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                                                                   Exhibit 10.28

                          STOCK OPTION GRANT AGREEMENT
                          (Non-Qualified Stock Options)

            THIS AGREEMENT, made as of this 8th day of November 1999 between SCG
Holding Corporation (the "Company") and James Thorburn (the "Participant").

            WHEREAS, the Company has adopted and maintains the SCG Holding
Corporation 1999 Founders Stock Option Plan (the "Plan") to promote the
interests of the Company and its Affiliates and stockholders by providing the
Company's key employees and others with an appropriate incentive to encourage
them to continue in the employ of the Company or its affiliates and to improve
the growth and profitability of the Company;

            WHEREAS, the Plan provides for the Grant to Participants in the Plan
of Non-Qualified Stock Options to purchase shares of Common Stock of the
Company.

            NOW, THEREFORE, in consideration of the premises and the mutual
covenants hereinafter set forth, the parties hereto hereby agree as follows:

            1. Grant of Options. Pursuant to, and subject to, the terms and
conditions set forth herein and in the Plan, the Company hereby grants to the
Participant a NON-QUALIFIED STOCK OPTION (the "Option") with respect to 750,000
shares of Common Stock of the Company.

            2. Grant Date. The Grant Date of the Option hereby granted is
September 9, 1999.

            3. Incorporation of Plan. All terms, conditions and restrictions of
the Plan are incorporated herein and made part hereof as if stated herein;
provided that Section 4.6 of the Plan shall not apply to the Participant; and
provided further that Section 4.13(a) shall only apply to the Participant in the
event the Board terminates the Options for all participants in the Plan. If
there is any conflict between the terms and conditions of the Plan and this
Agreement, the terms and conditions of this Agreement, as interpreted by the
Board, shall govern. All capitalized terms used and not defined herein shall
have the meaning given to such terms in the Plan.

            4. Exercise Price. The exercise price of each share underlying the
Option hereby granted is $1.00 per share.

            5. Vesting Date. The Option shall become exercisable as follows:
sixty-three thousand (63,000) shares underlying the Option shall become
exercisable on the Grant Date; an additional sixty-two thousand two hundred
fifty (62,250) shares underlying the Option shall become exercisable six months
following the Grant Date; an additional sixty-two thousand two hundred fifty
(62,250) shares underlying the Option shall become exercisable on the first
anniversary of the Grant Date; and on each six-month anniversary following the
first one-year anniversary of the Grant Date, an additional ninety-three
thousand seven hundred fifty (93,750) shares underlying the Option shall become
exercisable. Notwithstanding the foregoing, in the event of a Change in Control
(as defined in the Plan), any portion of the Option which has not


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expired pursuant to Section 6 below, shall become immediately vested and
exercisable on the date of such Change in Control.

            6. Expiration Date. Subject to the provisions of the Plan, with
respect to the Option or any portion thereof which has not become exercisable,
the Option shall expire on the date the Participant's Employment is terminated
for any reason, and with respect to any Option or any portion thereof which has
become exercisable, the Option shall expire on the earlier of: (i) 90 days after
the Participant's termination of Employment other than for Cause (as defined in
the Participant's employment agreement of the same date hereof), death or
Disability; (ii) one year after termination of the Participant's Employment by
reason of death or Disability; (iii) 30 days after the date the Participant's
Employment is, or is deemed to have been, terminated for Cause; or (iv) the
tenth anniversary of the Grant Date.

            7. Construction of Agreement. Any provision of this Agreement (or
portion thereof) which is deemed invalid, illegal or unenforceable in any
jurisdiction shall, as to that jurisdiction and subject to this section, be
ineffective to the extent of such invalidity, illegality or unenforceability,
without affecting in any way the remaining provisions thereof in such
jurisdiction or rendering that or any other provisions of this Agreement
invalid, illegal, or unenforceable in any other jurisdiction. If any covenant
should be deemed invalid, illegal or unenforceable because its scope is
considered excessive, such covenant shall be modified so that the scope of the
covenant is reduced only to the minimum extent necessary to render the modified
covenant valid, legal and enforceable. No waiver of any provision or violation
of this Agreement by the Company shall be implied by the Company's forbearance
or failure to take action.

            8. Delays or Omissions. No delay or omission to exercise any right,
power or remedy accruing to any party hereto upon any breach or default of any
party under this Agreement, shall impair any such right, power or remedy of such
party nor shall it be construed to be a waiver of any such breach or default, or
an acquiescence therein, or of or in any similar breach or default thereafter
occurring nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of any
party of any breach or default under this Agreement, or any waiver on the part
of any party or any provisions or conditions of this Agreement, shall be in
writing and shall be effective only to the extent specifically set forth in such
writing.

            9. Limitation on Transfer. During the lifetime of the Participant,
the Option shall be exercisable only by the Participant. The Option shall not be
assignable or transferable other than by will or by the laws of descent and
distribution. All shares of Common Stock obtained pursuant to the Option granted
herein shall not be transferred except as provided in the Plan and, where
applicable, the Management Stockholders' Agreement.

            10. Integration. This Agreement, and the other documents referred to
herein or delivered pursuant hereto which form a part hereof contain the entire
understanding of the parties with respect to its subject matter. There are no
restrictions, agreements, promises, representations, warranties, covenants or
undertakings with respect to the subject matter hereof other than those
expressly set forth herein and in the Plan. This Agreement, including without


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limitation the Plan, supersedes all prior agreements and understandings between
the parties with respect to its subject matter.

            11. Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which shall
constitute one and the same instrument.

            12. Governing Law. This Agreement shall be governed by and construed
and enforced in accordance with the laws of the State of Delaware (United States
of America) without regard to the provisions governing conflict of laws.

            13. Participant Acknowledgment. The Participant hereby acknowledges
receipt of a copy of the Plan. The Participant hereby acknowledges that all
decisions, determinations and interpretations of the Board in respect of the
Plan, this Agreement and the Option shall be final and conclusive. The
Participant further acknowledges that, prior to the existence of a Public
Market, no exercise of the Option or any portion thereof shall be effective
unless and until the Participant has executed the Management Stockholders'
Agreement and the Participant hereby agrees to be bound thereby.

                                    * * * * *

            IN WITNESS WHEREOF, the Company has caused this Agreement to be duly
executed by its duly authorized officer and said Participant has hereunto signed
this Agreement on his own behalf, thereby representing that he has carefully
read and understands this Agreement, the Plan and the Management Stockholders'
Agreement as of the day and year first written above.


                                    SCG Holding Corporation


                                    /s/ George H. Cave

                                    By:    George H. Cave
                                    Title: Assistant Secretary & General Counsel


                                    /s/ James Thorburn
                                    --------------------------------------------
                                    James Thorburn


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