Document:

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                                                                    Exhibit 10.5

                            CALGON CARBON CORPORATION
                            1997 DIRECTORS' FEE PLAN

                                    SECTION 1
                         PURPOSE; RESERVATION OF SHARES
                         ------------------------------

       The purposes of the 1997 Directors' Fee Plan (the "Plan") are to provide
each Director of Calgon Carbon Corporation (the "Corporation") who is not also
an employee of the Corporation or its Subsidiaries (a "Director") with payment
alternatives for retainer (but not meeting) fees payable for future services as
a member of the Board of Directors of the Corporation (hereinafter referred to
as the "Board") or as the Chairman of any committee thereof ("Director Fees")
and to increase the identification of interests between such Directors and the
stockholders of the Corporation by providing Directors the opportunity to elect
to receive payment of Director Fees in shares of Common Stock, par value $.01
per share, of the Corporation ("Common Stock"). For purposes of the Plan, the
term "Subsidiary" means any corporation in an unbroken chain of corporations
beginning with the Corporation, if each of the corporations other than the last
corporation in the unbroken chain owns stock possessing fifty percent (50%) or
more of the total combined voting power of all classes of stock in one of the
other corporations in the chain. The aggregate number of shares of Common Stock
which may be issued under Current Stock Elections or credited to Deferred Stock
Compensation Accounts for subsequent issuance under the Plan is limited to
100,000 shares, subject to adjustment and substitution as set forth in Section
4(b).

                                    SECTION 2
                                   ELIGIBILITY
                                   -----------

       Any non-employee Director of the Corporation who is separately
compensated in the form of Director Fees for services on the Board or as the
Chairman of any committee of the Board shall be eligible to participate in the
Plan.

                                    SECTION 3
                            DIRECTOR FEES; ELECTIONS
                            ------------------------

       (a)  Payment Date. Director Fees shall be paid by the Corporation on the
twentieth day (or the next business day thereafter, if such day is not a
business day) after the annual meeting of the Corporation in each calendar year.
If a Director dies or otherwise ceases service as a Director prior to the
above-stated payment date, no such payment shall be made to the Director.

       (b)  Director Fee Payment Alternatives.  For each calendar year
beginning January 1, 1998, a Director may elect any one of the following
alternatives for the payment of Director Fees:

               (1)  to receive current payment in cash, on the date on which the
       Director Fees are payable, of all Director Fees in such calendar year;

               (2)  to receive current payment in shares of Common Stock, on the
       date on which the Director Fees are payable, of all Director Fees in such
       calendar year (a "Current Stock Election");

               (3)  to defer payment of all the Director Fees in such calendar
       year for subsequent payment in shares of Common Stock (a "Stock Deferral
       Election").
<PAGE>

       (c)  Filing and Effectiveness of Elections. The election by a Director to
receive payment of Director Fees other than in cash on the date on which the
Director Fees are otherwise payable is made by filing with the Secretary of the
Corporation a Notice of Election in the form prescribed by the Corporation (an
"Election"). In order to be effective for any calendar year, an Election must be
received by the Secretary of the Corporation on or before December 31 of the
preceding calendar year, except that if a Director files a Notice of Election on
or before five days subsequent to the Director's initial election to the office
of Director, or any subsequent re-election if immediately prior thereto such
person was not serving as a Director, the Election shall be effective on the
date of filing with respect to Director Fees payable for any portion of the
calendar year which remains at the date of such filing. An Election may not be
modified or terminated after the beginning of a calendar year for which it is
effective. Unless modified or terminated by filing a new Notice of Election on
or before December 31 immediately preceding the calendar year for which such
modification or termination is effective, an Election shall be effective for and
apply to Director Fees payable for each subsequent calendar year. Director Fees
earned at any time for which an Election is not effective shall be paid in cash
on the date when the Director Fees are otherwise payable. Any Election shall
terminate on the date a Director ceases to be a member of the Board.

       (d)  Current Stock Elections. During the period a Current Stock Election
is effective, all Director Fees payable shall be paid by the issuance to the
Director of a number of whole shares of Common Stock equal to (x) the cash
amount of the Director Fees payable divided by (y) the Fair Market Value of one
share of the Common Stock, as defined in Section 10 hereof, on the date on which
such Director Fees are payable. Any amount of Director Fees which is not paid in
Common Stock on the date otherwise payable because less than the Fair Market
Value of a whole share shall be accumulated in cash without interest and added
to the amount used in computing the number of shares of Common Stock issuable on
the next succeeding date on which Director Fees are payable under the Current
Stock Election. Any such accumulated fractional amount remaining as of the
effective date of any termination of a Current Stock Election or of the
termination of the Plan shall be paid to the Director in cash on the next
succeeding date on which Director Fees would have been payable to the Director
under the Current Stock Election. The Corporation shall issue share certificates
to the Director for the shares of Common Stock acquired. As of the date on which
the Director Fees are payable in shares of Common Stock, the Director shall be a
stockholder of the Corporation with respect to such shares.

       (b)  Stock Deferral Elections. Director Fees deferred pursuant to a Stock
Deferral Election shall be deferred and paid as provided in Sections 4 and 5. A
Stock Deferral Election shall apply to all Director Fees otherwise payable with
respect to a calendar year, or portion thereof, for which such Stock Deferral
Election is effective.

                                    SECTION 4
                       DEFERRED STOCK COMPENSATION ACCOUNT
                       -----------------------------------

       (a)  General. The amount of any Director Fees deferred in accordance with
a Stock Deferral Election shall be credited to a deferred stock compensation
account maintained by the Corporation in the name of the Director (a "Deferred
Stock Compensation Account"). A separate Deferred Stock Compensation Account
shall be maintained for each calendar year for which a Director has elected a
different number of payment installments or as otherwise determined by the
Board. On each date on which Director Fees are otherwise payable and a Stock
Deferral Election is effective for a Director, the Director's Deferred Stock
Compensation Account for that calendar year shall be credited with a number of
shares of Common Stock (including fractional shares) equal to (x) the cash
amount of the Director Fees payable divided by (y) the Fair Market Value of one
share of the Common Stock, as defined in Section 10 hereof, on the date on which
such Director Fees are payable. If a dividend or

                                     -2-
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distribution is paid on the Common Stock in cash or property other than Common
Stock, on the date of payment of the dividend or distribution to holders of the
Common Stock each Deferred Stock Compensation Account shall be credited with a
number of shares of Common Stock (including fractional shares) equal to the
number of shares of Common Stock credited to such Account on the date fixed for
determining the stockholders entitled to receive such dividend or distribution
times the amount of the dividend or distribution paid per share of Common Stock
divided by the Fair Market Value of one share of the Common Stock, as defined
in Section 10 hereof, on the date on which the dividend or distribution is
paid. If the dividend or distribution is paid in property, the amount of the
dividend or distribution shall equal the fair market value of the property on
the date on which the dividend or distribution is paid. The Deferred Stock
Compensation Account of a Director shall be charged on the date of distribution
with any distribution of shares of Common Stock made to the Director from such
Account pursuant to Section 4(c) hereof.

