SQLLoader and compensating for incorrect date values

I am using SQLLDR to load data from a fixed length file using this ctl file:
LOAD DATA

• INFILE D:\jul1501.txt INSERT INTO TABLE CR51.CR_PEOPLE TRAILING NULLCOLS ( CR_ID DECIMAL EXTERNAL "CR51.CR_PEOPLE_ID_S.NEXTVAL", FILE_ID position (1:9) char, LAST_NAME position (10:24) char, FIRST_NAME position (25:33) char, MI position (34:34) char, ADDRESS position (35:54) char, CITY position (55:69) char, BIRTH_DATE position (70:74) DATE "MMDDYYYY" NULLIF (BIRTH_DATE = "not a valid month"), CREATION_DATE SYSDATE )

772660018SMITH SUSAN 691 N ROVER ROAD SAN JOSE 06311952 There is no 6/31/1952
772660018SMITH GEOFF 691 N ROVER ROAD SAN JOSE 1952 The data is invalid, year only
772660018SMITH SUSAN 691 N ROVER ROAD SAN JOSE It's completely missing

I would prefer to just load these columns as null, but I'm not finding the correct syntax.

Any comments or suggestions?

I'd prefer not to edit the bad file - there are too many records.

--
Dick
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