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EXHIBIT 10.16(b)




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Amendment to  Second Amended and Restated Production Agreement
 This Amendment to Second Amended and Restated Production Agreement Amendment terling Chemicals,
Inc. Sterling BP Amoco Chemical Company, BP Parties
 Preliminary Statements
 1.
    
    The Parties are parties to that certain Second Amended and Restated Production
Agreement dated effective as of August 1, 1996 (the Original Production
Agreement).2.
    
    The Parties have heretofore amended the Original Production Agreement pursuant to
that certain letter agreement dated September 8, 1998, that certain letter agreement
dated December 28, 1998 and that certain Amendment to Second Amended and Restated
Production Agreement dated effective as of March 1, 2001 (the Original Production
Agreement as so amended, the Existing Production Agreement).3.
    
    The Parties desire to amend the Existing Production Agreement in certain respects
on the terms and subject to the conditions contained herein.
 Now, Therefore
 Profit Sharing Split
  Sharing of Capital Costs
  -2-




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Expansion Projects 2005 Expansion Project
 Amendment of Exhibit H
 No Other Changes
 Binding Effect
 Counterparts
 Severability
 Governing Law This Amendment Shall Be Construed And Enforced In Accordance
With, And The Rights Of The Parties Shall Be Governed By, The Internal Laws Of The State Of Texas,
Without Reference To Principles Of Conflicts Of Law.
 Entire Agreement
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Intending To Be Legally Bound
 BP Amoco Chemical Company
    
    
    
    Sterling Chemicals, Inc.By:
    
    /s/ Paul Watson
    
    
    
    By:
    
    /s/ Paul C. RostekPrinted Name:
    
    Paul Watson
    
    
    
    Printed Name:
    
    Paul C. RostekTitle:
    
    Performance Unit Leader
    
    
    
    Title:
    
    Senior Vice President
 -4-




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Sample Profit Calculations After August 1, 2006
  Example:
    08/01/06  12/31/06  Companys share of Profit more than $***   2007  Companys share of Profit less than $***   2008  Companys share of Profit greater than $*** (Surplus Payment recovery)   2009  Profit less than $***   2010  Companys share of Profit greater than $*** (Surplus Payment recovery)
  Profit Share Calculation
    
    08/06-12/06
    
    2007
    
    2008
    
    2009
    
    2010Profit (excluding Major Capital Items)
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***Companys share of Profit at ***%
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***BPs recovery of Surplus Payments(1)
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***Total due to Company
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***
 Payment of Profit Share
    
    08/06-12/06
    
    2007
    
    2008
    
    2009
    
    2010Total of quarterly advances of
the Companys share of Profit
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***Payment due Company at end of
Contract Year
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***Total cash paid to Company
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***
 Surplus Payment Accumulation
    
    08/06-12/06
    
    2007
    
    2008
    
    2009
    
    2010Balance at end of prior Contract Year
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***Surplus Payment in Contract Year
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***BPs recovery of Surplus Payments
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***Balance at end of Contract Year
    
    ***
    
    ***
    
    ***
    
    ***
    
    ***
 
 (1)
    
    BPs recovery of Surplus Payments for a given Contract Year equals the lesser
of (x) the accumulated Surplus Payment balance at the end of the prior Contract Year and (y)
the Companys share of Profit in excess of the total quarterly advances of the Companys share
of Profit paid during such Contract Year.(2)
    
    The total of quarterly advances of the Companys share of Profit for a given
Contract Year equals $***, provided howeverthat should the Profit for the prior
Contract Year be less than $***, then the total of quarterly advances of the
Companys share of Profit for such Contract Year is equal to the Profit for the prior Contract
Year. H-i