TETRA TECH INC
MATERIAL CONTRACTS
<DOCUMENT>
<TYPE>EX-10.22
<SEQUENCE>6
<FILENAME>a05-21654_1ex10d22.htm
<DESCRIPTION>MATERIAL CONTRACTS
<TEXT>
<html>

<head>





</head>

<body lang="EN-US">

<div style="font-family:Times New Roman;">

<p align="right" style="margin:0in 0in .0001pt;text-align:right;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Exhibit&nbsp;10.22</font></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><u><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">TETRA TECH, INC.</font></u></b></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><u><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">RESTRICTED STOCK UNIT AWARD</font></u></b></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Name of Participant:</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">This Restricted Stock Unit (&#147;RSU&#148;) Award </font></b>made this &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
(&#147;Grant Date&#148;), by Tetra Tech,&nbsp;Inc. (the &#147;Company&#148;) to<b><font style="font-weight:bold;"> </font></b>Participant
is evidence of an Award made under the Company&#146;s 2005 Equity Incentive Plan (the
&#147;Plan&#148;).&#160; The Plan is incorporated into
this Award by reference.</p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">1.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Number
of RSUs</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Subject to the restrictions, limitations, terms and
conditions specified in the Plan and this Award, the Company hereby awards to
the Participant as of the Grant Date &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
RSUs.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">All fractional RSUs resulting from the adjustment
provisions contained in the Plan shall be rounded down to the nearest whole
unit.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">2.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Vesting
Schedule</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">If the Participant remains employed with the Company
or a Subsidiary through each Vesting Date, &nbsp;&nbsp;&nbsp;&nbsp;% of the
RSUs shall vest on each anniversary of the Grant Date.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">RSUs will remain restricted until each Vesting Date
noted above.&#160; RSUs are not transferable
by the Participant by means of sale, assignment, exchange, pledge or otherwise
prior to vesting.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">If the Participant&#146;s employment with the Company or
a Subsidiary is terminated for any reason, whether voluntarily or
involuntarily, no additional RSUs under this Award shall become vested RSUs
under any circumstances except as provided below for death or Disability.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&#147;Employment&#148; covered under this Agreement shall mean
the performance of services for the Company or a Subsidiary as an employee for
federal income tax purposes.&#160; The Participant
shall be deemed to have terminated employment either upon an actual termination
of service with the Company or a Subsidiary, or at the time that the Subsidiary
with which the Participant is employed ceases to be a Subsidiary under the
terms of the Plan, provided that the Participant is not employed immediately
thereafter by the Company.&#160; The
Participant&#146;s employment with the Company or a Subsidiary shall not be deemed
to have terminated if the Participant takes any military leave, sick leave or
other bona fide leave of absence approved by the Company or the Subsidiary, as
applicable, regardless of whether pay is suspended during such leave.</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">1</font></p>

<div style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">

<hr size="2" width="100%" noshade color="gray" align="left">

</font></div>

</div>
<!-- SEQ.=1,FOLIO='1',FILE='C:\JMS\ayusoof\05-21654-2\task704374\21654-2-ko.htm',USER='myusoof',CD='Dec 14 01:30 2005' -->


