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                                                                 Exhibit 10.37.6

                              AMENDMENT NO. 9 TO
                              ------------------
                        PURCHASE AND SALE AGREEMENT AND
                        -------------------------------
                           JOINT ESCROW INSTRUCTIONS
                           -------------------------
                           AND SIDE LETTER AGREEMENT
                           -------------------------


          THIS AMENDMENT NO. 9 TO PURCHASE AND SALE AGREEMENT AND JOINT ESCROW
INSTRUCTIONS AND SIDE LETTER AGREEMENT (this "Amendment") is made and entered
                                              ---------
into and effective as of March 14, 2000, by and between KAISER VENTURES INC., a
Delaware corporation and KAISER STEEL LAND DEVELOPMENT INC., a Delaware
corporation (collectively, "Seller"), and ONTARIO VENTURES I, LLC, a Delaware
                            ------
limited liability company ("Buyer").
                            -----

                                   RECITALS
                                   --------

          A.   WHEREAS, Buyer and Seller have entered into that certain Purchase
and Sale Agreement and Joint Escrow Instructions dated as of October 19, 1999 as
amended by that certain Amendment No. 1 to Purchase and Sale Agreement and Joint
Escrow Instructions and Side Letter Agreement dated as of November 2, 1999, by
that certain Amendment No. 2 to Purchase and Sale Agreement and Joint Escrow
Instructions and Side Letter Agreement dated as of November 12, 1999, by that
certain Amendment No. 3 to Purchase and Sale Agreement and Joint Escrow
Instructions and Side Letter Agreement dated as of November 19, 1999, by that
certain Amendment No. 4 to Purchase and Sale Agreement and Joint Escrow
Instructions and Side Letter Agreement dated as of November 30, 1999, by that
certain Amendment No. 5 to Purchase and Sale Agreement and Joint Escrow
Instructions And Side Letter Agreement dated as of February 4, 2000, and by that
certain Amendment No. 6 to Purchase and Sale Agreement and Joint Escrow
Instructions And Side Letter Agreement dated as of March 6, 2000, by that
certain Amendment No. 7 to Purchase and Sale Agreement and Joint Escrow
Instructions and Side Letter dated as of March 10, 2000, and by that certain
Amendment No. 8 to Purchase and Sale Agreement and Joint Escrow Instructions and
Side Letter dated as of March 13, 2000 (collectively, the "Purchase Agreement");
                                                           ------------------
and

          B.   WHEREAS, pursuant to the Purchase Agreement, Buyer and Seller
have entered into that certain Side Letter Agreement dated as of October 19,
1999 which side letter was amended by the amendments to the Purchase Agreement
described in Recital A above (as amended, the "Side Letter Agreement"), the form
                                               ---------------------
of which was attached to the Purchase Agreement as Exhibit DD; and
                                                   ----------

          C.   WHEREAS, Buyer and Seller desire to again amend the Side Letter
Agreement and the Purchase Agreement, as more particularly set forth herein.

          NOW, THEREFORE, in consideration of the mutual covenants and
agreements herein contained and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, Buyer and Seller
hereby agree as follows:


                                   AGREEMENT
                                   ---------
<PAGE>

     1.   Amendments.  The Purchase Agreement and Side Letter Agreement are
          ----------
hereby amended as follows:


          A.   The "Contingency Date" (as defined in Section 1.11 of the
                    ----------------
Purchase Agreement) shall be extended further to April 20, 2000, in
consideration for which the sum of One Hundred Thousand Dollars ($100,000) shall
be released to Seller as set forth in Section 3.1.2 below.

          B.   In the event that Escrow is not canceled as of the Contingency
Date (as herein extended), then on April 20, 2000, Buyer shall deposit into
Escrow and then cause to be released to Seller from Escrow as provided in
Section 3.1.2 below the additional sum of (i) Two Hundred Thousand Dollars
($200,000) if Buyer and DTSC have reached an agreement on a final Consent Order
for the former Kaiser Steel Mill, or (ii) the additional sum of Three Hundred
Thousand Dollars ($300,000) if Buyer and DTSC have not reached agreement on a
final Consent Order for the former Kaiser Steel Mill by such date (either sum
shall be herein referred to as the "April 20 Deposit"). Whether the DTSC and
                                    ----------------
Buyer have agreed upon a final Consent Order shall be evidenced by (x) a letter
executed and delivered by the DTSC stating that the DTSC is willing to execute
an attached Consent Order, without any change, modification or any contingency
other than modifying the name of the consenting party to be that of the entity
which purchases the Property, subject only to Buyer or its permitted assignee
taking title to the Real Property, and (y) a letter from Buyer to Seller stating
that Buyer or its permitted assignee will execute and deliver the Consent Order
attached to the DTSC's letter without any change, modification or amendment or
any contingency other than Buyer or its permitted assignee taking title to the
Real Property.