       (b)  Adjustment and Substitution. The number of shares of Common Stock
credited to each Deferred Stock Compensation Account, and the number of shares
of Common Stock available for issuance or crediting under the Plan in each
calendar year in accordance with Section 1 hereof, shall be proportionately
adjusted to reflect any dividend or other distribution on the outstanding Common
Stock payable in shares of Common Stock or any split or consolidation of the
outstanding shares of Common Stock. If the outstanding Common Stock shall, in
whole or in part, be changed into or exchangeable for a different class or
classes of securities of the Corporation or securities of another corporation or
cash or property other than Common Stock, whether through reorganization,
reclassification, recapitalization, merger, consolidation or otherwise, the
Board shall adopt such amendments to the Plan as it deems necessary to carry out
the purposes of the Plan, including the continuing deferral of any amount of any
Deferred Stock Compensation Account.

       (c)  Manner of Payment. The balance of a Director's Deferred Stock
Compensation Account will be paid in shares of Common Stock to the Director or,
in the event of the Director's death, to the Director's designated beneficiary,
in accordance with the Stock Deferral Election. A Director may elect at the time
of filing of the Notice of Election for a Stock Deferral Election to receive
payment of the shares of Common Stock credited to the Director's Deferred Stock
Compensation Account in annual installments rather than a lump sum, provided
that the payment period for installment payments shall not exceed ten years
following the Payment Commencement Date as described in Section 5 hereof. The
number of shares of Common Stock distributed in each installment shall be
determined by multiplying (i) the number of shares of Common Stock in the
Deferred Stock Compensation Account on the date of payment of such installment,
by (ii) a fraction, the numerator of which is one and the denominator of which
is the number of remaining unpaid installments, and by rounding such result down
to the nearest whole number of shares. The balance of the number of shares of
Common Stock in the Deferred Stock Compensation Account shall be appropriately
reduced in accordance with Section 4(a) hereof to reflect the installment
payments made hereunder. Shares of Common Stock remaining in a Deferred Stock
Compensation Account pending distribution pursuant to this Section 4(c) shall
continue to be credited with respect to dividends or distributions paid on the
Common Stock pursuant to Section 4(a) hereof and shall be subject to adjustment
pursuant to Section 4(b) hereof. If a lump sum payment or the final installment
payment hereunder would result in the issuance of a fractional share of Common
Stock, such fractional share shall not be issued and cash in lieu of such
fractional share shall be paid to the Director based on the Fair Market Value of
a share of Common Stock, as defined in Section 10 hereof, on the date
immediately preceding the date of such payment. The Corporation shall issue
share certificates to the Director, or the Director's designated beneficiary,
for the shares of Common Stock distributed hereunder. As of the date on which
the Director is entitled to receive payment of shares of Common Stock, a
Director shall be a stockholder of the Corporation with respect to such shares.

                                     -3-
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                                    SECTION 5
                            PAYMENT COMMENCEMENT DATE
                            -------------------------

       Payment of amounts in a Deferred Stock Compensation Account shall
commence on March 30 (or if March 30 is not a business day, on the first
preceding business day) of the calendar year following the calendar year during
which the Director ceases to be a member of the Board for any reason, including
death or disability.

                                    SECTION 6
                             BENEFICIARY DESIGNATION
                             -----------------------

       A Director may designate, in the Beneficiary Designation form prescribed
by the Corporation, any person to whom payments of shares of Common Stock are to
be made if the Director dies before receiving payment of all amounts due
hereunder. A beneficiary designation will be effective only after the signed
beneficiary designation form is filed with the Secretary of the Corporation
while the Director is alive and will cancel all beneficiary designations signed
and filed earlier. If the Director fails to designate a beneficiary, or if all
designated beneficiaries of the Director die before the Director or before
complete payment of all amounts due hereunder, any remaining unpaid amounts
shall be paid in one lump sum to the estate of the last to die of the Director
or the Director's designated beneficiaries, if any.

                                    SECTION 7
                          NON-ALIENABILITY OF BENEFITS
                          ----------------------------

       Neither the Director nor any beneficiary designated by the Director shall
have the right to, directly or indirectly, alienate, assign, transfer, pledge,
anticipate or encumber (except by reason of death) any amount that is or may be
payable hereunder, nor shall any such amount be subject to anticipation,
alienation, sale, transfer, assignment, pledge, encumbrance, attachment, or
garnishment by creditors of the Director or the Director's designated
beneficiary or to the debts, contracts, liabilities, engagements, or torts of
any Director or designated beneficiary, or transfer by operation of law in the
event of bankruptcy or insolvency of the Director or any beneficiary, or any
legal process.

                                    SECTION 8
                           NATURE OF DEFERRED ACCOUNTS
                           ---------------------------

       Any Deferred Stock Compensation Account and any cash fractional amount
accumulated under Section 3(d) shall be established and maintained only on the
books and records of the Corporation, and no assets or funds of the Corporation
or the Plan or shares of Common Stock of the Corporation shall be removed from
the claims of the Corporation's general or judgment creditors or otherwise made
available until such amounts are actually payable to Directors or their
designated beneficiaries as provided herein. The Plan constitutes a mere promise
by the Corporation to make payments in the future. The Directors and their
designated beneficiaries shall have the status of, and their rights to receive a
payment of cash or shares of Common Stock under the Plan shall be no greater
than the rights of, general unsecured creditors of the Corporation. No person
shall be entitled to any voting rights with respect to shares credited to a
Deferred Stock Compensation Account and not yet payable to a Director or the
Director's designated beneficiary. The Corporation shall not be obligated under
any circumstance to fund its financial obligations under the Plan, and the Plan
is intended to constitute an unfunded plan for tax purposes. However, the
Corporation may, in its discretion, set aside funds in a trust or other vehicle,
subject to the claims of its creditors, in order to assist it in

                                     -4-
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meeting its obligations under the Plan, if such arrangement will not cause the
Plan to be considered a funded deferred compensation plan under the Internal
Revenue Code of 1986, as amended.

