LEASE AGREEMENT

EXHIBIT 10.20

Tenant: International Mill Service Inc.

Suite No.:

LEASE

THIS LEASE (“Lease”) is entered into as of the 3 ^rd day May, 2005, between BRANDYWINE OPERATING PARTNERSHIP, L.P., a Delaware limited partnership (“Landlord”), and INTERNATIONAL MILL SERVICE, INC., a Pennsylvania corporation with its principal place of business at 1155 Business Center Drive, Horsham, Pennsylvania (“Tenant”).

Landlord’s predecessor and Tenant’s predecessor are parties to a certain Lease Agreement dated December 21, 1990, as amended by Lease Modification Agreement dated March 28, 1996, Second Lease Modification Agreement dated April 7,1996 and Third Amendment to Lease dated September 26, 1997 (“Existing Lease”). Landlord and Tenant desire to amend the Existing Lease for the period from the date hereof through March 31, 2006 in accordance with Article 28 hereof and thereafter terminate the Existing Lease as of March 31, 2006 and put into effect on April 1, 2006, the provisions of Articles 1 through 27 hereof. In consideration of the mutual covenants stated below, and intending to be legally bound, the parties covenant and agree as follows:

1. PREMISES . Effective April 1, 2006, Landlord leases to Tenant and Tenant leases from Landlord Suite No. 200, which the parties stipulate and agree is 24,038 shown on the plan which shall be prepared in accordance with Article28 hereof and thereafter attached hereto as Exhibit “A” (“Premises”), located at 1155 Business Center Drive, Horsham, Pennsylvania (“Building”), which is a part of the project located at Horsham Business Center, Horsham, Pennsylvania (“Project”). Except as set forth in Article 28 the Premises are delivered “As Is”.

2. TERM . The Term of this Lease shall commence on April 1, 2006 (the “Commencement Date”). The Term shall be for a period of sixty (60) months (‘Term”) ending on the last day of the calendar month. The Commencement Date shall be confirmed by Landlord and Tenant by the execution of a Confirmation of Lease Term (“COLT”) in the form attached hereto as Exhibit “B ”. If Tenant fails to execute or object to the COLT within ten (10) business days of its delivery, Landlord’s determination of such dates shall be deemed accepted by Tenant.

3. FIXED RENT; SECURITY DEPOSIT .

(a) Commencing on the Commencement Date and on the first (l ^st ) day of each month thereafter during the Term, Tenant shall pay to Landlord without notice or demand, and without set-off, deduction or counterclaim (except as otherwise set forth in this Lease) the monthly installment of annual Fixed Rent as set forth below by (i) check sent to Landlord, P.O. Box 8538-363, Philadelphia, PA 19171 or (ii) wire transfer of immediately available funds to the account at Wachovia Bank, Salem NJ account no. 2030000359075 ABA #031201467; such transfer to be confirmed by Landlord’s accounting department upon written request by Tenant All payments must include the following information: Building #115 and Lease #              . The Lease # will be provided to Tenant in the Confirmation of Lease Term Fixed Rent and all other sums due from Tenant under this Lease shall collectively be defined as “Rent”.

(b) Tenant shall pay the first full month’s installment of Fixed Rent (or such initial partial month) and the Security Deposit (as defined below) by two separate checks upon the Tenant’s execution of this Lease. If any amount due from Tenant is not paid to Landlord when due. Tenant shall also pay as Additional Rent (as defined in Article 4 hereof) a late fee of ten (10%) percent of the total payment then due. The late fee shall accrue on the initial date of a payment’s due date, irrespective of any grace period granted hereunder. Tenant shall be required to continue to post a security deposit of $28,795 under this Lease (the “Security Deposit”), as security for the prompt and complete performance by Tenant of every provision of this Lease. No interest shall be paid to Tenant on the Security Deposit. If Tenant fails to perform any of its obligations hereunder. Landlord may use, apply or retain the whole or any part of the Security Deposit for the payment of (i) any rent or other sums of money which Tenant may not have paid when due, (ii) any sum expended by Landlord in accordance with the provisions of this Lease, and/or (iii) any sum which Landlord may expend or be required to expend by reason of Tenant’s default. The use of the Security Deposit by Landlord shall not prevent Landlord from exercising any other remedy provided by this Lease or

