Document:

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                                                                   Exhibit 10.12

                              UNR INDUSTRIES, INC.

                        KEY EXECUTIVES' STOCK OPTION PLAN

                      (As Amended and Restated May 6, 1993)

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                                TABLE OF CONTENTS

<TABLE>
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     PARAGRAPH   TITLE                                                                               PAGE
     ---------   -----                                                                               ----
<S>           <C>                                                                                 <C>
        1.       Purpose and Definitions................................................................1
        2.       Scope of the Plan......................................................................2
        3.       Administration.........................................................................3
        4.       Eligibility............................................................................4
        5.       Grants.................................................................................4
        6.       Change of Control......................................................................6
        7.       Exercise...............................................................................8
        8.       Termination of Employment.............................................................11
        9.       No Employment Rights..................................................................11
        10.      Nature of Payments....................................................................12
        11.      Stockholders'Rights...................................................................12
        12.      Adjustments...........................................................................12
        13.      Amendment of the Plan.................................................................12
        14.      Termination of the Plan...............................................................12
        15.      Substituted Options...................................................................12
        16.      Funding...............................................................................13
        17.      Controlling Law.......................................................................13
        18.      Action by the Company.................................................................13

</TABLE>

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             UNR INDUSTRIES, INC. KEY EXECUTIVES' STOCK OPTION PLAN

                  THE PLAN. The Company established the Plan, effective March 6,
1990 (the "Effective Date"). The Company hereby amends and restates the Plan,
effective May 30, 1990. Such establishment of the Plan, as so amended and
restated, is subject to the approval by the holders of a majority of the shares
of common stock and warrants of the Company present or represented and voting at
a meeting duly called and held. Grants may be made hereunder prior to
securityholder approval, provided that any such grants shall be subject to such
securityholders' approval.

                  1. PURPOSE AND DEFINITIONS. The purpose of the Plan is to
advance the interests of the Company and its subsidiaries by encouraging and
facilitating the acquisition of a larger personal financial interest in the
Company by those employees upon whose judgment and interest the Company and its
subsidiaries are largely dependent for the successful conduct of its operations.
It is anticipated that the acquisitions of such a financial interest will
stimulate the efforts of such employees on behalf of the Company and its
subsidiaries and strengthen their desire to continue in the service of the
Company and its subsidiaries. It is also anticipated that the opportunity to
obtain such a financial interest will prove attractive to promising executive
talent and will assist the Company and its subsidiaries in attracting such
employees.

                  For the purposes of the Plan, the following terms have the
following meanings:

                  (a) "Board" means the Board of Directors of the Company.

                  (b) "Change of Control" has the meaning set forth in
Paragraph 6.

                  (c) "Code" means the Internal Revenue Code of 1986, as
amended.

                  (d) "Committee" means the Committee, as described in
Paragraph 3, which administers the Plan.

                  (e) "Company" means UNR Industries, Inc., a Delaware
corporation, or any successor thereto.

                  (f) "Disability" means a mental or physical condition which
renders a Grantee unable or incompetent to carry out the job responsibilities he
held or tasks to which he was assigned at the time the disability was incurred.

                  (g) "Fair Market Value" means, subject to adjustment as
provided in Paragraph 12, (1) if on the applicable date the Stock is listed for
trading on a national or regional securities exchange or authorized for
quotation on the National Association of Securities Dealers Inc.'s NASDAQ,
National Market System ("NASDAQ/NMS"), the

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closing price of the stock on such exchange or NASDAQ/NMS, as the case may be,
on the applicable date, or if no sales of Stock shall have occurred on such
exchange or NASDAQ/NMS, as the case may be, on the applicable date, the closing
price of the Stock on the next preceding date on which there were such sales,
(2) if on the applicable date the Stock is not listed for trading on a national
or regional securities exchange or is not authorized for quotation on
NASDAQ/NMS, the Fair Market Value of the Stock as determined in good faith by
the Committee, or (3) solely for purposes of determining the benefit payable on
the exercise of a change of control right, the highest value (determined under
clause (1) or (2) above) of one share of Stock during the 180-day period
preceding the date of the Change of Control or, if greater, the highest price
per share of Stock paid in connection with the Change of Control.

                  (h) "Grant Date" means the date set forth on Paragraph 5.

                  (i) "Grantee" means an individual to whom options or change of
control rights are granted under the Plan.

                  (j) "1934 Act" means the Securities Exchange Act of 1934, as
amended.

                  (k) "Option Price" means the purchase price of the Stock
subject to an option as determined under Paragraph 5.

                  (l) "Plan" means the UNR Industries, Inc. Key Executives'
Stock Option Plan as amended from time to time.

                  (m) "Stock" means the shares of common stock of the Company,
par value $.01 per share.

                  2. SCOPE OF THE PLAN. An aggregate of 2,500,000 of the
Company's authorized but unissued shares of Stock is hereby made available and
shall be reserved for issuance under this Plan with respect to the exercise of
options, reduced by the number of shares of Stock acquired to be held as
treasury shares reserved for issuance under this Paragraph 2. An aggregate of
2,500,000 change of control rights is hereby made for issuance under the Plan.
The aggregate number of shares of stock and change of control rights available
under this Plan shall be subject to adjustment on the occurrence of any of the
events and in the manner set forth in Paragraph 12.

                  If, and to the extent, an option shall expire or terminate for
any reason without having been exercised in full, the shares of Stock subject
thereto which have not become outstanding shall (unless the Plan shall have
terminated) become available for other options under the Plan. However, if, and
to the extent, change of control rights are exercised, the shares of Stock
subject to the related option which have not become outstanding shall not again
become available for the grant of other options.

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                  The Board or such person or persons that the Board shall
specifically authorize or direct to act on its behalf shall have the authority
to cause the Company to purchase from time to time, in such amounts and at such
prices as the Board, in its discretion, shall deem advisable or appropriate,
shares of Stock to be held as treasury shares and reserved and used solely for
or in connection with grants under the Plan, at the discretion of the Committee.

                  3. ADMINISTRATION. The Plan shall be administered by the
Compensation Committee of the Board ("Committee"), which shall consist of not
less than three persons, each of whom is a Disinterested Person. "Disinterested
Person" means disinterested person as defined from time to time in Rule 16(b)-3
under Section 16(b) of the 1934 Act or any successor rule promulgated under
section 16(b) of the 1934 Act. The Committee shall have full and final
authority, in its discretion, but subject to the express provisions of the the
Plan:

                  (a) to select eligible employees in accordance with Paragraph
4 to whom options or change of control rights shall be granted;

                  (b) to determine to what extent options and change of control
rights are to be granted under the Plan;

                  (c) to determine the terms and conditions of any option or
change of control rights granted under the Plan;

                  (d) to prescribe the method by which grants of option and
change control rights shall be evidenced;

                  (e) to cancel, with the consent of the Grantee, outstanding
options and change of control rights, and to grant new options and change of
control rights in substitution therefor;

                  (f) to make all other determinations deemed necessary or
advisable for the administration of the Plan;

                  (g) to impose such additional conditions, restrictions, and
limitations upon exercise or retention of options, shares of Stock purchased
pursuant to options and change of control rights as the Committee may, prior to
or concurrently with the grant thereof, deem appropriate;

                  (h) to accelerate the exercisability of any option, subject to
such terms and conditions as the Committee deems necessary arid appropriate to
effectuate the purpose of the Plan; and

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                  (i) at any time prior to the expiration or termination of any
option previously granted, to extend the terms of any option for such additional
period or periods as the Committee, in its discretion, may determine.

                  The determination of the Committee on all matters relating to
the Plan, any option agreement or change of control rights agreement shall be
conclusive and final. No member of the Committee shall be liable for any action
or determination made in good faith with respect to the Plan or any grant
thereunder.

                  4. ELIGIBILITY. Options or change of control rights may be
granted to officers and other key employees of the Company, its subsidiaries,
and affiliates (excluding any person who serves solely as a director of the
Company, one of its subsidiaries, or one of its affiliates).

                  5. GRANTS. The Grant Date of an option or change of control
right shall be the date on which the Committee awards the grant or such later
date as specified in advance by the Committee. Subject to the provisions of
Paragraph 2 and Paragraph 4, a Grantee may, if he is otherwise eligible, be
granted additional options or change of control rights if the Committee shall so
determine. Subject to the other provisions of the Plan, the Committee may grant
options or change of control rights with differing terms and conditions among
the Grantees. To the extent not set forth in the Plan, the terms and conditions
of each grant of an option or change of control rights shall be set forth in a
written agreement between the Company and the Grantee thereof.

                  (a) GRANTS OF NON-QUALIFIED OPTIONS. At the time of the grant
of any option, the Committee shall determine the Option Price of stock subject
to each non-qualified option, provided that the Option Price shall not be less
than the greater of (1) fifty percent (50%) of the Fair Market Value of the
Stock on the Grant Date or (2) the par value of the Stock. The Option Price
shall be reduced (but not below the greater of (i) fifty percent (50%) of the
Fair Market Value of the Stock on the Grant Date, or (ii) the par value of the
Stock) by the amount of any Extraordinary Dividend made after the Grant Date of
the option. "Extraordinary Dividend" means a distribution of the Company's
property to the securityholders as a dividend in partial liquidation, by way of
return of capital, or otherwise, other than a regular periodic cash dividend
payable out of funds legally available for dividends under the laws of the State
of Delaware at an annual rate not in excess of $.20.

                  When granted, a non-qualified option shall be identified with
specific change of control rights of the Grantee equal to the number of shares
of Stock subject to the option. At the time a non-qualified option identified
with change of control rights is exercised, the number of the change of control
rights equal in number to the shares of Stock purchased shall be canceled.

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                  (b) GRANTS OF INCENTIVE STOCK OPTIONS. At the time of the
grant of any option, the Committee may designate that such option shall to be
made subject to additional restrictions to permit it to qualify as an "incentive
stock option" under the requirements of Section 422A (or any successor
provision) of the Code. Any option designated as an incentive stock option

                  (1) shall have an Option Price of (i) not less than 100% of
the Fair Market Value of the Stock on the Grant Date or (ii) in the case of an
employee who owns stock (including stock treated as owned under Section 425(d)
of the Code) possessing more than 10% of the total combined voting power of all
classes of stock of the Company or any of its subsidiaries (a "10% Owner") , not
less than 110% of the Fair Market Value of the Stock on the Grant Date;

                  (2) shall be for a period of not more than ten (10) years,
five (5) years, in the case of a 10% Owner) from the Grant Date, and shall be
subject to earlier termination as herein provided;

                  (3) notwithstanding the provisions relating to termination of
employment set forth in Paragraph 8, shall not be exercisable more than three
(3) months (or one (1) year, in the case of a Grantee who is disabled within the
meaning of Section 22(e)(2) of the Code) after termination of employment;

                  (4) shall not have an aggregate Fair Market Value (determined
for each incentive stock option at the time it is granted) of Stock with respect
to which incentive stock options are exercisable for the first time by such
Grantee during any calendar year (under this Plan and any other employee stock
option plan of the Company or any parent or subsidiary thereof ("Other Plans")),
determined in accordance with the provisions of Section 422A of the Code (after
amendment by the Tax Reform Act of 1986), which exceeds $100,000 (the "$100,000
Limit");

                  (5) shall, if the aggregate Fair Market Value of stock
(determined on the Grant Date) with respect to all incentive stock options
previously granted under this Plan and the other plans ("Price Grants") and any
incentive stock options under such grant (the "Current Grant") which are
exercisable for the first time during any calendar year would exceed the
$100,000 Limit, be exercisable as follows:

                  (i) the portion of the Current Grant exercisable for the first
         time by the Grantee during any calendar year which would be, when added
         to any portions of any Prior Grants exercisable for the first time by
         the Grantee during any such calendar year with respect to Stock which
         would have an aggregate Fair Market Value (determined at the time of
         each such grant) in excess of the $100,000 Limit shall, notwithstanding
         the terms of the Current Grant, be exercisable for the first time by
         the Grantee in the first subsequent calendar year or years in which it
         could

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         be exercisable for the first time by the Grantee when added to
         all Prior Grants without exceeding the $100,000 Limit;

                  (ii) if, viewed as of the date of the Current Grant, any
         portion of a Current Grant could not be exercised under the provisions
         of the immediately preceding sentence during any calendar year
         commencing with the calendar year in which it is first exercisable
         through and including the last calendar year in which it may by its
         terms be exercised, such portion of the Current Grant shall not be an
         incentive stock option, but shall be exercisable as a separate
         non-qualified option at such date or dates as are provided in the
         Current Grant;

                  (6) shall be granted within ten (10) years from the earlier of
the date the Plan is adopted or the date the Plan is approved by the
securityholders of the Company; and

                  (7) shall require the Grantee to notify the Committee of any
disposition of any Stock issued pursuant to the exercise of the incentive stock
option under the circumstances described in Section 421(b) of the Code (relating
to certain disqualifying dispositions), within ten (10) days of such
disposition.

                  (c) GRANT OF CHANGE OF CONTROL RIGHTS. Change of control
rights shall automatically be granted to each Grantee upon the grant of any
non-qualified option under the Plan. Each change of control right shall be
identified with a share of Stock subject to the non-qualified option of the
Grantee and the number of change of control rights granted to a Grantee shall
equal the number of shares of Stock subject to the option with which such change
of control rights are identified. At the time change of control rights of the
Grantee are exercised, a number of shares of Stock subject to the option equal
in number to the change of control rights exercised shall be canceled.

                  (d) NON-TRANSFERABILITY OF OPTIONS AND CHANGE OF CONTROL
RIGHTS. An option or change of control right granted hereunder shall, by its
terms, not be assignable or transferable other than by will or the laws of
descent and distribution and may be exercised, during his lifetime, only by the
Grantee.

                  (e) TERMS OF OPTIONS AND CHANGE OF CONTROL RIGHTS. The term of
each option of change of control right granted hereunder shall be for a period
of no more than ten years from the Grant Date, and shall be subject to earlier
termination as herein provided.

                  6. CHANGE OF CONTROL. For purposes of this Plan, "Change of
Control" means

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                  (a) The acquisition by a person or group of persons acting in
concert, of a beneficial ownership interest in the Company, resulting in the
total beneficial ownership of such persons or group of persons equaling or
exceeding 50% of the outstanding common stock and warrants of the Company;
provided, however, that no such person or group of persons shall be deemed to
beneficially own (i) any common stock or warrants acquired directly from the
Company or (ii) any common stock or warrants held by the Company or any of its
subsidiaries or any employee benefit plan (or any related trust) of the Company
or its subsidiaries. The Change of Control shall be deemed to occur on the date
the beneficial ownership of the acquiring person or group of persons first
equals or exceeds 50% of the outstanding common stock and warrants of the
Company.

                  (b) A change, within any period of twenty-four (24) months or
less, in the composition of the Board such that at the end of such period a
majority of the directors who are then serving were not serving at the beginning
of such period, unless at the end of such period the majority of the directors
in office were nominated upon the recommendation of a majority of the Board at
the beginning of such period. The Change of Control shall be deemed to occur on
the date the last director necessary to result in a Change of Control takes
office or resigns from office, as applicable.

                  (c) Approval by the securityholders of the Company of a
merger, consolidation or other reorganization having substantially the same
effect, or the sale of all or substantially all the consolidated assets of the
Company in each case, with respect to which the persons or group of persons who
were the respective beneficial owners of the common stock or warrants
immediately prior to such event do not, following such event, beneficially own,
directly or indirectly, more than 50% of, respectively, the then outstanding
voting securities of the corporation resulting from such event or the
corporation purchasing or receiving assets pursuant to such event. The Change of
Control shall be deemed to occur on the date on which the transaction is
approved by the Company's Securityholders.

                  If more than one of the foregoing events shall occur, each
such event shall constitute a separate Change of Control.

                  Notwithstanding the foregoing provisions of this Paragraph 6,
a Change of Control shall be deemed not to have occurred with respect to any
event occurring prior to or concurrently with the securityholders' approval of
this Plan.

                  The impact on the Plan of a Change of Control shall be (1) the
acceleration. of the exercisability of options and change of control rights as
provided in Paragraphs 7(b) and (c) and (2) the use for determining the benefit
payable upon exercise of change of control rights of the definition of Fair
Market Value contained on Paragraph 1(g)(3).

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                  The Company shall notify all Grantees of the occurrence of a
Change of Control promptly after its occurrence, but any failure of the Company
to notify shall not deprive the Grantees of any rights accruing hereunder by
virtue of a Change of Control.

                  7. EXERCISE. Except as otherwise determined by the Committee,
and subject to the provisions of Paragraph 8, each option shall be exercisable
as follows:

<TABLE>
<CAPTION>

                                                                      Percentage of Shares of
Year After Grant Date                                                 Stock Exercisable
---------------------------------------------                         -----------------------
<S>                                                                 <C>
         less than one year                                                         0%
         one year but less than two years                                      33-1/3%
         two years but less than three years                                   66-2/3%
         three years or more                                                      100%

</TABLE>

                  Options shall be exercised by delivery to the Company of
written notice of intent to purchase a specific number of shares of stock. The
exercise of a non-qualified option shall cancel a number of change of control
rights identified with such option equal to the number of shares of Stock
purchased upon exercise of the option. The Option Price of any shares of Stock
as to which an option shall be exercised shall be paid in full at the time of
the exercise. Payment of the Option Price shall be made (1) in cash or (2) in
whole or in part, in Stock of the Company held by the Grantee for a period of at
least six months, valued at Fair Market Value.

                  Notwithstanding the foregoing, if the Grantee's employment is
terminated by the Grantee's retirement pursuant to the terms of any
tax-qualified retirement plan of the Company or any of its subsidiaries, or by
the Disability or death of the Grantee, any unexercised options held by the
Grantee on the date of such retirement, Disability or death shall become
immediately exercisable.

                  (b) EXERCISE OF CHANGE OF CONTROL RIGHTS. Subject to the
provisions of Paragraph 8, each change of control right held by a Grantee who is
subject to potential liability for "short-swing" profits under Section 16(b) of
the 1934 Act at the time of a Change of Control shall become exercisable upon
the occurrence of the Change of Control. No change of control right held by any
Grantee who is not subject to potential liability for "short-swing" profits
under Section 16(b) of the 1934 Act at the time of a Change of Control shall
become exercisable upon the occurrence of the Change of Control. The exercise of
change of control rights shall cancel a number of shares of Stock subject to the
option identified with such change of control rights equal to the number of
change of control rights exercised. Change of control rights shall be exercised
by delivery to the Company, within sixty (60) days following the date of such
Change of Control, of written notice of intent to exercise a specific number of
change of control rights.

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                  Within three (3) days following the exercise of any change of
control right, the Company shall pay the Grantee, in cash, an amount equal to
the difference between

                  (1) the Fair Market Value of one share of Stock on the date of
exercise of the change of control right, and

                  (2) the Option Price of the option identified with the change
of control right.

                  (c) ACCELERATED EXERCISE. subject to Paragraph 7(g), all
outstanding options granted hereunder shall be fully exercisable on the date of
a Change of Control.

                  (d) WITHHOLDING TAXES. Whenever under the Plan, shares of
Stock are to be delivered upon exercise of an option the Company shall be
entitled to require as a condition of delivery that the Grantee remit an amount
sufficient to satisfy all federal, state, and other governmental withholding tax
requirements related thereto. A Grantee may, subject to Committee approval,
elect the withholding ("Share Withholding") by the Company of a portion of the
shares of Stock otherwise deliverable to such Grantee upon such Grantee's
exercise of an option having a Fair Market Value equal to

                  (1) the amount necessary to satisfy such Grantee's required
federal, state, or other governmental withholding tax liability with respect to
the exercise of the option, or

                  (2) a greater amount, not to exceed the estimated total amount
such Grantee's tax liability with respect to the exercise of the option.

                  Share Withholding is subject to Committee approval. Each Share
Withholding election by a Grantee shall be subject to the following
restrictions.

                  (1) it shall be made prior to the date on which the amount of
tax to be withheld is determined (the "Tax Date");

                  (2) it shall be irrevocable;

                  (3) it shall be subject to the disapproval of the Committee;

                  (4) if a Grantee is subject to potential liability for
"short-swing" profits under Section 16(b) of the 1934 Act, such election may not
be made within six (6) months after the Grant Date of the related option (except
that this limitation shall not apply if the death or Disability of the
participant occurs prior to the expiration of the six-month period or if, in the
opinion of counsel for the Company, such limitation is unnecessary to satisfy
the requirements of Rule 16B-3 under Section 16(b) of the 1934 Act or the rules
of any exchange on which the Stock is listed for trading; and

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                  (5) If a Grantee is subject to potential liability for
"short-swing" profits under Section 16(b) of the 1934 Act, such election must he
made either six (6) months prior to the Tax Date or in the ten business day
"window period" beginning on the third business day following the release of the
Company's quarterly or annual summary statement of sales and earnings, unless,
in the opinion of counsel for the Company, such limitation is unnecessary to
satisfy the requirements of Rule 16b-3 under Section 16(b) of the 1934 Act or
the rules of any exchange on which the Stock is listed for trading.

                  If any disqualifying disposition described in Paragraph 5(b),
(7) or any election described in Paragraph 7(e) is made, then the person making
such disposition or election shall remit to the Company an amount sufficient to
satisfy all federal, state, and other governmental withholding taxes thereby
incurred; provided that, in lieu of or in addition to the foregoing, the Company
shall have the right to withhold such sums from compensation otherwise due to
such person.

                  (e) NOTIFICATION UNDER SECTION 83(b). Provided that the
Committee does not prohibit such Grantee from making the following election, if
a Grantee shall in connection with the exercise of any option make the election
permitted under Section 83(b) of the Code (i.e., an election to include in such
Grantee's gross income in the year of transfer the amount specified in section
83(b) of the Code), then such Grantee shall notify the committee of such
election within ten (10) days of filing notice of the election with the Internal
Revenue Service, in addition to any filing and notification required pursuant to
regulations issued under the authority of Section 83(b) of the Code.

                  (f) STOCK PURCHASED FOR INVESTMENT. Shares of Stock purchased
under an option shall be purchased for investment and without present intention
of resale and the certificates representing such Stock shall bear an appropriate
legend, unless, in the opinion of counsel for the Company, the shares may be
purchased without investment representation. Where an investment representation
is deemed necessary, the Committee may require a written representation to that
effect by the Grantee at the time the option is exercised.

                  (g) SPECIAL RULES FOR OFFICERS AND DIRECTORS. No officer or
director shall exercise an option identified with change of control rights or
change of control rights for six months from the Grant Date of such options or
change of control rights except that this limitation shall not apply in the
event the death or Disability of the Grantee occurs prior to the expiration of
the six-month period or if, in the opinion of counsel for the Company, such
limitation is unnecessary to satisfy the requirements of Rule 16b-3 under
Section 16(b) of the 1934 Act or the rules of any exchange on which the Stock is
listed for trading.

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                  8. TERMINATION OF EMPLOYMENT. Except as provided below or as
determined by the Committee, an unexercised option shall terminate upon the
Grantee's termination of employment. Termination of employment means the first
date the Grantee is no longer an employee of the Company or any of its
subsidiaries or, with respect to a Grantee who is an employee of a subsidiary of
the Company, on the first date on which the Company no longer (directly or
indirectly) owns shares of stock conferring at least fifty percent (50%) of the
aggregate voting power of such subsidiary's outstanding stock (both events
hereunder are referred to as "termination of employment").

                  (a) Except as provided in (b) and (c), any unexercised options
previously granted to the Grantee and otherwise exercisable on such Grantee's
termination of employment may be exercised, in whole or in part, at any time
within six months after the Grantee's termination of employment

                  (b) If such employment is terminated by death of the Grantee,
any unexercised options on the date of death may be exercised, in whole or in
part, at any time within 18 months after the date of death by the Grantee's
personal representative or by the person to whom the option is transferred by
will or the applicable laws of descent and distribution; and

                  (c) If such employment is terminated by reason of the
Grantee's retirement pursuant to the terms of any tax-qualified retirement plan
of the Company or any of its subsidiaries or Disability of the Grantee, any
unexercised options on the date of such retirement or Disability may be
exercised, in whole or in part, at any time within 18 months after date of such
termination of employment, provided that, if such person dies after such
termination of employment, and before the expiration of the 18-month period,
such options may be exercised by the deceased Grantee's personal representative
or by the person to whom the options are transferred by will or the applicable
laws of descent and distribution within such 18-month period.

                  Any unexercised change of control right exercisable on the
Grantee's termination of employment shall remain exercisable until the end of
the sixty-day period provided for in Paragraph 7(b).

                  Any of the provisions of this Paragraph 8 to the contrary
notwithstanding, in no event shall any option or change of control right be
exercised after ten years from the Grant Date.

                  9. NO EMPLOYMENT RIGHTS. Neither the establishment of, nor the
awarding of options or change of control rights under, the Plan shall be
construed to give any employee the right to be retained in the Company's (or any
of its subsidiaries') service or to any benefits not specially provided by the
Plan, or to modify in any manner the Company's right to modify, amend or
terminate any of its pension or retirement plans.

                                       11
<PAGE>

                  10. NATURE OF PAYMENTS. Any and all grants of options or
change of control rights or deliveries of shares of Stock hereunder shall
constitute special incentive payments to the Grantee and shall not be taken into
account in computing the amount of salary or compensation of the Grantee for the
purposes of determining any pension, retirement, death or other benefits under
(a) any pension, retirement, profit-sharing, bonus, life insurance or other
employee benefit plan of the Company or any of its Subsidiaries, or (b) any
agreement between the Company or any of its subsidiaries and the Grantee, except
as such plan or agreement shall otherwise expressly provide.

                  11. STOCKHOLDERS' RIGHTS. A Grantee shall not, by reason of
any options or change of control rights granted hereunder, have any right of a
stockholder of the Company with respect to the shares of Stock subject to his
options.

                  12. ADJUSTMENTS. Any option agreement or change of control
rights agreement entered into hereunder shall contain provisions for equitable
adjustment of

                  (a) the number, class, and series of shares of stock subject
thereto, or

                  (b) the Option Prices,

to reflect a stock dividend, stock split-up, share combination,
recapitalization, merger, consolidation, asset spin-off, reorganization, or
similar event, of or by the Company. In any such event, regardless of whether
specified in an option agreement or change of control rights agreement, the
aggregate number, class and series of shares of stock and change of control
rights available under the Plan, the number, class and series of shares of stock
subject to the option agreement, or the Option Price shall be appropriately
adjusted to equitably reflect such event.

                  13. AMENDMENT OF THE PLAN. The Board may not amend the Plan
without further approval of the securityholders of the Company, unless, in the
opinion of counsel for the Company, such approval is unnecessary to satisfy the
requirements of Rule 16B-3 under Section 16(b) of the 1934 Act or the rules of
any exchange on which the Stock is listed for trading and except as provided in
Paragraph 12.

                  14. TERMINATION OF THE PLAN. The Plan shall terminate ten
years after the Effective Date, or at such earlier time as the Board may
determine. Any termination, whether in whole or in part, shall not effect any
options or change of control rights then outstanding under the Plan.

                  15. SUBSTITUTED OPTIONS. If the Committee cancels, with the
consent of a Grantee, any options granted under this Plan, and a new option is
substituted therefor, then the Committee may, in its discretion, provide that
the Grant Date of the canceled option (other than an option subject to the
restrictions of paragraph 5(b)), shall (subject to

                                       12
<PAGE>

the provisions of Paragraph 7(g)) be the date used to determine the earliest
date for exercising the new substituted option under Paragraph 7 so that the
Grantee may exercise the substituted option at the same time as if the Grantee
had held the substituted option since the Grantee Date of the canceled option.

                  16. FUNDING. Benefits payable under the Plan to any person
shall be paid directly by the Company. The Company shall not be required to
fund, or otherwise segregate assets to be used for payment of, benefits under
the Plan.

                  17. CONTROLLING LAW. The law of the State of Illinois, except
its law with respect to choice of law, shall be controlling in all matters
relating to the Plan.

                  18. ACTION BY THE COMPANY. Any action required by the Company
under the Plan shall be by resolution of the Board.

                                       13<PAGE>

                                                                   Exhibit 10.13

                                      [LOGO]

                          COMMONWEALTH OF PENNSYLVANIA

                     INTEGRATED VOICE AND DATA RADIO SYSTEM

                             STATEWIDE RADIO SYSTEM
                                SITE DEVELOPMENT
                                     BETWEEN
                     THE GOVERNOR'S OFFICE OF ADMINISTRATION
                          COMMONWEALTH OF PENNSYLVANIA
                                       AND
                  ROHN CONSTRUCTION, INC., A TEXAS CORPORATION
                             CONTRACT NO. ME 950102

<PAGE>

                                 CONTRACT FOR A
                     STATEWIDE RADIO SYSTEM SITE DEVELOPMENT
                                     BETWEEN
                     THE GOVERNOR'S OFFICE OF ADMINISTRATION
                          COMMONWEALTH OF PENNSYLVANIA
                                       AND
                  ROHN CONSTRUCTION, INC., A TEXAS CORPORATION

                             CONTRACT NO. ME 950102

This Contract ("Contract"), made and entered into this 23rd day of November,
1999, at Harrisburg, PA, in the County of Dauphin, Commonwealth of Pennsylvania,
by and between the Commonwealth of Pennsylvania, Governor's Office of
Administration, with offices in the Finance Building, Harrisburg, PA,
(hereinafter the "Commonwealth"), and Rohn Construction, Inc., a Texas
corporation, with offices at 6178 W. Plank Road, Peoria, Illinois acting through
its proper officials (Rohn hereinafter referred to as the "Contractor"). The
Commonwealth and the Contractor are hereinafter collectively called the
"Parties".