                                    SECTION 9
                   ADMINISTRATION OF PLAN; HARDSHIP WITHDRAWAL
                   -------------------------------------------

       Full power and authority to construe, interpret, and administer the Plan
shall be vested in the Board. Decisions of the Board shall be final, conclusive,
and binding upon all parties. Notwithstanding the terms of a Stock Deferral
Election made by a Director hereunder, the Board may, in its sole discretion,
permit the withdrawal of shares credited to a Deferred Stock Compensation
Account with respect to Director Fees previously payable, upon the request of a
Director or the Director's representative, or following the death of a Director
upon the request of a Director's beneficiary or such beneficiary's
representative, if such Board determines that the Director or the Director's
beneficiary, as the case may be, is confronted with an unforeseeable emergency.
For this purpose, an unforeseeable emergency is an unanticipated emergency
caused by an event that is beyond the control of the Director or the Director's
beneficiary and that would result in severe financial hardship to the Director
or the Director's beneficiary if an early hardship withdrawal were not
permitted. The Director or the Director's beneficiary shall provide to such
Board such evidence as the Board, in its discretion, may require to demonstrate
that such emergency exists and financial hardship would occur if the withdrawal
were not permitted. The withdrawal shall be limited to the number of shares
necessary to meet the emergency. For purposes of the Plan, a hardship shall be
considered to constitute an immediate and unforeseen financial hardship if the
Director has an unexpected need for cash to pay for expenses incurred by him or
a member of his immediate family (spouse and/or natural or adopted children)
such as those arising from illness, casualty loss, or death. Cash needs arising
from foreseeable events, such as the purchase or building of a house or
education expenses, will not be considered to be the result of an unforeseeable
financial emergency. Further, a hardship shall not be deemed to exist if it may
be relieved (i) through reimbursement or compensation by insurance or otherwise,
(ii) by liquidation of the Director's assets (to the extent such liquidation
would not cause severe financial hardship to the Director) or (iii) by ceasing
deferrals under the Plan. Payment shall be made as soon as practicable after the
Board approves the payment and determines the number of shares which shall be
withdrawn, in a single lump sum from the portion of the Deferred Stock
Compensation Account with the longest number of installment payments first. No
Director shall participate in any decision of the Board regarding such
Director's request for a withdrawal under this Section 9.

                                   SECTION 10
                                FAIR MARKET VALUE
                                -----------------

       Fair market value of the Common Stock shall be the mean between the
following prices, as applicable, for the date as of which fair market value is
to be determined as quoted in The Wall Street Journal (or in such other reliable
                              --- ---- ------ -------
publication as the Board or its delegate, in its discretion, may determine to
rely upon): (a) if the Common Stock is listed on the New York Stock Exchange,
the highest and lowest sales prices per share of the Common Stock as quoted in
the NYSE-Composite Transactions listing for such date, (b) if the Common Stock
is not listed on such exchange, the highest and lowest sales prices per share of
Common Stock for such date on (or on any composite index including) the
principal United States securities exchange registered under the Securities
Exchange Act of 1934, as amended (the "1934 Act") on which the Common Stock is
listed, or (c) if the Common Stock is not listed on any such exchange, the
highest and lowest sales prices per share of the Common Stock for such date on
the National Association of Securities Dealers Automated Quotations System or
any successor system then in use ("NASDAQ"). If there are no such sale price
quotations for the date as of which fair market value is to be determined but
there are such sale price

                                     -5-
<PAGE>

quotations within a reasonable period both before and after such date, then
fair market value shall be determined by taking a weighted average of the means
between the highest and lowest sales prices per share of the Common Stock as so
quoted on the nearest date before and the nearest date after the date as of
which fair market value is to be determined. The average should be weighted
inversely by the respective numbers of trading days between the selling dates
and the date as of which fair market value is to be determined. If there are no
such sale price quotations on or within a reasonable period both before and
after the date as of which fair market value is to be determined, then fair
market value of the Common Stock shall be the mean between the bona fide bid
and asked prices per share of Common Stock as so quoted for such date on
NASDAQ, or if none, the weighted average of the means between such bona fide
bid and asked prices on the nearest trading date before and the nearest trading
date after the date as of which fair market value is to be determined, if both
such dates are within a reasonable period. The average is to be determined in
the manner described above in this Section 10. If the fair market value of the
Common Stock cannot be determined on the basis previously set forth in this
Section 10 on the date as of which fair market value is to be determined, the
Board or its delegate shall in good faith determine the fair market value of
the Common Stock on such date. Fair market value shall be determined without
regard to any restriction other than a restriction which, by its terms, will
never lapse.

                                   SECTION 11
                       SECURITIES LAWS; ISSUANCE OF SHARES
                       -----------------------------------

       The obligation of the Corporation to issue or credit shares of Common
Stock under the Plan shall be subject to (i) the effectiveness of a registration
statement under the Securities Act of 1933, as amended, with respect to such
shares, if deemed necessary or appropriate by counsel for the Corporation, (ii)
the condition that the shares shall have been listed (or authorized for listing
upon official notice of issuance) upon each stock exchange, if any, on which the
Common Stock shares may then be listed and (iii) all other applicable laws,
regulations, rules and orders which may then be in effect. If, on the date on
which any shares of Common Stock would be issued pursuant to a Current Stock
Election or credited to a Deferred Stock Compensation Account, sufficient shares
of Common Stock are not available under the Plan or the Corporation is not
obligated to issue shares pursuant to this Section 11, then no shares of Common
Stock shall be issued or credited but rather cash shall be paid in payment of
the Director Fees payable. The Board shall adopt appropriate rules and
regulations to carry out the intent of the immediately preceding sentence if the
need for such rules and regulations arises.

                                   SECTION 12
                                 GOVERNING LAW
                                 -------------

       The provisions of this Plan shall be interpreted and construed in
accordance with the laws of the Commonwealth of Pennsylvania.

                                   SECTION 13
                        EFFECT OF THE PLAN ON THE RIGHTS
                         OF CORPORATION AND STOCKHOLDERS
                         -------------------------------

       Nothing in the Plan shall confer any right to any person to continue as a
Director of the Corporation or interfere with the rights of the stockholders of
the Corporation or the Board to elect and remove Directors.

                                     -6-
<PAGE>

                                   SECTION 14
                            AMENDMENT AND TERMINATION
                            -------------------------

       The right to amend the Plan at any time and from time to time and the
right to terminate the Plan at any time are hereby specifically reserved to the
Board; provided that no amendment of the Plan shall (a) be made without
stockholder approval if stockholder approval of the amendment is at the time
required by the rules of the New York Stock Exchange or any other stock exchange
on which the Common Stock may then be listed, or (b) otherwise amend the Plan in
any manner that would cause the shares of Common Stock issued or credited under
the Plan not to qualify for the exemption from Section 16(b) of the 1934 Act
provided by Rule 16b-3. No amendment or termination of the Plan shall, without
the written consent of the holder of shares of Common Stock issued or credited
under the Plan, adversely affect the rights of such holder with respect thereto.

       Notwithstanding anything contained in the preceding paragraph or any
other provision of the Plan, the Board shall have the power to amend the Plan in
any manner deemed necessary or advisable for shares of Common Stock issued or
credited under the Plan to qualify for the exemption provided by Rule 16b-3 (or
any successor rule relating to exemption from Section 16(b) of the 1934 Act),
and any such amendment shall, to the extent deemed necessary or advisable by the
Board, be applicable to any outstanding shares of Common Stock theretofore
issued or credited under the Plan.

                                   SECTION 15
                                 EFFECTIVE DATE
                                 --------------

       The effective date and date of adoption of the Plan shall be December 8,
1997, the date of adoption of the Plan by the Board.

