EXHIBIT 10.7.4

FIFTH AMENDMENT TO LEASE AGREEMENT

GRE EMPIRE TOWERS LP,

a Delaware limited partnership

(“LANDLORD”)

AND

KAISER VENTURES, LLC,

a Delaware limited liability company,

p/k/a Kaiser Resources, Inc.

(“TENANT”)

This Fifth Amendment to Lease Agreement (“Fifth Amendment”), is made as of
March 16, 2009, by and between GRE EMPIRE TOWERS LP, a Delaware limited
partnership (“Landlord”), and KAISER VENTURES, LLC, a Delaware limited liability
company, p/k/a Kaiser Resources, Inc.(“Tenant”).

RECITALS

A. Landlord is the Owner of Empire Towers I located at 3633 E. Inland Empire
Boulevard, Ontario, California (“Building”) and is the successor Landlord to
Empire Towers I LLC, a California limited liability company, which was the
successor Landlord to Lord Baltimore Capital Corporation previously known as
American Trading Real Estate Properties, Inc. under that certain Lease Agreement
and Addendum thereto dated June 6, 1994 (“Original Lease”), amended by a First
Amendment to Lease Agreement dated May 18, 1999 (“First Amendment”), a Second
Amendment to Lease Agreement dated September 27, 1999 (“Second Amendment”), a
Third Amendment to Lease Agreement dated February 19, 2002 (“Third Amendment”),
and a Fourth Amendment to Lease Agreement dated November 13, 2006 (“Fourth
Amendment”) (collectively referred to as “Lease Agreement”), for Suite 480
comprising approximately three thousand one hundred twenty-eight (3,128) gross
rentable square feet (“Premises”). Tenant is the Tenant under the Lease
Agreement.

B. Landlord and Tenant desire to further amend the Lease Agreement on the terms
and conditions provided below.

AGREEMENTS

NOW, THEREFORE, in consideration of the mutual covenants contained herein and
other good and valuable consideration, the receipt and sufficiency of which is
hereby acknowledged, the parties agree as follows:

1. Incorporation of Recitals. All of the recitals set forth above are hereby
made an integral part of this Fifth Amendment.

2. Definitions. All capitalized terms not otherwise defined in this Fifth
Amendment herein shall have the meaning ascribed to them in the Lease Agreement.

3. Term. Notwithstanding any provision to the contrary contained in the Lease

 

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Agreement, including, without limitation, Section 3.01 of the Original Lease,
Section 3 of the First Amendment, Section 3 of the Third Amendment, and
Section 3 of the Fourth Amendment, the term of the Lease Agreement for the
Premises is hereby extended for a period of twenty-four (24) months commencing
September 1, 2009 and expiring August 31, 2011 (“Fourth Extended Term”).

4. Base Rent for the Premises. The monthly Base Rent for the Demised Premises
during the Fourth Extended Term shall be as follows:

 

MONTHS

   RATE PER SQ. FT.
PER MONTH    MONTHLY BASE RENT

9/1/09 - 8/31/10

   $ 2.05    $ 6,412.40

9/1/10 - 8/31/11

   $ 2.11    $ 6,600.08

Notwithstanding anything to the contrary set forth in the Lease Agreement, Base
Rent during the period from June 1, 2009, through August 31, 2009, shall be
abated in its entirety.

5. Base Taxes. As of September 1, 2009, Base Taxes for the Demised Premises
shall mean Taxes for the calendar year 2009.

6. Base Operating Costs. As of September 1, 2009, Base Operating Costs for the
Demised Premises shall mean Operating Costs for the calendar year 2009.

7. Tenant Improvements. On or before September 30, 2009, Landlord shall, at
Landlord’s sole cost and expense (i) professionally clean the existing carpeting
in the Demised Premises, and (ii) paint the Demised Premises utilizing Building
Standard paint. Other than the foregoing, Landlord shall have no obligation to
prepare the Demised Premises for Tenant’s continued occupancy during the Fourth
Extended Term.

8. Option to Extend Term. All options to extend the term of the Lease Agreement,
if any, set forth in the Lease Agreement are hereby deleted in their entirety,
including, without limitation, Article 43 of the First Amendment and Section 8
of the Fourth Amendment, and are replaced by the Option to Extend the Term
described in this Section 8 of this Fifth Amendment. Provided Tenant has cured
any default of the Lease Agreement in the prescribed time and manner described
in the Lease Agreement at any time from the time Tenant exercises the applicable
option as set forth herein until such time as such extended term commences,
Tenant shall have two (2) options to extend the term (each an “Option to Extend
the Term”) of this Lease Agreement for an additional period of twelve
(12) months each (each an “Additional Extended Term”) immediately following the
expiration date of the Fourth Extended Term and the first Additional Extended
Term, as applicable. To exercise each option, Tenant must give written notice to
Landlord at least six (6) months, but not more than nine (9) months, prior to
the expiration date of the Fourth Extended Term or the first Additional Extended
Term, as applicable. Time is agreed to be of the essence with respect to this
notice requirement.