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by law and shall not operate as either liquidated damages or as a limitation on any recovery to which Landlord may otherwise be entitled. If any portion of the Security Deposit is used, applied or retained by Landlord, Tenant agrees, within five (5) days after the written demand therefor is made by Landlord, to deposit cash with the Landlord in an amount sufficient to restore the Security Deposit to its original amount. In addition to the foregoing, if Tenant defaults (irrespective of the fact that Tenant cured such default) more than once in its performance of a monetary obligation and such monetary defaults aggregate in excess of $50,000 under this Lease, Landlord may require Tenant to increase the Security Deposit to the greater of twice the (i) Fixed Rent then paid monthly, or (ii) the initial amount of the Security Deposit. If Tenant shall fully comply with all of the provisions of this Lease, the Security Deposit, or any balance thereof, shall be returned to Tenant within a reasonable time after the later of expiration of the Term or Tenant’s surrender of the Premises as required hereunder. Upon the return of the Security Deposit to the original Tenant hereunder, or the remaining balance thereof, Landlord shall be completely relieved of liability with respect to the Security Deposit. In the event of a transfer of the Building, Landlord shall have the right to transfer the Security Deposit and Landlord shall thereupon be released by Tenant from all liability for the return of such Security Deposit. Upon the assumption of such Security Deposit by the transferee, Tenant agrees to look solely to the new landlord for the return of said Security Deposit.

4. ADDITIONAL RENT . Effective April 1, 2006 but commencing January 1, 2007, and in each calendar year thereafter during the Term, Tenant shall pay in advance on a monthly basis to Landlord, Tenant’s Share of the “Recognized Expenses”, without deduction, counterclaim or setoff, to the extent such Recognized Expenses exceed the Recognized Expenses in calendar year 2006 (“Base Year”). Tenant’s Share shall be 46.77% which is the percentage calculated by dividing the total square footage of the Premises into the total square footage of the Building which is 51,388. Recognized Expenses are (i) all reasonable operating costs and expenses related to the maintenance, operation and repair of the Project incurred by Landlord, including but not limited to management fee not to exceed five (5%) percent of Rent; common area electric; and capital expenditures and capital repairs and replacements shall be included as operating expenses solely to the extent of the amortized costs of same over the useful life of the improvement in accordance with generally accepted accounting principles such useful life not to exceed ten (10) years; (ii) all insurance premiums payable by Landlord for insurance with respect to the Project and (iii) Taxes payable on the Project. Each of the Recognized Expenses shall for all purposes be treated and considered as Additional Rent. Tenant shall pay, in monthly installments in advance, on account of Tenant’s Share of Recognized Expenses, the estimated amount of the increase of such Recognized Expenses for such year in excess of the Base Year as determined by Landlord in its reasonable discretion. Prior to the end of the calendar year in which the Lease commences and thereafter for each successive calendar year (each, a “Lease Year”), or part thereof, Landlord shall send to Tenant a statement of projected increases in Recognized Expenses in excess of the Base Year and shall indicate what Tenant’s Share of Recognized Expenses shall be. The Base Year shall be adjusted to exclude from the Base Year “extraordinary items” incurred in such calendar year. For purposes or this subparagraph, extraordinary items shall mean either (X) cost increases over the prior calendar year of eleven and one quarter percent (11.25%) or more, or (Y) items which increase Landlord’s total expenses and such items have not been included in the determination of expenses by the Landlord (or the Landlord’s predecessor in interest) for the prior three years of operating the Building. As soon as administratively available, Landlord shall send to Tenant a statement of actual for Recognized Expenses for the prior Lease Year showing the Share due from Tenant. In the event the amount prepaid by Tenant exceeds the amount that was actually due then Landlord shall issue a credit to Tenant in an amount equal to the over charge, which credit Tenant may apply to future payments on account of Recognized Expenses until Tenant has been fully credited with the over charge. If the credit due to Tenant is more than the aggregate total of future rental payments, Landlord shall pay to Tenant the difference between the credit in such aggregate total. In the event Landlord has undercharged Tenant, then Landlord shall send Tenant an invoice with the additional amount due, which amount shall be paid in full by Tenant within thirty (30) days of receipt.