                                     -7-<PAGE>
                                                                    Exhibit 10.6

                       Amendment to Employment Agreement
                       ---------------------------------

     Whereas Calgon Carbon Corporation (CCC) entered into an Employment
     Agreement (Agreement) with James A. Cederna (Cederna) on March 29, 1999
     and

     Whereas the parties desire to amend the Agreement in the following
     respects and intending to be legally bound and for consideration hereafter
     acknowledge the parties agree as follows:

         1.  Paragraph 1.  Duties and Responsibilities shall be amended as
                           ---------------------------
             follows: The following words shall be deleted: "there shall be no
             Chairman of the Board of Directors."  The other portions of
             Paragraph 1 shall remain unchanged.

         2.  Paragraph 2.  Initial Term shall be replaced as follows: Employment
                           ------------
             hereunder shall commence as of January 1, 2002 and shall continue
             for a two (2) year initial term, thereafter, such employment shall
             continue unless terminated as provided for in Paragraph 4, for
             successive renewal periods of one year each, commencing January 1
             in each renewal period unless terminated pursuant to paragraph
             4(a) iii.

         3.  These amendments shall become effective January 1, 2002.

         4.  All other terms and conditions of the Agreement shall remain the
             same

                                                        12/28/01
             James A. Cederna                             Date

                                                        12/21/01
             Robert L. Yohe                               Date
<PAGE>

                             EMPLOYMENT AGREEMENT
                             --------------------

           THIS AGREEMENT, made as of March 29, 1999 between CALGON
CARBON CORPORATION (the "Company"), a Delaware corporation, and JAMES A.
CEDERNA ("Cederna"), presently residing in Panama City, Florida,

                                 WITNESSETH:

           WHEREAS, Cederna is experienced and expert in the management
of large manufacturing businesses in the United States and abroad;

           WHEREAS, the Company wishes to have the benefit of such
experience and expertise by employing Cederna, and Cederna is willing to be
employed by the Company, on the terms and conditions contained herein; and

           WHEREAS, the Company wishes to assure itself of the
continued availability of Cederna's services and of reasonable protection
against Cederna's competing against the Company, and Cederna is willing to give
such assurance in return for protection against arbitrary or unjustified
discharge, demotion and similar events;

           NOW, THEREFORE, intending to be legally bound hereby, the
Company hereby agrees to employ Cederna, and Cederna hereby agrees to be
employed by the Company, upon the following terms and conditions:

           1.     Duties and Responsibilities.  Cederna shall be the
                  ---------------------------
chief executive officer of the Company. All other officers and employees of the
Company shall report to him and be subject, directly or indirectly, to his
supervision and control. Effective upon the commencement of his employment
hereunder, (i) Cederna shall be elected President of the Company and (ii)
Cederna shall be elected a member of the Company's Board of Directors with a
term expiring at the annual meeting of the shareholders in 2000. At the annual
meeting of the shareholders in 2000 and at each annual meeting of shareholders
thereafter at which Cederna's term of office as a director expires, the Company
and its Board of Directors shall cause Cederna to be nominated for reelection
to the Company's Board of Directors, unless he is not employed by the Company
at the time of any such election. During his employment
<PAGE>

hereunder, there sail be no Chairman of the Board of Directors and Cederna
shall preside at all meetings of the Board at which he is present. Cederna
shall use his best energies and abilities in, and shall devote all his time
during business hours to, the rendering of such services and the performance of
such duties as may be appropriate for the chief executive officer of the
Company.

           2.     Initial term.   Employment hereunder shall commence
                  ------------
as of April 1, 1999, or as soon thereafter as possible in light of Cederna's
responsibilities to his current employer. Such employment shall continue for an
initial term until April 1, 2002. Thereafter such employment shall continue,
unless terminated as provided in paragraph 4, for successive renewal periods of
one year each, commencing on January 1 in each renewal period. Any failure to
renew such employment for any such period shall be deemed a termination
pursuant to paragraph 4(a)(iii).

           3.     Compensation.
                  ------------

                  (a)    Subject to paragraph 3(b), the Company shall pay
Cederna a salary at the rate of at least $41,666.67 per month until the
termination of Cederna's employment hereunder. Such salary rate shall be
reviewed at least annually by the Board of Directors of the Company and may be
increased or decreased (but not below the rate specified above) to reflect the
performance by Cederna of his duties hereunder, the results of the operations
of the Company's business or other factors. Cederna shall be entitled to
receive stock options, restricted stock and other compensation, and shall be
entitled to receive certain employee benefits, as summarized on Exhibit A
hereto. Cederna shall be reimbursed by the Company for reasonable
out-of-pocket expenses incurred by him in performing his duties hereunder.

                  (b)    If Cederna dies during his employment hereunder,
payment of compensation shall thereupon be discontinued. If for any reason
Cederna is physically or mentally disabled (as defined in paragraph 4(a)(v)
below) and the employment of Cederna is not terminated pursuant to paragraph 4,
then payment of compensation hereunder shall be continued, provided that the
proceeds of any disability insurance maintained by the Company and payable to
Cederna during the period of his disability shall be credited against the
Company's obligation to pay cash compensation to Cederna under this Agreement.
<PAGE>

           4.     Termination.
                  -----------

           (a)    Termination by the Company.
                  --------------------------

                  (i)     For Due Cause. The employment of Cederna hereunder
                          -------------
may be terminated by the Company's Board of Directors at any time, without
notice, for Due Cause (as hereinafter defined. For purposes hereof, "Due Cause"
shall mean (1) Cederna's gross negligence or willful misconduct in the
discharge of his duties and responsibilities as determined in good faith by the
Board of Directors of the Company; (ii) Cederna's material failure to obey
appropriate written instructions from the Board of Directors of the Company,
which failure has the effect of materially injuring the business or business
relationships of the Company; (iii) Cederna's conviction of a felony or of any
other crime which relates to dishonesty; (iv) Cederna's breach of his duty of
loyalty to the Company which breach has the effect of materially injuring the
Company; (v) a final determination by a court or governmental agency that
Cederna failed to comply with an applicable law, ordinance, rule or regulation
materially affecting the Company for which Cederna, in his capacity as the
chief executive officer, was directly responsible; or (vi) the material breach
of any term or provision of this Agreement by Cederna.

                  (ii)    Expiration of initial term. The employment of Cederna
                          --------------------------
hereunder may be terminated by the Company's Board of Directors as of the end
of the initial term specified in paragraph 2, for any reason or no reason, upon
at least 90 days' notice to Cederna prior to the effective date of such
termination. In the event of a termination by the Company pursuant to this
paragraph 4(a)(ii), the termination shall be deemed to be without Due Cause and
shall be governed by paragraph 5(a)(i) or, if there has been a Change of
Control prior to such termination, shall be governed by paragraph 5(a)(ii).

                  (iii)   Board dissatisfaction. The employment of Cederna
                          ---------------------
hereunder may be terminated by the Company's Board of Directors at any time
after the end of the initial term specified in paragraph 2 and prior to any
Change of Control (as defined in paragraph 4(c)), upon at least 90 days' notice
to Cederna prior to the effective date of such termination,
<PAGE>

for Cederna's failure or inability to perform his duties hereunder in a manner
satisfactory to the Board. In the event of a termination by the Company
pursuant to this paragraph 4(a)(iii), the termination shall be deemed to be
without Due Cause and shall be governed by paragraph 5(a)(i).

