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                                                                   EXHIBIT 10.36

                         MORTGAGE AND SECURITY AGREEMENT

                                 by and between

                           GREAT BAY POWER CORPORATION
                             222 International Drive
                              Portsmouth, NH 03801

                                       and

                               SELECT ENERGY, INC.
                                107 Selden Street
                                Berlin, CT 06037

                          Dated as of February 6, 2001


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                         MORTGAGE AND SECURITY AGREEMENT


         This MORTGAGE AND SECURITY AGREEMENT (this "Mortgage") is entered into
as of February 6, 2001, by and between GREAT BAY POWER CORPORATION, a New
Hampshire corporation with a mailing address of 222 International Drive,
Portsmouth, New Hampshire 03801, ("GBP") and Select Energy, Inc., a Connecticut
corporation with a mailing address of 107 Selden Street, Berlin, Connecticut
06037 ("Select Energy"), pursuant to a Purchase Power Agreement dated as of
February 6, 2001 (the "Purchase Agreement"), by and between GBP and Select
Energy.

         WHEREAS, GBP is the owner of an undivided 12.13240% interest in the
Seabrook Nuclear Power Plant located in Seabrook, New Hampshire ("Seabrook") and
has a percentage interest in the capacity and net electrical output of Seabrook
pursuant to an Agreement of Joint Ownership, Construction and Operation of
Nuclear Units dated May 1, 1973, as amended (the "JOA"); and

         WHEREAS, Select Energy is entitled to sell electrical power generated
by the Millstone Point Nuclear Power Plant Unit Nos. 2 and 3 located in
Connecticut ("Millstone"); and

         WHEREAS, the Purchase Agreement, providing for the purchase of
electrical power by the parties from each other, calls for Select Energy to
purchase from GBP fifty (50) megawatts ("MW") of electrical power from Seabrook
(representing approximately 4.3178% of the 1,158 MW maximum claimed capacity of
Seabrook) (the "Seabrook Power"), which capacity and associated energy GBP has
the right to sell pursuant to the JOA, on the terms and conditions set forth in
the Purchase Agreement; and

         WHEREAS, the Purchase Agreement also provides for the purchase by GBP
from Select Energy of a like amount of electrical power from Millstone (50 MW)
(the "Millstone Power"), which capacity and associated energy Select Energy has
the right to sell, on the terms and conditions set forth in the Purchase
Agreement; and

         WHEREAS, the Purchase Agreement also provides that delivery of
electrical power by the parties to each other shall occur contemporaneously and
that GBP shall pay for its energy from Select Energy on or subsequent to
delivery thereof, but that Select Energy shall pay for a portion of the Seabrook
Power prior to delivery of such power by GBP to Select Energy (the "Prepaid
Seabrook Power"); and

         WHEREAS, the Purchase Agreement further provides that GBP shall grant
to Select Energy a mortgage lien and security interest in all of GBP's
properties and assets at Seabrook to secure the obligations of GBP under the
Purchase Agreement (i) to deliver the Prepaid Seabrook Power and/or to make
payment in lieu thereof, and (ii) to make payment for the Millstone Power, to
the extent provided, and as more particularly described in, the Purchase
Agreement.

         NOW, THEREFORE, GBP by this Mortgage, in order to secure the
obligations hereinafter described, does hereby GRANT, BARGAIN, SELL, CONVEY,
WARRANT,


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ASSIGN, TRANSFER, MORTGAGE, PLEDGE, SET OVER AND CONFIRM unto Select Energy for
the benefit of Select Energy, and does hereby CREATE, A SECURITY INTEREST IN
FAVOR OF Select Energy for the benefit of Select Energy, in all of GBP's right,
title and interest in and to all of the assets, properties and rights of GBP
referred to in the following Granting Clauses, whether now owned or hereafter
acquired (the "Mortgaged Property"):

                              GRANTING CLAUSE FIRST

                                      LAND

         The fee simple estate owned by GBP located in the Town of Seabrook,
County of Rockingham and State of New Hampshire more particularly described in
SCHEDULE 1 hereto (the "Land").

                             GRANTING CLAUSE SECOND

                                  IMPROVEMENTS

         All buildings, structures, fixtures and other improvements and
replacements thereof and additions thereto now or hereafter located on the Land,
and all fixtures, attachments and equipment of every nature whatsoever now or
hereafter owned by GBP and located in or on, or attached to, and used or
intended to be used in connection with the operation of the business on the Land
(the "Improvements") (together with the Land, the "Real Property").

                              GRANTING CLAUSE THIRD

                           EASEMENTS AND RIGHTS OF WAY

         All of GBP's right, title and interest in and to all streets, roads,
public places, easements and rights-of-way, existing or hereafter arising,
public or private, adjacent to and used in connection with, belonging or
pertaining to the Real Property and all uses, servitudes, licenses, tenements,
hereditaments and appurtenances now or hereafter belonging or appertaining to
any of the foregoing (collectively, "Easements and Rights of Way").

                             GRANTING CLAUSE FOURTH

                                 OTHER PROPERTY

         All of GBP's right, title and interest in all rights, hereditaments and
appurtenances pertaining to any of the foregoing, and all properties, rights or
interests of every kind or character that GBP now has or at any time hereafter
acquires in and to the Real Property, or the Improvements, including without
limitation, water rights, rights of ingress and egress and all reversionary
rights and interests of GBP with respect to such property.

