  infringe  upon,  violate or  interfere  with or  constitute  an
appropriation  of any valid  right,  title,  interest  or  goodwill,  including,
without  limitation,  any intellectual  property right,  trademark,  trade name,
patent,  service  mark,  brand mark,  brand name,  computer  program,  database,
industrial design,  copyright or any pending  application  therefor of any other
person and there have been no claims made, and neither Syntroleum nor any of its
Subsidiaries has received any notice of any claim or otherwise  knows,  that any
of  Syntroleum  Intangible  Property is invalid or  conflicts  with the asserted
rights of any other  person or has not been used or  enforced or has been failed
to be used or  enforced  in a  manner  that  would  result  in the  abandonment,
cancellation  or  unenforceability  of any of  Syntroleum  Intangible  Property,
except for any such  conflict,  infringement,  violation,  interference,  claim,
invalidity,  abandonment,   cancellation  or  unenforceability  that  would  not
reasonably be expected to have a Syntroleum Material Adverse Effect.

         (p)      Environmental Matters.

                  For purposes of this Agreement:

                  (A) "Environmental Law" means any applicable law regulating or
         prohibiting  Releases  into any  part of the  natural  environment,  or
         pertaining to the protection of natural resources,  the Environment and
         public and employee health and safety  including,  without  limitation,
         the Comprehensive Environmental Response,  Compensation,  and Liability
         Act  ("CERCLA")  (42  U.S.C.  Section  9601  et  seq.),  the  Hazardous
         Materials  Transportation  Act (49 U. S. C. Section 1801 et seq.),  the
         Resource  Conservation  and  Recovery  Act (42 U.S.C.  Section  6901 et
         seq.), the Clean Water Act (33 U.S.C.  Section 1251 et seq.), the Clean
         Air Act (33 U.S.C.  Section 7401 et seq.), the Toxic Substances Control
         Act  (15  U.S.C.  Section  7401  et  seq.),  the  Federal  Insecticide,
         Fungicide,  and Rodenticide Act (7 U.S.C. Section 136 et seq.), and the
         Occupational  Safety and Health  Act (29  U.S.C.  Section  651 et seq.)
         ("OSHA") and the regulations promulgated pursuant thereto, and any such
         applicable  state or local statutes,  and the  regulations  promulgated
         pursuant  thereto,  as  such  laws  have  been  and may be  amended  or
         supplemented through the Closing Date.

                  (B)  "Hazardous  Material"  means any  substance,  material or
         waste  which is  regulated,  or which  could be the subject of Remedial
         Action, pursuant to any Environmental

                                       20

         Law by any public or  governmental  authority in the  jurisdictions  in
         which the applicable party or its Subsidiaries  conducts  business,  or
         the United  States,  including,  without  limitation,  any  material or
         substance  which  is  defined  as  a  "hazardous   waste,"   "hazardous
         material,"  "hazardous  substance,"  ("extremely  hazardous  waste"  or
         "restricted  hazardous  waste,"  "pollutant,"   "contaminants,"  "toxic
         waste" or "toxic substance" under any provision of Environmental Law;

                  (C) "Release" means any release,  spill,  effluent,  emission,
         leaking, pumping, injection, deposit, disposal,  discharge,  dispersal,
         leaching or migration into the indoor or outdoor  environment,  or into
         or out of any  property  owned,  operated  or leased by the  applicable
         party or its Subsidiaries; and

                  (D) "Remedial  Action" means all actions,  including,  without
         limitation, any capital expenditures, required by a governmental entity
         or required under any Environmental  Law, or voluntarily  undertaken to
         (I) clean up, remove, treat, or in any other way ameliorate the Release
         of any Hazardous Materials in the indoor or outdoor  environment;  (II)
         prevent  the  Release or threat of  Release,  or  minimize  the further
         Release of any  Hazardous  Material so it does not endanger or threaten
         to  endanger  the  public  health or  welfare  of the indoor or outdoor
         environment;  (III) perform  pre-remedial studies and investigations or
         post-remedial  monitoring and care pertaining or relating to a Release;
         or  (IV)  bring  the  applicable   party  into   compliance   with  any
         Environmental Law.

                           (i)  Except  as  disclosed  on  Schedule   3.1(p)  of
                  Syntroleum  Letter,  the  operations  of  Syntroleum  and  its
                  Subsidiaries  have been and are currently in  compliance  with
                  all Environmental  Laws, except where the failure to so comply
                  would not reasonably be expected to have a Syntroleum Material
                  Adverse Effect;

                           (ii)  Except  as  disclosed  on  Schedule  3.1(p)  of
                  Syntroleum  Letter,   Syntroleum  and  its  Subsidiaries  have
                  obtained and maintained all permits  required under applicable
                  Environmental  Laws  for the  continued  operations  of  their
                  respective  businesses,  except such permits the lack of which
                  would  not  reasonably  be  expected  to lead to a  Syntroleum
                  Material Adverse Effect;

                           (iii)  Except  as  disclosed  on  Schedule  3.1(p) of
                  Syntroleum  Letter,  as of the date hereof  Syntroleum and its
                  Subsidiaries are not subject to any material  (individually or
                  in the  aggregate)  outstanding  written  orders  or  material
                  contracts  with  any  Governmental   Entity  or  other  person
                  respecting (A) Environmental  Laws, (B) Remedial Action or (C)
                  any Release or threatened Release of a Hazardous Material;

                           (iv)  Except  as  disclosed  on  Schedule  3.1(p)  of
                  Syntroleum  Letter,  Syntroleum and its Subsidiaries  have not
                  received any written communication  alleging,  with respect to
                  any such party, and has no knowledge of, or reasonable

                                       21

                  reason to  suspect  the  existence  of,  the  violation  of or
                  liability  under any  Environmental  Law,  which  violation or
                  liability  would  reasonably  be expected to have a Syntroleum
                  Material Adverse Effect;

                           (v)  Except  as  disclosed  on  Schedule   3.1(p)  of
                  Syntroleum   Letter,   neither   Syntroleum  nor  any  of  its
                  Subsidiaries  has any contingent  liability in connection with
                  any  Release  of any  Hazardous  Material  including,  without
                  limitation,  in connection  with the exposure of any person or
                  property  to  Hazardous  Material  that  would  reasonably  be
                  expected to lead to a Syntroleum Material Adverse Effect;

                           (vi)  Except  as  disclosed  on  Schedule  3.1(p)  of
                  Syntroleum   Letter,  the  operations  of  Syntroleum  or  its
                  Subsidiaries   involving   the   generation,   transportation,
                  treatment,  storage or disposal of hazardous waste, as defined
                  and regulated  under 40 C.F.R.  Parts 260-270 (in effect as of
                  the date of this  Agreement) or any state  equivalent,  or any
                  other  Hazardous  Material are in compliance  with  applicable
                  Environmental  Laws,  except  where the  failure  to so comply
                  would not reasonably be expected to have a Syntroleum Material
                  Adverse Effect; and

                           (vii)  Except  as  disclosed  on  Schedule  3.1(p) of
                  Syntroleum  Letter,  to the  knowledge of Syntroleum as of the
                  date  hereof,  there  is  not  now on or in  any  property  of
                  Syntroleum or its Subsidiaries  any of the following:  (A) any
                  underground  storage  tanks or surface  impoundments,  (B) any
                  asbestos-containing  materials,  or  (C)  any  polychlorinated
                  biphenyls,  any of which  ((A),  (B) or (C)  preceding)  could
                  reasonably be expected to have a Syntroleum  Material  Adverse
                  Effect. None of the properties owned or operated by Syntroleum
                  are  restricted  as to use or as to transfer of title,  or the
                  subject of any  special  recorded  notice,  as a result of the
                  existence of Hazardous Substances thereon.

                           (viii)  Syntroleum  has  made  available  to SLH  for
                  review  all  written  reports  of  environmental   audits  and
                  assessments prepared for Syntroleum or any of its Subsidiaries
                  within  the last three  years by third  party  consultants  or
                  internal  environmental,  safety or health personnel which are
                  in the possession or control of Syntroleum and which relate to
                  the  assets  or   operations  of  Syntroleum  or  any  of  its
                  Subsidiaries.

         (q)      Opinion of Financial Advisor.   Syntroleum  has  received  the
opinion of J.P. Morgan Securities Inc. (a copy of which has  been  delivered  to
SLH) to the effect that, as of the date hereof, the consideration to be received
by the holders of Syntroleum Common Stock pursuant to  this  Agreement  is  fair
from a financial point of view to such holders.

         (r)      Vote Required.  The  affirmative  vote of  the  holders  of  a
majority of the shares of Syntroleum Common Stock outstanding is the  only  vote
of the holders of any class or series of

                                       22

Syntroleum   capital  stock   necessary  to  approve  this   Agreement  and  the
transactions contemplated hereby.

         (s) Insurance. Syntroleum has delivered to SLH an insurance schedule of
Syntroleum's and each of its  Subsidiaries'  directors' and officers'  liability
insurance,  primary and excess casualty insurance  policies,  providing coverage
for bodily  injury and  property  damage to third  parties,  including  products
liability and  completed  operations  coverage,  and worker's  compensation,  in
effect as of the date hereof. Syntroleum maintains insurance coverage reasonably
adequate  for the  operation  of the  business  of  Syntroleum  and  each of its
Subsidiaries  (taking into account the cost and availability of such insurance),
and the transactions  contemplated  hereby will not materially  adversely affect
such coverage.

         (t)  Brokers.  Except as  disclosed  on Schedule  3.1(t) of  Syntroleum
Letter,  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 Syntroleum.

         (u) Tax  Matters.  As of the date  hereof,  the  representations  which
Syntroleum  is to make  pursuant  to Exhibit C attached  hereto  (other than any
representation  which  refers  to the  Proxy  Statement)  are true and  correct,
assuming  for  purposes  of this  representation  and  warranty  that the Merger
referred  to in such  Exhibit  C had been  consummated  on the date  hereof.  In
addition,  the  representations  which  are  made by  Syntroleum  in the form of
Exhibit C hereof  (with such  variations  therein as may be made) in  connection
with the  rendering  of the tax opinion for which  provision  is made in Section
6.1(h) hereof will be true and correct at the time that the Merger occurs.  Such
representations are for the benefit of the holders of Syntroleum Common Stock.

         (v) Title. Except as disclosed in Syntroleum Financial Statements or on
Schedule 3.1(v) of Syntroleum  Letter,  Syntroleum and each of its  Subsidiaries
have  good  and  marketable  title to all real  property  and good  title to all
personal  property  owned by them,  in each case  free and  clear of all  liens,
pledges or encumbrances securing money borrowed,  the deferred purchase price of
property in excess of $300,000 or capital leases and free and clear of all other
liens,  pledges,  encumbrances  or defects  that  could  affect the value or use
thereof except for any such other liens,  pledges,  encumbrances or defects that
would not have a Syntroleum Material Adverse Effect.

         (w) Books and Records.  Syntroleum  and its  Subsidiaries  (i) make and
keep accurate books and records and (ii) maintain internal  accounting  controls
which  provide  reasonable  assurance  that (A)  transactions  are  executed  in
accordance with  management's  authorization,  (B)  transactions are recorded as
necessary to permit  preparation of their  financial  statements and to maintain
accountability for their assets, (C) access to their assets is permitted only in
accordance with management's  authorization and (D) the reported  accountability
for their assets is compared with existing assets at reasonable intervals.

                                       23

         (x) Certain Payments.  Neither  Syntroleum nor any of its Subsidiaries,
nor any director,  officer,  agent,  employee or other person associated with or
acting on  behalf of the  Syntroleum  or any of its  Subsidiaries,  has used any
corporate  funds for any unlawful  contribution,  gift,  entertainment  or other
unlawful  expense  relating to political  activity;  made any direct or indirect
unlawful  payment to any foreign or domestic  governmental  official or employee
from corporate funds; violated or is in violation of any provision of the United
States  Foreign  Corrupt  Practices  Act of 1977;  nor made any  illegal  bribe,
rebate, payoff, influence payment, kickback or other unlawful payment.

         (y) Transactions with Related Parties.  Except as set forth in Schedule
3.1(y)  of  Syntroleum  Letter,  there  are no  agreements,  contracts  or other
arrangements between (i) Syntroleum or any of its Subsidiaries, on the one hand,
and (ii) any Related Person (as defined below) of Syntroleum, on the other hand.
Except as set forth in Schedule  3.1(y) of Syntroleum  Letter and except for the
ownership of the SLH Common Stock  issued  hereunder,  after the Closing Date no
Related Person of Syntroleum  and no present  officer or director of any Related
Person  of  Syntroleum  has any  interest  in any  property  (real or  personal,
tangible or  intangible)  or contract  used in or  pertaining to the business of
Syntroleum  and  its  Subsidiaries   (or  the  Surviving   Corporation  and  its
Subsidiaries)  and no Related  Person of  Syntroleum  has any direct or indirect
ownership  interest  (excluding  immaterial  passive  investments) in any person
(other than through Syntroleum or any of its Subsidiaries) with which Syntroleum
or any of its  Subsidiaries  competes in any material  respect or has a material
business relationship. Schedule 3.1(y) of Syntroleum letter sets forth as of the
date of this  Agreement a  description  of all services  provided by any Related
Person of  Syntroleum  or  Syntroleum  and any of its  Subsidiaries.  A "Related
Person"  of any  person  shall  mean any holder of in excess of 5% of the equity
securities of such person and any  affiliates or associates  (as defined in Rule
12b-2 under the Exchange Act) of such holder (other than such original person or
its Subsidiaries).

         (z) State Takeover Laws.  Syntroleum has taken all necessary  action to
exempt the  transactions  contemplated  by this Agreement from the provisions of
Section 1090.3 of the Oklahoma Act, the Oklahoma Takeover Disclosure Act of 1985
and the Oklahoma Control Shares Acquisition Act.

         (aa) Year 2000. Syntroleum has taken all necessary action to enable its
computer  software to process data attributable to the year 2000 and thereafter.
Syntroleum's  operating and financial  systems will be able to process such data
by the year 2000.

         3.2      Representations and Warranties of SLH.    SLH  represents  and
warrants to Syntroleum as follows:

         (a)   Organization,   Standing  and  Power.   Each  of  SLH  and  SLH's
Subsidiaries  is a corporation,  partnership or limited  liability  company duly
organized,  validly  existing  and  in  good  standing  under  the  laws  of the
jurisdiction of its  incorporation or organization,  has all requisite power and
authority to own,  lease and operate its properties and to carry on its business
as now being

                                       24

conducted,  and is duly  qualified  and in good  standing to do business in each
jurisdiction in which the business it is conducting, or the operation, ownership
or leasing of its properties,  makes such qualification necessary, other than in
such  jurisdictions  where the failure to qualify  would not have a SLH Material
Adverse Effect (as defined  below).  SLH has heretofore  delivered to Syntroleum
complete and correct  copies of SLH's Articles of  Incorporation  and Bylaws and
the organizational documents of each of SLH's Subsidiaries.  All Subsidiaries of
SLH, the percentage of SLH's  ownership of such  Subsidiaries,  the identity and
percentage  ownership  of all  other  persons  with  equity  interests  in  such
Subsidiaries and their respective jurisdictions of incorporation or organization
are  identified  on  Schedule  3.2(a)  of the  letter  dated  and  delivered  to
Syntroleum  on the  date  hereof  (the  "SLH  Letter"),  which  relates  to this
Agreement  and is  designated  therein as being the SLH Letter.  As used in this
Agreement "SLH Material  Adverse Effect" or "SLH Material  Adverse Change" shall
mean any effect or change that is, individually or in the aggregate,  materially
adverse to the business,  operations, assets, condition (financial or otherwise)
or results of operation of SLH and its Subsidiaries  taken as a whole except for
general  economic  changes and changes that may affect the  industries of SLH or
any of its Subsidiaries generally.