In the event Tenant effectively exercises each such option, the annual base rent
(“Annual

 

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Base Rent”) for the Demised Premises over the applicable Additional Extended
Term shall be the then fair market rental rate per rentable square foot of the
Demised Premises per annum as determined by Landlord. Landlord shall advise
Tenant in writing of the then fair market rental rate for the Demised Premises.
As used herein, “fair market rental rate” shall mean the annual rate per
rentable square foot that Landlord could reasonably expect to obtain from a
third party desiring to lease the Demised Premises within the Ontario Airport
submarket for the applicable Additional Extended Term, taking into account all
allowances, concessions and commissions. If Tenant accepts Landlord’s statement
of such fair market rental rate in writing within thirty (30) days of receipt of
Landlord’s statement of the same, the Base Taxes and Base Operating Costs during
the applicable Additional Extended Term shall be the actual Taxes and Operating
Costs for calendar year two thousand nine (2010) for the first Additional
Extended Term, and for calendar year two thousand eleven (2011) for the second
Additional Extended Term. If Tenant objects to the fair market rental rate
submitted by Landlord within such thirty day period, Landlord and Tenant will
attempt in good faith to agree upon such fair market rental rate using their
best good faith efforts. If Landlord and Tenant fail to reach agreement on such
fair market rental rate within fifteen (15) days thereafter, then either
Landlord or Tenant may terminate the applicable Option to Extend the Term upon
written notice to the other party.

Each Option to Extend the Term may only be exercised as to the entire Demised
Premises and any attempt to exercise an Option to Extend the Term as to any
portion of the Demised Premises, but not as to the entire Demised Premises,
shall be null and void. The second Option to Extend the Term shall be null and
void unless Tenant has validly exercised the first Option to Extend the Term.

Each Option to Extend the Term shall be personal to the original Tenant
hereunder named Kaiser Venture, LLC and shall be immediately null and void and
of no effect if such original Tenant assigns the Lease Agreement with or without
Landlord’s consent in accordance with Article VI of the Lease Agreement.

Except as otherwise provided in this Article, all of the covenants, terms and
conditions of this Lease Agreement shall apply in full force and effect during
each Additional Extended Term except that (i) any financial incentives; (ii) any
construction work; (iii) any options to reduce, extend, expand, terminate; and
(iv) any rights of first refusal, offer or negotiation previously provided to
Tenant shall not be applicable to each Additional Extended Term.

Prior to the first day of each Additional Extended Term, Landlord shall prepare
and Landlord and Tenant shall execute an amendment to the Lease Agreement for
the purpose of confirming the above.

9. No Brokers. Landlord and Tenant acknowledge that CIP Real Estate Property
Services (the “Landlord’s Broker”) represented Landlord in this transaction and
Tenant was not represented by a broker. Landlord and Tenant each represent and
warrant to each other that it has not had any dealing with any other real estate
broker or finder with respect to this First Amendment and agree to hold each
other harmless from and against any and all damages, costs, expenses resulting
from any claim(s) for a brokerage commission or finder’s fee that may be
asserted against either of them by any broker or finder with whom the other has
dealt or with whom such other broker or finder claims to have dealt with.

 

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10. No Defaults. To Tenant’s actual knowledge, (i) there are no defaults of
Landlord or Tenant under the Lease Agreement or any existing conditions, which
upon giving notice or lapse of time or both would constitute a default under the
Lease Agreement and (ii) there are no offsets or credits against the payment of
rent due under the Lease Agreement.

11. Authority. Each party hereto warrants that the person signing below on such
party’s behalf is authorized to do so and to bond such party to the terms of
this Fifth Amendment.

12. Effective of Fifth Amendment, Affirmation of Lease Agreement. Except for any
financial incentives or construction work previously provided Tenant and except
as specifically amended and modified by this Fifth Amendment, the Lease
Agreement is hereby affirmed and remains in full force and effect. In the event
of any conflict between the terms of this Fifth Amendment and the Lease
Agreement, the terms and conditions of this Fifth Amendment shall prevail.

IN WITNESS WHEREOF, the parties hereto have executed this Fifth Amendment on the
date set forth opposite their respective signatures below.

 

LANDLORD: GRE EMPIRE TOWERS LP, a Delaware limited partnership By:   CIP Real
Estate,   a California corporation   Its Investment Manager   By:   /s/ Katie
McKenna     Katie McKenna     Authorized Signatory TENANT: KAISER VENTURES, LLC,
a Delaware limited liability company By:   /s/ Terry L. Cook   Name:   Terry L.
Cook   Its:   Exec. V.P. & General Counsel

 

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