          C.   The "Closing Date" (as defined in Section 1.9 of the Purchase
                    ------------
Agreement) shall be June 15, 2000.

          D.   Section 3.1.2 of the Agreement is hereby revised to read in full
as follows:

               3.1.2  Disposition of Deposit. Any portion of the Deposit or the
                      ----------------------
     April 20 Deposit which has been released to Seller prior to the termination
     of the Agreement shall be retained by Seller and become non-refundable to
     Buyer, so long as Seller has not materially defaulted, including, without
     limitation, by not delivering the Deed. All amounts released to Seller
     shall be applicable to the Purchase Price. On December 17, 1999, the sum of
     Seventy-Five Thousand Dollars ($75,000.00) of the Deposit was released to
     Seller. On February 4, 2000, the sum of Seventy-Five Thousand Dollars
     ($75,000.00) of the Deposit was released to Seller. On March 14, 2000, an
     additional One Hundred Thousand Dollars ($100,000.00) of the Deposit shall
     be released to Seller. On April 21, 2000, if Escrow was not canceled prior
     to that date, the April 20 Deposit shall be released to the Seller.
     Following the Contingency Date, in the event this Agreement is terminated
     or the Close of Escrow fails to occur by reason of Buyer's default
     hereunder, the entire Deposit and the entire April 20 Deposit (including
     all interest thereon) shall constitute liquidated damages pursuant to
     Section 6.2 below. In the event this Agreement is terminated by reason of
     Seller's material default or the Close of Escrow fails to occur by reason
     of Seller's material default hereunder, then the Deposit and the entire
     April 20 Deposit (including all interest thereon) shall be returned to
     Buyer. Upon the Close of Escrow, the entire Deposit and

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     the entire April 20 Deposit (including all interest thereon) shall be
     credited towards the payment of the Purchase Price.

          E.   Section 4.7 of the Agreement is hereby revised to read in full as
follows:

               4.7  Termination by Buyer Prior to Contingency Date.  Buyer shall
                    ----------------------------------------------
     have the right, exercisable in Buyer's sole and absolute discretion at any
     time on or prior to the Contingency Date, to terminate this Agreement for
     any reason or no reason whatsoever. If Buyer shall, on or prior to the
     Contingency Date, deliver written notice of termination of this Agreement
     to Seller and Escrow Holder, then this Agreement shall terminate, Seller
     shall retain any portion of (i) the Deposit and (ii) the April 20 Deposit
     which have been released to Seller prior to the date of such termination,
     Escrow shall be canceled, Seller and Buyer shall each pay one-half (1/2) of
     all Title Company and Escrow cancellation fees, and Buyer and Seller shall
     have no further obligations to each other hereunder, except as otherwise
     expressly set forth herein. In that event, Buyer shall return to Seller all
     documents delivered to Buyer at the request of Seller. Buyer's failure to
     deliver written notice of Buyer's election to terminate this Agreement in
     accordance with this Section 4.7 shall constitute a waiver of Buyer's right
     to disapprove any matters set forth in this Article 4, except as expressly
     provided in Section 4.1, above.

