Top 100 Contractors in PSC B510: Environmental Studies and Assessments, Aug 2025–Jul 2026

Parent companies by net contract obligations Aug 1, 2025 – Jul 31, 2026 Code page on GovTribe

The latest 12 months. See the newest fiscal year's list: Top Contractors in PSC B510: Environmental Studies and Assessments, FY2025.

The top 10 won 56% of PSC B510 contract dollars from August 2025 through July 2026

Ranking facts

Contract obligations
$250,726,496 Net of deobligations, by contracts coded PSC B510
Contractors
204 Parent companies with an obligation
Largest contractor
Amentum Holdings, Inc. $38.9 million, 14.4% of obligations
Data as of

Contract actions from FPDS (SAM.gov). How the rankings work · Download all 100 rows as CSV · Free to reuse with credit to GovTribe (CC BY 4.0)

Full ranking

Rank Contractor Net obligations Share Trend
1 $38,867,641
Rank history: not on the FY2021–FY2023 lists, #36 in FY2024 and #1 in FY2025; unchanged since Aug 2024–Jul 2025.
2 $28,352,696
Rank history: #95 in FY2021, not on the FY2022–FY2024 lists and #5 in FY2025; new, not ranked in Aug 2024–Jul 2025.
3 $26,485,754
Rank history: not on the FY2021–FY2022 lists, #41 in FY2023, not on the FY2024 list and #3 in FY2025; up 49 since Aug 2024–Jul 2025.
4 $12,050,946
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
5 $8,887,899
Rank history: not on the FY2021–FY2024 lists and #29 in FY2025; new, not ranked in Aug 2024–Jul 2025.
6 $8,731,862
Rank history: not on the FY2021–FY2022 lists, #22 in FY2023, #42 in FY2024 and #7 in FY2025; up 30 since Aug 2024–Jul 2025.
7 $8,393,259
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
8 $6,934,351
Rank history: #2 in FY2021, #12 in FY2022, #13 in FY2023, #7 in FY2024 and #6 in FY2025; down 2 since Aug 2024–Jul 2025.
9 $6,635,104
Rank history: not on the FY2021–FY2024 lists and #23 in FY2025; up 24 since Aug 2024–Jul 2025.
10 $5,892,853
Rank history: #83 in FY2021, #47 in FY2022, #31 in FY2023, #4 in FY2024 and #4 in FY2025; down 7 since Aug 2024–Jul 2025.
11
Jacobs Engineering Group Inc.
$5,465,312
Rank history: not on the FY2021–FY2023 lists, #10 in FY2024 and #8 in FY2025; down 1 since Aug 2024–Jul 2025.
12 $5,291,875
Rank history: not on the FY2021–FY2023 lists, #23 in FY2024 and #9 in FY2025; down 1 since Aug 2024–Jul 2025.
13 $5,108,588
Rank history: not on the FY2021 list, #39 in FY2022, #28 in FY2023, not on the FY2024 list and #32 in FY2025; up 18 since Aug 2024–Jul 2025.
14 $5,051,141
Rank history: #7 in FY2021, #2 in FY2022, #1 in FY2023, #3 in FY2024 and #2 in FY2025; down 12 since Aug 2024–Jul 2025.
15 $4,980,197
Rank history: #61 in FY2021, #52 in FY2022, #18 in FY2023, #28 in FY2024 and #14 in FY2025; up 3 since Aug 2024–Jul 2025.
16 $4,750,146
Rank history: not on the FY2021–FY2022 lists, #25 in FY2023, #18 in FY2024 and #13 in FY2025; down 11 since Aug 2024–Jul 2025.
17 $4,635,519
Rank history: not on the FY2021–FY2024 lists and #12 in FY2025; new, not ranked in Aug 2024–Jul 2025.
18
Rmec Environmental Inc
$3,419,660
Rank history: not on the FY2021–FY2022 lists, #20 in FY2023, #17 in FY2024 and #16 in FY2025; down 2 since Aug 2024–Jul 2025.
19 $3,295,805
Rank history: #22 in FY2021, #5 in FY2022, #3 in FY2023, #12 in FY2024 and #21 in FY2025; down 12 since Aug 2024–Jul 2025.
20 $2,881,471
Rank history: not on the FY2021 list, #6 in FY2022, #7 in FY2023, #40 in FY2024 and not on the FY2025 list; up 41 since Aug 2024–Jul 2025.
21 $2,791,569
Rank history: not on the FY2021–FY2022 lists, #27 in FY2023, not on the FY2024 list and #19 in FY2025; up 190 since Aug 2024–Jul 2025.
22 $2,467,103
Rank history: #58 in FY2021, #69 in FY2022, #67 in FY2023, #13 in FY2024 and #53 in FY2025; up 63 since Aug 2024–Jul 2025.
23
Kemron Environmental Services Inc.
$2,435,278
Rank history: not on the FY2021–FY2023 lists, #2 in FY2024 and not on the FY2025 list; up 77 since Aug 2024–Jul 2025.
24 $2,432,433
Rank history: not on the FY2021 list, #30 in FY2022, not on the FY2023 list, #80 in FY2024 and not on the FY2025 list; up 48 since Aug 2024–Jul 2025.
25 $1,858,945
Rank history: #28 in FY2021, #15 in FY2022, #29 in FY2023, #9 in FY2024 and not on the FY2025 list; down 5 since Aug 2024–Jul 2025.
26 $1,792,560
Rank history: #9 in FY2021, #14 in FY2022, #15 in FY2023, #15 in FY2024 and #10 in FY2025; down 14 since Aug 2024–Jul 2025.
27 $1,759,547
Rank history: not on the FY2021 list, #27 in FY2022, #30 in FY2023, #30 in FY2024 and #22 in FY2025; down 1 since Aug 2024–Jul 2025.
