Exhibit 99.A

April 18, 2006

Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Commissioners:

We have read the statements made by ANR Pipeline Company (copy attached), which we understand will be filed with the Securities and Exchange Commission, pursuant to Item 4.01 of Form 8-K, as part of the Form 8-K of ANR Pipeline Company dated April 12, 2006. We agree with the statements concerning our Firm in such Form 8-K.

Very truly yours,

/s/ PricewaterhouseCoopers LLP

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