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                                                                    EXHIBIT 4-AH







                       REMARKETING AND CONTINGENT PURCHASE
                                    AGREEMENT



                                      among



                             HERCULES INCORPORATED,


                                HERCULES TRUST V


                                       and


                         BANC OF AMERICA SECURITIES LLC



                          Dated as of February 9, 2000
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                  REMARKETING AND CONTINGENT PURCHASE AGREEMENT

     REMARKETING AND CONTINGENT PURCHASE AGREEMENT dated as of February 9, 2000
by and among Hercules Incorporated, a Delaware corporation (the "COMPANY"),
Hercules Trust V, a Delaware statutory business trust (the "TRUST"), and Banc of
America Securities LLC, as remarketing agent (the "REMARKETING AGENT").

                                   WITNESSETH:

         WHEREAS, the Trust has issued 200,000 Auction Rate Reset Preferred
Securities (the "PREFERRED SECURITIES") in an aggregate stated liquidation
amount of $200,000,000 and 6,200 Auction Rate Reset Common Securities (the
"COMMON SECURITIES", and together with the Preferred Securities, the "TRUST
SECURITIES") in an aggregate stated liquidation amount of $6,200,000 under the
Amended and Restated Trust Agreement dated as of November 12, 1998 among the
Company, the Administrative Trustees, the Delaware Trustee and the Property
Trustee (as the same has been and may be amended from time to time, the "TRUST
AGREEMENT");

         WHEREAS, the sole assets of the Trust consist of $206,200,000 aggregate
principal amount of Auction Rate Reset Junior Subordinated Notes Series A (the
"SUBORDINATED NOTES") of the Company purchased by the Trust from the Company
with the proceeds of the sale of the Trust Securities;

         WHEREAS, at the request of the Holders of a Majority in Liquidation
Amount of the Trust Securities, the Preferred Securities (or, following the
distribution of Subordinated Notes to Holders of Preferred Securities upon the
dissolution of the Trust, the Subordinated Notes) may be remarketed in
accordance with the terms hereof;

         WHEREAS, the Company and the Trust have requested that Banc of America
Securities LLC ("BAS") act as the Remarketing Agent and, as such, perform the
duties described herein; and

         WHEREAS, BAS is willing to act as Remarketing Agent and, as such, to
perform such duties on the terms and conditions expressly set forth herein;

         NOW, THEREFORE, in consideration of the covenants herein made, and
subject to the conditions herein set forth, the parties hereto agree as follows:

         SECTION 1. Definitions. Capitalized terms used and not defined in this
Agreement shall have the meanings assigned to them in the Trust Agreement. In
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addition, as used in this Agreement, the following terms shall have the
following definitions:

         "1934 ACT REPORTS" has the meaning set forth in Section 2(b)(iv).

         "AFFILIATED BIDDER" has the meaning set forth in Section 5(b).

         "ASSOCIATED PERSON" has the meaning set forth in Article 1(ee) of the
ByLaws of the National Association of Securities Dealers, Inc.

         "BAS" has the meaning set forth in the fourth recital hereto.

         "BID" means an irrevocable offer to purchase the aggregate outstanding
Liquidation Amount of Preferred Securities at the Remarketing Price or,
following any distribution of Subordinated Notes to Holders, the aggregate
outstanding principal amount of such Subordinated Notes, as the case may be,
with a Distribution Rate or interest rate, as applicable, equal to the Bid Rate
specified in such Bid and with a redemption date or maturity date, as the case
may be, on the Remarketed Redemption Date.

         "BID RATE" means the proposed Distribution Rate on the Preferred
Securities and/or interest rate on Subordinated Notes specified in a Bid.

         "BUSINESS DAY" means any day other than a Saturday, Sunday or other day
on which banking institutions in The City of New York or London are authorized
or required by law, regulation or executive order to close.

         "CHANGE OF CONTROL" shall be deemed to have occurred if (i) any Person
or group of Persons (within the meaning of Section 13 or 14 of the Exchange Act)
shall have acquired beneficial ownership (within the meaning of Rule 13d-3 of
the Exchange Act) of 30% or more of the Voting Stock of the Company or (ii)
Continuing Directors shall cease to be a majority of the members of the Board of
Directors of the Company.

         "COMMISSION" means the Securities and Exchange Commission.

         "COMPANY" has the meaning set forth in the initial paragraph hereto.

         "CONTINUING DIRECTORS" means (i) the members of the Board of Directors
of the Company on the date hereof and (ii) future members of such Board of
Directors who were nominated or appointed by a majority of the Continuing
Directors at the date of their nomination or appointment.

         "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended.


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         "EXCHANGE ACT REGULATIONS" means the rules and regulations promulgated
under the Exchange Act.

         "EXPECTED RESET DATE" has the meaning set forth in Section 5(a)(i).

         "FAILED REMARKETING" means an event deemed to have occurred if,
following the giving of notice by the Requesting Holders to the Remarketing
Agent as contemplated by Section 5(a)(i), the settlement of a purchase and sale
of the Preferred Securities (or, if applicable, the Subordinated Notes) shall
not have occurred within the applicable time limit specified in this Agreement
and in any event if such a settlement shall not have occurred by the 23rd
Business Day following the delivery of the related Remarketing Notice, giving
effect, if applicable, to the provisions of Section 7.

         "FINAL RESET DATE" has the meaning set forth in Section 5(a)(ii).

         "FORMER HOLDERS" has the meaning set forth in Section 5(i).

         "GUARANTEE AGREEMENT" means the Preferred Securities Guarantee
Agreement dated as of November 12, 1998, executed by the Company for the benefit
of Holders of the Preferred Securities, as amended, supplemented, modified or
superseded from time to time.

