TETRA TECH, INC.

R7 START VI: REMOVAL SITE EVALUATION AT 10TH STREET SITE IN COLUMBUS, NEBRASKA

R7 START VI: SUPPORT & MANAGEMENT KANSAS CITY WAREHOUSE MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO PROVIDE ADDITIONAL INCREMENTAL FUNDING.

R7 START VI: NEWTON COUNTY MINE TAILINGS TECHNICAL SUPPORT

R7 START VI: RESIDENTIAL SAMPLING, ANALYSIS, AND DATABASE UPDATE FOR SOUTHWEST JEFFERSON COUNTY MINING MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO INCREASE THE CEILING AND ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE

R7 START VI: RA TECHNICAL SUPPORT, WASHINGTON COUNTY LEAD DISTRICTS - FURNACE CREEK & OLD MINES (OPTION) POTOSI MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO INCREASE THE CEILING, ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES, AND EXTEND T

R7 START VI: TECHNICAL ASSISTANCE SUPPORT TO EPA TO SUPPORT EMERGENCY RESPONSES MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER.

R7 START VI: SUPPORT & MANAGEMENT NEBRASKA SUBAREA SUPPORT MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER.

R7 START VI: HRS SUPPORT GENERAL MOTORS SIOUX CITY MOD P00002: THE PURPOSE OF THIS MODIFICATION IS TO UPDATE THE PERIOD OF PERFORMANCE END DATE AND PROVIDE ADDITIONAL FUNDING.

R7 START VI: ORONOGO-DUENWEG MINING BELT TCRA

R7 START VI: SAMPLING AND ANALYSIS SUPPORT CHEROKEE COUNTY

R7 START VI: TECHNICAL SUPPORT TO THE OMAHA-COUNCIL BLUFFS SUBAREA SUPPORT MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER.

R7 START VI: QUAD CITIES SUB-AREA TECHNICAL SUPPORT MOD P00002: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER.

R7 START VI: TECHNICAL SUPPORT TO THE SIOUXLAND SUB-AREA MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER.

R7 START VI: CENTRAL KANSAS WETLANDS SUBAREA SUPPORT MOD P00002: THE PURPOSE OF THIS MODIFICATION IS TO PROVIDE ADDITIONAL INCREMENTAL FUNDING FOR CONTINUED SUPPORT.

R7 START VI: SUPERFUND TECHNICAL ASSESSMENT & RESPONSE TEAM 6 MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO INCORPORATE CLAUSE 52.222-90 ADDRESSING DEI DISCRIMINATION BY FEDERAL CONTRACTORS (APR 2026)

R7 START VI: TECHNICAL AND ANALYTICAL SERVICES FOR FIELD SUBCONTRACT LABORATORY ASSISTANCE MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO INCREASE THE TASK ORDER CEILING, ADD INCREMENTAL FUNDING AND EXTEND THE PERIOD OF PERFORMANCE.

R7 START VI: OIL/OPA EMERGENCY RESPONSE TECHNICAL ASSISTANCE AT ONION CREEK

R7 START VI: REMOVAL DATA MANAGEMENT SUPPORT FOR EMERGENCY RESPONSE AND REMOVAL PROGRAM MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO PROVIDE ADDITIONAL INCREMENTAL FUNDING.

R7 START VI: GREAT RIVERS SUBAREA CONTINGENCY PLAN (GRSACP) PROJECT. MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER.

R7 START VI: ST. LOUIS/FENTON WAREHOUSE SUPPORT & EQUIPMENT MAINTENANCE MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER AND EXTEND THE PERI

R7 START VI: WEST BURLINGTON VOC

R7 START VI: SUPPORT & MANAGEMENT GREATER ST. LOUIS SUBAREA SUPPORT MOD P00001: THE PURPOSE OF THIS MODIFICATION IS TO ADD INCREMENTAL FUNDING FOR SEVERABLE SERVICES IN ACCORDANCE WITH THE ORIGINAL SCOPE OF THE TASK ORDER.

R7 START VI: SEMO ALT WATER DATA MANAGEMENT MOD P00001: EXTEND POP FOR CONTINUED WATER DATA MANAGEMENT SUPPORT.

R7 START VI: NCMT RESIDENTIAL TECH SUPPORT REMEDIAL MOD P00001: THE PURPOSE OF THIS ZERO-DOLLAR MODIFICATION IS TO UPDATE THE ENDING PERIOD OF PERFORMANCE DATE.

R7 START VI: ODMB OU3 RESIDENTIAL REMEDIAL MOD P00002: THE PURPOSE OF THIS MODIFICATION IS TO PROVIDE INCREMENTAL FUNDING FOR SEVERABLE SERVICES.