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EXHIBIT 10(a) (xii)

THIS AMENDING AGREEMENT is made the thirteenth day of December 2011

BETWEEN

(1)HARSCO FINANCE B.V. (a company incorporated in The Netherlands) and HARSCO
INVESTMENT LIMITED (registered number 03985379) (each a "Borrower" and together
the "Borrowers");

(2)HARSCO CORPORATION (a corporation incorporated in the State of Delaware) (the
"Guarantor"); and

(3)THE ROYAL BANK OF SCOTLAND plc acting as agent for NATIONAL WESTMINSTER
BANK Plc (the "Lender")

WHEREAS

(A)The Lender, the Borrowers and the Guarantor entered into a US$50,000,000
(subsequently reduced to US$30,000,000) credit facility dated 15 December 2000,
as amended by side letters dated 19 December 2001, 6 March 2003, 19 December
2003, 17 December 2004, 12 December 2005, 8 December 2006, 31 January 2008,
8 December 2008, 22 December 2008, 10 December 2009 and 20 December 2010 (the
"Facility Agreement"); and

(B)The Lender, the Borrowers and the Guarantor have agreed to make certain
amendments to the Facility Agreement.

NOW IT IS AGREED as follows:

AMENDMENTS

        With effect from the Effective Date the following amendments shall be
made to the Facility Agreement:

1.1In the definition of "Commitment" in Clause 1.1 of the Facility Agreement
reference to $30,000,000 shall be replaced with $25,000,000.

1.2In the definition of "Final Maturity Date" in Clause 1.1 of the Facility
Agreement sub clause (a) shall be deleted in its entirety and replaced with:

(a)in relation to a Revolving Loan not converted into a Term Loan pursuant to
Clause 7.2 (Term-Out), 10 December 2012 or, if extended in accordance with
Clause 7.3 (Extension), the date provided for in Clause 7.3 (Extension); or

1.3The definition of "Margin" in Clause 1.1 of the Facility Agreement shall be
deleted in its entirety and replaced with:

"Margin" means 1.00 per cent per annum.

1.4Clause 7.2(b)(i) of the Facility Agreement shall be deleted in its entirety
and replaced with:

(i)the date to which the Final Maturity Date for each Term Loan converted from a
Revolving Loan is to be extended, which date shall be no later than 9 December
2013;

1.5Clause 7.2(b)(iv) of the Facility Agreement shall be deleted in its entirety
and replaced with:

(iv)the Final Maturity Date for any further Term Loan requested, which date
shall be no later than 9 December 2013.

1.5Clause 12.1(a) of the Facility Agreement shall be deleted in its entirety and
replaced with:

(a)The Guarantor shall pay to the Lender a commitment fee in Dollars computed at
the rate of 0.40 per cent per annum on the Available Commitment from day to day
during the Availability Period.

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1.6Clause 12.2(a) of the Facility Agreement shall be deleted in its entirety and
replaced with:

(a)The Guarantor shall pay to the Lender a utilization fee in Dollars computed
at the rate of .125 per cent per annum on the aggregate amount of the Loans
outstanding payable in respect of each day that the Base Currency Amount of all
Losses exceeds 50 per cent of the Commitment on that day.

EFFECTIVE DATE

        The Effective Date shall be the date the Lender confirms it has
received, in form and substance satisfactory to it:

2.1a copy, certified a true and up to date copy by the Secretary of Harsco
Investment Limited of a resolution of its board of directors approving the
execution and delivery of this Amending Agreement and the performance of the
obligations hereunder and authorising a person or persons (specified by name) on
behalf of it to sign and deliver this Amending Agreement and any other documents
to be delivered by it pursuant hereto and to give all notices which may be
required to be given on its behalf hereunder;

2.2a legal opinion of the General Counsel and Secretary of the Guarantor in a
form acceptable to the Lender;

2.3a legal opinion from the in house legal advisers to Harsco Finance B.V. in
the Netherlands in a form acceptable to the Lender;

2.4a copy of this Amending Agreement signed by the Borrowers and the Guarantor.

3.FEES

        The Guarantor must pay to the Lender a fee of US$37,500.

4.REPRESENTATIONS AND WARRANTIES

        The Repeating Representations and Warranties set out in Clause 19.20 of
the Facility Agreement shall be deemed repeated by the Borrowers and the
Guarantor on the date of this Amending Agreement with reference to the facts and
circumstances then existing.

5.MISCELLANEOUS

5.1All capitalised terms not otherwise defined herein shall have the meaning
ascribed to them in the Facility Agreement.

5.2All other terms and conditions of the Facility Agreement remain the same.

5.3This Amending Agreement shall be governed by and construed in accordance with
the laws of England and the parties hereto submit to the jurisdiction of the
English courts.

5.4This Amending Agreement is a Finance Document.

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SIGNED FOR AND ON BEHALF OF:

THE LENDER

By:   Ray Kinghorn Address:   250 Bishopsgate, London, EC2M 4AA, GB Attention:  
 

HARSCO FINANCE B.V.

By:   Han Jansen Address:   Harsco Corporate Office
350 Poplar Church Road
Camp Hill, PA 17011
United States Attention:    

HARSCO INVESTMENT LIMITED

By:   Han Jansen Address:   Harsco Corporate Office
350 Poplar Church Road
Camp Hill, PA 17011
United States Attention:    

HARSCO CORPORATION

By:   S.J. Schnoor Senior Vice President, CFO and Treasurer Address:   350
Poplar Church Road
Camp Hill, PA 17011
United States Attention:    

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EXHIBIT 10(a) (xii)