Glossary

A USDOT number is the ID the Federal Motor Carrier Safety Administration (FMCSA) gives a company that runs commercial vehicles. A company hauling cargo between states must have one, and some states require one for trucks that stay inside the state. FMCSA uses it to keep the company's safety record from audits, inspections and crash reports.¹ Listings built from the registry show the number and link to its record.

An MC number is a company's interstate operating authority, which FMCSA also calls a docket number. Companies that need operating authority apply for it on top of their USDOT number.² Authority can also show as an FF or MX number, and a private carrier, one hauling only its own cargo, doesn't need it.³

In FMCSA's rules, interstate commerce is transportation between a place in one state and a place outside it. Intrastate commerce is everything else.⁴ An intrastate carrier works entirely within one state, on trips that don't start or end in another state or country.² A company's SAFER record shows which it registered as, under Carrier Operation.⁵

Power units are the vehicles a carrier owns, trip-leases or term-leases, as FMCSA counts them.² A contractor reports the number on its registration, and the fleet size on this site's listings comes from it.

Cut and fill is using the material dug from high spots, the cut, to fill nearby low areas.⁶ When the cuts don't supply enough, the rest of the fill is brought in from outside the site.⁷

Grading is reshaping the ground to the elevations on a site plan. It gives a site the shape buildings need and helps control stormwater and erosion during and after construction, and low spots may need fill brought in.⁸

Compaction is pressing loosely placed fill into a denser layer, with heavy equipment built for it. Fill goes down in layers called lifts, and each is compacted to a required density.⁹ Dug soil takes up more room in a truck than it did in the ground, and usually less once it's compacted into fill.⁷

Spoils are the soil and other material dug out of an excavation. OSHA requires them to be kept at least 2 feet from the edge of a trench.^{10, 11}

Mobilization is moving a contractor's crew, equipment and supplies to the job site. On public works contracts it's paid as its own lump sum.^{12, 13} The cost estimator adds a published mobilization range for a rural job with no access yet.

A one-call center takes your request to dig and passes it to the companies that run buried lines where you'll be digging. They mark their lines with flags or paint, and the call is free. Every state has one,¹⁴ and 811 is the free national number that reaches it.¹⁵ How much notice you have to give is set by each state, and every state's rules page has it.