<br clear="all" style="page-break-before:always;">


<div style="font-family:Times New Roman;">

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">3.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Distribution
of Common Stock</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The Company shall issue to the Participant as soon
as practicable following the applicable Vesting Date the number of shares of
the Company&#146;s common stock equal to the number of RSUs vesting on such
date.&#160; If the Vesting Date of any portion
of the RSUs shall occur during either a regularly scheduled or special &#147;blackout
period&#148; of the Company wherein the Participant is precluded from selling shares
of the Company&#146;s common stock, the receipt of such shares issuable with respect
to such Vesting Date under this Award shall be deferred until after the
expiration of such blackout period, but in no event later than two and one half
months after the end of the end of the calendar year which includes the Vesting
Date.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">In lieu of receiving shares of the Company&#146;s common
stock in connection with vesting as described above, the Participant may elect
to defer the distribution of shares of the Company&#146;s common stock on some or
all of the RSUs in accordance with administrative rules&nbsp;as may be
established by the Committee from time to time.&#160;
An election must be received in writing by the Company no later than 30
days after the Grant Date.&#160; The
Participant will have no right to accelerate or further defer a deferred
distribution.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">4.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Dividend
Equivalents.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Subject to the restrictions, limitations and
conditions as described in the Plan, dividend equivalents payable on the RSUs
will be accrued on behalf of the Participant at the time that dividends are
otherwise paid to owners of the Company&#146;s common stock.&#160; Dividends shall earn interest at &nbsp;&nbsp;&nbsp;&nbsp;%
and shall be paid (along with such interest) on the Vesting Date for the RSUs
with respect to which such amounts were accrued under the Plan.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">5.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Taxes.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Notwithstanding any other provision in this Award to
the contrary, any distribution of shares of the Company&#146;s common stock or dividend
equivalents shall be subject to tax withholding.&#160; Taxes will be settled by withholding cash
and/or a number of shares with a Fair Market Value not less than the amount of
the minimum required tax withholding. &#160;The
Participant is personally responsible for the proper reporting and payment of
all taxes related to shares distributed with respect to RSUs and dividend equivalents.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">6.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Death
or Disability.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">If you terminate employment with the Company because
of your death or Disability, this Award will vest immediately.&#160; Accelerated vesting will not impact the time
for distributing shares of the Company&#146;s common stock to you if you previously
elected to defer distribution.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">7.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Change
of Control</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The RSUs granted under this Award that have not
vested as of immediately prior to a Change of Control shall vest as of the date
the Change of Control is finalized, provided</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2</font></p>

<div style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">

<hr size="2" width="100%" noshade color="gray" align="left">

</font></div>

</div>
<!-- SEQ.=1,FOLIO='2',FILE='C:\JMS\ayusoof\05-21654-2\task704374\21654-2-ko.htm',USER='myusoof',CD='Dec 14 01:30 2005' -->


<br clear="all" style="page-break-before:always;">


<div style="font-family:Times New Roman;">

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">that the Participant is then actively employed by
the Company.&#160; The amount of shares of the
Company&#146;s common stock corresponding to such vested RSUs shall be issued to the
Participant immediately notwithstanding any prior deferral election.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">8.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Forfeiture.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Any RSUs that are not vested as of the Participant&#146;s
termination of employment with the Company shall be immediately forfeited.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">9.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Conformity
with the Plan.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">This Award is intended to conform in all respects
with, and is subject to, all applicable provisions of the Plan.&#160; Any inconsistencies between this Award and the
Plan shall be resolved in accordance with the terms of the Plan.&#160; By acceptance of this Award, the Participant
agrees to be bound by all of the terms of this Award and the Plan.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">10.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Interpretations.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Any dispute, disagreement or question which arises
under, or as a result of, or in any way relates to the interpretation,
construction or application of the Plan and this Award will be determined and
resolved by the Committee.&#160; Such
determination or resolution by the Committee will be final, binding and
conclusive for all purposes.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">11.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Employment
Rights.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Nothing in the Plan or this Award confers on any
Participant any right to continue in the employ of the Company or in any way
affects the Company&#146;s right to terminate the Participant&#146;s employment without
prior notice at any time or for any reason.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">12.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Rights
as Stockholder.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The Recipient shall have no rights as a stockholder
of the Company with respect to any RSUs covered by this Agreement until the issuance
of the shares of Common Stock.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">13.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Section&nbsp;409A
of the Internal Revenue Code.</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The RSUs granted hereunder are intended to avoid the
potential adverse tax consequences to the Participant of Section&nbsp;409A of
the Code, and the Board may make such modifications to this Agreement as it
deems necessary or advisable to avoid such adverse tax consequences.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">14.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Entire
Agreement</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">This Award constitutes the entire agreement between
the parties relative to the subject matter hereof, and supersedes all
proposals, written or oral, and all other communications between the parties
relating to the subject matter of this Award.</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3</font></p>

