Sukut Construction might be the biggest dirt moving contractor in the nation. Right now most of their scrapers are parked due to the collapse of the housing market. But they're big and know how to move dirt.
www.sukut.com
Pinnick Inc, formerly Signs & Pinnick runs a big fleet of 657E's. Solely a dirt moving contractor, they move dirt
fast which earned them the title "Screams & Panic" from a bunch of the Local #12 scraper hands.
www.pinnickinc.com
Teichert Construction does a lot of mass grading work in California. Last time I was out there they were working on a large residential development with Granite Construction.
www.http://www.teichert.com/teichert-construction.cfm
Ralph D. Mitzel has a pretty decent fleet of scrapers. All of which are old, but kept in cherry condition. He recently laid off one of his 651B hands after 10 years, who ended up spending the summer working for me running a 16. Last I heard he had most of his iron parked due to current market conditions.
Granite Construction is a pretty big player in mass grading in California as well. They're spread out so much nationwide that their fleet fluctuates quite regularly, but I've seen several of their projects in California with decent sized spreads of 637G's and 657E's.
I know Kiewit Pacific Co. has 22 657E's on the Schaeffer Ranch project in central California currently. There used to be video on YouTube of those scrapers on that project.
Skanska USA Civil has done some big Federal Highway projects in California involving some decent scraper fleets. I don't know what their current status is, but I know from watching the Central Federal Lands Highway Division's website they're a pretty active player in federal transportation projects on the west coast.
www.usacivil.skanska.com