         "INDENTURE" means the Indenture (the "BASE INDENTURE") dated as of
November 12, 1998 between the Company and The Chase Manhattan Bank, as Indenture
Trustee, as supplemented by a First Supplemental Indenture dated as of November
12, 1998, a Second Supplemental Indenture dated as of July 6, 1999, a Third
Supplemental Indenture dated as of October 25, 1999, a Fifth Supplemental
Indenture dated as of January 24, 2000 and a Sixth Supplemental Indenture dated
as of February 9, 2000 and as further amended, supplemented, modified or
superceded from time to time.

         "INDENTURE TRUSTEE" means the Trustee pursuant to the Indenture.

         "INVESTMENT COMPANY ACT" means the Investment Company Act of 1940, as
amended.

         "MATERIAL ADVERSE CHANGE" means any development that could reasonably
be expected to result in a material adverse change in the business, properties
or financial condition of the Company and its subsidiaries, taken as a whole.

         "OFFERING MEMORANDUM" has the meaning set forth in Section 12.


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         "PREFERRED SECURITIES" has the meaning set forth in the first recital
hereto.

         "REFERENCE CORPORATE DEALER" means a leading dealer of publicly traded
debt securities selected by the Company, which dealer shall be a Qualified
Institutional Buyer (as defined in Rule 144A under the Securities Act).

         "REMARKETED REDEMPTION DATE" means the later of (i) the first
anniversary of the Remarketing Settlement Date on which Replacement Securities
are issued and (ii) February 9, 2002.

         "REMARKETING" means a remarketing of Preferred Securities or
Subordinated Notes pursuant to Section 5.

         "REMARKETING NOTICE" has the meaning set forth in Section 5(a)(i).

         "REMARKETING PRICE" means (i) with respect to the Preferred Securities,
a price equal to 100% of the aggregate outstanding Liquidation Amount of the
Preferred Securities and (ii) with respect to the Subordinated Notes, a price
equal to 100% of the aggregate outstanding principal amount of the Subordinated
Notes.

         "REMARKETING SETTLEMENT DATE" means the third Business Day immediately
following the Reset Date.

         "RENEWED REMARKETING" has the meaning set forth in Section 7.

         "REPLACEMENT PREFERRED SECURITIES" has the meaning set forth in Section
5(j).

         "REPLACEMENT SECURITIES" has the meaning set forth in Section 5(j).

         "REPLACEMENT SUBORDINATED NOTES" has the meaning set forth in Section
5(j).

         "REPRESENTATION DATE" has the meaning set forth in Section 2(a).

         "REQUESTING HOLDERS" has the meaning set forth in Section 5(a)(i).

         "RESET DATE" means any date established as a Reset Date pursuant to
Section 5.

         "RESET RATE" means the Winning Bid Rate.

         "SECONDARY PURCHASE AGREEMENT" means an agreement to be dated as of the
Reset Date (or such other date permitted by applicable law) among the


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Company, the Trust, the Remarketing Agent and the Secondary Purchaser providing
for the purchase of the Preferred Securities, or the Subordinated Notes, as the
case may be, by the Secondary Purchaser, in a form customary for transactions of
this type and as otherwise agreed among the Company, the Trust, the Remarketing
Agent and the Secondary Purchaser.

         "SECONDARY PURCHASER" has the meaning set forth in Section 5(c).

         "SECURITIES ACT" means the Securities Act of 1933, as amended.

         "SUBORDINATED NOTES" has the meaning set forth in the second recital
hereto.

         "TRANSACTION DOCUMENTS" means this Agreement, the Purchase Agreement,
the Trust Agreement, the Guarantee Agreement, the Indenture, the Common
Securities, the Secondary Purchase Agreement, the Preferred Securities and the
Subordinated Notes; provided that for any representation made as of the date
hereof pursuant to Section 2(b), Transaction Documents means this Agreement, the
Purchase Agreement, the Trust Agreement, the Guarantee Agreement, the Indenture,
the Common Securities, the Letter Agreement, the Preferred Securities and the
Subordinated Notes.

         "TRUST" has the meaning set forth in the initial paragraph hereto.

         "TRUST AGREEMENT" has the meaning set forth in the initial paragraph
hereto.

         "TRUST SECURITIES" has the meaning set forth in the first recital
hereto.

         "WINNING BID RATE" has the meaning set forth in Section 5(b).

         "VOTING STOCK" means capital stock of the Company having ordinary
voting power for the election of directors.

         SECTION 2. Representations and Warranties. (a) Basic Warranties. Each
of the Company and the Trust, on the one hand, and the Remarketing Agent, on the
other hand, represents and warrants to the other as of the date hereof, the
Reset Date and the Remarketing Settlement Date (each of the foregoing dates
being hereinafter referred to as a "REPRESENTATION DATE") that:

                  (i) Status. It is a duly and validly existing entity under the
         laws of the jurisdiction of its creation, formation or incorporation
         and, if relevant under such laws, in good standing.


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                  (ii) Powers. It has the corporate or trust power and authority
         to execute, enter into and perform its obligations under, or
         contemplated under, this Agreement and consummate the transactions
         contemplated hereby.

                  (iii) No Violation or Conflict. The execution, delivery and
         performance by such party of this Agreement, the consummation of the
         transactions herein contemplated and compliance by such party with its
         obligations hereunder (A) do not violate or conflict with (1) any
         provision of its organizational documents, (2) any law applicable to
         it, any order or judgment of any court or other agency of government
         applicable to it or any of its assets that affects the legality,
         validity or enforceability of this Agreement and (B) do not and will
         not conflict with or constitute a breach of any contractual restriction
         binding on or affecting it or any of its assets.

