Perhaps a part of this group of companies....
http://www.ellisenv.com/main.htm
As with all these kinds of outfits....read the contract very carefully! If you get stiffed for pay...who actually holds the contract with the US government and how many subcontractors are between you and the prime contractor? That has an almighty affect upon your ability to go against them for breach of contract.
It could be on the up and up...but be careful folks!