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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 5 )*
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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)
*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 the disclosures provided in a prior page.
The information required in 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).
(Continued on following page(s))
Page 1 of 4 Pages
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CUSIP No. 881 62G 103 13G Page 2 of 4 Pages
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(1) Names of Reporting Persons. S.S. or I.R.S. Identification Nos. of Above
Persons
Li-San Hwang
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(2) Check the Appropriate Box if a Member (a) / /
of a Group* (b) / /
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(3) SEC Use Only
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(4) Citizenship or Place of Organization
United States
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Number of Shares (5) Sole Voting
Beneficially Power 1,405,153
Owned by --------------------------------------------------
Each Reporting (6) Shared Voting
Person With Power -0-
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(7) Sole Dispositive
Power 1,405,153
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(8) Shared Dispositive
Power -0-
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(9) Aggregate Amount Beneficially Owned by Each Reporting Person
1,405,153
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(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
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(11) Percent of Class Represented by Amount in Row (9)
6.3%
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(12) Type of Reporting Person*
IN
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*SEE INSTRUCTION BEFORE FILLING OUT!
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Page 3 of 4 Pages
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ITEM 1(A). NAME OF ISSUER
Tetra Tech, Inc.
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ITEM 1(B). ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES
670 North Rosemead Boulevard, Pasadena, California 91107
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ITEM 2(A). NAME OF PERSON(S) FILING
Li-San Hwang
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ITEM 2(B). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE
670 North Rosemead Boulevard, Pasadena, California 91107
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ITEM 2(C). CITIZENSHIP
United States of America
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ITEM 2(D). TITLE OF CLASS OF SECURITIES
Common Stock, $.01 par value
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ITEM 2(E). CUSIP NUMBER
881 62G 103
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ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B), OR 13D-2(B),
CHECK WHETHER THE PERSON FILING IS A
(a) / / Broker or Dealer registered under Section 15 of the Act
(b) / / Bank as defined in section 3(a)(6) of the Act
(c) / / Insurance Company as defined in section 3(a)(19) of the Act
(d) / / Investment Company registered under section 8 of the Investment
Company Act
(e) / / Investment Adviser registered under section 203 of the Investment
Advisers Act of 1940
(f) / / Employee Benefit Plan, Pension Fund which is subject to the
provisions of the Employee Retirement Income Security Act of 1974
or Endowment Fund; see Rule 13d-1(b)(1)(ii)(F)
(g) / / Parent Holding Company, in accordance with Rule 13d-1(b)(ii)(G)
(Note: See Item 7)
(h) / / Group, in accordance with Rule 13d-1(b)(1)(ii)(H)
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Page 4 of 4 Pages
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ITEM 4. OWNERSHIP
(a) Amount Beneficially Owned:
1,405,153
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(b) Percent of Class:
6.3%
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(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote
1,405,153
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(ii) shared power to vote or to direct the vote
-0-
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(iii) sole power to dispose or to direct the disposition of
1,405,153
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(iv) shared power to dispose or to direct the disposition of
-0-
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ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
If this statement is being filed to report the fact that as of the date hereof
the reporting person has ceased to be the beneficial owner of more than five
percent of the class of securities, check the following. / /
Not Applicable
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
Not Applicable
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ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
Not Applicable
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ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
Not Applicable
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ITEM 9. NOTICE OF DISSOLUTION OF GROUP
Not Applicable
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ITEM 10. CERTIFICATION
By signing below I certify that, to the best of my knowledge and belief,
the securities referred to above were acquired in the ordinary course of
business and were not acquired for the purpose of and do not have the effect of
changing or influencing the control of the issuer of such securities and were
not acquired in connection with or as a participant in any transaction having
such purposes or effect.
SIGNATURE
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.
February 10, 1998
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(Date)
/s/ Li-San Hwang
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(Signature)
Li-San Hwang
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(Name/Title)