                              GRANTING CLAUSE FIFTH



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                                PERSONAL PROPERTY

         All properties, assets and rights of GBP constituting tangible personal
property under applicable law, now owned or hereafter acquired or arising,
located at the Real Property, and used in connection with the Real Property (the
"Personal Property"), including without limiting the generality of the
foregoing, (i) all machinery, equipment, fixtures, furnishings and inventory,
now or hereafter attached to or used in or about the Real Property or the
Improvements or that are necessary or useful for the use and occupancy of the
Improvements for the purposes for which they were or are to be attached, placed,
erected, constructed or developed, or which Personal Property is or may be used
in or is related to the planning, development, financing or operation of the
Improvements, and all renewals of or replacements or substitutions for any of
the foregoing, whether or not the same are or shall be attached to the Real
Property or the Improvements; (ii) all building materials and equipment now or
hereafter delivered to and intended to be installed in or on the Real Property
or the Improvements; (iii) all plans and specifications for the Improvements;
(iv) all contracts relating to the Real Property, the Improvements or the
Personal Property; and (v) all permits, licenses, franchises, certificates, and
other rights and privileges obtained in connection with the Real Property, the
Improvements or the Personal Property, to the full extent GBP has the legal
right and authority to grant a security interest therein.

                              GRANTING CLAUSE SIXTH

                                    PROCEEDS

         All reversions, remainders, rents, issues, profits, revenues and other
income and products, proceeds and replacements of, and accessions and additions
to, any of the foregoing property, all proceeds of the conversion, voluntary or
involuntary, of any of the foregoing property into cash or liquidated claims,
including, without limitation, all proceeds of sales, leases or other
dispositions, judgments, insurance claims, damage awards, condemnation
proceedings or the taking, damage or destruction to any of the foregoing, and
all right, title and interest of every kind and nature whatsoever of GBP in and
to the same and every part thereof; provided, however, that nothing in this
Granting Clause Sixth shall preclude GBP from deriving and retaining income and
profits from the Real Property, Easements and Rights of Way, other property and
Personal Property prior to the occurrence of any Mortgage Default.

                             GRANTING CLAUSE SEVENTH

                    12.13240% OWNERSHIP INTEREST IN SEABROOK

         All of GBP's 12.13240% undivided ownership interest in common with
other Participants (as defined in the JOA) in Seabrook, the Land being located
in the Town of Seabrook, Rockingham County, New Hampshire and the Easements and
Rights of Way being located in the Towns of Seabrook, Hampton Falls and Hampton,
Rockingham County, New Hampshire.



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         TO HAVE AND TO HOLD the Mortgaged Property unto Select Energy and its
successors and permitted assigns forever (subject to Section 8.2 hereof).


                                   ARTICLE I

                                   DEFINITIONS

         1.1      TERMS DEFINED. Except as otherwise expressly provided, all
capitalized terms used in this Mortgage, the exhibits hereto and any
certificates, reports or other documents or instruments made or delivered
pursuant to or in connection with this Mortgage shall have the meanings set
forth for such terms in EXHIBIT A hereto or as otherwise defined herein;
capitalized terms not so defined shall have the meanings given such terms in the
Purchase Agreement.

                                   ARTICLE II

                             THE SECURED OBLIGATIONS

         2.1      THE SECURED OBLIGATIONS. This Mortgage is given to secure the
following:

                  (a)      THE PURCHASE AGREEMENT. The rights of Select Energy
         to delivery of the Prepaid Seabrook Power and/or cash payments in lieu
         thereof, together with certain related amounts, and to payment for the
         Millstone Power (subject to limitation as herein provided), in
         accordance with Sections 7.2, 7.3 and 7.5 of the Purchase Agreement.

                  (b)      SECURITY DOCUMENTS. The obligations of GBP to pay any
         amounts due to Select Energy under this Mortgage and to perform any
         obligation of GBP under this Mortgage.

The obligations described in this Section 2.1 are hereinafter collectively
called the "Secured Obligations." NOTICE IS HEREBY GIVEN pursuant to New
Hampshire RSA 479:3 that this Mortgage secures the Secured Obligations up to a
maximum amount of ten million dollars ($10,000,000).

         2.2      FULLY SECURED. Each and all Secured Obligations at any time
outstanding shall in all respects be fully secured hereby, without preference,
priority or distinction on account of date or dates or the actual time or times
of the issue or maturity of said Secured Obligations or any of them, so that all
Secured Obligations at any time issued and outstanding shall have the same
right, lien and preference under and by virtue of this Mortgage and shall all be
fully secured hereby, with like effect as if they had all been executed and
delivered simultaneously on the date hereof whether such Secured Obligations, or
any of them, shall actually be issued on such date or some future date, or
whether such Secured Obligations, or any of them, shall have been authorized to
be issued on the date hereof or in the future under the provisions of this
Mortgage or the Purchase Agreement, or of any document or instrument created in
furtherance of the purposes of this Mortgage.



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         2.3      PRIOR MORTGAGES. The parties acknowledge that the mortgage
liens and security interests granted by GBP to UNITIL Power Corp., a New
Hampshire corporation ("UNITIL"), as set forth in that certain Second Mortgage
and Security Agreement by and between GBP and UNITIL and that certain Third
Mortgage and Security Agreement by and between GBP and UNITIL, both dated as of
December 22, 1993, and recorded, respectively, at the Rockingham County (N.H.)
Registry of Deeds at Book 3041, Page 809, and Book 3041, Page 837 (collectively,
the "Senior Liens"), are prior in right and time to this Mortgage.