WITNESSETH THAT:

         WHEREAS, the Commonwealth has need of a Statewide Radio System Site
Development, training, support and initial maintenance hereinafter defined as
the "System"; and,

         WHEREAS, the Commonwealth has made known its requirements for the
System through issuance of a Request For Proposal No. RFP # 1998-SD-1, dated
December 4, 1998 and subsequent Addenda; and

         WHEREAS, by Act 1996-148, the Capital Budget for Fiscal Year 1996-1997,
the General Assembly of the Commonwealth authorized the development of a
Statewide Mobile Radio and Microwave System as a public improvement project and
further authorized the Governor's Office of Administration to solicit and award
such contracts as may be necessary for the project; and,

         WHEREAS, the Contractor has made known to the Commonwealth, through
submission of a proposal, dated March 12, 1999, and that the Contractor has
available the system, equipment, training, support and maintenance and the
ability to furnish the System which the Contractor is willing to make available
to the Commonwealth in accordance with the terms and conditions hereinafter
contained in this Contract:

<PAGE>

         NOW, THEREFORE, for and in consideration of the foregoing premises and
the mutual promises hereinafter set forth, the Parties hereto agree, with the
intention of being legally bound, as follows:

1.   The Contractor will furnish the System, with associated equipment, and as
     applicable, install and maintain the System and provide training and
     support services in accordance with the terms and conditions described
     hereinafter, and in the following RIDERS which are hereby incorporated by
     reference and made a part hereof:

         RIDER A  --       TERMS AND CONDITIONS
         RIDER B  --       STATEMENT OF WORK AND DELIVERABLES
         RIDER C  --       EQUIPMENT LIST AND CHARGES
         RIDER D  --       PROJECT SCHEDULE
         RIDER E  --       MILESTONE PAYMENT PLAN
         RIDER F  --       WARRANTY AND MAINTENANCE AGREEMENT
         RIDER G  --       PERFORMANCE BOND
         RIDER H  --       ACCEPTANCE TESTING

2.   The Commonwealth will, in compliance with RIDERS A through H attached
     hereto, the Commonwealth's Request For Proposal, and the Contractor's
     Proposal, incorporated herein by reference, pay to the Contractor the
     compensation for the System and ancillary service as therein specified.

3.   This Contract is a firm fixed price ordering agreement, with an estimated
     total cost to the Commonwealth for this Contract in an amount not to exceed
     $ 40,000,000.00. In addition, other entities and political subdivisions may
     make eligible purchases under Paragraph A.65 of Rider A of this Contract in
     an amount to be determined.

<PAGE>

IN WITNESS WHEREOF, the Parties to this Contract have executed it through their
respective duly authorized offices, to be effective as of the date first above
written. This Contract will not be binding on the Parties unless and until all
signatures are affixed hereto.

ATTEST:                                     Rohn Construction, Inc.
BY:_________________________________        BY:  ___________________
NAME:                                       NAME: Brian B. Pemberton

TITLE:                                      TITLE: President and Chief Executive
                                                   Officer
DATE: _________, 1999                       DATE: ____________, 1999
                                            FED TAX ID NO: ____________

                                            Commonwealth
                                            COMMONWEALTH OF PENNSYLVANIA:
WITNESS:                                    OFFICE OF ADMINISTRATION
BY: ________________________________        BY: _______________________________
NAME: _____________________________         NAME: _____________________________
TITLE: _____________________________        TITLE: ____________________________
DATE: _____________________________         DATE: _____________________________

APPROVED FOR FORM AND LEGALITY:             CERTIFICATION OF FUNDS:
                                            I HEREBY CERTIFY THAT FUNDS
____________________________________        ARE AVAILABLE IN THE AMOUNT
OFFICE OF GENERAL COUNSEL  DATE             OF $ ___________________________.
                                            ________________________________
                                            COMPTROLLER      DATE
____________________________________        APPROVED:
OFFICE OF ATTORNEY GENERAL DATE             SECRETARY OF THE BUDGET

                                            BY: ______________________________
                                            COMPTROLLER               DATE

<PAGE>

RIDER A  Terms & Conditions, including Definitions
RIDER B  Statement of Work & Deliverables with Installation Standards
RIDER C  Equipment List and Charges
RIDER D  Project Schedule
RIDER E  Payment Schedule
RIDER F  Warranty, Maintenance, & Support
RIDER G  Performance Bond
RIDER H  Acceptance Testing

A.1      DEFINITION OF TERMS
----------------------------

     A.   ACCEPTANCE DATE - The date on which the Commonwealth agrees in writing
          that a particular Site or Subsystem has successfully passed the
          appropriate Acceptance Test Procedure as defined in Rider H.

     B.   ACCEPTANCE TESTING - Testing as defined in Rider H, conducted by the
          Contractor, and witnessed by the Commonwealth, to validate compliance
          with this Contract.

     C.   ADDITIONAL EQUIPMENT - Equipment added during the term of this
          Contract, and any extension, which supplements the Equipment in Rider
          C.

     D.   ALTERATION - Any material change to the System which deviates from the
          Contractor's physical, mechanical, civil, software, or electrical
          design whether or not additional devices or parts are required.

     E.   BENEFICIAL USE - Application of a Site or Subsystem as a means of
          supporting wireless communications by the Commonwealth, following
          written notification to the Contractor by the Commonwealth of the date
          that such use of the Site or Subsystem will begin. Beneficial use
          shall not begin prior to such written notice.

     F.   CONTRACT IMPLEMENTATION REVIEW (CIR) - Meeting conducted to review all
          system and performance requirements as defined in Rider B.

     G.   COMPONENT - An individual unit, part, hardware, assembly, accessory,
          feature, function, or supporting software, whether or not separately
          identified by type and/or model number in Rider C.

     H.   CRITICAL DESIGN REVIEW (CDR) - Meeting conducted for system-level
          review as defined in Rider B.

     I.   DOCUMENTATION - The then-current standard informational materials
          provided in digital form, if available, published by the Contractor
          and made available for the Commonwealth's use with the Site, a
          Subsystem, or Component as defined in Rider B.

     J.   DETAILED DESIGN DOCUMENT (DDD) - Final System documentation submitted
          by the Contractor to the Commonwealth at the time of Final System
          Acceptance.

     K.   ENGINEERING AND QUALITY ASSURANCE CONTRACTOR (EQAC) - The entity
          designated by the Commonwealth to coordinate the overall activities
          and schedules of the prime contractors for the System.

<PAGE>

     L.   EQUIPMENT - Any item or items listed in Rider C.

     M.   EQUIPMENT FAILURE - An all-inclusive term that pertains to failure of
          any Subsystem, Component, supporting software, or Site function or
          feature.

     N.   FACTORY WARRANTY - The Contractor's standard commercial warranty as
          outlined in Rider F.

     O.   FACTORY ACCEPTANCE TESTING - The process identified in Rider H as the
          testing procedure for a subsystem assembled at the Staging Area.

     P.   FACTORY STAGING AREA - The location, designated by the Contractor and
          approved by the Commonwealth, that is the Contractor's final factory
          assembly area for Subsystems or Equipment during testing by the
          Commonwealth prior to shipment.

     Q.   FIELD MODIFICATION - Any change to the specifications of a Component,
          Subsystem, or the System which is performed where the System is
          installed at a Commonwealth location, as opposed to returning the
          Component to a factory or other non-Commonwealth location for such
          changes.

     R.   FISCAL YEAR/PERIOD - For the purpose of this Contract the Fiscal Year
          of the Commonwealth is twelve (12) consecutive months beginning July 1
          and ending June 30.

     S.   HOLIDAYS - Those non-working weekdays so identified in Rider B.

     T.   INOPERATIVE COMPONENT - A Component or Subsystem which does not comply
          with the applicable operational and technical specifications.

     U.   INSTALLATION - The provision of Components, Equipment, Subsystems,
          and/or services by the Contractor to make Equipment supplied from
          Rider C fully functional and complete in accordance with Rider B and
          this Contract.

     V.   INSTALLATION DATE - The work day following the day the System or
          aSubsystem is installed and capable of functioning to manufacturer's
          published specifications and is certified by the Contractor as Ready
          For Acceptance Testing.

     W.   INTERCONNECTION - The mechanical, electrical, radio frequency, or
          electronic interconnection to a Contractor-supplied Subsystem or Site
          of Components or Subsystems not supplied by the Contractor.

     X.   MAINTENANCE - Optional equipment and services as detailed in Rider F
          provided by the Contractor to support Equipment acquired under this
          Contract.

     Y.   MICROWAVE AGREEMENT - The contract entered into by the Commonwealth
          with the entity that will supply and install the microwave
          point-to-point radio links.

     Z.   PRELIMINARY DESIGN REVIEW (PDR) - Formal collective engineering
          presentation and analysis held as specified in Rider B.

     AA.  PRODUCTS - Equipment, Systems, Subsystems, Components, documentation,
          and software described in this Contract.

     BB.  PROPOSAL - Contractor's Proposal to the Commonwealth dated
          ___________.

<PAGE>

     CC.  PROPRIETARY INFORMATION - Any data, information, software, or
          intelligence, including corrections, modifications, revisions and
          copies thereof, whether digital form or visually readable containing
          information which is the property of, and is confidential to the
          Contractor and/or its licensors, and is designated by the Contractor
          as proprietary.

     DD.  READY FOR ACCEPTANCE TESTING - The point in time at which the Site,
          or a Subsystem, is installed and certified by the Contractor, in
          writing, to the Commonwealth that all operational and technical
          specifications are met and that Acceptance Testing can begin.

     EE.  READY FOR USE - The point in time at which the Site or a Subsystem is
          installed and has completed Acceptance Testing.

     FF.  REGION - A geographical area so identified by the Commonwealth
          comprised of a group of Equipment and Components that constitute a
          functional group.

     GG.  REPLACEMENT - The exchange or substitution of a Component, Equipment,
          or Subsystem for another due to its malfunction or inability to
          function according to its published specifications.

     HH.  REQUEST FOR DESIGN - A written notification to the Contractor from the
          Commonwealth that the Contractor shall proceed with generation of Site
          Equipment designs for consideration by the Commonwealth.

     II.  RFP - The Commonwealth's Request for Proposals No.: RFP #1998-SD-1,
          dated _________, 1998 and subsequent Addenda.

     JJ.  SERVICES - The furnishing of the effort by the Contractor necessary to
          implement or support the System. Examples include, but are not limited
          to, installation, training, maintenance, warranty, engineering or
          other professional, technical, consultative, programming, and
          analytical services not specified elsewhere in this Contract.

     KK.  SITE - The location(s) where Equipment is to be installed.

     LL.  SITE ACCEPTANCE TESTING - The process identified in Rider H as the
          testing procedure for a Site following completion and successful
          acceptance testing of all Subsystems.

     MM.  SITE DEPLOYMENT ORDER (SDO) - A written notification to the Contractor
          from the Commonwealth that the Contractor may proceed with
          Installation at a particular Site or Sites in accordance with Riders
          B, D and H.

     NN.  SITE DESIGN DOCUMENT (SDD) - A Contractor deliverable outcome of the
          SDR and its associated process as submitted to the Commonwealth for
          its approval.

     OO.  SITE PRODUCTION RELEASE (SPR) - Written confirmation from the
          Commonwealth to the Contractor in response to an approved SDD
          notifying the Contractor to proceed with acquisition and staging of a
          Site, Sites, or Subsystems detailed in either the approved SDD, or in
          a design of the Commonwealth's choosing.

<PAGE>

     PP.  SITE DESIGN REVIEW (SDR) - Formal analysis and evaluation of a
          Contractor-submitted proposed SDD as defined in Rider B.

     QQ.  SITE PREPARATION - The activities to be performed in preparing the
          physical location(s) at a Site for the installation of the Site
          Equipment and Subsystems.

     RR.  SOFTWARE - All computer or microprocessor instructions that the
          Contractor is to supply. This includes, but is not limited to,
          operating systems, programs, routines, application systems,
          subroutines, translators, compilers, and related items.

     SS.  SUBSTITUTE EQUIPMENT - Alternate(s) for Equipment, Component(s), or
          Subsystem(s) listed in Rider C that are acceptable to the
          Commonwealth, have at least equal capabilities or greater capabilities
          at the Contractor's option, are capable of performing the functions of
          the original in accordance with this Contract's specifications and
          operational requirements, and are supplied to the Commonwealth at
          equal or lower cost than listed for the original in Rider C.

     TT.  SUBSYSTEM - A complement of individual Components, Equipment, and
          Software designated and acquired by the Commonwealth through this
          Contract to operate as an integrated and functional part of a Site.
          Subsystems include but are not limited to: towers, equipment shelters,
          generators, battery plants, and site development.

     UU.  SITE ACCEPTANCE TESTING - The process identified in Rider H as the
          testing procedure for a Site or Sites following completion of
          Installation of all supplied Equipment and Subsystems.

     VV.  SYSTEM - The total complement of individual Components, Equipment,
          Subsystems and Software which are being acquired through this Contract
          to operate as the entire Statewide System.

     WW.  SYSTEM FAILURE - See EQUIPMENT FAILURE.

     XX.  SYSTEM WARRANTY - The two-year period, beginning on the date the
          Commonwealth notifies the Contractor in writing that the System has
          successfully completed Final Acceptance Testing in Rider H, during
          which the Contractor provides ongoing System technical support as
          specified in Rider F.

A.2 GENERAL PURPOSE

The purpose of this Contract is to obtain Site Design Documentation, Site
Preparation, Installation, Equipment and Services, as defined herein.

A.3 TERM OF CONTRACT

The term of this Contract shall begin on the date that this Contract is fully
executed and approved and shall expire, unless earlier terminated pursuant to
the Contract, when the Contractor has performed all of its obligations under
this Contract including the ongoing obligations as specified in this Contract
and in the Proposal and the Contractor has received payment in full.

A.4 CONTRACT DOCUMENTS AND ORDER OF PRECEDENCE

<PAGE>

This Contract includes its attachments, the RFP and the Contractor's Proposal,
and addenda as though they were fully stated herein. In the event of a dispute
of terms or interpretation, the order of control shall be the Contract, the
Proposal, and then the RFP.

A.5 INTEGRATION PROVISION

This Contract, as above defined, constitutes the entire agreement between the
Parties with regard to the subject matter of this Contract, and it supersedes
any prior agreements, understandings or other arrangements not incorporated
herein. No agent, representative, employee or officer of either the Commonwealth
or the Contractor has authority to make, or has made, any statement, agreement
or representation, oral or written, in connection with this Contract, which in
any way can be deemed to modify, add to or detract from, or otherwise change or
alter its terms and conditions. No negotiations between the parties, nor any
custom or usage, shall be permitted to modify or contradict any of the terms and
conditions of this Contract. No modifications, alterations, changes or waiver to
this Contract or any of its terms shall be valid or binding unless accompanied
by a written amendment signed by both parties. All such amendments or
modifications will be made using the appropriate Commonwealth form.

A.6 OVERALL DESIGN PROCESS

     A.   The Contractor and the Commonwealth shall jointly conduct the
          following formal Reviews as further defined in Rider B:

          i.   Contract Implementation Review

          ii.  Preliminary Design Review

          iii. Critical Design Review

          iv.  Regional Design Reviews

     B.   System designs submitted by the Contractor shall conform to the
          Commonwealth's requirements for Site Development as defined in the RFP
          document and in Rider B.

     C.   Designs shall provide the functions, services, and performances
          outlined in the RFP document, in Rider B, and further detailed in each
          of the Reviews in A.6A.

A.7 REGIONAL DESIGN PROCESS

<PAGE>

     A.   Contractor shall proceed with design of each Site in each Region in
          response to a written Request for Design from the Commonwealth.
          Regions shall be designed in an order determined by the Commonwealth.

     B.   The Commonwealth shall confirm in writing to Contractor any specific
          exceptional needs or requirements for any Site or the set of Sites
          within the Region. This confirmation shall consist only of those needs
          or requirements that are exceptions to those noted in paragraph A.6
          above.

     C.   The Commonwealth shall supply Contractor with all such specific
          information noted in Rider B regarding each Site that is available to
          the Commonwealth.

     D.   Contractor shall, upon receipt of the information noted in the
          paragraphs above, review the information for completeness. Contractor
          shall notify the Commonwealth immediately of any missing information
          required prior to Contractor proceeding with design efforts.

     E.   Contractor acknowledges that Site selection responsibility and
          authority rests with the Commonwealth

A.8 SITE DESIGN PROCESS

     A.   All Contractor Site design efforts shall include the Commonwealth and
          the Commonwealth's Engineering and Quality Assurance Contractor as
          active participants.

     B.   Contractor shall, upon receipt of the Commonwealth's written Request
          for Design, perform such field, engineering, professional, or
          production investigative and/or design efforts as required. A.6B

     C.   Contractor shall supply the Commonwealth, as a deliverable prior to
          each Site Design Review, Site and Subsystem designs submitted as the
          proposed Site Design Document. Each proposed SDD shall include, at a
          minimum, the following:

          i.   Site Survey (including, as appropriate; geotechnical reports,
               survey results, stress analysis, foundation analysis, and other
               engineering or professional reports)

          ii.  Design Parameters

          iii. List of Components, Equipment, and Subsystems Required

          iv.  Draft engineering drawings, schematics, and layouts sufficient
               for the Review

          v.   Proposed Site Installation Schedule

          vi.  Itemized listing of Costs, reconciled to Rider C

          vii. Itemized list of Options, including the impact of Options on
               those items above

     D.   The Contractor, the Commonwealth, and the Commonwealth's EQAC shall
          jointly

<PAGE>

          review the proposed SDD and determine the efficiency, completeness,
          suitability and appropriateness of the design. The proposed SDD shall
          be modified during this process, as determined by the participants, to
          best meet the Commonwealth's design objectives.

     E.   The Commonwealth and the Contractor shall both sign the revised design
          document as indication of their agreement that the design meets the
          requirements of paragraph A.6. Upon signature by both the Commonwealth
          and the Contractor, the document becomes the Site Design Document
          (SDD) for its Site.

A.9  ACQUISITION AND STAGING

     A.   The Contractor shall proceed with Site Preparation and Fabrication or
          Acquisition of Equipment or Subsystems following receipt by the
          Contractor of a written Site Production Release (SPR) from the
          Commonwealth.

     B.   The Contractor shall notify the Commonwealth when Equipment or a
          Subsystem is available for Factory Acceptance Testing, as required and
          as appropriate. The Contractor shall deliver required documentation
          concurrent with notification to the Commonwealth that Equipment or a
          Subsystem is available for Factory Acceptance Testing as described in
          Rider B.

A.10 INSTALLATION

     A.   The Contractor shall proceed with Installation of Equipment or
          Subsystems following receipt by the Contractor of a written Site
          Deployment Order (SDO) from the Commonwealth.

     B.   Following receipt of each SDO, the Contractor shall install the
          applicable Site and/or Subsystems as specified in the SDO and make
          them available for Site Acceptance Testing as specified in Rider H.

     C.   The Contractor shall notify the Commonwealth in writing of the
          completion of each Site Installation.

     D.   Installation Dates may be changed by mutual consent of the Contractor
          and the Commonwealth in writing. However, consent of the Contractor is
          not required if, at least thirty (30) days prior to the Installation
          Date of any Site or Subsystem, the Commonwealth directs in writing a
          later Installation Date for such Site or Subsystem. In either event
          the SDO shall be modified in writing, accordingly. Any period of
          mutually agreed upon delay, or Commonwealth directed delay, which
          results in changes to other related dates contained herein shall not
          be subject to liquidated damages as specified in paragraph A.13 of
          this Contract.

A.11 ACCEPTANCE TESTING

     A.   Acceptance Testing shall be scheduled by mutual agreement as soon as
          practicable

<PAGE>

          following completion of Installation of the Site or Subsystem as
          detailed in Riders B and H. Acceptance Testing may proceed by Site or
          Subsystem at the Commonwealth's option.

     B.   The Commonwealth, the EQAC, or the Commonwealth's designee shall
          attend all Acceptance Testing of Sites and Subsystems. Contractor
          shall provide the Commonwealth with a minimum of fourteen (14)
          calendar days written advance notice of the location, date, and time
          of such Acceptance Testing. Immediately upon successful completion of
          such Acceptance Testing, the Commonwealth shall notify the Contractor
          in writing that the Contractor has passed the applicable Acceptance
          Test and authorize the payment of applicable charges per Rider E.

     C.   If the Commonwealth does not accept or approve of an initial
          Acceptance Test, or the Site, Subsystem(s), or Equipment do not pass
          the Acceptance Test, the Contractor shall submit the results of that
          Acceptance Test in writing to the Commonwealth along with a report of
          its efforts to correct the cause or causes of Acceptance Test failure.
          The Commonwealth shall have thirty (30) calendar days after its
          receipt of such results to notify the Contractor in writing of
          acceptance of the Site or Subsystem and authorize the payment of
          applicable charges, or to schedule a repeat Acceptance Test.

     D.   The Commonwealth is under no obligation to accept ownership, make
          progress or other payments, or acknowledge receipt of any equipment
          until successful completion of all applicable Acceptance Test
          Procedures as defined in Rider H.

     E.   The Commonwealth may, at its option, accept a Site or Subsystem prior
          to successful completion of Acceptance Testing, recognizing that some
          discrepancies exist. These discrepancies shall be compiled and listed
          at the time of Acceptance Testing and acknowledged by the contractor
          on what is commonly referred to as a "punch list". Before the
          Commonwealth shall exercise this option, an agreement in writing shall
          be established between the Commonwealth and the contractor stating
          that the contractor shall make all corrections noted on the punch list
          by the date agreed to. If the contractor fails to make correction of
          all deficiencies noted on the punch list on the date specified, the
          Commonwealth may take appropriate legal action against the contractor,
          and the surety company under the performance bond, for damages
          incurred by the Commonwealth.

     F.   If successful completion of repeated Acceptance Testing is not
          attained within one hundred twenty (120) days of the Installation
          Date, the Commonwealth shall have the option of terminating this
          Contract, or continuing repeated Acceptance Tests. The Commonwealth's
          option to terminate this Contract shall remain in effect until such
          time as a successful completion of the Acceptance Testing is attained.
          If termination occurs, the Contractor shall be liable for all inbound
          and outbound preparation and shipping costs for contracted items
          returned.

     G.   After a Site or Subsystem has completed a successful Acceptance Test,
          a Site or Subsystem which:

<PAGE>

          i.   is field modified from one model to another; or,

          ii.  is installed as a Replacement by the Contractor,

          shall be subject to a new original Acceptance Test, which shall be in
          accordance with the provisions of this paragraph, but independently of
          other Sites or Subsystems in the System. The Commonwealth and the
          Contractor jointly shall maintain appropriate records to satisfy the
          requirements of this paragraph.

A.12 TERMS OF PAYMENT AND BILLING

     A.   Contractor shall send and receive all correspondence and submittals
          under this Contract in electronically usable format as follows:

          i.   Contractor shall submit all invoices, equipment delivery
               statements, and production submittals electronically using the
               software program EXPEDITION by Primavera, Inc., in its most
               recent commercially available version. Such submittals shall use
               conventions, accounts, formatting, and methods of submittal as
               specified by the Radio Project Office.

          ii.  All Contractor schedule and milestone submittals shall use the
               software program SURETRAK by Primavera, Inc.

          iii. Contractor shall submit all drawings in a format compatible with
               AUTOCAD by AutoDesk, Inc.

     B.   Contractor shall prepare a submittal showing milestones completed,
          along with supporting documentation, for approval by the Commonwealth
          Project Director. Such submittal shall reflect the milestones achieved
          to include the last day of the proceeding month. Payment shall be due
          based on the completion of each milestone specified in Rider E, minus
          any sums to be withheld. The Contractor shall submit invoices for
          completed service each month to the Commonwealth's EXPEDITION server
          per paragraph A above.

     C.   Payments under this Contract shall be based on Contractor's
          accomplishment of milestones. These milestones and the percent of
          applicable payment to be made to Contractor are specified in Rider E.

     D.   A proper invoice must include the following information and/or
          attached documentation:

          i.   Name and address of business concern as designated in the
               Contract.

          ii.  Federal Tax Identification Number of business concern as
               designated in the Contract.

          iii. Invoice remittance address as designated in the Contract.

<PAGE>

          iv.  Description including time period, serial numbers, sites,
               subsystems, and services and deliverables actually rendered or
               delivered as specified in the Statement of Work.

          v.   The Contract number.

          vi.  Work sheets detailing materials provided and tasks performed.

     E.   If an invoice contains a defect or impropriety and/or it is not a
          proper invoice, as defined in this section, a written notification and
          the improper invoice shall be sent to the business concern at the
          address designated for Receipt of Notices within ten (10) calendar
          days. The notice shall contain a description of the defect or
          impropriety and any additional information necessary to correct the
          defect or impropriety. If such notification has been sent, the
          required payment date shall be thirty (30) days after the receipt of a
          proper invoice in accordance with this section.

     F.   Payments under the Contract will be due and payable on the thirtieth
          (30th) calendar day after the date of actual receipt of a proper
          invoice in the office designated to receive the invoice, or the date
          the Commonwealth receives acknowledgement of a completed milestone in
          accordance with the terms of the Contract, whichever is later. The
          date of the warrant issued in payment shall be considered the date
          payment is made. Contractor payment shall not be initiated before an
          invoice is received. If Contractor is a designated small business,
          Management Directive 305.7 Amended, June 12, 1986 shall apply.

     G.   Payment by wire transfer is permitted upon receipt of wire transfer
          instructions from the Contractor.

A.13 LIQUIDATED DAMAGES

     A.   The installation dates set forth in the SDOs will be fixed in such a
          manner that the integration of the System is consistent with the
          timing and schedules of the Commonwealth's programs. If the Contractor
          does not complete Installations within the time limits specified in
          the SDOs, the delays will interfere with the proper implementation of
          the Commonwealth's System and with coordination between the various
          contractors installing the system to the loss and damage of the
          Commonwealth. From the nature of the case it would be impractical and
          extremely difficult to fix the actual damage sustained in the event of
          any such action. The Commonwealth and the Contractor, therefore,
          presume that in the event of any such delay the amount of damage
          sustained from the delay will be the amount set forth in this
          paragraph. They further agree that in the event of any such delay, the
          Contractor shall pay such amount as liquidated damages and not as a
          penalty; and that such liquidated damages are in lieu of all other
          damages arising from such delay. The Commonwealth is not obligated for
          payment of liquidated damages under the terms of this Contract.

<PAGE>

     B.   If the Contractor does not meet the Installation Date(s) of the
          SDO(s), the Contractor shall pay the Commonwealth, as fixed and agreed
          liquidated damages for each calendar day between the required
          Installation Date and the actual Installation Date, but not for more
          than one hundred eighty (180) calendar days in any instance, in lieu
          of all other damages due to such non-installation, an amount of 0.05%
          (0.0005) daily of the purchase price including maintenance, but less
          the purchase price applicable to installed Components, for each
          Subsystem rendered inoperable as a result of such delay in Ready for
          Use.

     C.   Delays of the contractor in meeting scheduled Installation Date for a
          Site, a Subsystem, or the System as specified in the SDO shall result
          in a loss to the Commonwealth of 0.05% (0.0005) per day of the
          purchase price, for a maximum of 180 working days for each subsystem
          rendered inoperable as a result of each calendar day delay in
          completing the tasks. An extension of time granted by the Commonwealth
          shall not be construed as a waiver of liquidated damages unless such
          extension shall specifically provide such waiver.

     D.   If the delays are caused by a subcontractor, and if such delay arises
          out of causes beyond the control of both the Contractor and
          subcontractor, and without the fault or negligence of any of them, the
          Contractor shall not be liable for liquidated damages for delays,
          unless the Equipment or Services to be furnished by the Contractor or
          Subcontractor were obtainable from other sources in sufficient time to
          permit the Contractor to meet the required Installation Date.

     E.   The Commonwealth shall have the option of billing the Contractor or
          deducting from any invoice an amount equal to the above as liquidated
          damages or waiting for the Contractor's certification so the
          Acceptance Testing can begin.

     F.   If the delay of installation of any Equipment is more than thirty (30)
          calendar days, then during that or the subsequent thirty (30) day
          period the Contractor may elect to install substitute Equipment,
          acceptable to the Commonwealth, of at least equal capabilities (or
          greater capabilities at the Contractor's option) and capable of
          performing the functions of such Equipment, as specified in the
          manufacturer's published specifications for the Equipment and the
          Commonwealth's required functions and features. If the Contractor does
          not elect to install substitute Equipment during either such period,
          then by written notice to the Contractor, the Commonwealth may
          terminate the right of the Contractor to install such original or such
          substitute Equipment, and may obtain other Equipment in place thereof.
          The Commonwealth is not liable for any packing, unpacking, drayage,
          rigging, shipping and installation charges for any of the Contractor's
          substitute Equipment.

     G.   If some, but not all, of the System or a Subsystem is Ready For Use by
          the required date, and the Commonwealth uses for operational purposes
          any such installed Subsystem, liquidated damages shall not accrue
          against the Subsystem used.

     H.   If the delays are caused by the Engineering and Quality Assurance
          Contractor, the Site

<PAGE>

          Development contractor or the Microwave contractor, the delay shall be
          handled in the same manner as a delay in Site availability and
          liquidated damages shall not apply.

A.14 NEED FOR EQUIPMENT DUE TO EMERGENCY

     A.   For a period of two (2) years after System Acceptance, the Contractor
          shall make reasonable efforts to assist the Commonwealth in procuring
          use of Equipment compatible with that used by the Commonwealth to meet
          emergencies such as, but not limited to, major breakdowns and
          unforeseen incidents.

     B.   The Commonwealth, at its option, may accept or reject the offer of use
          of emergency Equipment. If accepted, the charge for such use, if any,
          shall be by separate arrangement between the Commonwealth and the
          entity providing the emergency Equipment.

     C.   Contractor shall make available spare parts and service support for
          all equipment supplied under this procurement for a minimum of 10
          years from the date of execution of the contract. Contractor agrees to
          supply the Commonwealth with written notification of the
          discontinuance of production of any Contractor-manufactured hardware
          or equipment no later than 1 year prior to discontinuance.