         (b) Capital  Structure.  As of the date hereof,  the authorized capital
stock of SLH consists of 30,000,000  shares of SLH Common Stock,  par value $.01
per share,  and 1,000,000  shares of preferred  stock,  par value $.01 per share
("SLH  Preferred  Stock").  At the  close of  business  on March 12,  1998:  (i)
10,074,721  shares of SLH Common Stock are issued and outstanding,  an aggregate
of 974,400 shares of SLH Common Stock are reserved for issuance  pursuant to the
SLH Stock Option Plan,  780,000 shares of SLH Common Stock are issuable pursuant
to  outstanding  and unvested  stock options  granted  pursuant to the SLH Stock
Option  Plan and 194,400  shares of SLH Common  Stock are  issuable  pursuant to
outstanding  and vested stock options  granted  pursuant to the SLH Stock Option
Plan;  (ii) no shares of SLH  Preferred  Stock are  issued and  outstanding  and
50,000  shares of SLH  Junior  Preferred  Stock are  reserved  for  issuance  in
connection with the SLH Stock Purchase Rights;  and (iii) no bonds,  debentures,
notes or other  indebtedness  having  the  right  to vote (or  convertible  into
securities  having the right to vote) on any  matters on which SLH  stockholders
may vote ("SLH  Voting  Debt") are issued or  outstanding.  From March 12,  1998
until the Effective Time, no additional  shares,  options or similar rights will
be issued or  authorized  other than shares  issued in  connection  with options
which  were  outstanding  and vested  (or which  vest in  accordance  with their
original terms as in effect on the close of business on March 12, 1998) pursuant
to the SLH Stock  Option Plan as in effect on the close of business on March 12,
1998.  Assuming the Effective Date is prior to September 30, 1998, no options or
similar  rights  that were not vested at the close of business on March 12, 1998
will vest prior to the Effective  Time (other than in the case of the death of a
holder of such option or a change of control of SLH as provided in the SLH Stock
Option  Plan).  All  outstanding  shares  of SLH  Common  Stock  have  been duly
authorized, are validly issued, fully paid and nonassessable and are not subject
to preemptive  rights,  and,  subject to the approval of this  Agreement and the
Merger,  all  shares of SLH Common  Stock  issuable  in the Merger  will be duly
authorized  and,  when  issued,   will  be  validly   issued,   fully  paid  and
non-assessable  and free of preemptive  rights.  Except as set forth on Schedule
3.2(b)  of the SLH  Letter,  all  outstanding  shares  of  capital  stock of the
Subsidiaries  of SLH are owned by SLH,  or a direct  or  indirect  wholly  owned
Subsidiary of SLH, free and clear of all liens,  charges,  encumbrances,  claims
and  options of any  nature.  Except as set forth in this  Section  3.2(b) or on
Schedule 3.2(b) of the SLH Letter and except

                                       25

for changes resulting from the exercise of employee stock options outstanding on
the  date  hereof  granted  pursuant  to  the  SLH  Stock  Option  Plan,  or  as
contemplated by this Agreement there are  outstanding:  (i) no shares of capital
stock, SLH Voting Debt or other voting  securities of SLH; (ii) no securities of
SLH or any  Subsidiary of SLH  convertible  into or  exchangeable  for shares of
capital  stock,  SLH  Voting  Debt  or  other  voting  securities  of SLH or any
Subsidiary  of SLH; and (iii) no options,  warrants,  calls,  rights  (including
preemptive rights),  commitments or agreements to which SLH or any Subsidiary of
SLH is a party  or by  which  it is  bound  in any  case  obligating  SLH or any
Subsidiary of SLH to issue, deliver, sell, purchase, redeem or acquire, or cause
to be issued,  delivered,  sold,  purchased,  redeemed or  acquired,  additional
shares of capital stock or any SLH Voting Debt or other voting securities of SLH
or of any  Subsidiary  of SLH, or  obligating  SLH or any  Subsidiary  of SLH to
grant, extend or enter into any such option, warrant, call, right, commitment or
agreement.  Except as set forth on Schedule 3.2(b) of the SLH Letter,  there are
no stockholder  agreements,  registration rights, voting trusts or other similar
agreements  or  understandings  to which SLH is a party or by which it is bound.
Except  as set  forth  on  Schedule  3.2(b)  of the  SLH  Letter,  there  are no
restrictions  on  SLH's  ability  to vote  the  stock  held by SLH or any of its
Subsidiaries.  To the  knowledge  of SLH, as of the date of this  Agreement,  no
stockholder  of SLH or "group"  within the  meaning of Section  13(d)(3)  of the
Exchange Act will be immediately  after the Effective Time the beneficial  owner
of more than 25% of the then outstanding SLH Common Stock.

         (c)  Non-Subsidiaries  Equity  Investment.  Schedule  3.2(c) of the SLH
Letter  sets  forth the book value of each  investment  by the SLH or any of its
Subsidiaries  in the voting  securities,  partnership  interests or other equity
interests  of  any  corporation,  partnership  or  other  entity  (other  than a
Subsidiary of SLH) and the nature and  percentage of SLH's or its  Subsidiaries'
ownership  interests in such investment.  Except as set forth in Schedule 3.2(c)
of the SLH Letter, the voting securities,  partnership interests or other equity
interests  of SLH or its  Subsidiaries  in such  investments  are owned free and
clear of all liens, charges and encumbrances.

         (d)      Authority; No Violations; Consents and Approvals.

                  (i) The Board of Directors  of SLH has, by  unanimous  vote of
         the directors (except for those directors who abstained),  approved and
         declared to be in the best  interests  of the  stockholders  of SLH the
         Merger,   this   Agreement  and  the  amendments  to  the  Articles  of
         Incorporation of SLH provided in the Certificate of Merger. SLH has all
         requisite  corporate  power and authority to enter into this  Agreement
         and,  subject,  with respect to consummation of the Merger, to approval
         of  this  Agreement  and  the  Merger  by  the  stockholders  of SLH in
         accordance  with  the  Kansas  Code,  to  consummate  the  transactions
         contemplated  hereby.  The execution and delivery of this Agreement and
         the consummation of the transactions contemplated hereby have been duly
         authorized  by all  necessary  corporate  action  on the  part  of SLH,
         subject,  with respect to  consummation  of the Merger,  to approval of
         this Agreement and the Merger by the  stockholders of SLH in accordance
         with the  Kansas  Code.  This  Agreement  has been  duly  executed  and
         delivered  by SLH and,  subject,  with respect to  consummation  of the
         Merger, to approval of this Agreement and the Merger by

                                       26

         the  stockholders  of SLH in  accordance  with  the  Kansas  Code,  and
         assuming this Agreement constitutes the valid and binding obligation of
         Syntroleum,   constitutes  a  valid  and  binding   obligation  of  SLH
         enforceable   in   accordance   with   its   terms,   subject,   as  to
         enforceability,  to bankruptcy,  insolvency,  reorganization  and other
         laws of  general  applicability  relating  to or  affecting  creditors'
         rights and to general principles of equity.

                  (ii) Except as set forth on Schedule 3.2(d) of the SLH Letter,
         the  execution  and  delivery  of  this  Agreement  does  not,  and the
         consummation  of the  transactions  contemplated  hereby and compliance
         with the  provisions  hereof will not,  conflict with, or result in any
         violation of, or default  (with or without  notice or 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, charge
         or  encumbrance  upon any of the  properties or assets of SLH or any of
         its   Subsidiaries   under,  any  provision  of  (i)  the  Articles  of
         Incorporation  or  Bylaws  of SLH or any  provision  of the  comparable
         charter or organizational  documents of any of its  Subsidiaries,  (ii)
         any loan or  credit  agreement,  note,  bond,  mortgage,  or  indenture
         applicable  to  SLH  or  any  of  its  Subsidiaries,  (iii)  any  other
         agreement,   instrument,  permit,  concession,   franchise  or  license
         applicable  to SLH or any of its  Subsidiaries  or  (iv)  assuming  the
         consents,   approvals,   authorizations   or  permits  and  filings  or
         notifications  referred to in Section  3.2(d)(iii)  are duly and timely
         obtained or made and the approval of this  Agreement  and the Merger by
         the stockholders of SLH has been obtained, any judgment, order, decree,
         statute, law, ordinance, rule or regulation applicable to SLH or any of
         its Subsidiaries or any of their respective properties or assets, other
         than,  in the case of clause  (iii),  any such  conflicts,  violations,
         defaults,  rights, liens,  security interests,  charges or encumbrances
         that,  individually or in the aggregate,  would not have a SLH Material
         Adverse  Effect,  materially  impair the  ability of SLH to perform its
         obligations  hereunder  or  prevent  the  consummation  of  any  of the
         transactions contemplated hereby.

                  (iii) No  consent,  approval,  order or  authorization  of, or
         registration,   declaration   or  filing  with,   or  permit  from  any
         Governmental Entity is required by or with respect to SLH or any of its
         Subsidiaries  in  connection  with the  execution  and delivery of this
         Agreement  by  SLH  or the  consummation  by  SLH  of the  transactions
         contemplated  hereby,  as to which the  failure to obtain or make would
         have a SLH Material Adverse Effect, except for: (A) the filing with the
         SEC of a proxy statement in preliminary and definitive form relating to
         the meeting of SLH's  stockholders  to be held in  connection  with the
         approval of this Agreement and the Merger by  stockholders  of SLH, the
         S-4,  such  reports  under  Section  13(a) of the Exchange Act and such
         other  compliance  with the Securities Act and the Exchange Act and the
         rules and regulations  thereunder as may be required in connection with
         this  Agreement  and  the  transactions  contemplated  hereby,  and the
         obtaining  from  the  SEC of such  orders  as may be so  required;  (B)
         filings  with,  and  approval  of, the Nasdaq  Stock  Market;  (C) such
         filings  and  approvals  as may be  required  by any  applicable  state
         securities, "blue sky" or takeover laws, or environmental laws; and (D)
         the filing of the  Certificate of Merger with the Secretary of State of
         the States of Oklahoma and Kansas.

                                       27

         (e) SEC  Documents.  SLH has made  available  to  Syntroleum a true and
complete copy of each quarterly,  annual or current report on Form 10-Q, 10-K or
8-K, registration statement and definitive proxy statement filed by SLH with the
SEC prior to the date of this Agreement, which are all the documents (other than
preliminary  material)  that SLH was  required to file with the SEC prior to the
date of this  Agreement.  SLH will  make  available  to  Syntroleum,  a true and
complete copy of each quarterly,  annual or current report on Form 10-Q, 10-K or
8-K, registration statement and definitive proxy statement filed by SLH with the
SEC  subsequent to the date of this  Agreement and prior to the Effective  Time.
All of such reports and statements filed prior to the date of this Agreement and
the Form 10-K of the SLH are hereinafter referred to as the "SLH SEC Documents."
As of their  respective  filing  dates,  the SLH SEC  Documents  complied in all
material  respects with the  requirements  of the Securities Act or the Exchange
Act,  as the case may be, and the rules and  regulations  of the SEC  thereunder
applicable to such SLH SEC Documents,  and, assuming the accuracy of information
supplied by  Syntroleum  for  inclusion  therein,  none of the SLH SEC Documents
contained any untrue statement of a material fact or omitted to state a material
fact required to be stated therein or necessary to make the statements  therein,
in light of the circumstances under which they were made, not misleading.  As of
their respective  filing dates, the financial  statements of SLH included in the
SLH SEC  Documents  complied  as to  form  in all  material  respects  with  the
published rules and regulations of the SEC with respect  thereto,  were prepared
in  accordance  with GAAP  applied on a  consistent  basis  during  the  periods
involved (except (i) as may be indicated in the notes thereto,  (ii) in the case
of the unaudited  statements,  such  differences in presentation or omissions as
permitted  by Rule 10-01 of  Regulation  S-X of the SEC and (iii) the  unaudited
financial  statements  do not  contain  all notes  required  by GAAP) and fairly
presented in accordance  with applicable  requirements of GAAP (subject,  in the
case of the unaudited  statements,  to normal  year-end  adjustments  on a basis
comparable with past periods) the consolidated financial position of SLH and its
consolidated  Subsidiaries  as of their  respective  dates and the  consolidated
results  of  operations  and  the  consolidated   cash  flows  of  SLH  and  its
consolidated Subsidiaries for the periods presented therein.

         (f) Information Supplied. Assuming the accuracy of information supplied
by Syntroleum for inclusion therein,  none of the information  supplied or to be
supplied by SLH for inclusion or  incorporation by reference in the S-4 will, at
the time the S-4 becomes  effective under the Securities Act or at the Effective
Time,  contain  any untrue  statement  of a  material  fact or omit to state any
material fact required to be stated  therein or necessary to make the statements
therein not misleading,  and none of the information  supplied or to be supplied
by SLH and included or incorporated by reference in the Proxy Statement will, at
the time of mailing  thereof or at the time of the meetings of the  stockholders
of SLH or  Syntroleum  to be  held  in  connection  with  the  Merger  or at the
Effective Time, contain any untrue statement of a material fact or omit to state
any material  fact  required to be stated  therein or necessary in order to make
the statements therein, in light of the circumstances under which they are made,
not  misleading.  If at any time  prior to the  Effective  Time any  event  with
respect to SLH or any of its Subsidiaries,  or with respect to other information
supplied by SLH for inclusion in the Proxy  Statement or S-4,  shall occur which
is required to be

                                       28

described in an amendment  of, or a  supplement  to, the Proxy  Statement or the
S-4, such event shall be so described, and such amendment or supplement shall be
promptly  filed  with the SEC  and,  as  required  by law,  disseminated  to the
stockholders of SLH and Syntroleum. The S-4 and the Proxy Statement,  insofar as
they relate to SLH or its Subsidiaries or other information  supplied by SLH for
inclusion  therein,  will comply as to form in all  material  respects  with the
provisions of the Exchange Act and the rules and regulations thereunder.