                                   ARTICLE III

                               SECURITY AGREEMENT

         3.1      SECURITY INTEREST. This Mortgage shall be a security agreement
between GBP, as the debtor, and Select Energy, as the secured party, for the
benefit of Select Energy with respect to those portions of the Mortgaged
Property constituting personal property or fixtures governed by the New
Hampshire Uniform Commercial Code (hereinafter called the "Code"), and GBP
grants to Select Energy for the benefit of Select Energy a security interest in
such portions of the Mortgaged Property. In addition to Select Energy's other
rights hereunder, Select Energy shall have all rights of a secured party under
the Code. GBP shall execute and deliver to Select Energy all financing
statements and continuation statements that may be reasonably requested by
Select Energy to establish and maintain the validity and priority of Select
Energy's security interest, and GBP shall bear all costs thereof, in accordance
with the Purchase Agreement. If Select Energy should dispose of any of the
Mortgaged Property pursuant to the Code, ten (10) days' written notice by Select
Energy to GBP shall be deemed to be reasonable notice.

         3.2      FIXTURES. Some of the items of the Mortgaged Property
described herein are goods that are or are to become fixtures related to the
Mortgaged Property, and it is intended that, as to those goods, this Mortgage
shall be effective as a financing statement filed as a fixture filing from the
date of its recording in the Registry of Deeds of Rockingham County.

                                   ARTICLE IV

                      REPRESENTATIONS AND COVENANTS OF GBP

         GBP makes the following representations and covenants, which shall
continue in full force and effect until the discharge in full of the Secured
Obligations, following which the provisions of this Article IV shall terminate
and be of no further force or effect:

         4.1      TITLE TO PROPERTY. GBP hereby represents and warrants that GBP
has not granted any liens on the Mortgaged Property other than the Senior Liens
and Permitted Encumbrances. GBP has all rights in and to the Mortgaged Property
owned by it necessary to permit the use of such properties as provided for in
the JOA. GBP shall and will warrant and defend the lien of this Mortgage against
all claims and demands of other lienholders, other than the holders of the
Senior Liens and Permitted Encumbrances, and shall and will maintain and
preserve the lien of this Mortgage as a valid mortgage lien on and a priority
security interest in the Mortgaged Property and every part thereof, subject only
to the Senior Liens and Permitted Encumbrances, so





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long as any of the Secured Obligations are outstanding or undischarged, and GBP
at its expense will take or cause to be taken such action as may be necessary to
discharge or eliminate or bond any Lien on the Mortgaged Property which is
superior to this Mortgage (other than the Senior Liens and Permitted
Encumbrances) as the same shall arise at any time.

         4.2      THE MORTGAGED PROPERTY. GBP hereby covenants and agrees that,
without the prior written approval of Select Energy, or as otherwise permitted
in the Purchase Agreement, GBP (i) other than in the ordinary course of business
and so long as any such transaction would not materially reduce or impair GBP's
interest in the Mortgaged Property, will not, directly or indirectly, convey,
assign, transfer, sell or otherwise dispose of all or any part of GBP's legal or
beneficial interest in the Mortgaged Property, and (ii) will not create or
permit to exist any Lien on its interest in the Mortgaged Property, which is
superior to, or pari passu with, this Mortgage, other than the Senior Liens and
Permitted Encumbrances.

         4.3      RECORDATION, PERFECTION, ETC.

                  (a)      GBP at its expense will at all times cause this
         Mortgage and any amendment or modification thereof or supplement
         thereto to be recorded, registered and filed and to be kept recorded,
         registered and filed and will cause any requisite financing statement
         with respect to this Mortgage to be filed, and will pay all such
         recording, registration, filing or other similar fees, taxes and
         charges, and will comply with all such statutes and regulations as may
         be required by law in order to establish, preserve and protect the
         mortgage lien and security interest of this Mortgage on the Mortgaged
         Property and the rights of Select Energy hereunder.

                  (b)      GBP represents and warrants that its chief executive
         office (as such term is used in Article 9 of the Code) is located at
         222 International Drive, Portsmouth, NH 03801, and that its chief place
         of business (as such term is used in Article 9 of the Code) is located
         at 222 International Drive, Portsmouth, NH 03801.

                  (c)      GBP will, at the request of Select Energy made from
         time to time, promptly furnish to Select Energy a copy of any mortgaged
         property list provided under the Senior Liens.

                  (d)      GBP will not (i) maintain its chief place of business
         or its chief executive offices at a location other than the location
         thereof (or change the mailing address of its chief executive office)
         referred to in Section 4.3(b) hereof, or (ii) change its name, in each
         case without having given Select Energy reasonable prior written notice
         and having delivered to Select Energy all additional agreements,
         financing statements, instruments or other documents which in the
         reasonable judgment of Select Energy are necessary to maintain recorded
         and perfected under applicable law the mortgage lien and the security
         interest created by this Mortgage.

                  (e)      GBP will promptly furnish Select Energy with an
         informational copy of any legal opinions delivered by or on behalf of
         GBP to the holders of the Senior Liens




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         pursuant to the provisions thereof, with respect to recordations,
         registrations, filings or other actions necessary to comply with the
         requirements of the Senior Liens.

         4.4      REPORTS OF ALTERATIONS. On or before March 1 of each calendar
year, GBP shall furnish or cause to be furnished to Select Energy a copy of any
report of alterations furnished to the holders of the Senior Liens or their
successors.

         4.5      NO CLAIMS AGAINST SELECT ENERGY. Nothing contained in this
Mortgage shall constitute any consent or request by Select Energy, express or
implied, for the performance of any labor or services or the furnishing of any
materials or other property in respect of the Mortgaged Property or any part
thereof, nor give GBP any right, power or authority to contract for or permit
the performance of any labor or services or the furnishing of any materials or
other property in such fashion as would permit the making of any claim against
Select Energy in respect thereof.

