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                                                                EXHIBIT 10.58(a)


                                                                [EXECUTION COPY]

                                 FIRST AMENDMENT


                  FIRST AMENDMENT, dated as of December 17, 1999 (this
"Amendment"), to the Credit Agreement, dated as of September 8, 1999 (as
amended, supplemented or otherwise modified from time to time, the "Credit
Agreement"), among Cogentrix Eastern America, Inc., a Delaware corporation (the
"Borrower"), the several banks and other financial institutions or entities from
time to time parties to the Credit Agreement (the "Lenders"), and Dresdner Bank,
AG, New York Branch, as administrative agent for the Lenders (in such capacity,
the "Administrative Agent").

                              W I T N E S S E T H:


                  WHEREAS, the Borrower, the Lenders and the Administrative
Agent are parties to the Credit Agreement; and

                  WHEREAS, the Borrower has requested that the Lenders agree to
amend certain provisions of the Credit Agreement, and the Lenders are agreeable
to such request but only upon the terms and subject to the conditions set forth
herein;

                  NOW, THEREFORE, in consideration of the premises and mutual
agreements contained herein, and for other valuable consideration the receipt of
which is hereby acknowledged, the Borrower, the Lenders and the Administrative
Agent hereby agree as follows:

                  1. Definitions. All terms defined in the Credit Agreement
shall have such defined meanings when used herein unless otherwise defined
herein.

                  2. Amendment of Section 1.1. Section 1.1 of the Credit
Agreement is hereby amended by adding the following definition between
"Insolvent" and "Interest Payment Date":

                  "`Intercompany Notes': the collective reference to (i) the
                  Promissory Note, payable by Thaleia, LLC to the order of the
                  Borrower in the amount of $36,646,000.00, dated as of
                  September 20, 1999; (ii) the Promissory Note, payable by
                  Thaleia, LLC to the order of the Borrower in the amount of
                  $39,800,000.00, dated as of June 2, 1999; (iii) the Promissory
                  Note, payable by Cogentrix/Scrubgrass, Inc. to the order of
                  the Borrower in the amount of $13,389,143.00, dated as of
                  October 20, 1998; (iv) the Promissory Note, payable by the
                  Northampton Holdco to the order of the Borrower in the amount
                  of $13,967,792.00, dated as of October 20, 1998; (v) the
                  Promissory Note, payable by the Logan Holdco to the order of
                  the Borrower in the amount of $79,194,864.00, dated as of
                  October 20, 1998; and (vi) the Promissory Note, payable by the
                  Carneys Point Holdco to the order of the Borrower in the
                  amount of $21,998,000.00, dated as of October 20, 1998."

                  3. Amendment of Section 3.16. Section 3.16 of the Credit
Agreement is hereby amended by inserting the following language after the phrase
"when stock certificates


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representing such Pledged Stock are delivered to the Administrative Agent," in
the second sentence of such section:

                  "in the case of the Intercompany Notes, when such notes are
                  delivered to the Administrative Agent,"

                  4. Amendment of Subsection 6.1(a). Subsection 6.1(a) of the
Credit Agreement is hereby amended by deleting the language after the word
"except," and substituting in the place of such language the following language:

                  "(i) in the case of the Borrower, Indebtedness incurred under
                  any Credit Document and (ii) in the case of the Significant
                  Subsidiary Holding Companies, Indebtedness incurred under the
                  Intercompany Notes."

                  5. Amendment of Subsection 9.1(b). Subsection 9.1(b) of the
Credit Agreement is hereby amended by deleting clause (i) of the proviso to the
second sentence of such subsection, and replacing such clause with the following
new clause (i):

                  " (i) forgive any portion of the principal amount or extend
                  the final scheduled date of maturity of any Revolving Loan, or
                  increase the amount or extend the expiration date of any
                  Lender's Revolving Commitment, or reduce any interest or fees
                  with respect to any Revolving Loan, in each case without the
                  consent of each Lender directly affected thereby;"

                  6. Representations and Warranties. To induce the
Administrative Agent and the Lenders to enter into this Amendment, the Borrower
hereby represents and warrants to the Administrative Agent and all of the
Lenders as of the Amendment Effective Date (as defined below) that:

                  (a) The representations and warranties of each Credit Party
                  set forth in each of the Credit Documents (as amended hereby)
                  are true and correct in all material respects on and as of the
                  Amendment Effective Date with the same effect as if made on
                  and as of such date, except for representations and warranties
                  expressly stated to relate to a specific earlier date, in
                  which case such representations and warranties were true and
                  correct in all material respects as of such earlier date (it
                  being understood that the references to the Credit Documents
                  in such representations and warranties shall be deemed to be
                  references to the Credit Documents as amended by the Amendment
                  Documents (as defined below));