         (g) Absence of Certain  Changes or Events.  Except as disclosed  in, or
reflected in the  financial  statements  included in the SLH SEC Documents or on
Schedule 3.2(g) of the SLH Letter,  or except as contemplated by this Agreement,
since  December  31,  1997,  SLH has, in all material  respects,  conducted  its
business  only  in  the  ordinary  course  and  there  has  not  been:  (i)  any
declaration,  setting  aside or payment of any  dividend  or other  distribution
(whether in cash,  stock or property) with respect to any of SLH's capital stock
(other  than a two for one stock split  effected on February 9, 1998);  (ii) any
amendment of any material term of any outstanding  equity security of SLH or any
Subsidiary; (iii) any repurchase,  redemption or other acquisition by SLH or any
Subsidiary of any outstanding shares of capital stock or other equity securities
of,  or  other  ownership  interests  in,  SLH  or  any  Subsidiary,  except  as
contemplated by SLH Benefit Programs (as hereinafter defined); (iv) any material
change in any method of accounting or accounting practice, or in any tax method,
principle,  election or practice by SLH or any Subsidiary;  (v) if the covenants
and agreements with respect to the SLH and its Subsidiaries set forth in Section
4.2 had been  applicable  to SLH and its  Subsidiaries  during the  period  from
December  31,  1997 to the  date of this  Agreement,  any  action,  transaction,
commitment or failure to act that would cause SLH or any such Subsidiary to fail
to  comply  with  such  covenants  and  agreements;  or (vi) any  other  action,
transaction,  commitment,  dispute or other  event or  condition  (financial  or
otherwise) of any character  (whether or not in the ordinary course of business)
that has had, or may  reasonably  be expected to have,  a SLH  Material  Adverse
Effect,  except for general  economic  changes  and changes  that may affect the
industries of SLH or any of its Subsidiaries generally.

         (h) No Undisclosed Material  Liabilities.  Except as fully reflected or
reserved against in the financial  statements included in the SLH SEC Documents,
or  disclosed in the  footnotes  thereto,  or referred to in Schedule  3.2(h) or
elsewhere in the SLH Letter, as of the date hereof SLH and its Subsidiaries have
no  liabilities,   absolute  or  contingent   other  than   liabilities   which,
individually  or in the  aggregate,  are  reasonably  expected not to have a SLH
Material Adverse Effect. Except as so reflected,  reserved or disclosed, SLH and
its Subsidiaries  have no commitments  which,  individually or in the aggregate,
are reasonably expected to have a SLH Material Adverse Effect.

         (i) Material Contracts;  No Defaults.  All of the material contracts of
SLH and its  Subsidiaries  that  are  required  to be  described  in the SLH SEC
Documents  or to be filed as exhibits  thereto,  or that would be required to be
described  or filed if a Form 10-K with  respect to the SLH were  required to be
filed on the date hereof,  have been described or filed in the SLH SEC Documents
except as disclosed on Schedule 3.2(i) of the SLH Letter. Neither SLH nor any of
its  Subsidiaries  is in  violation  of or in  default  under  (and no event has
occurred  which,  with notice or the lapse of time or both,  would  constitute a
default or violation) of any term, condition or provision of (i) in the

                                       29

case of SLH and its  Significant  Subsidiaries,  their  respective  charter  and
bylaws or  comparable  organizational  documents,  (ii) except as  disclosed  in
Schedule 3.2(i) of the SLH Letter, any note, bond, mortgage, indenture, license,
agreement  or  other  instrument  or  obligation  to  which  SLH  or  any of its
Subsidiaries is now a party or by which SLH or any of its Subsidiaries or any of
their  respective  properties  or assets may be bound or (iii) any order,  writ,
injunction,  decree, statute, rule or regulation applicable to SLH or any of its
Subsidiaries,  except in the case of (ii) and (iii) for  defaults or  violations
which in the aggregate would not have a SLH Material  Adverse  Effect.  Schedule
3.2(i) of the SLH Letter lists each contract  containing  covenants which in any
way purport to limit the freedom of SLH or any of its  Subsidiaries to engage in
any line of business or engage in business in any geographic  area or to compete
with any person.  Except as disclosed on Schedule  3.2(i) of the SLH Letter,  to
the knowledge of SLH, none of the other parties to material  contracts of SLH or
its  Subsidiaries  are in violation of or in default under (nor does there exist
any condition which upon the passage of time or the giving of notice would cause
such a violation of or default under) any contract,  other than such  violations
or defaults as would not have a SLH Material Adverse Effect.

         (j) Compliance with Applicable Laws. SLH and its Subsidiaries  hold all
permits, licenses,  variances,  exemptions,  orders, franchises and approvals of
all Governmental  Entities  necessary for the lawful conduct of their respective
businesses  (the "SLH  Permits"),  except where the failure so to hold would not
have a SLH Material  Adverse Effect.  SLH and its Subsidiaries are in compliance
with the terms of the SLH  Permits,  except where the failure so to comply would
not have a SLH Material  Adverse Effect.  Except as disclosed or as set forth on
Schedule 3.2(j),  3.2(k), 3.2(l), 3.2(m), 3.2(n) or 3.2(p) of the SLH Letter the
businesses of SLH and its  Subsidiaries  are not being conducted in violation of
any law, ordinance,  regulation,  judgment or decree of any Governmental Entity,
except for  possible  violations  which  would not have a SLH  Material  Adverse
Effect. Except as set forth on Schedule 3.2(j) of the SLH Letter, as of the date
of this Agreement,  no investigation  or review by any Governmental  Entity with
respect  to SLH or any of its  Subsidiaries  is, to the best  knowledge  of SLH,
pending or  threatened,  other than those the  outcome of which would not have a
SLH Material Adverse Effect.

         (k) Litigation.  Schedule 3.2(k) of the SLH Letter discloses all suits,
actions or proceedings  pending,  or, to, the best knowledge of SLH,  threatened
against  SLH or any  Subsidiary  of SLH ("SLH  Litigation")  on the date of this
Agreement  and all  judgments,  decrees,  injunctions,  rules or  orders  of any
Governmental  Entity or arbitrator  outstanding against SLH or any Subsidiary of
SLH  ("SLH  Order")  on the date of this  Agreement,  in each  case in which the
amount  claimed or that could be  involved is in excess of  $100,000.  Except as
disclosed on Schedule 3.2(k) of the SLH Letter, there is no SLH Litigation that,
individually  or in the aggregate with all other SLH  Litigation,  is reasonably
likely to have a SLH Material  Adverse Effect,  nor is there any SLH Order that,
individually  or in the aggregate with all other SLH  Litigation,  is reasonably
likely to have a SLH Material  Adverse  Effect or a material  adverse  effect on
SLH's  ability  to  perform  its  obligations  hereunder  or to  consummate  the
transactions contemplated by this Agreement.

                                       30

         (l) Taxes. Except as set forth on Schedule 3.2(1) of the SLH Letter and
except for  exceptions to the following that would not,  individually  or in the
aggregate, have a SLH Material Adverse Effect:

                  (i) Each of SLH, each of its  Subsidiaries and any affiliated,
         consolidated,  combined,  unitary  or  similar  group of which any such
         corporation  is or was a member  has (A) duly and timely  (taking  into
         account any extensions) filed all federal,  state,  local,  foreign and
         other Returns  required to be filed or sent by or with respect to it in
         respect of any Taxes,  (B) duly paid or deposited on a timely basis all
         Taxes (including  estimated Taxes) that are due and payable (except for
         audit  adjustments  not material in the aggregate or to the extent that
         liability  therefor  is  reserved  for in  SLH's  most  recent  audited
         financial  statements) for which SLH or any of its  Subsidiaries may be
         liable,  (C) established  reserves that are adequate for the payment of
         all  Taxes not yet due and  payable  with  respect  to the  results  of
         operations of SLH and its Subsidiaries through the date hereof, and (D)
         complied in all material  respects with all applicable  laws, rules and
         regulations relating to the payment and withholding of Taxes and has in
         all material respects timely withheld from employee wages and paid over
         to the proper  governmental  authorities all amounts  required to be so
         withheld and paid over.

                  (ii) Schedule 3.2(l) of the SLH Letter sets forth (i) the last
         taxable  period  through  which the United  States  federal  income Tax
         Returns of SLH and any of its  Subsidiaries  have been  examined by the
         IRS  or  otherwise  closed  and  (ii)  any  affiliated,   consolidated,
         combined,  unitary or similar  group  Return in which the SLH or any of
         its  Subsidiaries  is or has been a member  or is or has  joined in the
         filing.  Except  to the  extent  being  contested  in good  faith,  all
         material deficiencies asserted as a result of such examinations and any
         examination by any applicable federal,  state, local,  foreign or other
         taxing authority have been paid,  fully settled or adequately  provided
         for in SLH's  most  recent  audited  financial  statements.  Except  as
         adequately provided for in the financial statements included in the SLH
         SEC  Documents,   no  material  tax  audits  or  other   administrative
         proceedings or court  proceedings are presently  pending with regard to
         any Taxes for which SLH or any of its Subsidiaries would be liable, and
         no material  deficiency for any such Taxes has been proposed,  asserted
         or  assessed  pursuant  to such  examination  against SLH or any of its
         Subsidiaries  by any  federal,  state,  local,  foreign or other taxing
         authority with respect to any period.

                  (iii) Neither SLH nor any of its  Subsidiaries has executed or
         entered into with the IRS or any taxing  authority (i) any agreement or
         other  document  extending or having the effect of extending the period
         for  assessments or collection of any Taxes for which SLH or any of its
         Subsidiaries  would be liable or (ii) a closing  agreement  pursuant to
         Section 7121 of the Code, or any predecessor  provision  thereof or any
         similar provision of federal,  state,  local,  foreign or other tax law
         that  relates  to  the  assets  or  operations  of  SLH  or  any of its
         Subsidiaries.

                                       31

                  (iv) Neither SLH nor any of its  Subsidiaries is a party to an
         agreement  that  provides  for the  payment  of any  amount  that would
         constitute a "parachute  payment" within the meaning of Section 280G of
         the Code.

                  (v)  Neither  SLH  nor  any of its  Subsidiaries  has  made an
         election  under  Section  341(f) of the Code or agreed to have  Section
         341(f)(2)  of the Code apply to any  disposition  of a  subsection  (f)
         asset (as such term is defined in Section  341(f)(4) of the Code) owned
         by SLH or any of its Subsidiaries.

                  (vi) Neither SLH nor any of its Subsidiaries is a party to, is
         bound by or has any  obligation  under any tax  sharing  or  allocation
         agreement or similar agreement or arrangement.

         (m)      Pension and Benefit Plans; ERISA.

                  (i) SLH has made available to Syntroleum  true,  correct,  and
         complete copies of each of the following which is sponsored, maintained
         or contributed to by SLH or any of its  Subsidiaries for the benefit of
         the employees of SLH or such Subsidiary:

                           (1) each  "employee  benefit  plan,"  as such term is
                  defined in Section 3(3) of ERISA,  including,  but not limited
                  to, employee benefit plans,  such as foreign plans,  which are
                  not subject to the provisions of ERISA ("SLH Plans"); and

                           (2)  each  personnel   policy,   stock  option  plan,
                  collective  bargaining  agreement,  bonus plan or arrangement,
                  incentive   award  plan  or  arrangement,   vacation   policy,
                  severance pay plan, policy or agreement, deferred compensation
                  agreement   or   arrangement,    executive   compensation   or
                  supplemental   income   arrangement,   consulting   agreement,
                  employment  agreement  and each other  employee  benefit plan,
                  agreement,  arrangement,  program,  practice or  understanding
                  which is not described in Section  3.2(m)(i)(l)  ("SLH Benefit
                  Programs").

                  (ii)     Except as disclosed in Schedule 3.2(m)(ii) of the SLH
         Letter:

                           (1) SLH and its  Subsidiaries do not contribute to or
                  have an obligation to contribute  to, and have not at any time
                  within six years prior to the Effective Time contributed to or
                  had an  obligation  to  contribute  to, a  multiemployer  plan
                  within the meaning of Section 3(37) of ERISA;

                           (2)  SLH  and  its  Subsidiaries  have  substantially
                  performed  all  material   obligations,   whether  arising  by
                  operation of law or by  contract,  required to be performed by
                  them in  connection  with the SLH  Plans  and the SLH  Benefit
                  Programs,  and to the  knowledge  of SLH  there  have  been no
                  material  defaults or violations by any other party to the SLH
                  Plans or SLH Benefit Programs;

                                       32

                           (3) All reports and  disclosures  relating to the SLH
                  Plans  required to be filed with or furnished to  governmental
                  agencies,  SLH Plan  participants or  beneficiaries  have been
                  filed or furnished substantially in accordance with applicable
                  law in a timely manner;

                           (4) Each  SLH Plan  intended  to be  qualified  under
                  Section 401 of the Code  satisfies  the  requirements  of such
                  Section and has received a favorable determination letter from
                  the Internal  Revenue Service  regarding such qualified status
                  and has  not,  since  receipt  of the  most  recent  favorable
                  determination  letter,  been  amended or, to the  knowledge of
                  SLH,  operated  in a way which  would  adversely  affect  such
                  qualified  status. As to any SLH Plan intended to be qualified
                  under Section 401 of the Code,  there has been no  termination
                  or partial  termination  of the SLH Plan within the meaning of
                  Section 411(d)(3) of the Code;

                           (5) There  are no  actions,  suits or claims  pending
                  (other than routine  claims for benefits) or, to the knowledge
                  of SLH, threatened against, or with respect to, any of the SLH
                  Plans  or  SLH  Benefit  Programs  or  their  assets.  To  the
                  knowledge  of SLH,  there is no  matter  pending  (other  than
                  routine qualification  determination  filings) with respect to
                  any of the  SLH  Plans  before  the  IRS,  the  United  States
                  Department of Labor or the PBGC;

                           (6) As to any SLH Plan  subject to Title IV of ERISA,
                  there  has been no  event  or  condition  which  presents  the
                  material  risk  of a  SLH  Plan  termination,  no  accumulated
                  funding deficiency,  whether or not waived, within the meaning
                  of Section  302 of ERISA or  Section  412 of the Code has been
                  incurred,  no  reportable  event within the meaning of Section
                  4043 of  ERISA  (for  which  the  disclosure  requirements  of
                  Regulation  2615.3  promulgated  by the  PBGC  have  not  been
                  waived) has occurred, no notice of intent to terminate the SLH
                  Plain has been  given  under  Section  4041(c)  of  ERISA,  no
                  proceeding has been instituted  under Section 4042 of ERISA to
                  terminate  the SLH  Plan,  no  liability  to the PBGC has been
                  incurred;

                           (7) No act,  omission  or  transaction  has  occurred
                  which  would  result  in  imposition  on  SLH  or  any  of its
                  Subsidiaries  of (A) liability for a breach of fiduciary  duty
                  under  Section  409 of  ERISA,  (B) a civil  penalty  assessed
                  pursuant  to  subsections  (c),  (i) or (1) of Section  502 of
                  ERISA or (C) a tax imposed  pursuant to Chapter 43 of Subtitle
                  D of the Code;

                           (8) With respect to any employee benefit plan, within
                  the meaning of Section 3(3) of ERISA,  which is not a SLH Plan
                  but which is sponsored,  maintained or contributed  to, or has
                  been sponsored,  maintained or contributed to within six years
                  prior  to  the  Effective  Time,  by any  corporation,  trade,
                  business or entity under common  control with SLH,  within the
                  meaning of Section  414(b),  (c) or (m) of the Code or Section
                  4001 of ERISA ("SLH Commonly Controlled Entity"), (A) no

                                       33

                  withdrawal  liability,  within the meaning of Section  4201 of
                  ERISA, has been incurred,  which withdrawal  liability has not
                  been satisfied, (B) no liability to the PBGC has been incurred
                  by any SLH Commonly Controlled Entity, which liability has not
                  been satisfied, (C) no accumulated funding deficiency, whether
                  or not  waived,  within the meaning of Section 302 of ERISA or
                  Section  412 of the  Code  has  been  incurred,  and  (D)  all
                  contributions  (including  installments) to such plan required
                  by Section  302 of ERISA and Section 412 of the Code have been
                  timely made; and

                           (9) The execution and delivery of this  Agreement and
                  the consummation of the transactions  contemplated hereby will
                  not  (A)  require  SLH or any of its  Subsidiaries  to  make a
                  larger contribution to, or pay greater benefits under, any SLH
                  Plan or SLH Benefit  Program  than it  otherwise  would or (B)
                  create or give rise to any additional vested rights or service
                  credits under any SLH Plan or SLH Benefit Program.