A.15 ALTERATIONS AND INTERCONNECTIONS

     A.   The Commonwealth may make Alterations or install Interconnections to
          Sites, Subsystems, Equipment or Components at the Commonwealth's
          expense.

     B.   When such Alterations or Interconnections are made by other than the
          Contractor:

          i.   The Commonwealth shall be responsible for damage to the System
               caused by or resulting from such Alterations or Interconnections;

          ii.  The Contractor shall not be held responsible for any defects or
               malfunctions or non-conformance caused by or resulting from such
               Alterations or Attachments;

          iii. The Commonwealth shall pay the Contractor for any increase in the
               cost of effort related to maintenance service for the System,
               caused by or resulting from such Alterations or Interconnections;

          iv.  Such Alterations or Interconnections shall be removed and the
               Equipment restored to the prior configuration at the
               Commonwealth's expense upon return of the Equipment to the
               Contractor; and

          v.   There shall be no effect on the Contractor under this Contract as
               a result of such Alterations or Interconnections, whether for
               warranty, time of performance or other purposes.

A.16 TRAINING AND TECHNICAL SERVICES

     A.   The Contractor shall provide training as specified in Rider D. Any
          training or

<PAGE>

          additional Services over and above that referenced in Rider D shall be
          at the Contractor's then standard terms and charges.

     B.   The Contractor's technical personnel shall be available to assist the
          Commonwealth in development and implementation of the System, as
          specified in Riders B and D. Any technical Services over and above
          that referenced in Riders B and D will be made available to the
          Commonwealth at the Contractor's then standard terms and charges.

A.17 ASSIGNED PERSONNEL

     A.   The Contractor shall provide to the Commonwealth a summary of
          technical qualifications for each individual assigned to the
          Commonwealth at the Commonwealth's location in support of this
          contract. The Commonwealth must approve the selection of these
          personnel in advance of their assignment to this project.

     B.   Contractor agrees that key personnel, including management,
          engineering, and supervisory, assigned to the project shall remain
          assigned to the project unless terminated or due to unforeseen
          circumstances.

     C.   In the event of termination or unforeseen circumstances, substitutes
          for assigned personnel shall be approved in advance by the
          Commonwealth, shall have comparable levels of responsibility and
          authority, and shall have substantially equivalent experience and
          skill. Contractor agrees to make available for interview purposes any
          individuals proposed for this project, and agrees to supply the
          Commonwealth with resume, work history, or other requested
          documentation supporting the contractor's proposed assignment or
          substitution. The Commonwealth reserves the right to accept or reject
          any or all individuals recommended for project assignment.

A.18 SITE PREPARATION

     A.   The Contractor will notify the Commonwealth in writing as to the
          adequacy of the Commonwealth's planned layout of each Site for the
          Equipment within thirty (30) days after receipt of the Commonwealth's
          plans. The parties shall mutually agree upon any changes, if a planned
          layout is not adequate. If such agreement is not reached, Paragraph
          A.53 shall be applicable.

     B.   Any Contractor alterations or modifications in Site Preparation, which
          are attributable to incomplete or erroneous investigations,
          calculations, or engineering requirements provided by the Contractor
          and which involve additional expense to the Commonwealth, shall be
          made at the expense of the Contractor.

     C.   If any such alterations as specified in Paragraph C above, cause a
          delay in the installation, the provisions as specified in LIQUIDATED
          DAMAGES paragraph of this Contract will apply in accordance with the
          provision thereof.

     D.   If Commonwealth or federal environmental agencies provide the
          Contractor with guidelines or directives on site preparation, which
          are followed in good faith by the

<PAGE>

               Contractor, and it later proves to be erroneous or incomplete,
               the Commonwealth will pay the additional expense and no
               liquidated damages shall be applicable.

A.19 TRANSPORTATION OF EQUIPMENT

     A.   Shipment to the installation Sites shall be made at no expense to the
          Commonwealth.

     B.   Transportation charges for the shipment of empty packing cases shall
          be paid by the Contractor except when Equipment is moved from one
          Commonwealth location to another.

     C.   Relocation of Equipment for the Commonwealth's convenience shall be at
          the Commonwealth's expense. However, if relocation is due to the
          Contractor's improper initial location of Equipment, the Contractor
          shall be liable for relocation, packing and unpacking of Equipment
          without charge to the Commonwealth.

A.20 RISK OF LOSS

The Commonwealth shall be relieved from all risk of loss or damage to the
Equipment while it is at the Contractor's storage and service facilities, when
it is shipped to installation locations, and until the Commonwealth accepts the
System. However, Contractor shall not be responsible for loss or damage caused
by the Commonwealth, its Engineering and Quality Assurance Contractor, the
Microwave System contractor or the Trunked Radio System contractor.

A.21 LAWS AND REGULATIONS

     A.   The attention of Contractor is directed to the federal state and local
          laws, regulations, and ordinances in reference to labor, materials,
          equipment, specifications, proposals, contracts, bonds (bid,
          performance, and payment), environmental impacts, and all other
          matters pertaining to the relationship between the Commonwealth and
          Contractor. Contractor shall be aware of and shall at all times
          observe and comply with federal, state, and local laws, ordinances,
          and regulations, which in any manner affect the Contract or the work.
          Contractor shall be responsible for ascertaining the applicable laws,
          ordinances, rules, regulations, permit requirements, or other legal
          requirements governing the Contractor's activities hereunder.

     B.   Contractor shall indemnify, save and hold harmless the Commonwealth
          against any claim, judgement, fine, penalty, or other cost arising
          from the violation of such laws, ordinances, or regulations, whether
          committed by the Contractor, or the Contractor's agents, servants, or
          employees, or the Contractor's subcontractors, their agents, servants,
          or employees. In the event the Commonwealth becomes aware or receives
          notice of a violation, the Commonwealth shall provide prompt written
          notice of any matter covered by this Paragraph, and Contractor shall
          have the right to assume the defense thereof.

A.22 NON-DISCRIMINATION/SEXUAL HARASSMENT CLAUSE

During the term of the Contract, the Contractor agrees as follows:

<PAGE>

     A.   In the hiring of any employees for the manufacture of supplies,
          performance of work, or any other activity required under the Contract
          or any subcontract, the Contractor, subcontractor or any person acting
          on behalf of the Contractor or subcontractor shall not by reason of
          gender, race, creed, color, disability, national origin, ancestry or
          age discriminate against any citizen of the Commonwealth who is
          qualified and available to perform the work to which the employment
          relates.

     B.   Neither the Contractor nor any subcontractor nor any person on their
          behalf shall in any manner discriminate against or intimidate any
          employee involved in the manufacture of supplies, the performance of
          work or any other activity required under the Contract on account of
          gender, race, creed, color disability, national origin, ancestry or
          age.

     C.   Contractor and subcontractors shall establish and maintain a written
          sexual harassment policy and shall inform their employees of the
          policy.

     D.   The Contractor and each subcontractor shall furnish all necessary
          employment documents and records to and permit access to their books,
          records, and accounts by the contracting officer and the Department of
          General Services' Bureau of Contract Administration and Business
          Development for purposes of investigation to ascertain compliance with
          the provisions of the Nondiscrimination/Sexual Harassment Clause. If
          the Contractor or any subcontractor does not possess documents or
          records reflecting the necessary information request, it shall furnish
          such information on reporting forms supplied by the contracting
          officer of the Bureau of Contract Administration and Business
          Development.

     E.   The Contractor shall include the provisions of this
          Nondiscrimination/Sexual Harassment Clause in every subcontract so
          that such provision will be binding upon each subcontractor.

     F.   The Commonwealth may cancel or terminate the Contract and all money
          due or to become due under the Contract may be forfeited for a
          violation of the terms and conditions of this Nondiscrimination/Sexual
          Harassment Clause.

A.23 QUARTERLY REPORT - MBE, WBE, SERB

The Contractor must provide the Department of General Services, Bureau of
Contract Administration and Business Development, Room 502 North Office
Building, Harrisburg, Pennsylvania 17125, with quarterly reports that indicate
whether the Contractor utilized a Minority Business Enterprise, Women's Business
Enterprise, or Socially/Economically Restricted Business, Women's Business for
activities under this Contract during the quarter. The quarterly reports must
include a list of names and the amount paid to the Minority Business Enterprise,
Women's Business Enterprise, or Socially/Economically Restricted Business
utilized. The first such report shall be due on the 100th day after the starting
date of this Contract, and subsequent reports shall be due each 100th day after
the starting date of this Contract, and subsequent reports shall be due each
100th day thereafter. However, a report is not required if a

<PAGE>

Minority Business Enterprise, Women's Business Enterprise, or
Socially/Economically Restricted Business was not used during the reporting
period.

A.24 LICENSE AND PERMITS

Contractor shall procure at his own expense all licenses and permits necessary
to perform the work except for such permits as may be provided by the
Commonwealth as set forth elsewhere herein.

A.25 PRIME CONTRACTOR ROLE

     A.   The Contractor shall be prime contractor for the effort hereunder. The
          Contractor will be required to assume responsibility for all
          contractual activities offered in the Proposal whether or not the
          Contractor performs them. Further, the Commonwealth will consider the
          Contractor to be the sole point of contact with regard to contractual
          matters including payment of any and all charges resulting from this
          Contract.

     B.   Contractor shall employ a competent responsible representative who
          shall represent Contractor at Sites at all times during the execution
          of services in performance of this Contract. Contractor shall notify
          the Commonwealth in writing of the name of its representative(s), and
          of subsequent changes, for approval.

     C.   Contractor shall provide the proper tools and equipment, and shall
          secure the services of technical experts, and other employees
          necessary to the performance of the work. The employees of Contractor
          shall be competent and willing to perform satisfactorily the work
          required of them. A worker, subcontractor, or other agent who, in the
          opinion of the Commonwealth is intemperate, disorderly, disruptive, or
          who neglects or refuses to perform the work in a safe and competent
          manner shall, upon request of the Commonwealth, be promptly removed
          from the Site and shall be allowed to return to the Site only with the
          Commonwealth's consent upon Contractor's representation that the
          worker, subcontractor, or agent is willing and able to perform
          satisfactorily.

     D.   Assignment, delegation or subletting of this Contract or rights or
          duties hereunder by Contractor, in which the value of the contract
          exceeds $100,000, without the written consent of the Commonwealth
          shall be void. No consent is required for such identified contractors.
          Subject to the foregoing, this Contract shall bind and inure to the
          benefit of the parties and their successors and assigns.

     E.   The Commonwealth reserves the right to approve subcontractors for this
          project and to require the Contractor to replace subcontractors found
          to be unacceptable. The Contractor is totally responsible for
          adherence by the subcontractor(s) to all provisions of the Contract.

     F.   The Commonwealth acknowledges responsibility for integration of the
          System purchased under this Contract and other systems and equipment
          purchased through other related contracts. Contractor agrees to
          provide the Commonwealth with technical support, including engineering
          investigation and research if required, necessary to enable the
          Commonwealth to fully characterize the interface requirements

<PAGE>

          of Contractor's System as needed to complete system integration.

     G.   The Commonwealth reserves the right to delegate its responsibilities
          for technical review, implementation supervision, acceptance testing,
          or other non-fiduciary responsibilities under this Contract to the
          EQAC, to Commonwealth agencies, to the Commonwealth's partners, to
          other Commonwealth contractors, or to designated individuals as it
          deems appropriate. Contractor shall be notified of such delegation, if
          it occurs, by written notice as provided for in this Contract.

A.26 CONFLICTS OF INTEREST

     A.   No personnel of the Contractor or member of the governing body of any
          locality, or other public official or employee of any such locality in
          which, or relating to which, the work under this Contract is being
          carried out, and who exercises any functions or responsibilities in
          connection with the review or approval of the undertaking or carrying
          out of the work shall, prior to the completion of the work voluntarily
          acquire any personal interest, direct or indirect, which is
          incompatible, or in conflict with the discharge and fulfillment of
          such person's functions and responsibilities with respect to the
          implementation of such work.

     B.   Any person who acquires an incompatible or conflicting personal
          interest, prior to, on or after the effective date of this Contract,
          or who involuntarily acquires any such incompatible or conflicting
          personal interest, shall immediately disclose his or her interest to
          the Commonwealth in writing. Thereafter, such person shall not
          participate in any action affecting the work under this Contract,
          unless the Commonwealth shall determine that in the light of the
          personal interest disclosed, such person's participation in any such
          action would not be contrary to the public interest.

A.27 ACCOUNTING AND BOOKKEEPING REQUIREMENTS

<PAGE>

     A.   The Contractor shall keep all financial records in a manner consistent
          with generally accepted accounting principles. Documentation to
          support each action shall be filed in a manner allowing it to be
          readily located.

     B.   All disbursements made for the Contract shall be only for obligations
          incurred in the performance of this Contract and shall be supported by
          contracts, invoices, vouchers, and other data as appropriate to
          support such disbursements. All disbursements for the Contract shall
          be for obligations incurred only after the effective date of the
          Contract, unless specific authorization for prior disbursements has
          been given in writing by the Commonwealth.

     C.   During the period covered by the Contract, and until the expiration of
          three (3) years after final payment under the Contract, the Contractor
          agrees to provide the Commonwealth, its duly authorized
          representative, and any person, agency or instrumentality providing
          the Commonwealth with financial support to the work undertaken
          hereunder with access to and the right to examine any books,
          documents, papers, and records of the Contractor involving
          transactions related to such work.

A.28     SINGLE AUDIT ACT

In compliance with the Single Audit Act of 1984, the Contractor agrees to the
following:

     A.   This Contract is subject to audit by Federal and state agencies or
          their authorized representative in accordance with the auditing
          standards promulgated by the Comptroller General of the United States
          and specified in Standards for Audits of Governmental Organizations,
          Programs, Activities, and Functions (Yellow Book - 1981 Revisions).

     B.   The audit requirement of this Contract will be satisfied if a single
          audit is performed under the provisions of the Single Audit Act of
          1984, 341 U.S.C. 7501 et seq., and all rules and regulations
          promulgated pursuant to the Act.

     C.   The Commonwealth reserves the right for Federal and State agencies or
          their authorized representatives to perform additional audits of a
          financial/compliance, economy/efficiency or program results nature, if
          deemed necessary.

     D.   The Contractor further agrees to comply with requirements that may be
          issued by the State Agency upon receipt of additional guidance
          received from the Federal Government regarding the Single Audit Act of
          1984.

A.29 OWNERSHIP

The Contractor hereby retains, on an exclusive basis, all rights, title, and
interest in any computer software, systems design, source code, work papers, and
all other information, documents and materials delivered, prepared or created by
the Contractor for or in connection with the Contract with the Commonwealth.
Computer software, systems design, source code and all other information,
documents and materials prepared for or in connection with the Contract shall be
licensed by the Contractor to the Commonwealth for use of all of these items
pursuant to Rider

<PAGE>

H. Work papers pertaining to the tasks and reports shall be made available, upon
request, to the Commonwealth or its representative for review, inspection, and
if desired, reproduction. Such work papers shall be retained for at least three
(3) years subsequent to the final payment under the Contract.

A.30 CONFIDENTIALITY

The Parties acknowledge that some of the data they each may be exposed to in the
performance of this Contract is of a confidential nature. Except as otherwise
required by applicable law, the Parties agree to observe complete
confidentiality with respect to all aspects of any confidential information,
proprietary data or trade secrets and any parts thereof, belonging to the other
or other manufacturer, contractor or distributor that each one's personnel gain
access to under or in connection with this Contract. The restrictions herein
shall survive the termination or expiration of this Contract for any reason and
shall continue in full force and effect and shall be binding upon the Parties or
any party claiming an interest in this Contract on behalf of or under the rights
of the Parties. The Parties shall advise their agents, employees, successors,
assigns, and subcontractors that are engaged in performance hereunder of the
restrictions, present and continuing, set forth herein. Each Party shall defend
and incur its respective costs, including reasonable attorney fees, for actions
which arise as a result of noncompliance by such Party regarding the
restrictions herein.

A.31 PUBLICITY

Any use or reference to the RFQC and this Contract by the Contractor to
promote, solicit, or disseminate information regarding the scope of the
Contract is prohibited unless otherwise agreed to in writing by the
Commonwealth. The Commonwealth agrees to be used as a reference by the
Contractor; provided however, that Contractor hereby holds harmless and
indemnifies the Commonwealth from any claims or damages arising from such
reference information

A.32 NOTICES

A. Notices to be given under this Contract shall be formulated in writing and
sent to the respective Party as follows:

         FOR THE CONTRACTOR:

         ---------------

         ---------------

         ---------------

         ---------------

         ---------------

         FOR THE COMMONWEALTH:
         Governor's Office of Administration
         Radio Project Office
         Donald Appleby, Program Manager
         One Technology Park
         Harrisburg, PA  17110-2913

<PAGE>

     B.   A party shall be deemed to have given notice for purposes of this
          Contract upon deposit of the correspondence (a) in registered or
          certified U. S. mail, postage prepaid, (b) with a nationally
          recognized courier service that maintains verifications of actual
          delivery, (c) by facsimile, with a copy sent by first-class U.S. mail,
          or (d) by delivering the same in person.

     C.   Either party may change its notification address by giving the other
          party written notice of the change.

A.33 COMPLETENESS OF PROPOSAL, ESTIMATES, AND DRAWINGS

     A.   Contractor acknowledges and understands the extent to which the RFQC
          and Proposal, as accepted (including drawings, data, etc.), is
          complete and that no change in the Contract price(s) shall be allowed
          to the extent that the Proposal is not complete. The Proposal and
          drawings are specifying the quality of work required, its nature and
          position, and the method of construction and operation insofar as
          these are determinable in advance.

     B.   Contractor hereby agrees that it will make no claim for damages, for
          anticipated profits, or for losses because of differences between the
          quantities of the various items of work actually done or services and
          materials actually furnished, and the quantities indicated in the RFQC
          and Proposal.

     C.   The various parts of the Contract are intended to supplement but not
          necessarily duplicate each other. Any work exhibited in one part and
          not in another shall be performed as if it had been set forth in all
          parts, so that the work will be performed according to the Contract.

     D.   Compensation for all profit and loss, both anticipated and actual,
          shall be considered as fully made in the Contract price(s) contained
          in Rider C.

A.34 OTHER CONTRACTS

     A.   Contractor is advised that this Contract is a part of a larger
          project, and that related contracts may be let accordingly. Contractor
          shall afford other contractors and subcontractors a reasonable
          opportunity for the performance of their work, and shall properly
          coordinate and schedule its work with theirs.

     B.   If a part of Contractor's work depends upon the work of another
          contractor or subcontractors for proper performance and results,
          Contractor shall carefully review and promptly report to the
          Commonwealth in writing any defect or delay in the performance of such
          work that renders it unsuitable for Contractor's proper performance
          and results, or that Contractor believes excuse the full and timely
          performance by Contractor.

A.35 RIGHT OF ENTRY

<PAGE>

The Commonwealth reserves the right at any time to enter the property or
location on which the work is to be performed, by such agent or agents, as it
may elect, for the purpose of inspecting the work.

A.36 SAFETY REQUIREMENTS

     A.   All parts of this Contract shall be performed in strict accordance
          with the safety requirements of applicable codes and statues, federal,
          state and local requirements, and the best industry practice.
          Contractor is fully obligated to follow all safety procedures on
          behalf of its Site personnel, Equipment, and properties involved in
          this project, including Contractor's subcontractors, the
          Commonwealth's employees and visitors.

     B.   All work performed by the Contractor at above-ground elevations,
          including work on masts, poles, towers, monopoles, rooftops, chimneys,
          and similar installation sites and antenna support structures, shall
          comply with regulations established by OSHA and with the guidelines
          established by the National Association of Tower Erectors.

A.37 PROTECTION OF PROPERTY AND EQUIPMENT

<PAGE>

     A.   Contractor shall use its best efforts to protect the adjacent or
          adjoining properties and equipment from damage or loss from
          Contractor's operations or its subcontractors' operations. Contractor
          shall bear the costs of damage or loss caused by its operations or
          those of his subcontractors.

     B.   Existing underground installations such as water pipes, oil and gas
          pipelines, sewers, telephone lines, power lines, and buried structures
          in the vicinity of the Work are indicated on the drawings only to the
          extent such information has been made available to or discovered by an
          Architect, Engineer, or the Commonwealth in preparing the drawings.
          There is no guarantee as to the accuracy or completeness of such
          information, and the responsibility for accuracy and completeness is
          expressly disclaimed. Contractor shall be responsible for the location
          and protection of underground installations that are crossed or
          exposed by his design.

     C.   Contractor shall be solely responsible for accurately locating
          existing underground installations in advance of excavating or
          trenching, by contacting their owners and by having the owners locate
          and mark the location of the underground facilities placed within the
          Site. Repair of damage to underground installations for which the
          Contractor is legally responsible shall be paid by the Contractor.

     D.   Delays, additional Work, or extra cost to Contractor caused by
          existing underground installations shall not constitute a claim for
          extra Work, additional payment, damages, or extensions of time. In the
          event that it is determined that existing underground installations
          may cause to be incurred, additional costs, delays, damages, etc.,
          Contractor will notify the Commonwealth to arrange for the appropriate
          disposition. This disposition may include, but not be limited to:
          additional compensation, modification/extension of the Schedule,
          relocation of the applicable Work to another Site, etc.

A.38 HOLD HARMLESS CLAUSE ISSUE

The Contractor shall be responsible for and agrees to indemnify and hold
harmless the Commonwealth from damages to property or personal injuries
(including wrongful death) to any person(s) and from related losses, damages,
expenses, claims, demands, suits and actions arising in connection with the work
performed by the Contractor. The Commonwealth shall give prompt written notice
to Contractor upon Commonwealth becoming aware of or receiving notice of any
matter covered by this Paragraph and Contractor shall have the right to
participate in the defense thereof.

A.39 FORCE MAJEURE

     A.   The term Force Majeure as used herein shall mean any and all causes
          beyond the reasonable control and without any fault or negligence of
          the Party failing to perform, such as action of the elements,
          including floods, tornadoes, or hurricanes, acts of public authorities
          and/or regulatory agencies, including inability to obtain required
          permits or authorizations, acts of public enemy, insurrection, riots,
          strikes, labor and material shortages, fires, explosions, breakdowns
          of or damage to plant, equipment or

<PAGE>

          facilities, interruptions of transportation, embargoes, acts of
          military authorities, or other causes of a similar nature which wholly
          or partly prevent the performance of an obligation under this
          Contract.

     B.   Inclement weather including rain, snow, ice, or conditions resulting
          therefrom shall not be considered Force Majeure. However, such
          inclement weather may provide the basis for a requested extension of
          schedule at the discretion of the Commonwealth without being
          considered Force Majeure.

     C.   If because of Force Majeure, either Party hereto is delayed in the
          performance of an obligation(s) under this Contract (other than the
          obligation of a party for monetary payment in connection with the
          performance of this Contract), and if such Party shall promptly
          deliver to the other Party written notice of such Force Majeure, then
          such obligation of the Party giving notice shall be suspended, as of
          the date of the notice, to the extent made necessary by Force Majeure
          and during its continuance. However, the Party giving notice shall use
          its best efforts to eliminate or overcome Force Majeure in order to
          minimize any delay in performance. The Party claiming Force Majeure
          shall use all reasonable efforts to mitigate the effects of Force
          Majeure upon the performance of the Contract.

     D.   Each party shall bear the costs it encounters as a result of the Force
          Majeure delay and the required efforts to mitigate the effects of the
          Force Majeure.

A.40 EXTENSION OF TIME DUE TO FORCE MAJEURE

     A.   After the beginning of any delay due to Force Majeure, Contractor
          shall promptly notify the Commonwealth verbally and in writing of the
          circumstances, and describe the action being taken to mitigate the
          effects of the delay.

     B.   Upon cessation of the Force Majeure, Contractor shall notify the
          Commonwealth in writing of the extension of time required, the
          Commonwealth shall then ascertain the facts, the effect on the
          Contract schedule(s), and make a good faith determination of the
          extension of time required, if any, and so notify Contractor in
          writing of the delay in the Contract schedule.

     C.   At a minimum, each day of Force Majeure delay should provide for an
          equivalent delay in the Contract schedule.

A.41 DAMAGES FOR DELAYS

     A.   Contractor shall receive no compensation for delays or hindrances to
          the work, except when direct and unavoidable extra cost to the
          Contractor is caused by the failure of the Commonwealth to provide
          information or material, if any, which is to be furnished by the
          Commonwealth and except as otherwise provided in this Contract.

     B.   When such extra compensation is claimed, the Contractor shall present
          a written claim to the Project Manager. Disapproval by the
          Commonwealth shall be subject to review

<PAGE>

          under Paragraph A.53, Dispute Resolution Process.

     C.   If delay is caused by specific orders given by the Project Manager to
          stop work, or by the performance of extra work, or by the failure of
          the Commonwealth to provide material or necessary instructions for
          carrying on the work, then such delay will entitle the Contractor to
          an equivalent extension of time, its applications for which shall,
          however, be subject to the approval of the Commonwealth; and no such
          extension of time shall release the Contractor or the surety on its
          performance bond from all of Contractor's obligations hereunder which
          shall remain in full force until the discharge of the Contract.

     D.   Contractor hereby covenants and agrees that each subcontract shall
          contain the following clause:

               "Except where the Contractor is found to be at fault or
          contributorily negligent, Contractor shall not be liable to a
          subcontractor for any delay to a subcontractor's work resulting from
          any act, negligence or default of the Commonwealth, or by reason of
          fire of other casualty, or on account of riots, strikes or other
          combined action of the workers or others, or on account of any acts of
          God or any other cause beyond Contractor's control; or on account of
          any circumstances caused or contributed to by a subcontractor."

A.42 BACKGROUND CHECKS

Contractor understands that its employees, agents, and subcontractors may have
access to sensitive or confidential information or materials under the control
of the Commonwealth during this Contract. Contractor agrees to require its
employees, agents, and subcontractors, and their employees, to agree to execute
signed individual releases authorizing the Commonwealth to conduct
investigations into those employees' backgrounds, criminal records, driving
records, and other desired measures as a condition of approval for assignment to
work on this Contract. Contractor further agrees that assignment of individuals,
agents, or subcontractors to work on this Contract shall be contingent upon
completion of such investigations with results to the satisfaction of the
Commonwealth.

A.43 INTOXICANTS AND DRUGS

     A.   Contractor shall not permit the introduction or use of intoxicating
          liquors or illegal drugs or any other drugs or substances which impair
          or may reasonably be expected to impair the performance or safety
          practices of any worker on the Site or on any of the grounds occupied
          or controlled by Contractor. Contractor shall not permit any worker or
          any other person on the Site who is or appears to be under the
          influence of any of the above stated substances.

     B.   If Contractor has an established drug screening program for its
          employees, Contractor shall apply such program to the work performed
          on the Site of the Contract.

A.44 PERFORMANCE BOND

<PAGE>

Contractor shall cause its surety to issue and maintain in favor of the
Commonwealth a performance bond in form and substance as set forth in Rider G.

A.45 PATENT, TRADEMARK, AND COPYRIGHT INFRINGEMENT INDEMNITY

     A.   WARRANTY. Contractor warrants that all goods, services, processes, and
          intellectual property furnished through, or used to perform this
          Contract will not infringe any patent, trademark, trade secret or
          copyright, provided that these items are not designed by the
          Commonwealth without Contractor's assistance. Contractor shall obtain
          all required licenses for the Commonwealth to use all software and
          hardware. If the use of any good, service, process or intellectual
          property furnished or used under this Contract is adjudged infringing
          and its use enjoined, Contractor shall, at its own expense, procure
          for use by the Commonwealth the right to continue using it, or replace
          it with a non-infringing equivalent, or modify it so that it becomes
          non-infringing. Contractor shall defend and reimburse the Commonwealth
          for any losses, costs and expenses including attorney's fees in
          connection with the enforcement of this warranty.

     B.   INDEMNITY. Contractor shall defend at its own expense any suits or
          proceedings brought against by the Commonwealth based on a patent,
          trademark or copyright infringement claim pertaining to any goods,
          services, processes, or intellectual property furnished or used by
          Contractor under this Contract. Upon receipt of a notice of a claim,
          the Commonwealth shall promptly notify Contractor of such a claim and
          provide assistance and information at Contractor's expenses. The
          Commonwealth has the right of participation in the suit or
          proceedings, if necessary. Contractor shall pay all judgments,
          damages, royalties and costs awarded against the Commonwealth and
          shall reimburse the Commonwealth therefor. This indemnity shall not
          apply to items designed by the Commonwealth without the Contractor's
          assistance.

A.46 REQUIRED INSURANCE COVERAGE

     A.   Contractor agrees to furnish certificates of insurance coverage issued
          by companies qualified to do business in the Commonwealth and in form
          acceptable to Commonwealth evidencing the following coverage and terms
          as hereinafter stated:

          i.   Worker's compensation insurance for all of the Contractor's
               employees and those of any subcontractor engaged in work at the
               Site of the project in accordance with the Worker's Compensation
               Act of 1915 and any supplements or amendments thereof.

          ii.  Public liability and property damage insurance to protect the
               Commonwealth, the Contractor, and any and all subcontractors from
               claims for damages for personal injury (including bodily injury),
               sickness or disease, accidental death, and damage to property,
               including loss of use resulting from any property damage, which
               may arise from operations under this Contract, whether such
               operation be by the Contractor or by anyone directly or
               indirectly employed by either. The limits of such insurance shall
               be in an amount not less than $5,000,000 each person and

<PAGE>

               $5,000,000 each occurrence, personal injury and property damage
               combined. Such policies shall be occurrence rather than claims
               made policies and shall name the Commonwealth as an additional
               insured.

          iii. The insurance shall also cover the following: Contractor's own
               trucks and automobiles, trucks and automobiles hired by the
               Contractor, trucks and automobiles not owned or hired by the
               Contractor but used in connection with this project. The
               Automobile Liability Policy shall cover the use of automobiles
               and trucks on and off the Site of this Contract.

          iv.  No policy of insurance provided hereunder shall contain any
               endorsements or any other form or clause designed to limit and
               restrict any action by the Commonwealth as an additional insured
               against the insurance coverage in regard to the work performed
               for the Commonwealth.

          v.   The deductible portion of each type of coverage shall not exceed
               five percent (5%) of the coverage limit.