                  (iv) Consents. All governmental and other consents that are
         required to have been obtained by it with respect to the performance by
         such party of its obligations under this Agreement have been obtained
         and are in full force and effect and all conditions of any such
         consents have been complied with.

                  (v) Obligations Binding. Its obligations under this Agreement
         constitute its legal, valid and binding obligations, enforceable
         against it in accordance with the terms of this Agreement, except as of
         the enforcement hereof may be limited by bankruptcy, insolvency,
         reorganization, moratorium or other laws of general application
         relating to or affecting the enforcement of creditors' rights or by
         general equitable principles.

                  (vi) Absence of Litigation. There is not pending or, to the
         best of its knowledge, threatened against or affecting it or any of its
         Affiliates any action, suit or proceeding at law or in equity or before
         any court, tribunal, governmental body, agency or official or any
         arbitrator that could reasonably be expected to materially and
         adversely affect the legality, validity or enforceability against it of
         this Agreement or its ability to perform its obligations under this
         Agreement.

                  (vii) Non-Reliance. It is acting for its own account, and it
         has made its own independent decision to enter into this Agreement and
         as to whether this Agreement is appropriate or proper for it based upon
         its own judgment and upon advice from such advisers as it has deemed
         necessary. It is not relying on any communication (written or oral) of
         any other party as investment advice or as a recommendation to enter
         into this Agreement, it being understood that information and
         explanations related to the terms and conditions of this Agreement
         shall not be considered investment


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         advice or a recommendation to enter into this Agreement. No
         communication (written or oral) received from any other party shall be
         deemed to be an assurance or guarantee as to the expected results of
         this Agreement. No other party is acting as a fiduciary for or an
         adviser to it with respect to this Agreement.

                  (viii) Assessment and Understanding. It is capable of
         assessing the merits of and understanding (on its own behalf or through
         independent professional advice), and understands and accepts, the
         terms, conditions and risks of this Agreement. It is also capable of
         assuming, and assumes, the risks of this Agreement.

         (b) Representations and Warranties of the Company and the Trust. Each
of the Company and the Trust further represents and warrants to the Remarketing
Agent as of each Representation Date, as applicable to each such entity, that:

                  (i) Securities Validly Issued. The Preferred Securities and
         Subordinated Notes have been, and the Replacement Preferred Securities
         and the Replacement Subordinated Notes will be, validly authorized and
         executed by the Trust and the Company, as the case may be, and
         authenticated, issued and delivered in the manner provided for in the
         Trust Agreement and the Indenture, as the case may be, and delivered
         against payment of the purchase price therefor as provided in the
         Purchase Agreement, and constitute, or will constitute, legally binding
         obligations of the Trust or the Company, as the case may be, entitled
         to the benefits of the Trust Agreement and Indenture.

                  (ii) No Event of Default. No Event of Default under the Trust
         Agreement and no Event of Default under the Indenture has occurred and
         is continuing and no such event or circumstance would occur as a result
         of its entering into or performing its obligations under this
         Agreement.

                  (iii) Compliance with Exchange Act Requirements. The Company
         has made all the filings with the Commission that it is required to
         make under the Exchange Act and the Exchange Act Regulations, and each
         such filing complies in all material respects with the requirements of
         the Exchange Act and Exchange Act Regulations.

                  (iv) No Material Misstatements. The Company's most recent
         Annual Report on Form 10-K, and its Quarterly Reports on Form 10-Q and
         Current Reports on Form 8-K filed after the end of the fiscal year to
         which such Annual Report relates (collectively, the "1934 ACT
         REPORTS"), as supplemented by material press releases, at the time they
         were filed did


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         not, and, after giving effect to the transactions contemplated by the
         Transaction Documents do not, contain any untrue statement of a
         material fact or omit to state a material fact necessary in order to
         make the statements therein, in the light of the circumstances under
         which they were made, not misleading.

                  (v) No Material Adverse Change. Since the respective dates as
         of which information is given in the 1934 Act Reports, except as
         otherwise stated therein, or as supplemented by material press
         releases, there has been no Material Adverse Change.

                  (vi) Not an Investment Company. Neither the Company nor the
         Trust is an "investment company" or an entity "controlled" by an
         "investment company" as such terms are defined in the Investment
         Company Act.

         SECTION 3.  Covenants.  (a) The Company hereby covenants with the
Remarketing Agent as follows:

                  (i) Maintain Authorizations. The Company shall use all
         reasonable efforts to maintain in full force and effect all consents of
         any governmental or other authority that are required to be obtained by
         it with respect to this Agreement and shall use all reasonable efforts
         to obtain any such consents that may become necessary in the future.

                  (ii) Comply with Laws. The Company shall comply in all
         material respects with all applicable laws and orders to which it may
         be subject if failure so to comply would materially impair its ability
         to perform its obligations under this Agreement.

                  (iii) Furnish Documentation. The Company will furnish to the
         Remarketing Agent: (i) unless available to the Remarketing Agent on
         EDGAR or the Company's website, each document filed after the date
         hereof by the Company pursuant to the periodic reporting requirements
         of the Exchange Act and (ii) in connection with the Remarketing of the
         Preferred Securities or Subordinated Notes, as the case may be, such
         other information as the Remarketing Agent may reasonably request from
         time to time. Notwithstanding the foregoing sentence, the Company
         agrees to provide the Remarketing Agent with as many copies of the
         foregoing written materials and other Company-approved information as
         the Remarketing Agent may reasonably request for use in connection with
         the Remarketing of the Preferred Securities or Subordinated Notes, as
         the case may be, and consents to the use thereof for such purpose.


