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                                                                   Exhibit 10-BG
                               THIRD AMENDMENT TO
                              EMPLOYMENT AGREEMENT

         This third amendment to the employment agreement entered into on the
15th day of March, 1995, by and between the Columbia Energy Group (formerly
named "The Columbia Gas System, Inc.") (the "Company") and Oliver G. Richard III
(the "Executive"), which agreement was amended on the 17th day of January, 1996,
and again on the 14th day of July, 1999 (the agreement, as amended, the
"Agreement"), is made effective the 21st day of July, 2000.

                                    RECITALS

         WHEREAS, the Company and the Executive are parties to the Agreement;
and

         WHEREAS, the Company has entered into an Agreement and Plan of Merger
among Columbia Energy Group, NiSource, Inc., New NiSource, Inc., Parent
Acquisition Corp., Company Acquisition Corp. and NiSource Finance Corp., dated
as of February 27, 2000, as amended and restated as of March 31, 2000 (the
"Merger Agreement"), shareholder approval of which would constitute a Change in
Control(1) for purposes of the Agreement; and

         WHEREAS, the Company desires to make arrangements at this time to help
further assure the Executive's continuing dedication to his duties to the
Company and its shareholders through the critical period ending with the
"Effective Time" as defined in the Merger Agreement; and

         WHEREAS, the Company and the Executive wish to amend certain provisions
in the Agreement to effect such objectives; and

         WHEREAS, Section 15(2) of the Agreement provides that the Agreement may
be amended by written instrument executed by the Company and the Executive.

         NOW, THEREFORE, for valuable consideration, the receipt and sufficiency
of which is acknowledged by the Company and the Executive, the Company and the
Executive hereby agree as follows:

         1. Section 8(e)(i) of the Agreement shall be amended to read as
follows:

                  "(e) (i) The 90th day after the Executive notifies the Company
                  (or any successor to the Company) in writing that he is
                  terminating his employment as a result of the occurrence of a
                  "Change in Control" (as that term is defined below), PROVIDED
                  such notice is given in

__________________

         1        Capitalized terms in this Amendment shall have the meaning as
                  set forth in the Agreement except as otherwise expressly set
                  forth herein.
         2        References to sections are to the sections in the Agreement,
                  as amended by the amendment dated July 14, 1999.
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                  writing by the Executive to the Company no later than 180 days
                  after such event; PROVIDED, further, that if the Executive
                  terminates his employment as a result of Company shareholder
                  approval of the Agreement and Plan of Merger among Columbia
                  Energy Group, NiSource, Inc., New NiSource, Inc., Parent
                  Acquisition Corp., Company Acquisition Corp. and NiSource
                  Finance Corp., dated as of February 27, 2000, as amended and
                  restated as of March 31, 2000 (the "Merger Agreement"), the
                  Executive may give written notice of such termination of
                  employment to the Company at any time during the period
                  beginning on the date of shareholder approval of the Merger
                  Agreement and ending on the "Effective Time" as defined in the
                  Merger Agreement (the "Effective Time"), and, in such case,
                  the Executive's employment shall terminate on the date
                  specified in such notice of termination, which termination
                  date shall (unless otherwise mutually agreed by Executive and
                  the Company) be at least 14 days after the date notice of
                  termination is given but not sooner than 90 days after
                  shareholder approval of the Merger Agreement (unless the
                  termination date specified in the notice of termination is the
                  Effective Time, in which case the termination date shall be
                  the Effective Time whether or not the Effective Time occurs
                  prior to expiration of such 14 and 90 day periods); PROVIDED,
                  further, that all payments to be made to the Executive under
                  Sections 9(d)(i), 9(d)(ii)(B) and 9(d)(ii)(C) (if under
                  Section 9(d)(ii)(C) the Company decides on or prior to the
                  date of employment termination to pay a cash equivalent
                  thereunder) and any other payments to be made under this
                  Agreement to the Executive upon termination of employment
                  because of a termination of employment pursuant to this
                  Section 8(e)(i) after Company shareholder approval of the
                  Merger Agreement, shall be paid by the Company to the
                  Executive on or before the earlier of (A) the 30th business
                  day following the termination of the Executive's employment or
                  (B) the "Closing Date" as defined in the Merger Agreement (the
                  "Closing Date"), and, furthermore, any payments under Section
                  9(f)(i) shall be paid to the Executive on the Closing Date."

         All provisions of the Agreement not specifically mentioned in this
Third Amendment shall be considered modified to the extent necessary to be
consistent with the changes made in this Third Amendment.

                                            Columbia Energy Group

                                            By /s/ Robert H. Beeby
                                               --------------------------------
                                               Chairman of the Compensation
                                               Committee

Attested:

/s/ Sharon B. Heaton                        /s/ Oliver G. Richard III
---------------------------------           -----------------------------------
                                            Oliver G. Richard III