                  (iii) Except as disclosed on Schedule  3.2(m)(iii)  of the SLH
         Letter,  there are no severance  agreements  or  employment  agreements
         between SLH or any of its  Subsidiaries and any employee of SLH or such
         Subsidiary.   True  and  correct  copies  of  all  such  severance  and
         employment  agreements  have been  provided  to  Syntroleum.  Except as
         disclosed on Schedule  3.2(m)(iii)  of the SLH Letter,  (A) neither SLH
         nor any of its Subsidiaries has any consulting agreement or arrangement
         with any person  involving  annual  compensation in excess of $100,000,
         except as are  terminable  without  penalty upon one month's  notice or
         less,  and (B) no stock or other  security  issued by SLH or any of its
         Subsidiaries  forms or has formed a material  part of the assets of any
         SLH Plan or SLH Benefit Program.

         (n)      Labor Matters.

                  (i)  Except  as set  forth in  Schedule  3.2(n)(i)  of the SLH
         Letter,  as of the date of this  Agreement,  (1) no employees of SLH or
         any of its Subsidiaries are represented by any labor organization;  (2)
         no  labor  organization  or  group  of  employees  of SLH or any of its
         Subsidiaries   has  made  a   pending   demand   for   recognition   or
         certification,   and  there  are  no  representation  or  certification
         proceedings or petitions seeking a representation  proceeding presently
         pending  or  threatened  in  writing  to be  brought  or filed with the
         National Labor Relations Board or any other labor relations tribunal or
         authority;  and (3) to the  knowledge of SLH,  there are no  organizing
         activities  involving SLH or any of its  Subsidiaries  pending with any
         labor  organization  or  group  of  employees  of  SLH  or  any  of its
         Subsidiaries.

                  (ii)  Except as set forth on  Schedule  3.2(n)(ii)  of the SLH
         Letter, SLH and each of its Subsidiaries is in compliance with all laws
         and orders relating to the employment of labor, including all such laws
         and  orders   relating   to  wages,   hours,   collective   bargaining,
         discrimination,  civil rights,  safety and health workers' compensation
         and the collection and payment of  withholding  and/or Social  Security
         Taxes and similar  Taxes,  except where the failure to comply would not
         have a SLH Material Adverse Effect.

                                       34

         (o)  Intangible  Property.  SLH and its  Subsidiaries  possess  or have
adequate rights to use all material trademarks,  trade names,  patents,  service
marks, brand marks, brand names, computer programs, database, industrial designs
and copyrights  necessary for the operation of the businesses of each of SLH and
its Subsidiaries (collectively, the "SLH Intangible Property"), except where the
failure to  possess or have  adequate  rights to use such  properties  would not
reasonably be expected to have a SLH Material  Adverse  Effect.  Schedule 3.2(o)
lists all patents and  trademarks  or licensing  agreements  with respect to any
patent or trademark,  which in each case is applicable to a material  portion of
the  business of SLH or its  Subsidiaries  and the failure to possess  would not
reasonably be expected to have a SLH Material  Adverse Effect.  To the knowledge
of SLH, except as set forth on Schedule 3.2(o) of the SLH Letter, all of the SLH
Intangible  Property is owned by SLH or its  Subsidiaries  free and clear of any
and all liens,  claims or  encumbrances,  except  those that are not  reasonably
likely to have a SLH  Material  Adverse  Effect,  and  neither  SLH nor any such
Subsidiary has forfeited or otherwise  relinquished any SLH Intangible  Property
which forfeiture would result in a SLH Material Adverse Effect. To the knowledge
of SLH, the use of SLH Intangible  Property by SLH or its Subsidiaries does not,
in any material respect, conflict with, infringe upon, violate or interfere with
or  constitute  an  appropriation  of any right,  title,  interest or  goodwill,
including, without limitation, any intellectual property right, trademark, trade
name, patent, service mark, brand mark, brand name, computer program,  database,
industrial design,  copyright or any pending  application  therefor of any other
person  and  there  have  been no  claims  made and  neither  SLH nor any of its
Subsidiaries has received any notice of any claim or otherwise knows that any of
SLH Intangible  Property is invalid or conflicts with the asserted rights of any
other  person or has not been used or  enforced or has been failed to be used or
enforced  in a manner  that would  result in the  abandonment,  cancellation  or
unenforceability  of  any  of SLH  Intangible  Property,  except  for  any  such
conflict, infringement, violation, interference, claim, invalidity, abandonment,
cancellation or unenforceability that would not reasonably be expected to have a
SLH Material Adverse Effect.

         (p)      Environmental Matters.

                  (i) Except as disclosed on Schedule  3.2(p) of the SLH Letter,
         the operations of SLH and its Subsidiaries  have been and are currently
         in compliance with all Environmental  Laws, except where the failure to
         so comply  would not  reasonably  be  expected  to have a SLH  Material
         Adverse Effect;

                  (ii) Except as disclosed on Schedule 3.2(p) of the SLH Letter,
         SLH and its  Subsidiaries  have  obtained  and  maintained  all permits
         required  under  applicable   Environmental   Laws  for  the  continued
         operations of their respective businesses, except such permits the lack
         of which would not  reasonably  be  expected to lead to a SLH  Material
         Adverse Effect;

                  (iii)  Except  as  disclosed  on  Schedule  3.2(p)  of the SLH
         Letter,  as of the date hereof SLH and its Subsidiaries are not subject
         to any material  (individually or in the aggregate) outstanding written
         orders or material contracts with any Governmental Entity

                                       35

         or other person respecting (A) Environmental  Laws, (B) Remedial Action
         or (C) any Release or threatened Release of a Hazardous Material;

                  (iv) Except as disclosed on Schedule 3.2(p) of the SLH Letter,
         SLH and its  Subsidiaries  have not received any written  communication
         alleging,  with respect to any such party,  and has no knowledge of, or
         reasonable  reason to suspect the  existence  of, the  violation  of or
         liability  under any  Environmental  Law, which  violation or liability
         would reasonably be expected to have a SLH Material Adverse Effect;

                  (v) Except as disclosed on Schedule  3.2(p) of the SLH Letter,
         neither SLH nor any of its Subsidiaries has any contingent liability in
         connection  with  any  Release  of any  Hazardous  Material  including,
         without  limitation,  in connection  with the exposure of any person or
         property to Hazardous  Material  that would  reasonably  be expected to
         lead to a SLH Material Adverse Effect;

                  (vi) Except as disclosed on Schedule 3.2(p) of the SLH Letter,
         the  operations of SLH or its  Subsidiaries  involving the  generation,
         transportation,  treatment,  storage or disposal of hazardous waste, as
         defined and  regulated  under 40 C.F.R.  Parts 260-270 (in effect as of
         the date of this  Agreement)  or any  state  equivalent,  or any  other
         Hazardous  Material are in  compliance  with  applicable  Environmental
         Laws,  except  where the failure to so comply would not  reasonably  be
         expected to have a SLH Material Adverse Effect; and

                  (vii)  Except  as  disclosed  on  Schedule  3.2(p)  of the SLH
         Letter, to the knowledge of SLH as of the date hereof, there is not now
         on or in any property of SLH or its  Subsidiaries any of the following:
         (A) any  underground  storage  tanks or surface  impoundments,  (B) any
         asbestos-containing  materials,  or (C) any polychlorinated  biphenyls,
         any of which ((A), (B) or (C) preceding)  could  reasonably be expected
         to have a SLH Material Adverse Effect.  None of the properties owned or
         operated by SLH are restricted as to use or as to transfer of title, or
         the  subject  of  any  special  recorded  notice,  as a  result  of the
         existence of Hazardous Substances thereon.

                  (viii) SLH has made  available  to  Syntroleum  for review all
         written reports of  environmental  audits and assessments  prepared for
         SLH or any of its  Subsidiaries  within the last  three  years by third
         party consultants or internal environmental, safety or health personnel
         which are in the  possession  or control of SLH and which relate to the
         assets or operations of SLH or any of its Subsidiaries.

         (q)      Opinion of Financial Advisor.  SLH has received the opinion of
Salomon Smith Barney (a copy of which has been delivered to Syntroleum)  to  the
effect that, as of the date hereof, the Exchange Ratio is fair  to  SLH  from  a
financial point of view.

                                       36

         (r) Vote Required. The affirmative vote of the holders of a majority of
the  outstanding  shares of SLH Common  Stock is the only vote of the holders of
any class or series of SLH capital stock necessary to approve this Agreement and
the Merger and the transactions contemplated hereby.

         (s) Insurance. SLH has delivered to Syntroleum an insurance schedule of
SLH's  and  each  of  its  Subsidiaries'   directors'  and  officers'  liability
insurance,  primary and excess casualty insurance  policies,  providing coverage
for bodily  injury and  property  damage to third  parties,  including  products
liability and  completed  operations  coverage,  and worker's  compensation,  in
effect  as of the date  hereof.  SLH  maintains  insurance  coverage  reasonably
adequate for the  operation of the business of SLH and each of its  Subsidiaries
(taking  into  account the cost and  availability  of such  insurance),  and the
transactions  contemplated  hereby  will not  materially  adversely  affect such
coverage.

         (t) Brokers.  Except as disclosed on Schedule 3.2(t) of the SLH Letter,
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
SLH.

         (u) Tax Matters. As of the date hereof, the  representations  which SLH
is to make pursuant to Exhibit C attached hereto (other than any  representation
which refers to the Proxy Statement) are true and correct, assuming for purposes
of this  representation and warranty that the Merger referred to in such Exhibit
C had been  consummated  on the date hereof.  In addition,  the  representations
which are made by SLH in the form of  Exhibit  C hereof  (with  such  variations
therein as may be made) in connection  with the rendering of the tax opinion for
which provision is made in Section 6.1(h) hereof will be true and correct at the
time that the Merger  occurs.  Such  representations  are for the benefit of the
holders of Syntroleum Common Stock.

         (v) Title.  Except as disclosed in the SLH  Financial  Statements or on
Schedule  3.2(v) of the SLH Letter,  the SLH and each of its  Subsidiaries  have
good and  marketable  title to all real  property and good title to all personal
property  owned by them,  in each case free and clear of all  liens,  pledges or
encumbrances securing money borrowed, the deferred purchase price of property in
excess of  $300,000  or capital  leases  and free and clear of all other  liens,
pledges,  encumbrances  or defects  that could  affect the value or use  thereof
except for any such other liens, pledges, encumbrances or defects that would not
have a SLH Material Adverse Effect.

         (w) Books and Records.  The SLH and its  Subsidiaries (i) make and keep
accurate books and records and (ii) maintain internal  accounting controls which
provide  reasonable  assurance that (A)  transactions are executed in accordance
with management's  authorization,  (B) transactions are recorded as necessary to
permit preparation of their financial statements and to maintain  accountability
for their  assets,  (C) access to their assets is permitted  only in  accordance
with management's  authorization and (D) the reported  accountability  for their
assets is compared with existing assets at reasonable intervals.

                                       37

         (x) Certain Payments. Neither the SLH nor any of its Subsidiaries,  nor
any director, officer, agent, employee or other person associated with or acting
on behalf of the SLH or any of its  Subsidiaries,  has used any corporate  funds
for any unlawful  contribution,  gift,  entertainment  or other unlawful expense
relating to political activity;  made any direct or indirect unlawful payment to
any foreign or domestic  governmental official or employee from corporate funds;
violated or is in violation of any  provision of the Foreign  Corrupt  Practices
Act of 1977;  nor made any illegal bribe,  rebate,  payoff,  influence  payment,
kickback or other unlawful payment.

         (y) Transactions with Related Parties.  Except as set forth in Schedule
3.2(y) of the SLH Letter or in the SLH SEC  Documents,  there are no agreements,
contracts or other arrangements  between (i) SLH or any of its Subsidiaries,  on
the one hand, and (ii) any Related  Person of SLH, on the other hand.  Except as
set forth in  Schedule  3.2(y) of the SLH  Letter,  after  the  Closing  Date no
Related  Person of SLH and no present  officer or director of any Related Person
of SLH  has  any  interest  in any  property  (real  or  personal,  tangible  or
intangible) or contract used in or pertaining to the business of the SLH and its
Subsidiaries (or the Surviving  Corporation and its Subsidiaries) and no Related
Person  of  SLH  has  any  direct  or  indirect  ownership  interest  (excluding
immaterial passive  investments) in any person (other than through SLH or any of
its  Subsidiaries)  with which SLH or any of its  Subsidiaries  competes  in any
material  respect  or has a  material  business  relationship.  Other than those
services  described in the SLH SEC Documents,  Schedule 3.2(y) of the SLH Letter
sets  forth as of the  date of this  Agreement  a  description  of all  services
provided by any Related Person of SLH to SLH and any of its Subsidiaries.

         (z)  State  Takeover  Laws  and SLH  Rights  Plan.  SLH has  taken  all
necessary action to exempt the transactions  contemplated by this Agreement from
the provisions of Section 17.12.101 of the Kansas Code and Sections 1286 through
1298 of the Kansas Code. The  transactions  contemplated  by this Agreement will
not cause the SLH Stock Purchase Rights to become exercisable.

         (aa)  Year  2000.  SLH has  taken all  necessary  action to enable  its
computer  software to process data attributable to the year 2000 and thereafter.
SLH's  operating and financial  systems will be able to process such data by the
year 2000.


                                   ARTICLE IV

                    COVENANTS RELATING TO CONDUCT OF BUSINESS

         4.1 Conduct of Business by  Syntroleum  Pending the Merger.  During the
period from the date of this Agreement and continuing  until the Effective Time,
Syntroleum  agrees as to itself and its  Subsidiaries  that (except as expressly
contemplated  or  permitted by this  Agreement,  or to the extent that SLH shall
otherwise consent in writing):

                                       38

         (a)  Ordinary  Course.   Except  as  provided  on  Schedule  4.1(a)  of
Syntroleum  Letter,  each of Syntroleum and its Subsidiaries  shall carry on its
businesses only in the usual,  regular and ordinary course in substantially  the
same manner as heretofore  conducted and shall use all  commercially  reasonable
efforts to preserve intact its present  business  organizations,  keep available
the services of its current officers and employees, and endeavor to preserve its
relationships with customers, suppliers and others having business dealings with
it to the end that its  goodwill and ongoing  business  shall not be impaired in
any material respect at the Effective Time.