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                  (iv) Notification. If, at any time prior to the Remarketing
         Settlement Date, any event or condition known to the Company relating
         to or affecting the Company, the Preferred Securities or the
         Subordinated Notes shall occur that could reasonably be expected to
         cause any of the reports, documents, materials or information referred
         to in Section 3(a)(iii) or any document incorporated therein by
         reference to contain an untrue statement of a material fact or omit to
         state a material fact, the Company shall promptly notify the
         Remarketing Agent in writing of the then-known circumstances and
         details of such event or condition.

                  (v) Comply with Securities Laws. The Company will comply with
         the Securities Act and the rules and regulations of the Commission
         thereunder, the Exchange Act and the Exchange Act Regulations so as to
         permit the completion of the Remarketing of the Preferred Securities or
         Subordinated Notes, as the case may be, as contemplated in this
         Agreement.

                  (vi) No Purchase of Securities. The Company agrees that
         neither it nor any of its subsidiaries or Affiliates shall purchase or
         otherwise acquire, or enter into any agreement to purchase or otherwise
         acquire, any of the Preferred Securities or Subordinated Notes prior to
         the Remarketing thereof by the Remarketing Agent, other than pursuant
         to this Agreement.

                  (vii) Notification of Rating Agency Action. The Company will
         provide prompt notice by telephone, confirmed in writing (which may
         include facsimile or other electronic transmission), to the Remarketing
         Agent of any notification or announcement by a "nationally recognized
         statistical rating organization" (as defined by the Commission for
         purposes of Rule 436(g)(2) under the Securities Act) with regard to a
         downgrade to below investment grade or withdrawal of the rating of any
         security of the Company or the placement on what is currently called a
         "watch list"or a "credit watch" with negative implications of any
         security of the Company.

                  (viii) Restriction on Debt Issuance. During the period
         commencing on the date on which the Company receives a Remarketing
         Notice in accordance with Section 5(a)(i) and ending on the earlier of
         (A) the date of the related Remarketing Settlement Date or (B) the date
         of the related Failed Remarketing, the Company will not, without the
         consent of the Remarketing Agent, offer, sell or contract to sell, or
         otherwise dispose of, directly or indirectly, or announce the offering
         of, any debt securities with a maturity of more than one year but fewer
         than two years.

                  (ix) Best Efforts. The Company shall use its best efforts to
         assist the Remarketing Agent in Remarketing the Preferred Securities or
         the


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         Subordinated Notes, as the case may be, in the manner contemplated by
         this Agreement.

          (b) The Remarketing Agent hereby covenants with the Company as
follows:

                  (i) Maintain Authorizations. The Remarketing Agent will use
         all of its reasonable efforts to maintain in full force and effect all
         consents of any governmental or other authority that are required to be
         obtained by it with respect to this Agreement and shall use all
         reasonable efforts to obtain any that may become necessary in the
         future.

                  (ii) Comply with Laws. The Remarketing Agent shall comply in
         all material respects with all applicable laws and orders which it may
         be subject if failure so to comply would materially impair its ability
         to perform its obligations under this Agreement.

         SECTION 4. Appointment and Obligations of Remarketing Agent and
Calculation Agent; Secondary Purchaser. (a) The Company and the Trust hereby
appoint BAS as Remarketing Agent and as Calculation Agent under the Trust
Agreement and the Indenture (i) to determine, in accordance with the terms
described in Section 5(b), the Reset Rate that, when applied to the Preferred
Securities (or, following the distribution of the Subordinated Notes to Holders
of the Preferred Securities upon dissolution of the Trust, the Subordinated
Notes), shall result in the resale of all outstanding Preferred Securities (or,
if applicable, all outstanding Subordinated Notes), at a sales price equal to
the Remarketing Price; provided that the Reset Rate shall in no event exceed the
rate permitted by applicable law, (ii) to conduct a private auction of all
outstanding Preferred Securities or Subordinated Notes, as the case may be, in
accordance with Section 5 of this Agreement, and (iii) to enter into a Secondary
Purchase Agreement with respect to the Preferred Securities or the Subordinated
Notes, as the case may be.

          (b) Pursuant to the Secondary Purchase Agreement, the Secondary
Purchaser, either as the sole purchaser or as the representative of a syndicate
of purchasers designated by the Secondary Purchaser, shall agree, subject to the
terms and conditions set forth therein, that the Secondary Purchaser and any
such other purchasers shall purchase such Preferred Securities or Subordinated
Notes, as the case may be, from the holders thereof at a price equal to the
Remarketing Price.

         SECTION 5.  Determination of Reset Date; Remarketing Procedures.

          (a) (i) Subject to Section 7, the Holders of a Majority in Liquidation
Amount of the Trust Securities (or, if applicable, the holders of a majority in


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principal amount of the Subordinated Notes), acting together as a single class
(the "REQUESTING HOLDERS"), have the right to require Remarketing of the Trust
Securities (or, if applicable, the Subordinated Notes) at any time. The
Requesting Holders may exercise this right by delivering a written notice to the
Remarketing Agent at any time requesting a Remarketing of the Preferred
Securities (or, if applicable, the Subordinated Notes). Upon the receipt of such
notice, the Remarketing Agent shall immediately deliver a written notice to the
Company on behalf of the Requesting Holders (the "REMARKETING NOTICE"). If the
Requesting Holders exercise their right to require the Remarketing of the
Preferred Securities (or, if applicable, the Subordinated Notes), the Reset Date
shall be the sixth Business Day after the date on which the Remarketing Notice
is received by the Company (the "EXPECTED RESET DATE").

