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                                                                   EXHIBIT 99.4



                    PIONEER AMERICAS ACQUISITION CORPORATION

                               OFFER TO EXCHANGE
                   UP TO $200,000,000 IN PRINCIPAL AMOUNT OF
              9 1/4% SERIES A SENIOR SECURED NOTES DUE 2007 ISSUED
                        AND SOLD IN A TRANSACTION EXEMPT
                   FROM REGISTRATION UNDER THE SECURITIES ACT
                              OF 1933, AS AMENDED
                                      FOR
                      $200,000,000 IN PRINCIPAL AMOUNT OF
                 9 1/4% SERIES B SENIOR SECURED NOTES DUE 2007


To Securities Dealers, Commercial Banks
  Trust Companies and Other Nominees:

         Enclosed for your consideration is a Prospectus dated _______ , 1997
(as the same may be amended or supplemented from time to time, the
"Prospectus") and a form of Letter of Transmittal (the "Letter of Transmittal")
relating to the offer (the "Exchange Offer") by Pioneer Americas Acquisition
Corporation (the "Company") and all of the subsidiaries of the Company
(together with the Company, the "Issuers") to exchange up to $200,000,000 in
principal amount of its 9 1/4% Series A Senior Secured Notes due 2007 issued
and sold in a transaction exempt from registration under the Securities Act of
1933, as amended (the "Original Notes"), for $200,000,000 in principal amount
of its 9 1/4% Series B Senior Secured Notes due 2007 (the "Exchange Notes").

         We are asking you to contact your clients for whom you hold Original
Notes registered in your name or in the name of your nominee. In addition, we
ask you to contact your clients who, to your knowledge, hold Original Notes
registered in their own name. The Issuers will not pay any fees or commissions
to any broker, dealer or other person in connection with the solicitation of
tenders pursuant to the Exchange Offer. You will, however, be reimbursed by the
Issuers for customary mailing and handling expenses incurred by you in
forwarding any of the enclosed materials to your clients. The Issuers will pay
all transfer taxes, if any, applicable to the tender of Original Notes to it or
its order, except as otherwise provided in the Prospectus and the Letter of
Transmittal.

         Enclosed are copies of the following documents:

         1.     The Prospectus;

         2.     A Letter of Transmittal for your use in connection with the
                tender of Original Notes and for the Information of your
                clients;

         3.     A form of letter that may be sent to your clients for whose
                accounts you hold Original Notes registered in your name or the
                name of your nominee, with space provided for obtaining the
                clients' instructions with regard to the Exchange Offer;

         4.     A form of Notice of Guaranteed Delivery; and

         5.     Guidelines for Certification of Taxpayer Identification Number
                on Substitute Form W-9.

         Your prompt action is requested. The Exchange Offer will expire at
5:00 p.m., Eastern Standard Time, on _________, ________ __, 1997, unless
extended (the "Expiration Date"). Original Notes tendered pursuant to the
Exchange Offer may be withdrawn, subject to the procedures described in the
Prospectus, at any time prior to the Expiration Date.

         To tender Original Notes, certificates for Original Notes or a
Book-Entry Confirmation, a duly executed and properly completed Letter of
Transmittal or a facsimile thereof, and any other required documents, must be
received by the Exchange Agent as provided in the Prospectus and the Letter of
Transmittal.

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         Additional copies of the enclosed material may be obtained from United
States Trust Company of New York, the Exchange Agent, by calling (800)
548-6565.

         NOTHING HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU OR
ANY PERSON AS AN AGENT OF THE ISSUERS OR THE EXCHANGE AGENT, OR AUTHORIZE YOU
OR ANY OTHER PERSON TO MAKE ANY STATEMENTS ON BEHALF OF EITHER OF THEM WITH
RESPECT TO THE EXCHANGE OFFER, EXCEPT FOR STATEMENTS EXPRESSLY MADE IN THE
PROSPECTUS AND THE LETTER OF TRANSMITTAL.