Tenant shall have the right, at its sole cost and expense, within ninety (90) days from receipt of Landlord’s statement of Recognized Expenses, to audit or have its appointed accountant audit Landlord’s records related to Recognized Expenses and Taxes provided that any such audit may not occur more frequently than once each calendar year nor apply to any year prior to the year of the statement being reviewed. In the event Tenant’s audit discloses any discrepancy, Landlord and Tenant shall use their best efforts to resolve the dispute and make an appropriate adjustment, failing which, they shall submit any such dispute to arbitration pursuant to the rules and under the jurisdiction of the American Arbitration Association in Philadelphia, Pennsylvania. The decision rendered in such arbitration shall be final, binding and non-appealable. The expenses of arbitration, other than individual legal and accounting expenses which shall be the respective parties’ responsibility, shall be divided equally between the parties. In the event, by agreement or as a result of an arbitration decision, it is determined that the actual Recognized Expenses and Taxes exceeded those claimed by the Landlord by more than six percent (6%), the actual, reasonable hourly costs to Tenant of Tenant’s audit (including legal and accounting costs) shall be reimbursed by Landlord. In the event Tenant utilizes a contingent fee auditor and Landlord is responsible for the payment of such auditor, Landlord shall only pay the reasonable hourly fee of such auditor

5. ELECTRICITY CHARGES . Landlord shall not be liable for any interruption any utility service for any reason unless caused by the gross negligence or willful misconduct of Landlord. Tenant shall pay to Landlord, as Additional Rent, within fifteen (15) business days of receipt of Landlord’s billing statement therefor, all charges incurred by Landlord for electricity, such charges to be based upon Tenant’s consumption, as measured by Landlord’s submeter for the Premises.

6. SIGNS; USE OF PREMISES AND COMMON AREAS . Landlord shall provide the original Tenant hereinabove named with standard identification signage on all Building directories and at the entrance to the

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Premises and shall replace the existing sign outside the Building with a sign of similar size and design to properly reflect the Tenant’s name and its designated affiliate. No other signs shall be placed, erected or maintained by Tenant at any place upon the Premises, Building or Project. Tenant’s use of the Premises shall be limited to general office use and storage incidental thereto (“Permitted Use”). The Permitted Use shall be subject to all applicable laws and governmental rules and regulations and to all reasonable requirements of the insurers of the Building Tenant shall not install in or for the Premises, any equipment which requires more electric current than is standard. Tenant shall have the right, non-exclusive and in common with others, to use (i) the exterior paved driveways and walkways of the Building for vehicular and pedestrian access to the Building, (ii) the internal common area, including elevators and (iii) the designated parking areas of the Project for the parking of automobiles of Tenant and its employees and business visitors; provided Landlord shall have the right in its sole discretion and from time to time, to construct, maintain, operate, repair, close, limit, take out of service, alter, change and modify all or any part of the common areas of the Project, including without limitation, reasonably restrict or limit Tenant’s utilization of the parking areas in the event the same become overburdened and in such case to equitably allocate on proportionate basis or assign parking spaces among Tenant and the other tenants of the Building.

7. ENVIRONMENTAL MATTERS . Tenant shall not generate, manufacture, refine, transport, treat, store, handle, dispose, bring or otherwise cause to be brought or permit any of its agents, employees, contractors or invitees to bring in, on or about any part of the Premises, Building or Project, any hazardous substance or hazardous waste in violation of applicable law.