         4.6      LIENS; PERMITTED CONTESTS.

                  (a)      GBP will not directly or indirectly create, incur,
         assume or permit to exist, and will discharge, or promptly cause to be
         discharged, any Lien with respect to the Mortgaged Property or any part
         thereof (other than Liens voluntarily created by other owners of the
         Mortgaged Property under the JOA on their respective ownership
         interests) or its interest therein having priority over this Mortgage,
         other than the Senior Liens and Permitted Encumbrances.

                  (b)      GBP at its expense may contest by appropriate
         proceedings conducted in good faith the amount or validity or
         application, in whole or in part, of any Lien or any Legal Requirement,
         provided that (i) all proceedings to enforce the Lien against the
         Mortgaged Property or any part thereof shall have been duly suspended,
         (ii) in the case of a Legal Requirement, neither GBP nor Select Energy
         would be in any danger of any liability for failure to comply
         therewith, (iii) in the case of a judgment Lien, so long as the
         judgment it secures shall have been discharged or the execution thereof
         stayed pending appeal, in either case prior to the earlier of the
         commencement of proceedings for the enforcement thereof or 30 days
         after the entry thereof, and so long as such judgment shall have been
         discharged within 30 days after the expiration of any such stay, (iv)
         GBP shall have set aside on its books adequate reserves with respect
         thereto, or shall have established and shall maintain in effect
         adequate bonds or other security to protect against the enforcement of
         such Lien, and (v) the Debt of GBP relating to such Lien shall be paid
         before the period in which to redeem the portion of the Mortgaged
         Property affected thereby has expired.

         4.7      JOINT OWNERSHIP AGREEMENT. GBP hereby covenants and agrees
that it shall timely fulfill its obligations under the JOA, unless it cannot do
so as a result of a breach of the Purchase Agreement by Select Energy.




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         4.8      REPORTING REQUIREMENTS. GBP hereby covenants and agrees to
provide Select Energy with a detailed cash flow statement and forecast each
Monday during such time as this Mortgage is in effect.

                                   ARTICLE V

                                DEFAULT: REMEDIES

         5.1      DEFAULT. The following events shall each constitute a
"Mortgage Default" under this Mortgage:

                  (a)      The failure of GBP to deliver the Prepaid Seabrook
         Power, or to make payment in lieu thereof, in accordance with Sections
         7.2 and 7.3 of the Purchase Agreement;

                  (b)      The failure of GBP to pay for the Millstone Power
         within three (3) days of the date the same becomes due and payable as
         provided in the Master Power Purchase Agreement (defined below);

                  (c)      The filing by GBP of a voluntary petition under any
         section of the United States Bankruptcy Code, or the filing by one or
         more third parties of an involuntary petition against GBP under any
         section of the United States Bankruptcy Code, which involuntary
         petition is not dismissed within ninety (90) days of the date of
         filing;

                  (d)      The failure of GBP to comply with the covenants of
         this Mortgage within thirty (30) days of receipt by GBP of written
         notice of such noncompliance from Select Energy; and

                  (e)      The occurrence of an Event of Default under the
         Purchase Agreement.

         5.2      POWER OF ENFORCEMENT. If a Mortgage Default shall have
occurred and be continuing, Select Energy shall have the right--

                  (a)      except with respect to a Mortgage Default as defined
         in Section 5.1(e) hereof, to accelerate the entire remaining unpaid
         Prepaid Power Balance (as defined in the Purchase Agreement) together
         with all other amounts required to be paid in conjunction with the
         payment of such Prepaid Power Balance at such time, in accordance with
         Sections 7.2 and 7.3 of the Purchase Agreement; and

                  (b)      subject to Section 5.3 hereof, either with or without
         entry or taking possession as herein provided or otherwise, to proceed
         by suit or suits at law or in equity or by any other appropriate
         proceeding or remedy (i) to enforce the performance of the Secured
         Obligations, (ii) to foreclose the mortgage lien of this Mortgage and
         to cause to be sold as an entirety or in separate lots or parcels the
         Mortgaged Property, under the judgment or decree of a court or courts
         of competent jurisdiction or under the provisions of this Mortgage,
         (iii) to exercise any and all of the rights and remedies of a secured



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         creditor under the laws of the State of New Hampshire, (iv) to take
         possession of any or all of the Mortgaged Property, and (v) to pursue
         any other remedy available to it, as Select Energy shall deem most
         effectual for such purpose.

GBP agrees to reimburse Select Energy for all reasonable costs and expenses
incurred by Select Energy in pursuing any enforcement remedy authorized by this
Section 5.2 or otherwise authorized under the Purchase Agreement or this
Mortgage, including but not limited to reasonable attorneys' fees.

         5.3      POWER OF SALE; FORECLOSURE. This Mortgage is upon the
STATUTORY CONDITIONS and upon the further condition that all covenants and
agreements on the part of GBP herein undertaken shall be kept and fully and
timely performed. If a Mortgage Default shall have occurred and be continuing,
Select Energy shall have the right to foreclose pursuant to the STATUTORY POWER
OF SALE (as permitted by law), in addition to all other rights and remedies
given to Select Energy as mortgagee and secured party under the laws of the
State of New Hampshire and this Mortgage. Select Energy shall have the power to
sell, lease or otherwise dispose of the Mortgaged Property or any part thereof
in one or more parcels at public or, for items not constituting real property,
private sale, at any exchange, broker's board or at any office of Select Energy
or elsewhere, for cash, on credit or for future delivery and at such price or
prices and upon such other terms as is commercially reasonable. Any notice
required by law of sale or other disposition of any of the Mortgaged Property
not constituting real property by Select Energy shall be deemed reasonable if
given ten (10) days or more prior to the time of any public sale or the time
after which any private sale is to be made. GBP covenants that in case of a sale
in accordance with the terms of this Section 5.3, GBP, or any person in
possession, shall forthwith deliver possession to the purchaser at such sale, or
be summarily dispossessed, to the extent permitted under applicable law.