          F.   Section 4.8 of the Agreement is hereby revised to read in full as
follows:

               4.8  Termination by Seller.  If Buyer disapproves any of (i) the
                    ---------------------
     Adjacent Property Indemnification and Other Agreements or (ii) the Permits
     or (iii) any of the Other Assumed Obligations and Liabilities, then Seller
     shall have the right, within fourteen (14) days after Buyer gives notice of
     such disapproval, to terminate this Agreement, in which event the Seller
     shall retain any portion of the Deposit and the April 20 Deposit which has
     been released to Seller prior to the termination of the Agreement as set
     forth in Section 3.1.2 hereof. Notwithstanding anything to the contrary,
     with respect to the following railroad obligation only, Buyer shall only be
     obligated to assume Kaiser Venture Inc.'s guaranty of and the obligation of
     Kaiser Recycling Corporation ("KRC") to "provide space for a rail storage
                                    ---
     yard sufficient to meet the needs of the Company," as required by Section
     2.2(A) of the Members Operating Agreement of West Valley MRF, LLC ("MRF")
                                                                         ---
     dated as of June 19, 1997 in accordance with and to the extent of the
     matters set forth below in this Section.  Such agreement is as follows:
     (a) MRF must use the Tar Pits Parcel for rail storage purposes to the
     extent set forth below; (b) Buyer will, without charge, grant to MRF
     through Escrow at the Close of Escrow, a nonexclusive easement, to be used
     by MRF to the extent the Tar Pits Parcel is not available for MRF's rail
     storage purposes, drafted by Buyer to MRF (but MRF shall pay any recording
     costs), KRC, or Seller granting to MRF the nonexclusive right to use the
     existing rail tracks on Parcel 5 of the Land (APN No. 229-291-29) for MRF's
     rail storage purposes (x) for a storage period not exceeding 48 hours,
     except that on weekends and holidays such period shall be extended to 72
     hours, (y) for storage of rail cars being delivered to or picked up from
     MRF, and (z) for an aggregate use at any one time not to exceed one and
     one-half (1-1/2) trains (hereinafter called "Rail Storage"), all subject to
                                                  ------------
     the conditions set forth below (the "Existing Track Easement"); (c) Buyer
                                          -----------------------
     shall, without charge, through Escrow at the Close of Escrow, grant to MRF
     a new, nonexclusive blanket easement pursuant to which MRF may, at its sole
     cost and expense, construct on such portions of the area of said Parcel 5
     of the Land on which there is no existing track as Buyer may reasonably
     approve, additional railroad track to be used for Rail Storage or

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     spur line purposes, subject to the conditions set forth below (the
     "Additional Track Easement"), so long as such tracks are (aa) in a location
      -------------------------
     reasonably approved by Buyer or its assigns after consultation with the
     MRF, (bb) available for use by Buyer and its assignees if not in use by or
     necessary for the operations of MRF, and (cc) are consistent with any and
     all rights granted to any party prior to the date of notification by MRF to
     Buyer or its assigns that MRF intends to construct such additional railroad
     track, including, without limitation, rights granted to Speedway
     Development Corporation or The California Speedway Corporation; and (d)
     Buyer shall, without charge, through Escrow at the Close of Escrow, grant
     to MRF, subject to the easement granted for the San Sevaine Channel, and
     subject to there being property which satisfies the condition set forth in
     this (d), a nonexclusive easement to construct (at MRF's sole cost and
     expense) additional railroad track to be used for Rail Storage or spur line
     purposes, subject to the conditions described below (the "San Sevaine Track
                                                               -----------------
     Easement"), so long as Buyer and its assigns may use such track if not in
     --------
     use by or necessary for the operations of MRF. Such easement shall only be
     used to the extent that the ultimate location and construction of the San
     Sevaine Channel is such that there exists, after such location and
     construction, a portion of the Land which lies east of the San Sevaine
                                                    ----
     Channel and west of the easterly boundary of the Land.  Buyer (at its cost)
                 ----
     and Seller (at its cost) shall negotiate in good faith the final form of
     each of such above-referenced easements on or prior to the Contingency
     Date.

          Buyer shall have the right to establish reasonable rules for the use
     and conduct of operations of the railroad and on the rail storage
     facilities, including provisions to ensure that no activity or construction
     undertaken by MRF shall cause Buyer or its assigns to incur any out-of-
     pocket third party cost or expense.

          At such time as the MRF begins to use any easement for Rail Storage,
     Buyer shall request that CSI and The California Speedway agree to increase
     the size of the Rail Transportation Committee to include a representative
     of the MRF.

          With respect to the Additional Track Easement and the San Sevaine
     Track Easement, such easements shall provide that they will not be
     exercised and used by the MRF if it is commercially reasonable to use the
     Tar Pits Parcel for Rail Storage.  The Parties agree that it shall be
     commercially unreasonable, among other things, to require the remediation
     of the Tar Pits Parcel in a manner other than the use of a capping
     strategy. In addition, Buyer and the MRF shall in good faith determine the
     final location of the additional track and switches to be constructed
     pursuant to the exercise of the rights granted pursuant to the Additional
     Track Easement and/or the San Sevaine Track Easement. Other than providing
     the Existing Track Easement, the Additional Track Easement and the San
     Sevaine Channel Easement, Buyer shall have no obligation to grant or convey
     any other real property or interest therein to Seller, the MRF or KRC
     pursuant to Section 2.2 (A).

