SECOND AMENDMENT TO LIMITED PARTNERSHIP AGREEMENT OF KILGORE PARTNERS, L.P. A Utah Limited Partnership

Exhibit 3.72

SECOND AMENDMENT TO LIMITED PARTNERSHIP AGREEMENT

OF

XXXXXXX PARTNERS, L.P.

A Utah Limited Partnership

This Second Amendment to Limited Partnership Agreement of XXXXXXX PARTNERS, L.P. (“Second Amendment”), is made effective as of January 3, 2016 is executed and agreed to by (i) Summit Materials, LLC, a Delaware limited liability company, as a “General Partner” and “Limited Partner”; (ii) B & B Resources, Inc. a Utah corporation, as a “Limited Partner”; (iii) Xxxxx & Xxxxx, Inc., a Wyoming corporation, as a “Limited Partner”; (iv) XxXxxxx Xxxxxxx Construction Co, a Utah corporation, as a “Limited Partner” and (v) Xxxx Construction, Inc., a Colorado corporation, as a “Limited Partner.”

RECITALS:

WHEREAS, effective as of the 1st day of June, 2015, the Members of the Company entered into an Amended and Restated Limited Partnership Agreement which was subsequently amended with the First Amendment to Limited Partnership Agreement of Xxxxxxx Partners, L.P. on August 21, 2015 (together, the “Partnership Agreement”);

WHEREAS, the Members of the Company desire to enter into this Second Amendment in order to reflect the addition of Xxxx Construction, Inc.. as a limited partner, and its capital contribution to the Partnership.

NOW, THEREFORE, in consideration of mutual covenants, conditions and agreements herein contained, the Parties hereby agree as follows:

1. Section 2.6.2 is deleted in its entirety and replaced with the following:

2.6.2. Limited Partner. The names and addresses of the Limited Partners are:

Name		Address
Summit Materials, LLC		0000 Xxxxxxx, 0xx Xxxxx
		Xxxxxx, XX 00000
B & B Resources, Inc.		0000 Xxxxxxx, 0xx Xxxxx
		Xxxxxx, XX 00000
Xxxxx & Xxxxx, Inc.		0000 Xxxxxxx, 0xx Xxxxx
		Xxxxxx, XX 00000
XxXxxxx Xxxxxxx Construction Co		0000 Xxxxxxx, 0xx Xxxxx
		Xxxxxx, XX 00000
Xxxx Construction, Inc.		0000 Xxxxxxx, 0xx Xxxxx
		Xxxxxx, XX 00000

2. Schedule A to the Partnership Agreement is replaced with the following:

SCHEDULE A

(Attached to and forming part of Limited Partnership Agreement)

INITIAL CAPITAL CONTRIBUTIONS

				Agreed Value of Initial
Partner		Initial Capital Contribution		Capital Contribution
Summit Materials, LLC		Management services; All of the net		$	164,872,000.00
		assets of its wholly-owned
		subsidiary, Xxxxxxx Companies,
		LLC, as described in the
		Assignment and Assumption
		Agreement and Xxxx of Sale at
		Exhibit A
B & B Resources, Inc.		All of the net assets of B&B		$	5,000,000.00
		Resources, Inc. as described in the
		Assignment and Assumption
		Agreement and Xxxx of Sale at
		Exhibit B
Xxxxx & Xxxxx, Inc.		All of the net assets of Xxxxx &		$	15,860,000.00
		Xxxxx, Inc. as described in the
		Assignment and Assumption
		Agreement and Xxxx of Sale at
		Exhibit C
XxXxxxx Xxxxxxx		All of the net assets of XxXxxxx		39,855,000.00
Construction Co		Xxxxxxx Construction Co. as
		described in the Assignment and
		Assumption Agreement and Xxxx of
		Sale at Exhibit X
Xxxx Construction, Inc.		All of the net assets of Xxxx		$	42,121,000.00
		Construction, Inc. as described in
		the Assignment and Assumption
		Agreement and Xxxx of Sale at
		Exhibit E
		Total		$	267,708,000.00

3. Ratification. Except as expressly amended hereby, the Partnership Agreement is hereby confirmed and ratified in all respects.

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[Signatures follow on the next page]

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IN WITNESS WHEREOF, the Parties have executed this Second Amendment to be effective as of the date first written above.

General Partner:

Summit Materials, LLC

/s/ Xxxx Xxx Xxxxxxxx

Xxxx Xxx Xxxxxxxx, Secretary

Limited Partners:

Summit Materials, LLC

/s/ Xxxxx Xxxxxxx

Xxxxx Xxxxxxx, President

B & B Resources, Inc.

/s/ Xxxxx Xxxxxxx

Xxxxx Xxxxxxx, President

Xxxxx & Xxxxx, Inc.

/s/ Xxxxx Xxxxxxx

Xxxxx Xxxxxxx, President

XxXxxxx Xxxxxxx Construction Co

/s/ Xxxxx Xxxxxxx

Xxxxx Xxxxxxx, President

Xxxx Construction, Inc.

/s/ Xxxxx Xxxxxxx

Xxxxx Xxxxxxx, President

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