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                          FIRST AMENDMENT TO GUARANTY           EXHIBIT 10.29.3
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     This Amendment, dated as of January 30, 1997, is entered into by KAISER
VENTURES INC., a Delaware corporation (formerly known as "Kaiser Resources
Inc.") (the "Guarantor"), and UNION BANK OF CALIFORNIA, N.A., a national banking
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association (successor in interest to Union Bank, a California banking
corporation) (the "Bank").
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                                   Recitals
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     A.   The Guarantor has executed a Guaranty dated as of September 30, 1994
(the "Guaranty") in favor of the Bank, pursuant to which the Guarantor has
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guaranteed all of the obligations of Fontana Water Resources, Inc., a Delaware
corporation (the "Borrower"), to the Bank under the Revolving Credit and Term
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Loan Agreement dated as of September 30, 1994 (the "Credit Agreement") between
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the Borrower and the Bank.  Terms defined in the Credit Agreement and not
otherwise defined herein have the same respective meanings when used herein, and
the rules of interpretation set forth in Sections 1.2 and 1.3 of the Credit
Agreement are incorporated herein by reference.

     B.   The Guarantor and the Bank wish to amend the Guaranty to revise
certain of the waivers contained therein.  Accordingly, the Guarantor and the
Bank agree as set forth below.


1.  Amendments to Guaranty.  The Guaranty is hereby amended as set forth below.
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          (a) Section 4(b) of the Guaranty is amended in full to read as
follows:

          "(b)  Without limiting the generality of any other provision of this
     Guaranty, the Guarantor waives all rights and defenses that it may have
     because the Borrower's debt is secured by real property.  This means, among
     other things, that:
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                "(i)  the Bank may collect from the Guarantor without first
     foreclosing on any real- or personal-property collateral pledged by the
     Borrower; and

                "(ii)  if the Bank forecloses on any real property collateral
     pledged by the Borrower:

                       "(A)  the amount of the debt may be reduced only by the
     price for which that collateral is sold at the foreclosure sale, even if
the collateral is worth more than the sale price; and

                       "(B)  the Bank may collect from the Guarantor even if the
     Bank, by foreclosing on the real-property collateral, has destroyed any
     right that the Guarantor may have to collect from the Borrower.

     "This is an unconditional and irrevocable waiver of any rights and defenses
     that the Guarantor may have because the Borrower's debt is secured by real
     property.  These rights and defenses include, but are not limited to, any
     rights or defenses based upon Section 580a, 580b, 580d or 726 of the
     California Code of Civil Procedure."

          (b) Section 4 of the Guaranty is amended by adding a new Section 4(c),
to read as follows:

          "(c)  Without limiting the generality of any other provision of this
     Guaranty, the Guarantor waives all rights and defenses arising out of an
     election of remedies by the Bank, even though that election of remedies,
     such as a nonjudicial foreclosure with respect to security for a guaranteed
     obligation, has destroyed the Guarantor's rights of subrogation and
     reimbursement against the Borrower by the operation of Section 580d of the
     California Code of Civil Procedure or otherwise."

2.  Representations and Warranties of Guarantor.  The Guarantor represents and
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warrants to  the Bank as set forth below.

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          (a) The execution, delivery and performance by the Guarantor of this
Amendment, and of the Guaranty as amended hereby, and the consummation of the
transactions contemplated by this Amendment and the Guaranty as amended hereby,
are within the Guarantor's corporate powers, have been duly authorized by all
necessary corporate action and do not (i) contravene the Guarantor's charter
documents or bylaws, (ii) violate any Governmental Rule, (iii) conflict with or
result in the breach of, or constitute a default under, any Material Contract,
loan agreement, indenture, mortgage, deed of trust or lease, or any other
contract or instrument binding on or affecting the Guarantor or any of its
properties, the conflict, breach or default of which would be reasonably likely
to have a materially adverse effect on the business, condition (financial or
other wise), operations, performance, properties or prospects of the Guarantor
or the ability of the Guarantor to perform its obligations under any of the
Credit Documents, as amended by this Amendment, or (iv) result in or require the
creation or imposition of any Lien upon or with respect to any of the properties
of the Guarantor, other than in favor of the Bank.

          (b) No Governmental Action is required for the due execution, delivery
or performance by the Guarantor of this Amendment, or of the Guaranty as amended
hereby.

          (c) This Amendment, and the Guaranty as amended hereby, constitute
legal, valid and binding obligations of the Guarantor, enforceable against the
Guarantor in accordance with their respective terms, except as the
enforceability thereof may be limited by bankruptcy, insolvency, moratorium,
reorganization or other similar laws affecting creditors' rights generally.

          (d) The Stock Pledge Agreement constitutes a valid and perfected
first-priority Lien on the Collateral purported to be covered thereby,
enforceable against all third parties in all jurisdictions, and secures the
payment of all obligations of the Guarantor under the Guaranty, as amended by
this Amendment, and the other Credit Documents; and the execution, delivery and
performance of this Amendment do not adversely affect the Lien of the Stock
Pledge Agreement.