         (b) Dividends;  Changes in Stock. Except as provided on Schedule 4.1(b)
of Syntroleum  Letter,  Syntroleum  shall not and it shall not permit any of its
Subsidiaries to: (i) declare or pay any dividends on or make other distributions
in respect of any of its capital stock,  except for the  declaration and payment
of dividends from a Subsidiary of Syntroleum to Syntroleum or another Subsidiary
of Syntroleum  and except for cash  dividends or  distributions  paid on or with
respect to the capital stock of a Subsidiary of Syntroleum;  (ii) split, combine
or  reclassify  any of its capital  stock or issue or  authorize  or propose the
issuance of any other  securities  in respect of, in lieu of or in  substitution
for  shares of its  capital  stock;  or (iii)  repurchase,  redeem or  otherwise
acquire,  or permit any of its  Subsidiaries  to  purchase,  redeem or otherwise
acquire, any shares of its capital stock, except as required by the terms of its
securities  outstanding  on the date  hereof,  as  contemplated  by any existing
employee  benefit  plan or  program  or  pursuant  to the terms of any  existing
agreements  with  employees  of  Syntroleum  and  its   Subsidiaries   upon  the
termination of employment of any such employee.

         (c) Issuance of  Securities.  Except as provided on Schedule  4.1(c) of
Syntroleum  Letter,  Syntroleum  shall  not and it shall not  permit  any of its
Subsidiaries  to,  issue,  deliver or sell,  or  authorize  or propose to issue,
deliver or sell,  any shares of its capital stock of any class,  any Voting Debt
or any  securities  convertible  into,  or any  rights,  warrants  or options to
acquire, any such shares, Voting Debt or convertible securities, other than: (i)
the  issuance of  Syntroleum  Common  Stock upon the  exercise of stock  options
granted under  Syntroleum  Stock Option Plans that are  outstanding  on the date
hereof,  or in  satisfaction of stock grants or stock based awards made prior to
the date hereof pursuant to Syntroleum Stock Option Plans; and (ii) issuances by
a wholly owned Subsidiary of its capital stock to its parent.

         (d)      Governing Documents.  Except  as  contemplated  hereby  or  in
connection herewith,  Syntroleum  shall  not  amend  or  propose  to  amend  its
Certificate of Incorporation or Bylaws.

         (e) No Acquisitions.  Other than acquisitions listed on Schedule 4.1(e)
of Syntroleum  Letter,  Syntroleum  shall not and it shall not permit any of its
Subsidiaries to, acquire or agree to acquire by merging or,  consolidating with,
or by purchasing a substantial  equity  interest in or a substantial  portion of
the  assets  of,  or by any  other  manner,  any  business  or any  corporation,
partnership, association or other business organization or division thereof.

         (f)      No Dispositions.  Other than:  (i)  dispositions  or  proposed
dispositions listed on Schedule 4.1(f) of Syntroleum  Letter;  (ii)  as  may  be
necessary or required by law to consummate

                                       39

the transactions contemplated hereby; or (iii) dispositions of other assets that
are not  material,  individually  or in the  aggregate,  to  Syntroleum  and its
Subsidiaries taken as a whole,  Syntroleum shall not and it shall not permit any
of its Subsidiaries to sell,  lease,  encumber or otherwise dispose of, or agree
to sell,  lease (whether such lease is an operating or capital lease),  encumber
or otherwise dispose of, any of its assets.  Notwithstanding the foregoing, none
of Syntroleum  nor its  Subsidiaries  shall sell,  lease,  encumber or otherwise
dispose  of, or agree to dispose  of, any of its  assets to any  Related  Person
other than in the ordinary course of business on an arms length basis.

         (g) No Dissolution,  Etc. Except as otherwise permitted or contemplated
by this  Agreement,  Syntroleum  shall  not  authorize,  recommend,  propose  or
announce an  intention  to adopt a plan of complete  or partial  liquidation  or
dissolution of Syntroleum or any of its Significant Subsidiaries.

         (h) Certain Employee Matters. Except as set forth on Schedule 4.1(h) of
Syntroleum  Letter,  Syntroleum  shall  not and it shall not  permit  any of its
Subsidiaries  to:  (i) grant any  increases  in the  compensation  of any of its
directors,  officers or employees,  except  increases in the ordinary  course of
business  and in  accordance  with past  practice;  (ii) pay or agree to pay any
pension,  retirement  allowance  or  other  employee  benefit  not  required  or
contemplated by any of the existing  Syntroleum  Benefit  Programs or Syntroleum
Plans as in effect on the date hereof to any such director, officer or employee,
whether  past or  present;  (iii)  enter  into any new,  or amend any  existing,
employment or severance or termination agreement with any such director, officer
or key  employee;  or (iv) become  obligated  under any new  Syntroleum  Benefit
Program or Syntroleum  Plan, which was not in existence or approved by the Board
of Directors  of  Syntroleum  prior to or on the date hereof,  or amend any such
plan or arrangement in existence on the date hereof if such amendment would have
the effect of materially enhancing any benefits thereunder.

         (i) Indebtedness;  Leases; Capital Expenditures. Except as set forth on
Schedule 4.1(i) of Syntroleum Letter, Syntroleum shall not, nor shall Syntroleum
permit any of its Subsidiaries to, (i) incur any indebtedness for borrowed money
or  guarantee  any such  indebtedness  or issue or sell any debt  securities  or
warrants  or rights to acquire any debt  securities  of such party or any of its
Subsidiaries  or guarantee  any debt  securities  of others,  (ii) except in the
ordinary  course of  business,  enter into any lease  (whether  such lease is an
operating or capital lease) or create any mortgages,  liens,  security interests
or other  encumbrances on the property of Syntroleum or any of its  Subsidiaries
in connection with any indebtedness thereof,  except for those securing purchase
money  indebtedness or (iii) commit to aggregate capital  expenditures in excess
of $100,000  outside the capital budget,  as approved by Syntroleum prior to the
date hereof and set forth on Schedule 4.1(i) of Syntroleum Letter.

         (j) No  Solicitation.  From and after the date hereof,  Syntroleum will
not, and will not authorize or permit any of its officers, directors, employees,
agents  and  other   representatives   or  those  of  any  of  its  Subsidiaries
(collectively, "Syntroleum Representatives") to, directly or indirectly, solicit
or  initiate  any  prospective   buyer  or  the  making  of  any  proposal  that
constitutes,  or may reasonably be expected to lead to, a Syntroleum Acquisition
Proposal (as defined herein) from any

                                       40

person;  provided,  however,  that,  notwithstanding any other provision of this
Agreement, (i) Syntroleum may engage in discussions or negotiations with a third
party who (without any solicitation or initiation, directly or indirectly, by or
with  Syntroleum  or any  Syntroleum  Representatives  after  the  date  of this
Agreement)  seeks to initiate such  discussions or negotiations  and may furnish
such third party information concerning Syntroleum and its business,  properties
and  assets,  (ii)  Syntroleum's  Board of  Directors  may take and  disclose to
Syntroleum's  stockholders a position  contemplated by Rule 14e-2(a) promulgated
under the Exchange Act and (iii) following  receipt of a Syntroleum  Acquisition
Proposal that is financially  superior to the Merger and  reasonably  capable of
being financed (as determined in each case in good faith by  Syntroleum's  Board
of Directors after consultation with Syntroleum's financial advisors), the Board
of Directors of Syntroleum may withdraw,  modify or not make its  recommendation
referred  to in Section 5.5 or  terminate  this  Agreement  in  accordance  with
Section  7.1(b),  but in each case  referred  to in the  foregoing  clauses  (i)
through (iii) only to the extent that the Board of Directors of Syntroleum shall
conclude in good faith that such action is  necessary  in order for the Board of
Directors of Syntroleum to act in a manner that is consistent with its fiduciary
obligations  under applicable law.  Syntroleum shall immediately cease and cause
to be terminated any existing solicitation, initiation, encouragement, activity,
discussion or negotiation with any parties conducted heretofore by Syntroleum or
any  Syntroleum  Representatives  with  respect  to any  Syntroleum  Acquisition
Proposal existing on the date hereof. Syntroleum will promptly notify SLH of any
such requests for such information or the receipt of any Syntroleum  Acquisition
Proposal,  including  the  identity  of the  person  or group  engaging  in such
discussions  or  negotiations,   requesting  such  information  or  making  such
Syntroleum   Acquisition  Proposal,  and  (unless  the  Board  of  Directors  of
Syntroleum   concludes  such  disclosure  is  inconsistent  with  its  fiduciary
obligations  under  applicable  law) the material  terms and  conditions  of any
Syntroleum  Acquisition  Proposal.  As  used  in  this  Agreement,   "Syntroleum
Acquisition Proposal" shall mean any proposal or offer, other than a proposal or
offer by SLH or any of its affiliates, for a tender or exchange offer, a merger,
consolidation  or  other  business  combination   involving  Syntroleum  or  any
Subsidiary  of Syntroleum or any proposal to acquire in any manner a substantial
equity interest in, or substantially  all of the assets of, Syntroleum or any of
its Subsidiaries.

         4.2 Conduct of  Business  by SLH Pending the Merger.  During the period
from the date of this  Agreement and  continuing  until the Effective  Time, SLH
agrees as to itself and its Subsidiaries that (except as expressly  contemplated
or permitted by this Agreement, or to the extent that Syntroleum shall otherwise
consent in writing):

         (a) Ordinary  Course.  Except as provided on Schedule 4.2(a) of the SLH
Letter,  except as  contemplated  by  Section  5.16  hereof  and  except for the
execution  prior to the Closing  Date of a  consulting  and  sublease  agreement
between SLH and Lab Holdings, Inc. in form and substance reasonably satisfactory
to Syntroleum,  each of SLH and its  Subsidiaries  shall carry on its businesses
only in the usual,  regular and ordinary course in substantially the same manner
as heretofore  conducted and shall use all  commercially  reasonable  efforts to
preserve intact its present business organizations,  keep available the services
of  its  current   officers  and   employees,   and  endeavor  to  preserve  its
relationships with customers, suppliers and others having business dealings with
it to

                                       41

the end that its  goodwill  and  ongoing  business  shall not be impaired in any
material respect at the Effective Time.

         (b) Dividends;  Changes in Stock. Except as provided on Schedule 4.2(b)
of the SLH Letter, SLH shall not and it shall not permit any of its Subsidiaries
to: (i) declare or pay any dividends on or make other  distributions  in respect
of any of its capital stock, except for the declaration and payment of dividends
from a Subsidiary of SLH to SLH or another Subsidiary of SLH and except for cash
dividends or  distributions  paid on or with  respect to the capital  stock of a
Subsidiary of SLH; (ii) split, combine or reclassify any of its capital stock or
issue or authorize or propose the  issuance of any other  securities  in respect
of, in lieu of or in  substitution  for shares of its  capital  stock;  or (iii)
repurchase,  redeem or otherwise  acquire,  or permit any of its Subsidiaries to
purchase,  redeem or otherwise acquire,  any shares of its capital stock, except
as required by the terms of its securities  outstanding  on the date hereof,  as
contemplated by any existing employee benefit plan or program or pursuant to the
terms of any existing agreements with employees of SLH and its Subsidiaries upon
the termination of employment of any such employee.

         (c) Issuance of  Securities.  Except as provided on Schedule  4.2(c) of
the SLH  Letter,  SLH shall not and it shall not permit any of its  Subsidiaries
to, issue,  deliver or sell, or authorize or propose to issue,  deliver or sell,
any shares of its capital stock of any class,  any Voting Debt or any securities
convertible  into,  or any  rights,  warrants  or options to  acquire,  any such
shares, Voting Debt or convertible  securities,  other than: (i) the issuance of
SLH Common  Stock upon the  exercise of stock  options  granted  under SLH Stock
Option Plans that are  outstanding  on the date hereof,  or in  satisfaction  of
stock grants or stock based awards made prior to the date hereof pursuant to SLH
Stock Option  Plans;  and (ii)  issuances by a wholly  owned  Subsidiary  of its
capital stock to its parent.

         (d) Governing Documents. Except as contemplated hereby or in connection
herewith,  SLH shall not amend or propose to amend its Articles of Incorporation
or Bylaws;  provided that prior to the Effective  Time,  SLH shall  increase the
number of authorized shares of SLH Junior Preferred Stock to 250,000.

         (e) No Acquisitions.  Other than acquisitions listed on Schedule 4.2(e)
of the SLH Letter, SLH shall not and it shall not permit any of its Subsidiaries
to,  acquire  or agree to  acquire  by  merging  or  consolidating  with,  or by
purchasing a  substantial  equity  interest in or a  substantial  portion of the
assets of, or by any other manner, any business or any corporation, partnership,
association or other business organization or division thereof.

         (f) No  Dispositions.  Other than: (i)  dispositions  of real estate to
unaffiliated parties or dispositions of interests in entities, substantially all
of the  assets of which  consist  of real  estate,  to  unaffiliated  parties or
proposed  dispositions  listed on Schedule 4.2(f) of the SLH Letter; (ii) as may
be  necessary or required by law to  consummate  the  transactions  contemplated
hereby;   or  (iii)   dispositions  of  other  assets  that  are  not  material,
individually or in the aggregate,  to SLH and its Subsidiaries taken as a whole,
SLH shall not and it shall not permit any of its  Subsidiaries  to sell,  lease,
encumber or otherwise dispose of, or agree to sell, lease (whether such lease is
an operating

                                       42

or  capital  lease),  encumber  or  otherwise  dispose  of,  any of its  assets.
Notwithstanding  the  foregoing,  none of SLH nor its  Subsidiaries  shall sell,
lease,  encumber or otherwise dispose of, or agree to dispose of, (A) any of its
assets to any Related Person other than in the ordinary course of business on an
arms length basis or (B) any shares of Syntroleum Common Stock.

         (g) No Dissolution,  Etc. Except as otherwise permitted or contemplated
by this Agreement,  SLH shall not authorize,  recommend,  propose or announce an
intention to adopt a plan of complete or partial  liquidation  or dissolution of
SLH or any of its Significant Subsidiaries.

         (h) Certain Employee Matters. Except as set forth on Schedule 4.2(h) of
the SLH  Letter,  SLH shall not and it shall not permit any of its  Subsidiaries
to:  (i)  grant  any  increases  in the  compensation  of any of its  directors,
officers or employees,  except  increases in the ordinary course of business and
in  accordance  with  past  practice;  (ii)  pay or  agree  to pay any  pension,
retirement  allowance or other employee  benefit not required or contemplated by
any of the existing  SLH Benefit  Programs or SLH Plans as in effect on the date
hereof to any such director, officer or employee, whether past or present; (iii)
enter  into  any  new,  or  amend  any  existing,  employment  or  severance  or
termination   agreement  with  any  such  director,   officer  or  key  employee
(including, without limitation, with respect to the terminations contemplated by
Section 5.16 hereof); or (iv) become obligated under any new SLH Benefit Program
or SLH Plan, which was not in existence or approved by the Board of Directors of
SLH prior to or on the date  hereof,  or amend any such plan or  arrangement  in
existence  on the  date  hereof  if such  amendment  would  have the  effect  of
materially enhancing any benefits thereunder.

