Irrevocable Standby Letter

Exhibit 10.16

Date: May 19, 2003

With a Copy To:

U.S. Bank, N.A.

Attn: Commercial Real Estate Division

425 Walnut Street, 10^th Floor

CN-OH-W10C

Cincinnati, OH 45202

LADIES/GENTLEMEN:

We hereby issue our Irrevocable Standby Letter of Credit (“Letter of Credit”) in your favor.  This Letter of Credit is available by sight payment with ourselves only against presentation to this office at the above address of the following documentation:

1.          Beneficiary’s sight draft drawn on us marked: “Drawn under Union Bank of California, N.A., Irrevocable Standby Letter of Credit No.       , dated May 19, 2003.”

2.          A dated statement purportedly signed by an authorized representative or officer of the Beneficiary stating:

(a)           “The undersigned being a duly authorized representative or officer of SCP Park Meadows, LLC (“Landlord”) hereby represents and warrants that the amount drawn hereby is owed to Landlord by Revcare, Inc. (“Tenant”) because Tenant has failed to perform in accordance with the Lease agreement dated               , (the “Lease”) between Landlord and the Tenant, and any periods, as provided in said Lease, have expired without such failure to comply having been remedied or cured.”

Partial drawings are permitted.

This Letter of Credit is transferable successively in its entirety only up to the then available amount in favor of any nominated transferee (“Transferee”), assuming such transfer to such Transferee would be in compliance with then applicable law and regulation, including but not limited to the regulations of the U.S. Department of Treasury and U.S. Department of Commerce.  At the time of transfer, the original Letter of Credit and original Amendment(s), if any must be surrendered to us together with our Letter of Transfer documentation (in the form of Annex A attached hereto) duly executed, and payment of our transfer commission.

Irrevocable Standby Letter of Credit No.                  

This Letter of Credit shall be deemed automatically extended without an amendment for a one year period beginning on the present expiration date hereof May 19, 2004 and upon each anniversary of such date, unless at least 60 (Sixty) days prior to any such expiration date we have sent you written notice by courier service or overnight mail that we elect not to permit this Letter of Credit to be so extended beyond its then current expiration date.  No presentation made under this Letter of Credit after such expiry date will be honored.

This Letter of Credit shall finally expire on April 30, 2006, if it has not previously expired in accordance with the preceding sentence.

The date this Letter of Credit expires in accordance with the above provision is the “Final Expiry Date.”  Upon the occurrence of the Final Expiry Date this Letter of Credit shall fully and finally expire and no presentations made under this Letter of Credit after such date will be honored.

Upon receipt by you of your notice that we elect not to renew, you may draw against presentation to our office at the address above of the following documentation:

1.                          A sight draft drawn on us, purportedly signed by an authorized representative or officer of the Beneficiary, marked:  “Drawn under Union Bank of California.  N.A., Irrevocable Standby Letter of Credit No.       , dated May 19, 2003.”

2.                          A dated statement purportedly signed by an authorized representative or officer of the Beneficiary stating:  “The undersigned being a duly authorized representative or officer of SCP Park Meadows, LLC, hereby represents and warrants that Revcare, Inc. has failed to provide an acceptable substitute Letter of Credit at least twenty (20) days prior to expiration of Union Bank of California, N.A. Irrevocable Standby Letter of Credit No.        .”

This Letter of Credit sets forth in full the terms of our undertaking, and such terms shall not be modified, amended or amplified by any document, instrument or agreement referred to in this Letter of Credit, in which his Letter of Credit is referred to or to which this Letter of Credit relates.

Except as stated herein, this Letter of Credit is not subject to any condition of qualification and is our individual obligation which is in no way contingent upon reimbursement.

SPECIAL INSTRUCTIONS:

The original of this Letter of Credit must be presented together with the above documents in order to endorse the amount of each drawing on the reverse side.

All banking charges under this Letter of Credit except remittance wire fee of USD35.00 are for the account of the applicant.

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We hereby agree with you that drafts drawn under and in compliance with the terms of this Letter of Credit will be duly honored upon presentation and delivery to Union Bank of California, N.A., at the address above.  Documents are to be sent in one lot by courier service, overnight mail or hand delivery.

This Letter of Credit is subject to the “Uniform Customs and Practice for Documentary Credits (1993 Revision)”,  International Chamber of Commerce Publication No. 500.

Union Bank of California, N.A.

Trade Service Operations

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Annex A

LETTER OF CREDIT TRANSFER INSTRUCTIONS

UNION BANK OF CALIFORNIA, N.A.

SOUTHERN CALIFORNIA

TRADE SERVICES OPERATIONS

1980 Saturn Street, V01-519

Monterey Park, California ###-###-####

Date:                  May 19, 2003

Re:                               Union Bank of California, N.A. Irrevocable Standby Letter of Credit No.         dated May 19, 2003.”

Ladies and Gentlemen:

For value received, the undersigned beneficiary [Insert Name of Beneficiary]

                                      (the “Beneficiary”) hereby irrevocably transfers to :

(the “Transferee”) all rights of Beneficiary to draw under the above letter of credit (“Letter of Credit”) and Transferee shall have sole rights as beneficiary thereof, including without limitation sole rights relating to any amendments thereto, whether increases or extensions or other amendments and whether now existing or hereafter made, in connection with the foregoing.  Beneficiary hereby irrevocably agrees and instructs you (a) that Beneficiary does not retain any right to refuse to allow you to advise to Transferee any amendment to the Letter of Credit, (b) that all future amendments to the Letter of Credit are to be advised directly to Transferee without necessity of any consent of or notice to Beneficiary, and (c) that there will be no substitution of Beneficiary’s draft(s) and/or other documents for those presented to you by Transferee.

Beneficiary hereby certifies that transferee is the owner of, or is lending on the security of the following property: [Insert street address of property before issuance of the letter of credit]

We enclose herewith the original Letter of Credit (and all original amendments thereto dated on or prior to the date of these Transfer Instructions) and, together with Transferee, request that you transfer the Letter of Credit to Transferee by reissuing the Letter of Credit in favor of the Transferee with provisions consistent with the Letter of Credit.

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Enclosed is our remittance in the amount of USD               representing your transfer commission in accordance with our published schedule of charges currently in effect.  In addition, we agree to pay to you on demand any expenses that may be incurred in connection with this transfer.

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