          Seller hereby agrees that in no event shall Buyer assume any
     obligation of Seller or any related entity to expend money pursuant to any
     agreement relating to the MRF for any capital or operational cost relating
     to the rail operations of the MRF. Buyer shall have no obligation to
     contribute, grant or convey any other real property or interest therein to
     MRF or KRC pursuant to such Section 2.2(A).

          G.   Section 6.2. of the Agreement is hereby revised to read in full
     as follows:

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<PAGE>

               6.2  Default by Buyer.  IN THE EVENT THAT BUYER FAILS IN THE
                    ----------------
     PERFORMANCE OF ANY OF ITS OBLIGATIONS HEREUNDER FOLLOWING THE CONTINGENCY
     DATE BUT PRIOR TO THE CLOSE OF ESCROW, OR IN THE EVENT THAT THE CLOSE OF
     ESCROW SHALL FAIL TO OCCUR BY REASON OF A DEFAULT IN BUYER'S OBLIGATIONS
     HEREUNDER, THE PARTIES AGREE THAT IT WOULD BE IMPRACTICAL OR EXTREMELY
     DIFFICULT TO FIX, PRIOR TO SIGNING THIS AGREEMENT, THE ACTUAL DAMAGES WHICH
     WOULD BE SUFFERED BY SELLER IF BUYER FAILS TO PERFORM ITS OBLIGATIONS UNDER
     THIS AGREEMENT. THEREFORE, IN THE EVENT THAT THE CLOSE OF ESCROW SHALL FAIL
     TO OCCUR BY REASON OF A DEFAULT IN BUYER'S OBLIGATIONS HEREUNDER, SELLER
     SHALL BE ENTITLED, AS ITS SOLE AND EXCLUSIVE REMEDY FOR SUCH DEFAULT, TO
     IMMEDIATELY TERMINATE THIS AGREEMENT UPON SUCH DEFAULT, IN WHICH CASE THE
     SELLER SHALL RETAIN ANY PORTION OF THE DEPOSIT AND/OR THE APRIL 20 DEPOSIT
     ALREADY RELEASED TO SELLER AS LIQUIDATED DAMAGES AND BUYER SHALL NOT BE
     ENTITLED TO RECOVER ANY OF ITS DUE DILIGENCE EXPENSES PURSUANT TO ARTICLE 4
     ABOVE. THE PARTIES ACKNOWLEDGE THAT THE PAYMENT OF SUCH LIQUIDATED DAMAGES
     IS NOT INTENDED AS A FORFEITURE OR PENALTY WITHIN THE MEANING OF CALIFORNIA
     CIVIL CODE SECTION 3275 OR 3369, BUT IS INTENDED TO CONSTITUTE LIQUIDATED
     DAMAGES TO SELLER PURSUANT TO CALIFORNIA CIVIL CODE SECTIONS 1671, 1676,
     AND 1677. THE PARTIES HAVE SET FORTH THEIR INITIALS BELOW TO INDICATE THEIR
     AGREEMENT WITH THE LIQUIDATED DAMAGES PROVISION CONTAINED IN THIS SECTION.
     SELLER WAIVES ALL OTHER REMEDIES AGAINST BUYER FOR BUYER'S FAILURE TO CLOSE
     ESCROW, INCLUDING ANY RIGHT TO SPECIFIC PERFORMANCE UNDER CALIFORNIA CIVIL
     CODE SECTION 1680 OR ANY OTHER APPLICABLE LAW.

     BUYER AND SELLER ACKNOWLEDGE THAT THEY HAVE READ AND UNDERSTOOD THE
     PROVISIONS OF THIS SECTION 6.2 AND BY THEIR INITIALS BELOW AGREE TO BE
     BOUND BY ITS TERMS

               ________________

               Buyer's Initials         Seller's Initials

          H.   The date by which Buyer and Seller shall negotiate in reasonable
good faith to finalize the remaining provisions of Exhibits E, G, K, L, M, M-I,
Q, Y and CC and attach them to the Purchase Agreement shall be further extended
to April 20, 2000. During the time between the date hereof and April 20, 2000,
the Parties shall diligently use reasonable good faith to finalize such
Exhibits.  In the event that all of such Exhibits are not so agreed upon by such
date, then either Buyer or Seller may terminate the Purchase Agreement, in which
event the provisions of Section 4.7 thereto shall apply except that any portion
of the Deposit and the April 20 Deposit theretofore released to Seller shall not
be refunded to Buyer.