28 $1,735,877
Rank history: not on the FY2021–FY2022 lists, #12 in FY2023, #31 in FY2024 and #20 in FY2025; down 6 since Aug 2024–Jul 2025.
29 $1,634,791
Rank history: not on the FY2021–FY2022 lists, #35 in FY2023, #37 in FY2024 and #25 in FY2025; unchanged since Aug 2024–Jul 2025.
30
R Ward & Associates Inc.
$1,446,581
Rank history: not on the FY2021–FY2024 lists and #31 in FY2025; new, not ranked in Aug 2024–Jul 2025.
31 $1,267,912
Rank history: #36 in FY2021, #36 in FY2022, #46 in FY2023, #62 in FY2024 and #26 in FY2025; up 4 since Aug 2024–Jul 2025.
32 $1,262,815
Rank history: not on the FY2021–FY2023 lists, #76 in FY2024 and #48 in FY2025; up 10 since Aug 2024–Jul 2025.
33 $1,247,287
Rank history: not on the FY2021–FY2024 lists and #30 in FY2025; up 92 since Aug 2024–Jul 2025.
34 $1,118,722
Rank history: #12 in FY2021, #41 in FY2022, #40 in FY2023, #32 in FY2024 and #38 in FY2025; up 32 since Aug 2024–Jul 2025.
35 $1,111,753
Rank history: #54 in FY2021, not on the FY2022–FY2023 lists, #35 in FY2024 and #36 in FY2025; down 5 since Aug 2024–Jul 2025.
36
Southeastern Archaeological Research LLC
$1,091,020
Rank history: #23 in FY2021, #35 in FY2022, #48 in FY2023, #54 in FY2024 and #15 in FY2025; down 21 since Aug 2024–Jul 2025.
37 $1,080,247
Rank history: not on the FY2021–FY2024 lists and #39 in FY2025; new, not ranked in Aug 2024–Jul 2025.
38 $1,054,384
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
39 $990,371
Rank history: #67 in FY2021, #73 in FY2022, #65 in FY2023, #53 in FY2024 and #41 in FY2025; down 5 since Aug 2024–Jul 2025.
40 $948,594
Rank history: #24 in FY2021, #72 in FY2022, #16 in FY2023, #38 in FY2024 and #40 in FY2025; down 1 since Aug 2024–Jul 2025.
41
EA Engineering Science and Technology Inc. PBC
$947,269
Rank history: not on the FY2021–FY2023 lists, #34 in FY2024 and #35 in FY2025; down 16 since Aug 2024–Jul 2025.
42
Swca Incorporated
$923,834
Rank history: not on the FY2021–FY2023 lists, #29 in FY2024 and #56 in FY2025; down 5 since Aug 2024–Jul 2025.
43 $897,925
Rank history: #20 in FY2021, #57 in FY2022, #49 in FY2023, #69 in FY2024 and #28 in FY2025; down 2 since Aug 2024–Jul 2025.
44 $896,128
Rank history: not on the FY2021–FY2023 lists, #75 in FY2024 and #44 in FY2025; up 26 since Aug 2024–Jul 2025.
45 $878,651
Rank history: #88 in FY2021, #58 in FY2022, #47 in FY2023, #77 in FY2024 and #49 in FY2025; up 19 since Aug 2024–Jul 2025.
46 $864,775
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
47 $831,549
Rank history: not on the FY2021–FY2023 lists, #45 in FY2024 and not on the FY2025 list; up 101 since Aug 2024–Jul 2025.
48 $791,926
Rank history: #91 in FY2021, #23 in FY2022, #24 in FY2023, #43 in FY2024 and not on the FY2025 list; up 27 since Aug 2024–Jul 2025.
49 $762,900
Rank history: not on the FY2021–FY2025 lists; up 124 since Aug 2024–Jul 2025.
50 $732,900
Rank history: not on the FY2021–FY2024 lists and #45 in FY2025; down 3 since Aug 2024–Jul 2025.
51 $644,835
Rank history: not on the FY2021–FY2024 lists and #33 in FY2025; down 19 since Aug 2024–Jul 2025.
52 $631,886
Rank history: #99 in FY2021, not on the FY2022–FY2023 lists, #94 in FY2024 and #37 in FY2025; down 2 since Aug 2024–Jul 2025.
53 $626,577
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
54 $580,435
Rank history: not on the FY2021–FY2024 lists and #79 in FY2025; up 68 since Aug 2024–Jul 2025.
55 $545,000
Rank history: not on the FY2021 list, #63 in FY2022, not on the FY2023 list, #74 in FY2024 and not on the FY2025 list; up 117 since Aug 2024–Jul 2025.
56 $503,285
Rank history: not on the FY2021–FY2023 lists, #1 in FY2024 and #73 in FY2025; up 30 since Aug 2024–Jul 2025.
57 $500,000
Rank history: not on the FY2021–FY2022 lists, #94 in FY2023, not on the FY2024 list and #55 in FY2025; new, not ranked in Aug 2024–Jul 2025.
58 $467,093
Rank history: not on the FY2021–FY2024 lists and #60 in FY2025; up 128 since Aug 2024–Jul 2025.
59 $456,449
Rank history: not on the FY2021–FY2023 lists, #59 in FY2024 and #50 in FY2025; down 10 since Aug 2024–Jul 2025.
60 $439,814
Rank history: not on the FY2021–FY2024 lists and #59 in FY2025; up 68 since Aug 2024–Jul 2025.
61 $415,148
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
62 $400,000
Rank history: not on the FY2021–FY2023 lists, #89 in FY2024 and #47 in FY2025; down 14 since Aug 2024–Jul 2025.
63 $380,111
