Enbridge Pipelines Inc. 3000, 425-1st Street SW Calgary, AB T2P 3L8

Exhibit 10.4

Enbridge Pipelines Inc. 0000, 000-0^xx Xxxxxx XX Xxxxxxx, XX X0X 0X0

Enbridge Energy Limited Partnership

0000 Xxxxxxxxx Xxxxxx, Xxxxx 0000

Xxxxxxx, XX 00000

March 13, 2015

United Refining Company and

Kiantone Pipeline Corporation

000 00^xx Xxx.

Xxx Xxxx, Xxx Xxxx 00000

Attention: X. Xxxxxx Happy

Subject: Amendment to the Letter Agreement between Enbridge Pipelines Inc., Enbridge Energy Limited Partnership, United Refining Company and Kiantone Pipeline Corporation dated July 31, 2014 (the “Letter Agreement”)

The parties agree that Section C.1 of the Letter Agreement shall be amended by replacing “March 13, 2015” with “March 27, 2015.”

Please acknowledge your agreement to the terms and conditions contained herein by signing the enclosed duplicate copy in the space provided below and returning the acknowledged copy to the undersigned.

ENBRIDGE ENERGY, LIMITED PARTNERSHIP BY ENBRIDGE PIPELINES (LAKEHEAD) L.L.C. ITS GENERAL PARTNER						ENBRIDGE PIPELINES INC.
Per:		/s/ Xxxxx Xxxxxxx				Per:		/s/ X.X. Xxxxxxxx
		Xxxxx Xxxxxxx Vice President – U.S. Law						X.X. Xxxxxxxx V.P., Liquid Pipelines Law & Deputy General Counsel

UNITED REFINING COMPANY						KIANTONE PIPELINE CORPORATION
Per:		/s/ Xxxx X. Xxxxxxxxxxxx				Per:		/s/ Xxxx X. Xxxxxxxxxxxx
		Xxxx X. Xxxxxxxxxxxx Chairman & CEO						Xxxx X. Xxxxxxxxxxxx Chairman & CEO