                  (ii) Notwithstanding Section 5(a)(i):

                           (A) the Company may, by notice to the Remarketing
                  Agent, direct that the Reset Date be delayed if the Company
                  believes it will be unable to meet the conditions to
                  Remarketing in the absence of such a delay; and


                           (B) the Remarketing Agent may, by notice to the
                  Company, direct that the Reset Date be delayed if the
                  Remarketing Agent believes that a Remarketing will not be
                  successful in the absence of such a delay;

         provided that the Company and the Remarketing Agent, in either such
         event, will use their reasonable best efforts to establish a delayed
         Reset Date that is within five Business Days after the Expected Reset
         Date, but in no event later than the 15th Business Day following the
         date on which the related Remarketing Notice was received, or the 20th
         Business Day in the case of a Renewed Remarketing to which the
         provisions of Section 7 apply (as applicable, the "FINAL RESET DATE").

                  (iii) If the Company and the Remarketing Agent have not
         agreed, on or prior to the sixth Business Day preceding the Final Reset
         Date, to a Reset Date that is not later than the Final Reset Date, a
         Failed Remarketing shall be deemed to have occurred.

                  (iv) Notwithstanding the provisions of this Section 5, upon
         receipt of a Remarketing Notice the Company shall have the right, in
         its sole discretion, to elect to pay the aggregate Liquidation Amount
         of and accumulated and unpaid Distributions on the Preferred Securities
         (or the outstanding principal of and accrued and unpaid interest on the


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         Subordinated Notes, as the case may be), rather than proceed with the
         Remarketing. The Company shall make such election by sending written
         notice, within five Business Days after the receipt of the Remarketing
         Notice, to the Remarketing Agent and the Trustee. If the Company makes
         such election, it shall pay the aggregate Liquidation Amount of and
         accumulated and unpaid Distributions on the Preferred Securities (or
         the outstanding principal of and accrued and unpaid interest on the
         Subordinated Notes, as the case may be) to the Holders thereof on the
         date eight Business Days after receipt of the Remarketing Notice.

          (b) The Company shall, by notice to the Remarketing Agent no later
than five Business Days prior to the Reset Date, select and specify three
Reference Corporate Dealers. By 3:00 p.m., New York City time, on the Reset
Date, the Remarketing Agent shall request Bids from such Reference Corporate
Dealers. The Remarketing Agent or an Affiliate or Associated Person thereof (any
such person, an "AFFILIATED BIDDER") may, at its option, enter a Bid. The
Remarketing Agent shall disclose to the Company the Bids obtained and determine
the lowest Bid Rate (the "WINNING BID RATE") from among the Bids obtained on the
Reset Date. By approximately 4:30 p.m., New York City time, on the Reset Date,
the Remarketing Agent shall notify the Company, the Indenture Trustee and the
Property Trustee of the Winning Bid Rate. If on a Reset Date, Bids are not
submitted by at least two Reference Corporate Dealers, or if the lowest Bid
submitted would result in a Winning Bid Rate in excess of the rate permitted by
applicable law, the Remarketing shall be deemed to be a Failed Remarketing on
the corresponding Remarketing Settlement Date. The Winning Bid Rate determined
by the Remarketing Agent, absent manifest error, shall be binding and conclusive
upon the Holders of the Trust Securities, the holders of the Subordinated Notes,
the Company and the Trust.

         (c) On the Reset Date, the Remarketing Agent shall designate as the
Secondary Purchaser (the "SECONDARY PURCHASER") the Reference Corporate Dealer
providing the Bid containing the Winning Bid Rate. If the Winning Bid Rate is
specified in the Bids submitted by two or more bidders, the Remarketing Agent
shall, in consultation with the Company, designate one of such bidders as
the Secondary Purchaser.

          (d) On the Reset Date, the Secondary Purchaser shall enter into a
Secondary Purchase Agreement for the purchase by such Secondary Purchaser at the
Remarketing Price of the aggregate Liquidation Amount of Preferred Securities,
with (i) a Distribution Rate equal to the Winning Bid Rate (or, if Subordinated
Notes shall have been distributed to Holders of the Trust Securities, the
aggregate principal amount of Subordinated Notes with an interest rate equal to
the Winning Bid Rate) and (ii) a Mandatory Redemption Date (or, in the case of
Subordinated Notes, a maturity date) on the Remarketed Redemption Date.


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          (e) If a Remarketing shall have occurred pursuant to this Section 5
but settlement of the purchase and sale of the Preferred Securities or
Subordinated Notes, as the case may be, does not occur on the corresponding
Remarketing Settlement Date, then, unless the provisions of Section 7 with
respect to a Renewed Remarketing shall apply, a Failed Remarketing shall be
deemed to have occurred on such Remarketing Settlement Date.

          (f) At the time and in the manner specified in the Secondary Purchase
Agreement, the Secondary Purchaser shall pay on the Remarketing Settlement Date
to the Remarketing Agent on behalf of the holders of the Preferred Securities or
Subordinated Notes, as the case may be, an amount of cash equal to the
Remarketing Price.

          (g) Unless otherwise agreed among the Remarketing Agent, the Paying
Agent (under the Trust Agreement or Indenture, as applicable) and any Former
Holder, the Remarketing Agent shall promptly pay the Remarketing Price to the
Paying Agent, acting solely as agent for the Former Holders, and the Paying
Agent shall pay such amount to the Former Holders on the Remarketing Settlement
Date in the manner specified in the Trust Agreement or the Indenture, as the
case may be. Any amounts held by the Paying Agent for payment to the Former
Holders shall not be property of the Trust or the Company, as the case may be.

          (h) The obligation of the Remarketing Agent to make payment to the
Former Holders in connection with the Remarketing shall be limited to the extent
that the Secondary Purchaser has delivered the Remarketing Price therefor to the
Remarketing Agent.