8. TENANTS ALTERATIONS . Tenant will not cut or drill into or secure any fixture, apparatus or equipment or make alterations, improvements or physical additions (collectively, “Alterations”) of any kind to any part of the Premises without first obtaining the written consent of Landlord, such consent not to be unreasonably withheld. Notwithstanding anything in this Lease to the contrary, all furniture, movable trade fixtures and equipment (but not including telephone, security and communication equipment system wiring and cabling) installed by or for Tenant, its assignees or sublessees shall be removed by Tenant at the termination of this Lease.

9. ASSIGNMENT AND SUBLETTING . Tenant shall not, without the prior written consent of Landlord, assign this Lease or any interest herein or sublet the Premises or any part thereof. Any of the foregoing acts without such consent shall be void. If at any time during the Term Tenant desires to assign this Lease or sublet all or any part of the Premises, Tenant shall give notice to Landlord of such desire, including the name, address and contact party for the proposed assignee or subtenant, the effective date of the proposed assignment or sublease (including the proposed occupancy date by the proposed assignee or sublessee), and in the instance of a proposed sublease, the square footage to be subleased, a floor plan professionally drawn to scale depicting the proposed sublease area, and a statement of the duration of the proposed sublease (which shall in any and all events expire by its terras prior to the scheduled expiration of this Lease, and immediately upon the sooner termination hereof). Landlord may, at its option, exercisable by notice given to Tenant within forty-five (45) days next following Landlord’s receipt of Tenant’s notice, elect to recapture the Premises if Tenant is proposing to sublet more than twenty-five (25%) percent of the Premises or terminate this Lease in the event of an assignment. Regardless of Landlord’s consent, no subletting or assignment shall release Tenant of Tenant’s obligation or alter the primary liability of Tenant to pay the Rent and to perform all other obligations to be performed by Tenant hereunder for the remainder of the then current Lease Term. Landlord shall be entitled to a $250 fee for consenting to any sublet or assignment.

10. LANDLORD’S RIGHT OF ENTRY . Landlord and persons authorized by Landlord may enter the Premises at all reasonable times upon reasonable advance notice (or any time without notice in the case of an emergency). Landlord shall not be liable for inconvenience to or disturbance of Tenant by reason of any such entry; provided, however, that in the case of repairs or work, such shall be done, so far as practicable, so as to not unreasonably interfere with Tenant’s use of the Premises.

11. REPAIRS AND MAINTENANCE . Tenant, at its sole cost and expense, shall keep and maintain the Premises in good order and condition, free of rubbish, and shall promptly make all non-structural repairs necessary to keep and maintain such good order and condition. Tenant shall have the option of replacing lights, ballasts, tubes, ceiling tiles, outlets and similar equipment itself or it shall have the ability to advise Landlord of Tenant’s desire to have Landlord make such repairs. If requested by Tenant, Landlord shall make such repairs to the Premises within a reasonable time of notice to Landlord and shall charge Tenant for such services at Landlord’s standard rate (such rate to be competitive with the market rate for such services). When used in this Article 11 , the term “repairs” shall include replacements and renewals when necessary. All repairs made by Tenant or Landlord shall utilize materials and equipment which are at least equal in quality and usefulness to those originally used in constructing the Building and the Premises. Landlord shall provide the janitorial services for the Premises set forth on Exhibit “C” .

12. INSURANCE; SUBROGATION RIGHTS . Tenant shall obtain and keep in force at all times during the term hereof, at its own expense, commercial general liability insurance including contractual liability and personal injury liability and all similar coverage, with combined single limits of $2,000,000.00 on account of bodily injury to or death of one or more persons as the result of any one accident or disaster and on account of damage to property. Tenant shall also require its movers to procure and deliver to Landlord a certificate of insurance naming Landlord as an additional insured. Tenant shall, at its sole cost and expense, maintain in full force and effect on all Tenant’s trade fixtures, equipment and personal property on the Premises, a policy of “special form” property insurance covering the full replacement value of such property. All liability insurance required hereunder shall not be subject to cancellation without at least thirty (30) days prior notice to all insureds, and shall name Tenant as

