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EXHIBIT 10.23.1

Service Addendum No. 1 to Service Agreement

        Per Article 3 of the Service Agreement (the "Agreement") between The Dow
Chemical Company ("TDCC") and Union Carbide Corporation ("UCC"), with an
Effective Date of 6 February 2001, this Service Addendum specifies services
which TDCC (or its designated Affiliate) is to perform pursuant to the terms and
conditions of the Agreement.

Services:

•Market Research

•Information System Services

•Marketing Communication

•Sales Administration

•General Administration

•Insurance

•Internal Auditing

•Accounting Services

•Human Resources

•Strategic Planning

•Customer Financial Services

•Treasury

•Investor Relations

•Portfolio Investment

•Engineering

•Research and Development

•Legal (including Patent, Trademark and Copyright)

•EH&S

•Tax Administration

•Supply Chain Administration

•Manufacturing Administration

•R&D Administration

•Purchasing

•Export Control/NAFTA compliance/chemical weapons convention support

THE DOW CHEMICAL COMPANY
 
UNION CARBIDE CORPORATION
By:
  

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By:
  

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Name: Arnold A. Allemang   Name: James J. McIlvenny Title: Executive
Vice-President   Title: President Date: February 6, 2001   Date: February 6,
2001

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EXHIBIT 10.23.1