         5.4      RECEIPT SUFFICIENT DISCHARGE TO PURCHASE. Upon any sale of the
Mortgaged Property or any part thereof or any interest therein, whether pursuant
to foreclosure or power of sale or otherwise, the receipt of the officer making
the sale under judicial proceedings or of Select Energy shall be a sufficient
discharge to the purchaser for the purchase money, and such purchaser shall not
be obliged to see to the application thereof.

         5.5      SALE A BAR AGAINST GBP. Any sale of the Mortgaged Property or
any part thereof or any interest therein pursuant to this Mortgage, whether
pursuant to lawful foreclosure or lawful power of sale, shall forever be a
perpetual bar against GBP to assert any claim of ownership to the Mortgaged
Property or such part thereof or such interest therein.

         5.6      APPLICATION OF PROCEEDS OF SALE. The proceeds of any sale of
the Mortgaged Property or any part thereof or any interest therein, whether
pursuant to foreclosure or power of sale or otherwise hereunder, together with
any moneys at the time held by GBP as part of the Mortgaged Property, shall be
applied as provided in Section 6.2 hereof.

         5.7      REMEDIES, ETC. CUMULATIVE. Each right, power and remedy of
Select Energy provided for in this Mortgage or the Purchase Agreement or now or
hereafter existing at law or in equity or by statute or otherwise shall be
cumulative and concurrent and shall be in addition to




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every other right, power or remedy provided for in this Mortgage, or now or
hereafter existing at law or in equity or by statute or otherwise, and the
exercise or beginning of the exercise by any Person of any one or more of the
rights, powers or remedies provided for in this Mortgage or now or hereafter
existing at law or in equity or by statute or otherwise shall not preclude the
simultaneous or later exercise by such Person of any or all such other rights,
powers or remedies. No provision of this Mortgage shall be deemed to grant third
party beneficiary rights to any Person, other than Select Energy.

         5.8      CERTIFICATE AS TO NO MORTGAGE DEFAULT, ETC.; INFORMATION. Each
of GBP and Select Energy will deliver to the other, within twenty (20) days
following receipt of a written request therefor, a certificate stating that it
has no knowledge after due inquiry of any Mortgage Default hereunder or, if any
Mortgage Default has occurred and is continuing, specifying the nature and
period of existence thereof and, in the case of GBP, what action GBP is taking
or proposes to take with respect thereto.

         5.9      COMPROMISE OF ACTIONS, ETC. Any action, suit or proceeding
brought by Select Energy pursuant to this Mortgage or otherwise, and any claim
made by Select Energy under this Mortgage or otherwise, may be compromised,
withdrawn or otherwise dealt with by Select Energy without any notice to or
approval of GBP.

         5.10     NO WAIVER, ETC. No failure by Select Energy to insist upon the
strict performance of any term of this Mortgage or to exercise any right, power
or remedy consequent upon a breach thereof, shall constitute a waiver of any
such term or of any such breach. No waiver of any breach shall affect or alter
this Mortgage, which shall continue in full force and effect with respect to any
other then existing or subsequent breach. No action or inaction on the part of
GBP shall adversely affect or limit in any way the rights of Select Energy under
this Mortgage.

         5.11     RECEIPT AFTER COMMENCEMENT OF FORECLOSURE. Receipt and
acceptance by Select Energy, after the commencement of foreclosure proceedings,
of anything of value (other than payment in full) to be applied on or to the
Secured Obligations shall not constitute a waiver of the rights of foreclosure
by Select Energy.

         5.12     TERMS SUBJECT TO APPLICABLE LAW. All rights, powers and
remedies provided in this Mortgage may be exercised only to the extent that the
exercise thereof is not unlawful, and are intended to be limited to the extent
necessary so that they will not render this Mortgage invalid, unenforceable or
not entitled to be recorded, registered or filed under any applicable law. If
any term of this Mortgage or any application thereof shall be held to be
invalid, illegal or unenforceable, the validity of other terms of this Mortgage
or any other application of such terms shall in no way be affected thereby.

         5.13     LIMITATION ON INTEREST. All agreements between GBP and Select
Energy, whether now existing or hereafter arising and whether written or oral,
are hereby limited so that in no contingency shall any interest contracted for,
charged or received by Select Energy exceed the maximum amount permissible under
applicable law. If, from any circumstance whatsoever, interest would otherwise
be payable to Select Energy in excess of the maximum lawful amount, the interest
payable to Select Energy shall be reduced to the maximum amount permitted Select




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Energy under applicable law; and if from any circumstance Select Energy shall
ever receive anything of value deemed interest by applicable law in excess of
the maximum lawful amount, an amount equal to any excessive interest shall be
refunded to GBP, or applied to any other lawful amounts then due and owing by
GBP to Select Energy.