          (i) Any outstanding Preferred Securities (or, if applicable, the
Subordinated Notes) purchased on the Remarketing Settlement Date shall be deemed
to be transferred to the Secondary Purchaser and shall be replaced in the manner
provided in Section 5(j). After the Remarketing Settlement Date (except in the
event of (y) a Failed Remarketing or (z) a failure by the Trust to pay on the
Remarketing Settlement Date all accrued and unpaid Distributions (including any
Additional Distributions) to such Remarketing Settlement Date (or, in the case
of the Subordinated Notes, a failure by the Company to pay on the Remarketing
Settlement Date all accrued interest (including any Additional Interest) on the
Subordinated Notes to such Remarketing Settlement Date)), (A) the Trust (or the
Company, in the case of the Subordinated Notes) shall make no further payments
to, and the Trust (or the Company, in the case of the Subordinated Notes) shall
have no further obligations under the Trust Agreement (or the Indenture, in the
case of the Subordinated Notes) in respect of, the holders of such replaced
securities (the "FORMER HOLDERS"), (B) the Trust (or the Company, in the case of


                                       13
<PAGE>   15
the Subordinated Notes) shall only be obligated to make payments to the holders
of Replacement Securities and (C) the Preferred Securities (or, if applicable,
the Subordinated Notes) of the Former Holders shall no longer represent an
obligation of, or interest in, the Trust (or the Company, in the case of the
Subordinated Notes) but shall only represent a right to receive the proceeds of
the Remarketing from the Paying Agent under the Trust Agreement or the
Indenture, as the case may be.

         (j) (i) The Company shall cause replacement certificates evidencing the
remarketed Preferred Securities (the "REPLACEMENT PREFERRED SECURITIES") to be
executed by an Administrative Trustee on behalf of the Trust and authenticated
by the Property Trustee and (ii) the Subordinated Note Issuer shall cause
replacement certificates evidencing the Subordinated Notes (the "REPLACEMENT
SUBORDINATED NOTES", and together with the Replacement Preferred Securities, the
"REPLACEMENT SECURITIES") to be executed by an authorized signatory and
authenticated by the Indenture Trustee, in each case, in accordance with the
provisions of this Section 5. If the Preferred Securities are to be purchased on
the Remarketing Settlement Date, (A) the Replacement Preferred Securities shall
be delivered to the purchaser of the remarketed Preferred Securities in
accordance with the terms of the Secondary Purchase Agreement and (B) the
Replacement Subordinated Notes shall be delivered to the Property Trustee of the
Trust. If the Subordinated Notes are to be purchased on the Remarketing
Settlement Date, the Replacement Subordinated Notes shall be delivered to the
purchaser of the remarketed Subordinated Notes in accordance with the terms of
the Secondary Purchase Agreement.

         SECTION 6. Reset of Distribution Rate, Mandatory Redemption Date,
Interest Rate and Maturity Date. From and including the Remarketing Settlement
Date on which Replacement Securities are issued, (a) the Distribution Rate on
the Trust Securities and the Interest Rate on the Subordinated Notes shall be
the Winning Bid Rate and (b) the Mandatory Redemption Date and the maturity date
of the Subordinated Notes shall be the Remarketed Redemption Date.

         SECTION 7. Renewed Remarketing. If a Remarketing has occurred pursuant
to Section 5 that would be a Failed Remarketing pursuant to Section 5(e),
because the purchase and sale of the Preferred Securities (or, if applicable,
the Subordinated Notes) do not take place on the corresponding Remarketing
Settlement Date, and the reason for such failure shall, in the good faith
determination of the Remarketing Agent, result from facts or circumstances that
are not due to the action or inaction of the Company, then the provisions of
Section 5 shall apply to a second remarketing (a "RENEWED REMARKETING") of the
Preferred Securities (or, if applicable, the Subordinated Notes), except that
the Expected Reset Date shall be the sixth Business Day following such
corresponding Remarketing Settlement Date; provided that only one Renewed


                                       14
<PAGE>   16
Remarketing may occur pursuant to this Section 7, and no Renewed Remarketing
shall occur after the Final Reset Date.

         SECTION 8. Failed Remarketing; Contingent Purchase Obligation. The
Remarketing Agent shall give notice of any Failed Remarketing on the date such
Failed Remarketing occurs, or is deemed to have occurred, by 4:00 p.m., New York
City time, to the Company, the Subordinated Note Issuer, the Property Trustee,
the Indenture Trustee and the Paying Agent under the Indenture. In the case of
(i) any Failed Remarketing or (ii) a Change of Control, the Holders of a
Majority in Liquidation Amount of the Trust Securities (or, if applicable, the
holders of a majority in principal amount of the Subordinated Notes) may, by
notice in writing to the Company, which notice, in the case of a Failed
Remarketing, shall be given not later than 15 days after the occurrence of such
Failed Remarketing, require the Company to purchase from the holders thereof, on
a Pro Rata basis in accordance with Section 9 of Annex I to the Trust Agreement,
all outstanding Trust Securities (or, if applicable, all outstanding
Subordinated Notes) for a purchase price equal to the aggregate Liquidation
Amount of such Trust Securities plus accrued but unpaid Distributions thereon
(or, if applicable, the aggregate principal amount of such Subordinated Notes
plus accrued but unpaid interest thereon). Payment of such purchase price shall
be made directly to each such holder on the tenth Business Day following the
date of the notice to the Company pursuant to the preceding sentence. Such
purchase shall be without recourse of any kind to any such holder. The parties
recognize that the occurrence of a Failed Remarketing indicates that it would
not be commercially reasonable under the circumstances to require Holders of
Trust Securities (or, if applicable, holders of the Subordinated Notes) to
attempt to resell such securities otherwise than pursuant to this Section 8, and
that therefore in the event of any default by the Company in its obligations
under this Section 8, a holder shall be entitled to recover the price of the
securities specified herein.