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insured and Landlord and Brandywine Realty Trust as additional insureds, and, if requested by Landlord, shall also name as an additional insured any mortgagee or holder of any mortgage which may be or become a lien upon any part of the Premises. Prior to the commencement of the Term, Tenant shall provide Landlord with certificates which evidence that the coverages required have been obtained for the policy periods. Tenant shall also furnish to Landlord throughout the Term replacement certificates at least thirty (30) days prior to the expiration dates of the then current policy or policies. All the insurance required under this Lease shall be issued by insurance companies authorized to do business in the Commonwealth of Pennsylvania with a financial rating of at least an A-X as rated in the most recent edition of Best’s Insurance Reports and in business for the past five years. The limit of any such insurance shall not limit the liability of Tenant hereunder. If Tenant fails to maintain such insurance, Landlord may, but is not required to, procure and maintain the same, at Tenant’s expense to be reimbursed by Tenant as Additional Rent within ten (10) days of written demand. Any deductible under such insurance policy in excess of Twenty Five Thousand ($25,000) must be approved by Landlord in writing prior to issuance of such policy. Tenant shall not self-insure without Landlord’s prior written consent Each party hereto, and anyone claiming through or under them by way of subrogation, waives and releases any cause of action it might have against the other party and Brandywine Realty Trust and their respective employees, officers, members, partners, trustees and agents, on account of any loss or damage that is insured against under any insurance policy required to be obtained hereunder. Each party agrees that it will use its best efforts to cause its insurance carrier to endorse all applicable policies waiving the carrier’s right of recovery under subrogation or otherwise against the other party.

13. INDEMNIFICATION . Tenant shall defend, indemnify and hold harmless Landlord, Brandywine Realty Trust and their respective employees and agents from and against any and all third-party claims, actions, damages, liability and expense (including all reasonable attorney’s fees, expenses and liabilities incurred in defense of any such claim or any action or proceeding brought thereon) arising from any activity, work or things done, permitted or suffered by Tenant or its agents, licensees or invitees in or about the Premises, the Building or the Project contrary to the requirements of this Lease, and any negligence or willful act of Tenant or any of Tenant’s agents, contractors, employees or invitees. Without limiting the generality of the foregoing, Tenant’s obligations shall include any case in which Landlord or Brandywine Realty Trust shall be made a party to any litigation commenced by or against Tenant, its agents, subtenants, licensees, concessionaires, contractors, customers or employees, in which case Tenant shall defend, indemnify and hold harmless Landlord and Brandywine Realty Trust and shall pay all costs, expenses and reasonable attorney’s fees incurred or paid by Landlord and Brandywine Realty Trust in connection with such litigation, after notice to Tenant and Tenant’s refusal to defend such litigation, and upon notice from Landlord shall defend the same at Tenant’s expense by counsel reasonably satisfactory to Landlord.

14. FIRE DAMAGE . If (i) the casualty damage is of a nature or extent that, in Landlord’s reasonable judgment, the repair and restoration work would require more than two hundred ten (210) consecutive days to complete after the casualty (assuming normal work crews not engaged in overtime), or (ii) more than thirty (30%) percent of the total area of the Building is extensively damaged, or (iii) the casualty occurs in the last Lease Year of the Term and Tenant has not exercised a renewal right or (iv) insurance proceeds are unavailable or insufficient, either party shall have the right to terminate this Lease and all the unaccrued obligations of the parties hereto, by sending written notice of such termination to the other within thirty (30) days of the date of casualty. Such notice is to specify a termination date no less than fifteen (15) days after its transmission. In the event of damage or destruction to the Premises or any part thereof as set forth in subsections (i), (ii) or (iii) above and neither party has terminated this Lease, Tenant’s obligation to pay Fixed Rent and Additional Rent shall be equitably adjusted or abated for such time as the Premises is not capable of being used by Tenant for its Permitted Use.