Rank history: not on the FY2021 list, #60 in FY2022, #39 in FY2023, #46 in FY2024 and #63 in FY2025; new, not ranked in Aug 2024–Jul 2025.
64 $370,337
Rank history: not on the FY2021–FY2024 lists and #46 in FY2025; down 5 since Aug 2024–Jul 2025.
65 $369,145
Rank history: not on the FY2021–FY2024 lists and #54 in FY2025; up 6 since Aug 2024–Jul 2025.
66 $368,700
Rank history: not on the FY2021 list, #66 in FY2022, #63 in FY2023, #97 in FY2024 and not on the FY2025 list; up 81 since Aug 2024–Jul 2025.
67 $351,597
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
68 $350,280
Rank history: #59 in FY2021, #88 in FY2022, #100 in FY2023, #71 in FY2024 and #57 in FY2025; down 24 since Aug 2024–Jul 2025.
69
Seva EHS Inc
$317,610
Rank history: not on the FY2021–FY2025 lists; up 11 since Aug 2024–Jul 2025.
70 $316,520
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
71 $314,904
Rank history: not on the FY2021–FY2024 lists and #64 in FY2025; new, not ranked in Aug 2024–Jul 2025.
72 $300,548
Rank history: #39 in FY2021, #33 in FY2022, not on the FY2023 list, #55 in FY2024 and #58 in FY2025; down 3 since Aug 2024–Jul 2025.
73 $300,080
Rank history: not on the FY2021 list, #10 in FY2022, #17 in FY2023, #22 in FY2024 and #11 in FY2025; down 60 since Aug 2024–Jul 2025.
74 $295,734
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
75 $295,592
Rank history: not on the FY2021–FY2024 lists and #67 in FY2025; new, not ranked in Aug 2024–Jul 2025.
76 $294,106
Rank history: #66 in FY2021, not on the FY2022–FY2024 lists and #68 in FY2025; up 6 since Aug 2024–Jul 2025.
77 $283,836
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
78 $270,336
Rank history: not on the FY2021–FY2024 lists and #71 in FY2025; new, not ranked in Aug 2024–Jul 2025.
79 $267,601
Rank history: not on the FY2021–FY2024 lists and #69 in FY2025; up 4 since Aug 2024–Jul 2025.
80
SES Inc.
$266,300
Rank history: not on the FY2021–FY2024 lists and #75 in FY2025; up 8 since Aug 2024–Jul 2025.
81 $259,000
Rank history: not on the FY2021–FY2024 lists and #74 in FY2025; up 125 since Aug 2024–Jul 2025.
82 $257,606
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
83 $254,217
Rank history: not on the FY2021–FY2024 lists and #61 in FY2025; new, not ranked in Aug 2024–Jul 2025.
84
Avanti Corporation
$251,667
Rank history: not on the FY2021–FY2022 lists, #90 in FY2023 and not on the FY2024–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
85 $248,711
Rank history: not on the FY2021–FY2024 lists and #76 in FY2025; new, not ranked in Aug 2024–Jul 2025.
86 $244,745
Rank history: not on the FY2021–FY2024 lists and #77 in FY2025; up 13 since Aug 2024–Jul 2025.
87 $243,882
Rank history: not on the FY2021–FY2024 lists and #87 in FY2025; up 29 since Aug 2024–Jul 2025.
88
Deloitte 2 awardees, including Deloitte & Touche LLP
$238,217
Rank history: not on the FY2021–FY2025 lists; new, not ranked in Aug 2024–Jul 2025.
89 $220,617
Rank history: #45 in FY2021, #38 in FY2022, #44 in FY2023, #24 in FY2024 and #80 in FY2025; down 62 since Aug 2024–Jul 2025.
90 $215,245
Rank history: not on the FY2021–FY2024 lists and #82 in FY2025; new, not ranked in Aug 2024–Jul 2025.
91 $213,154
Rank history: not on the FY2021–FY2024 lists and #83 in FY2025; new, not ranked in Aug 2024–Jul 2025.
92 $209,252
Rank history: not on the FY2021–FY2022 lists, #61 in FY2023, not on the FY2024 list and #84 in FY2025; up 78 since Aug 2024–Jul 2025.
93 $195,000
Rank history: not on the FY2021–FY2024 lists and #86 in FY2025; new, not ranked in Aug 2024–Jul 2025.
94
One Network Enterprises Inc. Through TRC Environmental Corporation
$189,950
Rank history: not on the FY2021–FY2024 lists and #89 in FY2025; up 9 since Aug 2024–Jul 2025.
95 $188,680
Rank history: not on the FY2021–FY2025 lists; down 4 since Aug 2024–Jul 2025.
96 $186,905
Rank history: not on the FY2021–FY2024 lists and #91 in FY2025; new, not ranked in Aug 2024–Jul 2025.
97
Relife Recycling S.R.L.
$185,854
Rank history: not on the FY2021–FY2025 lists; up 11 since Aug 2024–Jul 2025.
98 $182,062
Rank history: #18 in FY2021, #28 in FY2022, #32 in FY2023, #33 in FY2024 and #18 in FY2025; down 81 since Aug 2024–Jul 2025.
99 $178,050
Rank history: not on the FY2021–FY2024 lists and #92 in FY2025; new, not ranked in Aug 2024–Jul 2025.
100 $177,039
Rank history: not on the FY2021–FY2022 lists, #66 in FY2023, #78 in FY2024 and #85 in FY2025; up 54 since Aug 2024–Jul 2025.
Show 75 more