                  (iv)    Change of Control. If a Change of Control occurs, the
                          -----------------
employment of Cederna hereunder may be terminated by the Company's Board of
Directors at any time after such Change of Control, for any reason or no
reason, upon at least 90 days' notice to Cederna prior to the effective date of
such termination.

                  (v)     Death or disability. The employment of Cederna
                          -------------------
hereunder shall terminate automatically upon Cederna's death. If for any reason
Cederna becomes physically or mentally disabled so as to be unable to perform
all his duties hereunder, in the judgment of the Board of Directors made in
good faith, then the employment of Cederna hereunder may be terminated by the
Board, without notice; provided that such termination shall not be effective
until the first day on which Cederna is entitled to accrue payments under the
Company's long-term disability plan.

           (b)    Termination by Cederna.
                  ----------------------

                  (i)     Breach by Companv. The employment of Cederna hereunder
                          -----------------
may be terminated by Cederna, upon at least 30 days' notice to the Company
prior to the effective date of such termination, for any material breach of
this Agreement by the Company; provided, however, that if the Company causes,
permits or institutes either (1) a material diminution of Cederna's
responsibilities with the Company or (ii) a requirement by the Company that
Cederna report to any other person or group other than the Company's Board of
Directors, then a material breach of this Agreement by the Company shall be
deemed to exist and such resignation shall be deemed, for purposes of this
Agreement, to be a termination by the Company without Due Cause and shall be
governed by paragraph 5(a)(i).

                  (ii)    Expiration of initial term. The employment of Cederna
                          --------------------------
hereunder may be terminated by Cederna as of the end of the initial term
specified in Paragraph 2, for any
<PAGE>

reason or no reason, upon at least 90 days' notice to the Company prior to the
effective date of such termination.

                  (iii)   Resignation after initial term. The employment of
                          ------------------------------
Cederna hereunder may be terminated by Cederna at any time after the end of the
initial term specified in Paragraph 2, upon at least 90 days' notice to the
Company prior to the effective date of such termination, for any reason or no
reason.

                  (iv)    Resignation after Change of Control. The employment
                          -----------------------------------
of Cederna hereunder may be terminated by Cederna at any time after a Change of
Control, upon at least 90 days' notice to the Company prior to the effective
date of such termination, for any reason or no reason; provided, however, that
if such resignation follows either (1) a material diminution of Cederna's
responsibilities with the Company or (ii) a requirement by the Company that
Cederna report to any other person or group other than the Company's Board of
Directors, then a material breach of this Agreement by the Company shall be
deemed to exist and such resignation shall be deemed, for purposes of this
Agreement, to be a termination by the Company without Due Cause and shall be
governed by paragraph 5(a)(ii).

                  (v)     Resignation after disability. If for any reason
                          ----------------------------
Cederna becomes physically or mentally disabled so as to be unable to perform
all his duties hereunder, in Cederna's judgment made in good faith, then the
employment of Cederna hereunder may be terminated by Cederna, without notice,
but without prejudice to Cederna's rights under any disability insurance
maintained by the Company and applicable to him.

           (c)    Definition of Change of Control. For all purposes of this
                  -------------------------------
Agreement, a Change of Control shall be deemed to have occurred when (i) the
company is merged or consolidated with another corporation which is not then
controlled by the Company, or (ii) a majority of the Company's assets are sold
or otherwise transferred to another such corporation or to a partnership, firm
or one or more individuals not so controlled, or (iii) a majority of the
members of the Company's Board of Directors consists of persons who were not
nominated for election as directors by or on behalf of the Board of Directors
itself or with the express
<PAGE>

concurrence of the Board of Directors, or (iv) a single person, or a group of
persons acting in concert, obtains the power to cause the nominees of such
person or group to be elected as a majority of the directors of the Company.

           (d)    Resignation as director. Upon the termination of Cederna's
                  -----------------------
employment by the Company at any time and for any reason or no reason, Cederna
shall be deemed to have resigned from the Company's Board of Directors. Upon
the request of the Company, Cederna shall deliver to the Company a written
confirmation of such resignation.

           5.     Severance pay; benefits.
                  -----------------------

           (a)    Termination by the Company.
                  --------------------------

                  (i)     Board dissatisfaction. If Cederna's employment
                          ---------------------
           hereunder is terminated by the Board of Directors pursuant to
           paragraph 4(a)(iii) or without Due Cause, then the Company shall pay
           Severance Compensation to Cederna throughout the Severance Period.
           The term "Severance Compensation" is defined in paragraph 5(c). For
           the purposes of this paragraph 5(a)(i), the term "Severance Period"
           shall mean the period of 24 calendar months after the month in which
           such termination becomes effective. In the event of such a
           termination, Cederna shall not be entitled to receive or retain any
           stock options or restricted stock not vested on the date notice of
           such termination is given to Cederna.

                  (ii)    Change of Control. If Cederna's employment hereunder
                          -----------------
           is terminated by the Board of Directors pursuant to paragraph
           4(a)(iv), then the Company shall pay Severance Compensation to
           Cederna throughout the Severance Period. For the purposes of this
           paragraph 5(a)(ii), the term "Severance Period" shall mean the
           period of 36 calendar months after the month in which such
           termination becomes effective. In the event of such a termination,
           all stock options and restricted stock not vested on the date notice
           of such termination is given to Cederna shall immediately vest as of
           the date of such notice. For the purposes of this paragraph
           5(a)(ii), any termination of Cederna's employment by the Board of
           Directors (other than a termination for Due Cause) shall be deemed
           to be pursuant to paragraph 4(a)(iv) if notice of such termination
           is given within 120 days prior to
<PAGE>

           the date when a Change of Control is deemed to have occurred
           pursuant to paragraph 4(c).

                  (iii)  Other terminations. If Cederna's employment hereunder
                         ------------------
           is terminated by the Board of Directors for any reason or in any
           manner except pursuant to paragraphs 4(a)(iii) or 4(a)(iv), then
           Cederna shall not be entitled to any severance pay and Cederna shall
           not be entitled to receive or retain any stock options or restricted
           stock not vested on the date notice of such termination is given to
           Cederna.

           (b)    Termination by Cederna.
                  ----------------------

                  (i)     Breach by Company. If Cederna's employment hereunder
                          -----------------
           is terminated by Cederna pursuant to paragraph 4(b)(i), then the
           Company shall pay Severance Compensation to Cederna throughout the
           Severance Period. For the purposes of this paragraph 5(a)(i), the
           term "Severance Period" shall mean the period of three calendar
           months after the month in which such termination becomes effective,
           or the period ending on the date when the initial term specified in
           paragraph 2 expires, whichever is longer. In the event of such a
           termination, all stock options and restricted stock not vested on
           the date notice of such termination is given to Cederna shall
           immediately vest as of the effective date of such termination.