          I.   Section 4.9 of the Purchase Agreement is hereby amended by
extending the date by which Buyer and Seller shall negotiate in good faith to
finalize the IT Contract and performance bond therefor or each of the Insurance
Policies so that they are acceptable to Seller to April 20, 2000. In the

                                       5
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event that all of such Insurance Policies, the IT Contract and the performance
bond therefor are not so agreed upon by such date, then either Buyer or Seller
may terminate the Purchase Agreement, in which event the provisions of Section
4.7 thereto shall apply except that any portion of the Deposit and the April 20
Deposit theretofore released to Seller shall not be refundable to Buyer.

     2.   Seller's Right to Contact Other Parties.  If this Agreement is
          ---------------------------------------
terminated or Buyer fails to close Escrow as provided herein, then Seller may
contact directly any party, including Catellus Development Corporation,
regarding the sale of the former Kaiser Steel Mill site. Buyer, LandBank and
Hooper Knowlton and each of their affiliates have no agreement in effect and
will not place one into effect nor consent to any permitted assignee's placing
one into effect that would restrict or limit any person or entity from dealing
with Seller or the Real Property or which would require that any party who
enters into an agreement regarding the Property after such termination or
failure to close be required to pay to any of such parties any commission or
other amount.  Seller acknowledges that Buyer may enter into an agreement with
Catellus Development Corporation or any other party pursuant to which such party
will reimburse its expenses whether or not Buyer consummates the purchase of the
Real Property.

     3.   Seller's Right to Contact Catellus. In addition to Seller's having the
          ----------------------------------
right to discuss the contemplated purchase of the former Kaiser Steel Mill site
with Buyer and its members and agents, Seller may respond to or initiate
contacts with and have conversations with Catellus Development Corporation or
its employees or agents and upon notice (which may be oral), Seller may meet in
person with Catellus Development Corporation or any other person or entity
identified by Buyer as a potential financial partner. Buyer shall have the right
to attend any such meetings.

     4.   IT Reports.  Buyer shall promptly deliver to Seller (i) the IT Phase I
          ----------
report and (ii) the underwriting report for the Property which IT is preparing.

     5.   No Other Amendments.  Except as expressly amended hereby, the Purchase
          -------------------
Agreement and the Side Letter Agreement are unchanged and in full force and
effect.

     6.   Counterparts.  This Amendment may be executed in counterparts, each of
          ------------
which shall be an original and all of which taken together shall constitute the
same instrument.


                      [Signatures continued on next page]

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<PAGE>

          IN WITNESS WHEREOF, the parties hereto have executed this Amendment as
of the dates written below.


Buyer:                     ONTARIO VENTURES I, LLC, a Delaware limited liability
-----
                              company

                              By:  LandBank Environmental Properties, LLC, a
                                   Delaware limited liability company, its
                                   Manager

                                   By:  LandBank, Inc., a Delaware corporation,
                                        its managing member


                                        By:  /s/ Stuart L. Miner
                                             -----------------------------------
Date Executed: 03/14/00                 Its:  Vice President
               --------                      -----------------------------------


Seller:                       KAISER VENTURES INC., a Delaware corporation
------


                              By: /s/ Terry L. Cook
                                  ----------------------------------------------
Date Executed: 03/14/00       Its:  Executive Vice President  & General Counsel
               --------            ---------------------------------------------


                              KAISER STEEL LAND DEVELOPMENT INC., a Delaware
                              corporation


                              By: /s/ Terry L. Cook
                                  ----------------------------------------------
Date Executed: 03/14/00       Its:  Vice President
               --------           ----------------------------------------------

                                       7
<PAGE>

RECEIVED AND ACCEPTED THIS ____ DAY OF _______________, 2000.


ESCROW HOLDER:



CHICAGO TITLE INSURANCE COMPANY


By:________________________

Its:_______________________


          The undersigned hereby acknowledge that they agree to be bound by the
provisions of paragraph 2 above.

                              LandBank Environmental Properties, LLC, a Delaware
                              limited liability company, its Manager

                              By:  LandBank, Inc., a Delaware corporation, its
                                   managing member


                                   By:  /s/ Stuart L. Miner
                                      ------------------------------------------

Date Executed: 03/14/00            Its:  Vice President
               --------                -----------------------------------------


Date Executed: 03/14/00            /s/ Hooper Knowlton
               --------            ---------------------------------------------
                                   Hooper Knowlton

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