          (e) The audited consolidated balance sheet of the Guarantor and its
Subsidiaries as of December 31, 1995, and the

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related audited consolidated statements of income, retained earnings and cash
flows of the Guarantor and its Subsidiaries for the fiscal year then ended,
fairly present the consolidated financial condition of the Guarantor and its
Subsidiaries as of such date and the consolidated results of the operations of
the Guarantor and its Subsidiaries for the fiscal year ended on such date, all
in accordance with generally accepted accounting principles applied on a
consistent basis. The unaudited consolidated balance sheet of the Guarantor and
its Subsidiaries as of [September] 30, 1996, and the related unaudited
consolidated statements of income, retained earnings and cash flows of the
Guarantor and its Subsidiaries for the [9]-month period then ended, certified
(subject to normal year-end audit adjustments) by the chief financial officer or
chief accounting officer of the Guarantor as having been prepared in accordance
with generally accepted accounting principles applied on a consistent basis,
fairly present the consolidated financial condition of the Guarantor and its
Subsidiaries as of such date and the consolidated results of the operations of
the Guarantor and its Subsidiaries for the [9]-month period ended on such date.
Since [September] 30, 1996 there has been no materially adverse change in the
business, condition (financial or otherwise), operations, performance,
properties or prospects of the Guarantor or any of its Subsidiaries. The
Guarantor and its Subsidiaries have no material contingent liabilities, except
as disclosed in such consolidated financial statements or the notes thereto,
that would be reasonably likely to have a materially adverse effect on the
business, condition (financial or otherwise), operations, performance,
properties or prospects of the Guarantor or any of its Subsidiaries.

          (f) There is no pending or, to the knowledge of the Guarantor,
threatened action, suit, investigation, litigation or proceeding affecting the
Guarantor before any Governmental Person or arbitrator that purports to affect
the legality, validity or enforceability of this Amendment or of the Guaranty as
amended hereby.

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3.  Reference to and Effect on Guaranty.
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          (a) On and after the effective date of this Amendment, each reference
in the Guaranty to "this Guaranty," "hereunder," "hereof," "herein" or any other
expression of like import referring to the Guaranty, and each reference in the
other Credit Documents to "the Guaranty," "thereunder," "thereof," "therein" or
any other expression of like import referring to the Guaranty, shall mean and be
a reference to the Guaranty as amended by this Amendment.

          (b) Except as specifically amended by this Amendment, the Guaranty
shall remain in full force and effect and is hereby ratified and confirmed.
Without limiting the generality of the foregoing, the Stock Pledge Agreement and
all of the Collateral described therein do and shall continue to secure the
payment of all obligations of the Guarantor under the Guaranty, as amended by
this Amendment, and the other Credit Documents.

          (c) The execution, delivery and effectiveness of this Amendment shall
not operate as a waiver of any right, power or remedy of the Bank under any of
the Credit Documents or constitute a waiver of any provision of any of the
Credit Documents.

4.  Consent.  The Guarantor hereby consents to the First Amendment to Revolving
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Credit and Term Loan Agreement dated as of January 30, 1997 (the "Credit
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Agreement Amendment") between the Borrower and the Bank and hereby confirms and
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agrees that the Guaranty is and shall continue to be in full force and effect
and is ratified and confirmed in all respects, except that, on and after the
effective date of the Credit Agreement Amendment, each reference in the Guaranty
to "the Credit Agreement," "thereunder," "thereof," "therein" or any other
expression of like import referring to the Credit Agreement shall mean and be a
reference to the Credit Agreement as amended by the Credit Agreement Amendment.

5.  Costs and Expenses.  The Guarantor agrees to pay on demand all costs and
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expenses of the Bank in connection with the preparation, execution and delivery
of this Amendment and the other instruments and documents to be delivered
hereunder,

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including the reasonable fees and out-of-pocket expenses of legal counsel for
the Bank with respect thereto and with respect to advising the Bank as to its
rights and responsibilities hereunder and thereunder.

6.  Headings.  The section headings used herein have been inserted for
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convenience of reference only and do not constitute matters to be considered in
interpreting this Amendment.

7.  Execution in Counterparts.  This Amendment may be executed in any number of
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counterparts and by the parties hereto in separate counterparts, each of which
when so executed and delivered shall be deemed to be an original and all of
which taken together shall constitute one and the same instrument.

8.  Governing Law.  THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
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ACCORDANCE WITH, THE LAWS OF THE STATE OF CALIFORNIA APPLICABLE TO CONTRACTS
MADE AND PERFORMED IN THE STATE OF CALIFORNIA.


                                           KAISER VENTURES INC.


                                           By: /s/ James F. Verhey
                                                _________________________
                                                James F. Verhey
                                                Vice President &
                                                  Chief Financial Officer



                                           UNION BANK OF CALIFORNIA, N.A.


                                           By: /s/ Bret A. Martin
                                               _________________________
                                           Name: Bret A. Martin
                                                 _______________________
                                           Title: Vice President
                                                  ______________________

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