Exhibit 10.5

SECOND AMENDMENT TO SALE AND PURCHASE AGREEMENT

This Second Amendment to the Sale and Purchase Agreement (“Second Amendment”) is
dated as of March 20, 2008, between CITGO Asphalt Refining Company, a New Jersey
general partnership, with offices at 1293 Eldridge Parkway, Houston, Texas 77077
(“Seller”) and NuStar Asphalt Refining, LLC, a Delaware limited liability
company, with offices at 2330 North Loop 1604 West, San Antonio, Texas 78248
(“Buyer”).

WHEREAS, Seller and Buyer entered into that certain Sale and Purchase Agreement
dated as of November 5, 2007, as amended (the “Purchase Agreement”);

WHEREAS, all capitalized terms used but not defined herein shall have their
respective meanings set forth in the Purchase Agreement; and

WHEREAS, Seller and Buyer desire to modify certain provisions of the Purchase
Agreement;

NOW, THEREFORE, Seller and Buyer agree as follows:

1. Amendment.

(a) Section 3.8(a) of the Seller Disclosure Schedule of the Purchase Agreement
regarding Material Contracts is hereby amended and replaced with Exhibit A
attached hereto.

(b) Section 3.11 of the Seller Disclosure Schedule of the Purchase Agreement
regarding environmental issues is hereby amended and replaced with Exhibit B
attached hereto.

(c) Section 3.12 of the Seller Disclosure Schedule of the Purchase Agreement
regarding pending or threatened Litigation is hereby amended and replaced with
Exhibit C attached hereto.

(d) Section 3.18 of the Seller Disclosure Schedule of the Purchase Agreement
regarding customer and supplier relations is hereby amended and replaced with
Exhibit D attached hereto.

(e) Section 3.21 of the Seller Disclosure Schedule of the Purchase Agreement
regarding insurance is hereby amended and replaced with Exhibit E attached
hereto.

(f) Section 3.22 of the Seller Disclosure Schedule of the Purchase Agreement
regarding Assumed Contracts is hereby amended and replaced with Exhibit F
attached hereto.

(g) Schedule 2.1(e) of the Purchase Agreement regarding rolling stock is hereby
amended and replaced with Exhibit G attached hereto.

(h) Schedule 2.4(a) of the Purchase Agreement regarding Seller third person
consents and authorizations is hereby amended and replaced with Exhibit H
attached hereto.

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(i) Schedule 2.5 of the Purchase Agreement regarding Inventory is hereby amended
and replaced with Exhibit I attached hereto.

(j) Schedule 2.7(c) of the Purchase Agreement regarding Specific Retained
Obligations is hereby amended and replaced with Exhibit J attached hereto.

(k) Schedule 5.1 of the Purchase Agreement regarding Operation of the Business
is hereby amended and replaced with Exhibit K attached hereto.

(l) Schedule 6.1 of the Purchase Agreement regarding Employees is hereby amended
and replaced with Exhibit L attached hereto.

(m) Schedule 6.2(a) of the Purchase Agreement regarding employment offers is
hereby amended and replaced with Exhibit M attached hereto.

(n) Schedule 8.3(g) of the Purchase Agreement regarding Necessary Third-Party
Consents and Authorizations is hereby amended and replaced with Exhibit N
attached hereto.

2. Miscellaneous.

(a) Except as expressly set forth herein, the Purchase Agreement shall remain in
fill force and effect and is hereby in all respects ratified and confirmed.

(b) The Purchase Agreement, as amended by this Second Amendment, sets forth the
entire understanding of Seller and Buyer with respect to the subject matter
thereof and hereof.

(c) This Second Amendment shall be governed by and construed under the laws of
the State of Texas applicable to agreements made and to be performed entirely
within the State of Texas, without giving effect to any of its principles of
conflicts of laws which would require the application of the laws of another
jurisdiction.

(d) This Second Amendment may be executed in any number of counterparts, each of
which shall be an original and all of which shall constitute one and the same
document.

(e) For purposes of Section l0.2(c)(i) of the Purchase Agreement, the parties
hereto agree that any Losses Buyer suffers or incurs as a result of any matters
disclosed in the amendments to the Seller Disclosure Schedule of the Purchase
Agreement made pursuant to Sections 1(a), (b), (c), (d), (e) and (f) of this
Amendment shall constitute Permitted Schedule Update Losses.

(f) On January 10, 2008, Seller and Buyer entered into that certain Services and
Indemnity Agreement under which, among other things, Seller agreed to indemnify
Buyer against any and all Claims or Losses arising out of or related to the Cape
May Agreements, or the Cape May Arbitration (as such terms are defined in the
Services and Indemnity Agreement). Seller and Buyer acknowledge and agree that
the rights of Buyer under or pursuant to the Services and Indemnity Agreement
shall not be limited or prejudiced in any way by the

 

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identification of the Cape May Agreements on Exhibit B (Permitted Exceptions) to
the deed conveying the Paulsboro Refinery from Seller to Buyer to be delivered
at Closing.

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IN WITNESS WHEREOF, the parties hereto have executed this Second Amendment
effective as of the date first above written.

 

CITGO ASPHALT REFINING COMPANY By:  

CITGO PETROLEUM CORPORATION,

General Partner

 

By:   /s/ Philip J. Reedy

Name:   Philip J. Reedy Title:   Vice President, Finance

 

By:  

CITGO East Coast Oil Corporation,

General Partner

 

By:   /s/ Dean Hasseman

Name:   Dean Hasseman Title:   Assistant Secretary

 

NUSTAR ASPHALT REFINING, LLC By:   /s/ Michael H. Hoeltzel

Name:   Michael H. Hoeltzel Title:   Senior Vice President

 

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