     B.   Prior to commencement of work under the Contract, the Contractor shall
          provide the Office of Administration, Director, Radio Project Office,
          with current certificates of insurance as set forth above. These
          certificates shall contain a provision that coverage afforded under
          the policies will not be canceled or changed until at least thirty
          (30) days prior written notice has been given to the Office of
          Administration, Radio Project Office.

A.47 SUSPENSION

     A.   The Commonwealth shall have the right at any time to suspend all or
          any part of the work upon written notice to the Contractor.
          Thereafter, the Commonwealth shall pay to Contractor the difference
          between the value of the work performed, and the sum of the payments
          made prior to the date of suspension. This additional payment, if any,
          shall be credited to payments due following resumption of the work.
          Further payments in accordance with the terms of payment shall cease
          during the period of suspension, and Contractor shall be compensated
          for the delay and related damages incurred by it. When directed by the
          Commonwealth to resume the suspended work, Contractor and the
          Commonwealth shall establish a revised Project Schedule and revised
          deliverable dates.

     B.   The Contract price shall be adjusted to reflect any costs or savings
          attributable to such suspension of the work and extension of the
          schedule, and the adjustment to the Contract price shall be based upon
          the revised completion dates. Contract payments in accordance with
          terms of payment shall resume based upon the revised completion dates
          and revised Contract price.

     C.   If the work or any portion thereof has been suspended in accordance
          with the foregoing paragraph, and if the Commonwealth does not give
          notice in writing to Contractor to resume the work within thirty (30)
          days, then Contractor may declare the

<PAGE>

          suspended work or the suspended portion thereof as terminated for
          convenience, and then the termination charges as specified in
          Paragraph A.48 shall be based only on the portion of the work that is
          so terminated.

A.48 TERMINATION/CANCELLATION

     A.   The rights of termination and cancellation shall take precedence over
          the other provisions of the Contract.

     B.   The Commonwealth has the right to terminate this Contract for any of
          the following reasons:

          i.   TERMINATION FOR CONVENIENCE: The Commonwealth may terminate this
               Contract for its convenience if the Commonwealth determines
               termination to be in its best interest. The Contractor shall be
               paid for work satisfactorily completed prior to the effective
               date of the termination as well as for work in process and its
               costs of termination, but in no event shall the Contractor be
               entitled to recover loss of profits.

          ii.  NON-APPROPRIATION: Contractor understands that the Commonwealth's
               funds for this Contract are contingent on the availability of
               lawful appropriations by the Pennsylvania Legislature and
               authorization by the Governor. If the Pennsylvania Legislature or
               the Governor fails at any time to continue funding for the
               Contract, the Commonwealth's obligations under the Contract are
               terminated as of the date that the funding expires without
               further obligations of the Commonwealth. The Commonwealth
               represents that as at the date of this Contract sufficient funds
               have been appropriated for the full payment under this Contract.
               In the event this Contract is terminated pursuant to this
               Paragraph, the Commonwealth shall not procure the same or a
               similar statewide radio system for the remainder of the current
               fiscal year, unless less than 182 calendar days remain in the
               current fiscal year, in which case the Commonwealth shall not
               procure the same or similar statewide radio system until the end
               of the following fiscal year.

          iii. TERMINATION FOR CAUSE: Unless otherwise specified herein, the
               Commonwealth reserves the right to terminate this Contract upon
               written notice for Contractor's nonperformance or inadequate
               performance if Contractor fails to commence remedial actions to
               cure the same within thirty (30) days after receipt of written
               notice thereof.

     C.   Upon termination or cancellation for any reason, Contractor shall
          deliver to the Commonwealth at the Site, in good operating condition,
          and normal wear and tear excepted, materials or equipment supplied to
          Contractor by the Commonwealth.

A.49 PERFORMANCE GUARANTEES

During the period of this contract, Contractor guarantees that the performance
of the materials furnished under the Contract will meet the requirements of the
Contract relating to design and

<PAGE>

performance when operated in accordance with generally accepted operating
practices of public safety.

A.50 TAXES

     A.   The Commonwealth and the Contractor understand and agree that the
          Contractor will not be responsible for paying or collecting
          Pennsylvania sales and use tax, or any similar tax, levy, duty or
          charge ("Sales Tax"), with respect to any services or property,
          whether tangible or intangible, provided to the Commonwealth by the
          Contractor under this Contract. In particular, it is agreed and
          acknowledged that all tangible property to be transferred to the
          Commonwealth under this Contract will either retain its character as
          tangible personal property or will be considered building machinery
          and equipment for purposes of the Sales Tax. The Commonwealth shall
          provide such exemption certificates as may be required by the
          Contractor from time to time to substantiate or qualify for any
          applicable exemptions from the Sales Tax.

     B.   The amounts payable to the Contractor under this Contract have been
          determined based upon the assumption that no county, municipality,
          city, town or other political subdivision of the Commonwealth will
          impose a mercantile license tax, business privilege tax or any other
          local tax, duty, levy or similar charge ("Local Tax") on the
          Contractor with respect to this Contract or the Contractor's
          activities hereunder.

     C.   If and to the extent that a Sales Tax is imposed on any services or
          property transferred by the Contractor to the Commonwealth under this
          Contract, or that any Local Tax is imposed on the Contractor with
          respect to this Contract or the Contractor's activities hereunder, the
          Commonwealth shall reimburse the Contractor, as an additional payment
          under the Contract, the amount of any such Sales Tax or Local Tax.

     D.   The Commonwealth is exempt from all excise taxes imposed by the
          Internal Revenue Service and has accordingly registered with the
          Internal Revenue Service to make tax free purchases under Registration
          No. 2374001-K. With the exception of purchases of the following items,
          no exception certificates are required and none will be issued: undyed
          diesel fuel, tires, trucks, gas-guzzler emergency vehicles, and sports
          fishing equipment. The Commonwealth is also exempt from the
          Pennsylvania Sales Tax. The Sales and Use Tax Regulations provide that
          exemption certificates are not required for sales made to government
          entities and none will be issued. Nothing in this paragraph is meant
          to exempt a construction contractor from payment of sales tax or use
          tax required to be paid with respect to its purchase or use of
          tangible personal property used or transferred in connection with the
          performance of its construction contract.

A.51 WARRANTY

     A.   Contractor shall provide Factory Warranty on all items purchased via
          this Contract as specified in Rider F. Factory Warranty is included in
          the price of Equipment as listed in Rider C. This is Contractor's
          standard twelve (12) month "Return to Factory" commercial product
          warranty, covering repair or replacement only of defective

<PAGE>

          products, with the warranty period starting the date the product is
          shipped from the factory. The factory is defined as the Factory
          Staging Facility for the Commonwealth and as the point of manufacture
          for other purchasers (i.e., counties and municipalities).

     B.   Regional Warranty is a separately priced and optional service provided
          by Contractor available only to the Commonwealth. Regional Warranty
          covers the Subsystems deployed to Sites within a Region and provides
          materials, labor and specific response/repair (frequency of
          response/repair times to be determined) as specified in Rider F. This
          Warranty, if purchased, will be utilized during the System
          Pre-Acceptance period on a Region by Region basis upon receipt by
          Contractor of written authorization from the Commonwealth, and can be
          ordered at any time before or after Regional Subsystem Acceptance.
          This coverage will be invoiced monthly, at a flat fee by Region as
          noted in Rider C.

     C.   System Warranty is a service provided by Contractor as part of the
          Commonwealth System acquisition, and is available to the Commonwealth
          only. System Warranty duration is a two (2) year period starting
          immediately after Final System Acceptance. Specific notice from the
          Commonwealth for commencement of the System Warranty is not required
          once notification is received that the Commonwealth has accepted the
          System. Coverage will provide materials, labor and specific
          response/repair (frequency of response/repair times to be determined)
          as in Rider F. System Warranty will apply to the entire System during
          the two (2) year period.

     D.   System Maintenance is an optional service offered by the Contractor to
          the Commonwealth only. System Maintenance includes the identical
          coverage as provided for in "System Warranty". The commencement date
          will follow the expiration of the two (2) year System Warranty and
          extend for either two (2) years or five (5) years (two distinct priced
          options provided). The frequency of response/repair times is to be
          determined at selection of options as specified in Rider F. The
          Commonwealth must provide written notification of its intent to
          exercise either the two (2) year or five (5) year System Maintenance
          option at least sixty (60) days prior to the expiration of the two (2)
          year System Warranty.

     E.   Factory Extended Warranty is a separately priced optional service
          offered by the Contractor to any purchaser of items from Rider C. This
          Extended Warranty provides extended and supplemental equipment
          maintenance services beyond or in augmentation of the Factory
          Warranty. Price and scope is as determined in Rider C. Options include
          on-site response, drive in/depot repairs, return to factory extension,
          etc.

     F.   Contractor shall respond to system and equipment malfunctions, while
          services included in Paragraphs B, C, and D above are in effect, by
          having a qualified technician arrive at the site within the times
          specified in Rider F. For minor failures as defined in Rider F, the
          contractor shall agree to pay to the Commonwealth as liquidated
          damages the sum of $200 for each and every hour of delay, for a
          maximum of 360 days per incident. For major failures as defined
          in Rider F, the contractor shall

<PAGE>

agree to pay to the Commonwealth as liquidated damages the sum
          of $300 for each and every hour of delay, for a maximum of 360 days
          per incident.

     G.   THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
          PURPOSE ARE HEREBY EXCLUDED.

A.52 CHANGES IN THE WORK

     A.   The Commonwealth may direct reasonable changes in the work called for
          in the Proposal by making alternations or additions to or deletions
          from the work, without invalidating the Contract and without relieving
          or releasing Contractor from any responsibility or guarantee given by
          it pursuant to the Contract. All changes in the work shall be
          performed under the terms, conditions, and specifications of the
          original Contract, and in all respects shall be in conformance with
          the requirements of the Contract, as though originally included
          therein.

     B.   A claim for an adjustment to the contract price or schedule for
          changes in the work shall be promptly brought to the Commonwealth's
          attention and agreed upon in advance of the change order authorizing
          the change in the work. Contractor shall be entitled to no claim for
          damages, other than for costs already incurred and for termination
          costs, and for anticipated profits or overhead on any portion of the
          Work that may be deleted by a change order. Agreed upon changes in the
          Contract price, task price, or schedule, if any, shall be stated on
          the change order.

     C.   Except in any emergency endangering life or property, changes in the
          Scope of Work shall be made only in accordance with a written change
          order originated by the Commonwealth stating the nature and extent of
          the change.

     D.   For any authorized change in the work, the contracting parties are
          restricted to the use of one of the following pricing methods to
          determine the amount to be added to or deducted from the Contract
          price for the change in work. The pricing method to be used shall be
          agreed upon and stated on the change order prior to Contractor's
          starting the change.

          i.   Method (1): By agreement upon unit prices, where applicable unit
               prices are not stipulated in the Contract, for the work to be
               done; or

          ii.  Method (2): By agreement upon a lump sum price for the work to be
               done; or

          iii. Method (3): By agreement that Contractor to be paid on a time and
               material basis at a fixed hourly rate by labor category plus
               materials at cost including a materials handling rate. If this
               method is agreed upon, Contractor shall maintain accurate,
               current, itemized records for such time as the Commonwealth may
               require for a correct accounting of hours expended by labor
               category and the cost of materials, together with all proper
               vouchers and supporting documents.

     E.   If the change in work results in a credit to the Commonwealth from
          Contractor or from a subcontractor, the amount credited to the
          Commonwealth shall be the total actual

<PAGE>

          cost (as defined above) of the change in work.

     F.   An itemized statement of actual cost for changes increasing the work
          or for net credit to the Commonwealth for changes decreasing the work,
          shall be rendered by Contractor no later than fifteen (15) calendar
          days after completion of the additional work, or after issuance of the
          change order if a decrease in work.

A.53 DISPUTE RESOLUTION PROCESS

     A.   In the event of a controversy or claim arising from the Contract, the
          Contractor must file a written notice of controversy or claim with the
          Contracting Officer for a determination.

     B.   Upon receipt of such a notice, the Contracting Officer shall
          investigate the notice and send his or her written determination to
          the Contractor.

     C.   The Contractor may request an administrative appeal of the Contracting
          Officer's determination within 60 days of issuance of the Contracting
          Officer's determination. The Deputy Secretary for Information
          Technology, Governor's Office of Administration, shall review the
          administrative appeal. The Deputy Secretary shall investigate the
          appeal and issue a written determination to the Contractor.

     D.   The decision of the Deputy Secretary shall be final, conclusive, and
          unreviewable in all respects unless the Contractor files a claim with
          the Commonwealth Board of Claims pursuant to Act of May 20, 1937, P.L.
          728, as amended (72 P.S. 4651-1).

     E.   Contractor may seek review of an adverse decision of the Commonwealth
          Board of Claims to the Commonwealth Court of Pennsylvania as provided
          by applicable law. Any disputes arising under this Contract, but
          outside the jurisdiction of the Commonwealth Board of Claims, shall be
          brought only in the courts of the Commonwealth of Pennsylvania or in
          the federal courts in the Middle District of Pennsylvania.

     F.   Pending a final resolution of a controversy or claim, including the
          final judicial resolution thereof, the Contractor shall proceed
          diligently with the performance of the Contract in a manner consistent
          with the interpretation of the Contracting Officer and the
          Commonwealth shall compensate the Contractor pursuant to the terms of
          the Contract.

A.54 OFFSET PROVISION FOR COMMONWEALTH CONTRACTS

The Contractor agrees that the Commonwealth may set off the amount of any state
tax liability or other debt of the Contractor or its subsidiaries that is owed
to the Commonwealth and not being contested on appeal against any payments due
the Contractor under this or any other contract with the Commonwealth.

A.55 CONTRACTOR RESPONSIBILITY PROGRAM

<PAGE>

     A.   As indicated in Management Directive 215.9 "Contractor Responsibility
          Program", the Commonwealth has established a system to monitor vendor
          performance. If Contractor has not performed as required by the
          Contract, the using agency will notify the Department of General
          Services. The information provided will be reviewed and if deemed to
          be appropriate, will be entered in the central Contractor
          Responsibility File. This information will be used by the Commonwealth
          to assist in determining if a vendor is responsible. If it is
          determined the Contractor is not responsible, they will be ineligible
          for contract awards.

     B.   Contractor certifies that it is not currently under suspension or
          debarment by the Commonwealth, any other state, or the federal
          government, and if the Contractor cannot so certify, then it agrees to
          submit along with the bid/proposal, a written explanation of why such
          certification cannot be made.

     C.   If Contractor enters into any subcontracts or employs under this
          Contract any subcontractors/individuals who are currently suspended or
          debarred by the Commonwealth or federal government or who become
          suspended or debarred by the Commonwealth or federal government during
          the term of this Contract or any extensions or renewals thereof, the
          Commonwealth shall have the right to require the Contractor to
          terminate such subcontracts or employment.

     D.   The Contractor agrees to reimburse the Commonwealth for the reasonable
          costs of investigation incurred by the Office of the Inspector General
          for investigations of the Contractor's compliance with the terms of
          this or any other agreement between the Contractor and the
          Commonwealth which results in the suspension or debarment of the
          Contractor. Such costs shall include, but not be limited to, salaries
          of investigators, including overtime; travel and lodging expenses; and
          expert witness and documentary fees. The Contractor shall not be
          responsible for investigative costs for investigations which do not
          result in the Contractor's suspension or debarment.

     E.   The Contractor may obtain the current list of suspended and debarred
          contractors by contacting the:

                  Department of General Services
                  Office of Chief Counsel
                  603 North Office Building
                  Harrisburg, PA  17125
                  Telephone No.:  (717) 783-6472
                  FAX No.: (717) 787-9138

A.56 AMERICANS WITH DISABILITIES ACT

During the term of this Contract, the Contractor agrees as follows:

     A.   Pursuant to federal regulations promulgated under the authority of The
          Americans With Disabilities Act, 28 C.F.R. 35.101 et seq., the
          Contractor understands and agrees that no individual with a disability
          shall, on the basis of the disability, be excluded from participation
          in the Contract or from activities provided for under this Contract.

<PAGE>

          As a condition of accepting and executing this Contract, the
          Contractor agrees to comply with the "General Prohibitions Against
          Discrimination," 28 C.F.R. 35.130, and all other regulations
          promulgated under Title II of The Americans With Disabilities Act,
          which are applicable to the benefits, services, programs, and
          activities provided by the Commonwealth through contracts with outside
          contractors.

     B.   The Contractor shall be responsible for and agrees to indemnify and
          hold harmless the Commonwealth from losses, damages, expenses, claims,
          demands, suits, and actions brought by any party against the
          Commonwealth as a result of the Contractor's failure to comply with
          the provisions of paragraph A above. Upon receipt of notice of a
          claim, the Commonwealth shall provide prompt written notice to
          Contractor of any matter covered by this Paragraph and Contractor
          shall have the right to participate in the defense thereof.

A.57 CONTRACTOR INTEGRITY PROVISIONS

     A.   Definitions:

          i.   CONFIDENTIAL INFORMATION means information that is not public
               knowledge, or available to the public on request, disclosure of
               which would give an unfair, unethical, or illegal advantage of
               another desiring to contract with the Commonwealth.

          ii.  CONSENT means written permission signed by a duly authorized
               officer or employee of the Commonwealth, provided that where the
               material facts have been disclosed, in writing, by
               prequalification, bid, proposal, or contractual terms, the
               Commonwealth shall be deemed to have consented by virtue of
               execution of this Contract.

          iii. CONTRACTOR means the individual or entity that has entered into
               this Contract with the Commonwealth, including directors,
               officer, partners, managers, key employees and owners of more
               than five percent (5%) interest.

          iv.  FINANCIAL INTEREST means:

               a.   ownership of more than five percent (5%) interest in any
                    business; or

               b.   holding a position as an officer, director, trustee,
                    partner, employee, or the like, or holding any position of
                    management.

<PAGE>

          v.   GRATUITY means any payment of more than normal monetary value in
               the form of cash, travel, entertainment, gifts, meals, lodging,
               loans, subscriptions, advances, deposits of money, services,
               employment, or contracts of any kind.

     B.   The Contractor shall maintain the highest standards of integrity in
          the performance of this Contract and shall take no action in violation
          of state or federal laws, regulations, or other requirements that
          govern contracting with the Commonwealth.

     C.   The Contractor shall not disclose to others any confidential
          information gained by virtue of this Contract.

     D.   The Contractor shall not, in connection with this or any other
          agreement with the Commonwealth, directly or indirectly, offer,
          confer, or agree to confer any pecuniary benefit on anyone as
          consideration for the decision, opinion, recommendation, vote, other
          exercise of discretion, or violation of a known legal duty by any
          officer or employee of the Commonwealth.

     E.   The Contractor shall not, in connection with this or any other
          contract with the Commonwealth, directly or indirectly, offer, give or
          agree or promise to give anyone any gratuity for the benefit of at the
          direction or request of any office or employee of the Commonwealth.

     F.   Except with the consent of the Commonwealth, neither the Contractor
          nor anyone in privity with him or her shall accept or agree to accept
          from, or give or agree to give to, any person, any gratuity from any
          person in connection with the performance of work under this Contract
          except as provided herein.

     G.   Except with the consent of the Commonwealth, the Contractor shall not
          have a financial interest in any other contractor, subcontractor, or
          supplier providing services, labor or material on this project.

     H.   The Contractor, upon being informed that any violation of these
          provisions has occurred or may occur, shall immediately notify the
          Commonwealth in writing.

     I.   The Contractor, by execution of the Contract and by the submission of
          any bills or invoices for payment pursuant thereto, certifies and
          represents that he or she has not violated any of these provisions.

     J.   The Contractor, upon the inquiry or request of the Inspector General
          of the Commonwealth or any of that official's agents or
          representatives, shall provide, or if appropriate, make promptly
          available for inspection or copying, any information of any type or
          form deemed relevant by the Inspector General to the Contractor's
          integrity or responsibility, as those terms are defined by the
          Commonwealth's statutes, regulations, or management directives. Such
          information may include, but shall not be limited to, the Contractor's
          business or financial records, documents or files of any type or form
          which refer to or concern this Contract. Such information shall be
          retained by the Contractor for a period of three years beyond the
          termination of this Contract unless otherwise provided by law.

<PAGE>

     K.   For violation of any of the above provisions, the Commonwealth may
          terminate this and any other contract with the Contractor, claim
          liquidated damages in an amount equal to the value of anything
          received in breach of these provisions, claim damages for all expenses
          incurred in obtaining another contractor to complete performance
          hereunder, and debar and suspend the Contractor from doing business
          with the Commonwealth. These rights and remedies are cumulative, and
          the use or nonuse of any one shall not preclude the use of all or any
          other. These rights and remedies are in addition to those the
          Commonwealth may have under law, statute, regulation, or otherwise.

A.58 CAPTIONS, NUMBERING AND LETTERING

The captions to sections and the numbering or lettering of sections in this
Contract are for convenience only and shall not be considered in construing the
intent of the parties.

A.59 CONSTRUCTION OF TERMS, CHOICE OF LAW

The terms of this Contract have been arrived at after mutual negotiation and,
therefore, it is the intent of the parties that its terms not be construed
against either of the Parties by reason of the fact that the Contract Documents
were prepared by one of the Parties. This Contract shall be deemed a contract
made in the Commonwealth for all purposes and shall be governed by and construed
according to the laws of the Commonwealth of Pennsylvania.

A.60 YEAR 2000 COMPLIANCE

The Contractor presents and warrants that each hardware, software and firmware
product delivered (or service performed) under the Contract, including
enhancements, shall be able to accurately process, provide and/or receive
date/time date (including, but not limited to, calculating, comparing and
sequencing) from, into and between the 20th and 21st centuries and the year 1999
and 2000, including leap year calculations, when used in accordance with the
Documentation provided by the Contractor, provided that all listed or unlisted
products (e.g. hardware, software, firmware, etc.) used in combination with such
product properly exchange date/time date with it.

No hardware, software, firmware or service provided under the Contract shall
change the status of hardware, software and firmware product not supplied by
Contractor which is Year 2000 compliant from Year 2000 compliant to Year 2000
noncompliant. The Contractor must notify the Commonwealth of any Year 2000
noncompliant hardware, software and firmware product located by the Contractor
during the course of performance of the Contract, design a plan of remediation
to create Year 2000 compliance and provide an estimate of the cost, if any, to
the Commonwealth to achieve Year 2000 compliance.

The Contractor shall not deliver any third-party hardware, software, firmware or
service to the Commonwealth which has not been represented and warranted in
writing by the third-party manufacturer to be Year 2000 compliant, as described
above. The Contractor shall pass through the third-party representation and
warranty from the third-party manufacturer to the Commonwealth.

<PAGE>

Any modifications or changes made by the Commonwealth or any of its third
parties to any hardware, software, or firmware provided under the Contract that
alters Year 2000 compliance shall void the Year 2000 warranty of the product.

This Year 2000 compliance representation and warranty shall be in effect until
the later of December 31, 2002 or the expiration of the Contractor's warranty.
In any event this representation and warranty shall survive termination of the
Contract and shall run until December 21, 2002. In no event will the acceptance
by the Commonwealth of any hardware, software or firmware product or service
delivered to the Commonwealth, by or though the Contractor, or any payment by
the Commonwealth to the Contractor under the Contract limit the effectiveness or
survival of this Year 2000 compliance representation and warranty.

A.61 RELATIONSHIP OF THE PARTIES

The status of the Contractor under this Contract will be that of an independent
contractor. No provision of this Contract will be interpreted to make the
parties to this Contract a partnership, principal-agent, employer-employee, or
trustee or beneficiary of any type.

A.62 WAIVERS

No delay, waiver, omission, or forbearance on the part of the Commonwealth to
exercise any right, option, duty, or power arising from the breach or default by
Contractor or a subcontractor of any of the terms, provision, or covenants
contained herein will constitute a waiver by the Commonwealth thereof to enforce
such right, option, or power as to any subsequent breach or default by
Contractor or a subcontractor.

A.63 PARTIAL INVALIDITY

Any provision of this Contract prohibited by law or by court decree in any
locality or state shall be suspended to the extent of such prohibition without
invalidating or affecting the remaining provisions of this Contract.

A.64 LIMITATION OF LIABILITY

Except (i) under Paragraph A.45 entitled Patent, Trademark and Copyright
Infringement Indemnity and (ii) with respect to personal injury and property
damage, in no event shall Contractor's liability hereunder, whether for breach
of warranty or contract, tort (including negligence) or otherwise, exceed an
amount equal to the aggregate value of RPRs issued under this Contract at the
time the Commonwealth first became aware of the occurrence of the event
allegedly giving rise to such liability. Such amount shall be reduced by any
monies paid to the Commonwealth pursuant to the Liquidated Damages clause to the
extent that such liability is attributable to Contractor caused delays. Any work
or services provided by the Performance Bond shall be taken into consideration
as mitigating any damage to the Commonwealth. In no event shall Contractor of
Contractor's suppliers or licensors have liability to the Commonwealth in excess
of $500,000 for consequential, indirect, incidental, or special damages
including but not limited to loss of revenue.

A.65 ELIGIBLE PURCHASES

<PAGE>

     A.   The contractor's prices for all equipment included in Rider C shall be
          included in State Contract 5820-06. The Commonwealth of Pennsylvania,
          Department of General Services administers state Contract 5820-06 via
          the Bureau of Purchases. Contractor agrees to allow state agencies and
          other eligible entities to purchase all equipment, services, and
          subsystems at the prices listed in Rider C except those items
          specifically excluded.

     B.   Contractor's pricing for State Contract 5820-06 shall remain fixed
          during the duration of this contract. The contractor shall participate
          in State Contract 5820-06 with the equipment listed in Rider C for a
          minimum of ten (10) years. Pricing adjustments to State Contract
          5820-06 shall only be permitted upon the Commonwealth's issuance of a
          new State Contract 5820-06. Pricing of all equipment in Rider C may
          not be increased in percentage more than the percentage increase to
          contractor's similar equipment included in newly adjusted GSA
          Contracts.

     C.   Contractor shall allow using agencies and other eligible Commonwealth
          entities to issue field purchase orders directly to the contractor for
          any equipment and subsystems that are covered by this Contract and
          included in State Contract 5820-06. Political subdivisions,
          commissions or authorities created by a political subdivision, private
          colleges or universities, GPU Energy, and other eligible entities are
          permitted to participate in or purchase from Contract 5820-06.

     D.   Quantities of equipment orders placed under State Contract 5820-06 are
          estimated only and may be increased or decreased in accordance with
          the actual requirements of the Commonwealth and associated entities.
          The Commonwealth shall only purchase the supplies, equipment, and
          materials in such quantities that represent the actual requirements of
          the Commonwealth.
<PAGE>

                           Rider B - Statement of Work
--------------------------------------------------------------------------------

                                     [LOGO]

                             ROHN CONSTRUCTION, INC.

