SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549



                                    FORM 8-K/A
                                 AMENDMENT NO. 1



                             Current Report Pursuant
                          to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934



    Date of report (Date of earliest event reported)        September 27, 2002
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                               UNOCAL CORPORATION
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             (Exact name of registrant as specified in its charter)



                                    Delaware
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                 (State or Other Jurisdiction of Incorporation)



    1-8483                                   95-3825062
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(Commission File Number)                (I.R.S. Employer Identification No.)



2141 Rosecrans Avenue, Suite 4000, El Segundo, California         90245
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(Address of Principal Executive Offices)                       (Zip Code)



                                 (310) 726-7600
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              (Registrant's Telephone Number, Including Area Code)



Item 5.      Other Events.

This Current Report on Form 8-K/A amends the original report filed on September
27, 2002, to include further clarification regarding the provision for
environmental remediation which the Company expects to include in its third
quarter 2002 consolidated earnings statement.

Provision for Environmental Remediation

Unocal Corporation (the "Company") anticipates that its third quarter 2002
reported net earnings will include a provision of approximately $35 million
pretax ($22 million after tax), or 9 cents per share (diluted), for additional
reserves for environmental remediation. The anticipated provision resulted from
the Company's regular quarterly review of remediation obligations.

The anticipated provision reflects an $18 million increase in remediation cost
estimates for sites included in the Company's "Inactive or closed Company
facilities" category. This additional amount is principally for the
decommissioning and decontamination of closed molybdenum and rare earth
processing facilities in Washington and York, Pennsylvania, of the Company's
Molycorp, Inc. subsidiary. As a result of ongoing cooperative efforts between
the Company and the Nuclear Regulatory Commission, it was determined that it was
probable that additional volumes of low-level radioactive contaminated material,
in excess of amounts previously estimated, need to be removed at the York and
Washington sites.

The anticipated provision also reflects an $11 million increase in cost
estimates for sites included in the "Company facilities sold with retained
liabilities and former Company-operated sites" category. The anticipated
provision for these sites reflects primarily revised remediation cost estimates
that the Company has received from the purchaser of service stations, bulk
plants, terminals, refineries and pipelines that were part of the Company's
"downstream" business sold in 1997. In addition, the provision includes
increases for approximately 50 other sites in this category.

The remaining $6 million of the provision relates to six sites in the "Active
Company facilities" and Superfund and similar sites" categories of reported
remediation costs.

Most of the $35 million was included in the Company's reported June 30, 2002
estimate of possible additional remediation costs.

This provision was not considered in the Company's earlier estimate of third
quarter 2002 reported net earnings in the upper end of the 45 to 55 cents per
share (diluted) range, included in its Current Report on Form 8-K dated
September 4, 2002. The Company now expects reported net earnings per share
(diluted) to be in the upper end of a range of 35 to 45 cents for the third
quarter 2002. The full-year expected range of reported net earnings remains
unchanged at $1.60 to $1.80 per share (diluted).

Forward-looking statements and estimates regarding projected provisions for
environmental reserves in this filing are based on assumptions about
engineering, operational, regulatory, environmental, political and other
considerations. Such forward looking statements as well as those regarding
expected earnings are based on the Company's current expectations and beliefs
and are subject to a number of unknown risks and uncertainties that could cause
actual results to differ materially from those described in the forward looking
statements. Actual results could differ materially as a result of factors
discussed in the Company 's amended 2001 Annual Report on Form 10-K/A and
subsequent reports filed with the Securities and Exchange Commission.

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Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.




                                           UNOCAL CORPORATION
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                                           (Registrant)




Date:  October 11, 2002                  By:/s/ JOE D. CECIL
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                                           Joe D. Cecil
                                           Vice President and Comptroller

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