Exhibit 10.2

SEVENTH AMENDMENT TO

SENIOR FIRST PRIORITY SECURED PROMISSORY NOTE

This SEVENTH AMENDMENT TO SENIOR FIRST PRIORITY SECURED PROMISSORY NOTE (this “Seventh Amendment”) is made as of December 10, 2013 by and between Prospect Global Resources, Inc., a Delaware corporation (“Maker”), and the Karlsson Group, Inc., an Arizona corporation (“Holder”), with respect to the following facts:

RECITALS

WHEREAS, Maker issued to Holder that certain Senior First Priority Secured Promissory Note dated August 1, 2012 (the “Original Note”), whereby the Maker promised to pay to Holder the principal sum of One Hundred Twenty-Five Million Dollars ($125,000,000);

WHEREAS, American West Potash, LLC, a Delaware limited liability company (“AWP”), Prospect Global Resources, Inc., a Nevada corporation (“Prospect Nevada”), Apache County Land & Ranch, LLC, a Nevada limited liability company (“Apache”), Maker and Holder entered into that certain Extension Agreement (the “Extension Agreement”) dated as of April 15, 2013;

WHEREAS, Maker and Holder entered into an Amendment to Senior First Priority Secured Promissory Note dated April 15, 2013 (“First Amendment” and the Original Note as amended thereby and as otherwise amended, restated or modified from time to time, the “Note”);

WHEREAS, AWP, Prospect Nevada, Apache, Maker and Holder entered into that certain Second Extension Agreement dated as of June 26, 2013;

WHEREAS, Maker and Holder entered into a Second Amendment to Senior First Priority Secured Promissory Note dated as of June 26, 2013;

WHEREAS, Maker and Holder entered into a Third Amendment to Senior First Priority Secured Promissory Note dated as of September 9, 2013;

WHEREAS, Maker and Holder entered into a Fourth Amendment to Senior First Priority Secured Promissory Note dated as of September 13, 2013;

WHEREAS, Maker and Holder entered into a Fifth Amendment to Senior First Priority Secured Promissory Note dated as of November 13, 2013;

WHEREAS, Maker and Holder entered into a Sixth Amendment to Senior First Priority Secured Promissory Note dated as of December 3, 2013;

WHEREAS, AWP, Prospect Nevada, Apache, Maker and Holder entered into that certain Fourth Extension Agreement (the “Fourth Extension Agreement”) dated as of December 10, 2013; and

WHEREAS, it is a condition to the effectiveness of the Fourth Extension Agreement that Maker and Holder modify the Note.

NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Maker and Holder hereby agree as follows:

AGREEMENT

1.                                      Defined Terms.  All capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the Note.

2.                                      Amendments.

(a)                                 Amendment to Section 2.2.  Section 2.2 of the Note is amended and restated to read in its entirety as follows:

“Payments Other Than Interest or Principal.  Maker shall pay to Holder, designating in writing such payments as payments under this section of this Note, the following amounts, as additional consideration for the Holder’s sale of its membership interest in American West Potash, LLC under the Purchase Agreement and not as prepayments of principal under this Note, (i) a payment equal to the 2012 453A Amount on or before the Initial 453A Payment Date, (ii) a payment equal to the 2013 453A Amount on or before the Initial 453A Payment Date, (iii) a payment equal to the 2014 453A Amount on or before February 10, 2015, and, (iv) along with each payment of principal pursuant to Section 3.2 of this Note, and at the Maturity Date, the Principal Payment Tax Gross-Up Amount or amount due under Section 3.5 with respect to such payment; provided, however, that no Principal Payment Tax Gross-Up Amount or amount under Section 3.5 shall be due with respect to the first $200,000 of pre-payments under Section 3.2(a).  For purposes hereof, the “Initial 453A Payment Date” shall mean the earlier of (i) March 10, 2014; and (ii) the date of occurrence of the first Event of Default to occur under this Note on or after November 14, 2013.  For the avoidance of doubt, no payment made pursuant to any other provision of this Note, including but not limited to Section 3.2(c) hereof, shall satisfy in whole or any part Maker’s obligation to make the payments set forth in this Section 2.2.”

(b)                                 Amendment to Section 3.2(c).  Section 3.2(c) of the Note is amended by adding the following sentence at the end thereof:

“Notwithstanding anything herein to the contrary, the ten percent (10%) prepayment requirement set forth in this Section 3.2(c) shall not apply to the first $1,000,000 in Qualified Financings (such initial $1,000,000 in Qualified Financings, the “Winter 2013/14 Qualified Financings”) that Prospect Nevada arranges on or after December 10, 2013 and of which it receives the proceeds on or before March 10, 2014.”

(c)                                  Addition of Section 3.4.  Section 3.4 of the Note, previously deleted by the First Amendment, is inserted into the Note in the following form:

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“Prepayment Discount.  In the event that Maker makes payments under the Note totaling Twenty-Five Million Dollars ($25,000,000) on or after December 10, 2013 and on or before March 10, 2014, whether through one or multiple payments, and whether pursuant to Section 2.2, Section 3.2 or Section 3.3, then all of Maker’s obligations under this Note shall be deemed to have been satisfied in full by Maker as of the date of such payment, or, in the case of multiple payments, the date on which the last such payment is made.”

