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OMB NUMBER 3235-0145
Expires: October 31, 1994
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 4 )*
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Tetra Tech, Inc.
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(Name of Issuer)
COMMON STOCK, $0.01 par value
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(Title of Class of Securities)
881 62G 103
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(CUSIP Number)
Check the following box if a fee is being paid with the statement [_]. (A fee
is not required only if the reporting person: (1) has a previous statement on
file reporting beneficial ownership of more than five percent of the class of
securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such class.)
(See Rule 13d-7.)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.
The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
Page 1 of 5
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SCHEDULE 13G
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CUSIP NO. 881 62G 103 PAGE 2 OF 5 PAGES
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NAME OF REPORTING PERSON
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Li-San Hwang
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CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [_]
(b) [_]
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SEC USE ONLY
3
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CITIZENSHIP OR PLACE OF ORGANIZATION
4
United States
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SOLE VOTING POWER
5
NUMBER OF 1,121,757
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
-0-
OWNED BY
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EACH SOLE DISPOSITIVE POWER
7
REPORTING 1,121,757
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
-0-
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
1,121,757
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CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
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PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11
7.9%
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TYPE OF REPORTING PERSON*
12
IN
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*SEE INSTRUCTION BEFORE FILLING OUT!
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SCHEDULE 13G
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CUSIP NO. 881 62G 103 PAGE 3 OF 5 PAGES
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ITEM 1.
(a) NAME OF ISSUER
Tetra Tech, Inc.
(b) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES
670 North Rosemead Boulevard
Pasadena, California 91107
ITEM 2.
(a) NAME OF PERSON FILING
Li-San Hwang
(b) ADDRESS OF PRINCIPAL OFFICE
670 North Rosemead Boulevard
Pasadena, California 91107
(c) CITIZENSHIP
United States of America
(d) TITLE OF CLASS OF SECURITIES
Common Stock, $.01 par value
(e) CUSIP NUMBER
881 62G 103
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULES 13d-1(b), OR 13d-
2(b), CHECK WHETHER THE PERSON FILING IS A:
Not Applicable
ITEM 4. OWNERSHIP
(a) AMOUNT BENEFICIALLY OWNED:
1,121,757
(b) PERCENT OF CLASS:
7.9%
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SCHEDULE 13G
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CUSIP NO. 881 62G 103 PAGE 4 OF 5 PAGES
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(c) NUMBER OF SHARES AS TO WHICH SUCH PERSON HAS:
(i) SOLE POWER TO VOTE OR TO DIRECT THE VOTE: 1,121,757
(ii) SHARED POWER TO VOTE OR TO DIRECT THE VOTE: -0-
(iii) SOLE POWER TO DISPOSE OR TO DIRECT THE DISPOSITION OF:
1,121,757
(iv) SHARED POWER TO DISPOSE OR TO DIRECT THE DISPOSITION OF: -0-
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
Not Applicable.
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
Not Applicable.
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH
ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING
COMPANY
Not Applicable.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
Not Applicable.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP
Not Applicable.
ITEM 10. CERTIFICATION
Not Applicable.
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SCHEDULE 13G
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CUSIP NO. 881 62G 103 PAGE 5 OF 5 PAGES
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SIGNATURES
AFTER REASONABLE INQUIRY AND TO THE BEST OF MY KNOWLEDGE AND BELIEF, I
CERTIFY THAT THE INFORMATION SET FORTH IN THIS STATEMENT IS TRUE, COMPLETE AND
CORRECT.
/s/ Li-San Hwang
_________________________________________
LI-SAN HWANG
DATE: FEBRUARY 7, 1997