         (i) Indebtedness;  Leases; Capital Expenditures. Except as set forth on
Schedule  4.2(i) of the SLH Letter,  SLH shall not,  nor shall SLH permit any of
its  Subsidiaries  to, (i) incur any indebtedness for borrowed money (except for
working  capital under SLH's existing  credit  facilities,  and  refinancings of
existing debt that permit  prepayment of such debt without penalty) or guarantee
any such indebtedness or issue or sell any debt securities or warrants or rights
to  acquire  any debt  securities  of such party or any of its  Subsidiaries  or
guarantee any debt  securities of others,  (ii) except in the ordinary course of
business,  enter into any lease  (whether  such lease is an operating or capital
lease) or create any mortgages,  liens, security interests or other encumbrances
on the  property  of SLH or any of  its  Subsidiaries  in  connection  with  any
indebtedness  thereof,  except for those securing purchase money indebtedness or
(iii) commit to aggregate capital expenditures in excess of $100,000 outside the
capital  budget,  as  approved  by SLH prior to the date hereof and set forth on
Schedule 4.2(i) of the SLH Letter.

         (j) No Solicitation.  From and after the date hereof, SLH will not, and
will not authorize or permit any of its officers,  directors,  employees, agents
and other  representatives  or those of any of its  Subsidiaries  (collectively,
"SLH  Representatives")  to,  directly or  indirectly,  solicit or initiate  any
prospective  buyer  or the  making  of any  proposal  that  constitutes,  or may
reasonably  be  expected  to lead to, a SLH  Acquisition  Proposal  (as  defined
herein) from any person;  provided,  however,  that,  notwithstanding  any other
provision of this  Agreement,  (i) SLH may engage in discussions or negotiations
with a third party who  (without any  solicitation  or  initiation,  directly or
indirectly, by

                                       43

or with SLH or any SLH  Representatives  after the date of this Agreement) seeks
to initiate such  discussions or  negotiations  and may furnish such third party
information  concerning SLH and its business,  properties and assets, (ii) SLH's
Board of  Directors  may take and  disclose  to SLH's  stockholders  a  position
contemplated  by Rule  14e-2(a)  promulgated  under the  Exchange  Act and (iii)
following receipt of a SLH Acquisition  Proposal that is financially superior to
the Merger and reasonably  capable of being financed (as determined in each case
in good  faith by  SLH's  Board  of  Directors  after  consultation  with  SLH's
financial advisors),  the Board of Directors of SLH may withdraw,  modify or not
make its  recommendation  referred to in Section 5.5 or terminate this Agreement
in accordance with Section 7.1(b), but in each case referred to in the foregoing
clauses (i) through  (iii) only to the extent that the Board of Directors of SLH
shall  conclude  in good faith that such  action is  necessary  in order for the
Board  of  Directors  of SLH to act in a  manner  that is  consistent  with  its
fiduciary  obligations  under  applicable law. SLH shall  immediately  cease and
cause to be terminated  any existing  solicitation,  initiation,  encouragement,
activity, discussion or negotiation with any parties conducted heretofore by SLH
or any SLH representatives with respect to any SLH Acquisition Proposal existing
on the date hereof. SLH will promptly notify Syntroleum of any such requests for
such information or the receipt of any SLH Acquisition  Proposal,  including the
identity of the person or group engaging in such  discussions  or  negotiations,
requesting such information or making such SLH Acquisition Proposal, and (unless
the Board of Directors of SLH concludes such disclosure is inconsistent with its
fiduciary obligations under applicable law) the material terms and conditions of
any SLH  Acquisition  Proposal.  As used in  this  Agreement,  "SLH  Acquisition
Proposal"  shall mean any  proposal or offer,  other than a proposal or offer by
Syntroleum or any of its  affiliates,  for a tender or exchange offer, a merger,
consolidation or other business  combination  involving SLH or any Subsidiary of
SLH or any proposal to acquire in any manner a substantial  equity  interest in,
or substantially all of the assets of, SLH or any of its Subsidiaries.


                                    ARTICLE V

                              ADDITIONAL AGREEMENTS

         5.1  Preparation  of S-4 and the Proxy  Statement.  SLH shall  promptly
prepare  and file with the SEC the  Proxy  Statement  and the S-4,  in which the
Proxy Statement will be included as a prospectus. SLH shall use its commercially
reasonable  efforts to have the S-4 declared  effective under the Securities Act
as promptly as  practicable  after such filing.  SLH shall use its  commercially
reasonable  efforts to cause the Proxy Statement to be mailed to stockholders of
SLH at the earliest  practicable  date.  Syntroleum  shall use its  commercially
reasonable  efforts to cause the Proxy Statement to be mailed to stockholders of
Syntroleum  at the earliest  practicable  date.  SLH shall use its  commercially
reasonable  efforts to obtain all necessary state  securities laws or "blue sky"
permits,  approvals and  registrations  in  connection  with the issuance of SLH
Common Stock in the Merger and upon the exercise of Syntroleum Stock Options (as
defined herein).  Syntroleum shall furnish all information concerning Syntroleum
and the holders of  Syntroleum  Common  Stock,  including  financial  statements
required  by Form S-4 and the  proxy  rules  under  the  Exchange  Act as may be
reasonably  requested in connection  with obtaining such permits,  approvals and
registrations.

                                       44

         5.2  Letter  of  Syntroleum's  Accountants.  Syntroleum  shall  use its
commercially  reasonable  efforts  to cause to be  delivered  to SLH a letter of
Arthur Andersen LLP, Syntroleum's  independent public accountants,  dated a date
within two business days before the date on which the S-4 shall become effective
and  addressed  to SLH and the  individuals  listed  on  Exhibit  B, in form and
substance  reasonably  satisfactory  to SLH and customary in scope and substance
for letters  delivered by  independent  public  accountants  in connection  with
registration statements similar to the S-4.

         5.3  Letter  of  SLH's  Accountants.  SLH  shall  use its  commercially
reasonable efforts to cause a letter of KPMG Peat Marwick LLP, SLH's independent
public  accountants,  dated a date within two  business  days before the date on
which the S-4 shall become  effective and  addressed to SLH and the  individuals
listed on Exhibit B, in form and substance  reasonably  satisfactory  to SLH and
Syntroleum  and  customary  in scope and  substance  for  letters  delivered  by
independent  public  accountants  in  connection  with  registration  statements
similar to the S-4 to be delivered and addressed to such persons and entities as
is customary for similar letters.

         5.4 Access to Information.  Upon reasonable notice,  Syntroleum and SLH
shall each (and shall cause each of their respective  Subsidiaries to) afford to
the officers, employees,  accountants,  counsel and other representatives of the
other,  access,  during  normal  business  hours  during the period prior to the
Effective Time, to all its properties, books, contracts, commitments and records
and, during such period,  each of Syntroleum and SLH shall (and shall cause each
of their respective Subsidiaries to) furnish promptly to the other (a) a copy of
each quarterly,  annual or current report on Form 10-Q,  10-K or 8-K,  schedule,
registration  statement and other  document  filed or received by it during such
period pursuant to SEC requirements and (b) all other information concerning its
business,  properties and personnel as such other party may reasonably  request,
excluding, however, information covered by confidentiality agreements with third
parties.  Each of Syntroleum and SLH agrees that it will not, and will cause its
respective representatives not to, use any information obtained pursuant to this
Section 5.4 for any purpose  unrelated to the  consummation of the  transactions
contemplated by this Agreement. The Confidentiality Agreements dated as of March
13, 1998 between SLH and Syntroleum  (the  "Confidentiality  Agreements")  shall
apply with respect to  information  furnished  thereunder  or hereunder  and any
other activities contemplated thereby.

         5.5 Stockholders Meetings. Syntroleum and SLH shall each call a meeting
of its stockholders (respectively,  the "Syntroleum Stockholder Meeting" and the
"SLH Stockholder Meeting" and, collectively,  the "Stockholder  Meetings") to be
held as promptly as practicable  after the date hereof for the purpose of voting
upon this  Agreement  and the Merger.  Subject  only to the proviso of the first
sentence of Section  4.1(j),  Syntroleum  will,  through its Board of Directors,
recommend  to its  stockholders  approval of such  matters and not rescind  such
recommendation  and  shall use its  commercially  reasonable  efforts  to obtain
approval  and  adoption of this  Agreement  and the Merger by its  stockholders.
Subject only to the proviso of the first sentence of Section  4.2(j),  SLH will,
through its Board of Directors,  recommend to its stockholders  approval of such
matters  and not  rescind  such  recommendation  and shall use its  commercially
reasonable  efforts to obtain  approval and adoption of this  Agreement  and the
Merger by its stockholders. Syntroleum and SLH

                                       45

shall  coordinate  and cooperate with respect to the timing of such meetings and
shall use their  commercially  reasonable  efforts to hold such  meetings on the
same day.

         5.6  Legal  Conditions  to  Merger.  Syntroleum  and SLH will  take all
reasonable actions necessary to comply promptly with all legal requirements that
may be  imposed on such party  with  respect to the Merger  (including,  without
limitation,  furnishing  all  information  in  connection  with  approvals of or
filings  with any  Governmental  Entity) and will  promptly  cooperate  with and
furnish  information  to each  other in  connection  with any such  requirements
imposed upon any of them or any of their  Subsidiaries  in  connection  with the
Merger.  Syntroleum and SLH will, and will cause its  Subsidiaries  to, take all
actions  necessary to obtain (and will  cooperate  with each other in obtaining)
any consent, acquiescence, authorization, order or approval of, or any exemption
or nonopposition  by, any Governmental  Entity,  court or other person or entity
required to be obtained or made by Syntroleum,  SLH or any of their Subsidiaries
in connection with the Merger or the taking of any action  contemplated  thereby
or by this Agreement.

         5.7 Agreements of Others. Prior to the Effective Time, Syntroleum shall
cause to be prepared and delivered to SLH a list identifying all persons who, at
the time of Syntroleum  Stockholder  Meeting may be deemed to be "affiliates" of
Syntroleum as that term is used in paragraphs  (c) and (d) of Rule 145 under the
Securities  Act  (the  "Affiliates").  Syntroleum  shall  use  its  commercially
reasonable  efforts to cause each person who is  identified  as an  Affiliate in
such  list to  deliver  to SLH,  at or prior to the  Effective  Time,  a written
agreement,  in a form mutually agreeable to Syntroleum and SLH whereby each such
person acknowledges that such person is subject to the provisions of Rule 145(d)
promulgated under the Securities Act.

         5.8 Listing. SLH shall use its commercially reasonable efforts to cause
the shares of SLH  Common  Stock to be issued in the  Merger,  the shares of SLH
Common Stock  issuable upon  exercise of  Syntroleum  Stock Options and issuable
under  Syntroleum  Stock  Option  Plans to be approved for trading on the Nasdaq
Stock Market, subject to official notice of issuance, prior to the Closing Date.

         5.9 Board of  Directors  and  Officers.  SLH shall  take all  necessary
action so that as of the Effective  Time the directors and officers of SLH shall
only be those  individuals  identified as directors  and officers,  on Exhibit B
hereto, except to the extent any such individual is unwilling or unable to serve
in such  capacity.  If prior to the Effective  Time an individual  identified on
Exhibit B hereto as a director  or officer  is  unwilling  or unable to serve in
such capacity, then unless such individual is Mr. P. Anthony Jacobs or Mr. James
R. Seward the  directors of SLH specified on Exhibit B that are willing and able
to serve shall fill any vacancies promptly after the Effective Time. If prior to
the Effective  Time or thereafter at anytime prior to the 2001 Annual Meeting of
Stockholders  of SLH  either Mr. P.  Anthony  Jacobs or Mr.  James R.  Seward is
unwilling or unable to serve as a director of SLH, then either Mr. Jacobs or Mr.
Seward  (whichever  continues  to be willing  and able to serve as a director of
SLH)  shall  be  entitled  to  recommend  to the  Board of  Directors  of SLH an
individual to fill the vacancy and SLH shall support such recommendation.

                                       46

         5.10 Stock Options;  Reservation and Registration of Shares. (a) At the
Effective Time, each outstanding option to purchase  Syntroleum Common Stock and
any stock appreciation rights related thereto that have been granted pursuant to
Syntroleum  Stock Option Plans and the Consultant  Option (a  "Syntroleum  Stock
Option"),  whether vested or unvested, shall be assumed by SLH. Each such option
shall be  deemed to  constitute  an option  to  acquire,  on the same  terms and
conditions as were applicable  under such Syntroleum  Stock Option,  a number of
shares of SLH Common  Stock equal to the number of shares of  Syntroleum  Common
Stock  purchasable  pursuant to such Syntroleum  Stock Option  multiplied by the
Exchange Ratio, at a price per share of SLH Common Stock equal to the per- share
exercise price for the shares of Syntroleum Common Stock purchasable pursuant to
such Syntroleum Stock Option divided by the Exchange Ratio;  provided,  however,
that in the case of any  option  to which  Section  421 of the Code  applies  by
reason of its  qualification  under any of  Sections  422-424  of the Code,  the
option price, the number of shares  purchasable  pursuant to such option and the
terms and  conditions of exercise of such option shall be determined in order to
comply with Section 424(a) of the Code; and provided further, that the number of
shares  of SLH  Common  Stock  that  may be  purchased  upon  exercise  of  such
Syntroleum  Stock  Option  shall not  include  any  fractional  share and,  upon
exercise of such Syntroleum  Stock Option,  a cash payment shall be made for any
fractional  share based upon the closing price of a share of SLH Common Stock on
the Nasdaq Stock Market or, if then traded on an exchange, such exchange, on the
last  trading  day of the  calendar  month  immediately  preceding  the  date of
exercise.

         (c) SLH shall  take all  corporate  action  necessary  to  reserve  for
issuance a sufficient  number of shares of SLH Common  Stock for  delivery  upon
exercise of Syntroleum Stock Options. As soon as practicable after the Effective
Time, SLH shall file with the SEC a  registration  statement on Form S-8 (or any
successor  form) or another  appropriate  form with respect to the shares of SLH
Common Stock  subject to  Syntroleum  Stock Options and shall use its efforts to
maintain  the  effectiveness  of such  registration  statement  or  registration
statements  (and maintain the current status of the  prospectus or  prospectuses
contained therein) for so long as Syntroleum Stock Options remain outstanding.