                  (ii)    Change of Control. If Cederna's employment hereunder
                          -----------------
           is terminated by Cederna pursuant to paragraph 4(b)(iii), then the
           Company shall pay Severance Compensation to Cederna throughout the
           Severance Period. For the purposes of this paragraph 5(h)(ii), the
           term "Severance Period" shall mean the period of six calendar months
           after the month in which such termination becomes effective. In the
           event of such a termination, all stock options and restricted stock
           not vested on the date notice of such termination is given to
           Cederna shall immediately vest as of the effective date of such
           termination.

                  (iii)   Other terminations. If Cederna's employment hereunder
                          ------------------
           is terminated by Cederna for any reason or in any manner except
           pursuant to paragraphs 4(b)(i) or 4(b)(iv), then Cederna shall not
           be entitled to any severance pay and
<PAGE>

           Cederna shall not be entitled to receive or retain any stock options
           or restricted stock not vested on the date notice of such
           termination is given to Cederna.

                  (c)    Severance Compensation; Severance Period. "Severance
                         ----------------------------------------
Compensation," for purposes of this Agreement, shall mean, for each month of
the appropriate Severance Period, one twelfth of the amount of salary and cash
bonus received by Cederna from the Company for the calendar year immediately
prior to the year in which notice of such termination is given. For the purpose
of calculating Severance Compensation, Cederna shall be deemed to have received
at least $750,000 of salary and cash bonus for 1999. In any event the Severance
Period shall end on the date, if ever, when Cederna is employed by another
employer for total cash compensation equal to at least 90% of Severance
Compensation.

                  (d)    Accrued salary: certain employee benefits. In the event
                         -----------------------------------------
of any such termination by the Company or Cederna, the Company shall pay to
Cederna all salary accrued to the effective date of such termination and not
theretofore paid to Cederna. In the event of any such termination by the
Company or Cederna pursuant to paragraphs 5(a)(i), 5(a)(ii), 5(b)(i) or
5(b)(ii), the Company shall provide for Cederna during the Severance Period the
same or equivalent medical, dental, disability and insurance benefits as were
provided for Cederna at the time of such termination. Other rights and benefits
of Cederna under the benefit plans and programs of the Company, or which are
paid for by the Company, shall be determined in accordance with such plans and
programs.

           6.     Confidential information, etc.
                  -----------------------------

           (a)    Cederna recognizes and acknowledges that: (i) in the course
of Cederna's employment by the Company it will be necessary for Cederna to
acquire information which could include, in whole or in part, information
concerning the sales of the Company (for purposes of this paragraph 6 and of
paragraph 7, the term "Company" is defined in paragraph 8(d)), the Company's
sales volume, sales methods, sales proposals, customers and prospective
customers, identity of customers and prospective customers, identity of key
purchasing personnel in the employ of customers and prospective customers,
amount or kind of customers' purchases from the Company, the Company's sources
of supply, computer
<PAGE>

programs, system of documentation, special hardware, product hardware, related
software development, manuals, formulae, processes, methods, machines,
compositions, ideas, improvements, inventions or other confidential or
proprietary information belonging to the Company or relating to the Company's
affairs (collectively referred to herein as the "Confidential Information");
(ii) the Confidential Information is the property of the Company; (iii) the
use, misappropriation or disclosure of the Confidential Information would
constitute a breach of trust and could cause irreparable injury to the Company;
and (iv) it is essential to the protection of the Company's good will and to
the maintenance of the Company's competitive position that the Confidential
Information be kept secret and that Cederna not disclose the Confidential
Information to others or use the Confidential Information to Cederna's own
advantage or the advantage of others. Notwithstanding anything set forth above,
the term "Confidential Information" does not include information which (i) is
at the time of disclosure to Cederna or later becomes generally known to the
public other than as a result of disclosure directly or indirectly by Cederna,
(ii) was available to Cederna on a non-confidential basis prior to the
disclosure of such Confidential Information to Cederna pursuant to this
Agreement, provided that the source of such information is not and was not
bound by a confidentiality agreement with, or other obligation of secrecy to,
the Company or the Company's representatives, or (iii) becomes available to
Cederna on a non-confidential basis from a source other than the Company or the
Company's representatives, provided that such source is not and was not bound
by a confidentiality agreement with, or other obligation of secrecy to, the
Company or its representatives.

           (b)    Cederna further recognizes and acknowledges that it is
essential for the proper protection of the business of the Company that Cederna
be restrained (i) from soliciting or inducing any employee of the Company to
leave the employ of the Company, (ii) from hiring or attempting to hire any
employee of the Company, (iii) from soliciting the trade of or trading with the
customers and suppliers of the Company for any business purpose, and (iv) from
competing against the Company for a reasonable period.

           7.     Non-compete.
                  -----------
<PAGE>

           (a)    Cederna agrees to hold and safeguard the Confidential
Information in trust for the Company, its successors and assigns and agrees
that he shall not, without the prior written consent of the Company, disclose
or make available to anyone for use outside the Company at any time, either
during his employment by the Company or subsequent to the termination of his
employment by the Company for any reason, any of the Confidential Information,
whether or not developed by Cederna, except as required in the performance of
Cederna's duties to the Company.

           (b)    Upon the termination of Cederna's employment by the
Company or by Cederna for any reason, Cederna shall promptly deliver to the
Company all originals and copies of correspondence, drawings, blueprints,
financial and business records, marketing and publicity materials, manuals,
letters, notes, notebooks, reports, flow-charts, drawings, programs, proposals
and any documents in Cederna's possession, if any, concerning the Company's
customers or concerning products or processes used by the Company and, without
limiting the foregoing, shall promptly deliver to the Company any and all other
documents or materials containing or constituting Confidential Information.

           (c)    Cederna agrees that during his employment by the Company
he shall not, directly or indirectly, solicit the trade of, or trade with, any
customer, prospective customer or supplier of the Company for any business
purpose other than for the benefit of the Company. Cederna further agrees that
during the Severance Period or for a period of two years after termination of
employment hereunder, whichever is longer, Cederna shall not, directly or
indirectly, solicit the trade of, or trade with, any customers or suppliers, or
prospective customers or suppliers, of the Company in a Competing Business, or
solicit or induce, or attempt to solicit or induce, any employee of the Company
to leave the Company for any reason whatsoever or hire any employee of the
Company.

           (d)    Cederna covenants and agrees that during the period of
Cederna's employment hereunder and during the Severance Period or for a period
of two years after termination of employment hereunder, whichever is longer,
Cederna shall not, in any Competitive Territory, engage, directly or
indirectly, whether as principal or as agent, officer, director, employee,
consultant, shareholder or otherwise, alone or in association with any other
person, corporation or other entity, in any Competing Business.
<PAGE>

For purposes of this Agreement, (i) the term "Competing Business" shall mean
any person, corporation or other entity which sells or attempts to sell any
products or services which are the same as or similar to the products and
services sold by the company at any time and from time to time during the last
two years prior to the termination of Cederna's employment hereunder, and (ii)
the term "Competitive Territory" shall mean the United States of America, Great
Britain, Belgium, Germany, Japan and any other nation in which, to the
knowledge of Cederna, the Company has made or considered making such sales,
either itself or through a subsidiary, affiliate, distributor or joint venture
partner, during the last two years prior to the termination of Cederna's
employment hereunder

                   8.     Injunctive and other relief.
                          ---------------------------

                   (a)    Cederna represents that his experience and
capabilities are such that the provisions of paragraphs 6 and 7 will not
prevent him from earning his livelihood, and acknowledges that it would cause
the Company serious and irreparable injury and cost if Cederna were to use his
ability and knowledge in competition with the Company or to otherwise breach
the obligations contained in said paragraphs.