(d)                                 Amendment to Section 5.6.  Section 5.6 of the Note is amended to read in its entirety as follows:

5.6                               “Failure of Parent to Fund Escrow.  Prospect Nevada shall fail, for any reason, to deposit into the escrow account established pursuant to the Escrow Agreement (the “Escrow Account”):  (A) $2,000,000 from the Roth Offering (as defined in the Second Extension Agreement) within two (2) business days of receipt of funds from the Roth Offering; (B) from the proceeds of any Qualified Financing (other than the Roth Offering, the Fall 2013 Qualified Financings, or the Winter 2013/14 Qualified Financings), within one (1) business day of receipt of the funds raised in such Qualified Financing, fifty percent (50%) of the proceeds of any Qualified Financing net of third party payments in satisfaction of transaction expenses or fees/commissions in connection with such Qualified Financing in an amount not to exceed the Funding Expense Cap (as defined in that certain Second Extension Agreement dated as of June 26, 2013 among Maker, Holder and the other parties thereto (the “Second Extension Agreement”)); or (C) from the proceeds of the Fall 2013 Qualified Financings, within one (1) business day of receipt of funds from such Qualified Financings, the lesser of (i) $300,000, and (ii) fifty percent (50%) of the proceeds of such Qualified Financings net of third party payments in satisfaction of transaction expenses or fees/commissions in connection with such Qualified Financings in an amount not to exceed the Funding Expense Cap, until such time as deposits aggregating $12,000,000 have been made into the Escrow Account on or after June 26, 2013.”

(e)                                  New Section 5.13.  The following new Section 5.13 is hereby added after Section 5.12 of the Note:

5.13                        “Section 3.4 Prepayment.  Maker shall not have prepaid the Note in the full amount of Twenty-Five Million Dollars ($25,000,000) on or after December 10, 2013 and on or before March 10, 2014 in accordance with Section 3.4 of the Note.”

(f)                                   Amendment to Section 8.7.  Section 8.7 of the Note is hereby amended to read in its entirety as follows:

8.7                               “Successors and Assigns.  This Note shall be binding upon and shall inure to the benefit of the Parties and their respective successors and permitted assigns.  Maker may not assign its rights or obligations hereunder without the prior written

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consent of Holder.  Holder may, without the consent of any Person, assign the Note and/or the Loan Documents, in whole or in part, to any Person notwithstanding anything to the contrary in the Loan Documents or the Membership Interest Purchase Agreement dated as of May 30, 2012, including, without limitation, the confidentiality and covenant not to compete undertakings contained therein, and Holder (or any shareholder, director, agent, employee or officer of Holder) may actively solicit purchasers of the Note, as more fully set forth in Section 19 of the Fourth Extension Agreement, as defined below.  Maker agrees that, for purposes of this Agreement, an “assignment” shall be deemed to include, but not be limited to, a sale, a contribution to a new or existing entity (including, but not limited to, a joint venture of which Holder or any affiliate of Holder is a member) or an exchange with any such entity, or any other transfer for any medium of value, including, without limitation, equity securities, royalty interests, property rights or any form of contingent consideration and notwithstanding whether such assignment is effected in a private sale or under judicial supervision.  Notwithstanding the generality of the foregoing, (i) it shall be a condition precedent to any assignment of this Note as a result of which there will be multiple simultaneous holders of the Note and/or the related rights under the Loan Documents that such holders shall have put in place, between or among themselves, a written agreement (an “Agency Agreement”), which includes agency provisions pursuant to the terms of which a single administrative agent (the “Administrative Agent”) is appointed, with which Maker and its affiliates will solely interface with respect to all rights and obligations under the Note and the Loan Documents, and to which Maker and its affiliates will remit all payments hereunder, and which Agency Agreement will provide for the Administrative Agent to provide Maker with a copy of the Agency Agreement, and any amendments thereto, upon execution of the same; and (ii) it shall be a condition precedent to any assignment of this Note that any assignee thereof agree to be bound by Sections 5(b)(3)-(5) of that certain Fourth Extension Agreement dated as of December 10, 2013 by and among Maker, Holder, Prospect Nevada, Company and Apache (the “Fourth Extension Agreement”).”

3.                                      Miscellaneous.

(a)                                 No Other Amendment.  Except as expressly amended in this Seventh Amendment, all provisions of the Note shall remain in full force and effect, and the parties thereto and hereto shall continue to have all their rights and remedies under the Note.  In the event of a conflict between the terms and provisions of this Seventh Amendment and the terms and conditions of the Note, the provisions of this Seventh Amendment shall govern.

(b)                                 Relation to Note.  This Seventh Amendment constitutes an integral part of the Note.  Upon the effectiveness of this Seventh Amendment, each reference in the Note to “this Promissory Note,” “hereunder,” “hereof,” or words of like import referring to the Note, shall mean and be a reference to the Note as amended hereby.

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(c)                                  Successors and Assigns.  This Seventh Amendment shall be binding on and shall inure to the benefit of the parties hereto and their respective successors and assigns except as otherwise provided herein.

(d)                                 Counterparts.  This Seventh Amendment may be executed by the parties hereto on any number of separate counterparts, any of which may be executed and transmitted by facsimile, and each of which shall be deemed an original and all of which, taken together, shall be deemed to constitute one and the same instrument.

IN WITNESS WHEREOF, the parties hereto have caused this Seventh Amendment to be executed and delivered as of the date first above written.

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