         5.11 Indemnification;  Directors' and Officers' Insurance. (a) From and
after the Effective Time, the Surviving Corporation shall indemnify,  defend and
hold  harmless each person who is now, or has been at any time prior to the date
hereof or who becomes prior to the Effective Time, an officer or director of the
SLH or  Syntroleum  or any of their  Subsidiaries  or an  employee of the SLH or
Syntroleum or any of their Subsidiaries who acts as a fiduciary under any of the
SLH Benefit Programs,  the SLH Plans,  Syntroleum Benefit Programs or Syntroleum
Plans (the "Indemnified  Parties") against all losses, claims,  damages,  costs,
expenses (including  attorneys' fees),  liabilities or judgments or amounts that
are paid in  settlement  with the  approval  of the  indemnifying  party  (which
approval  shall  not be  unreasonably  withheld)  of or in  connection  with any
threatened or actual claim, action,  suit,  proceeding or investigation based in
whole or in part on or  arising  in whole or in part out of the fact  that  such
person is or was a director, officer, or such employee of the SLH

                                       47

or  Syntroleum  or any of their  Subsidiaries  whether  pertaining to any matter
existing or occurring at or prior to the Effective Time and whether  asserted or
claimed   prior  to,  or  at  or  after,   the  Effective   Time   ("Indemnified
Liabilities"),  including all Indemnified  Liabilities based in whole or in part
on, or arising in whole or in part out of, or  pertaining  to this  Agreement or
the  transactions  contemplated  hereby,  in  each  case to the  fullest  extent
permitted under applicable law (and the Surviving  Corporation will pay expenses
in advance of the final  disposition  of any such action or  proceedings to each
Indemnified Party to the fullest extent permitted by law).  Without limiting the
foregoing,   in  the  event  any  such  claim,  action,   suit,   proceeding  or
investigation is brought against any Indemnified Parties (whether arising before
or after the Effective  Time),  (i) the  Indemnified  Parties may retain counsel
satisfactory  to  them  and  the  Surviving   Corporation,   and  the  Surviving
Corporation  shall pay all fees and expenses of such counsel for the Indemnified
Parties  promptly as statements  therefor are  received;  and (ii) the Surviving
Corporation  will use all  commercially  reasonable  efforts  to  assist  in the
vigorous  defense of any such matter,  provided that the  Surviving  Corporation
shall not be liable for any  settlement  effected  without its written  consent,
which consent,  however,  shall not be  unreasonably  withheld.  Any Indemnified
Party wishing to claim indemnification under this Section 5.11, upon learning of
any such claim,  action,  suit,  proceeding or  investigation,  shall notify the
Surviving  Corporation,  but the failure so to notify  shall not relieve a party
from any  liability  that it may have under  this  Section  5.11,  except to the
extent such failure materially prejudices such party. The Indemnified Parties as
a group may retain only one law firm to represent them with respect to each such
matter unless there is, under applicable  standards of professional  conduct,  a
conflict  on any  significant  issue  between the  positions  of any two or more
Indemnified   Parties.   Syntroleum   and  SLH   agree   that  all   rights   to
indemnification,  including provisions relating to advances of expenses incurred
in defense of any action or suit,  existing in favor of the Indemnified  Parties
(including in the Articles of Incorporation or Bylaws or in the  indemnification
agreements  previously  provided by SLH to  Syntroleum)  with respect to matters
occurring  through  the  Effective  Time,  shall  survive  the  Merger and shall
continue  in full force and effect for a period of six years from the  Effective
Time;  provided,  however,  that all rights to indemnification in respect of any
Indemnified Liabilities asserted or made within such period shall continue until
the disposition of such Indemnified Liabilities.

         (b) After the Effective Time SLH shall cause to be maintained in effect
the current policies of directors' and officers' liability insurance  maintained
by SLH and  Syntroleum  and its  Subsidiaries  or other  policies of  comparable
coverage and amounts with respect to matters  arising  before the Effective Time
covering  Indemnified Parties who are directors or officers of SLH and who cease
to be employed as a director or officer of the SLH within  three years after the
Effective Time, such that if a claim is made against any such Indemnified Person
during the six years  following the Effective  Time with respect to  occurrences
arising prior to the Effective Time, the Indemnified  Person would be covered as
if (a) the  Indemnified  Person  has not ceased to be so  employed  and (b) such
insurance was still in effect.

         5.12 Public  Announcements.  SLH and Syntroleum  will consult with each
other before issuing any press release or otherwise making any public statements
with respect to the transactions  contemplated by this Agreement,  and shall not
issue any such press release or make any such public

                                       48

statement  prior to such  consultation,  except as may be required by applicable
law or by  obligations  pursuant  to any  listing  agreement  with any  national
securities exchange or transaction reporting system.

         5.13 Other Actions.  Except as contemplated by this Agreement,  neither
SLH nor Syntroleum  shall, and shall not permit any of its Subsidiaries to, take
or agree or commit to take any action that is reasonably likely to result in any
of its respective  representations  or warranties  hereunder being untrue in any
material  respect or in any of the conditions to the Merger set forth in Article
VI not being  satisfied.  Upon the terms and subject to the conditions set forth
in this  Agreement,  each of the parties  hereto agrees to use its  commercially
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 Merger and the other transactions
contemplated by this Agreement.

         5.14 Advice of Changes; SEC Filings. SLH and Syntroleum shall confer on
a regular  basis with each other,  report on  operational  matters and  promptly
advise each other orally and in writing of any change or event having, or which,
insofar as can reasonably be foreseen, could have, a SLH Material Adverse Effect
or Syntroleum Material Adverse Effect. Syntroleum and SLH shall promptly provide
each other (or their  respective  counsel)  copies of all  filings  made by such
party  with  the SEC or any  other  state  or  federal  Governmental  Entity  in
connection with this Agreement and the transactions contemplated hereby.

         5.15 Reorganization. It is the intention of SLH and Syntroleum that the
Merger will qualify as a reorganization  described in Section 368(a) of the Code
(and any comparable  provisions of applicable  state or local law).  Neither SLH
nor Syntroleum (nor any of their respective  Subsidiaries)  will take or omit to
take any action (whether before,  on or after the Closing Date) that would cause
the Merger not to be so treated.  The parties  will  characterize  the Merger as
such a reorganization for purposes of all Returns and other filings.

         5.16  Termination of Certain SLH Employees.  Prior to the Closing Date,
SLH shall  terminate the  employment  of all of its  employees  other than those
identified on Schedule 5.16 of the SLH Letter.


                                   ARTICLE VI

                              CONDITIONS PRECEDENT

         6.1  Conditions to Each Party's  Obligation  to Effect the Merger.  The
respective obligation of each party to effect the Merger shall be subject to the
satisfaction prior to the Closing Date of the following conditions:

                                       49

         (a) Stockholder Approval. This Agreement and the Merger shall have been
approved and adopted by the affirmative vote of the holders of a majority of the
outstanding  shares of  Syntroleum  Common  Stock  entitled  to vote  thereon at
Syntroleum  Stockholder  Meeting and shall have been approved and adopted by the
holders of a majority of the outstanding  shares of SLH Common Stock entitled to
vote thereon at the SLH Stockholder Meeting.

         (b)  Listing.  The shares of SLH Common  Stock  issuable to  Syntroleum
stockholders  pursuant  to this  Agreement  and such other  shares of SLH Common
Stock  required to be reserved for issuance in connection  with the Merger shall
have been  authorized  for trading on the Nasdaq  Stock  Market,  upon  official
notice of issuance.

         (c) Other  Approvals.  All  filings  required  to be made  prior to the
Effective Time with,  and all consents,  approvals,  permits and  authorizations
required to be obtained prior to the Effective Time from any Governmental Entity
in  connection  with  the  execution  and  delivery  of this  Agreement  and the
consummation of the transactions contemplated hereby by Syntroleum and SLH shall
have been made or  obtained  (as the case may be),  except  where the failure to
obtain  such  consents,  approvals,  permits,  and  authorizations  would not be
reasonably  likely to  result  in a  material  adverse  effect to the  business,
operations,  assets,  condition (financial or otherwise) or results of operation
of SLH and its  Subsidiaries  taken as a whole  (assuming  the  Merger has taken
place) or to materially adversely affect the consummation of the Merger.

         (d) S-4. The S-4 shall have become  effective  under the Securities Act
and shall not be the  subject  of any stop order or  proceedings  seeking a stop
order.

         (e) No  Injunctions  or  Restraints.  No temporary  restraining  order,
preliminary  or  permanent  injunction  or other  order  issued  by any court of
competent jurisdiction or other legal restraint or prohibition (an "Injunction")
preventing the consummation of the Merger shall be in effect.

         (f)  Dissenters.  The  aggregate  number of shares  held by  holders of
Syntroleum  Common Stock who have made demands for appraisal in accordance  with
the Oklahoma Act shall not exceed 2.5% of the shares of Syntroleum  Common Stock
outstanding and entitled to vote at Syntroleum Stockholders Meeting.

         (g)  Accounting  Treatment.  The  historical  or  pro  forma  financial
statements  included  in the S-4 that is declared  effective  by the SEC and the
definitive  preliminary  proxy materials that are distributed to stockholders of
the parties  shall not reflect  fundamental  and material  variances  from those
initially filed (which shall not be materially  inconsistent with the accounting
treatment  currently  contemplated by the parties) that are not  satisfactory to
the Board of Directors of both SLH and Syntroleum.

         (h)      Tax Opinion.   Syntroleum  and  SLH  shall  have  received  an
opinion, reasonably satisfactory to both Syntroleum and SLH, dated on  or  about
the date that is two days prior to the date

                                       50

the Proxy  Statement  is first  mailed to  stockholders  of the SLH,  of Baker &
Botts,  L.L.P.,  counsel to  Syntroleum,  to the effect  that,  if the Merger is
consummated in accordance with the terms of this Agreement, the Merger will be a
reorganization  within  the  meaning  of  Section  368(a) of the  Code,  SLH and
Syntroleum  will each be a party to that  reorganization  within the  meaning of
Section  368(b) of the Code and no gain or loss will be  recognized  for  United
States  federal  income tax  purposes by SLH,  Syntroleum  or a  stockholder  of
Syntroleum  as a result  of the  Merger  or upon the  conversion  of  shares  of
Syntroleum  Common  Stock into shares of SLH Common Stock except with respect to
cash,  if any,  which is  received  in lieu of  fractional  shares of SLH Common
Stock. In rendering such opinion,  such counsel may rely upon representations of
Syntroleum and SLH substantially in the form of Exhibit C attached hereto.

         6.2 Conditions of Obligations of SLH. The  obligations of SLH to effect
the Merger are subject to the satisfaction of the following  conditions,  any or
all of which may be waived in whole or in part by SLH.

         (a)  Representations  and Warranties.  Each of the  representations and
warranties of Syntroleum set forth in this  Agreement  shall be true and correct
as of the date of this Agreement and (except to the extent such  representations
and  warranties  speak as of an earlier  date) as of the Closing  Date as though
made on and as of the Closing  Date  except for such  failures to be so true and
correct  (without  giving  effect  to  the  individual   materiality  thresholds
otherwise  contained in Section 3.1 hereof) which would not,  individually or in
the  aggregate,  reasonably  be expected to have a Syntroleum  Material  Adverse
Effect or which were provided by, or in accordance with, this Agreement.

         (b)  Performance of Obligations  of Syntroleum.  Syntroleum  shall have
performed in all material  respects all obligations  required to be performed by
it under this Agreement at or prior to the Closing Date.

         (c)      No Vesting of Syntroleum Stock Options.     Syntroleum   Stock
Options shall not vest as a result of the Merger  and  will  maintain  the  same
vesting period as if the Merger had not occurred.

         (d)      Fairness Opinion.  The opinion  described  in  Section  3.2(q)
shall not have been withdrawn.

         (e)  Officers'  Certificate.  SLH shall have received (i) a certificate
dated as of the  Closing  Date and signed on behalf of  Syntroleum  by its chief
executive officer or president and by its chief financial officer, to the effect
that the conditions set forth in Section 6.1 hereof as they relate to Syntroleum
and in Section 6.2(a) and (b) have been  satisfied and (ii) certified  copies of
resolutions  duly adopted by  Syntroleum's  Board of Directors and  stockholders
evidencing  the  taking of all  corporate  action  necessary  to  authorize  the
execution,  delivery and  performance of this Agreement and the  consummation of
the transactions  contemplated  hereby, all in such reasonable detail as SLH and
its counsel shall request.

                                       51

         (f) Letters from  Affiliates.  SLH shall have received from each person
named in the letter  referred to in Section 5.7 an executed copy of an agreement
as provided in Section 5.7.

         (g)  Opinion of  Counsel to  Syntroleum.  Syntroleum  shall  deliver an
opinion  from  counsel  to   Syntroleum,   in  form  and  substance   reasonably
satisfactory to SLH, covering the matters set forth on Exhibit D hereto.

         6.3  Conditions  of  Obligations  of  Syntroleum.   The  obligation  of
Syntroleum to effect the Merger is subject to the  satisfaction of the following
conditions, any or all of which may be waived in whole or in part by Syntroleum:

         (a)  Representations  and Warranties.  Each of the  representations and
warranties  of SLH set forth in this  Agreement  shall be true and correct as of
the date of this  Agreement and (except to the extent such  representations  and
warranties speak as of an earlier date) as of the Closing Date as though made on
and as of the Closing  Date  except for such  failures to be so true and correct
which (without giving effect to the individual  materiality thresholds otherwise
contained in Section 3.2 hereof) would not,  individually  or in the  aggregate,
reasonably  be  expected  to have a SLH  Material  Adverse  Effect or which were
provided by or in accordance with this Agreement.

         (b)  Performance of Obligations of SLH. SLH shall have performed in all
material  respects all  obligations  required to be performed by them under this
Agreement at or prior to the Closing Date.

         (c)      Fairness Opinion.  The opinion  described  in  Section  3.1(q)
shall not have been withdrawn.

         (d)  Officers'  Certificate.  Syntroleum  shall  have  received  (i)  a
certificate  dated as of the  Closing  Date and  signed  on behalf of SLH by its
chief executive officer and by its chief financial  officer,  to the effect that
the  conditions  set forth in Section  6.1  hereof as they  relate to SLH and in
Section  6.3(a)  and (b) have  been  satisfied  and  (ii)  certified  copies  of
resolutions duly adopted by SLH's Board of Directors and stockholders evidencing
the  taking of all  corporate  action  necessary  to  authorize  the  execution,
delivery  and  performance  of  this  Agreement  and  the  consummation  of  the
transactions  contemplated  hereby,  all in such reasonable detail as Syntroleum
and its counsel shall request.

         (e) Board of Directors  and Officers at the  Effective  Time. As of the
closing  date,  SLH shall have  delivered to Syntroleum  irrevocable  letters of
resignation effective as of the Effective Time from all of the current directors
and officers of SLH other than individuals  identified as directors on Exhibit B
hereto.  The delivery of such resignations by officers of SLH shall be deemed to
be a termination without cause under their existing employment agreements.

                                       52

         (f)  Opinion  of  Counsel to SLH.  SLH shall  deliver  an opinion  from
counsel to SLH in form and  substance  reasonably  satisfactory  to  Syntroleum,
covering the matters set forth on Exhibit E hereto.