                   (b)    In the event of a breach by Cederna of the terms of
this Agreement, the Company shall be entitled, if it shall so elect, to
institute legal proceedings to obtain damages for any such breach, or to
enforce the specific performance of this Agreement by Cederna and to enjoin
Cederna from any further violation of this Agreement and to exercise such
remedies cumulatively or in conjunction with all other rights and remedies
provided by law. Cederna acknowledges, however, that the remedies at law for
any breach by him of the provisions of this Agreement may be inadequate and
that the Company shall be entitled to injunctive relief against him in the
event of any breach whether or not the Company may also be entitled to recover
damages hereunder.

                   (c)    It is the intention of the parties that the
provisions of paragraphs 6 and 7 hereof shall be enforceable to the fullest
extent permissible under applicable law, but that the unenforceability (or
modification to conform to such law) of any provision or provisions hereof
shall not render unenforceable, or impair, the remainder thereof. If any
provision or provisions
<PAGE>

hereof shall be deemed invalid or unenforceable, either in whole or in part,
this Agreement shall be deemed amended to delete or modify, as necessary, the
offending provision or provisions and to alter the bounds thereof in order to
render it valid and enforceable.

                   (d)    For the purposes of paragraphs 6 and 7 and this
paragraph 8, the term "Company" shall include Calgon Carbon Corporation and any
of its domestic or foreign subsidiaries.

                   9.     Arbitration. Any dispute arising out of or relating
                          -----------
to this Agreement or the breach, termination or validity hereof shall be
finally settled by arbitration conducted expeditiously in accordance with the
Center for Public Resources Rules for Non-Administered Arbitration of Business
Disputes by three independent and impartial arbitrators. Each party shall
appoint one of such arbitrators, and the two arbitrators so appointed shall
appoint the third arbitrator. The arbitration shall be governed by the United
States Arbitration Act, 9 U.S.C. [sec][sec]1-16, and judgment on the award
rendered by the arbitrators may be entered by any court having jurisdiction
thereof. The place of arbitration shall be Pittsburgh, Pennsylvania. The
arbitrators are not empowered to award damages in excess of compensatory
damages and each party hereby irrevocably waives any damages in excess of
compensatory damages.

                   10.    Governing law. This Agreement shall be governed by
                          -------------
and construed in accordance with the laws of the Commonwealth of Pennsylvania
without giving effect to any choice or conflict of law provision or rule
(whether of the Commonwealth of Pennsylvania or any other jurisdiction) that
would cause the application of the laws of any jurisdiction other than the
Commonwealth of Pennsylvania.

                   11.    Amendments, waivers, etc. No amendment of any
                          ------------------------
provision of this Agreement, and no postponement or waiver of any such
provision or of any default, misrepresentation, or breach of warranty or
covenant hereunder, whether intentional or not, shall be valid unless such
amendment, postponement or waiver is in writing and signed by or on behalf of
the Company and Cederna. No such amendment, postponement or waiver shall be
deemed to extend to any prior or subsequent matter, whether or not similar to
the subject-matter of such amendment, postponement or waiver. No failure or
delay on the part of the Company or Cederna in exer-
<PAGE>

casing any right, power or privilege under this Agreement shall operate as a
waiver thereof nor shall any single or partial exercise of any right, power or
privilege hereunder preclude any other or further exercise thereof or the
exercise of any other right, power or privilege.

                   12.    Assignment. The rights and duties of the Company
                          ----------
under this Agreement may be transferred to, and shall be binding upon, any
person or company which acquires the Company or its business by merger,
purchase or otherwise. Except as otherwise provided in this paragraph 12,
neither the Company nor Cederna may transfer any of their respective rights and
duties hereunder except with the written consent of the other party hereto.

                   13.    Interpretation, etc. The Company and Cederna have
                          -------------------
participated jointly in the negotiation and drafting of this Agreement. If an
ambiguity or question of intent or interpretation arises, this Agreement shall
be construed as if drafted jointly by the Company and Cederna and no
presumption or burden of proof shall arise favoring or disfavoring the Company
or Cederna because of the authorship of any of the provisions of this
Agreement. The word "including" shall mean including without limitation. The
rights and remedies expressly specified in this Agreement are cumulative and
are not exclusive of any rights or remedies which either party would otherwise
have. The paragraph headings hereof are for convenience only and shall not
affect the meaning or interpretation of this Agreement.

                   14.    Integration; counterparts. This Agreement constitutes
                          -------------------------
the entire agreement among the parties and supersedes any prior understandings,
agreements or representations by or among the parties, written or oral, to the
extent they relate to the subject matter hereof. This Agreement may be executed
in one or more counterparts, each of which shall be deemed an original but all
of which together shall constitute one and the same instrument. It shall not be
necessary in making proof of this Agreement to produce or account for more than
one such counterpart.

                   WITNESS the due execution hereof as of the date first above
written.

Attest:                                               CALGON CARBON CORPORATION
<PAGE>

                                       BY
                                               Robert L. Yohe
[Corporate Seal]

Witness:

                                       ( L . S . )
                                               JAMES A. CEDERNA
<PAGE>

Exhibit A

                   1.     Stock. As soon as practicable after his employment
                          -----
hereunder commences, but in no event more than thirty (30) days following
execution of this Agreement by the parties, the Company shall issue to Cederna
75,000 shares of its common stock, in consideration of his entering into this
Agreement. Such shares will not be registered under the Securities Act of 1933,
and the certificates for such shares shall bear a legend indicating that they
may not be sold or otherwise transferred by Cederna except in compliance with
that Act and any applicable state securities laws. The Company shall pay to
Cederna as additional compensation cash in an amount equal to the amount of any
federal and state income taxes required to be paid by Cederna as a result of
his receipt of the stock described in this paragraph, payable immediately upon
determination by Cederna's tax advisors of the amount of such tax liability or
estimated liability.

                   2.     Initial stock options. On April 21, 1999 the Company
                          ---------------------
shall grant to Cederna options to purchase 400,000 shares of its common stock.
Such options shall be granted under the Company's Stock Option Plan, if and to
the extent that such options are then available for grant under the Plan. If
and to the extent that such options are not then available for grant under the
Plan, such options shall be granted outside the Plan.