100 of 204 contractors listed here. See the rest on GovTribe.

How this ranking works

  • Source: every contract action FPDS records (as published on SAM.gov) in the period, as GovTribe received it.
  • Amounts are net obligations: what was obligated, less what was deobligated. Shares are of $269 million obligated before deobligations, so they never pass 100%.
  • Parent companies: each action counts under the ultimate parent its award record names, or under the awardee when it names none, so no dollar counts twice. An awardee whose own actions mostly name no parent, and that no other company's actions name as their parent, rolls up its SAM.gov registration's chain of parent companies: it counts under the first company there that other companies' actions name as their parent, or under the parent most of a company's own actions name, whichever comes first; with neither, under the highest company in the chain with federal contracts of its own. Joint ventures stay companies of their own. Parents of the same name (Inc., LLC and the like aside) count as one company, since FPDS records a company's parent under more than one UEI over time. GovTribe corrects a few parents and names by hand; see the corrections.
  • Period: the trailing 12 months end with the last month that ended at least 90 days ago, because the Department of Defense reports its contract actions to FPDS about 90 days late. The list is rebuilt each night.
  • Rank changes compare with Aug 2024–Jul 2025. "New" marks a company outside that period's top 500, and "Returned" one of those that was on an earlier fiscal year's list.
  • Rank lines show each company's rank on every fiscal year's list since FY2021, #1 at the top, on a scale that gives the top of the list more room. A dashed stretch spans years it wasn't on the list.
  • Placeholder recipients FPDS uses when it names no company ("Miscellaneous Foreign Contractors" and the like) aren't ranked.

Quick answers

Who were the top 10 PSC B510 contractors in Aug 2025–Jul 2026?

1. Amentum Holdings, Inc. ($38.9M), 2. Vernadero Group Inc. ($28.4M), 3. Gulf South Research Corp ($26.5M), 4. Environmental Restoration LLC ($12.1M), 5. Tierra Right of Way Services Ltd ($8.89M), 6. Dawson Solutions LLC ($8.73M), 7. ECO & Associates, Inc. ($8.39M), 8. Eastern Research Group Inc. ($6.93M), 9. Kfs, LLC ($6.64M), 10. Hdr, Inc. ($5.89M).

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