Exhibit 10.1

AMENDMENT TO THE
ARCH SUPPLEMENTARY AND DEFERRAL BENEFIT
PENSION PLAN

WHEREAS, Arch Chemicals, Inc. (the “Company”) sponsors a non-qualified deferred
compensation plan known as the Arch Supplementary and Deferral Benefit Pension
Plan (the “Plan”) for the benefit of certain salaried employees of Arch and
other Employing Companies who may be eligible to participate in the Plan; and

WHEREAS, in Section 7.1 of the Plan, the Company reserved the right to amend the
Plan, in whole or in part, by action of the Compensation Committee of the Board
or any duly authorized officer; and

WHEREAS, the American Jobs Creation Act of 2004 made substantial changes to the
tax laws affecting non-qualified deferred compensation plans effective as of
January 1, 2005, which changes were primarily codified in §409A of the Internal
Revenue Code; and

WHEREAS, the Internal Revenue Service issued preliminary guidance concerning
Code §409A in IRS Notice 2005-1 and in Proposed Treasury Regulations §1.409A-1
through -6 (issued on October 4, 2005), which guidance authorized certain
transition relief concerning plan documentation, deferral elections and
distribution elections; and

WHEREAS, the Company intends to more comprehensively amend and restate the Plan
before December 31, 2006 (the end of the transition relief period), but in the
meantime wishes to amend the Plan to take advantage of certain transition relief
and make other changes to the Plan; and

WHEREAS, the Compensation Committee of the Board authorized the Vice President
of Human Resources for the Company to amend the Plan as necessary or appropriate
to comply with Code §409A and directed that certain other changes be made to the
Plan,

NOW, THEREFORE, the Plan is hereby amended as follows:

1. Except as otherwise provided in this amendment, and notwithstanding any other
provisions in the Plan to the contrary, effective as of January 1, 2005, the
Plan shall be deemed amended to the extent necessary to comply with Code
§409A(a)(2), (3) and (4) with respect to amounts deferred pursuant to the Plan
prior to January 1, 2005 and on and after January 1, 2005, except that benefits
payable to participants who terminated employment and commenced benefit
distributions prior to January 1, 2005 shall continue to be governed by the
terms of the Plan in effect prior to January 1, 2005, and all Plan provisions
shall be interpreted accordingly.

2. Notwithstanding Section 1, above, pursuant to Notice 2005-1, Q&A 19(c), as
extended by the transition relief provided in Section XI, C of the Preamble to
Proposed Regulations, and in accordance with procedures established by the Plan
Administrator, the Plan is hereby amended effective as of January 1, 2005 to the
extent necessary to provide:

 
 

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(a) for new payment elections with respect to amounts deferred prior to the
election, provided the participant makes the election on or before December 31,
2005; and

(b) for new payment elections on or before December 31, 2006 with respect to
both the time and form of payment of amounts subject to such elections, provided
the participant makes any applicable election on or before December 31, 2006 and
provided the election applies only to amounts that would not otherwise be
payable in 2006 and does not cause an amount to be paid in 2006 that would not
otherwise be payable in 2006.

3. Section 2.1 of the Plan is hereby amended, effective as of December 1, 2005,
by adding a new sentence to the end thereof as follows:

Notwithstanding the foregoing, no Employee who is a participant in the Company’s
Senior Executive Pension Plan shall be eligible for benefits under this Plan.

4 Section 4.3 of the Plan is hereby amended, effective as of December 1, 2005,
to the extent it permits benefits to be paid under the Plan in a form other than
a single life annuity, a joint and survivor annuity or a single life annuity
with a term certain feature, except that benefits shall be paid in a single lump
sum if the actuarial present value of the benefit at the benefit commencement
date is less than or equal to Ten Thousand Dollars ($10,000).

5. Section 4.4 and Section 4.5 of the Plan, concerning an employee-grantor trust
option and Accelerated Benefits, are hereby deleted effective as of December 1,
2005.

This amendment shall supersede the provisions of the Plan to the extent that
those provisions are inconsistent with the provisions of this amendment. Except
as amended hereby, and subject to operational compliance with Notice 2005-1 and
applicable Treasury Regulations, the terms of the Plan remain in full force and
effect.

The foregoing amendments shall be effective in accordance with their terms.

IN WITNESS WHEREOF, the undersigned has set his hand as of the third day of
November, 2005.
 

        ARCH CHEMICALS, INC.  
   
   
    By:   /s/Hayes Anderson

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  Its: Vice President, Human Resources  

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Duly Authorized

 
 
 
 

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