         SECTION 9. Senior Obligations. The obligations of the Company hereunder
constitute senior unsecured obligations, and shall rank pari passu with all
other senior unsecured obligations of the Company. Such obligations are not
subject to, and shall not be affected by, the provisions of Article 10 of the
Base Indenture.

         SECTION 10.  Replacement and Resignation of Remarketing Agent.  (a) The
Company shall not have the right to replace BAS as the Remarketing Agent,
except in the case of bad faith, gross negligence or willful misconduct by BAS.

          (b) BAS may resign at any time for good reason (after consultation
with the Company) and, subject to the following sentence, shall be discharged
from its duties and obligations hereunder or as Calculation Agent under the
Trust Agreement and the Indenture by giving no less than 10 days' notice. Any
such


                                       15
<PAGE>   17
resignation shall become effective upon the Company's appointment of a successor
to perform the services that would otherwise be performed hereunder by the
Remarketing Agent or the Calculation Agent under the Trust Agreement and the
Indenture, as the case may be, and the agreement of any such successor so to
serve. Upon receiving notice from the Remarketing Agent that it wishes to resign
hereunder or as Calculation Agent under the Trust Agreement and the Indenture
stating the reasons for such resignation, the Company shall appoint such a
successor and enter into a new remarketing agreement with it as soon as
reasonably practicable.

          (c) This Agreement shall terminate as to any Remarketing Agent that is
replaced on the effective date of its replacement pursuant to Section 10(b).
Notwithstanding any such termination, the obligations of the Company set forth
in Section 14 shall survive and remain in full force and effect until all
amounts payable under said Section 14 shall have been paid in full.

         SECTION 11. Dealing in the Securities. BAS, when acting as Remarketing
Agent hereunder or under the Secondary Purchase Agreement or when acting in its
individual or any other capacity, may, to the extent permitted by law, buy,
sell, hold or deal in any of the Preferred Securities or Subordinated Notes. The
Remarketing Agent may exercise any vote or join in any action with respect to
any Preferred Securities or Subordinated Notes owned by it with like effect as
if it did not act in any capacity hereunder. BAS, in its individual capacity,
either as principal or agent, may also engage in or have an interest in any
financial or other transaction with the Company as freely as if it did not act
in any capacity hereunder.

         SECTION 12. Offering Memorandum. Promptly following its receipt of a
Remarketing Notice pursuant to Section 5(a)(i), the Company shall furnish an
offering memorandum (the "OFFERING MEMORANDUM") to the Remarketing Agent, in
form and substance reasonably satisfactory to the Remarketing Agent, to be used
in the remarketing by the Secondary Purchaser or purchasers under the Secondary
Purchase Agreement, and shall pay all expenses relating to the preparation and
furnishing of such Offering Memorandum.

         SECTION 13. Conditions to the Remarketing Agent's Obligations. (a) The
obligations of the Remarketing Agent, the Secondary Purchaser and any other
purchasers to perform their respective obligations hereunder and under the
Secondary Purchase Agreement shall be subject to the terms and conditions of the
Secondary Purchase Agreement.

          (b) If at any time during the term of this Agreement, any Event of
Default under the Indenture or any Event of Default under the Trust Agreement,
or event that with the passage of time or the giving of notice or both would


                                       16
<PAGE>   18
become an Event of Default under the Indenture or an Event of Default under the
Trust Agreement, has occurred and is continuing under the Indenture or the Trust
Agreement, then the obligations and duties of the Remarketing Agent under this
Agreement shall be suspended until such default or event has been cured. The
Trust shall cause the Property Trustee to provide to the Remarketing Agent
notice of all such defaults and events of which the Property Trustee is aware
and the Company shall cause the Indenture Trustee to provide to the Remarketing
Agent notice of all such defaults and events of which the Indenture Trustee is
aware.

         SECTION 14. Indemnification. The Company shall indemnify and hold
harmless the Remarketing Agent and its officers and employees from and against
all actions, claims, damages, liabilities and losses, and costs and expenses
related thereto (including reasonable legal fees and costs) relating to or
arising out of actions or omissions in any capacity hereunder and in any
capacity as Calculation Agent under the Trust Agreement and the Indenture,
except actions, claims, damages, liabilities, losses, costs and expenses to the
extent caused by (a) the bad faith, gross negligence or wilful misconduct of
such indemnified party or (b) the breach by the Remarketing Agent of its
representations, warranties and covenants hereunder. This Section 14 shall
survive the termination of the Agreement, the Trust Agreement, the Indenture and
the payment in full of all obligations under the Preferred Securities or the
Subordinated Notes, as the case may be, and this Agreement, whether by purchase,
repurchase, redemption or otherwise.

         SECTION 15. Remarketing Agent's Performance: Duty of Care; Power of
Attorney. The duties and obligations of the Remarketing Agent hereunder shall be
determined solely by the express provisions of this Agreement and the Secondary
Purchase Agreement.

         The Remarketing Agent hereby accepts the obligation set forth in the
Trust Agreement and the Indenture to act as attorney-in-fact for the holders of
the Preferred Securities or Subordinated Notes, as the case may be.

         SECTION 16. Expenses. The Company shall pay the reasonable fees and
disbursements of the Remarketing Agent's counsel incurred in connection with any
Remarketing, including any Renewed Remarketing and any Failed Remarketing and
the Company shall pay the reasonable fees, expenses and disbursements of the
Remarketing Agent and its counsel in connection with the execution and delivery
of the Secondary Purchase Agreement.