         (g) Consents of Optionees.  All holders of SLH Stock Options shall have
delivered  written  consents  to the  adjustments  set forth in  Section  2.1(b)
hereof.


                                   ARTICLE VII

                            TERMINATION AND AMENDMENT

         7.1 Termination. This Agreement may be terminated and the Merger may be
abandoned  at any time  prior to the  Effective  Time,  whether  before or after
approval  of  the  matters  presented  in  connection  with  the  Merger  by the
stockholders of Syntroleum or SLH:

         (a)      by mutual written consent of Syntroleum and SLH, or by  mutual
action of their respective Boards of Directors;

         (b) by either  Syntroleum  or SLH if (i) the Merger shall not have been
consummated  by September 30, 1998  (provided  that the right to terminate  this
Agreement under this clause (i) shall not be available to any party whose breach
of any  representation  or  warranty  or  failure  to fulfill  any  covenant  or
agreement  under this Agreement has been the cause of or resulted in the failure
of the  Merger to occur on or before  such  date);  (ii) any court of  competent
jurisdiction, or some other governmental body or regulatory authority shall have
issued an  order,  decree  or  ruling  or taken  any  other  action  permanently
restraining,  enjoining  or  otherwise  prohibiting  the Merger and such  order,
decree, ruling or other action shall have become final and nonappealable;  (iii)
the  stockholders  of the SLH shall not approve this Agreement and the Merger at
the SLH Stockholder Meeting or at any adjournment thereof; (iv) the stockholders
of  Syntroleum  shall not approve this  Agreement  and the Merger at  Syntroleum
Stockholders  Meeting or at any adjournment  thereof; (v) in the exercise of its
good faith judgment as to its fiduciary  duties to its  stockholders  imposed by
law, as advised by outside  counsel,  the Board of Directors  of SLH  determines
that such termination is required by reason of a SLH Acquisition Proposal having
been made,  provided that SLH may not terminate this Agreement  pursuant to this
clause (v) unless  five  business  days shall have  elapsed  after  delivery  to
Syntroleum  of a written  notification  of SLH's  intention  to  terminate  this
Agreement  and  during  such  five  business-day  period  SLH shall  have  fully
cooperated with Syntroleum;  including, without limitation, informing Syntroleum
of the terms and conditions of such SLH Acquisition Proposal and the identity of
the person or group  making such SLH  Acquisition  Proposal,  with the intent of
enabling  Syntroleum to agree to a  modification  of the terms and conditions of
this Agreement so that the transactions  contemplated hereby may be effected; or
(vi) in the exercise of its good faith  judgment as to its  fiduciary  duties to
its  stockholders  imposed by law, as advised by outside  counsel,  the Board of
Directors of Syntroleum  determines that such  termination is required by reason
of a Syntroleum  Acquisition Proposal having been made, provided that Syntroleum
may not terminate

                                       53

this Agreement pursuant to this clause (vi) unless five business days shall have
elapsed  after  delivery  to  SLH  of a  written  notification  of  Syntroleum's
intention to terminate this Agreement and during such five  business-day  period
Syntroleum shall have fully cooperated with SLH; including,  without limitation,
informing  SLH of the  terms  and  conditions  of  such  Syntroleum  Acquisition
Proposal  and the  identity  of the  person  or  group  making  such  Syntroleum
Acquisition Proposal, with the intent of enabling SLH to agree to a modification
of the  terms  and  conditions  of  this  Agreement  so  that  the  transactions
contemplated hereby may be effected;

         (c) by SLH if  (i)  Syntroleum  shall  have  failed  to  comply  in any
material  respect  with any of the  covenants  or  agreements  contained in this
Agreement to be complied  with or performed  by  Syntroleum  at or prior to such
date of  termination  (provided  such  breach has not been cured  within 30 days
following receipt by Syntroleum of written notice from SLH of such breach and is
existing at the time of termination of this Agreement);  (ii) any representation
or warranty of Syntroleum  contained in this Agreement  shall not be true in all
material  respects when made  (provided such breach has not been cured within 30
days  following  receipt by Syntroleum of written notice from SLH of such breach
and is existing at the time of  termination  of this  Agreement) or on and as of
the  Effective  Time as if made on and as of the  Effective  Time (except to the
extent it relates to a particular date),  except for such failures to be so true
and correct  (without  giving effect to the  individual  materiality  thresholds
otherwise  contained in Section 3.1 hereof) which would not  individually  or in
the  aggregate,  reasonably  be expected to have a Syntroleum  Material  Adverse
Effect or which were provided by, or in accordance with, this Agreement or (iii)
the  Board of  Directors  of  Syntroleum  withdraws,  modifies  or  changes  its
recommendation  of this  Agreement  or the Merger in a manner  adverse to SLH or
shall have resolved to do any of the foregoing; or

         (d) by  Syntroleum  if (i) SLH  shall  have  failed  to  comply  in any
material  respect  with any of the  covenants  or  agreements  contained in this
Agreement  to be complied  with or  performed  by it at or prior to such date of
termination  (provided  such breach has not been cured within 30 days  following
receipt by SLH of written notice from  Syntroleum of such breach and is existing
at the  time of  termination  of this  Agreement);  (ii) any  representation  or
warranty of SLH  contained in this  Agreement  shall not be true in all material
respects  when made  (provided  such  breach has not been  cured  within 30 days
following receipt by SLH of written notice from Syntroleum of such breach and is
existing  at the  time of  termination  of this  Agreement)  or on and as of the
Effective  Time as if made on and as of the Effective Time (except to the extent
it relates to a  particular  date),  except for such  failures to be so true and
correct  (without  giving  effect  to  the  individual   materiality  thresholds
otherwise  contained in Section 3.2 hereof) which would not  individually  or in
the aggregate,  reasonably be expected to have a SLH Material  Adverse Effect or
which were provided by, or in accordance with, this Agreement or (iii) the Board
of Directors of SLH withdraws,  modifies or changes its  recommendation  of this
Agreement or the Merger in a manner adverse to Syntroleum or shall have resolved
to do any of the foregoing.

         7.2  Effect of  Termination.  (a) In the event of  termination  of this
Agreement by either Syntroleum or SLH as provided in Section 7.1, this Agreement
shall forthwith become void and there shall be no liability or obligation on the
part of SLH or Syntroleum except (i) with respect to

                                       54

this Section 7.2, the second and third sentences of Section 5.4 and Section 8.1,
and (ii) and such  termination  shall  not  relieve  any  party  hereto  for any
intentional  breach  prior to such  termination  by a party hereto of any of its
representations or warranties or of any of its covenants or agreements set forth
in this Agreement.

         (b) If this  Agreement  is  terminated  by SLH  pursuant to Section 7.1
(c)(i) or (ii),  and if SLH is not in material  breach of this  Agreement at the
time of such termination, then Syntroleum shall pay the reasonable out-of-pocket
expenses  incurred by SLH in connection  with preparing  for,  entering into and
carrying  out  this  Agreement  and  the   consummation   of  the   transactions
contemplated  hereby. If this Agreement is terminated by Syntroleum  pursuant to
Section  7.1(d)(i) or (ii) and if Syntroleum  is not in material  breach of this
Agreement  at the time of such  termination,  then SLH shall pay the  reasonable
out-of-pocket  expenses incurred by Syntroleum in connection with preparing for,
entering  into and  carrying  out this  Agreement  and the  consummation  of the
transactions contemplated hereby.

         7.3 Amendment.  This Agreement may be amended by the parties hereto, by
action taken or authorized by their respective Boards of Directors,  at any time
before or after approval of the matters  presented in connection with the Merger
by the  stockholders  of  Syntroleum or SLH, but,  after any such  approval,  no
amendment  shall  be  made  which  by law  requires  further  approval  by  such
stockholders  without such further  approval.  This Agreement may not be amended
except by an  instrument  in  writing  signed  on behalf of each of the  parties
hereto.

         7.4  Extension;  Waiver.  At any time prior to the Effective  Time, the
parties  hereto,  by action taken or  authorized by their  respective  Boards of
Directors,  may,  to the  extent  legally  allowed:  (i) extend the time for the
performance of any of the obligations or other acts of the other parties hereto;
(ii) waive any  inaccuracies  in the  representations  and warranties  contained
herein or in any document  delivered pursuant hereto; and (iii) waive compliance
with any of the agreements or conditions  contained herein. Any agreement on the
part of a party  hereto to any such  extension  or waiver shall be valid only if
set forth in a written instrument signed on behalf of such party.


                                  ARTICLE VIII

                               GENERAL PROVISIONS

         8.1 Payment of Expenses.  Except as provided in Section 7.2, each party
hereto shall pay its own expenses  incident to preparing for,  entering into and
carrying  out  this  Agreement  and  the   consummation   of  the   transactions
contemplated hereby, whether or not the Merger shall be consummated.

         8.2      Nonsurvival of Representations, Warranties and Agreements.  
None of the representations, warranties and agreements in this Agreement  or  in
any instrument delivered pursuant to this Agreement shall survive the  Effective
Time and any liability for breach or violation

                                       55

thereof shall terminate  absolutely and be of no further force and effect at and
as of the Effective  Time,  except for the  agreements  contained in Article II,
Sections 5.10 through 5.12 and Article VIII, the agreements  delivered  pursuant
to Section 5.7 and the  representations,  covenants and agreements  contained in
Sections 3.1(u),  3.2(u) and 5.15. The Confidentiality  Agreements shall survive
the  execution  and  delivery  of  this  Agreement,  and the  provisions  of the
Confidentiality Agreements shall apply to all information and material delivered
hereunder.

         8.3  Notices.  Any  notice  or  communication   required  or  permitted
hereunder shall be in writing and either  delivered  personally,  telegraphed or
telecopied or sent by certified or registered mail,  postage prepaid,  and shall
be  deemed  to be  given,  dated  and  received  when so  delivered  personally,
telegraphed  or telecopied  or, if mailed,  five business days after the date of
mailing to the following address or telecopy number, or to such other address or
addresses as such person may subsequently designate by notice given hereunder:

                  (a) if to SLH:

                  James R. Seward
                  SLH Corporation
                  5000 West 95th Street
                  Suite 260, P.O. Box 7568
                  Shawnee Mission, Kansas 66207
                  Phone:  (913) 652-1000
                  Fax:    (913) 652-1025

                  with a copy to:

                  Lathrop & Gage, L.C.
                  2345 Grand Blvd., Suite 250
                  Kansas City, Missouri 64108
                  Attention:  John H. Calvert
                  Phone:  (816) 460-5807
                  Fax:    (816) 292-2001

                  and (b) if to Syntroleum, to:

                  Mark A. Agee
                  Syntroleum Corporation
                  Syntroleum Plaza
                  1350 South Boulder, Suite 1100
                  Tulsa, Oklahoma 74119-3295
                  Phone:  (918) 592-7900
                  Fax:    (918) 592-7979

                                       56

                  with a copy to:

                  Eric Grimshaw
                  Syntroleum Corporation
                  Syntroleum Plaza
                  1350 South Boulder, Suite 1100
                  Tulsa, Oklahoma 74119-3295
                  Phone:  (918) 592-7900
                  Fax:    (918) 592-7979

                  and with a copy to:

                  Baker & Botts, L.L.P.
                  One Shell Plaza
                  910 Louisiana
                  Houston, Texas 77002
                  Attention:  R. Joel Swanson
                  Phone:  (713) 229-1234
                  Fax:    (713) 229-1522

         8.4  Interpretation.  When a  reference  is made in this  Agreement  to
Sections,  such  reference  shall  be to a  Section  of  this  Agreement  unless
otherwise  indicated.  The table of  contents,  glossary  of  defined  terms 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 word "include,"  "includes" or "including" are used in this Agreement,  they
shall be deemed to be followed  by the words  "without  limitation."  The phrase
"made  available" in this Agreement shall mean that the information  referred to
has been made available if requested by the party to whom such information is to
be made available.  Unless the context otherwise  requires,  "or" is disjunctive
but not necessarily exclusive,  and words in the singular include the plural and
in the plural  include the  singular.  Any  representations  and  warranties  of
Syntroleum  that are qualified by the phrase "to the knowledge of Syntroleum" or
phrases  with  similar  wording  shall be  interpreted  to  refer to the  actual
knowledge of the individuals set forth on Schedule 8.4 of Syntroleum Letter. Any
representations  and  warranties of SLH that are qualified by the phrase "to the
knowledge of SLH" or phrases with similar  wording shall be interpreted to refer
to the actual  knowledge of the individuals set forth on Schedule 8.4 of the SLH
Letter.

         8.5  Counterparts.  This  Agreement  may be  executed  in  two or  more
counterparts,  all of which shall be considered  one and the same  agreement and
shall become effective when two or more counterparts have been signed by each of
the parties and delivered to the other  parties,  it being  understood  that all
parties need not sign the same counterpart.

         8.6      Entire Agreement; No Third Party Beneficiaries. This Agreement
(together  with the Confidentiality  Agreements and any other documents  and 
instruments referred to herein) (a)

                                       57

constitutes  the  entire  agreement  and  supersedes  all prior  agreements  and
understandings,  both  written and oral,  among the parties  with respect to the
subject  matter  hereto and (b) except as provided in Sections  3.1(u),  3.2(u),
5.7,  5.11 and 5.15,  is not  intended to confer upon any person  other than the
parties hereto any rights or remedies hereunder.

         8.7 Governing  Law.  Except to the extent that the laws of the State of
Oklahoma are mandatorily applicable to the Merger or the internal affairs of any
of the parties,  this  Agreement  shall be governed and  construed in accordance
with the laws of the State of Kansas, without giving effect to the principles of
conflicts of law thereof.

         8.8  Severability.  Each party agrees  that,  should any court or other
competent  authority  hold any provision of this  Agreement or part hereof to be
null, void or unenforceable,  or order any party to take any action inconsistent
herewith or not to take an action  consistent  herewith or required hereby,  the
validity,   legality  and   enforceability  of  the  remaining   provisions  and
obligations  contained  or set forth  herein shall not in any way be affected or
impaired  thereby,  unless the foregoing  inconsistent  action or the failure to
take an action  constitutes  a material  breach of this  Agreement  or makes the
Agreement  impossible to perform in which case this Agreement shall terminate as
if the parties mutually agreed under Section 7.1(a).

         8.9 Assignment. Neither this Agreement nor any of the rights, interests
or obligations hereunder shall be assigned by any of the parties hereto (whether
by operation of law or otherwise) without the prior written consent of the other
parties. Subject to the preceding sentence, this Agreement will be binding upon,
inure to the benefit of and be enforceable  by the parties and their  respective
successors and assigns.

         IN WITNESS  WHEREOF,  each party has caused this Agreement to be signed
by its respective  officers thereunto duly authorized,  all as of the date first
written above.


                                      SLH CORPORATION


                                      By:     /s/ James R. Seward
                                         Name:    James R. Seward
                                         Title:   President and Chief
                                                  Executive Officer



                                      SYNTROLEUM CORPORATION


                                      By:     /s/ Kenneth L. Agee
                                         Name:    Kenneth L. Agee
                                         Title:   Chairman of the Board and
                                                  Chief Executive Officer

                                       58