EXHIBIT 10-B
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                                                      ACE WHOLLY OWNED AGREEMENT


                               SECOND AMENDMENT
                                    TO THE
                          PURCHASE AND SALE AGREEMENT
                                BY AND BETWEEN
                        ATLANTIC CITY ELECTRIC COMPANY
                                      AND
                               NRG ENERGY, INC.


          SECOND AMENDMENT TO THE PURCHASE AND SALE AGREEMENT (the "Second
Amendment") by and between Atlantic City Electric Company, a New Jersey
corporation ("ACE" or "Seller"), and NRG Energy, Inc., a Delaware corporation
("Buyer"), dated as of October 31, 2001.  Seller and Buyer may each be referred
to herein individually as a "Party" and collectively as the "Parties."
Capitalized terms used and not otherwise defined in this Second Amendment shall
have the respective meanings assigned to them in the Amended Agreement (as
defined below).

          WHEREAS, Seller and Buyer are Parties to the Purchase and Sale
Agreement, dated as of January 18, 2000 (the "Agreement"), and the Amendment to
the Agreement, dated as of June 22, 2001 (the "First Amendment" and, together
with the Agreement, the "Amended Agreement"), providing for the sale and
assignment by Seller of the Purchased Assets and the Assumed Liabilities and the
purchase and assumption by Buyer of the Purchased Assets and the Assumed
Liabilities, upon the terms and conditions set forth in the Amended Agreement;
and

          WHEREAS, the Closing of the transactions contemplated by the Amended
Agreement and the ACE Related Purchase Agreement, as amended, has been
unexpectedly delayed; and

          WHEREAS, as a result of the delay of the Closing, the Parties desire
to further amend the Amended Agreement as set forth herein and the ACE Related
Purchase Agreement, as amended, as set forth in the amendment thereto, which is
being entered into simultaneously with this Second Amendment, to, among other


things, extend the termination date of the Amended Agreement and the ACE Related
Purchase Agreement, as amended.

          NOW THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, Seller and Buyer hereby agree as
follows:


                                   ARTICLE I

           Amendment of Certain Provisions of the Amended Agreement
           --------------------------------------------------------

          Section 1.1  Certain Definitions.  Section 1.1 of the Agreement is
                       -------------------
hereby amended to include the following additional provision:

     "(165) "Special Access Agreement" means the easement and license agreement
             -------------------------
     between Buyer and Seller, or any Affiliate thereof, to be delivered at the
     Closing, pursuant to which Buyer will provide Seller, or an Affiliate
     thereof, with rights with respect to certain Excluded Assets, comprised of
     microwave antennae, transmission lines and associated equipment located at
     the B.L. England Station, relating to the transmission and delivery of
     electric power or the operation of B.L. England Station."

            Section 1.2  Deliveries by Seller.  Section 3.6(f) is hereby
                         --------------------
amended and restated in its entirety to read as follows:

     "(f)  The Access Agreement and the Special Access Agreement, in each case,
     duly executed by Seller, or an Affiliate thereof, and in recordable form;"

           Section 1.3  Deliveries by Buyer.  Section 3.7(e) is hereby
                        -------------------
amended and restated in its entirety to read as follows:

     "(e)  The Access Agreement and the Special Access Agreement, in each case,
     duly executed by Buyer and in recordable form;"

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          Section 1.4  Certain Representations and Warranties of Seller.
                       -------------------------------------------------
Section 4.2 of the Agreement is hereby amended and restated in its entirety to
read as follows:

          "Seller has full corporate power and authority to execute and
     deliver this Agreement and each Additional Agreement to which it is a party
     and to consummate the transactions contemplated hereby and thereby.  Except
     for the approval of the respective provisos to clauses (iii) and (iv) of
     Section 9.1(b) hereof by the Board of Directors of Seller, the execution
     and delivery by Seller of this Agreement and each Additional Agreement to
     which it is a party and the consummation by Seller of the transactions
     contemplated hereby and thereby have been duly and validly authorized by
     all necessary corporate action required on the part of Seller.  This
     Agreement has been duly and validly executed and delivered by Seller and,
     subject to the receipt of Seller's Required Regulatory Approvals, this
     Agreement constitutes, and upon the execution and delivery by Seller of
     each Additional Agreement to which it is a party, each such Additional
     Agreement will constitute, the legal, valid and binding obligation of
     Seller, enforceable against Seller in accordance with its terms, except
     that such enforceability may be limited by applicable bankruptcy,
     insolvency, reorganization, fraudulent conveyance, moratorium or other
     similar Laws affecting or relating to enforcement of creditors' rights
     generally and general principles of equity (regardless of whether
     enforcement is considered in a proceeding at law or in equity)."