                                   ARTICLE VI

                      RECEIPT, DISTRIBUTION AND APPLICATION
                    OF CASH AND PROCEEDS FROM THE COLLATERAL

         6.1      CASH HELD BY SELECT ENERGY: INVESTMENTS. Unless otherwise
provided herein, any cash held by Select Energy under this Mortgage shall (until
applied to any Secured Obligations then due) be deposited and held by Select
Energy in a separate bank deposit account as security for the Secured
Obligations. Any amounts held by Select Energy the application of which is not
then required by the provisions of this Mortgage, may be invested and reinvested
by Select Energy in money market and similar investments. All interest received
by Select Energy with respect to any such investments shall be held by Select
Energy for application in the same manner as the amounts upon the investment of
which such interest was earned and may be liquidated as necessary for the
application of such amounts so held and invested as may be required hereunder.
All commissions and other costs and expenses incurred by Select Energy in
connection with the acquisition or disposition by it of any such investments may
be deducted by Select Energy from the interest received by Select Energy with
respect thereto.

         6.2      DISTRIBUTION OF AMOUNTS RECEIVED AFTER A MORTGAGE DEFAULT. All
amounts received and realized by Select Energy after a Mortgage Default shall
have occurred and be continuing, as well as all amounts then held or thereafter
received by Select Energy as part of the Mortgaged Property, shall be delivered
to Select Energy and distributed by Select Energy first to payment of the
expenses of any foreclosure hereunder, then for payment and performance of the
Secured Obligations, and the balance to GBP. In the event of any redemption of
the Mortgaged Property by GBP pursuant to a right of redemption granted by the
law of the State of New Hampshire subsequent to commencement of foreclosure
proceedings by Select Energy, the redeeming party shall pay all advances, costs
and expenses (including reasonable attorney's fees) incurred by Select Energy in
connection with such foreclosure proceedings to the date of redemption.

                                  ARTICLE VII

                   SUPPLEMENTS AND AMENDMENTS TO THIS MORTGAGE

         7.1      CONDITIONS AND LIMITATIONS. This Mortgage may only be
supplemented or amended by the execution and delivery by GBP and Select Energy
of a written instrument, which shall be duly recorded in the Rockingham County
Registry of Deeds.

                                  ARTICLE VIII

                            FURTHER ASSURANCES, ETC.



                                       11
<PAGE>   13


         8.1      FURTHER ASSURANCES. GBP at GBP's expense will duly execute,
acknowledge and deliver all such conveyances, mortgages, security interests,
pledges, assignments, assurances and other instruments and take all such other
action as Select Energy from time to time may reasonably request (a) to subject
to the mortgage lien or security interest created by this Mortgage all or any
portion of the Mortgaged Property, (b) to perfect, publish notice or protect the
validity of the mortgage lien or security interest created by this Mortgage, (c)
to preserve and defend the title of GBP to the Mortgaged Property and the rights
of Select Energy therein against the claims of all Persons so long as this
Mortgage shall remain undischarged, or (d) further to effect the purposes of
this Mortgage and to carry out the terms hereof or better to assure and confirm
to Select Energy its rights, powers and remedies hereunder.

         8.2      DEFEASANCE AND RELEASE, ETC. Notwithstanding anything to the
contrary in this Mortgage, upon the performance in full of GBP's obligation to
deliver the Prepaid Seabrook Power to Select Energy or to make payment in lieu
thereof (together with all other amounts due with respect to the Prepaid
Seabrook Power, if any), in accordance with Sections 7.2 and 7.3 of the Purchase
Agreement, Select Energy will execute and deliver to GBP, at the request and
expense of GBP, a proper instrument or instruments (including without limitation
appropriate termination statements) acknowledging the satisfaction and discharge
of the mortgage lien and security interest created by this Mortgage and will
duly release, discharge, transfer and deliver to GBP, or to whomsoever may be
lawfully entitled thereto, the property constituting the Mortgaged Property then
held by Select Energy as mortgagee and secured party.

                                   ARTICLE IX

                           EXCLUSIVITY; NOTICES, ETC.

         9.1      EXCLUSIVITY. The parties hereby acknowledge and agree that the
provisions set forth in this Mortgage shall constitute the sole provisions
governing the granting of security by GBP with respect to the Secured
Obligations and the exercise of remedies by Select Energy or its successor in
connection therewith so long as this Mortgage remains in effect, and that any
provisions in the Master Power Purchase and Sale Agreement dated as of February
5, 2001, by and between GBP and Select Energy (the "Master Power Purchase
Agreement") related to the subject matter of this Mortgage, whether or not
consistent with the terms hereof, shall not apply so long as this Mortgage
remains in effect.

         9.2      NOTICES, DIRECTIONS, ETC. All notices and other communications
hereunder shall be in writing and mailed by United States mail, telexed,
telecopied or delivered by hand to the applicable person at the addresses
indicated below:

         (i)      if to GBP:

                  Great Bay Power Corporation
                  222 International Drive
                  Portsmouth, NH 03801
                  Attn: Frank W. Getman, Jr., President & CEO




                                       12
<PAGE>   14


         (ii)     if to Select Energy:

                  107 Selden Street
                  Berlin, Connecticut  06037
                  Attn: David R. McHale, Vice President and Treasurer

         All such notices and other communications so mailed, telexed,
telecopied or delivered, shall be deemed given or delivered when received it
sent by mail, or when delivered if sent by telecopy, telex or delivered by hand.

         9.3      SEVERABILITY. Any provision of this Mortgage which is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions thereof or hereof, and any such
prohibition or unenforceability in any jurisdiction shall not invalidate or
render unenforceable such provision in any other jurisdiction.