15. SUBORDINATION; RIGHTS OF MORTGAGEE . This Lease shall be subordinate at all times to the lien of any mortgages now or hereafter placed upon the Premises, Building and/or Project and land of which they are a part without the necessity of any further instrument or act on the part of Tenant to effectuate such subordination. Tenant further agrees to execute and deliver within ten (10) day of demand such further instrument evidencing such subordination and attornment as shall be reasonably required by any mortgagee. If Landlord shall be or is alleged to be in default of any of its obligations owing to Tenant under this Lease, Tenant shall give to the holder of any mortgage (the “Mortgagee”) now or hereafter placed upon the Premises, Building and/or Project, notice by overnight mail of any such default which Tenant shall have served upon Landlord. Tenant shall not be entitled to exercise any right or remedy as there may be because of any default by Landlord without having given such notice to the Mortgagee. If Landlord shall fail to cure such default, the Mortgagee shall have forty-five (45) additional days within which to cure such default.

16. CONDEMNATION . If in Landlord’s reasonable judgement a taking renders the Building unsuitable at Landlord’s option, this Lease shall, at either party’s option, terminate as of the date title to the condemned real estate vests in the condemnor, and the Rent herein reserved shall be apportioned and paid in full by Tenant to Landlord to that date and all rent prepaid for period beyond that date shall forthwith be repaid by Landlord to Tenant and neither party shall thereafter have any liability hereunder. If this Lease is not terminated after any such taking or condemnation, the Fixed Rent and the Additional Rent shall be equitably reduced in proportion to the area of the Premises which has been taken for the balance of the Term. Tenant shall have the right to make a claim against the condemnor to the extent that such claim does not reduce the sums otherwise payable by the condemnor to Landlord.

17. ESTOPPEL CERTIFICATE . Each party agrees at any time and from time to time, within ten (10) days after the other party’s written request, to execute and deliver to the other party a written instrument in recordable form certifying all information reasonably requested.

18. DEFAULT . If: Tenant fails to pay any installment of Rent when due; provided, however, Landlord shall provide written notice of the failure to pay such Rent and Tenant shall have a three (3) business day

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grace period from its receipt of such Landlord’s notice within which to pay such Rent without creating a default hereunder. The late fee set forth in Article 3 hereof shall be due on the first day after such payment is due irrespective of the foregoing notice and grace period; Tenant “vacates” the Premises (other than in the case of a permitted subletting or assignment) or permits the same to be unoccupied; Tenant fails to bond over a construction or mechanics lien within ten (10) days of demand; Tenant fails to observe or perform any of Tenant’s other non-monetary agreements or obligations herein contained within ten (10) days after written notice specifying the default, or the expiration of such additional time period as is reasonably necessary to cure such default, provided Tenant immediately commences and thereafter proceeds with all due diligence and in good faith to cure such default; then, in any such event, an “Event of Default” shall be deemed to exist and Tenant shall be in default hereunder.

If an Event of Default shall occur, the following provisions shall apply and Landlord shall have, in addition to all other rights and remedies available at law or in equity, including the right to terminate the Lease, the rights and remedies set forth herein, which may be exercised upon or at any time following the occurrence of an Event of Default. 1. Acceleration of Rent . By notice to Tenant, Landlord shall have the right to accelerate all Rent and all expense due hereunder and otherwise payable in installments over the remainder of the Term; and the amount of accelerated rent to the termination date, without further notice or demand for payment, shall be due and payable by Tenant within five (5) days after Landlord has so notified Tenant, such amount collected from Tenant shall be discounted to present value using an interest rate of six percent (6%) per annum. Additional Rent which has not been included, in whole or in part, in accelerated rent, shall be due and payable by Tenant during the remainder of the Term, in the amounts and at the times otherwise provided for in this Lease. 2. Landlord’s Damages . The damages which Landlord shall be entitled to recover from Tenant shall be the sum of: (i) all Fixed Rent and Additional Rent accrued and unpaid as of the termination date; and (ii)(a) all reasonable costs and expenses incurred by Landlord in recovering possession of the Premises, including actual legal fees, and removal and storage of Tenant’s property, (ii)(b) the reasonable costs and e