          Section 1.5  Certain Covenants of the Parties.
                       --------------------------------

                   (a) Section 6.5 of the Agreement is hereby amended to
include the following additional provisions:

          "(e)  Without limiting the generality of Section 6.5(b) of the
     Agreement, from and after the date of this Second Amendment, Seller and
     Buyer shall reasonably cooperate with each other to supplement the
     testimony provided to the NJBPU prior to the date hereof."

          "(f)  Seller and Buyer shall use their respective Commercially
     Reasonable Efforts to promptly enter into a Joint Defense Agreement
     relating to B.L. England Station, in form and substance satisfactory to
     each of Seller and Buyer.  Notwithstanding any provision of such Joint
     Defense Agreement to the contrary, the provisions of this Agreement shall
     govern and control any

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     conflict or inconsistency between or among the provisions hereof and the
     provisions of such Joint Defense Agreement."

                (b) Article VI of the Agreement is hereby amended to include
the following additional provision:

     "Section 6.18 Special Access Agreement. Without limiting the generality of
                   -------------------------
     Section 6.4(a), Buyer and Seller shall prepare, negotiate and enter into,
     or cause to be entered into, the Special Access Agreement, in form and
     substance satisfactory to each of Buyer and Seller, on or prior to the
     Closing Date."

          Section 1.6  Certain Termination Provisions.  Section 9.1(b) of the
                       ------------------------------
Agreement, as amended by Section 1.9 of the First Amendment, is hereby amended
and restated in its entirety to read as follows:

          "This Agreement may be terminated by Seller, on the one hand, or
     Buyer, on the other hand, upon written notice to the other Party, (i) at
     any time prior to the Closing if any court of competent jurisdiction shall
     have issued an order, judgment or decree permanently restraining, enjoining
     or otherwise prohibiting the Closing, and such order, judgment or decree
     shall have become final and nonappealable; (ii) at any time prior to the
     Closing if any Law shall have been enacted or issued by any Governmental
     Authority which, directly or indirectly, prohibits the consummation of the
     transactions contemplated by this Agreement or by any Additional Agreement;
     (iii) solely with respect to the Deepwater Station Transactions, at any
     time after December 31, 2001, if the Closing of the Deepwater Station
     Transactions shall not have occurred on or before such date, provided,
     however, that neither Seller nor Buyer shall be permitted to so terminate
     this Agreement, solely with respect to the Deepwater Station Transactions,
     at any time prior to March 1, 2002, if the Board of Directors of Seller
     shall have approved this proviso to this clause (iii) on or prior to
     December 31, 2001; or (iv) solely with respect to the B.L. England Station
     Transactions, at any time after December 31, 2001, if the Closing of the
     B.L. England Station Transactions shall not have occurred on or before such
     date, provided, however, that neither Seller nor Buyer shall be permitted
     to so terminate this Agreement, solely with respect to the B.L. England
     Station Transactions, at any time prior to March 1, 2002, if the Board of
     Directors of Seller shall have approved this proviso to this clause (iv) on
     or prior to December 31, 2001; and, provided,

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     further, that the right to terminate this Agreement under Section
     9.1(b)(iii) or Section 9.1(b)(iv) shall not be available to any Party whose
     breach of this Agreement has caused, or resulted in, the failure of the
     Closing to occur on or before such applicable date."


                                  ARTICLE II

                   Release, Waiver and Additional Provisions
                   -----------------------------------------

               Section 2.1  Release and Waiver of Claims Against Seller Parties.
                            ----------------------------------------------------

                       (a) Buyer and each of its Affiliates hereby
unconditionally and irrevocably releases, acquits and forever discharges Seller
and its Affiliates, shareholders, officers, directors, employees, agents,
representatives, successors and assigns (collectively, the "Seller Parties"),
                                                            --------------
effective as of the date hereof, of and from, and hereby unconditionally and
irrevocably waives, any and all claims, demands, debts, losses, costs, expenses,
proceedings, judgments, damages, actions, causes of action, suits, contracts,
agreements, obligations, accounts and liabilities of any kind or character
whatsoever, known or unknown, suspected or unsuspected, in contract or in tort,
at law or in equity ("Claims"), that the Buyer or any of its Affiliates alone or
with any other Person had, now has, or might hereafter have against the Seller
Parties or any of them jointly and/or severally, for or by reason of any matter,
circumstance, event, action, omission, cause or thing whatsoever occurring or
existing on or before the date of this Second Amendment, arising under, relating
to or in connection with the Amended Agreement (or any of the Exhibits or
Schedules thereto) and which are set forth in Schedule 2.1 to this Second
                                              ------------
Amendment.