         9.4      SUCCESSORS AND ASSIGNS. No assignment, pledge or other
transfer of this Mortgage or the Mortgaged Property by either party may be made
without prior written consent of the other party, which consent shall not be
unreasonably withheld. This Mortgage shall be binding upon and inure to the
benefit of, and may be performed by, the successors and assigns of the parties,
except that no assignment, pledge or other transfer of this Mortgage by either
party shall operate to release the assignor or transferor from any of its
obligations under this Mortgage unless: (1) consent to the release is given in
writing by the other party; (2) such transfer is incident to a merger or
consolidation with, or transfer of all or substantially all of the assets of the
transferor to another person or business entity which shall, as part of such
succession, assume all the obligations of the transferor under this Mortgage.

         9.5      MISCELLANEOUS. The construction, performance, enforcement and
validity of this Mortgage shall be governed by and determined in all respects
under the laws of the State of New Hampshire. The headings in this Mortgage are
for purposes of reference only and shall not limit or otherwise affect the
meaning hereof.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]



                                       13


<PAGE>   15



         IN WITNESS WHEREOF, GBP and Select Energy have caused this Mortgage to
be executed by an officer duly authorized on the date first above written.



                                 GREAT BAY POWER CORPORATION


                                 By: /s/ Frank W. Getman Jr.
                                     ------------------------------------------
                                     Frank W. Getman Jr.
                                     Its President & CEO


                                 NORTHEAST UTILITIES SERVICE CO.,
                                 AS AGENT FOR SELECT ENERGY, INC.

                                 By: /s/ Randy Shoop
                                     ------------------------------------------
                                     Randy Shoop
                                     Assistant Treasurer





                                       14
<PAGE>   16


STATE OF New Hampshire              )
                                    : ss:                      DATE:
COUNTY OF                           )
          ---------------------

         Then personally appeared before me Frank W. Getman, Jr., who being by
me duly sworn, acknowledged that he is the President and CEO of Great Bay Power
Corporation, and acknowledged the foregoing instrument to be the free act and
deed of said Great Bay Power Corporation.


                                        -----------------------------------
                                        Notary Public



My Commission Expires:
                        ---------------------


STATE OF CONNECTICUT                )
                                    : ss:  Berlin                       DATE:
COUNTY OF HARTFORD                  )

         Then personally appeared before me Randy Shoop, who being by me duly
sworn, acknowledged that he is the Assistant Treasurer of Northeast Utilities
Service Co., Agent for Select Energy, Inc., and acknowledged the foregoing
instrument to be the free act and deed of said Northeast Utilities Service Co.
in said capacity as Agent for Select Energy, Inc.


                                        -----------------------------------
                                        Notary Public


My Commission Expires:
                        ---------------------



                                       15
<PAGE>   17



                                    EXHIBIT A

                                   DEFINITIONS

         The following terms used in the Mortgage to which this Exhibit A is
attached shall have the respective meanings set forth below; definitions
expressed in the singular shall import the plural and vice versa. All
definitions of agreements or other instruments shall mean such agreements as
modified or amended in accordance with the terms thereof and of this Mortgage,
or as replaced in accordance with the terms of the Purchase Agreement and this
Mortgage.

         "BUSINESS DAY" shall mean any day that is not a Saturday, Sunday or
legal holiday in the State of New Hampshire or a day on which banking
institutions chartered by the State of New Hampshire or the United States are
legally required or authorized to close.

         "CONSENTS" shall mean (i) the appropriate consents of all parties
(other than GBP) to the Purchase Agreement assigned pursuant to the Mortgage,
and (ii) appropriate consents, non-disturbance agreements and landlord waivers
of all Persons, if any, having any interest in the Mortgaged Property.

         "LEGAL REQUIREMENTS" shall mean, as to any Person or the Mortgaged
Property (or any part thereof) (i) all laws, rules, rulings, orders,
regulations, requirements, ordinances, judgments, decrees and injunctions of any
court or governmental agency or authority or any arbitrator applicable thereto,
or to the ownership, construction, use, occupancy, possession, operation or
maintenance thereof (including, without limitation, all of the foregoing
relating to environmental and zoning requirements), (ii) all requirements of
each insurance policy or performance bond in effect as of the date hereof
covering or applicable thereto or the use thereof and all requirements of the
issuer of each such policy or bond, (iii) all requirements or limitations of
each permit, license, approval, consent, registration and authorization (public
or private) relating thereto, or to the construction, ownership, use,
possession, operation or maintenance thereof, (iv) all covenants, agreements,
restrictions and encumbrances contained in the Purchase Agreement or any
documents delivered thereunder as amended with the written consent of each party
thereto or holder of an interest therein in accordance with the terms thereof or
in any instrument either of record or known to GBP at the time in force
affecting the Mortgaged Property or any part thereof or the ownership,
construction, use, occupancy, possession or operation or maintenance thereof,
(v) all manufacturer's or suppliers, warranties and specifications, (vi) in the
case of any Person, the partnership agreement, certificate of incorporation,
by-laws or other organizational or governing documents of such Person.

         "LIEN" shall mean any mortgage, pledge, security interest, encumbrance,
lien or charge of any kind (including any agreement to give any of the
foregoing), any conditional sale or other title retention agreement or any lease
in the nature thereof.