         SECTION 17.  Governing Law.  This Agreement shall be governed by and
construed in accordance with the laws of the State of New York without reference
to the choice of law rules thereof.


                                       17
<PAGE>   19
         SECTION 18. Term of Agreement. Unless otherwise terminated in
accordance with the provisions hereof and except as otherwise provided herein,
this Agreement shall remain in full force and effect from the date hereof until
30 days after the earlier of (i) the date all Preferred Securities (or, if
applicable, Subordinated Notes) shall have been redeemed or purchased pursuant
to Section 8 hereof and (ii) the Reset Date in connection with a Remarketing
that is not a Failed Remarketing.

         SECTION 19. Successors and Assigns. The rights and obligations of the
Company hereunder may not be assigned or delegated to any other person without
the prior written consent of the Remarketing Agent. Subject to the provisions of
Section 10, the rights and obligations of the Remarketing Agent hereunder may
not be assigned or delegated to any other person without the prior written
consent of the Company. This Agreement shall inure to the benefit of and be
binding upon the Trust, the Company and the Remarketing Agent and their
respective successors and assigns. The terms "successors" and "assigns" shall
not include any purchaser of Preferred Securities or Subordinated Notes merely
as a result of such purchase. This Agreement shall inure to the benefit of the
Holders of the Preferred Securities (or, if applicable, holders of the
Subordinated Notes).

         SECTION 20. Headings. Section headings have been inserted in this
Agreement as a matter of convenience of reference only, and it is agreed that
such section headings are not a part of this Agreement and shall not be used in
the interpretation of any provision of this Agreement.

         SECTION 21. Severability. If any provision of this Agreement shall be
held or deemed to be or shall, in fact, be invalid, inoperative or unenforceable
as applied in any particular case in any or all jurisdictions because it
conflicts with any provisions of any constitution, statute, rule or public
policy or for any other reason, such circumstances shall not have the effect of
rendering the provision in question invalid, inoperative or unenforceable in any
other case, circumstances or jurisdiction, or of rendering any other provision
or provisions of this Agreement invalid, inoperative or unenforceable to any
extent whatsoever.

         SECTION 22. Counterparts. This Agreement may be executed in
counterparts, each of which shall be regarded as an original and all of which
shall constitute one and the same document.

         SECTION 23. Amendments. This Agreement may be amended by any instrument
in writing signed by the parties hereto; provided that any amendment to Section
5 shall require the consent of all Holders of the Preferred Securities (or,
following the distribution of Subordinated Notes to Holders of the Preferred
Securities upon dissolution of the Trust, the Subordinated Notes).


                                       18
<PAGE>   20
         SECTION 24. Notices. Unless otherwise specified, any notices, requests,
consents or other communications given or made hereunder or pursuant hereto
shall be made in writing or transmitted by any standard form of
telecommunication, including telephone, telegraph or telecopy, and confirmed in
writing. All written notices and confirmations of notices by telecommunication
shall be deemed to have been validly given or made when delivered or mailed,
registered or certified mail, return receipt requested and postage prepaid. All
such notices, requests, consents or other communications shall be addressed as
follows:

         if to the Company, to:

                           Hercules Incorporated
                           Hercules Plaza
                           1313 North Market Street
                           Wilmington, DE 19894-0001
                           Facsimile:
                           Attention: Vice President and Treasurer
                           (with a copy to General Counsel)

                  if to the Trust, to:

                           Hercules Trust V
                           c/o Hercules Incorporated
                           Hercules Plaza
                           1313 North Market Street
                           Wilmington, DE 19894-0001
                           Facsimile:
                           Attention: Vice President and Treasurer
                           (with a copy to General Counsel)

and if to the Remarketing Agent, to:

                           Banc of America Securities LLC
                           9 West 57th Street
                           New York, NY 10019
                           Facsimile: (212) 847-5124
                           Attention: William Caccamise

or to such other address as any of the above shall specify to the other in
writing.

         SECTION 25. Extension Fee. (a) Sponsor agrees to pay to BAS an
extension fee (the "EXTENSION FEE") in the amount of 2.25% of the aggregate
Liquidation Amount of the Preferred Securities in consideration for the
extension of (i) the Mandatory Redemption Date of the Securities (as set forth
in Section


                                       19
<PAGE>   21
1.01 of Amendment No. 4 to the Trust Agreement) and (ii) the Maturity Date of
the Subordinated Notes (as set forth in Section 1.01 of the Sixth Supplemental
Indenture). The Extension Fee shall be payable upon execution of this Agreement.

          (b) In the event of a Remarketing, BAS shall repay to the Company a
pro rata portion of the Extension Fee. The pro rata portion of the Extension Fee
referred to in the immediately preceding sentence shall be calculated by
multiplying (i) the total amount of the Extension Fee by (ii) the number of days
from and including the Remarketing Settlement Date to and including February 9,
2002 over the number of days from and including February 9, 2000 to and
including February 9, 2002.


                                       20
<PAGE>   22
         IN WITNESS WHEREOF, each of the Company, the Trust and the Remarketing
Agent has caused this Remarketing Agreement to be executed in its name and on
its behalf by one of its duly authorized officers as of the date first above
written.

                                       HERCULES INCORPORATED


                                       By:  ___________________________________
                                            Name:
                                            Title:


                                       HERCULES TRUST V


                                       By:  ___________________________________
                                            Name:
                                            Title:


Confirmed and Accepted
  as of the date hereof:

BANC OF AMERICA
SECURITIES LLC, not individually,
  but solely as Remarketing Agent


By: _____________________________________
    Name:
    Title: