Exhibit 10.18

SECURED PROMISSORY NOTE

 

$12,000,000

November __, 2006

FOR VALUE RECEIVED, the undersigned, Sonoran Energy, Inc., a Washington
corporation (the “Borrower”), promises to pay to the order of NGP CAPITAL
RESOURCES COMPANY (the “Lender”) on February [__], 2008, the principal sum of
TWELVE MILLION DOLLARS ($12,000,000) or, if less, the aggregate unpaid principal
amount of all Loans shown on the schedule attached hereto (and any continuation
thereof) made by the Lender pursuant to that certain Credit Agreement, dated as
of November[__], 2006 (together with all amendments and other modifications, if
any, from time to time thereafter made thereto, the “Credit Agreement”), among
the Borrower, certain institutional lenders and the Lender and NGPC Asset
Holdings, LP, as administrative agent (the “Administrative Agent”).

The Borrower also promises to pay interest on the unpaid principal amount hereof
from time to time outstanding from the date hereof until maturity (whether by
acceleration or otherwise) and, after maturity, until paid, at the rates per
annum and on the dates specified in the Credit Agreement.

Payments of both principal and interest are to be made in lawful money of the
United States of America in same day or immediately available funds to the
account designated by the Administrative Agent pursuant to the Credit Agreement.

This Note is one of the Notes referred to in, and evidences Indebtedness
incurred under, the Credit Agreement, to which reference is made for a
description of the security for this Note and for a statement of the terms and
conditions on which the Borrower is permitted and required to make prepayments
and repayments of principal of the Indebtedness evidenced by this Note and on
which such Indebtedness may be declared to be immediately due and payable.
 Unless otherwise defined, terms used herein have the meanings provided in the
Credit Agreement.

Except for notices to the Borrower as required by Section 11.2 of the Credit
Agreement, all parties hereto, whether as makers, endorsers, or otherwise,
severally waive presentment for payment, demand, protest and notice of dishonor.

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THIS NOTE HAS BEEN DELIVERED IN HOUSTON, TEXAS AND SHALL BE DEEMED TO BE A
CONTRACT MADE UNDER AND GOVERNED BY THE INTERNAL LAWS OF THE STATE OF NEW YORK
WITHOUT GIVING EFFECT TO THE PRINCIPLES THEREOF RELATING TO CONFLICTS OF LAW
(EXCEPT SECTION 5-1401 OF THE NEW YORK GENERAL OBLIGATIONS LAW).

SONORAN ENERGY, INC.,
a Washington corporation

By:

 

Name:

 

Title:

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LOANS AND PRINCIPAL PAYMENTS

Date

Amount of Loan Made
_____

Rate
______

Amount of Principal Repaid
_________________

Unpaid Principal Balance
_____________

Total

Notation
Made By

 

Interest Period

LIBO RATE

LIBO RATE