<div style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">

<hr size="2" width="100%" noshade color="gray" align="left">

</font></div>

</div>
<!-- SEQ.=1,FOLIO='3',FILE='C:\JMS\ayusoof\05-21654-2\task704374\21654-2-ko.htm',USER='myusoof',CD='Dec 14 01:30 2005' -->


<br clear="all" style="page-break-before:always;">


<div style="font-family:Times New Roman;">

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt .5in;text-indent:-.5in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">15.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><u>Amendment</u></b></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">This Award may be modified, amended or rescinded only by a written
agreement executed by both parties signatories to this Award.&#160;&#160; In the event of a conflict between the terms
of this Award and the Plan, the terms of the Plan shall control.</font></p>

<p style="margin:0in 0in .0001pt .5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="font-size:10.0pt;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&#160;IN WITNESS
WHEREOF, </font>the Company has
executed this Agreement in duplicate as of the day and year first above
written.</p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="53%" colspan="3" valign="top" style="padding:0in 0in 0in 0in;width:53.7%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">TETRA TECH, INC.</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="53%" colspan="3" valign="top" style="padding:0in 0in 0in 0in;width:53.7%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="53%" colspan="3" valign="top" style="padding:0in 0in 0in 0in;width:53.7%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.7%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">By:</font></p>
  </td>
  <td width="29%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:29.62%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="20%" valign="top" style="padding:0in 0in 0in 0in;width:20.38%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
 </tr>
</table>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Please indicate your acceptance of the terms and
conditions of this Agreement by signing in the space provided below and
returning a signed copy of this Agreement to the Company. IF A FULLY EXECUTED
COPY OF THIS AGREEMENT HAS NOT BEEN RECEIVED BY THE STOCK PLAN ADMINISTRATOR OF
THE COMPANY, THE COMPANY SHALL REVOKE ALL SHARES ISSUED TO YOU, AND AVOID ALL
OBLIGATIONS, UNDER THIS AGREEMENT.</font></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The
undersigned hereby accepts, and agrees to, all terms and provisions of this
Agreement.</font></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="33%" colspan="3" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:33.34%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="20%" valign="top" style="padding:0in 0in 0in 0in;width:20.36%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="33%" colspan="3" valign="top" style="border:none;padding:0in 0in 0in 0in;width:33.34%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Employee Signature</font></p>
  </td>
  <td width="20%" valign="top" style="padding:0in 0in 0in 0in;width:20.36%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="33%" colspan="3" valign="top" style="padding:0in 0in 0in 0in;width:33.34%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="20%" valign="top" style="padding:0in 0in 0in 0in;width:20.36%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="12%" colspan="2" valign="top" style="padding:0in 0in 0in 0in;width:12.04%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Printed Name:</font></p>
  </td>
  <td width="21%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:21.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="20%" valign="top" style="padding:0in 0in 0in 0in;width:20.36%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="12%" colspan="2" valign="top" style="padding:0in 0in 0in 0in;width:12.04%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="21%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:21.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
  <td width="20%" valign="top" style="padding:0in 0in 0in 0in;width:20.36%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr>
  <td width="46%" valign="top" style="padding:0in 0in 0in 0in;width:46.3%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="4%" valign="top" style="padding:0in 0in 0in 0in;width:4.62%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Date:</font></p>
  </td>
  <td width="28%" colspan="2" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:28.72%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
  <td width="20%" valign="top" style="padding:0in 0in 0in 0in;width:20.36%;">
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
  </td>
 </tr>
 <tr height="0">
  <td width="346" style="border:none;"></td>
  <td width="35" style="border:none;"></td>
  <td width="56" style="border:none;"></td>
  <td width="159" style="border:none;"></td>
  <td width="152" style="border:none;"></td>
 </tr>
</table>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>

<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4</font></p>

<div style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">

<hr size="2" width="100%" noshade color="gray" align="left">

</font></div>

</div>
<!-- SEQ.=1,FOLIO='4',FILE='C:\JMS\ayusoof\05-21654-2\task704374\21654-2-ko.htm',USER='myusoof',CD='Dec 14 01:30 2005' -->


</body>

</html>
</TEXT>
</DOCUMENT>