                                     RIDER B

                                STATEMENT OF WORK

                                AND DELIVERABLES

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                           Rider B - Statement of Work
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<TABLE>
<CAPTION>

                                                                               RIDER B - TABLE OF CONTENTS
                                                                               ---------------------------

<S>                                                                                                     <C>
B-1      PROGRAM MANAGEMENT..............................................................................5

      PROJECT MANAGEMENT.................................................................................5
      ENGINEERING........................................................................................6
      SITE DEVELOPMENT MANAGEMENT........................................................................6

B-2      DELIVERABLES....................................................................................8

      PROGRAM DOCUMENTATION..............................................................................8
      B-2.1.1    PROGRAM IMPLEMENTATION PLAN (PIP).......................................................8
      B-2.1.2    PROGRAM SCHEDULE........................................................................8
      B-2.1.3    REQUEST FOR DESIGN (RFD) - SITE.........................................................9
      B-2.1.4    REQUEST FOR DESIGN (RFD) -REGION........................................................9
      B-2.1.5    PRELIMINARY SITE PLAN (PSP).............................................................9
      B-2.1.6    SITE DESIGN DOCUMENT (SDD).............................................................10
      B-2.1.7    SITE PRODUCTION RELEASE (SPR)..........................................................10
      B-2.1.8    SITE DEPLOYMENT ORDER (SDO)............................................................10
      B-2.1.9    INTERFACE SPECIFICATIONS...............................................................11
      B-2.1.10   DETAILED EQUIPMENT LIST................................................................11
      B-2.1.11   DETAILED DESIGN DOCUMENT (DDD).........................................................11
      B-2.1.12   QUALITY STANDARDS MANUAL...............................................................12
      B-2.1.13   SITE DOCUMENTATION PACKAGE.............................................................13
      B-2.1.14   TRAINING MANUALS.......................................................................13
      B-2.1.15   MONTHLY PROJECT REPORT.................................................................13
      B-2.1.16   MBE, WBE, SERB QUARTERLY REPORT........................................................13
      PROGRAM REVIEWS...................................................................................13
      B-2.2.1    MONTHLY PROGRAM REVIEWS................................................................13
      B-2.2.2    CONTRACT IMPLEMENTATION REVIEW (CIR)...................................................14
      B-2.2.3    PRELIMINARY DESIGN REVIEW (PDR)........................................................14
      B-2.2.4    CRITICAL DESIGN REVIEW (CDR)...........................................................14
      B-2.2.5    REGIONAL DESIGN REVIEWS (RDR)..........................................................14
      B-2.2.6    TECHNICAL INTERFACE COMMITTEE REVIEWS..................................................15
      B-2.2.7    SITE-READY VERIFICATION REVIEW.........................................................15
      B-2.2.8    SITE DOCUMENTATION REVIEW..............................................................15
      B-2.2.9    FINAL CONTRACT CLOSE-OUT REVIEW........................................................15

B-3      SHELTERS.......................................................................................16

      SHELTER DESIGN....................................................................................16
      B-3.1.1    REQUIREMENTS...........................................................................16
      B-3.1.2    VARIABLE REQUIREMENTS..................................................................17
      B-3.1.3    OPTIONAL REQUIREMENTS..................................................................17
      SHELTER STANDARDS.................................................................................17
      B-3.2.1    BUILDING CODES.........................................................................17
      B-3.2.2    ELECTRICAL CODES.......................................................................18
      SHELTER PERFORMANCE...............................................................................18
      B-3.3.1    SHELTER EMERGENCY GENERATOR ROOM.......................................................18
      B-3.3.2    SHELTER DIMENSIONS.....................................................................18
      SHELTER CONFIGURATIONS............................................................................18
      B-3.4.1    SHELTER ACCEPTANCE.....................................................................19
      B-3.4.2    SHELTER DELIVERY.......................................................................19

</TABLE>

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                          Rider B - Statement of Work
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<TABLE>

<S>                                                                                                    <C>
      SHELTER SUBMITTALS................................................................................19
      B-3.5.1    ENGINEERING DRAWINGS...................................................................19
      B-3.5.2    ELECTRICAL DESIGN DRAWINGS.............................................................19
      B-3.5.3    FOUNDATION DESIGN DRAWINGS.............................................................20
      SHELTER INSTALLATION..............................................................................20
      B-3.6.1    INSTALLATION REQUIREMENTS..............................................................20
      B-3.6.2    SHELTER INSTALLATION AT OPERATIONAL SITES..............................................21
      CONTRACTOR RESPONSIBILITIES.......................................................................21
      B-3.7.1    SHELTER SUBSYSTEM TO GENERATOR SUBSYSTEM VENDOR INTERFACE..............................21
      B-3.7.2    SHELTER SUBSYSTEM TO TOWER SUBSYSTEM VENDOR INTERFACE..................................23
      B-3.7.3    SHELTER SUBSYSTEM VENDOR TO MICROWAVE SYSTEM CONTRACTOR INTERFACE......................23
      B-3.7.4    SHELTER SUBSYSTEM VENDOR TO RADIO SYSTEM CONTRACTOR INTERFACE..........................24
      B-3.7.5    ADDITIONAL SHELTER SUBSYSTEM VENDOR RESPONSIBILITIES...................................24

B-4      EMERGENCY GENERATOR............................................................................26

      EMERGENCY GENERATOR DESIGN........................................................................26
      EMERGENCY GENERATOR PERFORMANCE...................................................................26
      EMERGENCY GENERATOR CONFIGURATIONS................................................................26
      EMERGENCY GENERATOR SHIPPING AND DELIVERY PROCESS.................................................27
      B-4.4.1    EMERGENCY GENERATOR FINAL SHIPPING DESTINATION.........................................27
      EMERGENCY GENERATOR SUBMITTALS....................................................................27
      B-4.5.1    ENGINEERING DRAWINGS...................................................................28
      GENERATOR INSTALLATION............................................................................28
      GENERATOR WARRANTY................................................................................28
      CONTRACTOR RESPONSIBILITIES.......................................................................28
      B-4.8.1    SHELTER SUBSYSTEM......................................................................28
      B-4.8.2    TOWER SUBSYSTEM........................................................................30
      B-4.8.3    MICROWAVE SUBSYSTEM....................................................................31
      B-4.8.4    RADIO SUBSYSTEM........................................................................31
      B-4.8.5    CIVIL CONTRACTOR.......................................................................31
      B-4.8.6    ADDITIONAL GENERATOR SUBSYSTEM VENDOR RESPONSIBILITIES.................................32

B-5      TOWERS.........................................................................................33

      TOWER DESIGN......................................................................................33
      TOWER PERFORMANCE.................................................................................33
      TOWER CONFIGURATION...............................................................................34
      TOWER SUBMITTALS..................................................................................34
      TOWER SHIPPING AND DELIVERY.......................................................................35
      TOWER INSTALLATION................................................................................36
      TOWER WARRANTY AND MAINTENANCE....................................................................37
      CONTRACTOR RESPONSIBILITIES.......................................................................37
      B-5.8.1    SHELTER SUBSYSTEM......................................................................38
      B-5.8.2    GENERATOR SUBSYSTEM....................................................................38
      B-5.8.3    MICROWAVE SUBSYSTEM....................................................................38
      B-5.8.4    RADIO SUBSYSTEM........................................................................38
      B-5.8.5    CIVIL CONTRACTOR.......................................................................38
      B-5.8.6    TOWER SUBSYSTEM........................................................................39

B-6      SITE WORK......................................................................................40

      SITE WORK REQUIREMENTS AND SPECIFICATIONS.........................................................40
      GENERAL CONSTRUCTION REQUIREMENTS.................................................................40
      SITE WORK DEFINITIONS.............................................................................40
      B-6.3.1    SITE WORK SUBMITTALS...................................................................41

B-7      CIVIL ENGINEERING..............................................................................42

</TABLE>

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                          Rider B - Statement of Work
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<TABLE>

<S>                                                                                                     <C>
      B-7.1.1    PROFESSIONAL ENGINEERING CERTIFICATION.................................................42
      B-7.1.2    TOWER DRAWINGS.........................................................................42
      B-7.1.3    KEY TOWER ERECTION DRAWINGS............................................................43
      B-7.1.4    SECONDARY TOWER DRAWINGS...............................................................43
      B-7.1.5    DRAWING PACKAGES.......................................................................43

B-8      ACCEPTANCE TESTING.............................................................................44

      SUBSYSTEM ACCEPTANCE TESTING......................................................................44
      B-8.1.1    EQUIPMENT SHELTER SUBSYSTEM ACCEPTANCE TESTING.........................................44
      B-8.1.2    EMERGENCY GENERATOR SUBSYSTEM ACCEPTANCE TESTING.......................................44
      B-8.1.3    TOWER SUBSYSTEM ACCEPTANCE TESTING.....................................................44
      B-8.1.4    SITE WORK SUBSYSTEM ACCEPTANCE TESTING.................................................44
      SUBSYSTEM INTEROPERABILITY ACCEPTANCE TESTING.....................................................44

B-9      PROJECT LOGISTICS AND SUPPORT..................................................................45

      INSTALLATION......................................................................................45
      B-9.1.1    INSTALLATION DOCUMENTATION.............................................................45
      B-9.1.2    INSTALLATION INSPECTIONS...............................................................46
      SHIPPING..........................................................................................46
      TRAINING..........................................................................................46
      WARRANTY / MAINTENANCE............................................................................46
      SPARES............................................................................................46

</TABLE>

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                          Rider B - Statement of Work
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B-1      PROGRAM MANAGEMENT

The Statement of Work is described in the following categories as outlined in
this, and the following, Work Breakdown Structure (WBS) sections.

PROJECT MANAGEMENT

This WBS collects costs and efforts associated with the Contractor's Project
Management activities for the preparation, administration, implementation,
inspection, and acceptance of the Site Development System or Subsystems.

The Contractor shall provide shelters, generators, towers, and fuel tanks to
include shipping, delivery, unloading, installation, tools, test equipment,
spares, modification, warranty, maintenance and/or removal of commodities as
detailed in the Site Development RFP. The Contractor shall also provide
foundations, ramps, grounding systems, fencing, clearing, grading, gravel,
spoils removal, excavation, backfill, and site development design and
engineering services to insure proper installation and maintenance of the site
infrastructure and equipment supplied by the Contractor. The contract Start Date
is the calendar date when all parties sign the completed contract. The baseline
program schedule is based upon a standard Monday through Friday, 8 AM - 5 PM
(Eastern U.S. Time Zone) workweek excluding Contractor holidays as follows.

    CONTRACTOR HOLIDAYS:

    -        November 25, 1999            Thanksgiving Day Holiday

    -        November 26, 1999            Thanksgiving Shutdown

    -        December 24, 1999            Christmas Eve Shutdown

    -        December 31, 1999            News Years Eve Shutdown

    -        April 21 , 2000              Good Friday

    -        May 29, 2000                 Memorial Day Holiday

    -        July 3, 2000                 Independence Day Shutdown

    -        July 4, 2000                 Independence Day Holiday

    -        September 4, 2000            Labor Day Holiday

    -        November 23, 2000            Thanksgiving Holiday

    -        November 24, 2000            Thanksgiving Shutdown

    -        December 25, 2000            Christmas Holiday

    -        December 26, 2000            Christmas Holiday Shutdown

    -        January 1, 2001              New Years Day Holiday

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                          Rider B - Statement of Work
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The Contractor shall provide the necessary level of Program Management, Systems
Engineering, Product Engineering, Manufacturing, Assembly, Test, Field
Installation, System Integration, Quality Verification, Acceptance Testing,
System Maintenance and Product Documentation, Training and other services as
outlined in the Site Development Request For Proposal, RFP # 1998-SD-1, dated
December 4, 1998 with Addenda.

ENGINEERING

This WBS collects costs and efforts associated with Engineering activities for
the preparation, administration, implementation, inspection, and acceptance of
the System or Subsystems.

The design baseline will be presented to the Commonwealth through Preliminary
and Critical Design Reviews as outlined in this Work Breakdown Structure (WBS).
Detailed Regional Design baselines shall be established by a Regional Design
Review (RDR), for each region.

The Contractor shall simultaneously develop multiple sites in accordance with
and in response to issuance of Commonwealth Site Deployment Order(s) (SDO).

All site equipment provided and installation methods used by the Contractor
shall comply with all current local, state and federal codes for installation
and operation of electrical and non-electrical equipment. Site preparation and
installations will be in accordance with the Contractor's Quality Standards
Manual (QSM). The Contractor shall ensure that sufficient Professional Engineers
(PE), licensed in Pennsylvania, are available to allow the timely preparation
and delivery of sealed drawings or drawing packages required for site
development.

SITE DEVELOPMENT MANAGEMENT

The Contractor's site superintendent shall monitor and coordinate the scheduling
of all on-site activities for which the Contractor is responsible, and shall
ensure compliance with all applicable specifications, drawings, and quality
standards. The Contractor's on-site site superintendent shall be responsible for
the day to day management and coordination of all phases of site work, tower
erection, shelter and generator installations. The Contractor's site
superintendents shall report the status of all site development activity under
their supervision, directly to the Contractor's Project Superintendent located
in the Harrisburg, Pennsylvania area. This status shall be submitted, at a
minimum, on a weekly basis through the Contractor's Project Superintendent to
the Commonwealth Radio Project Office, using the Primavera suite of program
management tools, Expedition and SureTrak.

The contractor shall provide a complete and functional site including all
equipment or parts required, but not specifically mentioned herein, without any
claim for additional payment. It shall be understood that the final contract and
agreement requires the

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                          Rider B - Statement of Work
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construction, services and installation of a completely operational tower,
shelter, emergency generator system and site development work that meets the
standards and requirements of the RFP.

It shall be the responsibility of the contractor to provide a turnkey
installation of the provided equipment. Optimization, trouble shooting, and
adjustment of each subsystem shall be the contractors responsibility. This
includes any changes and/or additions in order to meet performance criteria. Any
additional equipment required after the contract is awarded, to meet the system
performance criteria of the defined standards and/or specifications in the RFP
or defined herein shall be at the sole expense of the contractor, unless the
Commonwealth issues a change order.

Towers, shelters, generators, microwave, and radio equipment will be implemented
in an orderly manner and in full consideration to other contractors and their
responsibilities.

Any questions regarding lines of demarcation, system integration, or equipment
interface issues, between contractors' systems or subsystems not specifically
addressed in the RFP, the Proposal, or the Contract shall be addressed via the
Technical Interface Committee. The Technical Interface Committee shall consist
of a representative from each of the Contractors on the Statewide Voice and Data
System Project, the Commonwealth's Radio Project Office and their Affiliates.
The Technical Interface Committee shall address these issues on a discussion
basis building to a consensus. Electronic Data Exchange, Telephone Conference
Calls and Video Teleconferencing shall be used to the greatest extent possible
to discuss and resolve these issues. The outcome of this process will be a
recommended solution presented to the Contractors' Project Managers for their
concurrence and the Commonwealth's Project Director's approval.

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                          Rider B - Statement of Work
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B-2      DELIVERABLES

Unless otherwise noted, initial delivery of all draft and final program
documentation shall be accomplished electronically via e-mail or File Transfer
Protocol (FTP) to the Radio Project Office central e-mail address:
radio@state.pa.us. Following the electronic submittal, final versions of all
program documentation shall be delivered to the Radio Project Office in six (6)
hardcopies, accompanied by two electronic softcopies, each on a single 3.5"
floppy diskette, or if too large to fit on a 3.5" disk, on a CD-ROM disk.

All drawings and drawings sets shall be delivered in two sizes 8 1/2" by 14" and
ANSI D (24" x 36") size. The quantity of each size shall be at a 2:1 ratio to
meet the total required quantity. Version control, tracking, submission, review,
and approval of all deliverables, submittals, drawings, change requests,
contract documents, schedules, and invoices shall be accomplished using the
Primavera suite of program management tools including, but not limited to,
Expedition and SureTrak.

PROGRAM DOCUMENTATION

The program documentation described in the following sections shall be delivered
to the Commonwealth Radio Project Office, One Technology Park Room 190,
Harrisburg, PA 17110-2913.

All program documentation shall be supplied in accordance with the following
list and timeframes as referenced below. All references to internal and external
document sections shall include paragraph and/or section number, not by page
number alone.

B-2.1.1 PROGRAM IMPLEMENTATION PLAN (PIP)

The Program Implementation Plan (PIP) establishes the baseline from which the
program is to be executed. The PIP includes a program overview, master program
schedule, management organization, and a description of the Contractor's cost
and schedule control systems.

B-2.1.2 PROGRAM SCHEDULE

The Program Schedule WBS element collects the effort associated with the
planning and management of the Contractor program schedule. Administration and
management of tasks on the schedule is the responsibility of the Contractor
Program Manager. Separate Regional and Site Schedules will be provided weekly to
the Commonwealth of Pennsylvania, Radio Program Office in latest commercially
available version of Primavera SureTrak format. The Contractor will provide the
Commonwealth an Integrated Baseline Program Schedule 30 days after the Program
Start date.

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                          Rider B - Statement of Work
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B-2.1.3 REQUEST FOR DESIGN (RFD) - SITE

The Request for Design is a written notification to the Contractor from the
Commonwealth that the Contractor shall proceed with generation of a preliminary
site development design for consideration by the Commonwealth. The RFD will be
accompanied by a Site Information Package, in which the Commonwealth will
provide the Contractor with specific site details to the extent it is available.
Any information not available at the time the RFD is released, will be provided
to the Contractor during the initial site visit or upon approval of the
Preliminary Site Plan. Site Information Packages will be provided for either new
sites or existing sites that may require site development modification.

The Site Information Package (SIP) will consist of the site description
including: site location, latitude and longitude data, site elevation, legal
description, and travel directions; site access information including:
identification of any locked gates and key locations, land/site owner to include
a point of contact and telephone number, site use agreement, or authorization as
applicable. The SIP will also provide (if available) any known easements, zoning
or permit issues; access road, compound information, and existing utility
locations. Also included will be planned or existing: tower type, height,
lighting requirements, and ice bridges; shelter size and orientation, generator
size and positioning, fuel tank size and positioning, and existing or planned
foundation type and location. The Site Information Package will also provide
approximate tower and shelter loading to the extent that the appropriate tower,
shelter, and power/generator templates can be incorporated into the Preliminary
Site Plan. Inclusion or omission of any of the above data in the SIP, by the
Commonwealth does not relieve the Contractor of their responsibilities to gather
Site Planning and Design data as described in the RFP, the Proposal or the
Contract.

B-2.1.4 REQUEST FOR DESIGN (RFD) - REGION

The Request for Design - Region is a written notification from the Commonwealth
to the Contractor to proceed with generation of a regional development design,
incorporating the various approved SDDs, for consideration by the Commonwealth.
The RFD shall be reviewed as part of and shall generate the occurrence of the
Regional Design Review.

B-2.1.5 PRELIMINARY SITE PLAN (PSP)

The Contractor's initial response to the Commonwealth's Request for Design shall
consist of a Preliminary Site Plan. The PSP shall include the results of the
Contractor's land search, an annotated site sketch (to scale) noting the
location of any proposed and existing site infrastructure elements. These
elements include towers, (with existing antenna and microwave dish elevation),
shelters, generators, fuel tanks, foundations, utilities, fences and gates,
grounding, and guy wire and anchors.

For existing sites, the contractor will also propose a set of modifications to
the existing site infrastructure, that comply with the Commonwealth's Quality
Standards Manual, that will allow continued use by existing users concurrent
with the addition of the

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<PAGE>

                          Rider B - Statement of Work
--------------------------------------------------------------------------------

Commonwealth's system requirements. The modification detail shall include
sufficient product, cost, and schedule information necessary to enable the
Commonwealth to conduct a cost/benefit analysis of modifying the site versus
other available options.

B-2.1.6  SITE DESIGN DOCUMENT (SDD)

The Site Design Document is a Contractor deliverable outcome of the Site Design
Review and its associated process, as submitted to the Commonwealth for
approval, following approval of the Preliminary Site Plan (PSP). In conjunction
with approval of the PSP, the Commonwealth will direct the Contractor to proceed
with development of selected elements of the SDD as required on a site by site
basis. The SDD elements include the following items as defined in the RFP.

          >>       Site Survey
          >>       Vicinity Map
          >>       Boundary Map
          >>       Site Elevations
          >>       Compound Layout
          >>       Tower Location/Orientation
          >>       Access Road Design
          >>       Drainage Design
          >>       Grading Design
          >>       Foundations Design
          >>       Tower Design
          >>       Shelter Design
          >>       Geotechnical Report
          >>       Utility Design
          >>       Design Notes

B-2.1.7  SITE PRODUCTION RELEASE (SPR)

The Site Production Release is written confirmation from the Commonwealth to the
Contractor as a result of an approved SDD notifying the Contractor to proceed
with acquisition and staging of a Site, Sites, or Subsystems detailed in either
the approved SDD, or in a design of the Commonwealth's choosing. It is the
Commonwealth's intention to place quantity orders of towers, shelters, and
generators as soon as practicable following contract execution. These "bulk"
orders will be based on the Radio and Microwave Systems' Regional Design Reviews
and design templates provided by the Contractor, in order to expedite delivery
of these items for Site Development. The ordering of these items for a group of
sites prior to the completion of specific SDDs for those sites, may require the
Contractor to store or stage some of those items for use at a site in the next
region.

B-2.1.8 SITE DEPLOYMENT ORDER (SDO)

The Site Deployment Order is a written notification from the Commonwealth to the
Contractor to proceed with Installation at a particular Site or Sites. The SDO
will be issue following approval of the SDD and in accordance with the regional
schedule.

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                          Rider B - Statement of Work
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B-2.1.9   INTERFACE SPECIFICATIONS

The Contractor, along with the Radio and Microwave contractors, shall provide
its interface requirements to the Commonwealth's Program Office during the
Critical Design Review (CDR), and updated as necessary during Regional Design
Reviews (RDR) as deemed necessary by the Engineering and Quality Assurance
Contractor (EQAC). The Contractor shall incorporate interface requirements into
the system and subsystem designs as agreed to between the associated Contractors
via the Technical Interface Committee and as defined in the RFP.

B-2.1.10  DETAILED EQUIPMENT LIST

The Contractor identified the detailed equipment lists
on a regional basis in the Proposal. Equipment list updates will be provided at
the Preliminary Design Review (PDR), Critical Design Review (CDR), and each
Regional Design Review (RDR) as required.

B-2.1.11  DETAILED DESIGN DOCUMENT (DDD)

The Contractor, the Commonwealth and its Engineering and Quality Assurance
Contractor (EQAC) will jointly develop the DDD. The DDD consists of, but is not
limited to, the Contractor supplied Preliminary Design Document, Critical Design
Document, Regional Design Document, and Acceptance Test Plan.

B-2.1.11.1  PRELIMINARY DESIGN REVIEW (PDR) DOCUMENTATION PACKAGE

The PDR package defines the various tower and shelter templates jointly
developed by the Contractor, the Commonwealth and its Affiliates. The PDR
package will provide the contractor's life cycle; cost-benefit analysis based
recommendation for use of tower types. The same analysis shall be provided for
generators housed in an attached versus detached generator room, or installed on
an exterior concrete pad. The PDR package shall also include the Contractor's
Draft Site Quality Manual. The outcome of the PDR shall be a select set of
subsystem templates that will allow a streamlined approach to site design and
development.

B-2.1.11.2  CRITICAL DESIGN REVIEW (CDR) DOCUMENTATION PACKAGE

The CDR is the final site design review. The CDR package will consist of a final
set of site development templates as updated as a result of the PDR process. The
CDR shall also serve as the final review of the Acceptance Test Plan and QSM
prior to submission to the Commonwealth for approval. Each of these documents
will be updated as necessary and presented at Regional Design Review's (RDR)
held for each region(s).

B-2.1.11.3  REGIONAL DESIGN REVIEW (RDR) DOCUMENTATION PACKAGE

The RDR Documentation Package consists of the RDR presentation and the proposed
Regional Design Document (RDD). The RDR shall present the regional architecture,
site locations, equipment types, quantities and configurations. The RDR
documentation shall be traceable back to the CDR documentation baseline. The
result of the RDR shall be the creation of the approved Regional Design Document
(RDD).

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Site location and physical characteristics shall be finalized on a Regional
basis as part of the RDD. All design decisions are to be documented with
supporting analysis, trade-studies, and rationale. All site development is based
upon the Regional Design Document submitted by the Contractor, and approved by
the Commonwealth.

B-2.1.11.4    ACCEPTANCE TEST PLAN (ATP)

The Acceptance Test Plan forms a part of the Detail Design Document (DDD). The
ATP shall verify functionality and performance criteria from Subsystem through
Final System Acceptance. The ATP shall include Site Development Quality
Inspection Points (QIPs) identified by the Commonwealth. The successful
completion of ATP procedures shall demonstrate that all system performance
requirements are satisfied. Refer to Rider "H" Acceptance Testing

B-2.1.11.5    PREVENTIVE MAINTENANCE PLAN (PMP)

The Contractor shall deliver a preventive maintenance plan including schedules
and types of preventive maintenance and inspections to be performed on the
various subsystems, within 60 days of contract start date.

B-2.1.12   QUALITY STANDARDS MANUAL

The Contractor shall provide a Quality Standards Manual (QSM) to the
Commonwealth within 30 days of contract award. Development of the QSM is
captured by this WBS element. The QSM shall be updated at each RDR as required.
The following subjects at a minimum, to include detailed installation procedures
and reference to applicable industry regulatory standards that must be met by
the Contractor, will be addressed in detail as part of the manual.

B-2.1.12.1    DC POWER PLANT

To include but not limited to: battery subsystems, battery installation, rating
of batteries, charging systems.

B-2.1.12.2    CABLING

To include but not limited to: internal cabling, site wiring guidelines, power
cables, and control cables.

B-2.1.12.3    EQUIPMENT

To include but not limited to: tower, shelter, generator, and associated
subsystems and end items.

B-2.1.12.4    GROUNDING

To include but not limited to: electrostatic discharge considerations, ESD
guidelines, grounding at tower sites, grounding at cell sites, grounding at
building sites, and lightning arrestor.

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B-2.1.12.5    PHYSICAL CONFIGURATION

To include but not limited to: layout of equipment and general work area
requirements, anchoring of equipment racks and cabinets and support equipment,
subsystem/equipment plumb, equipment square, spacing guidelines, anchoring
guidelines, anchoring equipment to raised floors, overhead and wall mounting,
distribution frame configurations, distribution frame equipment connections, and
associated installation guidelines.

B-2.1.13      SITE DOCUMENTATION PACKAGE

Installation documentation shall be generated at the Factory and be available
on-site for installation. As-built documentation shall be generated from the
marked-up installation documentation following installation on site, and will be
included as part of the Site Documentation Review process.

The "As-Built" documentation package shall include, but is not limited to,
hardware configuration information, staging area build and test results, rack
drawings, cable and cabling drawings. It also shall contain the "System As-Built
Manual" (as defined in Project Logistics and Support, below) and final site
configuration including at a minimum: vendor product literature, block diagram,
rack diagrams, and electrical diagrams, hardware revision numbers.

B-2.1.14      TRAINING MANUALS

The Contractor shall provide training material for the
generators and the tower lighting kits.

B-2.1.15      MONTHLY PROJECT REPORT

Monthly reports shall be generated updating the status of all aspects of the
project including but not limited to schedule adherence, technical status,
milestone accomplishments, action items, and problem areas.

B-2.1.16      MBE, WBE, SERB QUARTERLY REPORT

Quarterly reports shall be generated updating the status of MBE, WBE, and SERB
project participation as defined in Rider A - Terms and Conditions.

PROGRAM REVIEWS

B-2.2.1       MONTHLY PROGRAM REVIEWS

The Monthly Program Status Review WBS collects the efforts associated with
preparing, conducting and attending the monthly program reviews. The program
reviews are held to review the project schedule (Reference Section B.2.1.2),
milestone accomplishments, technical status and any action items.

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B-2.2.2       CONTRACT IMPLEMENTATION REVIEW (CIR)

This WBS element collects the efforts associated with preparing and conducting
the meetings held to review all contract and systems performance requirements.
The CIR will be conducted in conjunction with the PDR.

B-2.2.3       PRELIMINARY DESIGN REVIEW (PDR)

The Design Review WBS element collects the Engineering effort associated with
conducting the formal design reviews held to ensure that the site development
design is complete. The PDR defines the various tower and shelter templates
jointly developed by the Contractor, the Commonwealth and its Affiliates in
accordance with the Commonwealth's requirements in the RFP. It is structured
to accomplish the following:

          >>       Technical review of the statewide system concept preliminary
                   design,

          >>       Authorization to proceed with detail design, and

          >>       Long lead item procurement approval.

One Preliminary Design Review (PDR) is scheduled and will be conducted within 15
days of Contract Award.

B-2.2.4       CRITICAL DESIGN REVIEW (CDR)

The CDR effort collects the engineering effort associated with conducting the
formal design reviews held to ensure that the system design is complete. The
purpose of CDR is to demonstrate that the detail design meets all specification
requirements. The CDR is structured to accomplish the following:

          >>       Critical technical review of the complete Site Development
                   design

          >>       Ensure that documents are complete and accurate

          >>       Ensure that all configuration items will perform as intended
                   and its functions meet all requirements, and

          >>       Ensure that configuration items can be serviced and
                   maintained as part of the system.

One Critical Design Review (CDR) is scheduled and will be conducted within 30
days of contract award.

B-2.2.5       REGIONAL DESIGN REVIEWS (RDR)

The Regional Design Review collects the engineering effort associated with
conducting the formal design reviews, held to ensure that the infrastructure
design for a particular Region is complete. The Contractor shall identify the
system architecture and all

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equipment on a site by site basis as part of each RDR. The result of the
Regional Design Review is the RDD.

One Regional Design Review (RDR) will be held for each region in response to a
Request For Design - Region.

B-2.2.6       TECHNICAL INTERFACE COMMITTEE REVIEWS

Technical Interface Committee (TIC) reviews will address any TIC issues
initiated, pending, or closed, during the preceding month, in the Contractor's
Monthly Program Review. See Paragraph B.1.3 for a discussion of the TIC process.

B-2.2.7       SITE-READY VERIFICATION REVIEW

The Site-Ready Verification Review is conducted by the Commonwealth in
conjunction with the Site Development Contractor to verify the physical ready
state of a site location. The Radio System and the Microwave System Contractors'
representatives will also be present for this review. The Site-Ready
Verification Review is conducted to verify the physical ready state of a site. A
single verification visit is planned per site and will be conducted following
Site Acceptance Testing. The Site Ready Verification Review process will be
included in the Acceptance Test Plan, and shall include the Contractor's
Responsibilities as detailed in the RFP and the Contract Riders.

B-2.2.8       SITE DOCUMENTATION REVIEW

The Site Documentation Review collects the efforts associated with preparing
Site Documentation Packages and conducting the Site Documentation review. This
includes, but is not limited to, "as-built" drawings, previously conducted test
results from completed site system and subsystem tests, the physical
installation records, and final equipment configuration lists.

B-2.2.9       FINAL CONTRACT CLOSE-OUT REVIEW

The Final Contract Review WBS collects the effort associated with preparing and
conducting the final contract review. The final contract review is held with the
Customer to review that all deliverables, system requirements, and contractual
commitments have been met.

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B-3      SHELTERS

The shelter system is defined as a set of specific combinations or
configurations intended to meet the requirements for the radio and microwave
subsystems.

SHELTER DESIGN

The majority of the Statewide Voice and Data Radio System sites will require new
radio equipment shelters, towers, and emergency generators to support the
communications infrastructure equipment. The shelter system will be defined as a
set of specific combinations or configurations intended to meet the requirements
for the radio and microwave subsystems. These requirements were defined in the
RFP and under the following sections.

B-3.1.1       REQUIREMENTS

All shelter configurations will have basic requirements that have been utilized
to define the basic building block for each type of shelter defined in the RFP.
These basic requirements are the same for all shelters and are independent of
the size of the shelter or the existence of a generator room. The following
listings of basic requirements are defined in the RFP.