         "PERMITTED ENCUMBRANCES" shall mean any of the following:

         (i)      Liens for taxes, assessments and other governmental charges
not due and payable or which can be paid without penalty or in installments, or
which are currently being contested in





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<PAGE>   18

good faith by appropriate proceedings (unless such contest involves a material
risk that the Mortgaged Property or any part thereof, title thereto or any
interest therein may be sold, lost or forfeited or the use of the Mortgaged
Property interfered with); provided, GBP shall have set aside on its books
adequate reserves with respect to any such tax, assessment or other governmental
charge so being contested;

         (ii)     mechanics' and materialmen's Liens not filed of record and
charges not delinquent incident to current construction which have been filed of
record but which are being contested in good faith and have not proceeded to
judgment (unless such contest involves a material risk that the Mortgaged
Property or any part thereof, title thereto or any interest therein may he sold,
lost or forfeited or the use of the Mortgaged Property interfered with);
provided, GBP shall have set aside on its books adequate reserves with respect
to such mechanics' or materialmen's Liens so being contested;

         (iii)    workmen's, repairmen's, warehousemen's and carriers' Liens and
other similar Liens arising in the ordinary course of business for charges not
delinquent or which are currently being contested in good faith by appropriate
proceedings (unless such contest involves a material risk that the Mortgaged
Property or any part thereof, title thereto or any interest therein may be sold,
lost or forfeited or the use of the Mortgaged Property interfered with)
provided, GBP shall have set aside on its books adequate reserves with respect
to such Liens so being contested;

         (iv)     Liens in respect of judgments or awards with respect to which
GBP shall in good faith currently be prosecuting an appeal or proceedings for
review and with respect to which GBP shall have secured a stay of execution
pending such appeal or proceedings for review; provided, GBP shall have set
aside an its books adequate reserves with respect to any such judgments or
awards;

         (v)      easements, rights of way, exceptions, encroachments,
reservations, restrictions, conditions or limitations which do not in the
aggregate materially interfere with or impair the operation or use of the
property affected thereby for the purposes for which it is or may reasonably be
expected to be held by GBP;

         (vi)     rights reserved to, or vested in, any municipality or
governmental or other public authority by the terms of any right, power,
franchise, grant, license or permit to control or regulate any part of the
Mortgaged Property or to use such property in any manner which does not in the
aggregate materially interfere with or impair the operation or use thereof for
the purposes for which it is or may reasonably he expected to be held by GBP;

         (vii)    any obligations or duties, affecting any part of the Mortgaged
Property, to any municipality or governmental or other public authority with
respect to any franchise, grant, license, consent or permit which do not in the
aggregate materially interfere with or impair the operation or use of such
property;

         (viii)   present or future valid zoning laws and ordinances, which do
not interfere with or impair the operation or use of the property affected
thereby for the purposes for which it is or may reasonably be expected to be
held by GBP;




                                       17

<PAGE>   19


         (ix)     deposits or pledges to secure bids, tenders, contracts (other
than contracts for the payment of money), leases, statutory obligations, surety
and appeal bonds and other obligations of like nature arising in the ordinary
course of business;

         (x)      the mortgage liens and security interests to secure GBP's
obligations under the Purchase Agreement; and

         (xi)     the terms of the JOA.

         "PERSON" shall mean any individual, corporation, partnership, joint
venture, trust, unincorporated organization or any other judicial entity, or any
foreign state or agency or political subdivision thereof.





                                       18
<PAGE>   20



                                   SCHEDULE 1

                               DESCRIPTION OF LAND

The tract of land with the buildings and other improvements thereon situated on
the easterly side of U.S. Route I in Seabrook, County of Rockingham, State of
New Hampshire, shown as Lot 1 on a plan entitled "Subdivision Plan of Land
Properties Inc. & Public Service Co. of N.H. Seabrook, N.H." dated December 5,
1978 and recorded in the Rockingham County Registry of Deeds, Plan No. D8560,

excluding therefrom all land and rights excepted, excluded or reserved as
described in the following five deeds (the "Five Deeds") to EUA Power
Corporation:

         (1)      Deed of Central Maine Power Company to EUA Power Corporation,
         dated November 21, 1986 and recorded on November 25, 1986 at the
         Rockingham County Registry of Deeds, Book 2645, Page 601, conveying a
         6.04178% undivided fee simple interest in the property described
         therein;

         (2)      Deed of Central Vermont Public Service Corporation to EUA
         Power Corporation, dated November 21, 1986 and recorded on November 25,
         1986 at the Rockingham County Registry of Deeds, Book 2645, Page 688,
         conveying a 1.59096% undivided fee simple interest in the property
         described therein;

         (3)      Deed of Bangor Hydro-Electric Company to EUA Power
         Corporation, dated November 21, 1986 and recorded on November 25, 1986
         at the Rockingham County Registry of Deeds, Book 2645, Page 651,
         conveying a 2.17391% undivided fee simple interest in the property
         described therein;

         (4)      Deed of Maine Public Service Company to EUA Power Corporation,
         dated November 21, 1986 and recorded on November 25, 1986 at the
         Rockingham County Registry of Deeds, Book 2645, Page 723, conveying a
         1.46056% undivided fee simple interest in the property described
         therein;

         (5)      Deed of Fitchburg Gas and Electric Light Company to EUA Power
         Corporation, dated November 21, 1986 and recorded on November 25, 1986
         at the Rockingham County Registry of Deeds, Book 2645, Page 758,
         conveying a .86519% undivided fee simple interest in the property
         described therein

and subject to and together with the benefit of all rights, easements and
agreements encumbering or appurtenant to said tract of land located in the Towns
of Seabrook, Hampton Falls and/or Hampton, Rockingham County, New Hampshire,
which are set forth or referred to in the Five Deeds.

         Meaning and intending to describe and mortgage as part of the Mortgaged
Property all and the same premises conveyed to EUA Power Corporation by the Five
Deeds.


                                       19