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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                 SCHEDULE 14D-9

                SOLICITATION/RECOMMENDATION STATEMENT PURSUANT TO
             SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934
                               (AMENDMENT NO. 45)

                              COLUMBIA ENERGY GROUP
                            (NAME OF SUBJECT COMPANY)


                              COLUMBIA ENERGY GROUP
                      (NAME OF PERSON(S) FILING STATEMENT)

                          COMMON STOCK, PAR VALUE $0.01
                         (TITLE OF CLASS OF SECURITIES)

                                    197648108
                      (CUSIP NUMBER OF CLASS OF SECURITIES)

                              MICHAEL W. O'DONNELL
                SENIOR VICE PRESIDENT AND CHIEF FINANCIAL OFFICER
                              COLUMBIA ENERGY GROUP
                            13880 DULLES CORNER LANE
                             HERNDON, VIRGINIA 20171
                                 (703) 561-6000
           (NAME, ADDRESS AND TELEPHONE NUMBER OF PERSON AUTHORIZED TO
               RECEIVE NOTICE AND COMMUNICATIONS ON BEHALF OF THE
                           PERSON(S) FILING STATEMENT)

                                    COPY TO:

                             NEIL T. ANDERSON, ESQ.
                               SULLIVAN & CROMWELL
                                125 BROAD STREET
                            NEW YORK, NEW YORK 10004
                                 (212) 558-4000


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         This    Amendment    No.    45    amends    and     supplements     the
Solicitation/Recommendation   Statement   on  Schedule   14D-9  filed  with  the
Securities and Exchange Commission on July 6, 1999, and as subsequently  amended
July 6, 1999,  July 9, 1999,  July 12, 1999,  July 15, 1999, July 16, 1999, July
20, 1999, July 22, 1999, July 30, 1999,  August 3, 1999,  August 4, 1999, August
5, 1999,  August 6, 1999,  August 9, 1999,  August 11,  1999,  August 12,  1999,
August 13, 1999,  August 16, 1999,  August 17, 1999, August 19, 1999, August 31,
1999,  September  2, 1999,  September 3, 1999,  September 7, 1999,  September 9,
1999,  September 10, 1999, September 13, 1999, September 14, 1999, September 15,
1999,  September 16, 1999, September 17, 1999, September 20, 1999, September 21,
1999,  September 22, 1999, September 23, 1999, September 24, 1999, September 27,
1999,  September 28, 1999,  September 29, 1999,  September 30, 1999,  October 1,
1999, October 4, 1999,  October 5, 1999 and October 6, 1999 (as so amended,  the
"Schedule  14D-9"),  by  Columbia  Energy  Group,  a Delaware  corporation  (the
"Company"),   relating  to  the  tender  offer  by  NiSource  Inc.,  an  Indiana
corporation,  to purchase  for cash  through its  wholly-owned  subsidiary,  CEG
Acquisition Corp., a Delaware corporation, all of the outstanding common shares,
par value $0.01 per share, of the Company (the "Offer").  Capitalized terms used
but not defined herein have the meaning ascribed to them in the Schedule 14D-9.

ITEM 6.  RECENT TRANSACTIONS AND INTENT WITH RESPECT TO SECURITIES.

         Item 6 is hereby supplemented and amended by adding the following:

         On October 6, 1999,  pursuant to its  previously  announced  repurchase
program,  the Company  purchased  10,600 Shares on the open market at a weighted
average price per share of $57.0377.












                                   SIGNATURE

         After reasonable  inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.



                           COLUMBIA ENERGY GROUP



                                 /s/ Michael W. O'Donnell
                           By:----------------------------------------------
                           Name: Michael W. O'Donnell
                           Title:  Senior Vice President and Chief Financial
                           Officer


Dated: October 7, 1999