Exhibit 5.1

June 1, 2011

Alpha Natural Resources, Inc.

Guarantors listed on Schedule I hereto

c/o Alpha Natural Resources, Inc.

One Alpha Place

P.O. Box 2345

Abingdon, Virginia 24212

Ladies and Gentlemen:

We have acted as special counsel to Alpha Natural Resources, Inc., a Delaware corporation (the “Company”), in connection with its offering pursuant to a registration statement on Form S-3 (No. 333-165473) (the “Registration Statement”) and the prospectus dated March 15, 2010, as supplemented by the prospectus supplement dated May 18, 2011 (together, the “Prospectus”), of $800,000,000 aggregate principal amount of its 6% Senior Notes due 2019 and $700,000,000 aggregate principal amount of its 6.25% Senior Notes due 2021 (together, the “Securities”). The Securities were issued under an indenture dated as of June 1, 2011 (the “Base Indenture”), among the Company, the Company’s subsidiaries listed on Schedule I hereto, as guarantors (the “Guarantors”), and Union Bank, N.A., as trustee (the “Trustee”), as amended by the first supplemental indenture, dated as of June 1, 2011 (the “First Supplemental Indenture” and, together with the Base Indenture, the “Indenture”), among the Company, the Guarantors and the Trustee. The Indenture includes the guarantees of the Securities by the Guarantors (the “Guarantees”).

In arriving at the opinions expressed below, we have reviewed the following documents:

Alpha Natural Resources, Inc. et al., p. 2

In addition, we have reviewed the originals or copies certified or otherwise identified to our satisfaction of all such corporate records of the Company and such other documents, and we have made such investigations of law, as we have deemed appropriate as a basis for the opinions expressed below.

In rendering the opinions expressed below, we have assumed the authenticity of all documents submitted to us as originals and the conformity to the originals of all documents submitted to us as copies. In addition, we have assumed and have not verified the accuracy as to factual matters of each document we have reviewed.

Based on the foregoing, and subject to the further assumptions and qualifications set forth below, it is our opinion that:

1. The Securities have been validly issued by the Company and are the valid, binding and enforceable obligations of the Company, entitled to the benefits of the Indenture.

2. The Guarantees are the valid, binding and enforceable obligations of the applicable Guarantor, entitled to the benefits of the Indenture.

Insofar as the foregoing opinions relate to the validity, binding effect or enforceability of any agreement or obligation of the Company or any Guarantor, (a) we have assumed that the Company or such Guarantor and each other party to such agreement or obligation has satisfied those legal requirements that are applicable to it to the extent necessary to make such agreement or obligation enforceable against it (except that no such assumption is made as to the Company regarding matters of the federal law of the United States of America, the law of the State of New York or the General Corporation Law of the State of Delaware that in our experience normally would be applicable to general business entities with respect to such agreement or obligation) and (b) such opinions are subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and to general principles of equity.

The foregoing opinions are limited to the federal law of the United States of America, the law of the State of New York and the General Corporation Law of the State of Delaware (including the applicable provisions of the Delaware Constitution and reported judicial decisions interpreting the General Corporation Law of the State of Delaware).

Alpha Natural Resources, Inc. et al., p. 3

We hereby consent to the use of our name in the Prospectus under the heading “Legal Matters,” as counsel for the Company that has passed on the validity of the Securities and to the filing of this opinion as Exhibit 5.1 to the Company’s Current Report on Form 8-K dated June 1, 2011. In giving such consent, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended, or the rules and regulations of the Securities and Exchange Commission thereunder. The opinions expressed herein are rendered on and as of the date hereof, and we assume no obligation to advise you or any other person, or to make any investigations, as to any legal developments or factual matters arising subsequent to the date hereof that might affect the opinions expressed herein.

Schedule I

I-1

I-2