                   The option price shall be the average of the high and low
sales prices for the common stock on the New York Stock Exchange on the date of
grant, as presently provided in the Stock Option Plan. 25% of such options
shall vest on the date of grant and be exercisable immediately. An additional
25% of such options shall vest and become exercisable on March 31 of each of
the years 2000, 2001 and 2002, respectively, if Cederna is employed by the
Company on those dates. All such options shall expire on April 20, 2009. The
Company and Cederna shall enter into the Company's standard agreement with
respect to such stock options.

                   3.     Annual stock options. On the first business day in
                          --------------------
April in each year after 1999, the Company shall grant to Cederna options to
purchase 100,000 shares of its common stock, unless Cederna is not employed by
the Company on such business day or unless notice of the termination of his
employment by the Company has been given prior to such business day. Such
options shall be granted under the Company's Stock Option Plan, as then in
effect,
<PAGE>

       if and to the extent that such options are then available for grant
under the Plan. If and to the extent that such options are not then available
for grant under the Plan, such options shall be granted outside the Plan.

                   The option price shall be the average of the high and low
sales prices for the common stock on the New York Stock Exchange on the date of
grant, as presently provided in the Stock Option Plan. Such options shall vest
and become exercisable in installments upon a schedule then typically used by
the Company for options granted to its senior executive officers, unless
Cederna is not employed by the Company on the vesting date or unless notice of
the termination of his employment by the Company has been given prior to the
vesting date. All such options shall expire on the tenth anniversary of their
date of grant. The Company and Cederna shall enter into the Company's standard
agreement with respect to such stock options.

                   4.    Annual bonus. Cederna shall be eligible to participate
                         ------------
in the Officers Incentive Plan of the Company, which provides for annual cash
bonuses to officers under certain circumstances. Such plan shall be amended,
however, to provide in the case of the chief executive officer that no such
bonus shall exceed 125%, rather than 100%, of his annual salary, and that he
shall be entitled to a bonus of at least $250,000 for 1999.

                   5     Pension. Cederna shall be entitled to participate in
                         -------
the Company's Retirement Plan for Salaried Employees, as it may be amended from
time to time. The Company shall make appropriate provisions so that the
Retirement Income to be received by Cederna upon his retirement from employment
by the Company, when combined with the amounts then payable to Cederna under
the retirement plans of former employers of Cederna, will not be less than the
Retirement Income he would have received under the Retirement Plan for Salaried
Employees (without the application of any maximum amount of Retirement Income
specified in the Plan) if his years of Credited Service under the Plan had
included the years of his full-time employment by such other employers. A
hypothetical example of the calculation of such Retirement Income is attached
hereto as Exhibit A-1.

                   6.    Other benefit plans. Cederna shall be entitled to
                         -------------------
participate in other employee benefit plans maintained by the Company from time
to time for the benefit of its employees, on no
<PAGE>

less favorable a basis than the basis applicable to other officers of the
Company elected by the Board of Directors, except for benefits, if any, not
legally available to Cederna because of his status, compensation or similar
factors. Such employee benefits presently include life insurance, medical and
dental insurance, disability insurance and others.

                   7.    Automobile; club memberships. The Company shall
                         ----------------------------
provide an automobile for Cederna's business and personal use. Such automobile
shall be a Lexus sport utility vehicle or equivalent, at Cederna's choice, and
shall be replaced by the Company at two-year intervals. Cederna shall pay the
cost of fuel, maintenance and storage of such automobile. The Company shall use
its best efforts to cause Cederna and his spouse to be admitted to membership
in the Duquesne Club and in such country club as they may choose, and the
Company shall pay the initiation fees and periodic dues for such memberships.

                   8.    Tax Planning. The Company shall provide for Cederna's
                         ------------
benefit annual tax and financial planning assistance, at the Company's sole
expense.

                   9.    Vacation. Cederna shall be entitled to three weeks of
                         --------
vacation in each calendar year, prorated to reflect the actual number of days
in such year that Cederna is employed hereunder. The Company shall not make any
cash payment to Cederna in lieu of vacation days not taken by him.

                   10.   Relocation.
                         ----------

                   (a)   Until Cederna has established a permanent residence
for himself and his spouse near Pittsburgh, which is expected to occur in the
summer of 1999, the Company shall pay, or reimburse Cederna for, his reasonable
living expenses in or near Pittsburgh.

                   (b)   The Company shall pay, or reimburse Cederna for, the
cost of transferring the personal property and household goods of Cederna and
his spouse from Panama City, Florida, to their new residence near Pittsburgh.
This will include the cost of insurance, packing, unpacking, temporary storage
and shipping.

                   (c)   The Company shall pay or reimburse Cederna and his
spouse for a reasonable number of trips from Panama City, Florida
<PAGE>

and return for the purpose of searching for a permanent residence near
Pittsburgh.

                   (d)   The Company shall pay or reimburse Cederna for real
estate brokers' commissions and closing costs (such as title search, escrow
fees, tax stamps, recording fees, and lenders' "points") incurred by Cederna in
connection with the purchase or rental, and related financing, of a permanent
residence for him and his spouse near Pittsburgh and the sale of his existing
residence in Panama City, Florida.

                   (e)   Cederna and his spouse shall use their best efforts to
sell their present residence in Panama City, Florida as soon as possible. If
such a sale does not take place by July 1, 1999, the Company shall either (1)
purchase such residence from Cederna and his spouse for a purchase price,
payable in cash at the closing, equal to the fair market value of such
residence determined as set forth below, or (ii) reimburse Cederna for the
after-tax cost to Cederna and his spouse, determined as set forth below, of
owning such residence from July 1, 1999 until it is sold. The Company shall be
entitled to choose at any time between alternatives (1) and (ii). The fair
market value of such residence shall be determined by a professional appraiser
active in the Panama City area and mutually satisfactory to Cederna and the
Company or, if Cederna and the Company do not agree on such an appraiser, then
by three professional appraisers active in the Panama City area, one of which
shall be selected by Cederna, one by the Company, and the third by the other
two appraisers. The after-tax cost to Cederna and his spouse of owning such
residence shall include mortgage payments (both principal and interest), real
estate taxes, and utilities and maintenance appropriate for an unoccupied
residence.

                   This Exhibit A is merely a summary of general terms. The
actual terms and conditions of the stock, stock options, retirement benefits
and other matters covered by existing plans of the Company shall be governed by
such Plans and the documents to be issued to Cederna thereunder.
<PAGE>

EXHIBIT A-1

Assumptions:
-----------

           Retire at age 55

           Credit for all years of service at all previous
           employers (33 years at age 55)

           Final average compensation=$750,000, inflated at 5% for
           7 years=$1,055,000

Calculation:
-----------

           1.05% x 33 x$1,055,000 =      $365,555
           0.50% x 33 x $ 955,000/1/ =    157,575
                                          -------
                                          523,133
           Reduction factor = 21%             .79
                                         $413,275

Reduce Calgon Carbon pension obligation by amounts paid by other former
employers of Cederna (Dow Chemical pension is $43,200 per year)

                   Net Calgon Carbon pension obligation = $370,075

/1/ Estimated Social Security reduction.

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00036-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00036-of-00352.parquet"}]]