BASIC SHELTER REQUIREMENTS:

          >>       Wiring and Conduit Requirements
          >>       Telephone Cable Entry
          >>       Concrete Entrance Ramp
          >>       Radio Shelter Alarms
          >>       Bulletproof Construction
          >>       Meet Zone II for Earthquakes
          >>       Installation of Generator Transfer Switch
          >>       Automatic Transfer Switch
          >>       Manual Transfer Switch
          >>       Fire Extinguisher
          >>       Shelter Grounding system
          >>       Interior Lighting System
          >>       Exterior Lighting System
          >>       Cable Ladder Trays
          >>       Cable Entry Ports
          >>       Flooring Requirements
          >>       Shelter Foundation Design
          >>       Shipping/Delivery Charges
          >>       Off-Loading
          >>       2 Year Warranty Maintenance

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B-3.1.2  VARIABLE REQUIREMENTS

In addition, there are variable requirements. As shelter sizes increase these
variable requirements may require more material, increase in capacity, or
replacement of a specific item to provide required functional performance. The
Contractor shall provide the following variable requirements as detailed in the
RFP and as selected by the Commonwealth as part of the Site Design Document
(SDD) approval process. The following listings of variable requirements are
defined in the RFP.

    VARIABLE SHELTER REQUIREMENTS:

          >>       AC Power & Electrical Service Capacity and Distribution
          >>       Main Distribution Panel
          >>       Heating and Air Conditioning
          >>       Patch Block Mounting Surface
          >>       Exterior Radio Shelter Fascia Style

B-3.1.3  OPTIONAL REQUIREMENTS

There are also optional features that may be applied to any shelter, as
required, on a site by site basis. These optional features are IN ADDITION to
the basic or variable requirements of any shelter configuration. In some
specific circumstances, an optional feature may all together replace a basic or
variable requirement. The following listings of optional requirements are
defined in the RFP.

    OPTIONAL SHELTER REQUIREMENTS:

          >>       DC Power Plant and Batteries
          >>       Generator Room
          >>       Fire Suppression
          >>       Installation of Emergency Generator
          >>       Manual Transfer Switch
          >>       Removal of Existing Shelter Foundation
          >>       Removal of Existing Shelter
          >>       Warranty - 3 Year Extended Warranty Maintenance
          >>       Maintenance - 2 Year
          >>       Maintenance - 3 Year Extended

SHELTER STANDARDS

All shelter materials, design and construction procedures shall be in accordance
with the applicable codes as defined in the Site Development RFP, the Proposal,
and the Contract including the following.

B-3.2.1 BUILDING CODES

The shelter structural requirements shall comply with all federal, state and
local building codes including the latest edition of the Uniform Building Code
(UBC).

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B-3.2.2  ELECTRICAL CODES

Installation of all electrical equipment, power distribution, lighting and
outlet assemblies, alarms and grounding systems with associated wireways and
wiring shall comply with the most recent edition of the National Electrical Code
(NEC), National Fire Protection Association (NFPA) and Occupational Safety and
Health Administration (OSHA).

All electrical equipment and devices shall be listed, approved or certified by
Underwriters Laboratories (UL) when available.

SHELTER PERFORMANCE

The radio shelter designs shall be supplied in six- (6) different exterior
dimensions for radio equipment, ranging from 12 ft. x 8 ft. to 12 ft. x 30-ft.
in size.

B-3.3.1  SHELTER EMERGENCY GENERATOR ROOM

The shelters shall be capable of being supplied with or without attached
emergency generator rooms. Generator rooms shall be considered options and thus
all shelter configurations must support the inclusion or exclusion of this
option. Shelters with attached emergency generator rooms shall not reduce the
internal size of the radio equipment room. The following dimensions are
specified in order to develop the overall requirements for the Statewide Radio
System.

B-3.3.2  SHELTER DIMENSIONS

EXTERIOR DIMENSIONS WITH MINIMUM FLOOR TO CEILING HEIGHTS OF 9 FT. 6 INCH.
(Ceiling height requirements apply to all shelter configurations)

          >>       12 ft. by 8 ft.

          >>       12 ft. by 12 ft.

          >>       12 ft. by 16 ft.

          >>       12 ft. by 20 ft.

          >>       12 ft. by 24 ft.

          >>       12 ft. by 30 ft.

SHELTER CONFIGURATIONS

As shelter sizes increase or decrease, some of the basic and optional
requirements shall be upgraded or downgraded in size, capacity or change in some
way to meet the intent of the functionality and performance requirements.

Shelter construction shall be TYPE I CONCRETE AGGREGATE, TYPE II FIBERGLASS, OR
TYPE III STEEL exterior with plywood interior walls capable of meeting
bulletproof requirements. Roofing shall be designed to prevent penetration by
ice falling from the tower at the site.

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The roof shall be designed to prevent accumulation and penetration of water.
Interior walls shall be designed to allow mounting of electrical and electronic
equipment.

B-3.4.1   SHELTER ACCEPTANCE

Title to and ownership of all equipment or systems shall remain with the
contractor until the equipment is delivered, successfully installed and
operational at the radio site, as characterized in the acceptance test plan. The
Commonwealth's acceptance date shall occur after the equipment has passed the
acceptance test.

B-3.4.2   SHELTER DELIVERY

Shelter deliveries shall be coordinated through the Contractor's Harrisburg
Office to the Radio Project Office via Expedition and SureTrak.

Every package, bill of lading, shipping memorandum and invoice shall be marked
with a purchase order or number of the Commonwealth. An itemized delivery
ticket, bearing the Commonwealth's purchase order number shall be provided with
the goods to insure their receipt. If a carrier makes a delivery for the
Contractor, then an itemized delivery ticket shall be attached to the outside of
the package.

Delivery ticket and purchase order numbers of delivered items shall be tracked
via Expedition.

SHELTER SUBMITTALS

The radio shelter contractor shall be responsible for submitting appropriate
engineering drawings to obtain local approvals for site development, in
accordance with Commonwealth policy directives. The following items are primary
submissions but may not necessarily be totally inclusive of all required
submissions.

B-3.5.1   ENGINEERING DRAWINGS

The radio shelter contractor shall prepare and submit for approval, engineering
drawings of the shelter depicting its overall dimensions, electrical layout and
floor plan, as part of the SDD. These drawings will be used, as required, for
obtaining zoning and building permits.

A Registered Professional Engineer licensed in the Commonwealth of Pennsylvania
will seal drawings.

B-3.5.2   ELECTRICAL DESIGN DRAWINGS

The Contractor shall provide electrical design drawings for review and approval
by the Commonwealth.

Six (6) sets of approval drawings for the radio shelters shall consist of a line
diagram (indicating power distribution for both shelters and circuit directories
of power panels

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etc.), Electrical plans for both equipment and radio shelters indicating
physical locations of equipment/devices such as power equipment, lighting &
outlets etc. with associated wiring & Electrical Bill of Materials for all
equipment, devices, conduit and wire shall be submitted to the Commonwealth.

Approval Drawings shall be updated with the Commonwealth's comments and six (6)
sets of Final Drawings shall be submitted to the Commonwealth for its records.
Final drawings shall be identical to the "As-Built" installation condition of
each shelter.

A registered professional engineer licensed in the Commonwealth of Pennsylvania
shall seal drawings.

B-3.5.3   FOUNDATION DESIGN DRAWINGS

The Contractor shall submit, for approval, a suitable foundation design based
upon normal soil conditions per ANSI/TIA/EIA-222-F (or latest version). Final
foundation design and cost shall be determined on receipt of soil boring
information. A registered professional engineer licensed in the Commonwealth of
Pennsylvania shall seal drawings.

SHELTER INSTALLATION

The radio shelter contractor shall be responsible for installing the shelter.
The following items are primary submissions but may not necessarily be totally
inclusive of all required submissions.

B-3.6.1   INSTALLATION REQUIREMENTS

The Contractor shall be responsible for the installation of the shelter products
to be provided, in accordance with the RFP. The following describes the
requirements and responsibilities of the Contractor.

          >>      All installation work performed shall be in accordance with
                  laws, regulations and ordinances, of all State, Local, and
                  Federal agencies.

          >>      The contractor shall provide all the necessary personnel,
                  tools, equipment, and transportation for the installation of
                  all equipment provided.

          >>      The contractor shall ensure that all material and components
                  are delivered to the proposed sites in a timely manner.

          >>      The contractor is responsible for the complete and proper
                  installation of any and all supplied shelter equipment
                  furnished in accordance with this RFP. The contractor shall
                  provide all the necessary hardware and supplies.

Notwithstanding the details presented in the RFP and the Proposal, it is the
responsibility of the contractor's project manager to verify the correctness of
the

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material lists and suitability of devices proposed in the SDD and various
Shelter Design Templates.

B-3.6.2 SHELTER INSTALLATION AT OPERATIONAL SITES

All existing radio communications systems shall remain fully operational during
the installation of the provided equipment and until the Commonwealth provides
final acceptance. Because existing systems support public safety operations,
interruptions in service due to contractor or subcontractor activities cannot be
tolerated.

If any interruptions in service are deemed by the contractor to be unavoidable,
written notification detailing the nature and duration of such interruptions
shall be provided to the Commonwealth for review and approval.

CONTRACTOR RESPONSIBILITIES

The shelter contractor shall have turnkey responsibility for the delivery,
installation and acceptance testing of the shelters. In order to develop a
complete and operational system, the points of demarcation between systems and
all contractors is critical to the system implementation process. Therefore, the
Shelter Contractor's responsibilities are defined. The Contractor's
Responsibilities listed apply to those commodities and subsystems included in
each approved Site Design Document.

Contractors shall follow good engineering practices in the preparation,
administration, implementation, inspection and acceptance of each individual
subsystem at the designated sites.

The Site Development Contractor shall be the responsible party for site
management and act as the general site manager for all construction and
coordination between contractors, vendors and the Commonwealth until Final Site
Acceptance by the Commonwealth. The Contractors shall comply with the following
representative sequence and order of subsystem installations.

B-3.7.1   SHELTER SUBSYSTEM TO GENERATOR SUBSYSTEM VENDOR INTERFACE

          >>      The shelter subsystem vendor shall install the following
                  generator equipment in the shelter per the RFP; Automatic
                  transfer switch

          >>      Exterior manual transfer switch (supplied by the shelter
                  manufacturer)

          >>      Exterior portable generator plug

The shelter subsystem vendor shall perform the following electrical connections
to the generator equipment per the RFP.

    ATTACHED GENERATOR ROOM CONFIGURATION

          >>      Automatic transfer switch to the main electrical distribution
                  panel

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          >>      Portable generator plug to the manual transfer switch

          >>      Manual transfer switch to the automatic transfer switch

    DETACHED GENERATOR ROOM CONFIGURATION

          >>      Automatic transfer switch to the main electrical distribution
                  panel

          >>      Portable generator plug to the manual transfer switch

          >>      Manual transfer switch to the automatic transfer switch

          >>      Utility AC power from main distribution panel to sub-fed
                  detached generator room distribution panel

    OUTSIDE GENERATOR CONFIGURATION

          >>      Automatic transfer switch to the main electrical distribution
                  panel

          >>      Portable generator plug to the manual transfer switch

          >>      Manual transfer switch to the automatic transfer switch

The shelter subsystem vendor shall perform the following connections from
interior shelter ground system to the generator equipment:

    ATTACHED GENERATOR ROOM CONFIGURATION

          >>      Automatic transfer switch

          >>      Manual transfer switch

    DETACHED GENERATOR ROOM CONFIGURATION

          >>      Automatic transfer switch

          >>      Manual transfer switch

          >>      Detached generator room distribution panel

The shelter subsystem vendor shall perform the following connections from
exterior shelter ground system to the generator equipment:

    OUTSIDE GENERATOR CONFIGURATION

          >>      Automatic transfer switch

          >>      Manual transfer switch

The shelter subsystem contractor shall provide the following information to the
Generator System contractor per the RFP.

    ATTACHED GENERATOR ROOM CONFIGURATION

          >>      Shelter floor plan indicating equipment locations

    DETACHED GENERATOR ROOM CONFIGURATION

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          >>      Shelter floor plan indicating equipment locations

          >>      Location of AC outlets or detached generator room distribution
                  panel for generator battery charger and block heater power
                  connections

    OUTSIDE GENERATOR

          >>      Shelter floor plan indicating equipment locations

B-3.7.2  SHELTER SUBSYSTEM TO TOWER SUBSYSTEM VENDOR INTERFACE

The shelter subsystem vendor shall install the following tower equipment into
the shelter per the RFP.

          >>      Tower light control panel

The shelter subsystem vendor shall perform the following electrical connections
to the tower equipment per the RFP.

          >>      Main distribution panel to tower light control panel

The shelter subsystem vendor shall perform the following connections from
interior shelter ground system to the tower equipment:

          >>      Tower light control panel

The shelter subsystem vendor shall provide the following information to the
tower subsystem vendor per the RFP.

          >>      Shelter floor plan indicating equipment locations and
                  locations of entrance ports for conduits to detached generator
                  room, electrical service entrance, and extensions from
                  interior ground halo to exterior ground halo.

B-3.7.3  SHELTER SUBSYSTEM VENDOR TO MICROWAVE SYSTEM CONTRACTOR INTERFACE

The shelter subsystem vendor responsibilities, including all required material
and labor, shall be comprised of, but not be limited to, the following tasks:

The shelter subsystem vendor shall provide the following information to the
Microwave System Contractor per the RFP.

          >>      Shelter floor plan indicating equipment locations

          >>      Available power connection requirements:

          >>      DC power: location of shelter DC power plant for the DC buss
                  connection

          >>      AC power: location of AC outlets

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B-3.7.4  SHELTER SUBSYSTEM VENDOR TO RADIO SYSTEM CONTRACTOR INTERFACE

The shelter subsystem vendor responsibilities, including all required material
and labor, shall be comprised of, but not be limited to, the following tasks:

The shelter subsystem vendor shall provide following information to the Radio
System contractor per the RFP.

          >>      Shelter floor plan indicating equipment locations

          >>      DC power: location of shelter DC buss for connection

          >>      AC power: location of AC outlets

B-3.7.5  ADDITIONAL SHELTER SUBSYSTEM VENDOR RESPONSIBILITIES

In addition to the previously described tasks, the shelter system contractor
responsibilities, including all required material and labor, shall be comprised
of, but not be limited to, the following tasks per the RFP.

B-3.7.5.1    EQUIPMENT

The shelter subsystem vendor shall install the following equipment into the
shelter per the RFP.

          >>      HVAC

          >>      Fire suppression system

          >>      Interior/exterior lighting systems

          >>      Interior/exterior AC outlets

          >>      Main and UPS electrical distribution panels

          >>      Maintenance bypass switch

          >>      Emergency interior light(s)

B-3.7.5.2    ELECTRICAL

The shelter subsystem vendor shall perform the following electrical connections
per the RFP.

          >>      HVAC

          >>      Fire suppression system

          >>      Interior/exterior lighting systems

          >>      Interior/exterior AC outlets

          >>      Emergency interior light(s)

          >>      UPS system to UPS distribution panel

          >>      Maintenance bypass switch to UPS system and UPS distribution
                  panel

          >>      Main distribution panel to maintenance bypass switch

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B-3.7.5.3    INTERIOR SHELTER HALO GROUNDING

The shelter subsystem vendor shall perform the following connections to the
interior shelter ground system per the RFP.

          >>      HVAC

          >>      Fire suppression system

          >>      Main electrical distribution panels

          >>      DC power system

          >>      Maintenance bypass switch

          >>      All metal objects not previously indicated, including cable
                  ladders, doors and doorframes (utilizing a copper strap, etc.)

B-3.7.5.4    EXTERNAL GROUND SYSTEM

Shelter System contractor shall perform the following connections to the
external shelter ground system per the RFP.

          >>      Connect shelter to external ground system per specifications

B-3.7.5.5    OTHER RESPONSIBILITIES

The shelter subsystem vendor shall deliver shelters to site and set up the
shelter subsystems per the RFP.

          >>      Coordinate shelter delivery to the site

          >>      Deliver the shelter to the site

          >>      Offload, install, and position the shelter per specifications

          >>      Shelter vendor to perform shelter Subsystem ATP

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B-4      EMERGENCY GENERATOR

The generator system is defined as a set of specific combinations or
configurations intended to meet the requirements for the radio and microwave
subsystems.

EMERGENCY GENERATOR DESIGN

The majority of the Statewide Voice and Data Radio System sites will require new
emergency generators to support the communications infrastructure equipment. The
generator system will be defined as a set of specific combinations or
configurations intended to meet the requirements for the radio and microwave
subsystems. These requirements were defined in the RFP and under the following
sections.

EMERGENCY GENERATOR PERFORMANCE

The emergency generator designs shall be supplied in seven (7) different
capacities ranging from 8 kW to 100 kW in size per the RFP.

EMERGENCY GENERATOR CONFIGURATIONS

The following list represents the minimum functionality, performance, or quality
requirements that shall be included in each emergency generator configuration.
The following list defines the required functionality or the specific
requirements of the Emergency Generator per the RFP.

          >>      Emergency Generator

          >>      Wiring and Conduit

          >>      Generator Alarms

          >>      Grounding

          >>      Patch Blocks

          >>      Generator Foundation

          >>      Industrial Rated Engine with Skid Base

          >>      Block Heater

          >>      Exhaust Silencer

          >>      Alternator

          >>      Voltage Regulator

          >>      Battery and Charger

          >>      Full Load Pick-Up

          >>      Liquid Cooled System

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          >>      Generator Set Control System (per NFPA 110)

          >>      On-Site/ Checkout

          >>      Fuel Tank Capacity (1 day and 7 days)

          >>      Automatic Transfer Switch with Exerciser Clock (100, 200, and
                  400 Amps)

          >>      Manual Transfer Switch (100, 200, and 400 Amps)

          >>      Propane Tank Burial

          >>      Off Site Installation

          >>      Cost for Shipping of Generator to Shelter Manufacturer

          >>      Weather Protective Enclosure and Silencer

          >>      Sub-Base Diesel Fuel Tanks

          >>      Removal Of Old Generator

          >>      Removal Of Existing Generator Foundation

          >>      Portable Generator

EMERGENCY GENERATOR SHIPPING AND DELIVERY PROCESS

Shelter deliveries shall be coordinated through the Contractor's Harrisburg
Office to the Radio Project Office via Expedition and SureTrak.

Every package, bill of lading, shipping memorandum and invoice shall be marked
with a Commonwealth purchase order number. An itemized delivery ticket, bearing
the Commonwealth's purchase order number shall be provided with the goods to
insure their receipt. If a carrier makes a delivery for the Contractor, then an
itemized delivery ticket shall be attached to the outside of the package.
Delivery ticket and purchase order numbers of delivered items shall be tracked
via Expedition.

B-4.4.1      EMERGENCY GENERATOR FINAL SHIPPING DESTINATION

The shelter contractor may be responsible for the shipping of the generators,
depending upon the final arrangements between the generator and shelter
contractors. The shelter and generator contractors are totally responsible for
providing safe transportation and delivery of all materials provided within the
shelter and emergency generator specifications. The shipment from the place of
origin to designated locations within the Commonwealth of Pennsylvania are to be
covered by these two contractors as related to the provided two products and as
further define in the RFP Section 5.7 - Shipping and Delivery Charges.

EMERGENCY GENERATOR SUBMITTALS

The radio Emergency Generator contractor shall be responsible for submitting
appropriate engineering drawings. The following items are primary submissions
but may not necessarily be totally inclusive of all required submissions.

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B-4.5.1 ENGINEERING DRAWINGS

The Emergency Generator contractor shall prepare and submit for approval,
engineering drawings sets for the emergency generator. These specific drawings
shall be as follows;

          >>      Interconnection Wiring Schematic Diagrams

          >>      Alarm Wiring Schematic Drawings

GENERATOR INSTALLATION

All installation work performed shall be in accordance with laws, regulations
and ordinances of all State, Local, and Federal agencies. The contractor shall
provide all the necessary personnel, tools, equipment, and transportation for
the installation of all equipment provided per the RFP specification. It shall
be the responsibility of the contractor to provide a turnkey installation of the
provided equipment. Optimization, trouble shooting, and adjustment of each
subsystem shall be the contractors responsibility.

GENERATOR WARRANTY

A no deductible warranty that provides for on site service by a factory
authorized service contractor shall be provided. This warranty shall provide
coverage against all defects in materials and workmanship as defined in Rider F
- Warranty and Maintenance.

CONTRACTOR RESPONSIBILITIES

The generator system contractor shall have turnkey responsibility for the
delivery, installation and acceptance testing of the generators. In order to
develop a complete and operational system, the points of demarcation between
systems and all contractors is critical to the system implementation process.
Therefore, the Generator Contractor's responsibilities are defined. The
Contractor's Responsibilities listed apply to those commodities and subsystems
included in each approved Site Design Document.

Contractors shall follow good engineering practices in the preparation,
administration, implementation, inspection and acceptance of each individual
subsystem at the designated sites.

The Site Development Contractor shall be the responsible party for site
management and act as the general site manager for all construction and
coordination between contractors, vendors and the Commonwealth until Final Site
Acceptance by the Commonwealth. The Contractors shall comply with the following
representative sequence and order of subsystem installations.

B-4.8.1 SHELTER SUBSYSTEM

The generator system contractor responsibilities, including all
required material and labor, shall be comprised of, but not be limited to, the
following tasks:

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The Generator System contractor shall provide the following
items to the Shelter System contractor per the RFP.

          >>      Automatic transfer switch

          >>      Manual transfer switch

          >>      Generator

          >>      Portable generator receptacle

The Generator System contractor shall perform the installation of following
equipment into the shelter per the RFP.

    ATTACHED GENERATOR ROOM CONFIGURATION

          >>      Generator and all related accessories or attachments

          >>      RJ45 patch block for generator alarms

    DETACHED GENERATOR ROOM CONFIGURATION

          >>      Generator and all related accessories or attachments

          >>      Two (2) RJ45 patch blocks for generator alarms

          >>      One (1) located in detached generator room

          >>      One (1) located in equipment shelter

    OUTSIDE GENERATOR CONFIGURATION

          >>      Generator and all related accessories or attachments

          >>      One (1) RJ45 patch blocks for generator alarms located in
                  equipment shelter

          >>      Connection of alarms on a terminal strip at the generator

The Generator System contractor shall perform the following electrical
connections in the shelter per the RFP.

    ATTACHED GENERATOR ROOM CONFIGURATION

          -       Generator to manual transfer switch

          -       All generator/transfer switch alarms to generator alarm patch
                  block

    DETACHED GENERATOR ROOM CONFIGURATION

          >>      Generator to manual transfer switch

          >>      All generator/transfer switch alarms to generator alarm patch
                  block in detached generator room, through conduit provided
                  between detached generator room and equipment shelter, to
                  second generator alarm patch block in equipment shelter

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          >>      Generator battery charger

          >>      Generator block heater

    OUTSIDE GENERATOR CONFIGURATION

          >>      Generator to manual transfer switch

          >>      All generator/transfer switch alarms to generator alarm patch
                  block in detached generator room, through conduit provided
                  between detached generator room and equipment shelter, to
                  second generator alarm patch block in equipment shelter

          >>      Generator battery charger

          >>      Generator block heater

The Generator System contractor shall perform the following connections to the
interior/exterior ground system

    ATTACHED GENERATOR ROOM CONFIGURATION

          >>      Generator engine block to interior ground system

          >>      Alternator to interior ground system

    DETACHED GENERATOR ROOM CONFIGURATION

          -       Generator engine block to exterior ground system

          -       Alternator to exterior ground system

    OUTSIDE GENERATOR CONFIGURATION

          >>      Generator engine block to exterior ground system

          >>      Alternator to exterior ground system

The Generator System contractor shall provide the following information to the
Shelter System contractor per the RFP.

          >>      Electrical loads of all equipment

          >>      Thermal loads of all equipment

          >>      Amount of floor space required

          >>      Floor loading requirement

          >>      Requested location in shelter for equipment

B-4.8.2 TOWER SUBSYSTEM

Tower System contractor shall perform the following site construction pertaining
to the generator equipment per the RFP.

    ATTACHED GENERATOR ROOM CONFIGURATION

          >>      Provide extension ground cable(s) from exterior halo ground
                  system to be bonded to fuel tank(s)

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          >>      Construct foundation(s) for fuel tank(s)

    DETACHED GENERATOR ROOM CONFIGURATION

          >>      Provide extension ground cable(s) from exterior halo ground
                  system to be bonded to fuel tank(s)

          >>      Provide three (3) extension ground cables from exterior halo
                  ground system to be routed into the detached generator room
                  for bonding to generator engine block, alternator, and
                  electrical distribution panel

          >>      Install generator AC power, alarm/control, and utility AC
                  power conduits from shelter to detached generator room

          >>      Construct foundation(s) for fuel tank(s) and detached
                  generator room

    OUTSIDE GENERATOR CONFIGURATION

          >>      Provide extension ground cable(s) from exterior halo ground
                  system to be bonded to fuel tank(s)

          >>      Provide three (3) extension ground cables from exterior halo
                  ground system to be routed into the detached generator room
                  for bonding to generator engine block, alternator, and
                  electrical distribution panel

          >>      Install generator AC power, alarm/control, and utility AC
                  power conduits from shelter to detached generator room

          >>      Construct foundation(s) for fuel tank(s) and detached
                  generator room

B-4.8.3     MICROWAVE SUBSYSTEM

Generator System contractor shall provide the following information to the
Microwave System contractor per the RFP.

          >>      Equipment list and description of generator alarms to be
                  interfaced with network management system

B-4.8.4     RADIO SUBSYSTEM

Generator System contractor shall provide the following information to
the Radio System contractor per the RFP.

          >>      List and description of generator alarms to be interfaced with
                  network management system

B-4.8.5     CIVIL CONTRACTOR

Generator System contractor shall provide the following information to the Civil
contractor per the RFP.

    ATTACHED GENERATOR ROOM CONFIGURATION

          >>      Requested locations for fuel tank(s)

    DETACHED GENERATOR ROOM CONFIGURATION

          >>      Requested locations for fuel tank(s)

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          >>      Floor plan of detached generator room indicating locations for
                  generator AC power, alarm/control, and utility AC power
                  conduits and exterior ground extension cables

    OUTSIDE GENERATOR CONFIGURATION

          >>      Requested locations for fuel tank(s)

          >>      Floor plan of detached generator room indicating locations for
                  generator AC power, alarm/control, and utility AC power
                  conduits and exterior ground extension cables

B-4.8.6  ADDITIONAL GENERATOR SUBSYSTEM VENDOR RESPONSIBILITIES

In addition to the previously described tasks, the generator system contractor
responsibilities, including all required material and labor, shall be comprised
of, but not be limited to, the following tasks per the RFP.

PERFORM THE INSTALLATION OF THE FOLLOWING EQUIPMENT ON SITE

          >>      Fuel tank(s) and fuel line(s) from fuel tank to generator.
                  Shall including proper fuel filters, vapor traps and automatic
                  fuel shut off valve

          >>      Make all necessary and required connections

          >>      Connect fuel tank(s) to exterior ground system

          >>      Deliver generators and perform setup of generator subsystems

          >>      Perform generator subsystem ATP

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B-5      TOWERS

The tower system is intended to support the two-way voice, data, and microwave
communications equipment for the Commonwealth of Pennsylvania Statewide Radio
System. The Commonwealth shall define the actual types, heights and locations
based upon the final radio and microwave system designs.

The Commonwealth has developed requirements for towers and has composed a set of
specifications. The RFP defines basic and optional requirements to support the
system implementation of the microwave and radio subsystems. The following
defines these requirements and tasks as provided in the RFP.

TOWER DESIGN

All towers will have basic requirements. These basic requirements are the same
for all towers. An example of a basic requirement is wind loading of 80 mph with
concurrent 1/2-inch radial ice (non-derated). The performance of this
requirement is independent of the size of the tower, material type, or the
foundation design.

In addition to basic requirements, there will also be variable requirements. As
tower sizes increase these variable requirements may require more material,
increase in capacity, or replace a specific item to provide required
performance. An example of a variable requirement is the use of different tower
members to support different antenna loads. The tower members need to be
stronger in order to support greater antenna loads.

There will also be variable features that can be applied to any tower as
required on a site by site basis. These variable features shall be in addition
to the basic requirements of any tower. In some specific circumstances, an
optional feature may altogether replace a basic requirement. This is noted in
the RFP. An example of a variable feature is the type of tower lighting. Some
tower locations may require different lighting systems due to FAA regulations or
local zoning. This will be determined during the microwave and radio systems
procurements.

TOWER PERFORMANCE

The following list defines the functionally and requirements as needed to
develop and implement the Statewide Radio System. The Commonwealth will define
the towers to the Tower Contractor based on the following criteria.

The following general requirements and tasks apply to all towers per the RFP.

          >>      Tower Heights

          >>      Type of Tower

          >>      Wind and Ice Loading

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          >>      Tower Member Construction Types

          >>      Tower Design

TOWER CONFIGURATION

The following list of basic, variable and optional requirements represents the
minimum functionality, performance, or quality requirements that shall be
included in each tower design per the RFP. The list is not necessarily totally
inclusive of all requirements.

          >>      Tower Loading and Stress Design
          >>      Tower Twist, Sway and Displacement
          >>      Tower Grounding System
          >>      Transmission Line Cable Ladder System
          >>      Climbing Ladder
          >>      Waveguide Bridge
          >>      Tower Foundation Design
          >>      Tower Loading
          >>      Wind and Ice Loading
          >>      Tower Painting
          >>      Tower Lighting
          >>      Wiring and Conduit Requirements
          >>      Tower Alarms
          >>      Microwave Dish Ice Shields
          >>      Disassembling And Removal Of Existing Tower
          >>      Removal Of Existing Tower Foundations

TOWER SUBMITTALS

The tower drawing package will be specifically developed and packaged by the
tower vendor for each site. This drawing package will contain Key Erection and
Secondary Drawings per the RFP and shall be submitted in accordance with Section
B.2.

