| TLTxm - Leander Ready Mix | Leander | TX | — | ◇ UNVERIFIED |
| TSTxm - San Marcos Ready Mix | San Marcos | TX | — | ◇ UNVERIFIED |
| TTTxm - Taylor Ready Mix | Taylor | TX | — | ◇ UNVERIFIED |
| TTTxm - Tesla Rd Ready Mix | Austin | TX | — | ◇ UNVERIFIED |
| TWTxm - Westside Ready Mix | San Antonio | TX | — | ◇ UNVERIFIED |
| URUmatilla Ready Mix | Pendleton | OR | — | ◇ UNVERIFIED |
| URUmatilla Ready Mix Hermiston Plant | Hermiston | OR | — | ◇ UNVERIFIED |
| UCUnicon Concrete Incorporated | High Point | NC | — | ◇ UNVERIFIED |
| UCUnicon Concrete Incorporated Plant Number 6 | Durham | NC | — | ◇ UNVERIFIED |
| UCUnimin Corporation | Gleason | TN | — | ◇ UNVERIFIED |
| UCUniontown Concrete Plt | Hopwood | PA | — | ◇ UNVERIFIED |
| UCUnited Concrete CORP | Waukegan | IL | — | ◇ UNVERIFIED |
| UCUnited Contractors Midwest | Chapin | IL | — | ◇ UNVERIFIED |
| UMUnited Materials Company-st Louis | Saint Louis | MO | — | ◇ UNVERIFIED |
| UMUnited Metro Materials | Phoenix | AZ | — | ◇ UNVERIFIED |
| UMUnited Metro Materials (dba Rinker Materials) El Mirage 106 | El Mirage | AZ | — | ◇ UNVERIFIED |
| URUnited Ready Mix INC | Pekin | IL | — | ◇ UNVERIFIED |
| URUnited Ready Mix INC | Peoria | IL | — | ◇ UNVERIFIED |
United States Gypsum Company | Spruce Pine | NC | — | ◇ UNVERIFIED |
Universal Minerals International INC. | Louisville | KY | — | ◇ UNVERIFIED |
| URUpchurch Ready Mix Concrete CO | East Saint Louis | IL | — | ◇ UNVERIFIED |
| URUpchurch Ready Mix Concrete CO INC | Belleville | IL | — | ◇ UNVERIFIED |
| UCUpper Cape Ready Mix | East Falmouth | MA | — | ◇ UNVERIFIED |
| UUrbix | Mesa | AZ | — | ◇ UNVERIFIED |
| UIU-rent INC. | Camarillo | CA | — | ◇ UNVERIFIED |
| UIU-rent INC. | Saticoy | CA | — | ◇ UNVERIFIED |
| UNUs301 Nice-middleton Bridge Replacement Project | Newburg | MD | — | ◇ UNVERIFIED |
| UEUs69 Express 135th Loop Ramp | Overland Park | KS | — | ◇ UNVERIFIED |
| UEUs69 Express Bvpw Batch Plant | Overland Park | KS | — | ◇ UNVERIFIED |
| UNUsace New River Chamber Batch Concrete Plt | Monaca | PA | — | ◇ UNVERIFIED |
| UCUSA Concrete LLC | La Grande | OR | — | ◇ UNVERIFIED |
| UFUsc - Ferrara Brothers LLC - Chelsea Road | Staten Island | NY | — | ◇ UNVERIFIED |
| UKUsc - Kings LLC - Inwood | Inwood | NY | — | ◇ UNVERIFIED |
| UKUsc - Kings LLC - on Time | Flushing | NY | — | ◇ UNVERIFIED |
| UCU.s. Concrete Company/superior Concrete Materials | Washington | DC | — | ◇ UNVERIFIED |
| UCU.s. Concrete, INC. | Staten Island | NY | — | ◇ UNVERIFIED |
| UCU.s. Concrete, INC. | Staten Island | NY | — | ◇ UNVERIFIED |
| UCUS Concrete On-site INC | Camp Grove | IL | — | ◇ UNVERIFIED |
| UDU.s. Dol-osha Corpus Christi Area Office | San Juan | TX | — | ◇ UNVERIFIED |
| UOUsdol Osha - Ft. Lauderdale Ao | Miami | FL | — | ◇ UNVERIFIED |
| UDU.s. Dol-osha Houston South Area Office | Galveston | TX | — | ◇ UNVERIFIED |
| UOUsdol Osha - Tampa Ao | Orlando | FL | — | ◇ UNVERIFIED |
| USU.s. Silica Company, | Middleton | TN | — | ◇ UNVERIFIED |
| USUS Silica Kosse Plant | Kosse | TX | — | ◇ UNVERIFIED |
| USUS Steel Corporation | Lorain | OH | — | ◇ UNVERIFIED |
| UCUstone Cement Products & Solution LLC | Medley | FL | — | ◇ UNVERIFIED |
| UTUtica Transit Mix and Supply | Sterling Heights | MI | — | ◇ UNVERIFIED |
| VDValco Div-3 | Lamar | CO | — | ◇ UNVERIFIED |
| VIValco INC | Canon City | CO | — | ◇ UNVERIFIED |
| VIValco INC | Rocky Ford 2.0 Mi. E of | CO | — | ◇ UNVERIFIED |