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                                                               EXHIBIT 10.10(a)

                    FOURTH AMENDMENT TO COAL SALES AGREEMENT 

         THIS FOURTH AMENDMENT TO COAL SALES AGREEMENT ("Amendment") is made and
entered into as of the first day of July, 1998 to amend that certain Coal Sales
Agreement dated as of February 15, 1990, as amended by Amendments First, Second
and Amendment and Clarification, among ELECTRIC FUELS CORPORATION, KENTUCKY MAY
COAL COMPANY, INC. AND COGENTRIX OF RICHMOND, INC. ("Coal Sales Agreement").

                                  WITNESSETH: 

         WHEREAS, the parties to the Coal Sales Agreement have determined that
certain terms and provisions of the Coal Sales Agreement should be amended; and

         WHEREAS, the Coal Sales Agreement provides that it may be amended only
by an instrument in writing signed by all parties.

         NOW, THEREFORE, for good and valuable consideration including the
mutual agreements contained herein, the parties to the Coal Sales Agreement do
hereby agree as follows:

                  1. Section 3.02 of the Coal Sales Agreement is hereby amended
         by the addition of a new provision as subsection (e) as follows:

         "(e) In addition to the foregoing provisions of subsection 3.02(a),
         Seller may request approval of one or more Substitute Supply Source for
         future use as a source of Substitute Coal. Buyer shall evaluate each
         such request and, in its sole judgment, determine if the proposed
         source is acceptable as a Substitute Supply Source to provide
         Substitute Coal. Buyer shall promptly notify Seller if the proposed
         source is accepted as a Substitute Supply Source and, if approved, it
         shall continue to be a Substitute Supply Source unless and until Buyer
         notifies Seller it is no longer an accepted Substitute Supply Source.
         Buyer may withdraw such acceptance of a source as a Substitute Supply
         Source if, in its sole determination, it concludes the Substitute Coal
         from that source does not meet the requirements of the Agreement or
         otherwise is less desirable to the Facility than coal supplied from the
         Source Complex. Substitute Coal may be delivered on a continuous basis
         or interspersed with deliveries from the Source Complex; provided,
         however, that interspersed delivery of Substitute Coal does not cause
         operational difficulties, increased operating costs or otherwise
         adversely impact the Facility. Buyer may suspend or preclude future
         interspersed deliveries of Substitute Coal from any or all Substitute
         Supply Sources by notice to Seller."

                  2. Section 4.01 of the Coal Sales Agreement is hereby amended
         by deleting the second sentence thereof (set forth in Amendment and
         Clarification) and inserting in its place the following:


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         "The "Base Price" per ton of coal supplied hereunder on and after July
         1, 1998, shall be $[***] F.O.B. railroad cars at the Source Complex."

                  3. Section 4.02 (a)(i) of the Coal Sales Agreement is hereby
         amended by deleting the third sentence thereof (set forth in Amendment
         and Confirmation) and inserting in its place the following:

                  "Notwithstanding the two preceding sentences, the BCP per ton
                  of coal supplied on and after July 1, 1998, shall be $[***]
                  per net ton."

                  4. Article IX of the Coal Sales Agreement is amended by the
         addition of a new provision as section 9.09 as follows:

                  "Section 9.09. E-Fuel. Buyer shall not be in violation of this
         Coal Sales Agreement by co-firing the Facility with E-Fuel; provided
         that during the term of this Coal Sales Agreement 100% of the coal
         content of such E-Fuel burned at the Facility is supplied to Buyer
         under this Agreement or otherwise supplied to Buyer by Seller under
         mutually accepted terms. This Section 9.09 shall apply only to E-Fuel.
         ("E-Fuel" is the process-engineered coal based fuel produced by the
         Duquesne Energy, Inc. proprietary process.)"

                  5. This Amendment is subject to and shall be effective only
         upon receipt of the approval of Buyer's lenders, which approval buyer
         shall immediately request and diligently pursue. If Buyer's lenders
         fail to approve this Amendment by October 31, 1998, either party may
         declare the Amendment null and void ab initio prior to receipt of said
         lender's consent.

                  6. Upon Buyer receiving lender's approval of this Amendment an
         adjustment payment for coal delivered to Buyer on and after July 1,
         1998, to adjust for the change in Base Coal Price provided by this
         Agreement, shall be included with the next ordinary payment to Seller
         under the Coal Sales Agreement.

                  7. Except as specifically provided in this Amendment, the
         terms and conditions set forth in the Coal Sales Agreement shall remain
         in full force and effect.

         WITNESS the due execution hereof as of July 1, 1998.

ELECTRIC FUELS CORPORATION

By: /s/ LS Meade Jr.
    ----------------------------
Title: SVP
       -------------------------




[***]    These portions of this exhibit have been omitted and filed separately
         with the Securities and Exchange Commission pursuant to a request for
         confidential treatment.
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KENTUCKY MAY COAL COMPANY, INC.

By: /s/ LS Meade Jr.
    ----------------------------
Title: DIRECTOR
       -------------------------

COGENTRIX OF RICHMOND, INC.

By: /s/ Dennis W. Alexander
    ----------------------------
Title: Group Senior VP
      --------------------------