    KEY ERECTION DRAWINGS

    The key erection drawings will include, but not be limited to, the
following:

          >>      Site name

          >>      List of all secondary drawings

          >>      Chart of complete antenna/waveguide data

          >>      Elevation View to include tower member descriptions, assembly
                  and erection details

          >>      Guy wire information (Changes in elevation, sizes, etc.)

          >>      A plan view of the tower showing guy wire azimuth,
                  transmission line ladder, climbing ladder and transmission
                  lines

    SECONDARY DRAWINGS

    Secondary drawings will include:

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          >>      Foundation drawings with all necessary details shown

          >>      Lighting kit installation

          >>      Grounding

          >>      Packing list showing part number, sizes and weights of
                  associates materials

          >>      Antenna mounting detail

          >>      Installation of any miscellaneous appurtenances

          >>      Cable bridge detail

    DRAWING PACKAGES

    When drawing packages are sent to the Commonwealth, in addition to the
    requirements of Section B.2, the following practices shall apply:

          >>      Two blue/black line sets shall be issued to the Commonwealth
                  for field construction.

          >>      Three sets of design calculations and computer analysis will
                  be provided to the Commonwealth in the

                  final site package.

TOWER SHIPPING AND DELIVERY

Tower deliveries shall be coordinated through the Contractor's Harrisburg Office
to the Radio Project Office via Expedition and SureTrak.

Every package, bill of lading, shipping memorandum and invoice shall be marked
with a Commonwealth purchase order number. An itemized delivery ticket, bearing
the Commonwealth's purchase order number shall be provided with the goods to
insure their receipt. If a carrier makes a delivery for the Contractor, then an
itemized delivery ticket shall be attached to the outside of the package.

Delivery ticket and purchase order numbers of delivered items shall be tracked
via Expedition.

The tower contractors are totally responsible for providing safe transportation,
delivery and off-loading of all materials provided within the tower
specification from the place of origin to designated locations within the
Commonwealth of Pennsylvania. ALL costs to ship the tower are the responsibility
of the tower manufacturer. This includes shipping, delivery to site, and
off-loading of the tower at the site.

All packaging of materials shall conform to good packing practices to protect
against any possible shipping damage.

The tower contractor shall ascertain site suitability for off loading prior to
shipment of any tower steel or components.

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Tower packaging and shipping shall be arranged to preclude damage to steel or
galvanizing during transport and off loading.

After off loading at the site, the tower manufacturer will inventory all
materials. Any discrepancies in quantity, quality or content shall be reported
immediately to the Commonwealth's project manager.

Delivery shall be made to ensure that the system is installed to meet the
Commonwealth's critical dates as defined in Rider D and the Master Program
Schedule. The contractor shall indicate how equipment or systems will be
delivered, i.e. identifying the carrier, and shall notify the Commonwealth's
Project Manager of firm shipping and delivery dates. The Commonwealth's Project
Manager shall be informed of any changes in shipping and delivery dates.

Title to and ownership of all equipment or systems shall remain with the
contractor until the equipment is delivered, successfully installed and
operational at the radio site, as characterized in the acceptance test plan. The
Commonwealth's acceptance date shall occur after the equipment has passed the
acceptance test.

Delivery of partial shipments is not acceptable unless authorized by the Radio
Project Office.

Charges for express freight, cartage, or packing that deviates from the contract
shall not be allowed or paid by the Commonwealth, unless otherwise expressly
stated by the Commonwealth.

Every package, bill of lading, shipping memorandum and invoice shall be marked
with a purchase order number of the Commonwealth.

An itemized delivery ticket, bearing the Commonwealth's purchase order number
shall be provided with the goods to insure their receipt. If a carrier makes a
delivery, then an itemized delivery ticket shall be attached to the outside of
the package.

TOWER INSTALLATION

All installation work performed shall be in accordance with laws, regulations
and ordinances, of all State, Local, and Federal agencies.

The contractor shall provide all the necessary personnel, tools, equipment, and
transportation for the installation of all equipment provided.

The Commonwealth has critical deadlines for the implementation phase of the
project. Site Development requires that site design work begin immediately
following contract

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award to meet these critical dates. The contractor shall ensure that all
material and components are delivered to the proposed sites.

It shall be the responsibility of the contractor to provide a turnkey
installation of the provided equipment. Optimization, trouble shooting, and
adjustment of each subsystem shall be the contractors responsibility. This
includes any changes and/or additions in order to meet performance criteria. Any
additional equipment required after the contract is awarded to meet the system
performance criteria of the defined standards and/or specifications shall be at
the sole expense of the contractor unless the Commonwealth issues a change order
or an addition to Rider C

Equipment shall be installed in a neat and workman like manner, in accordance
with good practice, by competent technicians or mechanics. Personnel designated
by the Commonwealth shall complete inspection and approve all installations.
Such approval shall be limited in scope to the specific subsystem physical
installation, and shall not be construed to imply full acceptance of the system,
or subsystem.

Notwithstanding the details presented in these specifications, it is the
responsibility of the contractor's project manager to verify the correctness of
the material lists and suitability of devices proposed to meet the intent of the
specifications. The contractors shall be responsible for providing or arranging
for all parts necessary for the equipment and its installation up to and
including final system acceptance.

TOWER WARRANTY AND MAINTENANCE

The Tower Contractor shall provide warranty and maintenance for the supplied
products as required by the RFP and as defined in Rider F - Warranty and
Maintenance.

CONTRACTOR RESPONSIBILITIES

The tower system contractor shall have turnkey responsibility for the delivery,
installation and acceptance testing of the tower. In order to develop a complete
and operational system, the points of demarcation between systems and all
contractors is critical to the system implementation process. Therefore, the
Tower Contractor's responsibilities are defined. The Contractor's
Responsibilities listed apply to those commodities and subsystems included in
each approved Site Design Document.

Contractors shall follow good engineering practices in the preparation,
administration, implementation, inspection and acceptance of each individual
subsystem at the designated sites.

The Site Development Contractor shall be the responsible party for site
management and act as the general site manager for all construction and
coordination between

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contractors, vendors and the Commonwealth until Final Site Acceptance by the
Commonwealth. The Contractors shall comply with the following representative
sequence and order of subsystem installations.

B-5.8.1   SHELTER SUBSYSTEM

Tower System contractor shall provide the following items to the Shelter System
contractor per the RFP
          >>      Tower light controller

The Tower System contractor shall install the following equipment into the
shelter per the RFP.
          >>      RJ45 patch blocks for tower alarms

The Tower System contractor shall perform the following electrical connections
in the shelter per the RFP.
          >>      Power wires from tower lights to tower light controller

Tower System contractor shall provide the following information to the Shelter
System contractor per the RFP.
          >>      Electrical loads of all equipment
          >>      Thermal loads of all equipment
          >>      Amount of floor/wall space required
          >>      Floor/wall loading requirement
          >>      Requested location in shelter for equipment

B-5.8.2   GENERATOR SUBSYSTEM

                  - None Required -

B-5.8.3   MICROWAVE SUBSYSTEM

Tower System contractor shall provide the following information to the Microwave
System contractor per the RFP.

          >>      List and description of tower alarms to be interfaced with
                  network management system

B-5.8.4  RADIO SUBSYSTEM

Tower System contractor shall provide the following information to the Radio
System contractor per the RFP.

          >>      List and description of tower alarms to be interfaced with
                  network management system

B-5.8.5   CIVIL CONTRACTOR

                  - None Required -

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B-5.8.6   TOWER SUBSYSTEM

In addition to the previously described tasks, the tower system contractor
responsibilities shall include all required material and labor, and shall be
comprised of, but not be limited to, the following tasks per the RFP.

         PERFORM THE INSTALLATION OF THE FOLLOWING EQUIPMENT ON SITE

          >>      Deliver tower steel to site, offload, and stack and/or store
                  securely

          >>      Erect tower and all related sub-assemblies

          >>      Perform tower ATP

         PERFORM THE FOLLOWING CONNECTIONS TO EXTERIOR GROUND SYSTEM

              SELF-SUPPORTING TOWER CONFIGURATION:

          >>      legs of tower to external ground system

          >>      waveguide/ice bridge to external ground system

              GUYED TOWER CONFIGURATION:

          >>      base of tower to external ground system

          >>      guy anchor ground systems, connected above and below the
                  anchor turnbuckle

          >>      waveguide/ice bridge to external ground system

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B-6      SITE WORK

The Civil Contractor responsibilities, including all required material and labor
shall be comprised of, but not limited to, the following responsibilities and
tasks per the RFP.

SITE WORK REQUIREMENTS AND SPECIFICATIONS

The civil contractor shall provide the installation of the tower foundation,
shelter foundation, generator foundation, fuel tank foundation, grounding, and
all other site related civil construction as outlined the RFP.

Site work requirements will vary considerably based on the initial condition of
the site. Sites will vary from an existing active site requiring limited
modification of the infrastructure to an undeveloped, heavily forested, remote
mountain top location. Therefore, a statement of work for each site shall be
developed and included in the Preliminary Site Plan after the preliminary site
visits have been accomplished

GENERAL CONSTRUCTION REQUIREMENTS

All materials, design, and construction procedures shall be in accordance with
the RFP.

SITE WORK DEFINITIONS

The following section describes the primary work requirements, to be performed
by the Contractor at a typical site. As site specific designs and plans are
defined, the Civil Contractor shall provide a statement of work for each site in
accordance with the specific work tasks and variations in work as defined in the
RFP. The following basic requirements must be tailored in size or capacity to
meet the intent of the functionality and work tasks listed in the RFP.

DEVELOPMENT AND CONSTRUCTION OF:

          >>      Access Road
          >>      Compound Road
          >>      Compound Clearance
          >>      Road Locations
          >>      Road Clearing
          >>      Road Construction
          >>      Road Grading
          >>      Road Drainage
          >>      Bridges, Culverts, and Fords
          >>      Road Maintenance
          >>      Access Road Gates
          >>      Highway Occupancy and Driveway Permits
          >>      Seeding For Road Construction
          >>      Environmental Protection For Road Construction

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          >>      Forest Fire Prevention and Control

B-6.3.1    SITE WORK SUBMITTALS

Civil contractors shall submit the final site work based on the site plan
drawings. The Civil contractor will provide a Site Design Document (SDD) for
each of the sites to be contracted. Civil contractors shall "mark-up" the SDD
drawings for final approval by the Commonwealth prior to any work being started
at a site. These marked-up drawings shall become the site work submittals. To
develop the site, the civil contractor shall use these marked-up and approved
drawings. The civil contractors will utilize the following information for the
development of each site per the RFP.

          >>      Preliminary Site Staking

          >>      Soil Borings

          >>      Soil Test Results

          >>      Final Site Survey

          >>      Preliminary Site Plan

          >>      Site Design Document

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B-7      CIVIL ENGINEERING

The Contractor shall be responsible for the quality and accuracy of all site
design work and civil engineering services. These engineering services shall
include the following items and be supplied to the site development contractor
performing the actual site work. The site contractor shall utilize the following
design documentation to construct the radio sites.

          >>      Land Search
          >>      Preliminary Site Staking
          >>      Soil Borings
          >>      Soil Test Results
          >>      Final Site Visit
          >>      Final Site Survey
          >>      Site Plan

The following items shall be included as part of the Site Design Document per
the RFP.

          >>      Site Survey
          >>      Vicinity Map
          >>      Boundary Map
          >>      Site Elevations
          >>      Compound Layout
          >>      Tower Location (Lat./Long.)
          >>      Access Road Design
          >>      Drainage Design
          >>      Grading Design
          >>      Design Notes
          >>      Include Foundation Designs -Tower, Shelter, Fuel Tank,
                  Generator (provided by other contractors)
          >>      Include Tower Drawings (provided by Tower contractor)
          >>      Include Soil Boring and Test Results
          >>      Utility Access Design

B-7.1.1   PROFESSIONAL ENGINEERING CERTIFICATION

All site-specific drawings and associated design calculations shall bear the
stamp of a Professional Engineer licensed in the Commonwealth of Pennsylvania
when required by state and local authorities. Drawing sets shall be provided to
the Commonwealth by the civil contractor in accordance with Section B.2.

B-7.1.2   TOWER DRAWINGS

A tower drawing package shall be developed by the tower vendor and packaged for
each site. This drawing package shall contain key erection and secondary
drawings as

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described in Section B.5.1. will be provided for the civil contractors review
and understanding.

The drawings shall be supplied on ANSID(24" x 36")size for ease of distribution.
The drawings shall also be supplied in an electronic format suitable for storage
and retrieval. Vendors are to supply all drawings in AutoCAD version 13.

B-7.1.3   KEY TOWER ERECTION DRAWINGS

The key erection drawings shall include but not be limited to the following per
the RFP.

          >>      Site name
          >>      List of all secondary drawings
          >>      Chart of complete antenna/waveguide data
          >>      Elevation View (to include tower member descriptions, assembly
                  and erection details.)
          >>      Guy wire information (Changes in elevation, sizes, etc.)
          >>      A plan view of the tower showing guy wire azimuth,
                  transmission line ladder, climbing ladder and transmission
                  lines

B-7.1.4   SECONDARY TOWER DRAWINGS

Secondary drawings shall include but not limited to the following per the RFP.

          >>      Foundation drawings with all necessary details shown.
          >>      Lighting kit installation.
          >>      Grounding.
          >>      Packing list showing part number, sizes and weights of
                  associates materials.
          >>      Antenna mounting detail.
          >>      Miscellaneous appurtenances installation
          >>      Cable bridge detail

B-7.1.5  DRAWING PACKAGES

When drawing packages are sent to the Commonwealth, the following practices
shall apply.

          >>      Two blue/black line sets shall be issued to the Commonwealth
                  for field construction.
          >>      One reproducible set of drawings will be issues for a
                  permanent record to the Commonwealth upon completion of the
                  project.

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2144 PA Rider B                   Page 43 of 46                   March 22, 2000

<PAGE>

                          Rider B - Statement of Work
--------------------------------------------------------------------------------

B-8      ACCEPTANCE TESTING

The following section defines the types of acceptance testing which will need to
be performed in order to meet the RFP specification and maintain quality control
of the development of the radio sites.

SUBSYSTEM ACCEPTANCE TESTING

The Subsystem Acceptance WBS element collects the effort for the preparation and
conducting site subsystem acceptance tests or other subsystems as required.
Subsystem Acceptance is a combination of analysis, inspect, and demonstrations.
Refer to Rider "H" Acceptance Testing for Subsystem Acceptance Test Procedures.

B-8.1.1   EQUIPMENT SHELTER SUBSYSTEM ACCEPTANCE TESTING

Equipment Shelter Subsystem Tests shall apply to the Equipment Shelter and all
Ancillary Equipment.

B-8.1.2   EMERGENCY GENERATOR SUBSYSTEM ACCEPTANCE TESTING

Emergency Generator Subsystem Tests shall apply to the Emergency Generator and
all Ancillary Equipment.

B-8.1.3   TOWER SUBSYSTEM ACCEPTANCE TESTING

Tower Subsystem Tests shall apply to the Tower and all Ancillary Equipment.

B-8.1.4   SITE WORK SUBSYSTEM ACCEPTANCE TESTING

Site Work Subsystem Tests shall apply to the Site Work and all Ancillary
Equipment.

SUBSYSTEM INTEROPERABILITY ACCEPTANCE TESTING

This WBS element collects the efforts for interoperational verification of all
provided subsystems at a site as defined in Rider "H"- Acceptance Testing.
Quality Inspection Points shall be defined as part of the Acceptance Testing
Plan.

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2144 PA Rider B                   Page 44 of 46                   March 22, 2000

<PAGE>

                          Rider B - Statement of Work
--------------------------------------------------------------------------------

B-9      PROJECT LOGISTICS AND SUPPORT

This WBS element collects the efforts for Project Logistics and Support for site
development as defined in the RFP

INSTALLATION

The Installation WBS element collects the costs and effort associated with
installation of equipment and subsystems at the final site location.

B-9.1.1   INSTALLATION DOCUMENTATION

The Contractor's shall provide a "System As-Built Manual". This manual will
contain equipment model, options, location, installation, interconnection and
electrical level information necessary for complete maintenance and trouble
shooting for each site. The system documentation binders as a minimum shall
conform to the Detailed Design Document procedures and shall contain specific
diagrams with regard to the following:

          >>      Site floor plan, cable tray and equipment rack layouts

          >>      System block diagram

          >>      Equipment programming parameters/templates and jumpering
                  configurations

          >>      Detailed interconnection drawings

          >>      All external equipment inter-cabling, cable and/or wiring,
                  shall be labeled with pre-printed adhesive wire markers.
                  Markers shall be placed at each end, adjacent to the
                  connector, plug or terminus.

          >>      Inventory with serial numbers and equipment references

          >>      Interconnection drawings that show all connections between
                  sub-assemblies, such as terminal boards, panel assemblies or
                  other equipment, to which external connections are made.

          >>      Hardware version numbers

          >>      Numbering and labeling of all interconnecting cabling
                  associated with remote control units

          >>      Numbering and labeling of all connections to modular panels

          >>      Numbering and labeling of all interconnecting cabling between
                  any remote site controllers or processors, alarm circuits, and
                  leased telephone company circuits

          >>      Site level setting block diagrams

          >>      Spare set of cable labels shall be provided in each site "as
                  built" manual

          >>      Theory of Operation and Maintenance Manual for each deployed
                  product

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2144 PA Rider B                   Page 45 of 46                   March 22, 2000

<PAGE>

                          Rider B - Statement of Work
--------------------------------------------------------------------------------

B-9.1.2   INSTALLATION INSPECTIONS

The Acceptance Test Plan as delivered by the Contractor shall include quality
inspection points as provided by the Commonwealth. Each checkpoint shall require
verification by the Commonwealth or its affiliates, before installation efforts
may proceed. The Commonwealth, may at its discretion, accept written
verification from the Contractor that the quality checkpoint was verified by the
Contractor's on-site superintendent, in lieu of the Commonwealth performing the
inspection.

SHIPPING

The Shipping WBS element collects the costs and effort associated with shipment
of equipment and subsystems from the Contractor's facility to the final site
location for installation. The contractor is responsible for the shipping,
unloading and installation of all equipment proposed as defined in the RFP.

TRAINING

Training is the WBS element summarizing the efforts to prepare and present the
training courses as defined in the RFP.

WARRANTY / MAINTENANCE

The Warranty WBS element collects the status of the warranty support which
begins upon total site acceptance by the Commonwealth of Pennsylvania. Refer to
Rider "F" Warranty / Maintenance, of the contract for terms and conditions for
Warranty and Maintenance.

SPARES

The Spares WBS element is the WBS element summarizing the spares for the service
technicians in the field.

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2144 PA Rider B                   Page 46 of 46                   March 22, 2000

<PAGE>

                            RIDER C - Equipment List
-------------------------------------------------------------------------------

                                     [LOGO]

                          COMMONWEALTH OF PENNSYLVANIA

                             ROHN CONSTRUCTION, INC.

                             SITE DEVELOPMENT SYSTEM

                            RIDER C - EQUIPMENT LIST

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2145n PA Rider C                   1 of 9                      October 1, 1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

<TABLE>
<CAPTION>

                                                     RIDER C - TABLE OF CONTENTS

<S>                                                                         <C>
C-1     GENERAL OVERVIEW.....................................................3
C-2     EQUIPMENT SHELTER SYSTEM.............................................4
C-3     EMERGENCY GENERATOR SYSTEM...........................................5
C-4     TOWER SYSTEM.........................................................6
C-5     SITE DEVELOPMENT SERVICES............................................7
C-6     SITE DEVELOPMENT ENGINEERING SERVICES................................8
C-7     EQUIPMENT LIST.......................................................9

</TABLE>

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2145 PA Rider C                     2 of 9                      October 1,1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

C-1      GENERAL OVERVIEW

The purpose of this EQUIPMENT LIST is to identify the various equipment,
products, subsystems (ITEMS) that shall be required for the project. The
Equipment List shall define all Items that can be purchased by the Commonwealth,
Agencies of the Commonwealth, system participants as well as other entities
(local municipalities, counties, etc) able to purchase from the State Contract
5820-06.

The Equipment List shall contain a deliverable which shall fully detail the
specific product model numbers, options, and subsystem assemblies and materials.
These material items shall also contain quantity and pricing. Installation and
other applicable services shall also be defined. All third party equipment shall
be separately priced and the Contractor shall provide optional third party
equipment for the Commonwealth's consideration.

The following Equipment shall be categorized into the following primary
sections:

         Equipment Shelter System
         Emergency Generator System
         Tower System
         Site Development System
         Site Development Engineering System

The Equipment List and pricing considerations are based upon quantities
contained in the PROPOSAL. Equipment and Subsystem prices shall be independently
defined for software, hardware, installation services and 3rd party equipment
and/or services. Item pricing as defined shall be directly available for the
State Purchasing Contract 5820-06. Specific Items may be unavailable for other
entity purchase subject to mutually agreement between the Commonwealth and the
Contractor. The Contractor shall update the equipment list to accommodate
additional equipment and subsystems as required by the Commonwealth or as new
equipment and product lines become available.

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2145 PA Rider C                      3 of 9                    October 1,1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

C-2 EQUIPMENT SHELTER SYSTEM
(Refer to C-7. Pages TBD)
This section details all equipment, product and subsystem items associated with
Equipment shelters. This includes quantity and pricing for materials and
installation as well as any other applicable services. Items include but are not
limited to: AC Power and Electrical Service, UPS System and Battery Bank,
Heating and Air Conditioning, Fire Extinguisher, Shelter Grounding System,
Interior Lighting System, Exterior Lighting System, Cable Ladder Trays, Cable
Entry Ports, Patch Block Mounting Surface, Shelter Foundation Design, Doors -
Locks and Keys, DC Power Plant, Generator Room - Attached and Detached,
Acceptance Testing, Warranty, Maintenance and Support, Shipping and Delivery,
Installation, off-loading, and maintenance documentation and as-built
documentation.

-------------------------------------------------------------------------------
2145 PA Rider C                    4 of 9                     October 1,1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

C-3      EMERGENCY GENERATOR SYSTEM
(Refer to C-7. Pages TBD)
This section details all equipment, product and subsystem items associated with
Emergency Generators. This includes quantity and pricing for materials and
installation as well as any other applicable services. Items include but are not
limited to: Generator Alarms, Patch Blocks, Battery and Charger, Automatic
Transfer Switch, Manual Transfer Switch, Generator Set Control System, Fuel
Tank, Weather Protective Enclosure, Acceptance Testing, Warranty, Maintenance
and Support, Shipping and Delivery, Installation, off-loading, maintenance
documentation and as-built documentation.

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2145 PA Rider C                      5 of 9                 October 1,1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

C-4      TOWER SYSTEM
(Refer to C-7. Pages TBD)
This section details all equipment, product and subsystem items associated with
the tower systems. This includes quantity and pricing for materials and
installation as well as any other applicable services. Items include but are not
limited to: Tower Design, Tower Foundation Design, Transmission Line Cable
Ladder, Waveguide Bridge, Climbing Ladder, Tower Lighting, Microwave Dish Ice
Shields, Tower Painting, Acceptance Testing, Warranty, Maintenance and Support,
Shipping and Delivery, Installation, off-loading, maintenance and as-built
documentation.

-------------------------------------------------------------------------------
2145 PA Rider C                       6 of 9                 October 1,1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

C-5      SITE DEVELOPMENT SERVICES
(Refer to C-7. Pages TBD)
This section details all equipment, product and subsystem Items associated with
the site development services. This includes quantity and pricing for materials
and installation as well as any other applicable services. Items include but are
not limited to: Install Tower Foundation, Install Shelter Foundation, Install
Generator Foundation, Install shelter Ramps, Install Fuel Tank Foundation,
Install Waveguide Bridge Piers, Construct Access Road, Construct Compound Road,
Clearing of Compound Area, Install Electrical and Telephone Pedestal, Install
Drainage, Install Compound Fencing and Gate, Install Fence Grounding, Perfrom
Final Grading, Site Gravelling, Remove Spoils, Excavate and Backfill, Acceptance
Testing, Warranty, Maintenance and Support, Shipping and Delivery, Installation,
Off-loading,. Maintenance and as-built documentation.

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2145 PA Rider C                      7 of 9                     October 1,1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

C-6      SITE DEVELOPMENT ENGINEERING SERVICES
(Refer to C-7. Pages TBD)
This section details all equipment, product and subsystem Items associated with
the site development engineering services. This includes quantity and pricing
for all applicable services. Items include but are not limited to: Land Search,
Preliminary Site Staking, Soil Borings, Soil Testing and Report, Final Site
Visit, Final Site Survey, and Site Plan.

-------------------------------------------------------------------------------
2145 PA Rider C                       8 of 9                   October 1,1999

<PAGE>

                             RIDER C-Equipment List
-------------------------------------------------------------------------------

C-7      EQUIPMENT LIST
(Please refer to attached Equipment List)

-------------------------------------------------------------------------------
2145 PA Rider C                       9 of 9                  October 1,1999

<PAGE>

                         ROHN CONSTRUCTION, INC. RIDER E

                              SCHEDULE OF PAYMENTS

-        100% of engineering costs, by site, at the time of Commonwealth
         acceptance of the Site Design Document.

-        100% of shelter costs, by site, at the time of acceptance by the
         Commonwealth.

-        100% of generator costs, by site, at the time of acceptance by the
         Commonwealth.

-        100% of tower costs, by site, at the time of acceptance by the
         Commonwealth.

-        100% of civil construction costs, by site, upon final acceptance of the
         site by the Commonwealth.

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

                          COMMONWEALTH OF PENNSYLVANIA

                             ROHN CONSTRUCTION, INC.

                            SITE DEVELOPMENT CONTRACT

                              ROHN INDUSTRIES, INC.

                       RIDER F - WARRANTY AND MAINTENANCE

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2147 PA Rider F                    Page 1 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

<TABLE>
<CAPTION>

                                                                                                  TABLE OF CONTENTS
                                                                                                  -----------------

<S>                                                                                                     <C>
F-1   GENERAL OVERVIEW AND REQUIREMENTS..................................................................3

   F-1.1    DEGREES OF FAILURE ON INFRASTRUCTURE EQUIPMENT...............................................3
      F-1.1.1     MAJOR FAILURE..........................................................................3
      F-1.1.2     MINOR FAILURE..........................................................................3
   F-1.2    MALFUNCTIONED EQUIPMENT......................................................................3
   F-1.3    PREVENTATIVE MAINTENANCE.....................................................................3
   F-1.4    TEST EQUIPMENT CALIBRATION...................................................................4
   F-1.5    GUARANTEES (MATERIAL AND LABOR)..............................................................4
   F-1.6    SYSTEM WARRANTY AND SYSTEM MAINTENANCE PERFORMANCE REPORTS...................................4
   F-1.7    CENTRALIZED SUPPORT ORGANIZATION (CSO).......................................................4

F-2   STANDARD WARRANTY TERMS............................................................................5

   F-2.1    ON-SITE WARRANTY.............................................................................6

F-3   COMMENCEMENT OF WARRANTY...........................................................................7

   F-3.1    WARRANTY -SITE FACILITY......................................................................7

F-4   SHELTER SYSTEM WARRANTY............................................................................8

   F-4.1    2 YEAR WARRANTY..............................................................................8
   F-4.2    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (24 HR COVERAGE).......................8
   F-4.3    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (NON 24HR COVERAGE)....................9

F-5   EMERGENCY GENERATOR SYSTEM........................................................................11

   F-5.1    2 YEAR WARRANTY.............................................................................11
   F-5.2    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (24 HR COVERAGE)).....................11
   F-5.3    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (NON 24HR COVERAGE)...................12

F-6   TOWER SYSTEM......................................................................................13

   F-6.1    10 YEAR WARRANTY............................................................................13
   F-6.2    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (24 HR COVERAGE)......................13
   F-6.3    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (NON 24HR COVERAGE)...................14

F-7   SITE WORK.........................................................................................15

   F-7.1    5 YEAR WARRANTY.............................................................................15
   F-7.2    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (24 HR COVERAGE)......................15
   F-7.3    EXTENDED WARRANTY AND MAINTENANCE -3 ADDITIONAL YEARS (NON 24HR COVERAGE)...................16

</TABLE>

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2147 PA Rider F                    Page 2 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-1      GENERAL OVERVIEW AND REQUIREMENTS

The purpose of this document is to define the Warranty and Maintenance Support
System that shall be provided by the Contractor to ensure the reliability of the
Statewide-Integrated Voice and Data System (IV&D) being purchased by the
Commonwealth as it pertains to the Site Development RFP # 1998-SD-1.

This Warranty shall pertain specifically to all material, labor and services as
purchased in accordance with this contract and based upon the Site Development
RFP that called for the purchase of Shelter System, Emergency Generator System,
Tower System and Site Work.

F-1.1    DEGREES OF FAILURE ON INFRASTRUCTURE EQUIPMENT

The following defines two categories of failure. Major and Minor failures shall
have different response and restoration times as described below.

F-1.1.1       MAJOR FAILURE

Any failure that results in a loss of voice or data service, a complete
outage or reduction of System capacity, that are not restored by hot standby or
fault tolerant Equipment, shall constitute a major failure. All major failures
require immediate service as stipulated by the response and repair times
associated with the various Equipment types outlined in this document.

F-1.1.2       MINOR FAILURE

Any failure that generates a concern or alarm of any nature other
than major, as defined above, shall be deemed a minor failure. All minor
failures must be cleared during the course of the normal workday on which they
occur. In the event a minor failure occurs after hours, on a weekend or holiday,
as defined in Rider B, shall be repaired during the next normal working day.

F-1.2    MALFUNCTIONED EQUIPMENT

Malfunctions that cannot be immediately or unequivocally diagnosed and
pinpointed to a certain item of Equipment or service shall require the
participation of all service suppliers until responsibility for the problem
has been established. In no instance shall the failure to resolve the issue
of responsibility relieve any of the suppliers of the mutual obligation to
restore System operability with the least impact on the availability of the
System to the end users.