                       (b) Buyer hereby represents and warrants to Seller that,
as of the date of this Second Amendment, to Buyer's knowledge, Buyer does not
have any Claims against any Seller Party, other than as set forth in Schedule
                                                                     --------
2.1 to this Second Amendment, which Claims have been released and waived
pursuant to Section 2.1(a).

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          Section 2.2  Release and Waiver of Claims Against Buyer Parties.
                       --------------------------------------------------

               (a)     Seller and each of its Affiliates hereby unconditionally
and irrevocably releases, acquits and forever discharges Buyer and its
Affiliates, shareholders, officers, directors, employees, agents,
representatives, successors and assigns (collectively, the "Buyer Parties"),
effective as of the date hereof, of and from, and hereby unconditionally and
irrevocably waives, any and all Claims, that the Seller or any of its Affiliates
alone or with any other Person had, now has, or might hereafter have against the
Buyer Parties or any of them jointly and/or severally, for or by reason of any
matter, circumstance, event, action, omission, cause or thing whatsoever
occurring or existing on or before the date of this Second Amendment, arising
under, relating to or in connection with the Amended Agreement (or any of the
Exhibits or Schedules thereto) and which are set forth in Schedule 2.2 to this
                                                          --------
Second Amendment.

               (b)     Seller hereby represents and warrants to Buyer that, as
of the date of this Second Amendment, to Seller's knowledge, Seller does not
have any Claims against any Buyer Party, other than as set forth in Schedule 2.2
                                                                    --------
to this Second Amendment, which Claims have been released and waived pursuant to
Section 2.2(a).

          Section 2.3  Disclosed Matters.  Pursuant to Section 6.7 of the
                       -----------------
Agreement, Buyer and Seller hereby acknowledge and agree that the supplemental
or amended disclosure set forth in the Schedules to the Amended Agreement being
delivered by Seller to Buyer contemporaneously with this Second Amendment and
dated as of the date hereof shall, for purposes of the Amended Agreement, as
further  amended hereby, including for purposes of determining whether the
conditions to Closing set forth in Article VII of the Agreement are satisfied,
be deemed to have been disclosed as of January 18, 2000.

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                                  ARTICLE III

                           Miscellaneous Provisions
                           ------------------------

          Section 3.1  Amendment and Modification.  Subject to applicable Law,
                       --------------------------
this Second Amendment may be amended, supplemented or otherwise modified only by
written agreement entered into by all Parties.

          Section 3.2  Waiver of Compliance; Consents.  To the extent
                       ------------------------------
permitted by applicable Law, any failure of any of the Parties to comply with
any covenant, agreement or condition set forth herein may be waived by the Party
entitled to the benefit thereof only by a written instrument signed by such
Party, but any such waiver shall not operate as a waiver of, or estoppel with
respect to, any prior or subsequent failure to comply therewith.

          Section 3.3  Notices.  All notices and other communications hereunder
                       -------
shall be in writing and shall be given in accordance with Section 10.8 of the
Agreement.

          Section 3.4  Assignment.  This Second Amendment shall be binding upon
                       ----------
and inure to the benefit of the Parties and their respective successors and
permitted assigns, but neither this Second Amendment nor any of the rights,
interests, obligations or remedies hereunder shall be assigned by any Party
hereto, including by operation of law, without the prior written consent of the
other Parties, nor is this Second Amendment intended to confer upon any other
Person any rights, interests, obligations or remedies hereunder.  Without
limiting the generality of the foregoing, no provision of this Second Amendment
shall create any third-party beneficiary rights in any Employee or former
employee of Seller (including any beneficiary or dependent thereof) in respect
of continued employment or resumed employment, and no provision of this Second
Amendment shall create any rights in any such Persons in respect of any benefits
that may be provided, directly or indirectly, under any employee benefit plan or
arrangement except  as expressly provided for thereunder.  Notwithstanding the
foregoing, (i) Seller may assign all or any portion of its rights, interests,
obligations and remedies hereunder to Conectiv, a Delaware corporation, or any
of Conectiv's wholly owned subsidiaries; provided, however, that no such
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assignment shall (A) materially impair or delay the consummation of the
transactions contemplated hereby or by the Amended Agreement or (B) relieve or
discharge Seller from any of its obligations hereunder or under the Amended
Agreement; and (ii) Buyer may assign all or any portion of its

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