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                                                                      EXHIBIT 5



              LETTERHEAD OF LEBOEUF, LAMB, GREENE & MACRAE, L.L.P.


                                             September 30, 1997

Bay State Gas Company
300 Friberg Parkway
Westborough, MA 01581-5039


Ladies and Gentlemen:

       We have acted as counsel to Bay State Gas Company, a Massachusetts
corporation (the "Company"), in connection with its Registration Statement on
Form S-8 (the "Registration Statement") executed and filed for the purpose of
registering under the Securities Act of 1933, as amended (the "1933 Act"),
500,000 shares of the Company's Common Stock, $3.33 1/3 par value (the "Common
Stock"), to be sold pursuant to the Company's Stock Performance Sharing Plan
(the "Plan") (formerly, the Bay State Gas Company Key Employee Long-Term
Incentive Plan).

       In connection with this opinion, we have examined originals or copies,
certified or otherwise identified to our satisfaction, of such instruments,
certificates, records and documents, and have reviewed such questions of law, as
we have deemed necessary or appropriate for purposes of this opinion. In such
examination, we have assumed the genuineness of all signatures, the authenticity
of all documents submitted to us as originals, the conformity to the original
documents of all documents submitted to us as copies and the authenticity of the
originals of all such latter documents. As to any facts material to this
opinion, we have relied upon the aforesaid instruments, certificates, records
and documents and inquiries of Company representatives.

       Based upon the foregoing examination, and subject to the limitations set
forth below, we are of the opinion that the Common Stock, when sold pursuant to
the Plan, will be validly issued, fully paid and nonassessable when:

       (a)    the Registration Statement shall have become and so long as it
shall remain effective for the purpose of the issue and sale of the Common
Stock; and

       (b)    the certificates for the Common Stock have been duly executed,
countersigned, registered and delivered in accordance with the provisions of the
Plan and the consideration therefor provided for in the Plan has been received
by the Company.







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Bay State Gas Company
September 30, 1997
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       This opinion is rendered under and limited to the law of The Commonwealth
of Massachusets (without reference to "blue sky" matters) and the federal law of
the United States. We consent to the filing of this opinion as Exhibit 5 to the
Registration Statement and the use of our name therein, and in any amendments
thereto.

                                        Very truly yours,

                                        LEBOEUF, LAMB, GREENE & MACRAE, L.L.P.