F-1.3    PREVENTATIVE MAINTENANCE

Contractor shall provide preventative maintenance on all Equipment as specified
in order to be compliant with the response times as indicated in this rider. In
addition Rider B (Statement of Work) shall further define the Preventive
Maintenance Plan and the

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2147 PA Rider F                    Page 3 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

Schedule as a specific deliverable. A complete description of preventive
maintenance shall specify the frequency of preventive maintenance required for
all proposed Equipment and Systems. Preventive maintenance shall be performed
according to a schedule that is mutually acceptable to the Commonwealth and
Contractor. The schedule shall be consistent with the operation requirements of
the Commonwealth and shall be based upon the specific needs of the Equipment
being maintained.

F-1.4    TEST EQUIPMENT CALIBRATION

All test equipment utilized for installation, warranty and
maintenance on the Statewide-Integrated Voice and Data System shall be
calibrated as recommended by the Equipment manufacture(s) and traceable to the
National Bureau of Standards. The Contractor Program Manager must maintain
certificates of calibration.

F-1.5    GUARANTEES (MATERIAL AND LABOR)

Contractor guarantees that all Equipment supplied pursuant to this RFP will be
new and of first quality throughout. All replaced parts or Equipment will become
property of the Commonwealth.

F-1.6    SYSTEM WARRANTY AND SYSTEM MAINTENANCE PERFORMANCE REPORTS

Contractor shall furnish the Commonwealth with a monthly report of all warranty
and maintenance requests. As a minimum the following data is required:

          / /      Date and time of arrival on Site
          / /      Description of malfunction reported
          / /      Diagnosis of failure and work performed
          / /      Date and time failure was corrected
          / /      Charges for service, if applicable
          / /      Name of person performing service
          / /      All preventative maintenance results

F-1.7    CENTRALIZED SUPPORT ORGANIZATION (CSO)

Due to the vastness of the system being implemented, the vendor shall list the
locations and functionally of each in-state and out-of-state service center(s).
The Contractor shall open a Centralized Support Organization (CSO). This
facility shall report directly to the Contractor Project Manager and interface
with the Commonwealth via the Radio Project Office. This center shall provide
Warranty Services, be capable of receiving repair calls and dispatching service
personnel to meet response times on a 24-hour, 365-day basis. Contractor shall
provide a SINGLE toll-free telephone number for all maintenance, repair and
emergency service requirements. The CSO shall remain in effect from the
beginning of the Contract until the end of the optional System Maintenance
period selected by the Commonwealth.

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2147 PA Rider F                    Page 4 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-2      STANDARD WARRANTY TERMS

Warranty shall be defined as the standard Contractor Warranty Terms, as
indicated below.

                         CONTRACTOR'S STANDARD WARRANTY

Contractor warrants for a period of twenty-four (24) months from the date of
completion and acceptance of a site commodity that the Equipment will be free
from defects in material and workmanship and will be in conformity with
applicable specifications and drawings (the "Specifications"); provided,
however, that this warranty shall not apply to any Equipment which shall have
been abused or misused physically or electrically, or on which the trademark
shall have been defaced or obliterated. Buyer shall request written return
material authorization within the warranty period prior to the return of any
nonconforming Equipment. If Equipment is found not in conformance with this
warranty, it will be covered by this warranty only if written authorization is
requested within a period of twenty-four (24) months from the date of
commencement.

Authorization for return must be secured from Contractor and will not commit
Contractor to the making of any repair or replacement hereunder. Requests for
return authorization should list types and quantities of Equipment involved, the
reason for the request, information concerning operating conditions involved,
and the period of use. In addition, the Order number and, where possible, the
original invoice number covering the original purchase of the Equipment involved
must be shown. Returned Equipment must be shipped, and transportation prepaid,
by the most practical method of shipment. Shipping costs will be credited to the
Buyer for all Equipment found to be not in compliance with this warranty.
Excessive transportation costs will not be allowed. Contractor can accept no
billing for packing, inspection, labor charges or other incidental costs in
connection with any Equipment returned. Unless otherwise requested by Buyer,
returned Equipment found not subject to this warranty will be sent back to
Buyer, transportation collect. In all cases, Contractor's determination will be
final. With respect to Equipment found not in conformity with this warranty, the
remedy will take the form, at Contractor's option, of a replacement or repair of
the defective or nonconforming Equipment.

In the event that it is uneconomical to replace or repair warranted Equipment,
Contractor may, at its sole option, remit the dollar equivalent based upon the
original Equipment sales price and said remittance will be calculated by
applying the pro rata percentage of the unexpired warranty to the original
Equipment sales price. Seller makes no representation or warranty, express,
implied (including but not limited to warranties of merchantability and fitness
for particular purposes), statutory, or related to "Year 2000" matters, other
than the foregoing express warranty. THIS WARRANTY IS IN LIEU OF ALL OTHER
WARRANTIES WHETHER WRITTEN, ORAL, EXPRESS OR IMPLIED (INCLUDING, WITHOUT
LIMITING THE GENERALITY OF THE FOREGOING, ANY WARRANTY OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE). IN NO EVENT WILL CONTRACTOR BE

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2147 PA Rider F                    Page 5 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

LIABLE FOR INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING FROM
BREACH OF THIS WARRANTY, EVEN IF CONTRACTOR HAS BEEN ADVISED OF THE
POSSIBILITIES OF SUCH DAMAGES. THE FOREGOING CONSTITUTES BUYER'S SOLE REMEDY AND
CONTRACTOR'S SOLE LIABILITY FOR BREACH OF WARRANTY. In the event of replacement
pursuant to the foregoing warranty, such warranty shall apply to the replaced
product.

F-2.1    ON-SITE WARRANTY

In the event that warranted Equipment must be repaired on-site, the Contractor
shall provide the necessary material and trained personnel to repair and make
right all items in a professional and proper manner.

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2147 PA Rider F                    Page 6 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-3      COMMENCEMENT OF WARRANTY

Warranty shall begin upon completion and acceptance of work on a specific
commodity at a site. The definition of work and acceptance is further defined in
Riders B (Statement of Work) and Rider H (Acceptance Testing).

F-3.1    WARRANTY - SITE FACILITY

Infrastructure Equipment shall be defined as Equipment supporting the
development of a "site". This will include the Shelter System, the Emergency
Generator System, the Tower System and the Site Work. This shall be further
defined as the "Site Facilities".

Warranty shall be defined as agreement(s) between the Contractor and the
Commonwealth for using the supplied Site Facility. All such agreements shall be
paid for and managed by the Commonwealth through the Radio Project Office (RPO).
This type of agreement would allow for specific response and repair times during
the Warranty period on Equipment purchased directly by the Commonwealth.
Contractor shall provide pricing on all Warranty Equipment listed in Rider C
(Equipment List and Charges).

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2147 PA Rider F                    Page 7 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-4      SHELTER SYSTEM WARRANTY

The following section defines the Warranty for the Shelter System.

F-4.1    2 YEAR WARRANTY

This (2)-two year Warranty shall provide on-site service by a factory authorized
service provider.

The coverage includes repair or replacement of any defective equipment, system
hardware and software that is initially delivered defective or becomes defective
through normal wear and usage.

All batteries shall be warranted for a period of TEN YEARS from date of system
acceptance.

COVERAGE - 24 HR. BY 7 DAYS

         8 hour response, 4 hour repair
               Roof
               Electrical System
               HVAC
               Lights - Internal and External
               UPS to Include Batteries and Charger (Batteries 10 year warranty)
               DC Power Plant (Batteries 10 warranty)
               Alarms
               Fire Extinguishers

         24 hour response, 2 day repair
               Walls
               Doors
               All Seals
               Foundations
               Floors
               Cable Trays
               Entrance Ports
               Internal Grounding

F-4.2    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (24 HR COVERAGE)

This (3)-three-year extended Warranty shall provide on-site service by a factory
authorized service provider. This package will include maintenance of all items
installed. This maintenance will follow the manufacturer's maintenance
guidelines at the manufacturer's recommended periodicity.

This coverage includes any defective equipment that becomes defective through
normal wear and usage.

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2147 PA Rider F                    Page 8 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

COVERAGE - 24 HR. BY 7 DAYS

         8 hour response, 4 hour repair
               Roof
               HVAC
               UPS to Include Batteries and Charger (Batteries 10 year warranty)
               DC Power Plant (Batteries 10 warranty)
               Alarms
               Fire Extinguishers

         24 hour response, 2 day repair
               Walls
               Doors
               All Seals
               Floors

F-4.3    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (NON 24HR
COVERAGE)

This (3)-three-year extended Warranty for non-24 hour coverage shall provide
on-site service by a factory authorized service provider. This is an optional
package, which the Commonwealth shall evaluate and determine its value prior to
contracting services from the contractor.

This package will include maintenance of all items installed. This maintenance
will follow the manufacturer's maintenance guidelines at the manufacturer's
recommended periodicity.

The coverage includes any defective equipment that becomes defective through
normal wear and usage.

COVERAGE - 8 HR. BY 5 DAYS

         8 hour response, 8 hour repair
                  Roof
                  Electrical System
                  HVAC
                  Lights - Internal and External
                  UPS to Include Batteries and Charger (Batteries 10 year
                  warranty)
                  DC Power Plant (Batteries 10 warranty)
                  Alarms
                  Fire Extinguishers

         24 hour response, 2 day repair
                  Walls
                  Doors

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2147 PA Rider F                    Page 9 of 16                  October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

                  All Seals
                  Foundations
                  Floors
                  Cable Trays
                  Entrance Ports
                  Internal Grounding

--------------------------------------------------------------------------------
2147 PA Rider F                    Page 10 of 16                 October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-5      EMERGENCY GENERATOR SYSTEM

The following section defines the Warranty for the Emergency Generator System.

F-5.1    2 YEAR WARRANTY

This (2)-two year Warranty shall provide on-site service by a factory authorized
service provider.

The coverage includes repair or replacement of any defective equipment, system
hardware and software that is initially delivered defective or becomes defective
through normal wear and usage.

All batteries shall be warranted for a period of TEN YEARS from date of system
acceptance.

COVERAGE - 24 HR. BY 7 DAYS

         2 hour response, 4 hour repair
                  Emergency Generator and Controls
                  Emergency Generator Transfer Switch
                  Emergency Generator Batteries and Charger (Batteries Warranty
                  for 10 years)
                  Fuel Tank

F-5.2    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (24 HR
COVERAGE)

This (3)-three-year extended Warranty shall provide on-site service by a factory
authorized service provider. This package will include maintenance of all items
installed. This maintenance will follow the manufacturer's maintenance
guidelines at the manufacturer's recommended periodicity.

This coverage includes any defective equipment that becomes defective through
normal wear and usage.

COVERAGE - 24 HR. BY 7 DAYS

         8 hour response, 4 hour repair
                  Emergency Generator and Controls
                  Emergency Generator Transfer Switch
                  Emergency Generator Batteries and Charger (Batteries Warranty
                  for 10 years)
                  Fuel Tank

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2147 PA Rider F                    Page 11 of 16                 October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-5.3    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (NON 24HR
COVERAGE)

This (3)-three-year extended Warranty for non-24 hour coverage shall provide
on-site service by a factory authorized service provider. This is an optional
package, which the Commonwealth shall evaluate and determine its value prior to
contracting services from the contractor.

This package will include maintenance of all items installed. This maintenance
will follow the manufacturer's maintenance guidelines at the manufacturer's
recommended periodicity.

The coverage includes any defective equipment that becomes defective through
normal wear and usage.

COVERAGE - 8 HR. BY 5 DAYS

         8 hour response, 8 hour repair
                  Emergency Generator and Controls
                  Emergency Generator Transfer Switch
                  Emergency Generator Batteries and Charger (Batteries Warranty
                  for 10 years)
                  Fuel Tank

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2147 PA Rider F                    Page 12 of 16                 October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-6      TOWER SYSTEM

The following section defines the Warranty for the Tower System.

F-6.1    10 YEAR WARRANTY

This (10)-ten year Warranty shall provide on-site service by a factory
authorized service provider.

All lighting and controls shall be warranted for a period of TWO YEARS from date
of system acceptance.

The coverage includes repair or replacement of any defective equipment, system
hardware and software that is initially delivered defective or becomes defective
through normal wear and usage.

COVERAGE - 24 HR. BY 7 DAYS (FIRST TWO YEARS)

         8 hour response, 4 hour repair
                  Tower
                  Cable Ladder
                  Waveguide Bridge
                  Lighting and Controls (Two Year Warranty)

         24 hour response, 2 day repair
                  Climbing Ladder

COVERAGE - 8 HR. BY 5 DAYS (YEAR THREE THROUGH YEAR TEN)

         8 hour response, 4 hour repair
                  Tower
                  Cable Ladder
                  Waveguide Bridge

         24 hour response, 2 day repair
                  Climbing Ladder

F-6.2    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (24 HR COVERAGE)

This (3)-three-year extended Warranty shall provide on-site service by a factory
authorized service provider. This package will include maintenance of all items
installed. This maintenance will follow the manufacturer's maintenance
guidelines at the manufacturer's recommended periodicity.

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2147 PA Rider F                    Page 13 of 16                 October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

This coverage includes any defective equipment that becomes defective through
normal wear and usage.

COVERAGE - 24 HR. BY 7 DAYS

         8 hour response, 4 hour repair
                  Lighting and Controls

F-6.3    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (NON 24HR
COVERAGE)

This (3)-three-year extended Warranty for non-24 hour coverage shall provide
on-site service by a factory authorized service provider. This is an optional
package, which the Commonwealth shall evaluate and determine its value prior to
contracting services from the contractor.

This package will include maintenance of all items installed. This maintenance
will follow the manufacturer's maintenance guidelines at the manufacturer's
recommended periodicity.

The coverage includes any defective equipment that becomes defective through
normal wear and usage.

COVERAGE - 8 HR. BY 5 DAYS

         8 hour response, 8 hour repair
                  Lighting and Controls

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2147 PA Rider F                    Page 14 of 16                 October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

F-7      SITE WORK

The following section defines the Warranty for the Site Work.

F-7.1    5 YEAR WARRANTY

This (5)-five year Warranty provides on-site service by an authorized service
contractor.

The coverage includes any defectives in civil construction materials and
workmanship.

This Warranty excludes vegetation growth and acts of God.

COVERAGE - 24 HR. BY 7 DAYS

         24 hour response, 24 hour repair
                  Tower Foundation
                  Shelter Foundation
                  Generator Foundation
                  Fuel Tank Foundation
                  Compound Construction (All related construction at the
                  compound)
                  Access Road Construction (All related construction of the
                  access road)
                  Site Grounding
                  Utility Construction
                  Fence Construction

F-7.2    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (24 HR COVERAGE)

This (3)-three year extended Warranty provides on-site service by an authorized
service contractor.

The coverage includes any defectives in civil construction materials and
workmanship.

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2147 PA Rider F                    Page 15 of 16                 October 1, 1999

<PAGE>

                       RIDER F - WARRANTY AND MAINTENANCE
--------------------------------------------------------------------------------

This Warranty excludes vegetation growth and acts of God.

COVERAGE - 24 HR. BY 7 DAYS

         24 hour response, 24 hour repair
                  Tower Foundation
                  Shelter Foundation
                  Generator Foundation
                  Fuel Tank Foundation
                  Compound Construction (All related construction at the
                  compound)
                  Access Road Construction (All related construction of the
                  access road)
                  Site Grounding
                  Utility Construction
                  Fence Construction

F-7.3    EXTENDED WARRANTY AND MAINTENANCE - 3 ADDITIONAL YEARS (NON 24HR
COVERAGE)

This (3)-three year extended Warranty for non-24hr provides on-site service by
an authorized service contractor.

The coverage includes any defectives in civil construction materials and
workmanship.

This Warranty excludes vegetation growth and acts of God.

COVERAGE - 8 HR. BY 5 DAYS

         24 hour response, 24 hour repair
                  Tower Foundation
                  Shelter Foundation
                  Generator Foundation
                  Fuel Tank Foundation
                  Compound Construction (All related construction at the
                  compound)
                  Access Road Construction (All related construction of the
                  access road)
                  Site Grounding
                  Utility Construction
                  Fence Construction

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2147 PA Rider F                    Page 16 of 16                 October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

                          COMMONWEALTH OF PENNSYLVANIA

                             ROHN CONSTRUCTION, INC.

                             SITE DEVELOPMENT SYSTEM

                          RIDER H - ACCEPTANCE TESTING

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2148 PA Rider H                       1 of 8                     October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

<TABLE>
<CAPTION>

                                                                                        RIDER H - TABLE OF CONTENTS
                                                                                        ---------------------------
<S>                                                                                                     <C>
H-1     GENERAL OVERVIEW.................................................................................3

   H-1.1     SUBSYSTEM ACCEPTANCE TESTING................................................................3
   H-1.2     SUBSYSTEM INTEROPERABILITY ACCEPTANCE TESTING...............................................4

H-2     SUBSYSTEM ACCEPTANCE TESTING.....................................................................5

   H-2.1     EQUIPMENT SHELTER SUBSYSTEM TESTS...........................................................5
     H-2.2.1      SHELTER CONSTRUCTION VERIFICATION......................................................5
     H-2.2.2      SHELTER INSTALLATION VERIFICATION......................................................5
     H-2.2.3      SHELTER GROUND SUBSYSTEMS VERIFICATION.................................................5
     H-2.2.4      PROVIDED ANCILLARY EQUIPMENT VERIFICATION..............................................5
     H-2.2.5      SHELTER ELECTRICAL SUBSYSTEMS VERIFICATION.............................................5
     H-2.2.6      HVAC SUBSYSTEMS VERIFICATION...........................................................5
     H-2.2.7      ALARM SUBSYSTEMS VERIFICATION..........................................................6
   H-2.2     EMERGENCY GENERATOR SUBSYSTEM TESTS.........................................................6
     H-2.2.1      EMERGENCY GENERATOR INSTALLATION VERIFICATION..........................................6
     H-2.2.2      EMERGENCY GENERATOR SUBSYSTEM..........................................................6
     H-2.2.3      AUTOMATIC TRANSFER SWITCH..............................................................6
     H-2.2.4      MANUAL TRANSFER SWITCH.................................................................6
   H-2.3     TOWER SUBSYSTEM TESTS.......................................................................6
     H-2.3.1      TOWER INSTALLATION VERIFICATION........................................................6
     H-2.3.2      TOWER SUBSYSTEM TESTS..................................................................6
     H-2.3.3      FOUNDATION SUBSYSTEM TESTS.............................................................7
   H-2.4     SITE WORK SUBSYSTEM TESTS...................................................................7
     H-2.4.1      SITE WORK INSTALLATION VERIFICATION....................................................7
     H-2.4.2      ACCESS ROAD SUBSYSTEM TESTS............................................................7
     H-2.4.3      SITE SUBSYSTEM TESTS...................................................................7
     H-2.4.4      FOUNDATION SUBSYSTEM TESTS.............................................................7
     H-2.4.5      GROUNDING SUBSYSTEM TESTS..............................................................7
     H-2.4.6      FENCING SUBSYSTEM TESTS................................................................7

H-3     SUBSYSTEM INTEROPERABILITY ACCEPTANCE TESTING....................................................8

</TABLE>

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2148 PA Rider H                       2 of 8                     October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

H-1      GENERAL OVERVIEW

The purpose of the ACCEPTANCE TESTING is to demonstrate performance compliance
of all equipment, subsystems and system designs supplied by the Contractor as
required by the Contract. An Acceptance Test Plan Document (ATP) shall be
delivered within 30 days that details the testing procedures, processes and
performance criteria. The ATP shall contain a set of subsystem and system tests,
performance criteria, and installation standards as referenced in the RFP, the
Contractor's proposal, the Contract and Contract Riders. The criteria detailed
in the ATP shall be mutually agreed to between the Commonwealth and the
Contractor. This mutual agreement shall be documented as a result of the
Contractor submitting and the Commonwealth approving the ATP Deliverable. All
acceptance tests and installation verifications contained in the ATP shall be
performed by the Contractor and verified by the Commonwealth. These tests shall
provide verification compliance of equipment and system performance based upon
the RFP specifications and Rider B deliverables.

The ATP shall fully detail the specific tests and procedures as well as the time
and materials required for each test to be performed as part of the deployment
schedule. Quality control inspections shall insure that installations have been
completed in compliance with the methods and techniques specified in the RFP and
Statement of Work (Rider B.

The following test categories shall be defined and performed:

H-1.1     SUBSYSTEM ACCEPTANCE TESTING

Subsystem Acceptance Testing shall apply to the individual subsystem and its
ancillary equipment to include the following:

EQUIPMENT SHELTER SUBSYSTEM TESTS
Equipment Shelter Subsystem Tests shall apply to the Equipment Shelter and all
Ancillary Equipment.

EMERGENCY GENERATOR SUBSYSTEM TESTS
Emergency Generator Subsystem Tests shall apply to the Emergency Generator and
all Ancillary Equipment.

TOWER SUBSYSTEM TESTS
Tower Subsystem Tests shall apply to the Tower and all Ancillary Equipment.

SITE WORK SUBSYSTEM TESTS
Site Work Subsystem Tests shall apply to the Site Work and all Ancillary
Equipment.

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2148 PA Rider H                       3 of 8                     October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

H-1.2    SUBSYSTEM INTEROPERABILITY ACCEPTANCE TESTING

Subsystem Interoperability Acceptance Tests shall apply to the interoperability
of all provided subsystems.

The test procedures shall be completed, agreed upon and delivered within the
first 30 days from the date of a signed contract between the Commonwealth and
the Contractor. Any omissions of this Rider or the Contract shall yield to the
most rigorous requirements of RFP, its addenda, the PROPOSAL, or the Statement
of Work and Deliverables (Rider B).

The Commonwealth shall be notified 48 hours in advance of the Contractor
conducting any subsystem and system level tests. The Commonwealth or its
authorized representative(s) will monitor any or all testing, and performance or
installation verifications deemed appropriate. Regardless of the Commonwealth or
its authorized representative(s) presence, the Contractor shall document in
writing, the outcome of all testing and verifications listed in the ATP. Failure
of a test shall require re-testing at no expense to the Commonwealth. The
Commonwealth reserves the right to disapprove any test(s), test procedure(s), or
test result(s), which deviate from the approved test procedures. It shall be the
sole responsibility of the Contractor to remedy any such disapproved tests to
the satisfaction of, and at no additional cost to, the Commonwealth.

The results of the tests and the associated Punch List of outstanding items to
be compiled or re-tested shall be signed by the representatives of both the
Commonwealth and the Equipment Shelter Contractor and forwarded to the
Commonwealth for review and acceptance. The outstanding items shall be resolved
within seven (7) working days and these items shall be retested. If the
outstanding items have an effect on other previously performed tests then
re-testing shall also be required.

The system equipment shall be accurately measured with commonly available test
equipment, instruments and tools. The specific items of test equipment required
shall be listed in the ATP. Appropriate amount of test equipment shall be made
available to accommodate concurrent testing processes. All test equipment and
tools, designated for testing or other support functions shall be calibrated by
a Precision Measurement Equipment Laboratory within the valid calibration
period.

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2148 PA Rider H                       4 of 8                     October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

H-2      SUBSYSTEM ACCEPTANCE TESTING

This section shall categorize the deliverable of Subsystem Acceptance Testing.
Subsystem Acceptance Testing shall be performed on all equipment provided by the
Contractor at each site. All Subsystem Acceptance Testing shall be completed
prior to the Contractor receiving Final Site Acceptance.

H-2.1    EQUIPMENT SHELTER SUBSYSTEM TESTS

This section shall categorize the deliverable of the Equipment
Shelter System Tests. Equipment Shelter System Tests shall provide functional
performance verification of the Equipment Shelter System and provided Ancillary
equipment. This documentation shall be supplied as part of the Detailed Design
Document as described in Rider B. The tests to be performed shall include, but
not be limited to, the following items:

H-2.2.1     SHELTER CONSTRUCTION VERIFICATION

This section shall contain detailed information that defines
particular Field Tests to be performed to verify that the Equipment Shelter
meets the construction requirements of the RFP.

H-2.2.2     SHELTER INSTALLATION VERIFICATION

This section shall contain detailed information that defines
particular Field Tests to be performed to verify that the Equipment Shelter was
installed in a manner consistent with the requirements of the RFP.

H-2.2.3     SHELTER GROUND SUBSYSTEMS VERIFICATION

 This section shall contain detailed
information that defines particular Field Tests to be performed to verify that
the Shelter Ground Subsystems meet the requirements of the RFP.

H-2.2.4     PROVIDED ANCILLARY EQUIPMENT VERIFICATION

 This section shall contain detailed information
that defines particular Field Tests to be performed to verify that the Provided
Ancillary Equipment meets the requirements of the RFP.

H-2.2.5     SHELTER ELECTRICAL SUBSYSTEMS VERIFICATION

This section shall contain detailed
information that defines particular Field Tests to be performed to verify that
the Shelter Electrical Subsystems meets the requirements of the RFP.

H-2.2.6     HVAC SUBSYSTEMS VERIFICATION

This section shall contain detailed information
that defines particular Field Tests to be performed to verify that the HVAC
Subsystems meets the requirements of the RFP.

--------------------------------------------------------------------------------
2148 PA Rider H                       5 of 8                     October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

H-2.2.7     ALARM SUBSYSTEMS VERIFICATION

 This section shall contain detailed information that defines
particular Field Tests to be performed to verify that the Alarm Subsystems meets
the requirements of the RFP.

H-2.2       EMERGENCY GENERATOR SUBSYSTEM TESTS

This section shall categorize the deliverable of the Emergency Generator System
Tests. Emergency Generator System Tests shall provide functional performance
verification of the Emergency Generator System and provided Ancillary equipment.
This documentation shall be supplied as part of the Detailed Design Document.
The tests to be performed shall include, but not be limited to, the following
items:

H-2.2.1     EMERGENCY GENERATOR INSTALLATION VERIFICATION

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Emergency Generator and provided
Ancillary Equipment were installed in a manner consistent with the requirements
of the RFP.

H-2.2.2     EMERGENCY GENERATOR SUBSYSTEM

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Emergency Generator Subsystems meets
the requirements of the RFP.

H-2.2.3     AUTOMATIC TRANSFER SWITCH

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Automatic Transfer Switch meets the
requirements of the RFP.

H-2.2.4     MANUAL TRANSFER SWITCH

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Manual Transfer Switch meets the
requirements of the RFP.

H-2.3   TOWER SUBSYSTEM TESTS

This section shall categorize the deliverable of the Tower System Tests. Tower
System Tests shall provide functional performance verification of the Tower
System and provided Ancillary equipment. This documentation shall be supplied as
part of the Detailed Design Document. The tests to be performed shall include,
but not be limited to, the following items:

H-2.3.1     TOWER INSTALLATION VERIFICATION

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Tower and provided Ancillary Equipment
were installed in a manner consistent with the requirements of the RFP.

H-2.3.2 TOWER SUBSYSTEM TESTS

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Tower Subsystems meets the requirements
of the RFP.

--------------------------------------------------------------------------------
2148 PA Rider H                       6 of 8                     October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

H-2.3.3     FOUNDATION SUBSYSTEM TESTS

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Foundation Subsystems meets the
requirements of the RFP.

H-2.4       SITE WORK SUBSYSTEM TESTS

This section shall categorize the deliverable of Site Work System Tests. Site
Work System Tests shall provide functional performance verification of
subsystems deployed at final site location(s). Deployed Subsystem Tests shall be
completed on applicable subsystems prior to commencement of Final System
Acceptance Tests. This documentation shall be supplied as part of the Detailed
Design Document. The tests to be performed shall include, but not be limited to,
the following items:

H-2.4.1     SITE WORK INSTALLATION VERIFICATION

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Site Work Systems were installed in a
manner consistent with the requirements of the RFP.

H-2.4.2     ACCESS ROAD SUBSYSTEM TESTS

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Access Road Subsystems meets the
requirements of the RFP.

H-2.4.3     SITE SUBSYSTEM TESTS

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Site Subsystems meets the requirements
of the RFP.

H-2.4.4     FOUNDATION SUBSYSTEM TESTS

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Foundation Subsystems meets the
requirements of the RFP.

H-2.4.5     GROUNDING SUBSYSTEM TESTS

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Grounding Subsystems meets the
requirements of the RFP.

H-2.4.6     FENCING SUBSYSTEM TESTS

This section shall contain detailed information that defines particular Field
Tests to be performed to verify that the Fencing Subsystems meets the
requirements of the RFP.

--------------------------------------------------------------------------------
2148 PA Rider H                       7 of 8                     October 1, 1999

<PAGE>

                          RIDER H - Acceptance Testing
--------------------------------------------------------------------------------

H-3      SUBSYSTEM INTEROPERABILITY ACCEPTANCE TESTING

This section shall categorize the deliverable of Subsystem Interoperability
Acceptance Testing. Subsystem Interoperability Acceptance Testing shall be
performed to verify the interoperability of all subsystems provided by the
Contractor at each site by verification of Quality Inspection Points (QIP). All
Subsystem Interoperability Acceptance Testing shall be performed to verify that
all provided subsystems meet the specified design/implementation requirements.
The following Quality Inspection Points shall be included as part of the
verification process during Acceptance Testing. These QIPs, at a minimum, shall
be included in the ATP.

          >>       Foundation Steel Installed
          >>       Concrete Slump Test and Pour
          >>       Back Fill Around Foundations
          >>       Grounding System Installed
          >>       Concrete Cure Strength Test (7day)
          >>       Power Connection to Tower for Aviation  Warning Lights
          >>       All Shelter Systems Inspected and Tested
          >>       Generator Power Connected to Shelter and Tested
          >>       Final Grade of Site
          >>       Fencing and Gate Connected to Site Ground System
          >>       Acceptance Inspection of Site
          >>       Final Acceptance Inspection

--------------------------------------------------------------------------------
2148 PA Rider H                       8 of 8                     October 1, 1999

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