                  (b) No Default or Event of Default shall have occurred and be
                  continuing after giving effect to the Amendment Documents;

                  (c) The Borrower has the corporate power and authority, and
                  the legal right, to make, deliver the Amendment Documents and
                  to perform the Credit Documents, as amended by the Amendment
                  Documents, and has taken all necessary corporate


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                  action to authorize the execution, delivery and performance of
                  such Amendment Documents and the performance of such Credit
                  Documents, as so amended;

                  (d) No consent or authorization of, approval by, notice to,
                  filing with or other act by or in respect of, any Governmental
                  Authority or any other Person is required in connection with
                  the execution and delivery of the Amendment Documents or with
                  the performance, validity or enforceability of the Credit
                  Documents, as amended by the Amendment Documents;

                  (e) Each Amendment Document has been duly executed and
                  delivered on behalf of the Borrower;

                  (f) Each Amendment Document and each Credit Document to which
                  it is a party, as amended by the Amendment Documents,
                  constitutes a legal, valid and binding obligation of the
                  Borrower enforceable against the Borrower in accordance with
                  its terms, except as affected by bankruptcy, insolvency,
                  fraudulent conveyance, reorganization, moratorium and other
                  similar laws relating to or affecting the enforcement of
                  creditors' rights generally and by general equitable
                  principles (whether considered in a proceeding in equity or at
                  law); and

                  (g) The execution, delivery and performance of the Amendment
                  Documents and the performance of the Credit Documents, as
                  amended by the Amendment Documents, will not violate any
                  Requirement of Law or Contractual Obligation of the Borrower
                  or of any of its Subsidiaries and will not result in, or
                  require, the creation or imposition of any Lien on any of its
                  or their respective properties or revenues pursuant to any
                  such Requirement of Law or Contractual Obligation.

For purposes of this Amendment, the "Amendment Documents" means the collective
reference to this Amendment and each of the amendments referred to in clauses
(ii), (iii) and (iv) of Section 7(a) of this Amendment.

                  7. Conditions to Effectiveness. This Amendment shall not
become effective until the date (such date, the "Amendment Effective Date") as
of which all of the following conditions precedent shall have been satisfied:
(a) the Administrative Agent shall have received each of the following: (i)
counterparts of this Amendment, duly executed and delivered by the Borrower and
each of the Lenders; (ii) Amendment No. 1 to the Security Deposit Agreement in
the form attached hereto as Exhibit A, duly executed and delivered by the
Borrower and each of the Significant Subsidiary Holding Companies; (iii)
Amendment No. 1 to the Northampton Holdco Stock Pledge Agreement in the form
attached hereto as Exhibit B, duly executed and delivered by the Borrower; (iv)
Amendment No. 1 to the Logan Holdco Stock Pledge Agreement in the form attached
hereto as Exhibit C, duly executed and delivered by the Borrower; and (b) the
Administrative Agent shall have received each of the Intercompany Notes pursuant
to such Amendment No. 1 to the Security Deposit Agreement, together with an
undated note power or endorsement for each Intercompany Note executed in blank
by a duly authorized officer of the Borrower.


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                  8. Limited Effect. Except as expressly amended herein, the
Credit Agreement shall continue to be, and shall remain, in full force and
effect. This Amendment shall not be deemed to be a waiver of, or consent to, or
a modification or amendment of, any other term or condition of any of the Credit
Documents or to prejudice any other right or rights which the Lenders may now
have or may have in the future under or in connection with any of the Credit
Documents or any of the instruments or agreements referred to therein, as the
same may be amended from time to time.

                  9. Costs and Expenses. The Borrower agrees to pay or reimburse
the Administrative Agent for all its reasonable and customary outofpocket costs
and expenses incurred in connection with this Amendment, including, without
limitation, the reasonable fees and disbursements of Simpson Thacher & Bartlett,
counsel for the Administrative Agent.

                  10. Counterparts. This Amendment may be executed by one or
more of the parties hereto in any number of separate counterparts, and all of
said counterparts taken together shall be deemed to constitute one and the same
instrument.

                  11. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

                  IN WITNESS WHEREOF, the parties hereto have caused this
Amendment to be executed and delivered by their respective duly authorized
officers as of the date first above written.


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                                             COGENTRIX EASTERN AMERICA, INC.



                                             By: /s/ Thomas F. Schwartz
                                                 -------------------------------
                                                 Title: Senior Vice President-
                                                        Finance and Treasurer

                                             DRESDNER BANK AG, NEW YORK BRANCH,
                                              as Administrative Agent and Lender



                                             By: /s/ Andrew Schroeder
                                                 -------------------------------
                                                 Title: Vice President


                                             By: /s/ Robert F. Moyle
                                                 -------------------------------
                                                 Title: Vice President